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Wednesday, October 30, 2019

What I've learned from men by Barbara ehrenreich Essay

What I've learned from men by Barbara ehrenreich - Essay Example I don’t agree when she said that we may be able to learn from men what to do with anger (227), as women have long since learned to express anger in a civilized way, positively producing the desired effect, making men realize that women are able to stand for themselves. That does not lessen them as women. Instead it makes them women with substance. Women can be very aggressive but not rude, acknowledging their talents, abilities, skills and success with humility. Expressing oneself nicely rather than looking and waiting for a fight, makes a person better understood and listened to. Women today acknowledge that having education, firm character, belief in oneself and humility, do not make them less of a woman, but rather leads to essentially being a lady. For me being ladylike empowers a woman in getting what she wants. I believe that how you act and treat others determines how others act and treat you. Ehrenreich, Barbara. â€Å"What I’ve Learned From Men† From Idea to Essay 2009: A Rhetoric, Reader, and Handbook. McCuen-Metherell, J.R. and Winkler, A. Boston, MA: Wadsworth, Cengage Learning, 2009. 224-227. Google Books. Web. 5 March

Monday, October 28, 2019

Child Protective Services Essay Example for Free

Child Protective Services Essay Ice users in the state of Hawaii, estimated to have reached 30,000 in 2003, were spending as much as $1. 8 billion every year to maintain their addiction in what has been referred to by U. S Attorney Ed Kubo as the â€Å"highest usage of ice in the country. † (Sinq, 2003) Ice refers to methamphetamine, a strong, extremely addictive stimulant which could be introduced to the body by smoking, sniffing, oral ingestion, or injection and affects the nervous system. (Drug-Rehabs. org, n. d. ) The substance was believed to have been discovered in Japan sometime in 1919 and was actually used as a nasal decongestant in 1932. It was manufactured legally as non-medical tablets in the United States, taking the form of â€Å"dextroamphetamine (Dexedrine) and methamphetamine (Methedrine). † It rapidly became a favorite among athletes, university students, and even long distance truck drivers – people who need to stay alert for long periods of time. An injectable form was developed during the 1960s but was subjected to severe restriction under the Controlled Substance Act of 1970. (Drug-Rehabs. org. n. d. ) Today, Prosecutor Peter Carlisle of Honolulu said that adult people in Hawaii have been turning to ice instead of alcohol – in fact the highest number of adult ice-users (by state) in the entire country is found in the state of Hawaii. In Honolulu, it was estimated that about 38% of all those arrested for various offenses have been found positive for methamphetamine. Moreover, while the average rate of sentenced methamphetamine traffickers for the entire country in 2001 was placed at 14%, the rate for Hawaii had been 51%. (A Message from Honolulu Prosecutor Peter Carlisle, 2007) This only means one thing: ice trafficking in Hawaii has grown to be a very flourishing industry, which, to some people, indicates that ice abuse has already reached epidemic proportions in the state. As a matter of fact, recorded deaths attributed to methamphetamine use have also been steadily on the rise since 2000 when 34 persons were believed to have died from using the substance. In 2001, the number rose to 54 then climbed to 62 in 2002 before decreasing slightly to 56 deaths during the year 2003. In 2004, ice-related deaths rose again to 68 and as of the middle of May 2005, there were already 38 ice-related deaths in the state of Hawaii. According to Dr. Kanthi De Alwis, Chief Medical Examiner of Honolulu, majority of deaths from ice were due to the substance’s effect on the human brain and heart. He said that ice weakens and enlarges the heart, and blocks the coronary arteries. In some of the cases, Alwis said, blood enters the brain, killing the ice user almost instantly. (Drug-Rehabs. org, 2005) User death did not prove to be the only adverse effect of the ice epidemic on Hawaiian society. A much more damaging consequence had been its effect on children. In fact it was observed that although abuse of alcohol and illegal drugs also resulted to fractured families, ice addiction had proven to be more powerful and destructive, consuming â€Å"parents’ lives so quickly that experts placed it in a class of its own. † (Dayton, 2003b) As of 2003, almost 85% of the 7,000 children who were under foster care were children of ice users. Most of these children were traumatized. They also showed signs of being â€Å"angry† and were often destructive in their ways, aside from the fact that most of them lagged in their school work. Many of them have expressed their belief that their parents abandoned them either because something was very wrong with them, or their parents simply stopped loving them. If left unattended, experts feared that these children might end up as substance abusers themselves. At the very least, they are expected to suffer from the long-term effects of living with constant violence and chaos in the family. This is what some health professionals are trying to prevent, according to Jack Maynor who works as a child counselor in a spouse-abuse shelter. (Dayton, 2003a) In many cases, children were separated from their parents because of the parents’ addiction to ice. Families where either or both parents are ice addicts are characterized by violence, child abandonment, or both. Peggy Hilton of the East Hawai’i Child Welfare Services said that there are people who become totally addicted to methamphetamine in only a matter of a couple of weeks. She explained that ice is characterized by â€Å"extreme levels of domestic violence [and that] after a binge, ice users ‘crash’ and can sleep for days, leaving the children in the house to fend for themselves. † According to officials of the Child Protective Services, they are separating up to forty children from their parents every month due to ice addiction in the Big Island alone. (Dayton, 2003b) The effect of parents’ addiction to ice among Hawaiian children has been very extensive. Professionals working with children of methamphetamine abusers often talk about the depressing experiences of these children. James Jolliff, a clinical psychologist from Waimea, recalled working with a girl who found her ice addict father hanging from a tree in their backyard in an attempt to kill himself. He said that while her father was rescued from that suicide attempt, the girl was traumatized and would remain to be so for a long time to come. (Dayton, 2003a)

Saturday, October 26, 2019

Benedict Arnolds Treason Essay -- essays research papers

After defeating British troops in Saratoga, Congress made Benedict Arnold a major general in the Continental Army. Washington wrote a commendation saying that Arnold was a brave officer. Despite the promotion, Arnold remained at the bottom of the list. There were four other major generals superior to him. Arnold was soon off once again to help the northern army. Ticonderoga had fallen back into enemy hands. British General John Burgoyne and his troops were moving rapidly down from Canada toward Albany. Arnold fell under the leadership of General Horatio Gates. Arnold and Gates were complete opposites. Gates appeared cautious and calculating while Benedict was persistent and hasty. Gates held position on an area overlooking the Hudson River. His plan was to wait for an attack. He knew that the British were low on supplies from their long march from Canada and planned on using that to his advantage. Arnold disagreed, urging Gates to attack General Burgoyne during his progress. However, Gates didn’t trust Benedict or believe in his tactics. Once the battle begun there was no holding back. Disobeying Gates orders, Arnold led a furious attack. Upon the barrage of bullets swarming the battlefield, Arnold was shot in the leg. Ironically this was the same leg that had been wounded in t he battle at Montreal. Thanks to Arnold’s valiant effort General Burgoyne and his men were faced with retreating. Over six hundred British soldiers were killed. On October 16, General Burgoyne surrendered his sword to General Gates, instead of Arnold. This had disgruntled Arnold greatly, given that it was his brilliant, tactical assessment that forced the British army to surrender. This had made the victory bittersweet threw his perspective. Following the battle, Arnold lay in an Albany hospital for three months. Arnold left the hospital with a â€Å"fracture box† around his bad leg. Gates distort over Arnold’s disobedience stripped him of his rank. However, the Continental Congress restored his rank as a reward for Arnold’s spirited efforts. After Ticonderoga, Arnold was having problems getting reimbursements from Congress for his expenses. Unfortunately, Arnold lacked receipts for those purchases. Arnold felt his loyalty and honor were in question given that Congress was slow to react to Arnold’s claim. Soon after Washington requested that Arnold come to Valley Forge to converse his ... ...d to the point. He remitted Arnold a draft of 6,000 pounds. Generous as the British were to Arnold, they never completely trusted him as an officer in their service. Though he conducted a raid into Virginia and led the tragic expedition to New London, the British declined to give him a high command. After Cornwallis’ surrender at Yorktown, Arnold took his family to London, where he received both respect and admiration, but no employment. Later, he moved to Canada- to St. John, New Brunswick and entered the shipping business. Eventually, Arnold moved his family back to London and tried to secure command when the war with revolutionary France broke out. Denied an opportunity to return to military, he traded with the West Indies, where he was greatly appreciated. Rejected once more in an effort to help the military, Arnold died in 1801, forlorn and almost forgotten in Britain. His wife out lived him by three years, but had the satisfaction of seeing her children have respectable careers and attain mild fame. If none has achieved such military importance as their ancestor, the tireless â€Å"Dark Eagle† as the Indians called him, none has put self-interest or injured pride before honor.

Thursday, October 24, 2019

An Economically Important Crop

A. sativa is an economically important crop and ranks sixth in world cereal production after wheat, rice, maize barley and sorghum (FAO, 2012). It is an important role as food for human and feed for animals in central high lands of Ethiopia; it is one of the best dual-purpose cereal crops. Ethiopia as a region with wide altitudinal range, substantial temperature, and rainfall differences with diverse edaphic conditions create a wide range of agro-ecological conditions and microenvironments. Ethiopia, is considered as a secondary center of diversity for the oat, little has so far been done towards determining the genetic diversity, population structure and acid soil tolerance capacity screening of Ethiopian oat accessions. More nutritious and high yielding oat varieties are needed to run an efficient livestock industry as well as to secure human food security on which dependence of increasing population is taking ride. So, it becomes important to take advantage of the germplasm available to develop the superior cultivars for specific needs.Thus, the present study was undertaken to identify or catalogue oats genotypes along with the assessment of genetic diversity prevalent in different geographical regions in the country and from USA, Netherlands and Australia. The 176 oat accessions were used for the present investigation and they were sown in a RCBD design with two replications at each site. Observations were recorded on various morpho-agronomic characters viz; plant height (cm), internode length (cm), number of nodes per main stem of a plant, number of tillers /plant, Flag leaf length (cm), length of panicle (cm), number of spikelets per panicle, days to 50% flowering, days to maturity, biological yield per m2 (g), grain yield per m2 (g), and harvest index (%). This study also provides one of the first reported investigations of association analysis in a diverse population of oat, and thus, it will provide a useful benchmark for comparison with future results and with results from other species. Accurate assessment of the levels and patterns of genetic diversity has tremendous importance in the analysis of genetic variability in cultivars; identifying diverse parental combinations to create segregating progenies with maximum genetic variability for further selection; and introgression of genes from more exotic germplasm to broaden the genetic diversity of oats. The results obtained in our study provide a better understanding of genetic diversity along with its aluminium tolerance from different regions of Ethiopia as well as USA and Netherlands and Australia oat germplasm accessionsBased on molecular and agro morphological data there are no clear differentiation between populations; the population that were analyzed as genus level, A. sativa population and A. abyssinica population. The present study revealed that the oat accessions had significant wide range variability with respect to qualitative and quantitative traits. Moreover, the variations observed (both qualitatively and quantitatively) were fairly distributed across the regions/populations the accessions were collected from. These indicated potential genetic diversity prevalent in oat accessions, which can be harnessed future breeding and conservation endeavors in Ethiopia. A high genetic diversity exists in Ethiopian accessions as well as in USA and Netherlands- Australia accessions. There is a significantly higher variation within the populations than among the populations. In addition, there is a significantly higher variation within cultivated as well as within wild than among the cultivated and among wild. Furthermore, there is a significantly higher variation within species than among the species.The molecular diversity analysis was carried out using 19 SSR markers in all the 176 germplasm. The SSR markers showed clear differentiation between wild and cultivated, but they failed to differentiate from Ethiopian and USA and Netherlands-Australia cultivated oat accessions. The following molecular data were recorded for allelic parameters like, number of alleles/effective alleles; average heterozygosity; genetic diversity; and Polymorphic Information Content (PIC), demonstrating the availability of adequate genetic diversity in the wild oat accessions that can be exploited in the future. These variations in the allelic parameters were also noticeable across regions/populations sites. Peculiarly, the geographic populations, Shewa and Gondar and Arsi, had the most excessive number of effective alleles in 176 oat accessions the whole, 81 A. sativa accessions, and A. abyssinica accessions; and expected/unbiased expected heterozygosity measures. This indicated that these regions possess higher importance towards through introgression desirable genes into other oat genotypes in Ethiopia. The following molecular data were recorded for allelic parameters like, number of alleles/effective alleles; average heterozygosity; genetic diversity; and Polymorphic Information Content (PIC), demonstrating the availability of adequate genetic diversity in the wild oat accessions that can be exploited in the future. These variations in the allelic parameters were also noticeable across regions/populations sites. Peculiarly, the geographic populations, Shewa and Gondar and Arsi, had the most excessive number of effective alleles in 176 oat accessions the whole, 81 A. sativa accessions, and A. abyssinica accessions. This indicated that these regions possess higher importance towards through introgression desirable genes into other oat genotypes in Ethiopia.Cluster analysis grouped 176 genotypes into five clusters whereby the individuals within any one cluster are more closely related than are individuals in different clusters. Our expectations were, the hexaploid specie might be grouped together and tetraploid species may have clustered together, while hexaploid and tetraploid species should have to be clustered separately since they possessed different genome. unlikely to our expectation the result showed that hexaploid and tetraploid were grouped together. Clustering these groups were similar both in molecular and agro-morphological data. Similar results were found for molecular data. The DARwin 5.0 software was used to generate the dendrogram. All the genotypes were clustered into 3 clusters of different sizes. On the other hand, results of PCA and various recorded values of important agro-morphological descriptors were jointly used to determine the groups identified in the molecular analysis at a STRUCTURE present k=2. As a result, the first group, USA and the Netherlands – Australia belonged to the cultivated oats, A. sativa; whilst the second groups were predominated by accessions from the Ethiopia, both cultivated and wild. Consequently, it was concluded that Cultivated oat groups had higher genetic diversity than their respective Wild oat counterparts in Ethiopian oat germplasm. The current study showed that Root Length (RL) was affected more by Al toxicity. Lower Al toxicity levels less than 50 Â µM had no significant effect on the growth performance in most oat accessions, while the growth of RL showed a decline with increasing Al concentration and toxicity levels. The impact of Al toxicity on oats germplasm became influential upon toxicity level increments. The optimum Al3+ concentration for tolerance level could be 112.5 Â µM oats. Thus, these accessions should not be recommended in area where soil acidity is predominant. However, A. vaviloviana accessions were highly Al tolerant as revealed by root growth performance and can be promoted in area where soil acidity is a challenge. This study is the first of its kind to evaluate the performance of Ethiopian oats to Al-toxicity. The study clearly showed the possibility of developing lines and genotypes that can tolerate acidity in Ethiopian context and support agricultural development in acidic soil area in the country. In conclusion, the present study generated unique outcomes in terms of directing the phenotypic and molecular genetic diversity; population structure of the genepools; and to identity of sub-groups up to the species level. It is considered to put the platform for future breeding and genetic resource conservation programs in Ethiopia.

Wednesday, October 23, 2019

Preliminary Study of an Automotive Assembly Plant

Politecnico Di Torino 1 Facolta' di Ingegneria Automotive Engineering FINAL ASSEMBLY Preliminary study of an automotive assembly plant for high volume production(1300cars/day with 2 type of cars, 4 doors and 2 doors respectivly, and flexible in volume, 3 shifts of workers) Ma Wei supervisor: Prof. COZZARI GIULIANO Index 1. General infomation from the internship 2. 1 high production volume of the assembly plant 2. 2 pace calculation 2. 3 area calculation and process layout 2. 4 flexibility and automization of the system 2. â€Å"make or buy† decision 2. Review of tutorials and further applications of the tutorial 3. 6 General knowledges aquired from the assembly lecture 3. 7 Extension of the tutorial 3. 8. 1 product breakdown structure(PBS) ; bill of material(BOM) 3. 8. 2 work breakdown structure(WBS) 3. Time analysis and relative calculations 3. 1 working time analysis(WCT, takt time) 3. 2 system length and area calculation 3. 3 facility layout 4. Tool and equipment selection 1. General infomation from the internship 1. high production volume of the assembly plant As is define in the internship reoprt, the production volume of the plant that we study is 1300cars/day, with 3 shifts of workers making the planned working time up to 21 hour a day. We developed a rough plan for the entire assembly production process, and then divided our thesis into four parts according to the function of each part. Following the sequence of each part, they are respectively: Stamping process, body in white process, painting process and fianl assembly process.Normally each department is separated with one another, located in different locations inside an assembly plant, and each department has its own building structure, thus we call them stamping shop, body in white shop, painting shop and final assembly shop. Moreover all of these building structures are placed considering the convenience of the entire manufacturing process, to facilitate the flow of materials and parts, to simplify stocks management. For example, stamping shop normally locates near the gate with a stock area to facilitate the incoming of sheet metal.Body in white shop and painting shop lies in between final assembly shop and stamping shop, in order to shorten transfer process. Finally, final assembly shop often locates beside the supplier park, where massive subgroup parts of a car are stocked. 1. 2 pace calculation Since our focus is on the word â€Å"high volume†, we must estimate the overall pace of the plant. The required standard time can be calculated considering: 1. 1300 cars/day. 2. 3 shifts of workers with 7 availiable working hours per shift. 3.Overall equipment efficiency=90% 4. Standard time STn is the time needed to assemble a car, starting from pressing shop up to final test at final assembly shop. AWT(available working time)=3*7*60=1260 min STn=AWT/1300=0. 97min=58sec. It means that each 58 seconds there will be a car coming out from the plant. 1. 3 area calcula tion The area calculation is decided in the internship report, through the benchmarking result of many plants and we chose the average area of the plants that is most close to our requirements.And here is the decision: Stamping| BIW| Painting| Final Assembly| 40800? | 60900? | 48000? | 71400? | Usually the process layout is like this(I will only focus on the final assembly process): But for the final assembly, I find it more advanced for logistic and warehouse management is I choose the final assembly line like this: In my later discussion, we can see more advantages of this kind of solution according to the three main sub-processes of final assembly. 1. 3 flexibility;automization of the systemEquipments are most devoted resource since nowadays factories are normally capital intensive. So we have to determine the automization level at the first approach of an assembly plant. The four processes, stamping, body in white, painting and final assembly, have their own process capability a nd different automization level. Here is the automization level selection criteria and methods to be flexible of the system. And we will make our choice accordingly. Stamping STAMPING| COST AND THE CHOICE| 1. ransfer muiti-station mechanical presses with a very high cadence(over than 15 cycles/min) fitting with very high production rate(over than 600 series/day)| Very high, not fitable for our plant because according our make or buy decision, we only make necessary body parts in order to save capital and better focus on â€Å"core business†. | 2. traditional mechanical or new generations hydraulic presses with a medium cadence(between 10 and 15 cycles/min), interconnected by automatic systems, fitting for medium production rate(60-600 series/day)| This fits our production system adequately.Since our assumed working cycle time is 6sec(=10 cycles/min) and it meets the requirement of 1300cars/day. On the other side, this is capital intensive but not as expensive as the first one . | 3. traditional hydraulic or water forming presses, with manual loading/unloading, with low cadence, fitting for low production rate(less than 60 series/day)| This criterion is not fit for mass production. Nowadays labor intensive production is used for the elite market. | Major factors influcing cost: press and dies depreciation, maintenance costs and material handling.And thus it is very important to maintain a good level of overall equipment efficiency and a good utilization level. Furthermore, in order to keep the production cost low, sheet metal usage degree must be optimized, through detailed study of cutting schemes and stamping methods and technology(sheet metal stamping dimensioning). | Flexibility: the process flexibility is reached to the required level(2 different types of cars with 9 different parts to stamp) through changing of dies according to detailed production plan. We should avoid to change dies too frequently, for the sake of saving more productive up time.Th e production plan should follow the material requirement plan of later processes, and the logistic department should set adequate arrangements for the finished parts. | Body in white For high or medium volumes body in white welding and assembling, hard automation(robot intensive) and flexible production systems are used. Assembling tools are specific for the parts of each type of car. System flexibility/convertibility is achieved through specific tools rapid change, so that it is possible to set easily the mix model level on the same equipment or line.Major factors influencing cost: specific equipment and tools depreciations, maintenance and materials handling cost. Overall equipment efficiency and utilization level. Painting Painting process is a continuous flow process and each process are sequenced. We can divide it into two categories: 1) pre-painting treatments. 2) painting. 1). In reference of automazation and flexibility, the pre-painting process is not strictly relevant b ecause, for example, processes such as washing, degreasing or phosphating are not robot intensive, they actually are continous flow process with only a few operations.And each type of BIW(in our plants, refer them as type A and type B) can be processed in the same way with the same time, temperature and many other conditions. 2). The painting process is robot intensive because it is applied by automatic robots with electrostatic spray, along with automatic controlled air, temperature and humidity inside the painting booth. This process is relatively complex and harmful to human body. So in case of mass production, no labor force is enrolled in this process.Flexibility: Since equipments and tools are not specifically developed for each type of car, flexibility can be easily obtained by changing the process automatization software. And customized order-to-make product is mainly reflected in this process. Controlling program should be adjustable in order to change the color of the car easily. Major factors influcing cost: specific direct material(dye) and energy consumption, manpower necessary to manage the process and equipment maintenance costs. Final Assembly In terms of final assembly, manpower accompanied by flexible conveyor system is needed.This process is mainly labor intensive because many complex operations, such as cockpit module, steering leverages, seats and mobile parts are performed by technicians, but not machines. Certain level of automatization is required for simple operations such as joining, mechanical groups screwing and fixed glasses application. Moreover, ergonomic is important for labor intensive operations, so that assembling stations and conveyor systems have to be comfortable for the operators. For example the tow conveyors is an ergonomic solution for screw drivers.It can lift up the heavy body from BIW, to make the operator reach the lower part of the body. Recently new type of tow conveyors became more convenience since they allow t echnicians to stand on them and move along the operation line. Flexibility: product models mix along the final assembly line, thus flexibility can be obtained by high level of logistics and organizational complexity, which must use modern product and process information technologies, called â€Å"digital factory†. Moreover, â€Å"just in time† principle must be applied in supplying subassembly modules to the final assembly line.Major factors influcing cost: direct manpower, material handling, specific logistic information technology systems. 1. 4 â€Å"make or buy† decision In evaluation of make or buy decision, several factors should be considered: ITEMS FOR â€Å"MAKE† DECISION| ITEMS FOR â€Å"BUY† DECISION| 1. Availability of development capacities inside the company, at least equivalent to the one offered by External suppliers. | 1. Not availability of specific â€Å"know how† to develop in a competitive way the specific component or se rvice. | 2. Better protection of company’s know how in relation to products/processes considering core business| 2.Availability of reliable suppliers for the components or services required, in relation to the company’s targets. | 3. Needs of internal processes integration by logistic flows and final product quality level improving. | 3. Availability of alternative supplying sources in the geographical areas of strategic interest for the company. | 4. Not valid alternatives to component or services purchasing. | 4. Opportunity to simplify internal production processes and focus production resouces (man power and capital) on â€Å"core business†| 5. Necessity to utilize existing productive capacities inside the company. 5. Opportunity to reduce company owned investment by using or incrementing supplier’s productive capacities avaliable, assuming them the risk of volumes depending on the trend of market. | ITEMS FOR â€Å"CO-MAKERSHIP† DECISION| 1. N ew necissities of production capacities developing but not enough economy scale to proceed in an autonomous way. | 2. Partners have common or complementary interest in developing in a synergic and competitive way the new solutions required to guarantee the industrial mission. | 3. Partners have at disposal complementary or synergic technological capacities so that roduct/process innovation could be speed up without incrementing too much economical investments. | In genaral, an assembly plant doesn’t manufacture the sub group components of the car, for the sake of lean production, technology concentration and cost minimization. So no matter whether they are outsourced or manufactured by the same industrial group of other plants, we can consider them â€Å"buy† parts. It is easy to explore these elements from the vehicle systems point of view: All above mentioned elements and systems are out-sourced and they are assembled into higher level subassemblies aside the princip le assembly line.These elements and systems are based on evolutive technical solutions, which â€Å"know how† belongs generally to specialized companies components producers; A strong cooperation between those companies and car makers is necessary in case of technical projects development and experimentation and homologation on vehicle phases. 2. Review of tutorials and further applications of the tutorial 2. 1 General knowledges aquired from the assembly lecture During the assembly technology course, we gained the concept of automotive final assembly and aquired some basic knowleged about this process.First of all, the difinition of automotive final assembly can be concluded from the lecture: the final manufacturing process joining all of the finished subgroup components and modules to finish the car and make it functionlized, through different stages of assembly process with the right consequence. The final assembly process should consider from both management point of view and technological point of view: management concerns main subassembly groups and modules Here we consider the assembly of only these components in order to simplify the process.Also, some subgroups assembly are introduced in the lecture, which are normally performed inside the final assembly shop but not on the principle line. These sub-assembly parts should be considered since they are not out-sourced but manufactured inside the plant—stamping shop. So we won’t get the finished, assembled parts until we assemble them by ourselves, inside the final assembly shop. Along with subgroups assembly, ergonomics concern is introduced, which is a non negligibly problem in setting up the plant. Ergonomic: a). A study of the relation between people and their work environment. b).Is used to prevent injuries and illnesses associated with the design of physical work. c). Is used to increase employee safety and comfort and to optimize work performance and quality. Due to the complex ity of the system and inconvenience caused by the huge weight of the body in white and finished parts, ergonomic problem is closely related with the working stations and carrier systems that we use. Thus each process of the system uses specific equipment to orientate the car body in the right direction to technicians, and specific tools to hold finished parts to let technicians move them easily. ow conveyors let the installation of suspension more easily Moreover, the right sequence of final assembly is introduced. I will strictly follow this sequence to develop my assembly shop, because any mistake in sequence makes it impossible to build up later steps and lead the entire process to failure. Then I will build up working time analysis. 2. 2Extension of the tutorial 2. 2. 1 product breakdown structure(PBS) ; bill of material(BOM) Product breakdown structure is hierarchical and can be represented by the following scheme(tree diagram) F A B1 B2 C21 C13 C12 C11 E D F A B1 B2 C21 C13C12 C11 E D In which: A=final module (a car) B=1st level subassembly (powertrain, suspension system†¦) C=2nd and 3rd level subassembly (complete engine, transmission†¦) D=completed elements (cylinders, engine shafts†¦) E=partially completed elements (pistons, valves†¦) F=raw materials Using PBS, it is possible to: a). Manage the designs and standard carry-over solutions with other product lines. b). Underline links between elements, subassemblies and final product. c). Precise â€Å"make or buy† decision for each element. d). Activate manufacturing engineering plan for â€Å"make† parts. ). Activate purchasing orders for â€Å"buy† parts. f). Confirm cost for module components, considering the targets defined in the setting phase, according to the purchasing management system. Now let me define the PBS of the final assembly. I won’t list the lower levels of subassembly parts because the final assembly area is responsible for assembling mo re than 3000 in/on the painted vehicle shell, and if I focus too much on the minor parts, it would draw the attention away from the study of the system. Also, I extend the content of PBS, to get a bill of material table, more detailed. . 2. 2 work breakdown structure The work breakdown structure is a tree structure, which shows a subdivision of effort required to achieve an objective. In order to reach the WBS, I need to analysis each working processes first. The following figure is what I have obtained from the internship report. All of the data in this figure is roughly estimated, but the sequence and layout of final assembly is expressed. Final assembly process can be functionally divided into: trim line assembly, chassis line assembly, final assembly and final testing. ). Trim line assembly This station is focused on installing the following main components: the electric wiring and harnesses, the shell insulation and radiator insulation, the air duct system, the headliner, the c ondenser sub-assembly, the pedal sub-assembly, and the fire wall insulation. Other parts are also installed in this station such as the wiper links and the washer tank and its hoses and connections. To install the above described parts, a different conveyor system is adopted from the ones used in the paint area.So the shell is transferred from the paint-line conveyor system into typically a double rail chain or self-moving conveyor (floor-mounted), the elevation and speed of the body-shell are adjusted so it suits the production workers and allow them spatial access and enough time to complete the job. Some manufacturers have adopted a moving belt system for the line workers so that they can keep up with higher production rates. The first step in the trim assembly area is to remove the shell doors to facilitate the installation process, so large fixtures can be used inside the shell to aid the workers.The removed doors are hung on an overhead conveyor system that keeps running the d oors through the plant without any value being added to them. A typical layout for the trim assembly area can be shown as following: b). Chassis assembly The chassis assembly area is also called the marriage area, where the power-train of the vehicle is coupled with the vehicle body-shell. To achieve this, the vehicle shells are transferred to an overhead conveyor system to permit the chassis installation from the bottom. The assembled ower-train components are supplied from a sub-assembly area typically called the engine-line assembly area. The engine-line area features all the steps needed to install the different hoses, controllers and cables to the main engine body, in addition to coupling the engine to the transmission and the torque converters. The engine sub-assembly utilizes different types of conveyance depending on the accessibility needed, the station’s configuration (left- and right-side workers), and the weight of the assembled power-train; typically a combinatio n of an overhead system and an AGV(automatic guided vehicle) is used.The final assembled power-train is then mounted onto an AGV or a trolley equipped with a hydraulic lift, and then shipped to the marriage area. overhead conveyor and trolley with lifter In the marriage area, the vehicle shell will be synchronized with the AGV so both meet at a specific location that features the power torque machine that will use bolts and fasteners to join the power-train and shell together. Additionally, the elevation of the suspended shell is programmed according to specific settings to facilitate the mounting process. The powertrain is lifted via the hydraulic lift to meet the stationary shell.This process sequence is shown in the above figure. Several features within the vehicle shell are typically used to guide the power-train assembly to ensure its location and orientation within the vehicle; some laser projection-based sensors might also be used to ensure accurate placement. In addition, po wer-tools with built-in torque sensors are used to ensure fault-proof operation. Applying the right torque is essential in delivering mechanically sound joints that will not fail or fatigue due to under-torque or over-torque conditions. A typical layout for the chassis line assembly area can be shown as following: | ). Final assembly and testing area The final assembly area features the vehicle shell on tires for the first time. It is connected to the previous chassis assembly process, and each chassis assembly line can feed two final assembly lines. Thus for the sake of maximum utilization of the entire system, we set two final assembly lines. Each final assembly line is divided into three sequential parts: 1st. In the first part, preassembled bodies are put on a stop and go conveyor system, to facilitate the transferring from one station to the next.And the bodies are arranged across the axle of the line, to facilitate front-end module assembling and to keep operations such as ele ctric battery connections, air filter connections ergonomically. In this part fixed glasses are also assembled by automatic systems. 2nd. In the second part, car bodies are put on continuous double slat conveyor. Here, parts such as seats, garnishes, door modules, lighting systems and the rest parts of the vehicle are assembled. 3rd. In the third part, underbody operations such as adjusting the vehicle suspension and adjusting steering wheels are performed.After the assembly is complete, the completed vehicle starts the testing phase, where the following tests are conducted: alignment tests for wheels and turning radius, headlight test, side-slip test, engine drum test, and the brake test. The alignment test focuses on adjusting the wheels through the manual adjustment of the top of the front and rear wheels and the camber of the front and rear wheels. Further alignments ensure that the steering wheel is positioned accurately. The alignment test is typically done in a chassis dynamo meter chamber, shown in the figure. a chasis dynamometerAdditionally the turning radius can be tested and adjusted by measuring the right and left turning angles of the front wheels. The headlight test evaluates the photometric axis of the headlamps by projecting them on a screen and then measuring any deviations. The drum test is conducted by driving the vehicle into the chassis dynamometer to check the vehicle driving conditions. Also, the brake test evaluates the brakes’ performance by applying and measuring the braking force of each wheel (drag, service brake, parking brake). Finally, I can obtain the WPS from the integration of each above process. 3.Time analysis and relative calculations 3. 1 working time analysis(takt time, number of workers) In order to analysis the working time, I shall introduce the concept of takt time first. The takt time is the time that must pass between two succeeding unit completions in order to meet the demand, if the products are produced on e unit at a time, at a constant rate during the net available work time. The value of the takt time drives the key design choices for the assembly system. The takt time is defined in equation (1). (1) When the takt time is known one could decide how many assemblers and stations that are needed.It is quite hard to determine the number of assemblers needed in order to complete a product but here one basic method is presented. After the number of assemblers has been decided the number and layout of processes can be decided. The minimum number of assemblers can be calculated with equation 2. (2) If for example a product takes 100 minutes to assemble and the takt time is 1 minute, the process needs 100 assembler minutes every minute, consequently 100 assemblers. The formula does not take into consideration other activities that the operators perform apart from assembling such as picking and handling.A production system is also dependent on support labor which will of course increase the number of assemblers needed. When one has determined that the process is in need of 100 assemblers, the next step is to decide in which way the work should be allocated between the assemblers and thereby which method of assembly that should be used. On the one hand, one operator could work with one product from start to finish for 100 minutes. On the other hand, the total work content could be divided into 100 operations each taking 1 minute to perform.Now that the takt time concept is clear, I will start to analysis this according to my specific system. Actually, the first step in designing an assembly system is to calculate the takt time. I will calculate the takt time following these conditions: 1). The demand for daily production volume is 1300 units. 2). The system is operated by 3 shifts of operators. 3). The working hours per day for an operator are assumed to be eight hours. 4). Total downtime including scheduled and unscheduled maintenance, set-up times, breaks, lunch time is one hour per day.Takt time = Net avaliliable working time per dayaverage damand per day = 3*8-1*601300 = 0. 97 minute = 58 second The planned cycle time will be lower based on that there are inefficiencies regarding manpower issues and overall equipment effectiveness: Planned cycle time = 58*0. 85*0. 9 = 50 second Then the minimum number of workers can be obtained, under the assumption that the total assembly time (adding the time deeded of each operation in each station, i. e. : the labor time required in order to finish the assembly of a single vehicle) is 21 hours (empirical).We can assume that each operation is processed by an assembler because the final assembly is a labor driven process. No. of workers = total assembly timetakt time = 21*60*6058 = 1304 Thus, we have 1304 workers and if two workers are assigned to each work station, then we have 652 stations. Due to impossibilities for further analysis of working time, I can not get exactly the cycle time of each operation, but the time analysis methodologies should be stressed: a). Stopwatch study analysis For time measuring it is necessary to proceed as follows: 1).Workers are preventively trained to apply working standards and are informed about stopwatch study analysis and ways to proceed. 2). By statistical criteria, the number of operative cycle to observe is determined, considering also dispersion phenomena of analyzed process. 3). For each one of the macro-phase of operative cycle, time employed is recorded. 4). Working speed is punctually compared to the normal one, introducing eventual adjustment. 5). Time adjustments(increasing) for each working phase are applied following specific tables, to consider tiredness and physical efforts taken on during working shift.Applying the methodology is possible if the analyst is concerned about technologies of analyzed phases, in order to ensure in advance that working conditions follows manufacturing engineering plan, and proposing eventually necessary i mprovements. He must also observes movements considering ergonomics, defining normal and sustainable working speed. This evaluation implies also the application of specific rules related to physical efforts, tiredness, working positions and movements repetition.As a consequence, for each working phase analyzed, it is applied a time increasing coefficient, according to a standard table, elaborated on statistical and scientific considerations, by International Rules Institutions, with ergonomic, physiology, and working means experts associated. In case of uncertainty of working speed estimation, the analyst could perform observations on different subject, up to reach a calibrated evaluation. Furthermore, he can also use some available database, according to previous consolidated experiences.For each group of operations, it is important that the experts separate active times from inactive times necessary for machine/equipment waiting or movements between different working stations. Act ions to be adopted are related to inactive phases, that are not adding value phases. b). Time studying with modern techniques Same criteria of the first one, with the only difference that time observations are performed through video recording cameras, appropriately positioned and remote controlled, that allows measuring contemporary more operations, relating each other. c).Analysis with pre-determined standard times MTM technique (Methods Time Measurement) consists of previously analysis that allows quantifying time necessary for each working micro-phase included in the operative cycle. Measurements are performed in office and are very precise and objective. Application requires a big effort in terms of analyst technician, with high cost and long elaboration times. For this reasons MTM technique fits with widespread repetitive operations. d). Instantaneous Observations Analysis It fits for auxiliary operations only, including office operations.It is necessary that the analyst have good knowledge about function and roles of observed employees. He performs periodical inspections In the interested area and with established route by statistic method, so to cover all workplaces. He must evaluate: if workers are on their own workplace/if they are active/type of operation performed/type of tools used. 3. 2 system length and area calculation I will roughly calculate the length of the final assembly line. I say â€Å"roughly† because I will assume the distance between each product is 5m, and this distance is constant for all the three major processes belonging to final assembly.Although this assumption couldn’t be precise, this approach can represent the right process to calculate the system length. Firstly I will calculate the speed of the line: Speed = distancetakt time = 5m/58s = 0. 087 m/s Then I will apply this speed to the total assembly time: Length=speed*total assembly time=0. 087m/s*21*3600=6577m Finally, I should apply an modify coefficient, be cause large portion of the system paths are built for transferring, not value adding. 6577*150%=9865m Once the length is calculated, I can apply it to the width of the line, which is hypothesized to be 10m. 865*10=98650m2 And finally the subassembly line area should be calculated according to the same method, and added to the main line area. 3. 3 facility layout In arranging the plant layout, There are a lot of benefits: 1. Minimize the production time. 2. Minimize the production cost. 3. Minimize the material handling, in terms of time, cost and equipment type. 4. Minimize the investment in the equipment. 5. Utilize existing space more effectively. 6. Maintain flexibility of arrangement and operations. There are three basic types: process layout, product layout, and fixed-position layout.According to the selection criteria, I will choose the product layout. A product layout (also called a flow-shop layout) is one in which equipment or work processes are arranged according to the pr ogressive steps by which the product is made. The main issue over the final assembly line is the assembly line balancing. As we use the conveyor systems to carry the product, the time interval the product will stay in each workstation is identical, thus the cycle time of each workstation is identical as well (= 58s in our system).At each workstation, work is performed on a product either by adding parts or by completing assembly operations. The work performed at each station is made up by many bits of work, termed tasks, elements, and work units. The total work to be performed at a workstation is equal to the sum of the tasks assigned to that workstation. The assembly-line balancing problem is one of assigning all tasks to a series of workstations so that each workstation has no more than can be done in the work- station cycle time, and so that the unassigned (that is, idle) time across all workstations is minimized.The problem is complicated by the relationships among tasks imposed by prod- uct design and process technologies. This is called the precedence relationship, which specifies the order in which tasks must be performed in the assembly process. The steps in balancing an assembly line are straightforward: 1 Specify the sequential relationships among tasks using a precedence diagram. The diagram consists of circles and arrows. Circles represent individual tasks; arrows indicate the order of task performance. 2 Determine the required workstation cycle time, the same as takt time Determine the theoretical minimum number of workstations required to satisfy the workstation cycle time constraint using the formula, the same as the number of workers calculation. 3 Select a primary rule by which tasks are to be assigned to workstations, and a secondary rule to break ties. 4 Assign tasks, one at a time, to the first workstation until the sum of the task times is equal to the workstation cycle time, or no other tasks are feasible because of time or sequence restr ictions. Repeat the process for Workstation 2, Workstation 3, and so on until all tasks are assigned. Evaluate the efficiency of the balance derived using the formula Efficiency=sum of task timesactual number of workstations*workstation cycle time 6 If efficiency is unsatisfactory, rebalance using a different decision rule. Example: This table shows typical chassis assembly sequence of a car, and I will draw a precedence graph according to this table: Then, we can calculate the minimum number of workstations required: no. of workstations=45+50+11+15+9+12+12+12+12+8+958 = 4 So we can arrange the precedence graph accordingly: And the final Efficiency=1954*58=84%It can be seen that in station 4, only 9 seconds are employed among 58 seconds available time. To reduce this inefficiency, some independent operations can be added to this station. In this final assembly shop, we should analyze the work of all workstations, one by one, and reach a balanced assembly line finally. 4. Tool and eq uipment selection The final assembly area is considered a labor-driven process due to the high labor value-added work compared with other stations in the assembly plant. In this case, the right solution for labor and machine corporations is the key successful factor.Trim line: For the trim line assembly, the conveyor system should be changed from the one used in the paint line. We use the floor-mounted conveyor for the trim line and specially, I want to stress that since the plant should has a high production capacity, I choose to add an additional moving belt system to facilitate the workers for the high production rate. Moreover, for operations that will move heavy parts(doors, cockpits, windshield†¦), automation robots are selected instead of human labor. Robots are faster and more precise in installing heavy and big parts than human labor.For wirings, insulating applications, fuel tanks, steering leverage and etc. , I will choose to use human labors because these operations are too complicated for robots, and some area are deep inside the body shell and intangible for robots. On the other hand human labors have the advantage of agility, allowing them to go inside the body shell. In addition, batter-driven screwdrivers(low and medium torque models) should be equipped by the assemblers, to allow them fast and accurate fastening. Here are some pictures of the above mentioned tools and equipments: loor-mounted conveyor with moving belt Chassis line: For the chassis line assembly, the overhead conveyor system is needed to lift the vehicle shell and thus allow the installation of the powertrain system. In order to guide the pre-assembled powertrain system, the AGV(automatic guided vehicle) is used. At the same time battery driver screwdrivers and electric torque wrenches with torque limiters are used by workers to assemble the body and the powertrain system. Also, in order to ensure accurate placement, some laser projection based sensors are needed.Then the installation of wheels and exhaust system happens simultaneously. On the one hand line workers install exhaust system with the help of carrying robots. On the other hand multiple torque wrenches tightens the wheel. Of course tires must be handled with the help of the handling equipment in order to save time for the line workers. This process can spares much time for the powertrain assembly. The overhead conveyor system and the AGV. A multiple torque wrench is fast and precise A electric torque wrench with limiter A tire handler   Final assembly line:The vehicle is coupled with tires now, so a double slat conveyor system is selected to carry the body. In addition, a variety of arm and drop lifters are needed for the ergonomics consideration. Also, fluid filling machines is crucial in this stage: fuel tank, engine, transmissions†¦ For the testing phase, we need testing machines. For example the chassis dynamometer is necessary for the alignment test, the turning radius test an d the break test. The headlight test evaluates the photometric axis of the headlamps by projecting them on a screen and then measuring any deviations.A double slat conveyor A chassis dynamometer A seat handling partner References: 1. COZZARI GIULIANO, Assembly technologies,2010. 2. MARCO GOBETTO, Production Management,2010. 3. Mohammed A. Omar, â€Å"THE AUTOMOTIVE BODY MANUFACTURING SYSTEMS AND PROCESSES†, 2011 4. FILIP HELLMAN, BJORN LINDAHL, JONAS MALMBERG, thesis of â€Å"Mixed-model assembly line at Volvo Construction Equipment† 5. Marshall L. Fisher and Christopher D. Ittner, â€Å"THE IMPACT OF PRODUCT VARIETY ON AUTOMOBILE ASSEMBLY OPERA TIONS: ANAL YSIS AND EVIDENCE† 6. technical note five: FACILITY LAYOUT

Tuesday, October 22, 2019

Fifth Meditation essays

Fifth Meditation essays In the Fifth Meditation by Rene Descartes, he makes a case for the existence of God. He goes on to give reason to prove his argument that to exist is to believe in God for with out God we would not exist. Descartes gives the analogy of a mountain and a valley, pointing out that if a person believes that a mountain exists they cannot deny the existence of a valley, as stated in this quote: From the fact that I cannot think of a mountain without a valley, it does not follow that a mountain and valley exist anywhere, but simply that a mountain and a valley, whether they exist or not, are mutually inseparable. Descartes states the argument here, But from the fact that I cannot think of God except as existing, it follows that existence is inseparable from God, and hence that he really exists. Then he goes on to explain his reasons for the existence of God, It is not that my thought makes it so, or imposes any necessity of the thing itself, namely the existence of God, which determines my thinking in this respect. For I am not free to think of God without existence. He is saying, without God he would not exist, and if he does not exist he cannot think therefore God must exist if he has the ability to think. He supports his arguments further, as we see here, Descartes gives his conclusion, it states, I have perceived that God exists, and at the same time I have understood that everything else depends on him, and that he is no deceiver; and I have drawn the conclusion that everything which I clearly and distinctly perceive is of necessity true. He is saying, first of all, that everything that he unmistakably understands is true; he clearly understands God, therefore God exists! To support his conclusion he gives the argument, even if I am no longer attending to the arguments which led me to judge that this is true, as long as I remember that I clearly a ...

Monday, October 21, 2019

Napolean Bonaparte1 essays

Napolean Bonaparte1 essays Napoleon Bonaparte was born in 1769 on the small island of Corsica in the Mediterranean Sea. He was born at a very hectic time. Corsica was trying to gain independence when French troops invaded. He was born during a war, and hell die because of one. When he turned ten his parents sent him to a military school just outside of Paris. He devoted himself to learning and gaining experience to military tactics, it paid off. When he was 16 he became a lieutenant in the artillery. Revolution broke out the same year. He joined the military of the French Republic. In October of 1705 a government official told Napoleon to defend the palace where the National Convention took place. He, with his small army, defeated the thousands of royalist in minutes. He is declared a hero. In 1796 the Directory appointed him to command a French army. He marched into Italy and liberated it from Austria, although some say he conquered it. The Directory wasnt doing very well. In 1799 it accused the French people of being corrupt. Napoleon seized this opportunity to take it over. On November 9, 1799 he and 500 soldiers took over one chamber of the National Legislature and drove out the members. The second chamber voted to end the directory. France was now in the hands of three officials, called consuls. Napoleon was one. In 1800, he and his fellow consuls set up the plebiscite in which the citizens had the right to vote yes or no on an issue. On December 2, 1804, Napoleon crowned himself emperor. The plebiscite made this so. The Pope crowned him himself. People thought he was a godsend. He greatly changed the economy of France by making a lot of reforms. He set up a bank, let emigres back into France, he let their be freedom of religion, he freed slaves, and set up the Napoleonic Code. The people outside of France thought differently about Napoleon. They hated him. ...