• Journal of Advanced Marine Engineering and Technology
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• v.13 no.1
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• pp.57-68
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• 1989

This paper treats the analytical and experimental studies on the improvement of commutating circuit for the speed control of DC motor. A simple circuit composed of R, L and C elements is proposed here for switching off power SCR carrying the load current. The real important in this chopper circuit is to determine the reasonable values of commutating circuit constants. In this paper, the reasonable values of the commutating circuit constants are basically determined on a view point of commutating performances in the given circuit model and must satisfy the following conditions. The first, the peak commutating current should be larger than the anticipated maximum load current. The second, the circuit turn-off time (tc) must be longer than the SCR turn-off time (tq). The third, the resistor should be enough large to permit the current to be neglected in the analysis of the commutation circuit, as well as be enough small to permit to charge the capacity voltage (Ec) to the half the value of source voltage (E) before the next communication cycle is initiated. The last, the period of chopping signal must be the least possible multiple of the damping vibration period of commutating circuit. The improved chopper circuit used in the experiment under unloaded condition was composed to meet the reasonable conditions mentioned above, and a successful commuting performance was achieved without failure. Several types of microprocessor having a different value of CPU speed individually have been applied to the experiment under the loaded conditions. Also it shows that the faster the speed of CPU is, the more stable the commutation turns out.

• Journal of Information Technology Services
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• v.14 no.2
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• pp.69-86
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• 2015

The current contract awarding process regulated by laws and ordinances is analyzed and more reasonable processes are suggested. To this end, the principle of economic analysis is described with emphasis on the cost-effectiveness analysis, and the laws and ordinances regulating the process are thoroughly examined. The current contract awarding rule is based on the weighted sum of effectiveness score and cost score. This may not conform to the framework of economic analysis where effectiveness is supposed to be measured as an output and cost measured as an input. An improvement is attempted to the defense acquisition system and it is recognized that the economic analysis and policy consideration should be performed separately. Concept of statistical testing is introduced to see if the results of the cost effectiveness analyses show the significant difference between the alternatives. It is suggested that the contract awarding process can be improved by performing significance test followed by the aggregation of the two analyses. A minor improvement is also suggested on the application of current rules.

• Asia-Pacific Journal of Business
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• v.14 no.2
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• pp.101-118
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• 2023

Purpose - The purpose of this study is to find out how a company can do reasonable cost calculations in a simple way and establish profitability improvement strategies based on the results. Design/methodology/approach - In this study, a case that compounding company K applied TDABC was studied. A case study was conducted on the process of company K reviewing and applying TDABC and the process of implementing the cost calculation for each product by applying TDABC, and establishing a profitability improvement strategy for each product based on the results. Findings - Company K rearranged the production standard information of the compounding industry such as productivity and batch size of each product to apply TDABC. Cost calculation was performed for each product according to the revised production standard information. After the cost calculation for each product was carried out, Company K established a strategy to improve profitability of each product. The profitability improvement strategy was implemented in two ways: a cost reduction strategy and a product price increase strategy. As a result of the final strategy execution, the profitability of each product was improved. Research implications or Originality - This study found a reasonable costing standard in consideration of the specificity of the research target company, and applied it to cost calculation cost for each product. It contains the process of establishing production and sales strategies for each product based on the cost calculation results. It is expected that this case study will serve as a good reference material for establishing cost calculation and profitability improvement strategies in similar businesses.

• Journal of The Korean Radiological Technologist Association
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• v.25 no.1
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• pp.24-24
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• 1999

In order to establish reasonable concept and background on repititive films, we analyzed factors due to wasted films grouping into three major factors as 1) artificial factor from exposure and positioning. 2) mechanical factor as mechanic error and jammin

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.4
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• pp.467-473
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• 2013

The addition of disconnect switches to a distribution feeder or the replacement of the manual switches with the automatic switches do, in general, increase reliability by decreasing the duration of the outage of many to the customers on the feeder and reducing the outage section. However, the improvement of reliability in power distribution system causes an increase of the investment cost, for example, replacement costs, labor costs, and so on. For this reason - the balance between investment and reliability improvement - many studies about the appropriate level of investment have been conducted. In this paper, we suggest the algorithm for determining the reasonable switch automation rate in the power distribution system. We evaluate the customer interruption cost and reliability for several cases - these cases relate with the switch automation rate - in the domestic metropolitan power distribution system, estimate the effectiveness of changing the manual switch to automatic switch quantitatively. These results can help the determining on the disconnect switch's automation rate.

• Journal of Advanced Marine Engineering and Technology
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• v.11 no.3
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• pp.31-44
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• 1987

Nowadays, the problems of energy and environmental pollution become serious day by day and the diesel engine, which has been proved to be superior to gasoline engine with respect to fuel consumption and ecological problems of exhaust gas, has been adopted widely for various purposes from the marine diesel engine and the dynamo engine to all kinds of engine on land. Therefore, extensive parametric studies on combustion of diesel engine should be done for its desing and improvement. To predict the behavior of diesel engien according to variable operating conditions by means of cycle simulation, the reasonable pattern of heat release rate has to be asumed. But it is necessary to know the actual variation of heat release rate in order to assume the reasonable pattern of heat release rate according to the actual operating conditions. In this paper, on a high speed small bore diesel engine with pre-combustion chamber, experimental investigations were carried out to determine the relationship between the heat release pattern and parameters such as engine load and speed. And also, the theoretical investigations about the performance variations of the above diesel engine according to the predicted pattern of heat release rate variation were performed. From the above observations, it may be said that the Fanboro indicator, which was used to get the cylinder pressure, can be used to estimate a reasonable pattern of heat release rate and it is confirmed that the pattern of heat release rate for the pre-combustion type engine is different from that of the direct injection type engine.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1316-1323
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• 1999

Extensive emphasis on milk and milk fat yields with no diversion for beef performance increased the yield efficiency of North American dairy cattle. Heavy demand for North American genetics followed national strain comparison trials in Poland, and US and Canadian dairy cattle and germplasm still are an important source of genetics for many countries. Genetic improvement has accelerated in many countries because of the implementation of sampling programs for young bulls and improved evaluation procedures. Rapid access to information and more frequent calculation of genetic information also are having a positive impact on genetic improvement. Traits other than yield should be considered in a breeding program, but those traits mist have a reasonable opportunity for improvement and sufficient economic worth. Because of ever increasing efficiency, the world's milk supply comes from fewer cows each year. However, no decline in the rate of genetic improvement is apparent under current genetic practices; estimates of heritability are increasing, and a decline in yield efficiency is unlikely in the near future. As management improves, especially for subtropical conditions, many of the selection principles used in temperate climates will be adopted for more adverse environmental conditions.

• Journal of the Korean Professional Engineers Association
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• v.27 no.6
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• pp.85-93
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• 1994

For the continuous development of the manufacturing company, selp-helpㆍdiligence of the individual members of the organization and cooperation system of the sub-department process of the manufacture must operate under rationality. Moreover, perpetual and reasonable improvement on productivity should be focused on. Improvement on productivity implies raising $\ulcorner$output / input$\lrcorner$ ratio, and this does not only implies simple increase of the level of output. Therefore under the theoretical principle, Which is designed to increase the ratio of $\ulcorner$output / input$\lrcorner$ -economically select the relevant $\ulcorner$methodology$\lrcorner$. When rational improvement on productivity $\ulcorner$techniques$\lrcorner$ are properly applied with this methodology, calculated result will come out. The ultimate aim of improving quality does not mean simply reducing the percentage of the defects, but means improving the quality of products, for customer satisfaction. Thus recognize this, we have to contribute to the national economy growth through the enhancement of added value of individual company by $\ulcorner$improvement on quality and productivity, and reduction of the cost$\lrcorner$, $\ulcorner$improvement program on quality and productivity$\lrcorner$ shouldn't be just the parading formality. We can expect the economy result, these are applied to the learning essence and the principle of the improvement.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.44
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• pp.207-215
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• 1997

This paper deals with a comparison between Taguchi's accumulation analysis method and Nair test on the ordered categorical data from an industrial experiment for quality improvement. a result of Taguchi's accumulation analysis method is shown to have reasonable power for detecting location effects, while Nair test identifies the location and dispersion effects separately, Accordingly, Taguchi's accumulation analysis needs to develop methods for detecting dispersion effects as well as location effects. In addition this paper rewmmends models for analyzing ordered categorical data, for examples, the cumulative legit model, mean response model etc Successively simple, reasonable methods should be introduced more likely to be used by the practitioners.

• Journal of the Korean Professional Engineers Association
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• v.36 no.6
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• pp.78-81
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• 2003

Physiologically functional food is a type of the processed foods showing bioactivities in a living body. Physiologically functional food is a healthy food reinforcing biofunctional abilities of the precaution and recovering of the illness, immunity reinforcement. bio - rhythm control, aging repression and cancer precaution, etc. The consumers are taking to expect the improvement of national health and extention of life span. etc., Physiologically functional food must be able to be ingested briefly and taken in the surroundings easily and the reasonable price. To achieve this goals, it is necessary to positive support of the authorities concerned, technique development of an educational - Industrial cooperation. establishment of reasonable standard and right understanding of the consumers on physiologically functinal food.