• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.110-118
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• 2015

The standard production unit system is the most basic element in our country construction. However, this standard production unit system shows a large difference in the actual amount of labor input for works at the Apartment housing construction, Therefore, it may be a reasonable alternative to estimate the cost of construction by historical cost data, works will be calculated the cost of labor must determine the exact amount and It is necessary to determine the exact amount of labor input for the construction progress management. This study examines the results of comparing the standard production unit system and the actual amount of labor counting in apartment housing construction was completed in the metropolitan area since 2000, the following results were obtained. the actual amount of labor input are looked for 1.184person/1000 of masonary, $0.084persons/m^2$ of plaster, $0.039persons/m^2$ of Waterproofing, $0.059persons/m^2$ of tile at the Apartment housing construction. in the actual amount of labor counting Compared with standard production unit system, masonry ratio of 59.8%, plaster ratio of 41.3%, waterproofing ratio of 31.5%, tile ratio of 34.3% and The labor rate in the works was the lowest in the plaster. was relatively high in the masonary. Therefore, the amount of labor country apartment housing construction is preferably calculated on historical cost data. But it seems that the amount of labor necessary complement ongoing close enough to the actual standard production unit system a major variable in construction management.

• Journal of the Semiconductor & Display Technology
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• v.17 no.1
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• pp.54-61
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• 2018

In this study, two aspects were analyzed about the robot for removal of explosive devices. First, the cost analyses were performed to provide a reasonable solution for the acquirement of the system. It is processed by an engineering estimate method and the process was consisted of two ways : a system development expense and a mass production unit price. In additions, the resultant cost analyses were compared between the cases excluding and including a mines detection system. As results, in the case of the acquirement of the robot system for removal of explosive devices, it is recommended that the performance by improving the mines detection ability should be considered preferentially rather than the cost because the material cost for the mines detection system is negligible compared to the whole system cost. Second, as a way for improving the system performance by the mine detection function, the carbon nanotube (CNT) based sensor technology was studied in terms of sensitivity and simple productivity with presenting its preliminary experimental results. The detection electrodes were formed by a photolithography method using a photosensitive CNT paste. As results, this method was shown as a scalable and expandable technology for the excellent mines detection sensors.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.259-266
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• 2011

Project owner, asbestos removal specialist, experts on asbestos removal work, as counter parts to be defined in the study to make out research goals have been asked with questionnaire survey and replied with 65, 275, 32 cases, respectively. And additionally, direct interview 73 sheets have been collected to find out current status of required engineers and equipments assigned and provided to the field, from them, three(3) concerned parties. Questionnaire subjects are composed of common items, reasonable unit cost, need of separate contract-awarding system, status of performing standard contract, status of providing legal engineers and equipments. Concentrated review of two~three questions by subject has been made to find out and compare idea results between three(3) concerned parties. First, legal and practical work status survey have been made to determine reasonability of introducing separate contract-awarding system, as a part of ensuring reasonable unit work cost. And then, two different status have been compared and there is introduction possibility of separate contract-awarding system, it is found out. The possibility of separate contract also has been confirmed by comparison of domestic legal grounds. Justificating grounds to introduce separate contract-awarding system have been shown. Standard contract status between asbestos removal specialists has been compared using two cases of providing removal work contract and receiving it. It is shown that case of 50 percent or less contains 38.5% when they receive contract, but only 10 percent reduction of original contract amount has been made when they provide it. It means that asbestos removal specialists do not keep occupational safety and health regulations.

• Korean Journal of Construction Engineering and Management
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• v.6 no.5 s.27
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• pp.186-192
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• 2005

The purpose of this study is to find the reality of environmental management cost in construction projects and to suggest some policies in order that owners appropriate the environmental management cost reasonably in the construction budget for reducing the environmental pollution at job sites. We surveyed the actual state of appropriating and expending the environmental management cost over 122 construction sites. According to the results of the survey, while the appropriated rate of the environmental management cost was 0.59% of the total construction cost. the expended rate reached at 0.94%. When examining the antipollution facilities which were operated in job sites, the investment for equipment against air-pollution such as tire washer, dust-proof device was relatively higher than other antipollution equipment. As the method appropriating the environmental management cost, we concluded that a quantity-per-unit costing method is more reasonable than appropriating at a fixed rate of total construction cost considering that there is little correlation between total construction cost and the environmental management cost. To do so, antipollution facilities that must be examined at a design or estimation stage of a construction project should be prescribed by the law. Moreover, referenced cost data for the quantity-per-unit costing should be prepared and officially published.

• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.50-57
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• 2009

The Korea Standard of Estimate which has been used as the only basis of Cost estimate of public construction projects is failed to reflect the fluctuation of current construction cost. Therefore, the government decided to gradually introduce historical construction cost into cost estimate of public construction projects from 2004 and to reduce the use of Korean Standard of Estimate. This paper presents a series of process and the methodology for computing Actual Cost and analyzing the fluctuation patterns based on not only previous contract prices which made a successful bid but also all of the other bid prices. Also, this paper mainly handles a device for extracting strategic bid price such as low price bid for assuring reliable data and for predicting the construction cost which is built by Wavelet Analysis of Time series Analysis data and Neural Network. It is anticipated that the effective use of the proposed process for estimating actual unit cost would make the cost estimation more current and reasonable.

• Journal of Advanced Marine Engineering and Technology
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• v.8 no.2
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• pp.51-66
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• 1984

The cost percentage of engine part in the total building cost of a ship is about 30-40% and the main engine occupies about 50% of the engine part cost. For certain ships the fuel bill can be as high as about 60-70% of the total operating cost after two oil shocks and its amount for one year is nearly equivalent to her main engine price. This fact has further increased the pressure on the engine builders to develop engines of higher efficiency and better possibilities to burn further deteriorated fuel qualities. But the energy-saving plants are ordinarily more expensive and their available amount of exhaust gas energy is less and therefore, they are not always profitable and optimum systems. This paper is prepared to decide the most economical and efficient engine systems by presenting reasonable selecting and economical evaluation methods of the main engine, which is the largest single unit and the most expensive, and its auxiliaries. In order to demonstrate the application of investigated methods in a practical case, a 46, 000 DWT class bulk carrier is selected as a model ship and her main engine and its auxiliaries are selected and evaluated. The result shows that the optimum determined has one year three months POP, 0.903 IRR at a year, 4, 116, 000 dollars PW in 15 years (for 5% escalation rate of fuel cost) and 9.522 BCR for same condition, when the engine plant of a same existing ship is taken as the basis.

• Elastomers and Composites
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• v.50 no.1
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• pp.1-6
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• 2015

Polybutadiene rubber (BR) has been well known that its physical and chemical properties are changed when it is exposed to ultraviolet light undergoing photooxidation. In this study, photooxdiation process of BR vulcanizate was investigated using a high pressure mercury lamp used as an outdoor lighting, which has high UV radiation efficiency and reasonable cost. Discoloration and crack formation of photooxdized BR vulcanite surface were examined using an image analyzer. Change of chemical functional groups of BR vulcanite surface by photooxidation was investigated using ATR-FTIR, and variation of the crosslink density with the UV irradiation time was investigated. By increasing the UV irradiation time, the crosslink density steeply increased after a period of time and did not increase any more. Formation of hydroxyl (~OH) and carbonyl (~C=O) groups on the BR vulcanizate surface increased and the1,4-cis unit was converted to the 1,4-trans unit as the photooxidation was proceeded.

• Journal of Korean Public Health Nursing
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• v.2 no.2
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• pp.21-44
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• 1988

In Korea, fee-for service reimbursement has been adopted from the begining of medical insurance system in 1977, and the importance of the relative value unit is currently being investigated. The purpose of this study was to find out the level of propriety of the difference in the fees for different surgical services, and the appropriateness of the classification of the insurance fee schedule. For the purpose of this study, specific subjects and the procedural methodology is shown as follows: 1. The propriety of the Relative Price System(RPS). 1) Choice of sample operations. In this study, sample operations were selected and classified by specialists in general surgery, and the number of items they classified were 32. For the same group of operations the Insurance Fee Schedule(IFS) classified the operations into 24 separate items. In order to investigate the propriety of the RPS, one of the purpose of this study, was to examine the 24 items classified by the IFS. 2) Evaluation of the complexity of surgery. The data used in this study was collected The data used in this study was collected from 94 specialists in general surgery by mail survey from November I to 15, 1986. Several independent variables (age, location, number of bed, university hospital, whether the medical institution adopt residents or not) were also investigated for analysis of the characteristics of surgical complexity. 3) Complexity and time calculations. Time data was collected from the records of the Seoul National University' Hospital, and the cost per operation was calculated through cost finding methods. 4) Analysis of the propriety of the Relative Price System of the Insurance Fee Schedule. The Relative Price System of the sample operation was regressed on the cost, time, comlexity relative ,value system (RVS) separately. The coefficient of determination indicates the degree of variation in the RPS of the Insurance Fee Schedule explained by the cost, time, complexity RVS separately. 2. The appropriateness of the classification of the Insurance Fee Schedule. 1) Choice of sample operations. The items which differed between the classification of the specialist and the classification of medical, Insurance Fee Schedule were chosen. 2) Comparisons of cost, time and complexity between the items were done to evaluate which classification was more appropriate. The findings of the study can be summarized as follows: 1. The coefficient of determination of the regression of the RPS on-cost RVS was 0.58, on time RVS was 0.65, and on complexity RVS was 0.72. This means that the RPS of Insurance Fee Schedule is improper with respect to the cost, time, complexity separately. Thus this indicates that RPS must be re-shaped according to the standard element. In this study, the correlation coefficients of cost, time, complexity Relative Value System were very high, and this suggests that RPS could be reshaped I according to anyone standard element. Considering of measurement, time was thought to be the most I appropriate. 2. The classifications of specialist and of the Insurance Fee Schedule were compared with respect to cost, time, and complexity separately. For complexity, ANOVA was done and the others were compared to the different values of different classifications. The result was that the classification of specialist was more reasonable and that the classification of Insurance Fee Schedule grouped inappropriately several into one price unit.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.434-438
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• 2012

Purpose: This study was performed in order to improve problems and to seek the efficient operating plan by surveying and analyzing the actual status of operating the agricultural machinery rental business supported by the government. Method: The data was collected through two times of survey targeting lease business operators and the leasing business reports published for the past 3 years ('08~'10) 120 cities and counties. Results: As a result of surveying 120 cities and counties nationwide of operating the agricultural machinery rental business, 96% of agricultural machinery rental businesses were indicated to be operated in the form of short-term rent for about 1~3 days centering on small-sized agricultural machinery and attachment for upland crop. As for the unit number of possessing rental agricultural machinery and the purchase cost, it was indicated to be greatly reduced the agricultural machinery for rice farming and to be expanded into upland crop whose mechanization is insufficient. The annual rental days ('10) are 9.5 days/unit, thereby being a little insufficient. Rental fee for 1 day is 0.2~0.8% of the initial purchase cost of agricultural machine, thereby being greatly lower compared to 2.0% (annually 10-day rent) of the proper rents, resulting in being demanded improvement. Conclusions: To be continuously driven the rental business of agricultural machinery with having the ability to propagate, it is judged to be likely to necessarily collect optimum rental fee in consideration of rental days as well as increasing the use days per unit by buying the agricultural machinery, which is secured the rental demand, and by possessing the reasonable unit number.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.410-415
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• 2009

With the implementation of electric power industry reform, the utilities are looking for effective ways to improve the economic efficiency. One area in particular, the equipment maintenance, is being scrutinized for reducing costs while keeping a reasonable level of the reliability in the overall system. Here the conventional RCM requires the tradeoff between the upfront maintenance costs and the potential costs of losing loads. In this paper we describe the issues related to applying so-called the "Reliability-centered Maintenance" (RCM) method in managing electric power distribution equipment. The RCM method is especially useful as it explicitly incorporates the cost-tradeoff of interest, i.e. the upfront maintenance costs and the potential interruption costs, in determining which equipment to be maintained and how often. In comparison, the "Time-based Maintenance" (TBM) method, the traditional method widely used, only takes the lifetime of equipment into consideration. In this paper, the modified Markov model for maintenance is developed. First, the existing Markov model for maintenance is explained and analyzed about transformer and circuit breaker, so on. Second, developed model is introduced and described. This model has two different points compared with existing model: TVFR and nonlinear customer interruption cost (CIC). That is, normal stage at the middle of bathtub curve has not CFR but the gradual increasing failure rate and the unit cost of CIC is increasing as the interruption time is increasing. The results of case studies represent the optimal maintenance interval to maintain the equipment with minimum costs. A numerical example is presented for illustration purposes.