• International conference on construction engineering and project management
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• 2005.10a
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• pp.1112-1117
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• 2005

Construction cost index is generally used to estimate the new project cost based on past construction data and to adjust contract cost when the price change of various articles and items of expenditure composing the contract occurs. In Korea, it is mostly used for adjustment of construction contract cost due to fluctuation of prices. However index adjustment rate which is used for adjustment of construction contract cost had some problems in calculating cost index of each expenditure item that could not reflect properly the change of construction cost. For supplementing these problems, the research of developing construction cost index has been executed. Through the precedent research, these problems were partially resolved but still remain. Therefore this research proposes method of making cost index that utilizes representative items of labor, material, and equipment by analyzing bill of quantity of road construction, through analysis and comparison of precedent study. By using this method, it is expected to solve problems which were not reflected in precedent studies.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.3
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• pp.243-252
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• 2015

This paper considers a supply chain consisting of a manufacturer under the cap-and-trade emissions regulation and a permit supplier. We study joint production quantity and investment in reducing permit production cost decisions for centralized and decentralized supply chains. We formulate two supply chain contracts with aims to coordinate the decentralized supply chain; wholesale price contract and cost-sharing contract. Under the cost-sharing contract, the manufacturer shares a part of the investment in reducing permit production cost and then is allowed to purchase emission permit at a lower price. We analytically find that the proposed cost-sharing contract with reasonable parameters can coordinate the supply chain whereas the wholesale price contract is not desirable to achieve the system-wide profit. Numerical example is followed to support the analysis.

• Management Science and Financial Engineering
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• v.15 no.1
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• pp.1-31
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• 2009

This paper considers the value of warehousing contract under probabilistic demands. We consider a supply chain consisting of a supplier, a retailer and its third-party warehousing partner who provides the warehousing service to the retailer through an outsourcing contract. A typical contract is specified by initial space commitment and modification schedule. The retailer decides the order quantity for the supplier and space commitment for the outsourcing contract. Since there is close relationship between order quantity and space commitment to minimize the total cost including ordering cost, inventory carrying cost, shortage cost, and warehousing cost, we develop an analytical model under probabilistic demands, where the retailer can determine the optimal order size and space commitment level jointly. We found the closed-form optimum for a single-period case and the optimal conditions for a two-period case. To evaluate the value of contract flexibility for the two-period case, we compared the total cost under two policies; one with modification, under which the base commitment can be changed at the start of each period and the other without modification. From results of our numerical analysis, we showed that the modification policy is more cost-effective as the variability of demand increases.

• International journal of advanced smart convergence
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• v.9 no.2
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• pp.157-163
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• 2020

Recently the blockchain technology has been actively studied due to its great potentiality. The smart contract is a key mechanism of the blockchain system. Due to the short history of the smart contract, many issues have not been solved yet. One main issue is vulnerability and another main issue is cost optimization. While the vulnerability of smart contract has been actively studied, the cost optimization has been rarely studied. In this paper, we propose two cost optimization methods for smart contracts running on the blockchain system. Triggering a function in a smart contract program code may require costs and it is repeated continuously. So the minimization of costs required to trigger a function of smart contract while maintaining the performance equally is very important. The proposed two methods minimize the usage of expensive permanent variables deployed on the blockchain system. We apply the proposed two methods to three prevalent blockchain platforms: Ethereum, Klaytn and Tron. Evaluation experiments verify that the proposed scheme significantly reduces the costs of functions in the smart contract written with Solidity.

• Journal of the Korean Dietetic Association
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• v.9 no.3
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• pp.197-208
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• 2003

This study was surveyed to provide the information on current operational practices and issues of contract-managed foodservice companies. Questionnaires were distributed to 79 contract-managed foodservice companies (eight large-size, 48 mid-size, 23 small-size companies) from March to May in 2002. The contract-managed foodservice companies provided averages of 269,184 (range 140,036-503,500), 14,837 (range 450-75,269), and 4,065 (range 930-8,050) meals daily from large, medium, and small-size companies, respectively. The companies managed to averages of 268.2 (160-619) foodservice contracts at large-size companies, 21.9 (5-63) contracts at mid-size companies, and 4.7 (1-10) contracts at small-size companies. The average numbers of dietitians were 298.6 (range 104-671) in large-size companies, 22.2(6-86) in mid-size companies, and 3.8(1-9) in small-size companies. The averages of sales were 156.5 billion at large-size companies, 6.7 billion at mid-size companies, and 1.7 billion at small-size companies in 2001. The contract was two types including management fee contract(5%), and profit and loss contract(95%). The cost ratios for office foodservice were 59.5% at food cost, 24.2% at labor cost, 6.3% at profit, and 10.1% at other cost. For hospital foodservice, the ratios were 54.0% at the food cost, 34.6% at labor cost, 3.0% at profit, and 11.8% at other cost. For high school foodservice, the ratios were 62.2% at the food cost, 21.5% at labor cost, 5.4% at profit, and 11.2% at other cost. When the contractors managed to the foodservice, the most important matters were the sanitation management and customer satisfaction. Also, the difficult problems were excess investment of equipments and low meal prices.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.510-514
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• 2004

This research is a preliminary one to investigate transitional problems of actual-cost-date-based contract cost estimation method and suggestions for counteracting them. As parts of it, in this paper, the brief background and methods of the new method and contract costs estimated by introducing it are presented. The results of five projects' contract costs are compared to those estimated by the conventional quantity-based method. Comparison of the both is conducted in terms of total contract costs and contract costs according to type of sub-contracts. Finally, the propositional differences of the later to the former are analysed.

• Journal of the military operations research society of Korea
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• v.37 no.1
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• pp.99-118
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• 2011

According to the National Contract Law, when determining Estimation cost Contract officers should consider contract quantity, contract period, supply and demand condition, difficulty of contract enforcement, terms and condition, and other various conditions based market price, costing based pricing, and appraisal. And they should not overestimate or underestimate the estimation cost. But the estimation cost system is used as preparedness for audit against the contract law. In this study, we identified the factors affecting estimation cost and analyzed their influence on estimation cost.

• Journal of the Korean Dietetic Association
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• v.10 no.3
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• pp.293-299
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• 2004

The purposes of this study were to : a) investigate the current status of contracted hospital food services, b) analyze and clarify various perspectives of contractors and hospitals. Thirty six hospitals and their contractors which were having more than 100 beds located in Seoul, Inchon and Kyungkido, were the subjects of this study. Data were collected through surveys. The survey was conducted during March to April in 2002. Questionnaires were mailed to the 36 directors of dietetic departments of hospitals and 36 managers of contract foodservice management company. Statistical analysis was completed using SPSS Win(11.0) for descriptive analysis, t-test and $x^2$-test. The results of the study can be summarized ; 1. The type of contract considered adequate by directors of dietetic departments and managers of contractors was fee-contract, combined type, followed by profit-and-loss contract. 2. According to the results from analysis on the contract cost per meal considered adequate by directors of dietetic departments and managers, the directors of dietetic department indicated that showing no difference with the current contract cost per meal. However, the managers of contractor indicated that showing significant differences compared with the current contract cost per meal(regular diet p<0.01, therapeutic diet p<0.001). 3. In the composition of contract cost per meal considered adequate, the managers of contracting businesses accounted labor cost (p<0.01) as a major cost, whereas the chiefs of nutrition departments accounted miscellaneous or controllable expense (p<0.001) and VAT (p<0.01) as major costs. 4. The directors of dietetic departments and managers thought that the hospital should be responsible for utility costs. On the other hand, directors of dietetic departments regarded that the contractor and managers thought that the hospital should pay for facility investment cost.

• Journal of the Korean Dietetic Association
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• v.9 no.2
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• pp.128-137
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• 2003

The purposes of this study were to investigate the current status of contracted hospital food services and to find out the difference in accordance with the number of beds in hospitals. Thirty six hospitals having more than 100beds in Seoul, Inchon and Kyungkido were the subjects of this study. Data was collected through surveys. The survey was conducted during March and April in 2002. The Questionnaires were mailed to the 36 directors of dietetic departments of the hospitals and 36 managers of contracting patient food services. Statistical analysis was completed using SPSS Win(11.0) for descriptive analysis and t-test. The results of the study are summerized as follows; Ⅰ. Hospital perspective : The range covered by contract food service was 63.3% and 36.7% in hospital food services, and medical nutrition services. The patient and employee food services were in 83.3%, and patient food services were in 6.7%. The methods selecting contractors are general, limited, selected and competitive biddings, and private contracts. The responsibility for supervision of contract food services was the dietetic department (51.7%) in most cases. Hospitals having personnel responsible for contracting affairs were in 75.9% of the cases and 24.1% did not have personnel. The biggest reason for contracting was facilitation of personnel management. The most important criteria on selecting food services contractors was the professionality of the contractor. Ⅱ. Contractor's perspective : The cost per meal in the year 2001 was composed of 1,905 won for food cost, 1,081 won for labor cost, 222 won for expenses, 114 won for VAT, 14 won for rent and 146 won for miscellaneous or controllable expense, representing 109 won loss per meal. The profit-and-loss contract cost is higher than the fee-contract cost. The ratios of food cost, labor cost and expenses are higher and the ratios of miscellaneous or controllable expense, VAT, rent and profit are lower in hospitals with more than 400 beds compared with those less than 400 beds. However, no significant differences are present between these two groups of hospitals. The actual contract period was 2.2 years upon initial contract and 1.2 years upon renewal. The initial investment cost was 53 million won and the cost of renovation and repair was 8.5 million won. Significant differences were present between two groups of hospitals. The conditions of employment and number of personnel hired by contractors for contract patient food services were significantly different according to the number of beds.

• Journal of Nutrition and Health
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• v.36 no.10
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• pp.1083-1093
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• 2003

Efficient financial management is a critical factor in achieving school foodservice goals. The objective of this study was to suggest efficient financial management practices in secondary school foodservices. In pursuit of this objective, we first identified performance indexes for measuring the success of financial management. Second, we suggested financial management standards, financial data classification methods and a report system. Last, we analyzed operating ratios with the financial data of self-operated and contract-managed school food services. The data were collected through an open-ended questionnaire from 10 middle/high school foodservices in Seoul and Kyeonggi Provincial during on-sites visits and interviews with dieticians and managers. Student participation, sales goals, re-contract frequency and number and cost of disaster loss were identified as the performance indexes for financial management. Income statements were compiled by identifying and classifying financial data. Total revenues consisted of subsidies, meal sales, other revenue and interest. Expenditures consisted of purchased food, salaries and wages, utility costs, office supplies, kitchen supplies, purchased services, company overhead indirect costs, facility investment and maintenance, facility usage expenses, employee benefits and miscellaneous. Mean price of a meal was 2,326 won at self-operated foodservices when the subsidies were included as revenues and 2,360 won at contract-managed foodservices. When including the subsidies as revenues, the operating ratios of self-operated foodservice showed that the food cost percentage was 66.9％, labor cost 23.2％, operation cost 9.9％ and profit 0％. The correspond figures at contract-managed foodservices were 57.6％, 21.5％, 15.3％, and 5.5％, respectively. Food costs in self-operated foodservices was significantly higher than that for contract-managed foodservices, however, facility investment and maintenance and facility usage expenses at self-operated foodservices was significantly lower than those for contract-managed foodservices. Based on this study, the methodology and classification system of financial data was found to be applicable to assess the financial structure of school foodservices.