• Information and Communications Magazine
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• v.29 no.7
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• pp.89-96
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• 2012

정보통신공사의 공사비 산정은 그동안 원가계산 방식으로 이루어져 왔으나, 최근 들어 건설 및 전기분야에서와 같이 실적공사비를 활용할 수 있도록 제도 시행을 추진하고 있다. 그러나 실적공사비를 적용하기 위해서는 과거 공사비 실적자료를 현가화 할 수 있는 지수의 개발이 전제되어야 함에도, 그동안 정보통신공사는 한국건설기술연구원의 통신공사비지수(기타 특수건설의 최하위지수)나 한국은행의 생산지물가지수를 이용할 수밖에 없는 한계를 지니고 있었다. 이에 본 연구에서는 실적적산 데이터를 기반으로 정보통신공사의 특성을 고려한 정보통신공사비지수를 제시하고자 한다. 개발된 지수는 실적공사비 자료의 현가화 뿐 아니라, 물가변동에 따른 계약단가 조정(Escalation), 정보통신분야의 거시적인 동향을 파악할 수 있는 주요 지표로 정보통신공사의 사업비산정 및 관련 분야의 기초자료로 활용될 수 있다.

• Korean Journal of Construction Engineering and Management
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• v.5 no.6 s.22
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• pp.203-211
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• 2004

This study is the results to survey on the problems and improvable Policies for current escalation system in construction contracts, through a Delphi survey to experts. From the survey results, it is desirable to decide the fluctuation rate of construction cost, which is the requirement of escalation clause, on the basis of inflation rate or construction cost index. The desirable price fluctuation rate is proposed as a $3\%$ level. However, it is difficult for construction companies to cope with the sudden increase of material price in advance, arising from short-term shock factors such as exchange rate and international raw material's price. Accordingly escalation system for specified materials, as an exceptional mode, should be introduced. As a method to calculate the fluctuation rate, ARCA(adjustment rate for the categories of articles) is more desirable than ARI(adjustment rate for an index), because the ARCA can be more reflected the characteristics of each construction work.To rationalize the ARI method, it is needed to announce the wage index, material index and machinery expense index via detailed classification by construction types. Also, it is desirable to prescribe the bidding date as a starting date of the price change, rather than contact signing date. considering the price change can happen since the biddiilg stage.

• The Korean Journal of Applied Statistics
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• v.29 no.1
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• pp.205-220
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• 2016

Seasonal adjustment is useful to provide a better understanding of underlying trends in Korean economic statistics. The seasonal component also includes calendar effects such as Seol and Chuseok. Most popular seasonal adjustment methods are X-12-ARIMA of the U.S. Bureau of the Census and TRAMO-SEATS of the Bank of Spain. Statistics Korea and the Bank of Korea compile seasonally adjusted series of several Korean economic statistics. This paper illustrates basic principles for seasonal adjustment and the current status of seasonal adjustment in Korea based on previous research. In addition, several issues on seasonal adjustment are addressed.

• Korean Journal of Construction Engineering and Management
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• v.20 no.3
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• pp.3-11
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• 2019

The construction of a facility is an act whereby infrastructure such as roads and railways and other facilities such as housing and office spaces are constructed, and due to the characteristics of the relevant industry where such construction is carried out in a custom order method, it requires a long period of time mostly. While the construction is carried out over a long period of time, fluctuations in the price of raw materials required for the construction occur. Therefore, the cost of the construction also fluctuates inevitably. The fluctuation of the construction cost meshes closely with the profit of a constructor and the efficiency of government spending. Therefore, it is necessary to maintain the construction cost at a reasonable level by adjusting the construction cost rationally in order to secure the required construction quality and spend the budget efficiently. The buffer system for solving such problem is the contract amount adjustment system by fluctuations in prices (Escalation/De-Escalation). In this study, the method combining the escalation method based on the item adjustment method was suggested for an efficient contract amount adjustment method. In addition, it is proposed that there be an investigation and codification of matters not applied to government acts and regulations on contracts related to the adjustment of fluctuations in prices legally.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.423-426
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• 2002

The foundation for developing a cost estimation system based on historical data has been being prepared in Korea. Historical data is a priori of developing a cost estimation model. Cost Index, one of the historical data, is used to estimate construction cost and to adjust the amount of contract money in the foreign country, whereas it is not used in domestic except for the road construction project in Korea. Construction cost indices can be used by an estimator in tender analysis, pricing, price adjustment, cost planning, and forecasting. In this regards, this paper identified the problems in developing Cost Index evaluation process by comparing the standard of framing Cost Index used in British to the one used in Korea. Then, the scheme for improving a Cost Index required for Site Developing Construction was proposed. Twenty-two cases of engineering estimate data were used to compare the domestic standard to the foreign one in deriving a Cost Index.

• Journal of the Korea Institute of Building Construction
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• v.12 no.1
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• pp.108-114
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• 2012

Escalation method examining the changes in price index has been widely utilized in public construction projects. The previous escalation method determined estimated changes in price based on the average unit price of contract items over a period of time. In relation to this method, the issue has been raised that the fluctuation rates of previous method show different trends compared with other related price indices, as the influence of the small group of contract items with large unit prices overwhelms the others. This research suggested an improved escalation method which estimates the fluctuation rate by examining the changes in CCI (construction cost index) and applies it to the total amount or the partial amount deducted for labor cost in price escalation for previous bid price method. To verify the improvement, a case study is conducted on an educational facility, and the fluctuation rate was estimated in two different base periods (short term, long term). The results over the long term showed similar tendencies to those of related price indices, as well as significant differences in fluctuation rates compared to those of the previous method.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.435-439
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• 2006

The purposes of study is to propose a new method contract price adjustment in construction projects. The research method of this study includes a case analysis and questionnaire survey. The results of this study are as follows: 1) For improvement method of contract amount adjustment, enactment for legislation pertaining to computation methods such as military's organization through total unit cost, and price flexibility computation at the point of design modification were presented. 2) Arithmetic formulas for cases in which volume is deleted or modified below the price flexibility exemption amount or in which there is no change to quantity, at the occurrence of design modification resulting from price flexibility, were proposed.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.123-130
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• 2003

The Environmental Impact Quotient(EIQ) has been used to organize the extensive toxicological and soil residue data available on some fruit vegetables pesticides into a usable form for field use. It addresses a majority of the environmental concerns that are encountered in agricultural systems including farm worker, consumer, ecological and environmental safety. The EIQ made use of the rating system by using the EIQ equation. The EIQ of pesticides registered for oriental melon was higher than that of other in terms of farm worker, consumer and environmental safety. Pesticides registered for red pepper showed highest EIQ in ecosystem. The EIQ decreased in order of insecticide> fungicide> herbicide> plant growth regulator. The environment Impact Quotient for the pesticides registered in fruit and vegetables decrease gradually.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.9
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• pp.2027-2034
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• 1997

Frame relay is a fast packet switching technology that performs relaying and multiplexing frames with variable lengths over a wide area link at the T1 or E1 speed, by elminating error and flow control in the network. In frame relay networks, congestion control is typically performed through the rate enforcement with a discard eligibility (DE) bit, and the explicit negative feedback meachanisms using explicit congetion notification bits. In this paper, we consider the congestiong control scheme using the rate enforcement mechanism with DE bit for frame relay network. Assuming that each frame with exponentially distributed length arrives according to the Poission fashion, we can treat the frame relay switch as an M/M/1/K priority queueing system with pushout basis. We analyze and present the blocking probabilities and waiting time distributions of frames.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.11
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• pp.1142-1155
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• 2014

The classical PCM/PSK/PM scheme has been commonly used for TC & R applications between satellites and ground stations in the S-band. We analyzed TC & R link performance between ground station and the geostationary satellite which employs PCM/PSK/PM, when the satellite are particularly on the Super Synchronous Transfer Orbit(SSTO). The satellite parameters on SSTO are assumed to be those operating on the geostationary orbit, considering heritage aspect. In the uplink, the results shown indicate that sufficient margins over 3 dB are obtained when the EIRP of ground station is greater than 65 dBW. The down link performance is of great interest. By adjusting the telemetry modulation index and ranging modulation index, we could obtain the required margin of 3.0 dB in the down link, and find out the minimum G/T of ground station. In conclusion, the previously operated ground stations during LEOP at COMS launch, can be operational when GEO injection is made using SSTO(65,000 km and 70,000 km).