호텔 고정비를 고려한 변동비 영업전략에 관한 연구

김혁수 ( Hyuk Soo Kim ) 한국호텔리조트학회(구 한국호텔리조트카지노산학학회) 2015 호텔리조트연구 Vol.14 No.1

The purpose of this study is to suggest new operating strategy of room sales promotion using variable costing with hotel fixed cost. I used variable costing of example hotel``s room department income statement and made new income statement 3 case. First is variable costing room department income statement. Second is variable costing room department income statement in the condition of additional room 10% sales up sensitive case 1, pessimistic point . Third is variable costing room department income statement in the condition of additional room 10% sales up sensitive case 2, optimistic point. The results are as follows; Operating profit rate of variable costing is 95%, operating profit rate of variable costing in the condition of 10% sales up sensitive case 1, pessimistic point is 96%, operating profit rate of variable costing in the condition of 10% sales up sensitive case 2, optimistic point is 99%. Using very low variable cost, very high contribution operating profit (95%, 96%, 99%), I suggest new operating strategy of room sales promotion.

호텔 직접원가계산에 의한 객실판촉의 탐색적 연구

김혁수(Hyuk Soo Kim) 한국관광연구학회 2015 관광연구저널 Vol.29 No.2

The purpose of this study is to suggest new operating strategy of room sales promotion using direct (variable) costing with hotel variable costs. I studied detailedly empirical study of room`s direct cost(variable cost) based on price discount strategy in the room sales promotion`s main factor. As the arithmetic expression, room sale - variable cost = contribution margin(profit), if low variable cost makes a sharp cut (discount) in room price. So, in this paper I investigate empirical study of hotel`s very low variable cost compared with general industries. This study will contribute to the hotel industries in the reason first detail analysis of making profit in spite of sharp cut(discount) room price. I used entire costing of example real hotel``s room department income statement at table 1 and made new income statement by direct variable costing at table 2, made new linear function y = a + bx ; y = 295,567,711+ 0.102121635 x) at table 3. The results are as follows; variable cost rate is 11.0% by table 2 used accounts analysis method, 10.2% by table 3 used least squares method. Operating profit rate of direct variable costing by table 2 is 89.0%, operating profit rate of direct variable costing in the condition of used least square method by table 3 is 89.8%. So, using very low variable cost(11.0 or 10.2%), very high contribution operating profit rate (89.0% or 89.8%), 99%), I suggest renovative new operating strategy of room sales promotion in Korean hotel industry.

Calculating Wind Variability Costs with Considering Ramping Costs of Conventional Power Plants

Xuemei Dai,Kaifeng Zhang,Jian Geng,Ying Wang,Kun Yuan 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.3

Due to the variability of the wind power, conventional power plants are required to ramp more frequently to mitigate the imbalance of generation and supply, which increase the total cost of power systems. The increase of the cost is termed the “variability cost” of wind power. Generally, it includes the additional ramping cost, reserve cost and fuel cost of conventional plants. In this paper, we propose an alternative scenario construction method to calculate the “variability cost” of wind power from the viewpoint of the power system schedule. Firstly, in the alternative scenario, a new energy proxy with zero wind variability costs is constructed. Then, a unit commitment optimization model considering ramping costs is developed. The operation costs of power systems under two scenarios (alternative one and real one) are calculated and the diff erence between two costs is the variability cost. Furthermore, we apply the proposed method to calculate the variability costs of the wind farm cluster. The simulations show that the variability cost increases with higher penetration and higher variability of wind power. Meanwhile, it is found that the variability cost of the wind farm cluster as a whole is lower than the sum of variability costs of each wind farm.

원가기반 제한경쟁과 비용왜곡 요인 : 변동비 반영 전력시장에서의 실제변동비 반영사례를 중심으로

김명석 ( Myung Seok Kim ),조성봉 ( Sung Bong Cho ) 한국환경경제학회·한국자원경제학회(구 한국환경경제학회) 2014 자원·환경경제연구 Vol.23 No.3

비용을 보상하는 원가규제 방식으로 알려진 투자보수율 규제 또는 총괄원가주의 규제의 경우 피규제자는 비용을 부풀리려는 유인을 갖게 마련이다. 그런데 생산공장별 원가를 규제자가 파악하고 이들 간의 경쟁을 유도하는 경우에는 단기적으로 ‘수인의 딜레마’ 상황이 나타나 원가 과대보고와는 방향이 다른 원가 과소보고 방향으로의 비용왜곡 요인이 발생할 수 있다. 변동비 반영 전력시장의 경우 발전기의 운전시간이 늘어날수록 실제변동비와 등록변동비 간의 차이는 점점 커지게 되지만 복합화력 발전사들은 가동률과 발전량을 높게 유지하기 위해 등록변동비를 유지시키려는 전략적 선택을 할 수 있다. 그 결과 궁극적으로 수익성이 악화되고 신규설비에 대한 투자를 유도하지 못하며 설비예비율은 적정 이하로 떨어지는 ‘수인의 딜레마’ 상황이 나타날 수 있다. 이에 따라 발전사들의 자기변동비가 실제 효율과 유사하도록 관련 규정을 개정할 필요가 있다. Rate-of-return regulation where a regulator compensates the utilities based upon the cost incurred the regulated companies have the incentive to over-report cost level. However, in case of cost-based competition where a regulator knows the cost of each plant involved and induce the competition among them, one can encounter prisoner`s dilemma situation in the short run where the regulated firms under-report cost level. For instance, in case of cost-based pool, a generator may have a strategic behavior to keep its registered variable cost higher than the actual level to maintain its operation rate and generation amounts higher. Eventually, however, such behavior decrease the profitability of a generator and discourage new entry jeopardizing required level of capacity reserves. This is a typical Prisoner`s Dilemma situation. The power market operating rule should be revised so that generators` registered variable cost reflect actual level of variable cost.

Development of a control algorithm aiming at cost-effective operation of a VRF heating system

Moon, Jin Woo,Yang, Young Kwon,Choi, Eun Ji,Choi, Young Jae,Lee, Kwang-Ho,Kim, Yong-Shik,Park, Bo Rang Elsevier 2019 Applied thermal engineering Vol.149 No.-

<P><B>Abstract</B></P> <P>This study aims to develop a control algorithm that can operate an intermittently working variable refrigerant flow (VRF) heating system in a cost-effective manner. An artificial neural network (ANN) model, which is designed to predict the heating energy cost during the next control cycle, is embedded in the control algorithm. By comparing the predicted energy costs for the different setpoint combinations for the system parameters, such as the air handling unit (AHU) supply air temperature, condensing warm fluid temperature, condensing warm fluid amount, and refrigerant condensing temperature, the control algorithm can determine the most cost-effective setpoints to optimally operate the heating system. Two major processes are conducted—development of the predictive control algorithm in which the ANN model is embedded, and performance tests in terms of prediction accuracy and cost efficiency using computer simulation. Results analysis reveals that the ANN model accurately predicts the energy cost, presenting a low coefficient of variation of the root mean square error value (7.42%) between the simulated and predicted results. In addition, the predictive control algorithm significantly saves on the heating energy cost by as much as 7.93% compared with the conventional heuristic control method. From the results analysis, the ANN model and the control algorithm show the potential for prediction accuracy and cost-effectiveness of the intermittently working VRF heating system.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cost-effective algorithm was developed for the control of VRF heating system. </LI> <LI> ANN model was embedded in the algorithm to determine the cost-effective operation. </LI> <LI> ANN stably predicted the cost for space heating. </LI> <LI> Proposed algorithm saved the heating cost compared to the conventional method. </LI> </UL> </P>

공급자 관점의 정보시스템 유지보수 비용항목과 조정계수 산정방안

이병철 ( Byoung Chol Lee ),류성열 ( Sung Yul Rhew ) 한국정보처리학회 2013 정보처리학회논문지. 소프트웨어 및 데이터 공학 Vol.2 No.11

지금까지의 정보시스템 유지보수비 산정은 발주자 중심으로 이루어져 업무량에 비해 적은 비용으로 인한 공급자의 원가부담 문제점을 해결 하지 못하고 있다. 본 연구는 공급자 중심에서 정보시스템 유지보수 비용을 산정하기 위한 기반연구로서 유지보수의 비용 항목을 도출하고 발 주자와 공급자의 유지보수 비용의 격차를 조정하기 위한 조정계수를 제안한다. 유지보수의 비용항목을 도출하기 위하여 기존의 유지보수 활동에 대한 비용요인 기반연구에 유지보수 공급자의 활동들 추가하여 고정비와 변동비로 구분하고 분류한다. 발주자와 공급자의 유지보수 비용의 격차를 조정하기 위하여, 발주자 중심의 유지보수 비용 산정 시 포함되지 않 은 자동화 도구에 의해 생성된 코드, 유틸리티, 컴포넌트 등과 같은 조정요인들을 찾아내고 K기업의 3년간 유지보수 수행 데이터를 검토 분석 하여 조정계수 요인에 대한 격차가 K기업의 경우 13%정도가 됨을 확인하였다. The estimation of maintenance cost of information system so far has been conducted centered on the ordering body, so the problem of provider`s having to cover the cost due to small cost compared to the amount of work is not solved. This study is a base study for estimating the maintenance cost of information system centered on provider, and it deduces cost items of maintenance and suggests adjustment factors for adjusting the gap between the ordering body and provider regarding the maintenance cost. In order to deduce the cost items of maintenance, this study adds the activities of the provider for maintenance to the base study of cost factors regarding the existing maintenance activity, divides, and classifies them into the fixed cost and variable cost. In order to adjust the gap between the ordering body and provider regarding the maintenance cost, this study found the adjustment factors such as the code, utility, and components created by the automatic tool that was not included when estimating the maintenance cost centered on the ordering body. After examining and analyzing K Company`s data of maintenance performance for three years, it confirmed that the gap regarding the adjustment factors was about 13% in case of K Company.

연료비 이외의 항목도 발전시장의 변동비로 간주할 수 있는가?

조성봉 ( Sung Bong Cho ) 한국환경경제학회·한국자원경제학회(구 한국환경경제학회) 2011 자원·환경경제연구 Vol.20 No.3

2005년 5개 발전사업자는 변동비 반영시장에 기존의 연료비 외에 연료사용 전후에 관련된 부대비용도 포함시킬 것을 건의하였다. 발전량과의 OLS 분석을 통해 관련을 검토한 결과 이 같은 변동비 희망항목이 발전량과 통계적으로 유의한 관계를 갖고 있다는 일반적인 성향을 발견할 수 없어서 변동비로 인정할만한 종합적인 근거는 취약하였다. 변동비 희망항목 중 몇몇 항목이 특정 발전설비에 대해 OLS 분석에서 통계적 유의성을 갖는 등 변동비가 될 수 있는 가능성을 보이고 있다. 그러나 비용산정의 시차, 재고관리와 이에 따른 회계처리 방법 등의 문제로 인하여 발전량과 유의적인 통계적 관계를 보이지 못할 수 있다. 따라서 변동비 희망항목에 대해서는 통일된 기준을 세우고 자료를 표준화하는 작업이 선행되어야 할 것으로 판단된다. In 2005, five Korean generation companies suggested to include non-fuel ancillary costs incurring in the process of managing fuels and ashes as variable costs in Korean Cost-Based Pool. OLS analysis seeking statistical relation with the amount of generation did not provide sufficient ground for such argument. However, some cost items in this category showed meaningful statistical relation for certain generation facilities hinting some possibilities for the candidate of variable costs in the future. Time lag related to cost evaluation, problems related to inventory control and accounting method related to this may block the statistical relationship with the amount of generation. Unified criteria and standardization of the data are necessary before we proceed further to consider them as variable costs.

민간투자사업의 원가구조 분석 연구

서한결,황희주 한국회계정책학회 2022 회계와 정책연구 Vol.27 No.1

[연구목적] 본 연구는 사회기반시설에 대한 민간투자사업의 유형별 원가구조를 추정 분석하는 것을 목적으로 한다. 사업유형은 시설별로 도로사업, 항만사업, 철도사업, 환경사업으로 구분하고, 원가구조 분석은 총원가에서 변동원가와 고정원가가 차지하는 비율을 추정하는 것으로한다. [연구방법] 본 연구는 전자공시시스템(Dart system)에 공시된 감사보고서를 참고로 2008년에서 2019년까지의 409개 민간투자 사업-연도 표본을 활용하였다. 다중 회귀분석을 통해 원가함수를 도출하고 계정분류법을 활용하여 변동원가 및 고정원가 비율을 추정하였다. [연구결과] 도로 사업의 고정원가 비율 88.70% (변동원가 11.30%), 철도사업의 고정원가 비율 64.27% (변동원가 35.73%), 항만 사업 63.76% (변동원가 36.24%), 환경사업 40.58% (변동원가 59.42%)가 도출되었으며, 추가 분석을 통해 이와 유사한 비율로 도출되었음을 확인하였다. [정책적 시사점] 본 연구 결과는 민간투자사업의 주무관청과 사업신청자의 약정 사업수익률협상 과정에서 주요한 기초자료로 활용될 수 있으며, 나아가 공공부문 사업 투자 의사결정에서원가구조 특성이 반영되어야 함을 시사한다. [Purpose] The purpose of this study is to estimate and analyze the cost structure according to business type of PPP project. The project types were classified into road, port, railroad, and environmental projects, and the cost structure analysis estimates the ratio of variable costs or fixed costs to total cost. [Methodology] For this analysis, 409 business-year samples were used from 2008 to 2019, referring to the audit report published in the Dart System for SPC of 53 PPP projects. The cost function was derived through multiple linear regression analysis, and the variable cost and fixed cost ratio were estimated using the account classification method. [Findings] As a result of the analysis, the fixed cost ratio for road, railroad, port, and environmental projects was estimated to be 88.70%, 64.27%, 63.76%, and 40.58%, respectively, and it was confirmed that the results were similar through additional analysis. [Policy Implications] The results of this study suggest that as basic data for policy decision-making, it can be used in the process of determining the return of rate of PPP projects, and provide the implication that cost structure characteristics should be considered in public sector investment decisions.

A STUDY ON OPTIMIZED SIZE OF A MOBILE HARBOR FOR SOUTH KOREA COASTAL SERVICE

허성국,박남규 한국항해항만학회 2011 한국항해항만학회지 Vol.35 No.2

The aim of paper is to calculate the optimized size of Mobile Harbor(MH) which would be operated in South Korea coast area. MH is the combined entity which has the function of both ship and container port. In estimating the optimized size, the total cost concept is applied to the different size of MH. Trade-off factors for calculating total cost are MH cost and the over-capacity lost cost. The factors for MH cost estimation are the cargo demand, distance from origin to destination, voyage route and MH's fixed and variable cost in both sailing and port. The other cost is the over-capacity lost cost which is occurred from dead space in case of oversize compared with a voyage demand. The alternatives for the least cost are 250TEU, 500TEU, 750TEU and 1,000TEU sized vessel. The result of research is that 250TEU sized vessel is optimized in a South Korea costal service. If the coastal area be separated in terms of voyage distance or the specific area in considering trade, the optimized size is changed depending upon distance.

Stability of Construction Cost-variability Factor Rankings from Professionals' Perspective: Evidence from Dar es Salaam -Tanzania

Shabani, Neema,Mselle, Justine,Sanga, Samwel Alananga,Kanuti, Arbogasti Isidori Korea Institute of Construction Engineering and Ma 2018 Journal of construction engineering and project ma Vol.8 No.2

This study investigates the stability of professionals' cost variability factor-rankings across different levels of cost-variability and response scenarios. Descriptive statistics are used to examine the stability of factor-ranking for 20 cost variability factors and a Multinomial Logistic (MNL) regression model was implemented to examine the stability of cost variability factors across three cost variability levels. The finding on the descriptive statistics indicated that professionals' factors-rankings are stable only for external factors. The MNL regression results on factor-stability suggested that 8 out of the 20 evaluated factors were unstable determinant of lower cost variability levels. These factors are "risk associated with the project", "personal bias and poor professionalism of the estimators", "limited time available to complete the project", "lack of skills and experience by estimator" "geographical location of projects", "incomplete & rush designs for estimate", "unforeseen or unexpected site constraints", "high class bidders for the contractors". Similarly lack of experience and large size projects were observed to be unstable as well. These observations suggest that professionals' view on pre-tender cost variability factor-ranking yields unstable factor rankings hence should not be relied upon as the only mechanisms to mitigate cost related risks in construction projects.