As the number of enlistees decreases due to social changes like declining birth rates, it is necessary to conduct research on the appropriate recalculation of the force that considers the future defense sufficiency and sustainability of the Army. However, existing research has primarily focused on qualitative studies based on comprehensive evaluations and expert opinions, lacking consideration of sustained support activities. Due to these limitations, there is a high possibility of differing opinions depending on perspectives and changes over time. In this study, we propose a quantitative method to calculate the proper personnel by applying system dynamics. For this purpose, we consider a standing army that can ensure the sufficiency of defense between battles over time as an adequate force and use battle damage calculated by wargame simulation as input data. The output data is the number of troops required to support activities, taking into account maintenance time, complexity, and difficulty. This study is the first quantitative attempt to calculate the appropriate standing army to keep the defense sufficiency of the ROK Army in 2040, and it is expected to serve as a cornerstone for adding logical and rational diversity to the qualitative force calculation studies that have been conducted so far.
In contemporary global warfare, the significance and imperative of air transportation have been steadily growing. The Republic of Korea Air Force currently operates only light and medium-sized military cargo planes, but does not have a heavy one. The current air transportation capability is limited to meet various present and future air transport needs due to lack of performance such as payload, range, cruise speed and altitude. The problem of population cliffs and lack of airplane parking space must also be addressed. These problems can be solved through the introduction of heavy cargo planes. Until now, most studies on the need of heavy cargo plane and increasing air transport capability have focused on the necessity. Some of them suggested specific quantity and model but have not provided scientific evidence. In this study, the appropriate ratio of heavy cargo plane suitable for the Korea's national power was calculated using principal component analysis and cluster analysis. In addition, an optimization model was established to maximize air transport capability considering realistic constraints. Finally we analyze the results of optimization model and compare two alternatives for force structure.
In contemporary global warfare, the significance and imperative of air transportation have been steadily growing. Nevertheless, the Korean Air Force currently operates only with small and medium-sized military cargo planes, lacking larger aircraft. Consequently, the efficiency of their operations is constrained by the limited air transport capacity and the aging of their existing fleet, among other factors. Therefore, we have to consider to make future air transportation capability. Although the 2nd large-sized cargo-plane acquisition project is ongoing, its quantity is very small. In this study, we propose an optimal prediction model that takes into account practical constraints such as parking space availability, pilot availability, wartime daily maximum loads, while simultaneously maximizing both the effectiveness and efficiency of transport capacity for future warfare envirionment.
PURPOSES: The purpose of this study is to develop a methodology for estimating additional carbon emissions due to freeway incidents. METHODS : As our country grows, our highway policy has mainly neglected the environmental and social sectors. However, with the formation of a national green growth keynote and an increase in the number of people interested in environmental and social issues, problems related to social issues, such as traffic accidents and congestion, and environmental issues, such as the impact of air pollution caused by exhaust gases that are emitted from highway vehicles, are beginning to be discussed. Accordingly, studies have been conducted on a variety of environmental aspects in the field of road transport, and for the quantitative calculation of greenhouse gas emissions, using various methods. However, in order to observe the effects of carbon emissions, microscopic simulations must use many difficult variables such as cost, analysis time, and ease of analysis process. In this study, additional greenhouse gas emissions that occur because of highway traffic accidents were classified by type (incident handling time, number of lanes blocked, freeway level of service), and the annual additional emissions based on incidents were calculated. According to the results, congestion length and emissions tend to increase with an increase in incident clearance time, number of occupied lanes, and worsening level of service. Using this data, we analyzed accident data on the Gyeong-bu Expressway (Yang-Jae IC - Osan IC) for a year. RESULTS : Additional greenhouse gas emissions that occur because of highway traffic accidents were classified by type (incident handling time, number of lanes blocked, freeway level of service) and annual additional emissions caused by accidents were calculated. CONCLUSIONS: In this study, a methodology for estimating carbon emissions due to freeway incidents was developed that incorporates macroscopic flow models. The results of the study are organized in the form of a look-Up table that calculates carbon emissions rather easily.
PURPOSES : The Toll Collection System (TCS) operated by the Korea Expressway Corporation provides accurate traffic counts between tollgates within the expressway network under the closed-type toll collection system. However, although origin-destination (OD) matrices for a travel demand model can be constructed using these traffic counts, these matrices cannot be directly applied because it is technically difficult to determine appropriate passenger car equivalent (PCE) values for the vehicle types used in TCS. Therefore, this study was initiated to systematically determine the appropriate PCE values of TCS vehicle types for the travel demand model.
METHODS: To search for the appropriate PCE values of TCS vehicle types, a traffic demand model based on TCS-based OD matrices and the expressway network was developed. Using the traffic demand model and a genetic algorithm, the appropriate PCE values were optimized through an approach that minimizes errors between actual link counts and estimated link volumes.
RESULTS : As a result of the optimization, the optimal PCE values of TCS vehicle types 1 and 5 were determined to be 1 and 3.7, respectively. Those of TCS vehicle types 2 through 4 are found in the manual for the preliminary feasibility study.
CONCLUSIONS: Based on the given vehicle delay functions and network properties (i.e., speeds and capacities), the travel demand model with the optimized PCE values produced a MAPE value of 37.7%, RMSE value of 17124.14, and correlation coefficient of 0.9506. Conclusively, the optimized PCE values were revealed to produce estimates of expressway link volumes sufficiently close to actual link counts.
Recently, companies are trying to gain a competitive advantage in the market to meet the voice of customer. For this purpose, QFD has been used as product development technology in many areas to include the customer’ requirements. Also, Kano model has been used to understand the customer’ requirements for an effective way. Therefore integration of Kano model and QFD can more efficiently reflect the customer’ requirements when designing a new service. This paper proposes PI index by taking into account the current satisfaction position of our company and competitors while IR (Improvement Ratio) value was set uniformity. This study suggests a more accurate index to predict potential improvements and calculates the final importance or priority. Through case studies targeted at elevator maintenance companies, we can have a general idea how much to improve in the near future and estimate the final importance of customer requirements.
일반국도유지보수 의사결정지원시스템에는 DB 이외에 1)포장상태지표의 공용성 모형, 2)포장상태지표 기반의 차량주행속도모형, 3)경제성 분석 모형과 4)의사결정지원 모형으로 구성된다. 특히 국토교통부의 「교통시설 투자지침서」에서 제시하는 도로이용자 및 사회·환경비용은 모두 차량운행속도의 함수로 구성되어있기 때문에 신뢰성 있는 차량운행속도모형의 개발이 요구된다. 즉, 도로의 상태기반 주행속도모형은 도로 부문의 편익 비용 항목 중 1)통행시간비용, 2)차량운행비용, 3)대기오염 비용, 4)온실가스비용, 5)소음비용 항목 등 이용자 비용 산정에 활용된다.
본 연구에서는 포장상태가 차량주행속도의 변수로 포함되도록 모형화 하는 것이 핵심이다. 먼저 유지보수 전·후의 『포장상태-차량속도』자료를 확보하기 위해 NC-200을 통해 현장조사를 실시하였다. 순창, 제천, 단 양, 증평의 네 구간을 선정하여 각 구간의 지형 분석, 교통량 측정 및 특성 분석을 실시하였다. 필터링 된 속도 자료를 활용하여 유지보수 전·후의 속도 차이를 AD(Anderson-Darling) 검정, t 검정, Mann-Whitney U 검정을 통해 통계적 유의성을 검정하였다. 모형개발을 위해 통계적 유의성이 검증된 구간 및 아스팔트 포장구간의 속도자료를 활용하여 표 1과 같이 모형을 개발하였다.
연구결과, 승용차를 대상으로 제한속도가 60km/h, 80km/h인 경우의 평지를 대상으로 한 모형구축 과정을 통해 세 가지 도로 상태(균열, 소성변형, IRI)별 속도는 통계적으로 유의한 차이가 있음을 확인하였다. 개발된 속도모형을 통해 도로 이용자비용의 산출이 가능하며 향후 일반국도유지보수 의사결정지원시스템의 경제성 분석 및 유지보수 대상구간의 우선순위 결정 등 다양하게 활용가능하리라 기대된다.
I suggest a new method to determine the importance values of quality attributes which use the satisfaction index and dissatisfaction index of customer in Kano's model. A case study of TV set are solved by the proposed method and the result is compared with AHP pairwise comparisons and ASC(Average Satisfaction Coefficient). The results of the proposed method is similar with those of AHP pairwise comparisons and ASC. The proposed method is an effective tool to determine the importance values of quality attributes to supplement existing research's shortcomings.
본 연구의 목적은 차종별 교통류 모형을 이용한 편도 2차로 고속도로 공사구간의 용량 값을 산정하는 것이다. 공사구간의 교통류 모형은 공사구간의 유입부 및 유출부를 대상으로 차종별 모형과 승용차 환산계수를 적용한 전체 차량에 대한 모형으로 도출하였다. 차종별 모형에서 산정된 최대교통류율은 승용차환산계수 및 중차량 비율을 적용하여 공사구간의 용량 값으로 전환하였다. 차종별 모형의 유입부 및 유출부 최대교통류율 값은 각각 1,845pcphpl과 1,884pcphpl로 산정되었으며 차량 전체를 대상으로 한 모형의 최대교통류율은 차종별 결과보다 높게 분석되었다. 모형의 비교 검증을 위하여 최대밀도에 따른 거리 차두간격을 적용하였다. 공사구간의 용량은 공사구간의 흐름이 안정된 유출부 용량보다 공사구간 진입을 위한 차선 변경 등으로 교통흐름이 원활하지 못한 유입부 용량에 좌우되므로 유입부 교통류 모형의 최대교통류율 값인 1,800pcphpl을 편도 2차로 고속도로 공사구간 용량 값으로 산정하였다.
도로기하설계의 기준이 되는 요소에는 시거(視距), 차량의 안정성, 운전자의 안락감, 배수, 경관 등이 있으며, 이 중 선형 결정에 있어서 가장 결정적인 요소는 시거이다. 도로와 그 위를 주행하는 운전자의 관찰 행위는 분명히 입체적인 특성을 가지고 있다. 그러나, 현행의 도로설계는 과정상 여러 가지 제약조건으로 인해 평면과 종단을 분리하여 2차원적으로 시거를 분석하여 설계시 적용하여 왔다. 입체시거의 계산이 까다롭고 2차원적인 시거가 실제의 입체시거와 크게 차이가 나지 않는 것도 그 원인에 포함된다. 하지만 최근의 도로안전에 관한 연구에서 도로일관성이 대두되었고, 이러한 일관성 평가를 위해서는 안전요소들의 안전여유(safety of margin)를 계산할 수 있어야 한다. 따라서 시거에 관한 정확한 안전여유를 계산하기 위해서는 정확한 입체시거의 적용이 필요하다고 할 수 있다. 본 연구는 임의의 평면선형과 종단선형의 합성으로 이루어진 도로선형에서 입체시 거를 계산할 수 있는 모형을 유도하는데 초점을 두었다. 제시되는 모델을 이용하여 도로선형을 가정한 후 시거분석을 실시해 보았으며 2차원적 시거와의 단순비교를 통하여 두 경우의 시거에 차이가 있음을 확인하였다. 제안된 모델은 3차원 도로선형에 대한 설계기준을 정량화 하거나 입체시거 분석이 요구되는 도로안전의 연구에 기여할 수 있을 것으로 기대된다.
인터넷 쇼핑몰이 활성화되면서 소비자들은 이전보다 많은 상품 선택 기회를 갖게 되었다. 이러한 변화는 소비자의 권익 보호 차원에서 일면 긍정적이지만, 상품 구매를 위해 소비자가 한꺼번에 많은 대안들의 평가를 해야 한다는 점에서는 부정적이라고 할 수 있다. 특히 인터넷 쇼핑몰은 거래가 대면하지 않고 일어난다는 속성을 가지고 있어, 고객의 상품구매 과정을 지원해 줄 기능 마련이 시급하다. 본 연구에서는 이러한 문제의 효과적인 해결을 위해, 다기준 의사결정기법(Multicriteria decision making) 중 하나인 PROMETHEEⅡ(Preference Ranking Organization METHod Enrichment Evaluation)를 사용하여 구매고객의 구매기준에 따른 상품들의 순위를 제공하는 웹 어플리케이션을 제시하고자 한다.