무선랜 설비투자의 경제적 타당성분석

안재경 ( Jae Kyoung Ahn ),홍정식 ( Jung Sik Hong ) 대한설비관리학회 2005 대한설비관리학회지 Vol.10 No.3

GIS(지리정보시스템)를 이용한 서울시 지하역사의 라돈농도 평가

안재경(Jae-Kyoung Ahn),최연순(Youn-Soon Choi),백남원(Nam-Won Paik) 한국실내환경학회 2006 한국실내환경학회지 Vol.2 No.2

The objective of this study was to identify the primary source of radon in Seoul subway stations, and to investigate a relationship between geology and radon. Especially, we expected that the granite areas would have substantially high levels of radon in subway stations. The indoor radon concentrations in subway stations were lognormally distributed. The geometric mean and geometric standard deviation of indoor radon concentration were 48.11 Bq/㎥ and 2.15, respectively. Indoor radon concentrations of eight measuring sites exceeded U.S. EPA criteria (148 Bq/㎥). The geological structure of the subway station regions under this study is characterized by biotite granite, alluvium, banded biotite gneiss and diluvium. Results indicate that bedrock geology can account for a significant portion of the indoor radon in subway stations. Indoor radon concentrations of one subway station were higher than those of other stations. The bed rock in this particular subway station was that of alluvium. We assumed that the unusual increase in measured radon concentration should be related mainly to the existence of the near inferred fault zone (p<0.0001). We selected ten subway stations with homogeneous bedrock type in order to compare radon concentrations of each basement level. There was a significant difference in radon concentration, depending on the basement levels in subway stations (p<0.05).

고속이동체 무선인터넷 인프라 진화방안 분석

안재경 ( Jae Kyoung Ahn ),송미자 ( Mi Ja Song ) 대한설비관리학회 2009 대한설비관리학회지 Vol.14 No.3

The objective of the research was to conduct economic analyses on the mobile satellite internet service in high speed moving object. From April of 2008, Korean Train Express over the speed of 300Km/hour has provided the paid wireless internet service to their passengers; however, the current service has shown limitations such as frequent disconnection, delay, or video play back freeze in tunnels. A survey was conducted to investigate the characteristics of korea express passengers in their service usage. Based on the survey, a system that integrates the satellite service into the existing wireless internet service was suggested, and its economic analyses were performed to confirm the economic feasibility on the development of the system. The economic analyses were performed with internet usage rate scenarios(8%, 6%, 2%) and fee scenarios (1,000 won, 1,500won, 2,000 won). Among the three scenarios, 6% with 1,500won gains economic justification as 8.3 billion Won of net present value and 15.5% of internal rate of return.

Data envelopment analyses on evaluating efficiencies of satellite communication and broadcasting R&D outcomes in Korea

안재경,안도섭,구본준,Ahn, Jae-Kyoung,Ahn, Do-Seob,Ku, Bon-Jun Korea Society of Satellite Technology 2008 한국위성정보통신학회논문지 Vol.3 No.2

Traditionally R&D evaluation has been performed by experts who can understand the contents of the study area very well. Recently extensive application of quantitative evaluation methods have been attempted for introducing the administrative management system that poses greater importance on records and results. More objective reviews on the R&D outcomes are called for gaining public supports. In this paper a bibliometrical analysis is to be performed to evaluate satellite communication and broadcasting public R&D outcomes for last 7 years. Data envelopment analysis method is selected for evaluating the efficiencies of multiple outputs (papers, patents, royalties, technology transfers) where multiple inputs (number of researchers and R&D expenses) are given. R&D outcomes from 22 research institutes are being compared and satellite communication and broadcasting R&D efforts turn out to be highly efficient.

An Integrated Production Management Model for a Manufacturing System

안재경,Ahn, Jae-Kyoung Korean Institute of Industrial Engineers 2003 산업공학 Vol.16 No.1

Business integration has been considered as one of the most critical success factors that enable the firms to gain competitive edges. Despite this trend, it has also been found among not a few companies that the activities that should be functionally tied with are performed even independently. In this study, an integrated model of production planning and inventory has been developed. Computerization of the production planning activities is proposed and implemented. We also proposed the reasonable inventory levels of each item using historic data of the items, which are composed of safety stock from the given fill-rate, operating stock from the production patterns, and reserved stock from the production planning. This study has helped the firm to have clearer job definition of the related processes, to tightly control the inventory by setting and tracing the reasonable fill rates for every product, and to quickly respond to the market changes through the computerized production planning process.

고속철도에서의 위성 광대역 인터넷서비스 경제성 분석

안재경,송미자,Ahn, Jae-Kyoung,Song, Mi-Ja 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.11B

인터넷을 기반으로 하는 IT 눈부신 발전과 더불어 언제, 어디서나, 시간과 장소에 구애받지 않고 인터넷을 사용할 수 있도록 하는 사회적 요구가 구체화 되고 있다. 이러한 요구에 부응하고자 국내에서는 시속 200km이상의 빠른 속도로 이동 중에 있더라도 초고속인터넷이나 방송 서비스를 제공할 수 있는 위성광대역 인터넷 시스템기술을 개발하고 있다. 본 연구에서는 위와 같이 개발된 시스템을 국내 고속철도(KTX)에 적용하여 서비스를 제공할 때, 관련 시설투자에 대한 경제적 타당성을 검토하고i라 한다. 경제성 분석을 위해 현재 유럽에서 이미 제공되고 있는 고속철도 인터넷서비스를 조사하였고, 국내 고속철의 특성을 감안하여 필요시설과 장비를 구성하여 항목별 비용분석을 수행하였다. 해외 사례와 비행기 등의 다른 운송수단에서 예상하고 있는 수요 및 요금 수준에 근거하여 고속철도 인터넷서비스 매출을 시나리오별로 전망하였으며, 각 시나리오에서 계산된 비용과 매출로부터 순현재가와 수익률을 산정 하였다. 본 연구의 결과는 관련 기술 개발에 대한 경제적 타당성 여부를 판단하는데 활용될 수 있으며, 비용효과적인 서비스 설계 및 구현에 도움을 줄 수 있을 것으로 기대된다. There is a growing demand to access the broadband internet while on the very fast move. In order to meet these users needs, much research has been made for providing the broadband internet and HDTV services via satellite broadband internet systems even at top train speeds above 200km/h. In this paper, economic analyses on the satellite broadband internet services for KTX are to be reviewed. Broadband internet to trains in Europe are investigated, and Boeing cases for planes are also examined. In the first step, system configuration which is composed of a hub, terminals, satellite, and gap fillers for the tunnel areas has been proposed. A terminal includes a ultra-fast high gain antenna installed on the roof of the train, and APs inside the coaches. Secondly, cost estimation on the capital expenditures as well as operating expenditures has been performed in the proposed configuration. From the european and Boeing cases, demand and tariff are postulated, consequently, service revenues are derived on the scenario basis. Thirdly, estimated costs and derived revenues make up net present value and internal rate of return in each scenario. Finally, conclusions and contribution of this study are presented.

연구논문 : 국방 품질시스템의 개선에 관한 연구

김만성,안재경 ( Man Sung Kim,Jae Kyoung Ahn ) 한국품질경영학회 1996 품질경영학회지 Vol.24 No.1

소프트웨어 자산관리를 위한 패키지소프트웨어 점검서비스 구현

차태원,안재경,Cha, Tea-Won,Ahn, Jae-Kyoung 한국정보처리학회 2009 정보처리학회논문지D Vol.16 No.1

국제적인 규제와 정부차원의 지원과 관리가 이뤄지고 있음에도 불구하고 일반기업 등에서는 여전히 소프트웨어자산에 대한 인식과 관리 소홀의 문제점을 안고 있다. 이는 관리해야 할 소프트웨어자산의 범위가 모호할 뿐 아니라 소프트웨어의 특성상 복사 및 설치가 쉽고 눈에 보이지 않아 관리 자체가 어렵기 때문이다. 즉 기업의 소프트웨어관리자는 구매부터 조달, 배포, 유지, 처분까지의 전체적인 소프트웨어 라이프사이클의 각 단계별로 수시로 변화되는 정보를 정확히 확인하고 관리하기가 쉽지 않다는 문제점이 있다. 따라서 본 논문에서는 이를 해결하기 위해서 개발된 점검용 시스템인 Inspector를 활용할 것을 제안한다. 제안된 점검서비스에는 패키지 소프트웨어의 특성을 고려한 검색기법이 구현되었고, 소프트웨어의 권리관리 정보를 표준화하였으며, 레지스트리 정보를 활용하였다. Inspector를 사용한 결과 PC 1대당 점검시간이 획기적으로 단축되었다. 이러한 효과 이외에도 소프트웨어를 효과적으로 관리함으로써 소프트웨어 구입비용을 절감할 수 있도록 지원하여 경영합리화에 이바지하는 것으로 나타났다. Even support-and-management efforts by government are enforced with the growing international restrictions for complying with global standard, not a few private enterprises are still suffering software management problems from lack of understanding the software asset management and carelessness of the software management. This is due to the ambiguous scope of software asset management as well as characteristics of software property such as invisibility, easiness of copy and installation. In other words, it is not easy for software managers to comply all the information throughout the software life cycle; from purchasing, procurement. distribution, preservation to disposition. Therefore, Inspector which has been developed for resolving these problems are proposed in this study. The inspection service consists of search algorithms adapted for software characteristics, standardization of software right management information, and practical use of registry information. Inspection time for a PC by using inspector make the inspection time much shorter. It is also shown that effective software management enables the enterprise to curtail software acquisition cost and to help rationalizing its business management.

서울지하철 일부 역사 내 부유 곰팡이 농도 및 환경요인

황성호,안재경,박재범,Hwang, Sung Ho,Ahn, Jae Kyoung,Park, Jae Bum 한국환경보건학회 2014 한국환경보건학회지 Vol.40 No.2

Objectives: We measured the concentrations of culturable airborne fungi (CAF) in enclosed environments at 16 underground subway stations of the Seoul Metro in 2013, and investigated the effect of environmental factors, including temperature, relative humidity, the number of passengers, and distance from the platform. Methods: The cultured fungi were identified by the lactophenol cotton blue (LPCB) staining method and were classified by observing the form, shape, and color of colony. A nonparametric analysis was used to determine if the differences in the concentrations of CAF were statistically significant. Results: The concentrations of CAF at the stations were the highest in station p ($367CFU/m^3$) with arange between 3 and $437CFU/m^3$. There was a significant correlation between CAF concentration and the distance from platform (r = 0.544, p < 0.01). Geotrichum spp. and Penicillium spp. were the predominant species. Conclusion: It is recommended that special attention be given during rush hour, which is in the morning (08:00-10:00) and in the early evening (18:00-19:00) to improve the indoor air quality of the subway stations.

차기호위함 및 검독수리함 운영유지비 추정

최봉완 ( Bong Wan Choi ),안재경 ( Jae Kyoung Ahn ) 대한설비관리학회 2010 대한설비관리학회지 Vol.15 No.3

In this study, attempts have been made to construct a standard cost specification structure fit for Korean Navy, and to estimate maintenance and operating costs of FFX, PKX-A, and PKX-B. The maintenance and operating costs of FFX along its whole life cycles, 30 years are estimated as 716.7 billion won via engineering analysis methods, while PKX-A, and PKX-B as 154.4billion won and 86.6 billion won, respectively. This study is expected to be able to provide meaningful decision making data for not only short and/or mid term operating planning but military budgeting.