• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2008.11a
• /
• pp.176-183
• /
• 2008

Recently, several large-scale Mega-Projects are being conducted. For these urban revitalization projects which requires many complex functions, the existing project management system based on single project level is limited in application. Therefore, our main objectives of this research are two 1) Develop a brand-new program management system(Prototype Ver 1.0) for mega-projects where various facilities are combined both horizontally and vertically. 2) Develop management strategies(Prototype Ver 1.0) based on the program level that enable the comprehensive management of a multiple various projects. The subtitles of this Research are i-PMIS(Program Management Information System) Development, Standardization & Optimization of Construction Life-Cycle Process, Comprehensive Project Cost & Process Management Technology, Effective and Optimized Integrated Performance Management Technology, and, we suggest to optimize the whole life cycle process, predict and respond to various risks, predict and control the process, the cost and the schedule, achieve maximum return on investment to the participating parties, and provide a brand-new Program-MIS including the visual-based web-portal platform to respond the changing business environments and decision making.

• Korean Journal of Remote Sensing
• /
• v.27 no.2
• /
• pp.181-190
• /
• 2011

Since the radar satellite missions such as TerraSAR-X and COSMO-SkyMed were launched in 2007, the spatial resolution of spaceborne SAR(Synthetic Aperture Radar) images reaches about 1 meter at spotlight mode. In 2011, the first Korean SAR satellite, KOMPSAT-5, will be launched, operating at X-band with the highest spatial resolution of 1 m as well. The improved spatial resolution of state-of-the-art SAR sensor suggests expanding InSAR(Interferometric SAR) analysis in urban monitoring. By the way, the shadow and layover phenomena are more prominent in urban areas due to building structure because of inherent side-looking geometry of SAR system. Up to date the most conventional algorithms do not consider the return signals at the frontage of building during InSAR phase and SAR intensity simulation. In this study the new algorithm introducing multi-scattering in layover region is proposed for phase and intensity simulation, which is utilized a precise LIDAR DSM(Digital Surface Model) in urban areas. The InSAR phases simulated by the proposed method are compared with TerraSAR-X spotlight data. As a result, both InSAR phases are well matched, even in layover areas. This study will be applied to urban monitoring using high resolution SAR data, in terms of change detection and displacement monitoring at the scale of building unit.

• The Journal of the Korea Contents Association
• /
• v.11 no.1
• /
• pp.317-328
• /
• 2011

Logistic system and methods of the transportation have been changed rapidly by the variety of the logistics environment. It is necessary to analyze the efficiency of Korean trucking companies for enhancing the competitive power and operating. This paper will describe the analysis of the efficiency of the trucking companies with DEA models. By the CCR and the BCC models, which are in parts of DEA model, the efficiency and RTS(Return To Scale) of forty two selected trucking companies were studied. It was also analyzed how the study the input-output variables were effected. And then, some of the forty two trucking companies were shown as the benchmark. As the result of analysis on the two models, seven companies won the score '1' on CCR model and seventeen companies on BCC model. Moreover, this study showed that reducing the total asset out of input variables, and raising the sales profit out of the output variables played a main role to increase the efficiency of the trucking companies highly.

• Journal of Navigation and Port Research
• /
• v.43 no.4
• /
• pp.256-263
• /
• 2019

The trade volume of Northeast Asian countries is increasing and with the advent of the 4th revolutionary era, minimizing the logistics costs of firm is becoming an important competitive factor. With respect to this, in 2006, the government introduced a certified Integrated logistics firm system to improve the competitiveness of local logistics firms and reduce the logistics costs of firms. They argued that the certified Integrated logistics firm system increased the reliability of logistics firms and increased the efficiency of the logistics industry. On the other side, they argue that the system puts a burden on firms and becomes a big business-oriented market consolidation. This study analyzed the efficiency of Warehousing firms using DEA model. The CCR, BBC efficiency and RTS (return to scale) of 15 Warehousing firms were evaluated. This study also suggested the Warehousing firms which can be benchmarked based on analyzed information.

• Journal of Sericultural and Entomological Science
• /
• v.14 no.2
• /
• pp.95-103
• /
• 1972

The major purpose of this study is to collect the information related on the aspects of economic efficiency for solving the problems which are faced by farmers and areas, and providing scientific facts to farmers and related institutions for further development of sericultural sector in Korea. In order for obtaining the related information 12 sample areas among 23 major sericultural farming areas and 30 farm units in each area are selected and analyzed in this study. The fold suevey is made by member of this study team and graduate students in the Department of Sericultural Science with a prepared questionnaires. Cross-section and regression analysis methods are employed for processing the data in this study. The major findings obtained are as followings. 1. Sericultural earnings per Tanbo is, on the average, 22, 752 won in new cultivated areas and 29, 403 won in ordinary ones. There are big difference in the size of earnings by areas, especially, 46, 968 won in Kumo mountain area, compared with 16, 798 won in Yeoju and Yichun areas. General trend is finded that small scale farming units are made higher earnings and operating their farms efficiently. 2. Cocoon production expences per Tanbo is 16, 737 won in new cultivated areas and 19, 802 won in ordinary areas. There are also big difference in farming expences, especially, 27, 389 won in Sudang area, compared with 11, 689 won in Emjin area. 3. Sericultural income per Tanto is 10, 664 won in ordinary areas and 6, 898 won in new cultivated areas. Farmers in Kumo mountain area make the highest income of 21, 164 won and lowest income of 1, 296 won in Sudang area. It can be generized that about 30-50 a sized farmers make higher income. 4. Land, labor and capital productivities estimated by fitting Cobb-Douglas functions in ordinary areas are higher than in new cultivated areas, especially, labor productivity is higher in ordinary areas. 5. Changsung, Kwangna, Yunsun and Kumo mountain areas are technically and economically efficient. Sudang and Mujinchang areas are technically successful but economically inefficient and Emjin and Honam areas are technically inefficient but economically efficient. YeojuYichun, Chunwon and West Kyongnam are technically and economically inefficient. Technical and economic improvement program should be implemented for these areas. 6. Estimated Internal Rate of Return (IRR) on capital investment in Chongwon are is 23.5 percent. It is economically feasible, if we consider 20 percent of opportunity cost of capital in our economy.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.11 no.1
• /
• pp.51-56
• /
• 2012

Purpose: Golf is a popular sports activity after total knee arthroplasty in old age patients. We evaluated golf and implant loosening through the radiologic method. We also evaluated correlation of patterns of golf activity and clinical outcome to suggest guidelines to the patients. Materials and Methods: We carried out a retrospective case-control study of 80 patients (80 knees) who underwent TKR between 2005 and 2008, and followed up more than 3 years. We divided patients who played golf after TKR as a study group and who did not participate sports activities as a control group. We calculated the sum of width of radiolucent line in 7 sections around femoral component, 7 sections around tibial components and 5 sections in patella component using American Knee Society Roentgenographic Evaluation and Scoring system respectively. The inclusion criteria, was BMI (body mass index) was between 25 and $30kg/m^2$, and UCLA activity-level rating System score was between 5 and 8. We also got the information of patients' patterns of golf activities such as 1. the interval from surgery to return to golf activity. 2. the frequency of golf activities 3. using spike or cart. We obtained the information from patient's questionnaire and telephone interview. We compared with the VAS (visual analogue scale) respectively. And handicaps and driving distance was evaluated as well. Results: The study group's mean sum of radiologic score was 0.84 mm and 0.69 mm in control group. This is not statistically significant (p=0.22). Too early returning to golf (p=0.01) and left knee replacement (p<0.01) were statistically significant factors affecting clinical outcomes of golf activities after total knee arthroplasty. Conclusion: We concluded that golf activities after total knee arthroplasty is not correlated with radiographic loosening, and we need to give an explanation to the patients about increased pain when returing to golf too early and left side arthroplasties.

• The Journal of the Korea Contents Association
• /
• v.9 no.4
• /
• pp.323-330
• /
• 2009

This study measures the relative efficiency and productivity change of the Korean Life Insurance Firms using DEA model and Malmquist Index for 2004-2007. The main results of this study can by summarized as follows. First, in case of efficiency of CCR for 2004-2007, the number of efficient firms(CCR value is one) are six firms, five firms, four firms, seven firms respectively. Second, in case of efficiency of BCC for 2004-2007, the number of efficient firms(BCC value is one) are eight firms, nine firms, ten firms, twelve firms respectively. Third, In case of return to scale for 2004-2007, DRS are nine firms and IRS are two firms, DRS are five firms and IRS are five firms, DRS are five firms and IRS are four firms, DRS are five firms and IRS are two firms respectively, Fourth, Malmquist Index representing productivity change for 2004-2007 are 1.12 in 2004-2005, 0.97 in 2005-2006, 1.05 in 2006-2007.

• Journal of Digital Contents Society
• /
• v.15 no.1
• /
• pp.19-27
• /
• 2014

In order to estimate the life of 2,5 inch HDD which is adopted by PC environment, make the test plan which reflect the failure mode of market, make the test model of accelerated life test which reflect the stress of temperature. after an analysis of the environment of PC using, test procedure was decided that operation was write 50 % and read 50 %, and then access method was sequential 50 % and random 50%. The acceleration life test was executed on condition that temperature was $50^{\circ}C$ and $60^{\circ}C$, performance was 95 % in max performance, test time was 1000 hours. by the test of goodness of fit of anderson-darling of the failure data during test, it was confirmed that the distribution of failure fellow weibull. test for shape and scale was equal, and shape parameter was 0.7177, characteristic life was 429434 hours at normal user condition($30^{\circ}C$) by the analysis of weibull-arrhenius modeling. It made no difference about the statistics when equality test was executed. The activation energy was 0.2775eV. In analyzing between the failure samples of acceleration test and the samples of market return even though there is detail difference about the share of failure mode, the rank of share was almost same. This study suggest the test procedure of acceleration test of 2.5 inch HDD in PC using environment, and help the life estimation at manufacture and user.

• Journal of Korea Water Resources Association
• /
• v.43 no.8
• /
• pp.733-745
• /
• 2010

Seasonality of hydrologic extreme variable is a significant element from a water resources managemental point of view. It is closely related with various fields such as dam operation, flood control, irrigation water management, and so on. Hydrological frequency analysis conjunction with partial duration series rather than block maxima, offers benefits that include data expansion, analysis of seasonality and occurrence. In this study, nonstationary frequency analysis based on the Bayesian model has been suggested which effectively linked with advantage of POT (peaks over threshold) analysis that contains seasonality information. A selected threshold that the value of upper 98% among the 24 hours duration rainfall was applied to extract POT series at Seoul station, and goodness-fit-test of selected GEV distribution has been examined through graphical representation. Seasonal variation of location and scale parameter ($\mu$ and $\sigma$) of GEV distribution were represented by Fourier series, and the posterior distributions were estimated by Bayesian Markov Chain Monte Carlo simulation. The design rainfall estimated by GEV quantile function and derived posterior distribution for the Fourier coefficients, were illustrated with a wide range of return periods. The nonstationary frequency analysis considering seasonality can reasonably reproduce underlying extreme distribution and simultaneously provide a full annual cycle of the design rainfall as well.

• Journal of the Korean Orthopaedic Association
• /
• v.56 no.2
• /
• pp.157-163
• /
• 2021

Purpose: Xanthomatosis of the Achilles tendons is rare. In some patients, however, the lesions in the Achilles tendon need to be removed, which may be painful and disfiguring. While studies of successful surgical outcomes for the total resection and reconstruction of the Achilles tendon have been reported, reconstruction surgery has a technical challenge, and extended surgical exposures are required. This study analyzed five cases of bilateral xanthoma of the Achilles tendon, which was treated surgically using a wedge-shaped tendon-sparing approach to eliminate the need for tendon reconstruction. Materials and Methods: From July 2010 to May 2018, five patients with xanthomatosis in both Achilles tendons underwent wedge-shaped tendon preserving surgery. The average age was 49 years (range, 40-55 years), and the follow-up period was 21.4 months (range, 12-31 months). The patients consisted of three males and two females. Complications related to surgery were recorded. The outcome measures included the range of motion of the ankle joint, American Orthopaedic Foot and ankle Society (AOFAS) ankle/hindfoot score, and visual analogue scale (VAS) for overall satisfaction at the last follow-up. The availability of a single-limb heel raise and returning time to work were also measured. Results: Wound dehiscence that did not require secondary surgery was noted in one patient. At the last follow-up, the range of motion of the ankle joint was normal in all patients. The mean AOFAS ankle/hindfoot score was 91 (range, 85-96) and the VAS for the overall satisfaction ranged from 8 to 10. The average time between surgery and return to work was 27.6 days (range, 17-58 days) and all patients could perform a single-limb heel raise test. Conclusion: The tendon-sparing technique, which can preserve the anatomical functioning of the Achilles tendon, could be an excellent surgical approach because it has very promising functional and cosmetic surgical outcomes in patients with Achilles tendon xanthomatosis.