• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.20-32
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• 2008

Runoff characteristics of the Oedocheon in Jeju island were investigated using the long-term stream stage monitoring data. At the Cheonah valley in the upstream area and Oedocheon downstream, annual runoff occurred 21 and 12 times, respectively, and their average runoff periods were 21 days and 12 days, respectively. Stream stage response time to rainfall was 4 hours, and storm-water transfer from the upstream, Cheonah valley, to the Oedocheon downstream took about 2 hours. The stream discharge measurements had been carried out from Feb. 2004 to Jul. 2005, and showed that normal discharge of the Oedocheon was 0.39 $m^3$/sec in average. Stage-discharge curves were developed to estimate base flow (normal discharge) and (direct) surface runoff. The base flow separations by a numerical filtering technique illustrated that annual surface runoff and base flow accounted respectively for 31.8${\sim}$36.5%, 63.5${\sim}$68.2% of the total stream discharge.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.65-71
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• 2017

It is true that there is a possibility of distortion in the statistical surveys or actual surveys depending on which investigator, what purpose, and how research method. Even statistical results are more likely to be 'lying', and statistics on crime or delinquent are sometimes referred to as 'whopper'. There are many reasons for not trusting statistics on crime or delinquent, but one of the main causes is the existence of a hidden crime or an unreported crime. In order to overcome these hidden crime problems, victim surveys or self-report surveys are being used. However, this method also has the problem of underreporting or overreporting depending on the type of crime. Because investigations into crime, delinquency, and deviant behavior are very sensitive, the subjects have a psychological burden. A randomized response model has been developed and used in the field of statistics as a way to induce a true answer to the sensitive content which is burdensome to reveal the experiences of the survey subjects. This technique is a very useful way to solve the problems of victim surveys or self-report surveys. Nevertheless, there are very few cases in the field of criminology in Korea. Therefore, in order to examine the applicability of the randomized response model in the field of criminology, this study used the randomized response model to actually measure the content of prostitution for college students and the effectiveness of the randomized response model was confirmed.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.456-462
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• 1993

Parboiling, a popular technology used to protect rice from nutrient loss during milling and to increase the shelf-life of rice, was applied to barley kernels, and its effect on nutrient retention and chemical composition was evaluated. Before 36 days after ear emergence, barley kernels showed water content higher than 40%, and parboiling without presoaking resulted in at least 43% of gelatinization degree. This implies that soaking, an important step of parboiling, is dispensable for barley at milky stage. Parboiling did make little change in the appearance of the kernel after 31 days from ear emergence. Nonreducing sugars such as sucrose and raffinose remained unchanged while reducing sugars of barley was decreased by parboiling, with exception that maltose increased. Pearling led to decrease in crude protein, fat, fiber and minerals of barley sampled and parboiled on 36th day from ear emergence. Free sugars in the parboiled barley also was reduced with increasing pearling rate. Vitamin $B_1$ content of the parboiled barley was $260\;{\mu}g\;per\;100\;g$ as dry basis at 50% pearling rate, compared to $36\;{\mu}g$ for raw barley at same pearling rate. Thus parboiling appeared to be very effective in the retention of vitamin $B_1$ during pearling.

• Analytical Science and Technology
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• v.31 no.3
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• pp.122-133
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• 2018

In this study, groundwater quality data measured for 11 years from 2006 to 2016 were analyzed statistically for 101 civil defense emergency water supply facilities (CDEWSF) in the Gwangju area. The contamination level was quantified into four grades by using excess drinking water quality standards, average concentration analysis, and tendency analysis results for each facility. On the basis of this approach, the groundwater contamination degree of each item was evaluated according to land use status, installation year, depth, and geological distribution. The contamination grade ratios, which were obtained by analyzing three contamination indicators (water quality exceeded frequency, average concentration analysis, and trend analysis) for 15 items on statistically significant of civil defense emergency water was relatively high, in the order of Turbidity (51.5 %) > Color (32.7 %) > Nitrate nitrogen (28.7 %) > Hardness (25.7 %). As a result of the contamination grade analysis, except for the items of Turbidity, Color, and Nitrate nitrogen, the contamination levels were distributed in various degrees from "clean (0)" to "seriously contaminated (3)." Regarding the contamination grade of 12 items, 25 % of the total were classified as "possibly contaminated (1)," and 75 % were rated "clean (0)." The four items (Turbidity, Color, Nitrate nitrogen, and Hardness) for which contamination indication rate were evaluated as "high" by the were visualized on a contamination map.

• Archives of design research
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• v.16 no.2
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• pp.375-384
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• 2003

This study is on the strategy for establishing successful corporate brand image, by understanding the need for increasing brand value based on the level of brand recognition. In order to carry this out, the PICS (Product Image Concentration System) is suggested, which includes Brand Image Analysis on a high-level, Product Image Programming based on the result of the image analysis, and Product Image Coherency Assessment and Management, resulting in setting up a guideline for gaining competitive advantage and brand management. Brand Image Analysis is a method that utilizes image association to understand brand disposition by analyzing the association pattern among available visual materials to measure the corporate and brand image inclinations. As the next step, Product Image Programming establishes design philosophy and principles based on the analysis of brand image, and the Visual Programming is a process for visualizing the intended product image direction. Lastly, Product Image Coherency Assessment examines whether to incorporate design philosophy and principles or not to arrive at an agreed evaluation criteria for developing designs coherent with the brand image. The PICS (Product Image Concentration System) is a practical method for increasing a company' competitive advantage and managing brand. The expectation on this system is to provide a guideline for applying brand image in design process more objectively. For further study, diversification of image spectrum based on expressive keywords and comparative analysis on images as well as a product image interpretation program to understand the order of visual materials will be necessary.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.101-101
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• 2011

현재 국내에서 시행되고 있는 '4대강 살리기 사업'은 하천에서 발생하는 홍수 및 가뭄재해방지를 위한 다양한 공학적 노력을 시도하고 있다. 특히 안정적인 수위 및 유량확보와 홍수방지를 위한 보(weir)가 4대강 유역에 16개 설치되고 있다. 이러한 보 구간에는 고정보와 가동보가 복합적으로 설치되고 있으며 가동보는 그 형상과 운영방식에 따라 다양한 설계방안이 적용되었다. '4대강 살리기 사업' 중 낙동강 23공구의 강정보 공사 구간에는 원호형태의 측면 형상을 갖는 라이징 섹터게이트(Rising sector gate)가 적용되었다. 라이징 섹터게이트는 구조물의 높이가 낮고 수문의 개폐장치가 수문피어 구조물 내에 설치되어 경관이 우수하며, 구조가 간단하여 비체와 수류의 안정성이 뛰어나기 때문에 4개의 공사구간에 적용되었다. 따라서 본 연구에서는 강정보의 가동보 구간 2문 중 1문을 1/100 축척으로 제작하여 가변경사 개수로에 설치하고, 홍수 빈도별 상류 유량 조건과 하류단 수위조건으로 케이스를 정하여 실험을 수행하였다. 본 실험에서 사용한 개수로 장치는 너비 0.6 m, 높이 0.8 m, 그리고 길이 15.0 m(측정가능 구간, 헤드탱크와 테일게이트 부제외)의 개수로 실험장치이다. 측부는 모두 강화유리로 되어 육안관찰 및 계측 시 용이하게 제작되었으며, 순환식 유량 공급장치를 구축하여 수로의 하부에 설치된 유량탱크로부터 계속적으로 순환하도록 설계되었다. 또한 수로 하단으로부터 상단방향으로 약 33 m 지점에 전동 유압식 Jack screw 2기가 설치되어 경사도를 조절할 수 있도록 제작되었다. 유량조절용 판넬의 제어기판에는 디지털 경사계가 설치되어 있기 때문에 보다 정확한 경사도의 조절이 가능하다. 보 모형의 총연장은 53 cm이며 폭은 45 cm이다. 섹터게이트의 게이트부분은 직경 15 cm로 설계하였다. 문주부분을 포함한 모든 모형은 아크릴로 제작하며 레이저의 주사를 방해하지 않으며 투과율을 최대로 할 수 있도록 고강도의 아크릴을 가장 얇게 하여 중공형태를 채택하였다. 실험조건은 우선 보의 운영방안에 따라 게이트의 4가지 개방도를 설정하였고, 특히 평수위조건에서는 보의 상류부에 퇴적된 퇴적물의 세척을 위한 flushing 운영개방도 포함되어 있다. 홍수시에 대한 유량조건은 2년 빈도에 해당하는 유량을 수문의 비율과 상사법칙에 따라 설정하였으며 하류단 수위조건도 동일한 조건에 대한 값을 채택하여 적용하였다. 유동장의 해석을 위해서는 비접촉식 계측방법인 PIV(Particle Image Velocimetry) 시스템을 채택하여 2차원(x-z 방향) laser sheet를 생성하고 주입된 particle에서 반사된 변위(displacement) 정보를 상호상관(cross-correlation)기법으로 유동장을 계산하였다. 또한 수리모형과 동일한 지형격자를 구축하여 3차원 CFD 프로그램인 FLOW-3D로 계산하여 결과를 비교하였다. 특히 flushing 운영방안에 대한 게이트부의 개방도를 세가지(30, 45, $60^{\circ}$)로 구분하여 모의하였고, 적절한 개방도를 제안하고자 하였다. 실험결과는 우선 4가지 운영방안에 대한 가동보 주변에서의 유속장을 파악하였고, 최대유속의 발생위치의 변화를 확인할 수 있었다. 그리고 이에 따른 보의 바닥에서 최대유속이 발생할 경우, 하상보호공 위치와 거리 등에 대해서 분석하였다. 이를 통해 가동보 운영에 따른 다양한 유속구조를 파악할 수 있게 되며 구조적 안정성 확보를 위한 검증자료로 활용될 수 있을 것으로 예상된다. 향후, 가동보 운영방안 중 수세효과(flushing effect)에 대한 효과분석을 위해 게이트부 상류구간에 적절한 입경과 비중의 퇴적물질을 설치하는 연구와 상류부에서의 유입유사농도 및 시간변화에 따른 퇴적에 관한 연구를 수행할 계획이다.

• Journal of the Korean Society for information Management
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• v.30 no.1
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• pp.111-129
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• 2013

This study analyzed the process of multimedia services and indexed the core quality characteristics through the tools employed in 'Define' and 'Measure' steps of the 6 Sigma DMAIC methodology. To achieve the goal, as a case study of 'S' University Central Library, first, brainstorming technique was used to tap the librarians, second, interview with the half-time student workers, third, user's opinion on homepage was analyzed and lastly, the interview with the users. This study also drew some potential causal factors which would likely to affect the multimedia service using Process Map and C&E Diagram. Those factors were prioritized using X-Y matrix and Pareto Chart. This study revealed 14 factors affecting multimedia services: 'presence/absence of the persons who are in charge of selection', 'cycle of selection materials', 'presence/absence of seperated multimedia room', 'materials arrangement method', 'notification of popular materials', 'notification of documents arrivals', 'methods of noticing new arrivals', 'methods of ordering materials', 'cycle of checking order status', 'types of persons requesting materials', 'methods of requesting materials', 'checking of the status of the returned materials', 'methods of noticing materials in housed', and 'methods of ways to return overdue materials'.

• Environmental and Resource Economics Review
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• v.15 no.4
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• pp.673-692
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• 2006

In order to test for the dynamic optimality condition for the use of nonrenewable resource, it is necessary to estimate the shadow value of the resource in situ. In the previous literatures, a time series for in situ price has been derived either as the difference between marginal revenue and marginal cost or by differentiating with respect to the quantity of ore extracted the restricted cost function in which the quantity of ore is quasi-fixed. However, not only inconsistent estimates are likely to be generated due to the nonmalleability of capital, but the estimate of marginal revenue will be affected by market power. Since firms will likely fail to minimize the cost of the reproducible inputs subject to market prices under realistic circumstances where imperfect factor markets, strikes, or government regulations are present, the shadow in situ values obtained by estimating the restricted cost function can be biased. This paper provides a valid methodology for checking the dynamic optimality condition for a nonrenewable resource by using the input distance function. Our methodology has some advantages over previous ones: only data on quantities of inputs and outputs are required; nor is the maintained hypothesis of cost minimization required; adoption of linear programming enables us to circumvent autocorrelated errors problem caused by use of time series or panel data. The dynamic optimality condition for domestic coal mining does not hold for constant discount rates ranging from 2 to 20 percent over the period 1970~1993. The dynamic optimality condition also does not hold for variable rates ranging from fourth to four times the real interest rate.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.1
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• pp.23-34
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• 2012

Space launch vehicles are designed to fly according to the elaborate pre-determined path. However, if a vehicle went out of the planned trajectory or its thrust terminated abnormally, or if a free-fall atmospheric reentry vehicle tracked by a tracking sensor became impossible to be measured, it is required to attempt to track by a another track equipment or estimate its impact point rapidly. In this paper a new algorithm is proposed, named the ITS-EKF combined with the Integrated Track Splitting (ITS) algorithm and the Extended Kalman Filter (EKF) to obtain the location information of a ballistic projectile without thrust, create its track and maintain it in an environment with clutter. For the reentry vehicle, the track performance is to be verified and the impact point is estimated by applying the simulation through ITS-EKF algorithm. To ensure the proposed algorithm's adequacy, by comparing the track performance and impact point distribution by the ITS-EKF with those of ITS-PF combined with ITS and Particle Filter (PF), it is confirmed that the ITS-EKF algorithm can be used an effective real-time On-line impact point prediction.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.283-292
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• 2005

Ionosphere is deeply coupled to the space environment and introduces the perturbations to radio signal because of its electromagnetic characteristics. Therefore, the status of ionosphere can be estimated by analyzing the GPS signal errors which are penetrating the ionosphere and it can be the key to understand the global circulation and change in the upper atmosphere, and the characteristics of space weather. We used 9 GPS Continuously Operating Reference Stations (CORS), which have been operated by Korea Astronomy and Space Science Institute (KASI) , to determine the high precision of Total Electron Content (TEC) and the pseudorange data which is phase-leveled by a linear combination with carrier phase to reduce the inherent noise. We developed the method to model a regional ionosphere with grid form and its results over South Korea with $0.25^{\circ}\;by\;0.25^{\circ}$ spatial resolution. To improve the precision of ionosphere's TEC value, we applied IDW (Inverse Distance Weight) and Kalman Filtering method. The regional ionospheric model developed by this research was compared with GIMs (Global Ionosphere Maps) preduced by Ionosphere Working Group for 8 days and the results show $3\~4$ TECU difference in RMS values.