• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.345-345
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• 2022

기후변화의 영향으로 도시하천의 홍수피해가 증가추세이며, 여름철 돌발호우 발생으로 하천내 고립사고 피해가 빈번히 발생하고 있다. 특히 중·소규모 도시하천은 홍수유출 도달시간이 매우 짧고 수위가 급격히 상승하여 돌발호우에 매우 취약하므로, 정확한 홍수발생 가능성 및 시점 예측을 통한 신속한 홍수 예·경보가 필요하다. 따라서 본 연구에서는 강우강도, 강우시간분포, 강우지속시간 등에 따른 홍수발생여부 뿐만 아니라 홍수발생시간을 예측할 수 있는 Flooding Time Nomograph (FTN)를 개발하였다. 본 연구의 대상유역은 도림천 유역으로, FTN 개발을 위하여 도시하천의 강우-유출모의에 적합한 XP-SWMM 모형을 구축하여 활용하였다. 또한 Huff의 4분위 강우분포를 이용한 다양한 형태의 가상 강우시나리오를 설정하여 강우유출모의를 수행하였으며, 모의결과를 기반으로 강우강도와 홍수발생시간의 관계식을 산정하여 FTN을 생성하였다. 실제 호우 사상에 대한 관측 홍수발생시간과의 비교를 통해 FTN의 적용성을 평가한 결과, 상관계수 CC=0.8, NSE=0.6 이상으로 높은 정확도를 보이는 것으로 나타났으며, 강우발생 시 둔치수위 도달 홍수위 기준 최대 30분의 사전 대피시간 확보가 가능함을 확인하였다. 따라서 본 연구에서 개발한 FTN을 이용한 도시하천의 홍수 예·경보 시스템 구축의 경우, 강우정보에 따른 홍수발생여부 및 홍수발생시간을 합리적으로 판단할 수 있어, 둔치 수위 예·경보 등 보다 신속한 상황대응이 가능할 것으로 사료된다.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.792-800
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• 2012

The study was performed to simulate the reduction efficiency of suspended solids (SS) for cultivated land located at riverine area at the Namhan River and the Bukhan River watershed sites (site A, B, C) under the rainfall conditions using HUFF & SCS UH-based VFS Design module of Web GIS-based VFSMOD System. The study indicates that the field 5% sloped, located at Bukhan River watershed (site A), requires at least 0.5 m width of Vegetative Filter Strip (VFS) to reduce 70% of SS while the field 10% sloped requires the at least 1.0~1.5 m width of VFS to reduce 70% SS, under the condition 106.2 mm of rainfall event and bell pepper or corn of crops. Against the conditions 95.1 mm of rainfall event and sweet potato or soy bean of crops, the field 5% sloped, located at Namhan River watershed (site B) requires at least 0.5 m width of VFS to reduce 70% of SS while the field 10% sloped requires at least 1.0 m width of VFS to reduce 50% SS. The crops sweet potato and soy bean are cultivated in the site C, located at Namhan River watershed, 1 m of VFS is capable of 64.0% and 62.0% of SS reduction against 102.6 mm and 151.2 mm rainfall conditions respectively, for the 5% sloped field. The result supports that VFS is one of most potential methods to reduce SS from cultivated area, which is environment-friendly hydrologic structure. The VFS design, however, needs to be simulated before its installation in the field, the simulation needs to consider not only various characteristics of the field but also different conditions affecting the VFS, using a model capable to consider a lot of factors.

• Journal of Distribution Science
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• v.7 no.3
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• pp.5-24
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• 2009

In the retail management, store location has an important influence like business skills. The reason for failure to selecting location is that the market analysis model is not popular in business field. It gets worse in supermarket industry. Currently, store developers are relying on simple statistics and the sixth sense as market analysis techniques. lt proves that the market analysis model is not distributed well in the field. This market analysis model can apply to medium and small business market using an existing market analysis model, broad market model. And its study outcome can be theorized as a result. Converse's new retail model can be used as to analyze junction market. Pareto_Huff model can also be used to compute shopping probability. To do so, this study can be divided into walking distance market and driving distance market as a model market. Also it examines industry type such as SM and SSM. By taking consumer survey, condition of consumers to select store will be counted in shopping probability so that it improves the objectivity and reliability. Through this process, derived study outcome can be a new estimated revenue model for practical application of selecting store location in large and medium-sized supermarket.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.115-124
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• 2019

In a climate change environment where heat damage and drought occur during a rainy season such as in 2018, a vegetation-based LID system that enables disaster prevention as well as environment improvement is suggested in lieu of an installation-type LID system that is limited to the prevention of floods. However, the quantification of its performance as against construction cost is limited. This study aims to present an experiment environment and evaluation method on quantitative performance, which is required in order to disseminate the vegetation-based LID system. To this end, a 3^rd quartile huff time distribution mass curve was generated for 20-year frequency, 60-minute probable rainfall of 68mm/hr in Cheonan, and effluent was analyzed by recreating artificial rainfall. In order to assess the reliability of the rainfall event simulator, 10 repeat tests were conducted at one-minute intervals for 20 minutes with minimum rainfall intensity of 22.29mm/hr and the maximum rainfall intensity of 140.69mm/hr from the calculated probable rainfall. Effective rainfall as against influent flow was 21.83mm/hr (sd=0.17~1.36, n=20) on average at the minimum rainfall intensity and 142.27mm/hr (sd=1.02~3.25, n=20) on average at the maximum rainfall intensity. In artificial rainfall recreation experiments repeated for three times, the most frequent quartile was found to be the third quartile, which is around 40 minutes after beginning the experiment. The peak flow was observed 70 minutes after beginning the experiment in the experiment zone and after 50 minutes in the control zone. While the control zone recorded the maximum runoff intensity of 2.26mm/min(sd=0.25) 50 minutes after beginning the experiment, the experiment zone recorded the maximum runoff intensity of 0.77mm/min (sd=0.15) 70 minutes after beginning the experiment, which is 20 minutes later than the control zone. Also, the maximum runoff intensity of the experiment zone was 79.6% lower than that of the control zone, which confirmed that vegetation unit-type LID system had rainfall runoff reduction and delay effects. Based on the above findings, the reliability of a lab-level rainfall simulator for monitoring the vegetation-based LID system was reviewed, and maximum runoff intensity reduction and runoff time delay were confirmed. As a result, the study presented a performance evaluation method that can be applied to the pre-design of the vegetation-based LID system for rainfall events on a location before construction.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.585-593
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• 2013

This study aims to investigate inundation characteristics such as inundated area, inundation depth according to variation in return period of design rainfall and to draw a comparison between the inundation characteristics by adapting design storm using dual-drainage model. Lidar data is used to construct terrain data with $1m{\times}1m$ resolution in Cheongju. The designed storm by return periods(10year, 30year, 50year and 200year) are acquired from Intensity Duration Frequency curve, which are distributed in 5 minutes interval using Huff's method. As a results, the inundation volume is linearly increased, but inundated area is gradually increased in accordance with swell of return period for design storm. On the other hands, as a result of calculating discharge capacity for each points, deficit of discharge capacity is not observed using designed storm of 10 year return period at every points. If the return period is increased up more than 10 years, both the deficit of discharge capacity for each PT and entire study area are enlarged drastically.

• Journal of Korea Water Resources Association
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• v.45 no.10
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• pp.1035-1041
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• 2012

This paper is on the decision of design magnitude for flood control of urban basin, based on flooding characteristic values. In Korea, a design magnitude for flood control is established based on peak discharge of the outlet of basin. However, this method is inappropriate in an urban basin because sewerage only can flow out as much as it could and other discharge overflow to basin. In order to calculate a design magnitude for flood control of an urban basin, flooding characteristic values (peak discharge of pipe, average flooded depth, maximum flooded depths of an important point, flooded area, flooded volume, flooded time) were used as a tool. Using the Gwanghwamun Square as an example, a methodology was proposed that used XP-SWMM 2010 model as a platform to predict urban flood disaster. It can help other local government and residents to better understand, prepare for and manage a flood in urban environments.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.244-248
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• 2008

홍수량산정과 관련하여 국내 실무에서 어려움을 겪는 가장 큰 문제는 설계강우의 결정이다. 설계강우와 관련하여 세부적으로 살펴보면 크게 강우의 시간분포(예를 들면 Huff, Mononobe, 교호블록 등), 강우의 공간분포(ARF 적용 등)의 두가지 문제로 집약될 수 있다. 본 논문에서는 강우의 시간분포와 공간분포에 관련된 문제를 동시에 해결할 수 있는 방법으로 교호블록형 이동설계강우에 대한 적용 방법을 제안하고 그 적용성을 검토하였다. 본 연구에서는 국내에서 연구된 강우의 이동속도와 여름철 저기압기단과 태풍의 이동속도 등을 감안하고 나아가 표준화된 방법으로서 적용의 용이성 등을 고려하여 강우의 이동속도 $\upsilonv\;=\;10km/hr$, $\Delta\;=\;10km$ 간격으로 직사각형 띠 형태로 연결되는 이동강우를 채택하였다. 강우의 이동방향은 서$\rightarrow$동, 남$\rightarrow$북, 남서$\rightarrow$북동의 3가지 방향을 기준하였다. 유역특성 이동강우 3가지(서$\rightarrow$동, 남$\rightarrow$북, 남서$\rightarrow$북동)와 정체강우 2가지(유역평균, 유역특성) 등 총 5가지 경우에 대하여 100년 빈도 48시간 설계강우를 한강유역의 분포형 강우-유출 모형에 적용하여 그 결과를 분석하여 다음과 같은 결론을 얻었다. (1) 정체강우에 있어서 유역평균강우와 유역특성강우에 대한 홍수량 비교를 통하여 해당 유역의 홍수량과 강우량과의 관계를 판단할 수 있었다. 충주댐유역의 경우 한강유역 전체에 대한 평균 100년 빈도 강우가 내린다면 23,000cms까지도 발생할 수 있으나 충주댐유역 100년 빈도에 해당하는 강우량으로는 18,000cms 정도의 홍수량이 발생하여 상대적으로 강우량이 적은 지역으로 나타났다. 반면에 임진강하류부는 한강유역평균강우 보다 더 많은 강우량이 내림으로 인하여 홍수량이 증가하는 유역임을 알 수 있었다. (2) 이동설계강우에 대하여 분석한 결과 유역이 매우 크거나 매우 작으면 강우의 이동방향에 대한 영향이 상대적으로 감소해가는 반면에 중규모 유역에서 상대적으로 영향이 크게 나타났다. 한강하구와 같은 대유역의 경우 여러 방향의 유역들이 유출에 기여하기 때문에 강우의 이동방향에 대한 영향이 상쇄되기 때문으로 분석되었다. 반면에 매우 작은 소유역의 경우는 전체 유역이 단일 강우강도의 영향권에 놓이게 되므로 이동방향의 영향이 나타나지 않는 것으로 나타났다. (3) 정체설계강우와 이동설계강우의 비교를 통하여 한강하구와 같은 대유역의 이동강우에 대한 ARF 효과를 간접 측정할 수 있었다. (4) 정체설계강우 보다 이동설계강우가 오히려 더 큰 첨두홍수량을 발생시키는 유역들이 있었다. 이와 같은 수문현상은 기존 정체형 설계강우로는 분석이 어려운 현상으로서 강우와 유역특성에 대한 보다 심층적인 연구 필용성을 제기하고 있다.

• The Korean Journal of Nuclear Medicine
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• v.1 no.2
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• pp.61-74
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• 1967

In order to confirm whether acquired immunity or resistance can be developed by the repeated hookworm infections, the 150 mature actively moving filariform ancylostoma duodenale larvae obtained from the severe hookworm anemia patients were orally given to 8 healthy volunteers in three divided doses, 50 in each, at 5 day interval. Also the hematological changes as well as several ferrokinetics using $^{59}Fe$ were done and were compared with 10 controls. The clinical symptoms and signs were checked every day for the first 3 weeks and then twice weekly until the end of the experiment. The appearance of the ova in the stool was examined by the formalin ether method and the ova was counted by the Stoll's method. The following laboratory tests were done: 1) Red blood cell count, venous blood hematocrit(micromethod), hemoglobin count (cyanomethemoglobin method) were checked every 5 to 7 day interval. 2) Plasma iron concentration (Barkan's modified method) was determined every 2 to 3 week interval. 3) Radioisotope studies: a) Ferrokinetics: Huff et al and Bothwell's method were applied. Erythropoietic Index (% of normal)=$\frac{Subject's\;turnover/100ml\;whole\;blood{\times}100}{Average\;normal\;turnover/100ml\;whole\;blood}$ of the gastrointestinal absorption of iron: Radioiron($^{59}Fe$) balance b) Quantitative measurement method was applied. c) Determination of the plasma erythropoietin activity: Fried's method was applied. Following were the results: 1) The serum iron level was lower. The red cell volume was decreased, but with relative increase of plasma volume. 2) The plasma iron disappearance time was accelerated and the plasma iron turnover rate was decreased. The red cell iron turnover rate was markedly increased, while all of the red cell iron concentration, circulating red cell iron. plasma iron pool were decreased. The daily iron pool turnover and red cell renewal rate were increased. 3) The erythropoietic index, erythropoietin activity and intestinal absorption of iron($^{59}Fe$) were markedly increased. 4) The infectivity was $9.8{\pm}1.31%$ which was lower than that observed in the single infection. 5) From these observations, it is concluded that the hookworm anemia is essentially iron deficieny in its origin and some immunity acquisition is possible with repeated infections.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6B
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• pp.503-512
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• 2009

Watershed models, which are a tool for water cycle mechanism, are classified as the distributed model and the lumped model. Currently, the distributed models have been more widely used than lumped model for many researches and applications. The lumped model estimates the parameters in the conceptual and empirical sense, on the other hand, in the case of distributed model the first-guess value is estimated from the grid-based watershed characteristics and rainfall data. Therefore, the distributed model needs more detailed parameter adjustment in its calibration and also one should precisely understand the model parameters' characteristics and sensitivity. This study uses Jungnang basin as a study area and $Vflo^{TM}$ model, which is a physics-based distributed hydrologic model, is used to analyze its parameters' sensitivity. To begin with, 100 years frequency-design rainfall is derived from Huff's method for rainfall duration of 6 hours, then the discharge is simulated using the calibrated parameters of $Vflo^{TM}$ model. As a result, hydraulic conductivity and overland's roughness have an effect on runoff depth and peak discharge, respectively, while channel's roughness have influence on travel time and peak discharge.

• Journal of Global Scholars of Marketing Science
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• v.19 no.3
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• pp.49-61
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• 2009

This article provides training exercises for executives into interpreting subroutine maps of executives' thinking in processing business and industrial marketing problems and opportunities. This study builds on premises that Schank proposes about learning and teaching including (1) learning occurs by experiencing and the best instruction offers learners opportunities to distill their knowledge and skills from interactive stories in the form of goal.based scenarios, team projects, and understanding stories from experts. Also, (2) telling does not lead to learning because learning requires action-training environments should emphasize active engagement with stories, cases, and projects. Each training case study includes executive exposure to decision system analysis (DSA). The training case requires the executive to write a "Briefing Report" of a DSA map. Instructions to the executive trainee in writing the briefing report include coverage in the briefing report of (1) details of the essence of the DSA map and (2) a statement of warnings and opportunities that the executive map reader interprets within the DSA map. The length maximum for a briefing report is 500 words-an arbitrary rule that works well in executive training programs. Following this introduction, section two of the article briefly summarizes relevant literature on how humans think within contexts in response to problems and opportunities. Section three illustrates the creation and interpreting of DSA maps using a training exercise in pricing a chemical product to different OEM (original equipment manufacturer) customers. Section four presents a training exercise in pricing decisions by a petroleum manufacturing firm. Section five presents a training exercise in marketing strategies by an office furniture distributer along with buying strategies by business customers. Each of the three training exercises is based on research into information processing and decision making of executives operating in marketing contexts. Section six concludes the article with suggestions for use of this training case and for developing additional training cases for honing executives' decision-making skills. Todd and Gigerenzer propose that humans use simple heuristics because they enable adaptive behavior by exploiting the structure of information in natural decision environments. "Simplicity is a virtue, rather than a curse". Bounded rationality theorists emphasize the centrality of Simon's proposition, "Human rational behavior is shaped by a scissors whose blades are the structure of the task environments and the computational capabilities of the actor". Gigerenzer's view is relevant to Simon's environmental blade and to the environmental structures in the three cases in this article, "The term environment, here, does not refer to a description of the total physical and biological environment, but only to that part important to an organism, given its needs and goals." The present article directs attention to research that combines reports on the structure of task environments with the use of adaptive toolbox heuristics of actors. The DSA mapping approach here concerns the match between strategy and an environment-the development and understanding of ecological rationality theory. Aspiration adaptation theory is central to this approach. Aspiration adaptation theory models decision making as a multi-goal problem without aggregation of the goals into a complete preference order over all decision alternatives. The three case studies in this article permit the learner to apply propositions in aspiration level rules in reaching a decision. Aspiration adaptation takes the form of a sequence of adjustment steps. An adjustment step shifts the current aspiration level to a neighboring point on an aspiration grid by a change in only one goal variable. An upward adjustment step is an increase and a downward adjustment step is a decrease of a goal variable. Creating and using aspiration adaptation levels is integral to bounded rationality theory. The present article increases understanding and expertise of both aspiration adaptation and bounded rationality theories by providing learner experiences and practice in using propositions in both theories. Practice in ranking CTSs and writing TOP gists from DSA maps serves to clarify and deepen Selten's view, "Clearly, aspiration adaptation must enter the picture as an integrated part of the search for a solution." The body of "direct research" by Mintzberg, Gladwin's ethnographic decision tree modeling, and Huff's work on mapping strategic thought are suggestions on where to look for research that considers both the structure of the environment and the computational capabilities of the actors making decisions in these environments. Such research on bounded rationality permits both further development of theory in how and why decisions are made in real life and the development of learning exercises in the use of heuristics occurring in natural environments. The exercises in the present article encourage learning skills and principles of using fast and frugal heuristics in contexts of their intended use. The exercises respond to Schank's wisdom, "In a deep sense, education isn't about knowledge or getting students to know what has happened. It is about getting them to feel what has happened. This is not easy to do. Education, as it is in schools today, is emotionless. This is a huge problem." The three cases and accompanying set of exercise questions adhere to Schank's view, "Processes are best taught by actually engaging in them, which can often mean, for mental processing, active discussion."