• Journal of Digital Convergence
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• v.15 no.5
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• pp.37-48
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• 2017

Recently, the importance of software education is growing because computational thinking of software education is recognized as a key means of future economic development. Also human resources who will lead the 4th industrial revolution need convergence and creativity, computational thinking based on critical thinking, communication, and collaborative learning is known to be effective in creativity education. Software education is also a time needed to reflect social issues such as collaboration with developers sharing interests and open source development methods. Github is a leading social coding site that facilitates collaborative work among developers and supports community activities in open software development. In this study, we apply operational cases of basic learning of social coding sites, learning for storage server with sources and outputs of lectures, and open collaborative learning by using Github. And we propose educational model consisted of four stages: Introduction to Github, Using Repository, Applying Social Coding, Making personal portfolio and Assessment. The proposal of this paper is very effective for software education by attracting interest and leading to pride in the student.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.22-31
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• 2008

Recently, with the develop of the location tracking technology using GPS and mobile device such as PDA and UMPC, it is used in various application fields that is coordinate transformation and compensation using GPS, is client development for Mobile GIS using GIS and is development of surface survey system for archaeological site based on mobile. In this paper, we develop the system that can investigate the growth information and production information of rice in crop of the field using mobile device, show position information of user and rice in digital map using GIS and save the investigated crop information and position information in database in server. The system which is developed in this paper consists of modules that the user management module is able to restrict database approaches in authority by of the user, the crops management module is able to save and search crop information in database in server, the map module is able to show position information of user and crops in digital map, the location information module is able to convert received location information from GPS and the communication module is able to send and receive data between GPS and mobile device and between mobile device and database. Finally, this paper shall contribute to efficient management and investigation of birth information of crop in field.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.210-217
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• 2015

Fluoride removal by acid and heat treated red mud were studied in batch and column system regarding contact time, initial concentration, pH, adsorbent dose, and filter depth. The results showed that acid treated with 0.8 M HCl, had highest adsorption capacity of fluoride and adsorption capacity decreased as heat treatment temperature increased. Sorption equilibrium reached in 30 min at a initial concentration of 50 mg-F/L but 1 h was required to reach the sorption equilibrium at the initial concentration of 500 mg-F/L by 0.8 M acid treated red mud (0.8 M-ATRM). Equilibrium adsorption data were fitted well to Langmuir isotherm model with maximum fluoride adsorption capacity of 23.162 mg/g. The fluoride adsorption decreased as pH increased due to the fluoride competition for favorable adsorption site with $OH^-$ at higher pH. Removal percentage was increased but the amount of adsorption per unit mass decreased by adding the amount of 0.8 M-ATRM. It was concluded that the 0.8 M-ATRM could be used as a potential adsorbent for the fluoride removal from aqueous solutions because of its high fluoride adsorption capacity and low cost.

• The Journal of Engineering Geology
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• v.23 no.3
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• pp.227-234
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• 2013

The vertical shaft of a selective intake structure, which is constructed in a large reservoir, is required to be impermeable and to employ a grouting technology to prevent water inflow from the reservoir or surrounding ground. In this study, groundwater inflow is estimated using a numerical model for two cases (i.e., grouting or non-grouting cases at the exterior of a vertical shaft) and compared with data measured during an excavation at the construction site of a selective intake structure in the Soyang reservoir, Korea. Groundwater inflow is estimated to range from 444 to 754 $m^3/d$ in the case of non-grouting and from 58 to 95 $m^3/d$ in the case of grouting. The groundwater inflow measured in a vertical shaft, which ranges from 30 to 100 $m^3/d$, is similar to the simulated amount. It is recommended that before the excavation of a shaft, water inflow is estimated using a numerical model and a grouting test to ensure excavation stability and improve excavation efficiency.

• The Journal of Engineering Geology
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• v.23 no.3
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• pp.283-292
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• 2013

A calcareous rock slope failed during excavation of the slope for construction of a tunnel entrance. The slope is located at the construction site for widening highway in Yeongwol, Korea. Field surveys, laboratory tests, and numerical analyses were performed to determine the reason for the slope failure. The numerical analysis revealed that the safety factor of the slope before construction of the entrance was less than 1, and that this decreased after construction. After construction of the entrance, the sliding zone of the slope increased and slope stability decreased because the shear strain and plastic zone in the slope over the tunnel entrance showed an increase relative to the lower part of the slope. To enhance the stability of the slope for construction of the tunnel entrance, countermeasures such as rock bolts, rock anchors, and FRP (Fiber glass Reinforced Plastic) grouting were adopted in light of the field conditions. Serial field monitoring performed to confirm the reinforcing effects of the adopted countermeasures revealed a small amount of horizontal deformation of the slope soils, most of the elastic deformation that can regain its former value. In addition, the axial forces of the rock bolt and anchor were more strongly affected by slope excavation during construction of the tunnel entrance than by tunnel excavation or the rainy season, and the axial forces tended to converge after excavation of the tunnel. Therefore, we can confirm that the slope is currently safe.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.244-250
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• 2000

Algal growth potential (AGP) bioassay were conducted to assess the water quality and fertility in the Kum River from March 1998 to June 1999. AGP values were always the highest at the conjuction site of the Kapchon, which is a tributary of the Kum River. Average value of AGP by Microcystis aeruginosa in the main river and tributary was 17.0 mg dw/l, 48.3 mg dw/l, respectively. AGP values decreased towards the lower part of the river and consisted in the water quality or nutrient analysisresults. Among the tributaries, AGP of the Kapchon, Mihochon and Soksongchon were relatively high, and the average value was 161.2, 50.3 and 125.6 mg dw/l, respectively. AGP value in the Yukuchon was lowest among the study stations with <2.7 mg dw/l. Water quality in the lower part of the Kum River deteriorated in drought season, and the AGP values of this season were higher than those in other seasons. Based on correlation analysis between AGP results and nutrients, limiting nutrient appeared to be P because SRP (r = 0.99) was higher than other nutrients, and N uptake in algal growth was preferred by $NH_4$ rather than $NO_3$. The variation of AGP was different according to localities and seasons, and it was related to nutrient fluctuation in the inlet tributary. Water quality status according to AGP was assessed to be eutrophic.

• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.373-384
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• 2011

The objective of this was to determine how the seasonal intensive rainfall influenced the water quality, and to analyze the long-term temporal trend of water chemistry and spatial heterogeneity in the upstream watershed of Southern Han River using water quality dataset from 1997 to 2007. The largest seasonal variability in most parameters occurred during the two month July and August and there were closely associated with a large spate of summer monsoon rain. Total phosphorus (TP), chemical oxygen demand (COD), and suspended solids (SS) were greater during summer than any other seasons, and had a direct correlation with precipitation (r>0.4, p<0.01, n-120). In addition, dissolved oxygen (DO) had and inverse function with precipitation (r=-0.542, p<0.01). Overall, the data of total phosphorus (TP) and suspended solids (SS) showed that water quality was worst in Site I1, compared to the others. This was due to continuous effluents from the highlands' fields and cattle farms within the upstream area of Doam lake (Song stream). Based on the overall dataset, an efficient water quality management is required in the highlands and farms areas for better water quality with precipitation (r.0.4, p<0.01, n=120).

• Fire Science and Engineering
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• v.28 no.1
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• pp.71-78
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• 2014

Complex ethical issues of Emergency Medical Techinician (EMT) out-of hospital emergency medical scene and the ER (Emergency Room) behaviors were studied. The survey was conducted by 500 EMT group members working in the field of ambulance work and general hospital and it was about their work ethics, discussions and solutions about the transferred patients, and ethics regarding Do Not Attempt Resuscitate (DNAR). The survey includes work ethics, awareness about the target job, a discussion on the transfer of patients, measures, and deathbed. Discussions about the patient's condition and diagnosis results were majorly absent during patient transportation at the emergency care scene. More than 90% of emergency care transfer were inappropriate. Sometimes, EMT working in the field facing morally unethical problems beyond their responsibility. When EMT, who can not make death diagnosis, received deathbed related DNAR issues, they gone through severe ethical conflicts. The institutional support and therapy for EMT was weak. In Korea, especially in the accident site, ethical issues education is more needed than DNAR prevalence of education and guidance. If ethics training and guidance are given to EMT, a lot of moral errors in the field can be resolved.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.241-245
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• 2007

국내 홍수빈도 분포의 매개변수 추정에서 지점추정(at-site estimate) 방법은 유량 자료의 부족으로 발생하는 표본오차(sampling error)가 크기 때문에 충분한 유량 자료를 보유한 지점에 한하여 제한적으로 사용되고 있다. 대안으로 동질성을 가진 유역의 유량 자료를 모아 지역 매개변수를 추정하는 지수홍수법(Index Flood Method)이 제안되기도 하였으나, 이질성이 큰 우리나라의 유역특성 때문에 적용이 쉽지 않다. Stedinger와 Tasker가 1986년 제안한 GLS(Generalized Least Square) 기법은 유역을 동질지역으로 구분할 필요가 없으며 지점들간의 상관관계와 이분산성을 고려할 수 있어, 국내 홍수빈도 해석을 위해서 꼭 도입해야할 기법으로 생각된다. 본 연구에서는 기존의 GLS 기법의 단점을 보완한 Bayesian-GLS 기법을 이용하여, 국내 대유역에 골고루 위치하며 댐의 영향을 받지 않는 31개 지점의 연최대 일유량 시계열의 L-변동계수(L-moment coefficient variation)와 L-왜도계수(L-moment coefficient skewness)를 추정할 수 있는 회귀모형을 제안하였다. 위 회귀모형을 구성하기 위한 유역특성으로는 유역면적, 유역경사, 유역평균강우 등을 사용하였다. Bayesian-GLS (B-GLS) 적용 결과를 OLS(Ordinary Least Square) 및 Bayesian-GLS 기법에서 지점간의 상관관계를 고려하지 않는 Bayesian-WLS(Weighted Least Square)와 비교 평가하여 그 우수성을 입증하였다. 따라서 본 연구에서 제안된 B-GLS에 의한 지역회귀모형은 국내의 미계측유역이나 또는 관측 길이가 짧은 계측유역의 홍수빈도분석을 위해 매우 유용할 것으로 기대된다.년 홍수 피해가 발생하고 있지만, 다른 한편 인구밀도가 높고 1인당 가용 수자원이 상대적으로 적기 때문에 국지적 물 부족 문제를 경험하고 있다. 최근 국제적으로도 농업용수의 물 낭비 최소화와 절약 노력 및 타 분야 물 수요 증대에 대한 대응 능력 제고가 매우 중요한 과제로 부각되고 있다. 2006년 3월 멕시코에서 개최된 제4차 세계 물 포럼에서 국제 강 네트워크는 "세계 물 위기의 주범은 농경지", "농민들은 모든 물 위기 논의에서 핵심"이라고 주장하고, 전 프랑스 총리 미셀 로카르는 "...관개시설에 큰 문제점이 있고 덜 조방적 농업을 하도록 농민들을 설득해야 한다. 이는 전체 농경법을 바꾸는 문제..."(segye.com, 2006. 3. 19)라고 주장하는 등 세계 물 문제 해결을 위해서는 농업용수의 효율적 이용 관리가 중요함을 강조하였다. 본 연구는 이러한 국내외 여건 및 정책 환경 변화에 적극적으로 대처하고 물 분쟁에 따른 갈등해소 전략 수립과 효율적인 물 배분 및 이용을 위한 기초연구로서 농업용수 수리권과 관련된 법 및 제도를 분석하였다.. 삼요소의 시용 시험결과 그 적량은 10a당 질소 10kg, 인산 5kg, 및 가리 6kg 정도였으며 질소는 8kg 이상의 경우에는 분시할수록 비효가 높았으며 특히 벼의 후기 중점시비에 의하여 1수영화수와 결실율의 증대가 크게 이루어졌다. 3. 파종기와 파종량에 관한 시험결과는 공시품종선단의 파종적기는 4월 25일부터 5월 10일경까지 인데 이 기간중 일찍 파종하는 경우에 파종적량은 10a당 약 8${\ell}$이고 늦은 경우에는 12${\ell}$ 정도였다. 여기서 늦게 파종한 경우 감수의 가장 큰 원인은 1수영화수가 적어지기 때문이었다. 4. 건답직파에 대한 담수상태로 관수를 시작하는 적기는 파종후

• Journal of Korea Water Resources Association
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• v.48 no.12
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• pp.1051-1064
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• 2015

Currently, the H purification plant determines the hourly water intake amount based on operator experience and skill. Therefore, inevitably, there are deviations among operators. While meeting time-varying demand and maintaining the proper water level in the clean water reservoir, the methodology for minimizing electricity cost, when dealing with different electricity rate time zones, is a very complicated problem, which is beyond an operator's capability. To solve this problem, a linear programming (LP) model is proposed, which can determine the optimal hourly water intake amount for minimizing the daily electricity cost. It is shown that an inaccurate estimate for the hourly water usage in the demand areas causes the water level constraint to be violated, which is the weak point of the proposed LP method. However, several examples with real-field data show that we can practically and safely solve this problem with safety margins. It is also shown that the safety margin method still works effectively whether the estimate is accurate or not. The operators need not attend the site at all times under the proposed LP method, and we can additionally expect reductions in labor costs.