• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5550-5558
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• 2015

Recently, fuel cell with high energy efficiency and low CO2 emission is energetically interconnected with power system. Especially, FCGS(Fuel Cell Generation System) which usually operates at high temperature, is being developed and installed in the form of large scale system. However, it is reported that power system disturbances related to surge, harmonic and EMI have caused several problems such as malfunction of protection device and damage of control device in the large scale FCGS. In order to solve these problems, this paper presents a modeling of operation characteristics of FCGS by PSCAD/EMTDC, ETAP, P-SIM software. And also, this paper proposes countermeasure algorithms to prevent power system disturbances. From the simulation results, it is confirmed that the proposed algorithm is useful method for the stable operation of large scale FCGS.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.345-358
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• 1999

To study the influences of thermal effluents flowing from hot spring on epilithic algal community, seasonal survey was carried out at stream and its watersheds from Seokjeong hot spring in Chollabuk-Do, Korea. Totally 7 points were divided into three regions fur sampling of water and epilithic algae, such as the direct effected, uneffected and the mixed region, respectively. At the discharging points of effluents, a dark-green cyanobacterial mat were remarkably constructed, mainly by two cyanobacteria, Oscillatoria and Phormidium. The mat formation were more obvious at low temperature than any other season, and even result in disappear with downstream and season. Totally, one hundred and fifty-three taxa of epilithic algae were classified with 15 unidentified species. Among the, diatoms occupied 58％ of total species, whereas cyanobacteria was 67% of total biomass, comparatively. In terms of stream direction, relative abundance of cyanobacteria was only limited in the upstream in cold season, and result in this pattern disappeared with season change. Although all physicochemical variables at the discharging points, was very high, compare to other points, they were quickly decreased downstream. Among them, some heavy metals were not detected or below the detection levels at downstream. Nitrate nitrogen increased with downstream, as well as phosphorus and sulfate have a similar trend throughout, while ammonia quickly decreased in the initial period of discharging effluents. This suggest that although the thermal effluent with high temperature and organic compounds could polluted the small study stream, various contributions such as flowing water, intake of uneffected streawater and collaboration of cyanobacterial mat and stream bottom gradually induces a stable water system.

• Applied Microscopy
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• v.29 no.3
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• pp.331-341
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• 1999

Examination of the morphology of red blood cells in the urine has been shown to be a promising adjunct in determining whether hematuria represents glomerular or nonglomerular bleeding. This is due to distortion of RBCs as they Pass across the basement membrane of the glomerular capillaries. It is concluded that is method can greatly help the clinician in distinguishing between glomerular and nonglomerular bleeding in patients with hematuria and channeling such patients toward the most appropriate investigations. We have experimented dysmorphic red blood cells that 5 patients of the hematuria are distorted with irregular outlines and often have small blobs extruding from the red cell membrane. Tried urinary sediments were seen with phase contrast microscope and confirmed scanning electron microscope. There are seen acanthocytes, anulocytes, ghost cells and sphero-echinocytes in dysmorphic erythrocytes. Clinical diagnosis was referred from the result of the biopsy-proven. Scanning electron microscopic findings of the hematuria are good diagnostic tool that disclose in distorted red blood cells from patients with glomerular disorders.

• Journal of Internet Computing and Services
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• v.16 no.2
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• pp.99-107
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• 2015

In this era of smart convergent environment wherein all industries are converged on ICT infrastructure and industries and cultures come together, the information and communication construction business is becoming more important. For the information and communication construction business to continue growing, it is very important to ensure that technical manpower is stably supplied. To date, however, there has been no theoretically methodical analysis of manpower supply and demand in the information and communications construction business. The need for the analysis of manpower supply and demand has become even more important after the government announced the road map for the development of construction business in December 2014 to seek measures to strengthen the human resources capacity based on the mid- to long-term manpower supply and demand analysis. As such, this study developed the manpower supply and demand forecast model for the information and communications construction business and presented the result of manpower supply and demand analysis. The analysis suggested that an overdemand situation would arise since the number of graduates of technical colleges decreased beginning 2007 because of fewer students entering technical colleges and due to the restructuring and reform of departments. In conclusion, it cited the need for the reeducation of existing manpower, continuous upgrading of professional development in the information and communications construction business, and provision of various policy incentives.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.106-117
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• 2012

The proportion of rebar factory manufacturing which has been settled down in Korea recently seems to increase because of their strength such as high decreasing rate of rebar loss and manufacturing accuracy and the external factors such as an increase of downtown projects and a decrease of skilled workers. However, factory manufacturing using straight rebars causes a certain amount of rebar loss and an environmental problem including $CO_2$ emissions. To solve these problems, Bar in coil (BIC) has been introduced; however its application is very rare because it has not been produced so far in Korea and manufacturing machines of BIC are very expensive. Also, although BIC's application is expected to expand due to its strengths, few analysis of its application has been conducted. Therefore in this study, analysis of the BIC's characteristics and the influence to the rebar manufacturing industry are conducted for the advancement of rebar work as a basic research. To achieve this, inquiry on the present condition of rebar manufacturing industry in Korea is implemented. Then, the validation of BIC's applications by aspects of industry and the analysis of stakeholders' economical profit and loss are conducted.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.92-97
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• 2014

Perchlorate ($ClO_4^-$) is an emerging contaminant of soil/groundwater and surface water. $ClO_4^-$ has been shown to inhibit iodide uptake into the thyroid gland and cause a reduction in thyroid hormone production. $ClO_4^-$ is highly soluble and very stable in water. Biodegradation by $ClO_4^-$-reducing bacteria (PRB) is considered the most important factor in natural attenuation of $ClO_4^-$. Rivers in an industrial complex have potential to be contaminated with $ClO_4^-$ discharged from point or non-point sources. In this study, water samples were taken from the rivers running through the Gumi industrial complexes and used for batch test to analyze $ClO_4^-$-degradation potential of river microorganisms. The results of 83-h batch culture showed that $ClO_4^-$-removal efficiency of all samples was 0.77% or less without addition of an external electron ($e^-$) donor. However $ClO_4^-$-removal efficiency was higher when an $e^-$ donor (acetate, thiosulfate, $S^0$, or $F^0$) was added into the batch culture, showing up to 100% removal efficiency. The removal efficiency was various depending on type of $e^-$ donor and site of sampling. When acetate was used as an $e^-$ donor, the highest $ClO_4^-$-removal efficiency was observed among the $e^-$ donors used in this study, suggesting that activity of heterotrophic PRB was dominant. The results of this study provide basic information on natural attenuation of $ClO_4^-$ by river microorganisms. The information can be useful to prepare a strategy to enhance efficiency of $ClO_4^-$ biodegradation for in situ bioremediation.

• Environmental and Resource Economics Review
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• v.26 no.4
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• pp.577-612
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• 2017

In response to climate change, Korea is attempting to shift the paradigm of energy and climate change policies by introducing carbon pricing based on market mechanisms. While policy adoption is proceeding at a rapid pace, the introduction of carbon pricing has been faced with great opposition from industry. This study measures to what extent Korean companies understand and accept carbon pricing, using data from a questionnaire survey covering energy consuming companies in 2012, when discussions between the government and such companies about the introduction of a domestic emission trading system were active. It further identifies how preparations and practices for carbon and energy management of companies correlate with their policy understanding and acceptance. The analysis results show that the surveyed companies indicate moderate understanding of, as well as resistance to carbon pricing policies, while appreciating the economic incentives and accepting the mandatory regulations in this phase. Companies' understanding is more related to characteristics, i.e., sector, size, etc. than external pressures. This study found that the extent to which companies understand policy is the essential factor in their policy acceptance and related practices. In particular, understanding of carbon policy significantly influences their managerial practices and voluntary activities for carbon and energy practices. This study substantiates the correlation between the level of policy understanding of a company and its carbon and energy practices - something that all countries seeking to introduce carbon pricing in response to climate change should consider prior to policy actually being implemented; in other words, enhancing the understanding of major policy subjects of the new instrument is a key policy strategy that should be elaborated as it will lead to better performance of companies and smoother policy implementation.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1994.05a
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• pp.51-53
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• 1994

담수는 인간의 생존에 필수적인 요소이다. 우리는 매일 일정량의 물을 섭취하고 있으며, 일상에서 직접, 간접적으로 물과 관련되지 않고서는 생활할 수 없다. 지구 표면의 약 70%가 물로서 덮여 있다고는 하지만 인간의 생활에 직접적인 이용가치가 있는 담수(지표수)는 전체 물의 용적의 2%에 지나지 않는다. 한국의 연평균 강수량은 1,274mm로서 세계 연평균 강수량인 970mm보다 많은 편이나 인구 1인당 연간 강수량은 약 3,000m3으로서 세계 평균인 34,000m3의 11분의 1에 지나지 않는다. 수자원총량중 지하침투와 증발에 의해 손실되는 양을 제외한 하천유출량은 전체의 55%인 697억m3으로서 이것이 곧 가용수자원량이다. 그러나 하절기 강우집중도가 높은 우리나라 실정에서는 가용수자뭔량중 수자원총량의 37%가 홍수시 유출되고 실제 이용량은 수자원총량의 18%인 230억m3에 불과하여 인구증가와 함께 수자원의 가치가 더욱 증대하고 있는 실정이다. 더우기 지하수 이용량은 19억m3에 불과함에 따라 우리나라는 실제 이응수자 원량의 90% 이상을 지표수에 의존하고 있으며, 그 중 약 40%가 호소수로 구성되어 있다. 이러한 수자원 이용효율의 취약성으로 인해 제한된 수자원 용량과 생활 및 농공용수의 과수요에 따른 불균형으로 근래 많은 하천이 갈수기나 평수기시 친천화되어 가고 있어 수중생태계에 큰 위협을 주고 있다. 또한 이에 더하여 산업발달과 함께 수질오염원은 양적으로는 물론 질적으로도 증가일로에 있어 기존의 유기 및 중금속 오염물질을 포함해 수많은 신생 유기화합물질이 수계에 유출되고 있으며, 이에 더해 질소 및 인으로 대표되는 영양물질의 유입과다로 국내 대다수의 호수가 부영양화의 새로운 위협에 직 면해 있다. 우리나라에는 적은 유입유량에 큰 저수용량 및 긴 체류시간으로 대표되는 대규모 자연호는 없으며, 대부분이 매단위 강을 막아 형성된 체류시간 1년 이하의 인공호로서 그 중 안동호, 충주호, 대청호 등은 비교적 체류시간이 긴 호소형 인공호로, 팔당호나 기타 대부분의 호수는 체류시간이 짧은 하천형 인공호로 대별된다(Table 1). 이처럼 국내 호소는 국외의 자연 호와는 다른 구조적 특성을 가짐에 따라 부영양화 특성 역시 매우 상이하고, 호소형 인공호와 하천형 인공호간의 차이 역시 현저하여 일률적인 관리대책을 설정하기가 어려운 실정에 있다. 또한 각 호수의 유역특성이 상이함에 따라 호수별로 유역 오염원의 오염부하율이 현저히 달라(Table 2) 호수에 따른 특성적인 유역관리(Lake-specific management)가 요구되고 있다 정상상태(Steady state)가 아닌 국내 호소에 대해 국외 자연호의 인단순모델 (Simple phosphorus budget model)을 그대로 적용하는 것에 다소 무리한 점이 따르나, 평균적인 개념으로 OECD의 유역부하량 및 호소특성에 따른 부영양화 판정모델을 적용한다면, 국내 주요 호수는 모두 부영양 수준에 있다. 또 각 호수별로 부영양화 제어를 위해 요구되는 인의 삭감부하량은 상당량이 되어 현실적으로 관리가 이미 어려운 실정에 와 있다. 호수의 부영양화는 조류 발생으로 이어지며, 그에 따른 폐해는 각종 형태로 나타나는데 대표적으로 이취미 발생이나 유해조류에 의한 독성물질의 배출, 정수처리 과정의 THM 발생등이 주로 문제가 되고 있다. 따라서 국내 호수의 구조적 특성별 부영양화 실태를 파악하고 그에 따른 영향 및 관리방안에 관한 종합적 고찰이 차후 수질관리를 위해 요구되고 있으며, 특히 납조류로 대표되는 유해조류의 독성영향에 관한 연구는 시급한 실정에 있다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.199-206
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• 2001

Behavior of nutrients along the salinity gradients in the Seomjin River estuary was investigated in March July, September and November, 1999. Sampling sites were set based on the surface salinity during each cruise rather than geographic locations. The results suggest that source of nitrate and silicate was the Seomjin River discharge, while that of nitrite and phosphate was waste disposal from the Gwangynng Bay near the mouth of Seomjin River estuary. Ammonia was supplied inside the estuary at the region about $6\~8$ km far from Nancho Island. Strong removal behavior of some nutrient such as ammonia, phosphate and silicate was observed at $5\~15$ psu salinity area in November, where high concentrations of $chlorophyll\;a\;(>8{\mu}g/L$) occurred. High N : P ratios and entirely removal of phosphate at chlorophyll a peak region suggest that phosphate is the limiting factor for phytoplankton growth. Relatively high ratios of Rb to Ra (Rb: Fluorescence before acidification, Ra: Fluorescence after acidification) at $5\~15$ psu salinity region in November indicate that phytoplankton were in good physiological condition.

• Korean Business Review
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• v.18 no.1
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• pp.59-79
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• 2005

recently, world is progressing large quantity consumption with continuous Innovation and economic growth and pollution is accelerated at these process. Increase of industry activity and service that is point of corporation activity is discharging environmental pollutants at whole process to manufacture of end product and exhaust process from acquisition of raw material for accompanied product production hereupon. At the same time, being promoting resources consumption by that use much raw material, As a result, is becoming obstacle factors in sustainable development. So, corporation's responsibility for environmental protection is emphasized. Corporation which must prepare in green round or environmental problems should consider environmental effects that is happened over whole life of products that include waste treatment after raw material acquisition and use as well as selling end product simply. A Life Cycle Assessment techniques is normalized and standardized in International Standard Organization for technical committee 207(TC 207) world widely, and effort to apply in corporation's activity because mastering LCA techniques in domestic several corporations is undergone actively. Coming into effect of Kyoto's Protocol and International Organization for Standard 14000 series revision are presenting new survival principle in competition between country or corporation. LCA technique may become very useful means to corporation which wish to attempt environment management in real condition that awareness for environment is important. Also, An LCA to each product is going to cause big effects in corporation's whole image as well as competitive power raising for single product. Therefore, this research wishes to examine some instances for the future competitive product development at the estimation of environmental friendliness using LCA techniques and more theoretical considerations of the LCA techniques that can dominate corporation's fate.