• 적정기술학회지
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• 제5권1호
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• pp.18-24
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• 2019

인도네시아 반둥인근에서 발원하여 수도인 자카르타인근 해역으로 연결되는 찌따룸강(Citarum river)은 공업 용수와 먹는 물로서 인근 산업 지역과 수도 자카르타의 주요 수자원(공업용수 및 음용수)으로 이용되고 있다. 그러나, 최근 찌따룸강은 처리되지 않은 생활하수 및 섬유산업 폐수로 심각하게 오염되고 있으며, 건기에는 무분별한 지하수 개발로 인해 지하수위가 급속히 하강하는 문제가 발생하고 있다. 따라서, 본 사업에서는 반둥 인근의 섬유공장에서 발생하는 폐수를 재이용하여, 찌따룸강 오염문제와 지하수위 하강문제를 해결하고자 하였다. 이를 위해 수처리용 가압부상장치(DAF)를 개량한 공법인 선회식 가압부상장치(CYFLOAT) 시스템을 인도네시아 현장에 맞게 개선하여 100 톤/일 용량 규모로 설치 및 운전하였다. 설치한 선회식 가압부상장치 시스템은 섬유 폐수 재이용 시 가장 중요한 수질기준 중 하나인 부유물질(SS)을 약 40분의 체류 시간 동안 96.8% 제거하였을 뿐만 아니라, 공간사용 및 유지관리측면에서도 매우 유리한 것으로 확인되었다. 또한, 본 기술의 설치와 운영에 현지 관련기관들(UNPAR 및 ITB, PU SKIM)을 참여시켜, 해당 기술이 인도네시아 찌따룸강 유역의 섬유공장 밀집지역내 지속적으로 적용 가능하도록 하였다.

• Parasites, Hosts and Diseases
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• 제48권2호
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• pp.105-111
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• 2010

To understand the situation of water contamination with Cryptosporidium spp. and Giardia spp. in the northern region of Portugal, we have established a long-term program aimed at pinpointing the sources of surface water and environmental contamination, working with the water-supply industry. Here, we describe the results obtained with raw water samples collected in rivers of the 5 hydrographical basins. A total of 283 samples were analyzed using the Method 1623 EPA, USA. Genetic characterization was performed by PCR and sequencing of genes 18S rRNA of Cryptosporidium spp. and $\beta$-giardin of Giardia spp. Infectious stages of the protozoa were detected in 72.8% (206 of 283) of the water samples, with 15.2% (43 of 283) positive for Giardia duodenalis cysts, 9.5% (27 of 283) positive for Cryptosporidium spp. oocysts, and 48.1% (136 of 283) samples positive for both parasites. The most common zoonotic species found were G. duodenalis assemblages A-I, A-II, B, and E genotypes, and Cryptosporidium parvum, Cryptosporidium andersoni, Cryptosporidium hominis, and Cryptosporidium muris. These results suggest that cryptosporidiosis and giardiasis are important public health issues in northern Portugal. To the authors' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in raw water samples in the northern region of Portugal.

• 한국컴퓨터산업학회논문지
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• 제2권8호
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• pp.1055-1062
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• 2001

본 연구에서는 1KHz 부근의 펄스 반복율을 가지는 경제적이고 컴팩트한 펄스형 $CO_2$ 레이저의 개발에 관해서 기술하였다. 고압 고주파 펄스 변압기와 수 십 KHz의 스위칭에 적합한 IGBT를 사용한 고압 펄스전원 장치를 레이저 공진기에 접목시켜 새로운 방식의 고반복 $CO_2$ 레이저 장치를 개발하였다. 전원장치에 사용된 2개의 IGBT를 정밀하게 제어하기 위해서 제어부에는 PIC 마이크로프로세서가 사용되었고 공진기는 수냉방식의 저속축류형으로 제작되었다. 완성된 장치의 펄스 반복율과 동작압력 그리고 레이저 매질 가스의 혼합비의 변화에 따른 레이저빔의 출력 특성실험을 통하여 가스 배압비 $CO_2$： $N_2$：He ＝ 1：9：15펄스 반복율 700 Hz, 동작압력 15 Torr에서 최대 레이저 출력 약 20.5 W, 최대 효율 약 8%를 달성하였다.

• 한국시스템다이내믹스연구
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• 제4권2호
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• pp.71-94
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• 2003

The purpose of this dissertation is to build a development density control model and estimate optimum developmental density level for a sustainable urban growth management. To develop the model, system dynamics modeling approach was used. The model was developed to analyze how urban growth, transition, and decay occur depending on the interaction among population, houses, industry structure, land and urban infrastructure such as road, water supply, and sewage treatment facilities. The model was applied to Anyang city to estimate optimum density level. Extensive computer simulation was conducted to find out the maximum numbers of population, industry structure, houses, and cars that can be adequately sustained with the current Anyang city's infrastructure capacity. The computer simulation result shows that the city is overpopulated by some 90,000 people. It nab analyzed that 20％ increase of existing capacity of urban infrastructure is necessary to support current population of Anyang city. To reduce the population to the adequate level whereby the current urban infrastructure can sustain, the current city regulation on floor area ratio needs be strengthened at least 20％ to 35%.

• 한국축산시설환경학회지
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• 제21권2호
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• pp.47-54
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• 2015

Climate change has directly impacted environmentally dependent first industry. The changes of amount and frequency of precipitation have caused unstable drinking water supply for grassland and feed crop, and have changed the variety of grassland and feed crop. Rising temperature has caused heat stress on livestock, which has impacted feed intake and livestock products, and also has threatened to the health of livestock by widening the range of sources of diseases. In order for livestock industry to confront climate change, new technology development for climate change adaptation and measures of greenhouse gas mitigation are essential. Agroforestry is the one of alternative measures to mitigate greenhouse gases and to adapt to climate change. Agroforestry is the way rearing livestock and cultivating plants in forest, which is suitable to Korea where mountain area is over 68%. Feedstock such as maize, soybean, rice, and grass grown by agroforestry would decrease feed cost. Agroforestry will decrease heat stress of livestock during hot weather and will be possible to pasture, which increases livestock welfare.

• 한국축산식품학회지
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• 제39권4호
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• pp.521-540
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• 2019

This review summarizes the current trends related to insect as food resources among consumers, industry, and academia. In Western societies, edible insects have a greater potential as animal feed than as human food because of cultural biases associated with harmful insects, although the abundant characteristics of edible insects should benefit human health. Nevertheless, many countries in Asia, Oceania, Africa, and Latin America utilize insects as a major protein source. Using insects can potentially solve problems related to the conventional food-supply chain, including global water, land, and energy deficits. Academic, industry, and government-led efforts have attempted to reduce negative perceptions of insects through developing palatable processing methods, as well as providing descriptions of health benefits and explaining the necessity of reducing reliance on other food sources. Our overview reveals that entomophagy is experiencing a steady increase worldwide, despite its unfamiliarity to the consumers influenced by Western eating habits.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.15-18
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• 2003

Development of the construction industry generally exhausts natural aggregate. Hence it is problem to the lack of supply and quality deterioration, so the resource saving and protection of environment is made an effort through recycling by-product. This study presents that fundamental properties of concrete which used cooper slag as alternate sand of low fineness modulus and plan of cooper slag as concrete aggregate. Testing factors are concrete's slump, air contents, unit weight and compressive strength. The results of this study are as follows; (1) Concrete slump is generally satisfied with the condition but is inferior to the others in substitution rates 30%. Also air contents are 3.1-4.1% and go up according to increase substitution rate. (2) Unit weight increase in 1.1% as the mixing ratio of cooper slag argument 10%. (3) compressive strength of cooper slag concrete is similar to plain and especially higher 11-15% in W/C 45%, 50%. So it seems that aggregate mixed cooper slag is suitable to low water-cement ratio mixture.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.224-225
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• 2005

The lightness of components required on marine and shipbuilding industry is requiring high strength of components. In particular, fatigue failure phenomena, which happen in metal, bring on danger in human life and property. Therefore, antifatigue failure technology takes an important part of current industries. In this study, it was investigated about endurance and fatigue crack propagation rate of according to stress ratio of SMAW commonly using for welding structures in present. Fatigue crack propagation rate(da/dN) of low load(R=0.1) was lower than of high load(R=0.6) for piping weld. And in stage I, ${\Delta}$Kth, the threshold stress intensity factor of the weld under heavy load is higher than under small load. Fatigue life shows more improvement in the weld of stress ratio R=0.l than in the weld of stress ratio R=0.6.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.346-348
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• 2007

Underground pipe is an instrument to transport rapidly and safely a lot of fluid like gas, oil, water supply and drain system. It acts like blood vessels of human body in a modern industry. As in this country, the pipe facilities have been constructing since 1970's. The pipes constructed for a long time ago are already starting to reveal the problem like corrosion and most of them are built underground. So for companies, the managing of the underground pipes is very hard because it needs high technology and a lot of money. So we made a new robot system to repair and maintain the pipes at a low price. This new robot is devised using pressing wall type to work inside 700${\sim}$900(mm) size pipe. And it has good carrying and working power.

• 기술사
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• 제43권3호
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• pp.28-33
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• 2010

The related industrial technologies are also being developed in medicine, education, the military, transportation, process management, security management and information technology industries due to a rapid progress in telecommunications technology. The supervisory remote control system is based upon telecommunications technology. The supervisory remote control systems are used in various ways such as city gas, water supply and drainage, environment, power, communication and device control fields. The supervisory remort control system became a solution with complex systems and important technologies in electricity, city gas filed that require safety management skills. The supervisory remote control system as a special technology has a lot of practical applications. In this paper, Let me examine the present status of remort control system applications and present development plans and alternatives in city-gas industrial technology.