• 신재생에너지
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• 제4권2호
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• pp.21-30
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• 2008

Anaerobic digestion (AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.231-237
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• 2007

To monitor process of vegetation rehabilitation at the damaged area after large-fire is required a lot of manpowers and budgets. However the analysis of vegetation recovery using satellite imagery can be obtaining rapid and objective result remotely in the large damaged area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. Burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. To classify fire damaged area and analyze burn severity of Samcheok fire area occurred in 2000, Cheongyang fire 2002, and Yangyang fire 2005 was utilized Landsat TM and ETM+ imagery. Therefore the objective of the present paper is to quantitatively classify fire damaged area and analyze burn severity using normalized burn index(NBR) of pre- and post-fire's Landsat satellite imagery.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.202-205
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• 2008

Anaerobic digestion(AD) is the most promising method of treating and recycling of different organic wastes, such as OFMSW, household wastes, animal manure, agro-industrial wastes, industrial organic wastes and sewage sludge. During AD, i.e. degradation in the absence of oxygen, organic material is decomposed by anaerobes forming degestates such as an excellent fertilizer and biogas, a mixture of carbon dioxide and methane. AD has been one of the leading technologies that can make a large contribution to producing renewable energy and to reducing $CO_2$ and other GHG emission, it is becoming a key method for both waste treatment and recovery of a renewable fuel and other valuable co-products. A classification of the basic AD technologies for the production of biogas can be made according to the dry matter of biowaste and digestion temperature, which divide the AD process in wet and dry, mesophilic and thermophilic. The biogas produced from AD plant can be utilized as an alternative energy source, for lighting and cooking in case of small-scale, for CHP and vehicle fuel or fuel in industrials in case of large-scale. This paper provides an overview of the status of biogas production and utilization technologies.

• Geomechanics and Engineering
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• 제8권5호
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• pp.675-685
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• 2015

Weathering is the breaking/cutting down process of rocks due to physical and chemical processes in natural as well as artificial environment including $CO_2$ injection for storage in the sediment, or natural resource recovery process. This study suggests an alternative method to estimate the degree of weathering for granites. A series of laboratory and field experiments are performed to measure electrical resistivities on various rock samples experienced different degrees of weathering and their residual soils under different saturation conditions. It is found that the normalized electrical resistivity increases with a decrease in water absorption and the saturation. Simple boundaries are suggested to identify the weathering degree of granites, based on limited data. Field test results for three sites confirm that the suggested method could be estimated well the degree of weathering of granites compared with the other methods suggested previously. Although further research is required, this study suggests that an electrical resistivity could be an effective approach to estimate the degree of weathering of granites compared with the other methods suggested previously.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.693-698
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• 2001

This paper establishes a coding method system including the liberation and size distribution of recycling materials in the shredder operation. Every particle in the shredded product becomes a code number using the liberation model and size distribution equation transforming of weight percentage into particles number percentage. One set of database can be obtained after all particles have been coded. This database is suitable for the size reduction operation in the process simulation of waste recycling. Coupling with the developed air classification, sizing and separating operations, the whole process simulation will be completely established for diversified application. A typical simulation for the rolling cutting shredder product of waste TV had been demonstrated under this coding system. The breakage size distribution of Gaudin and Schumann equation were selected for the shredding operation simulation. The Gaudin's liberation model was suitable fur the liberation simulation. Both of these equations were transformed weight percentage into particles distribution for the necessary of particle coding method. A better recycling operation for this shredded solid waste can be concluded from the comparison of simulation results with their sorted grade, recovery or economic of materials in different processes.

• Nuclear Engineering and Technology
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• 제47권4호
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• pp.443-453
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• 2015

A hybrid safety injection tank (H-SIT) can enhance the capability of an advanced power reactor plus (APR+) during a station black out (SBO) that is accompanied by a severe accident. It may a useful alternative to an electric motor. The operations strategy of the H-SIT has to be investigated to achieve maximum utilization of its function. In this study, the master logic diagram (i.e., an analysis for identifying the differences between an H-SIT and a safety injection pump) and an accident case classification were used to determine the parameters of the H-SIT operation. The conditions that require the use of an H-SIT were determined using a decision-making process. The proper timing for using an H-SIT was also analyzed by using the Multi-dimensional Analysis of Reactor Safety (MARS) 1.3 code (Korea Atomic Energy Research Institute, Daejeon, South Korea). The operation strategy analysis indicates that a H-SIT can mitigate five types of failure: (1) failure of the safety injection pump, (2) failure of the passive auxiliary feedwater system, (3) failure of the depressurization system, (4) failure of the shutdown cooling pump (SCP), and (5) failure of the recirculation system. The results of the MARS code demonstrate that the time allowed for recovery can be extended when using an H-SIT, compared with the same situation in which an H-SIT is not used. Based on the results, the use of an H-SIT is recommended, especially after the pilot-operated safety relief valve (POSRV) is opened.

• Nuclear Engineering and Technology
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• 제45권6호
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• pp.795-802
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• 2013

For the improvement of APR1400 Diverse Protection System (DPS) design, the Advanced DPS (ADPS) has recently been developed to enhance the fault tolerance capability of the system. Major fault masking features of the ADPS compared with the APR1400 DPS are the changes to the channel configuration and reactor trip actuation equipment. To minimize the fault occurrences within the ADPS, and to mitigate the consequences of common-cause failures (CCF) within the safety I&C systems, several fault avoidance design features have been applied in the ADPS. The fault avoidance design features include the changes to the system software classification, communication methods, equipment platform, MMI equipment, etc. In addition, the fault detection, location, containment, and recovery processes have been incorporated in the ADPS design. Therefore, it is expected that the ADPS can provide an enhanced fault tolerance capability against the possible faults within the system and its input/output equipment, and the CCF of safety systems.

• Journal of Chest Surgery
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• 제26권2호
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• pp.129-134
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• 1993

We compared postoperative results according to the different surgical approach in 180 cases of isolated ventricular septal defects operated at the department of Thoracic and Cardiovascular Surgery in Kyungpook University Hospital from January 1987 to December 1991. Of the 180 cases, 109 were males and 71 females, age ranging from 6 months to 15 years (mean: 5.6 years) and body weight ranging from 6 to 52㎏(mean : 20㎏). According to Soto's classification, perimembranous types were comprised of 119 cases (66％), doubly committed subarterial type 49 cases(27％), and muscular type 12 cases(7％). Patients were divided into three groups according to the incision methods: right atriotomy group (39％), right ventriculotomy group (47％), and pulmonary arteriotomy group (14％). The mean aortic cross clamp time was shorter in right atriotomy group (39 min.) than right ventriculotomy group (79min.) in the cases of large perimembranous VSD (P＜0.001). Spontanous recovery rate of cardiac rhythm after VSD closure was higher in right atriotomy group (51％) than right ventriculotomy group (32％) in the cases of perimembranous VSD (P＜0.05). The incidence of postoperative RBBB was 17.6％ with no statistical differences between right atriotomy group(17.9％) and right ventriculotomy group(19.2％). Overall mortality rate was 5.6％(10 cases) with no significant differences according to surgical approach.

• Clinical and Experimental Pediatrics
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• 제50권4호
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• pp.323-327
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• 2007

Although most clinicians now agree that sinusitis can afflict children of all ages, appropriate diagnosis remain controversial. Sinusitis is one of the most challenging diagnoses for a clinician, because there is a lack of validated diagnostic criteria for acute rhinosinusitis. Symptoms generally include nasal congestion, purulent nasal discharge, and cough .The physical examination is often unsuccessful in confirming the diagnosis. If purulent discharge is seen oozing from the middle meatus, the diagnosis of acute rhinosinusitis is almost certain. Purulent drainage may also be seen in the posterior pharynx and accompanied by halitosis. Absence of light by transillumination may indicate acute rhinosinusitis. Imaging studies are not necessary to confirm the diagnosis of sinusitis in children younger than 6 years and should be used sparingly in children older than 6 years. Sinus radiographs still have several advantages over CT scanning including the relatively low cost and the ability to obtain films without the use of sedation in younger children. Positive findings of sinusitis on plain film include air-fluid levels, complete opacification, or mucosal thickening greater then 4 mm. The CT scan however, is significantly more sensitive then plain films in detecting these abnormalities. Although recovery of bacteria from a sinus aspiration is considered reference standard for diagnosis in pediatric rhinosinusitis, its routine used by pediatricians is not practical and therefore is not recommended.

• 자원리싸이클링
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• 제16권6호
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• pp.34-38
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• 2007

폐콘덴서로부터 탄탈륨 음극을 회수하기 위하여 물리적 선별과, 염소가스와 사염화탄소를 이용한 기초 염화반응에 관한 연구를 수행하였다. Stamp mill을 이용한 파쇄, 요동테이블에서의 습식 비중선별 그리고 공기 분급을 통하여 탄탈륨 음극을 98% 회수할 수 있었다. 염소가스를 이용한 TGA분석에서 탄탈륨 음극의 최대 무게 감소는 60%였고, 사염화탄소에 의한 탄탈륨 음극의 염화반응은 탄탈륨 음극을 산화탄탈륨으로 변환한 후가 반응율이 높았다.