• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.264-270
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• 2016

This Study is to into fuel using a torrefation reaction to food waste. When the fuel of only food waste alone, fuel value is was performed at a ratio of sewage sludge constant attempts to prevent low. Mixing ratios of food waste and sewage sludge, 10:0, 8:2, 6:4, 5:5. Regardless mixing ratio, it was possible to confirm that decreases the moisture content of 10% or less at a reaction temperature of $240^{\circ}C$ or higher. As the ratio of the reaction temperature and the sewage sludge is high, the fixed carbon content is increased. It was measured at up to 36%(mixing ratios6:4, reaction temperature $270^{\circ}C$) from the initial 1.1%. From the reaction temperature $240^{\circ}C$ satisfied with 3000Kcal/Kg or more is a SRF criteria shows the calorific value. It was possible to obtain a heating value that is increased from the raw sample approximately sextuple. As reaction temperature is heightened, Van krevelen Diagram moved to the range of Lignite range. It was possible to obtain high fuel ratio and 5,500Kcal/kg or less of a combustility index as the sewage sludge mixing ratio becomes high. Increase the fixed carbon content, than those food waste alone solid fuel into and improved fuel costs, it is necessary to ensure that the quality of the fuel is improved.

• Korean Journal of Soil Science and Fertilizer
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• v.31
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• pp.36-44
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• 1998

우리 나라에서 토양의 점토광물에 관한 최초의 연구는 1958년 김제지방의 답 토양에 관한 연구로 (Dewan, 1958)시작되었다. 1960년대 시작하여 1970년대 까지는 주로 토양점토광물의 동정이 이루어 졌다. 점토광물의 동정(同定)에 사용된 잔적토(殘積土)(Residual Soil)로는 화강암(花崗岩), 화강편마암(花崗片麻岩), 현무암(玄武岩), 석회암(石灰岩), 혈암(頁岩), 제(第)3기층(紀層), 홍적층(洪積層) 유래 토양과 토양종류별(土壤種類別)로는 과부식회색토(寡腐植灰色土), 염류토(鹽類土), 충적토(沖積土), 적황색토(赤黃色土), 화산회토(火山灰土), 퇴적토(堆積土), 갈색토(褐色土), 암쇄토(岩碎土), 저위생산답(低位生産畓)이였으며, 토양점토광물(土壤粘土鑛物)과 작물수량성(作物收量性) 관계에 관한 연구가 실시되었다. 1980년대에 들어와서는 토양중의 1차광물과 점토광물의 풍화에 대한 안정도와 1차광물의 동정이 행해졌으며, 이밖에 Kaolinite 입자의 전하에 관한 연구등 점토광물의 흡착과 활성 연구, 점토광물의 토양개량재로서의 흡착과 화학적 특성 변화 연구와 점토광물의 토양개량 시용효과에 관한 연구가 행해졌다. 1990년대에 들어와서는 토양 중의 1차광물과 점토광물의 정량에 대한 자료가 축척되었고, 토양의 풍화에 대한 안정성과 생성기작, Zeolite와 새로운 광물이 합성되었다. 또한 합성광물을 이용한 농업과 산업광물로의 응용성 환경 산업에서의 적용가능성에 대한 평가가 시도되었다. 토양의 점토광물의 조성에 관한 연구는 토양 모재를 중심으로 이루어졌는데, 화강암(花崗岩)에서는 Halloysite, 화강편마암(花崗片麻岩)에서는 Kaolinite, Metahalloysite, Illite, 산성암(酸性岩)에서는 Kaolinite, Venrmiculite와 Chlorite의 중간광물, 현무암(玄武岩)에서는 Illite, Kaolinite, Vermiculite, 석회암(石灰岩)에서는 Vermiculite-Chlorite 중간광물, Kaolinite와 Illite, 혈암(頁岩)에서는 Kaolinite, Halloysite, Illite 외 Vermiculite-Chlorite, 화산회토(火山灰土)에서는 Allophane이 주광물이었다. Soil Taxonomy와 토양광물과의 관계에서, 답 토양에서는 Entisols의 주점토광물은 2:1형과 1:1형 광물이지만 Inceptisols와 Alfisols에서는 Halloysite가 대부분이다. 밭 토양의 경우는 Alfisols의 주점토광물은 Vermiculite, Illite, Kaolinite이었고, Ultisols에서는 Vermiculite-Chlorite 중간광물이었다. 산림토양에서는 Inceptisols중에서 Andept는 Allophane, Alfisols에서는 2:1 광물이지만, Ultisols에서는 Halloysite이다. 모재별 조암 광물의 풍화와 점토광물의 생성과정에서 화강암(花崗岩)과 화강편마암(花崗片麻岩)의 장석류(長石類)는 kaoline광물로, 이 밖의 운모광물(雲母鑛物), 녹니석(綠泥石), 각섬석(角閃石), 휘석(輝石)으로부터 생성된 illite, chlorite, vermiculite는 풍화중간에 혼층단계(混層段階)를 거쳐서 kaoline 광물로 풍화된다. 석회암(石灰岩) 토양의 smectite가 Mg농도가 높은 토양용액으로부터 침전되어 생성되었거나 운모 또는 chlorite에서 유래된 vermiculite의 변성작용에 의해 생성되고, 혈암(頁岩)토양의 점토에 illite가 주로 풍화에 저항성이 큰 미립자의 함수백운모(含水白雲母)로부터 유래되며, 현무암(玄武岩) 중의 장석류(長石類)는 kaoline광물로, 휘석(輝石)은 chlorite${\rightarrow}$illite의 풍화과정을 거친다. Zeolite, 함불석 Bentonite, Bentonite 등 우량점토 광물이 분포과 광물조성, 이화학적 특성이 조사되었고, 토양의 물리적, 화학적 성질의 개선을 필요로 하는 토양의 개량을 위해서 Bentonite, Zeolite, Vermiculite 등의 토양 개량재(改良材)로서의 기초연구와 이들 개량재 시용효과에 관한 연구 등이 주로 논토양에서 수행되었다. 점토광물과 수량관계를 보면 Montmorillonite를 주점토광물로 함유된 답 토양의 수도수량이 1:1 광물을 주점토광물로 함유하고 있는 토양에서의 수도수량 보다 높았다. 토양광물에 관한 기초연구(基礎硏究)로서 양이온교환능과 포화이온의 영향, 입자의 전기화학적 성질, 흡탈착 성질, 표면적과 등전점, 해성점토에 대한 압밀점토(壓密粘土)의 변형율(變形率)의 추정 등이 주로 연구되었다. 부가가치가 낮거나 폐기되는 광물을 이용하여 토양개량재 혹은 흡착제를 형성하는 연구가 알카리 처리에 의한 Zeolite 합성에 집중되었다.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.108-114
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• 2002

Cellular glass foam (CGE), the reprocessed glass, has a possibility as a component of vegetative propagation media of floricultural crops due to the its excellent air and water permeability, similar to that of perlite. An experiment was conducted to evaluate the rooting and growth thereafter of Kalanchoe blossfeldiana ‘Gold Strike’in media containing various volume ratios of granular rockwool, peat-moss, CGF and perlite. The particle size of CGF and perlite was 2.0~4.0mm and 1.2~4.0mm, respectively. Cuttings were rooted in a fog tunnel with a mean temperature of 18.2$^{\circ}C$ and RH of 66.7％ under a long day regime (14 h per day light period). Height, length of the longest root, stem diameter, no. of leaves, leaf area, percentage of rooted cuttings, shoot and root fresh weights, shoot and root dry weights, total chlorophyll concentration and physicochemical properties were measured. Cuttings rooted 100% in all treatments. Physicochemical properties in CGF and perlite-containing media showed little differences. The growth of rooted plants in the CGF-containing media was similar or rather superior to that in perlite-containing media. Consequently, CGF has a possibility as a vegetative propagation medium of Kalanchoe. To make wider commercial use of CGF, more demonstrative experiments and analyses are necessary.

• Journal of Chest Surgery
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• v.30 no.5
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• pp.512-516
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• 1997

We have experienced 66 cases of video assisted thoracic surgery(VATS) of spontaneous pneumothorax. The patients ranged in age from 1 Syears to 46years(mean age, 22.3years) and male patients were sixty three. The indications of video assisted thoracic surgery of spontaneous pneumothorax were recurrence, continuous air leakage, visible blabs on the chest X-ray & others. Infraoperative findings were as follows; blabs, pleural adhesion and pleural effusion. The operation was performed under general anesthesia wit double lumen endobronchial tube. Operative procedures included blebectomy and/or wedge resection of lung, vibramycin Pleurodesis with mechanical abrasion. In most cases, postoperative courses were uneventful and patients were discharged without significant complications. VATS provided the benefits of lesser postoperative pain, rapid recovery, short hospitalization, and smaller scar of wound. Conclusively VATS is a new interesting modality of surgical treatment of spontaneous pneumothorax and also can be extensively applicable in the diagnosis and treatment of other intrathoracic disease.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.31-36
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• 1997

This study was carried out to analyze the composition of landfill generation gas using vertical pipe wells installed at landfill. The characteristics of composed waste were examined by the open-cut test at H. landfill in Pusan. The waste compositions of landfill layer by Open-cut test indicated that organic matter was average $4.6{\sim}8.78%$ in each landfill. $CH_4$ compositions of gas in each landfill were $49.71{\sim}50.45%$(A-point), $50.39{\sim}53.74%$(B-point), and $58.76{\sim}61.62%(C-point), respectively. The chemical formula of organic matter left in the underground was $C_{36.3}H_{76}O_{30}N_{0.3}S_{0.1}$ Underground temperatures were changed to $18.8{\sim}25.8^{\circ}C$ when the ambient temperature was about $13.4^{\circ}C$. Temperatures with passed times in A, B and C-lysimeter were about $21.1{\sim}22.5^{\circ}C,\;30{\sim}32.5^{\circ}C$ and $35{\sim}38.5^{\circ}C$, respectively. After about 65 day, decomposition rates of organic matter in A, B and C-lysimeter were 9.9%, 14.9% and 22.3%, respectively.

• Journal of KIISE:Information Networking
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• v.35 no.3
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• pp.173-182
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• 2008

Promoting quality of streaming service in wireless networks has attracted intensive research over the years. Instable wireless channel condition causes high transmission delay and packet loss, due to fading and interference. Therefore, they lead to degrade quality of video streaming service. The IEEE 802.11 Working Group is currently working on a new standard called IEEE 802.11e to support quality of service in WLANs. And several schemes were proposed in order to guarantee QoS. However, they are not adaptable to network condition. Accordingly, they suffered video quality degradation, due to buffer overflow or packet loss. In this paper, to promote quality of video streaming service in WLANs, we propose a cross-layer architecture based on IEEE 802.11e EDCA model. Our cross-layer architecture provides differentiated transmission mechanism of IEEE 802.11e EDCA based on priority of MPEG-4 video frames and adaptively controls the transmission rate by dropping video frames through the efficient bandwidth estimation based on distinction of each AC. Through the simulation, proposed scheme is shown to be able to improve end-to-end qualify for video streaming service in WLANs.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.1
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• pp.53-66
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• 1998

This study was carried out to investigate the typical composition of food waste from municipal solid wastes (MSW) and unit food waste generation rates from different sources in the model cities and to study the food waste management system from unit household to composting facilities. The annual average food waste composition of MSW was determined as 49% in Taejon and 52% in Chungnam Province, respectively. No big difference in food waste composition was found among the different sources. Since the paper waste generally occupied the half of food waste, over 75% of MSW was found to be compostable or biodegradable. Per capita food waste generation rate, 200~250g/capita day was determined by the direct measurement from 32 households, while 380g/capita day for Chungnam Province and 400 g/capita day for Taejon were estimated by the load count analysis In the sanitary landfills. This difference means people contribute generating food waste at outside house approximately twice as much as that at inside house. Per capita food waste generation rates from several sources were determined as follows; 166~215g/capita day at municipalities, 400g/visitor day at a first class hotel, 170g/student day at a university restaurant. Food waste generation from restaurant was strongly dependant upon it's level or quality; 670g/capita day at the high level restaurant, 190g/capita day at the middle class and 60 g/capita day at the lower class restaurant. The food waste reduction rate in a In situ fermentor showed 30~40g/kg day.

• Journal of Chest Surgery
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• v.29 no.4
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• pp.397-402
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• 1996

A clinical study of 36 cases of pulmonary tuberculosis that had had a surgical resection during the period of 13 years from January 1979 to December 1992 was performed in the Department of Thoracic and Cardiovascular Surgery, Chonbuk National University Hospital The ratio between male and female was 3.5 1 and the age of peak incidence was in the 2nd and 3rd decades. The common prodromal symptoms were chest pain (38.9 %) and hemoptysis or blood tinged sputum (36.1 %). Preoperative diagnostic examination of sputum positivity for AFB stain despite antituberculosis chemotherapy was noticed in 22.8 oyo . Surgical indications were destroyed lobe or segment with or without cavity (58.3 oyo), mass unable to differentiate from lung cancer (16.7 %), total destroyed lung (13.9 %), bronchostenosis with atelectasis and distal bronchiectasis (11.1 %). Types of resection were pneumonectomy in 16.7%, lobec omy and segmentectomy 2.7%, lobectomy 50 %, segmentectomy 27.8%, and wedge resection 2.7%. Postoperatively, pulmonary function Improved compared to the preoperative examination, although these changes were not statistically significant. One patient died of ulcerative colitis due to drug hypersensitivity, and the postoperative complications were remnant dead space in 11.1 %, spreading of tuberculosis in 5.5%, and empyema with BPF in 5.5%.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.331-338
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• 2006

Coal combustion fly ash, which has a high available Si content and alkaline pH, was selected as a potential source of soil amendment in this study. Two field experiments were carried out to evaluate the possibility of heavy metal accumulation in silt loam (Pyeongtaeg series) and loamy sand (Nagdong series) of rice (Oryza sativa) paddy soils to which 0, 40, 80, and $120Mg\;ha^{-1}$ of fly ash were added. Rice yields increased significantly with fly ash application and the highest rice yields were achieved following the addition of around $90Mg\;ha^{-1}$ fly ash. Fly ash increased the soil pH but did not increase heavy metal uptakes of rice and heavy metal concentration in soils, due to very low concentration of heavy metals in the selected fly ash. Labile fraction of heavy metals (exchangeable + acidic fraction) was scarcely contained and most of them were stable and unavailable form (oxidizable and residual fraction). In conclusion fly ash could be a good supplement to an inorganic soil amendments without heavy metal contamination in paddy soils.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.1-7
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• 1997

In order to utilize fish by-products from the skipjack tuna (Katsuwonus pelamis) canning manufactures Lactobacillus buigaricus KCTC 3188 and L. piantarum KCTC 1048 were used as a starter culture for the preparation of fermented fish silage with skipjark tuna viscera. The optimum temperature and pH on barterial growth and lactic acid production of L. bulgaricus and L. plantarum in MRS broth were $35^{\circ}C$ and around pH 6.0, respectively. And the optimum concentrations of the carbohydrate sources added to the broths were $7\%$ for dextrose and $10\%$ for molasses on the basis of total weights of skipjack tuna viscera. The pH of acid treated skipjack tuna viscera silage (ASS) slightly increased from 4.0 to 4.5, while that of fermented skipjack tuna viscera silages by the use of lactic acid bacterias (FSS) was significantly declined from 5.9 to about 40 after 42 days of storage at $35^{\circ}C$. Though the content of volatile basie nitrogen (VBN) in ASS was lower than those of FSS after 42 days of storage at $35^{\circ}C$, VBN content in silages slightly increased from an initial value of $62\~65{\cdot}mg/100g$ to final value of $113\~155\;mg/100g$ over 42 days. The fermented silage by L. piantarum reached a maximum concentration of amino nitrogen and showed $81\%$ of hydrolysis degree after 4 days of storage at $35^{\circ}C$.