• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.303-311
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• 1996

The microflora changes of 10 water-controled treatments combined with livestock manures(pig, chicken) and bulking agents(sawdust, paper sludge) were investigated. The B/F values of the P-1 and C-1(65%, $H_2O$) treatments were 3571 and 5400 respectively, but those of the P-4 and C-4(50%, $H_2O$) treatments showed very low values, 667 and 334, respectively. The B/F values tended to increase with higher water content of the treatments. In the composting processes, the successions of microflora, adapting the compost environments, took place via fluctuating temperature. In the high temperature period, the numbers of mesophilic bacteria and fungi decreased, but that of the spore forming bacteria increased. However, the number of mesophilic bacteria inereased during the cold period. The B/F values of compost ranged 25-300, which indicates a decrease in the quantity of bacteria. The time required for the temperature of compost to reach $60^{\circ}C$ showed different patterns. There was no pathogenic microorganism in the treatments which reached a high temperature in a short period of time, but, in the treatments which reached a high temperature over a Long period of time, the pathgenic microorganism was not still alive.

• Geotechnical Engineering
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• v.14 no.6
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• pp.113-125
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• 1998

At the end of 1997 about 3 million tons of coal ash was produced as byproducts from the coal fired electrical power plants in Korea. Only about 27% of that byproducts was utilized as the admixtures of cement and concrete industry. But the large quantity of coal fired fly-ash has been used as the soil improvement materials in other countries. So the aim of this study is the estimation of the applicability of the coal fired fly-ash as microfine grouting materials by admixing the superfine particles which were separated from the coal fired fly-ash for the higher values. The 6 types of specimens were manufactured in the laboratory for the purpose of estimating the chemical and physical properties of cement and grouts. These specimens consisted of 2 specific surfaces of 6, 000 and 8, 000$cm^2$/g in Elaine method. And these specimens are devide into 3 ratios (30%, 50%, 70%) of fly-ash by weight. From the estimated properties of the coal fired fly-ash microflne cements and grouts, 50% fly-ash is the most suitable ratio for grouting materials. However, further study of durability is necessary for using fly-ash grouts practically at the field projects. The higher content of the unburned carbon of fly-ash increases the thinner layer of carbon on the surface of solution of grouts, and requires more quantity of surface active agent. As a results of this study, it is found that the microfine fly-ash is very useful as a good grouting material if 50% of fly-ash is added with the microfine portland cement. So, in the near future, if the coal fired fly-ash is able to be used as grouting material in Korea, the demand of fly-ash will increase rapidly.

• Korean Journal of Construction Engineering and Management
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• v.15 no.6
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• pp.63-70
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• 2014

Deconstruction of the building must be applied firstly in order to improve recycling and reuse of construction wastes. In this study have done a case study for deconstruction of an apartment. All construction waste(CW) which will be generated during deconstruction was examined in each part of the building. Because drawing did not exist in most of the old building, we drew up floor plans of buildings. After analyzing these drawings, estimated quantities of CW. It was measured working time of labor and equipments for deconstruction and general demolition on each building of the apartment. In addition, it was proposed in the volume and weight per unit after analyzing detailed measurement of CW which was generated in the process of deconstruction and traditional demolition. It suggested recovery rate at a site, volume and weight conversion factors, and waste basic unit per area that based on the results of comparative analysis on the amount of CW which is calculated from drawing and generated at a site. These factors will be used fundamental materials for estimating quantities and treatment cost of CW, and scheduling of works.

• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.329-340
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• 2016

Increase in demotion and repair works on buildings in the construction market generates a large amount of construction waste. Recycling of construction waste is important for saving of resources, preservation of environment and constant advance of the construction industry. Accordingly, the environmental and economic value of recycled aggregate, which is produced after waste concrete is crushed, is increasingly highlighted. It is generally known that compared to concrete made of ordinary aggregate, concrete made of recycled aggregate has low quality, and the low quality is dependent on the amount of the bonding heterogeneous (cement paste and mortar) as well as the amount of the pores within the bonding heterogeneous. Reports on carbonation mechanism shows that the pores of cement-based materials are filled up by the progress of carbonation. Therefore, this study aims at an estimation of the period for optimum carbonation reforming appropriate for the thickness of the bonding heterogeneous of recycled aggregate, based on carbonation mechanism, with a view to improving the product quality by means of filling up the pores of the bonding heterogeneous of recycled aggregate. This study drew the carbonation depth according to the passage of age by calculating the bonding ratio and bonding thickness of the bonding heterogeneous as against the particle size distribution of recycled aggregate as well as by chemical quantitative analysis according to the age of accelerated carbonation of mock-up samples imitating bonding heterogeneous. Based on the correlation between the age of accelerated carbonation and carbonation depth, this study also proposed the estimated period of carbonation reforming of recycled aggregate appropriate for the thickness of the bonding heterogeneous.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.142-148
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• 1998

Video-assisted thoracic surgery(VATS) is emerging as a viable alternative to thoracotomy when surgical treatment of spontaneous pneumothorax is required. 20 patients with spontaneous pneumothorax underwent bullectomy between July 1995 and May 1996. The patients were divided into two groups : Control group ; the patients who received with mid-axillary approach(n=10), Experimental group ; the patients who received with VATS (n=10). The results were as follows ; 1. The total sex distribution was male predominance (male:female=17:3). Mean age of control group was 29.6$\pm$9.8 years and experimental group was 27.2$\pm$11.9 years. 2. The mean period of postoperative chest tube indwelling duration and hospital stay were 3.3$\pm$0.8 days and 7.9$\pm$1.2 days in control group and 2.1$\pm$0.9 days and 5.2$\pm$3.1 days in experimental group(p=0.005 and p=0.02). 3. The mean time of operation, vital signs and arterial blood gas analysis did not showed any statistical differences between the groups. 4. Percent recovery of tidal volume and forced vital capacity were significantly improved in experimental group comparing with control group (p<0.05). 5. The patients undergoing VATS experienced significantly less postoperative pain and limitation of motion. In conclusion, VATS is safe and offers the potential benefits of shorter postoperative hospital stays and less pain with cosmetic benefits.

• Korean Journal of Rural Living Science
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• v.2
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• pp.1-23
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• 1991

농촌주민들의 영양 섭취실태에 대한 동향을 요약해 보면 1. 총 섭취식품중 약 90% 정도를 식물성식품으로써 섭취하고 있으며, 곡류가 차지하는 비율은 점차 감소되는 반면 콩류, 채소류 및 과일류의 섭취 비율은 현저히 증가하고 있다. 2. 총 열량섭취는 감소하는 추세이고 총열량에 대한 탄수화물 :단백질 :지방의 비율이 74 : 12 : 12의 수준이다. 총 단백질 섭취에 대한 동물성 단백질 섭취율은 36%로써 질적으로 바람직하게 변화되고 있다. 칼슘의 섭취수준이 권장량의 90%정도로서 조금 부족한 듯 하지만 철분, 비타민 등 대체로 영양섭취상태는 많이 개선되었음을 알 수 있다. 3. 농촌 영아들의 경우는 모든 영양소가 권장량에 현저히 미달되는 상태이다. 이유식품 개발 및 이유 방법에 대한 상담 지도가 적극 필요한 실정이다. 4. 새마을 유아원의 설치 및 유아급식의 혜택으로 농촌 유아들의 영양 섭취 상태는 두드러지게 개선되었으나 철분섭취 상태는 권장량에 미달되는 실정이다. 취학전 아동의 영양향상을 위해서는 유아 교육시설 확충 및 간식의 중요성에 대한 농촌 주부 대상의 영양 교육 확대 실시가 요청된다. 5. 국민학교 아동들에게서는 빈혈의 발생 빈도가 높게 나타났다. 성장 발육기에 있는 이들의 심신발달에 필요한 영양공급 및 올바른 식습관 형성을 위해서는 학교에서 일정한 지도 목표를 설정하여 계획적으로 실시하는 학교 급식의 필요성이 강조된다 하겠다. 6. 청소년기 및 임신 수유부의 경우도 철분의 섭취상태가 부족하기는 하지만, 철 결핍성 빈혈증상이 나타날 정도는 아니고 영양섭취상태도 대체로 양호하다. 7. 노인들의 식품 영양 섭취실태는 권장량에 크게 미달되는 실정이기는 하지만 혈액검사의 수치들이 대체로 정상인 범위에 있고 건강상태도 양호한 편이다. 식품 개발 및 조리법에 관해서 요약해 보면 1. 식량수급의 안정을 기하고자 다수확 품종인 통일계통 쌀의 취반 및 가공적성에 대한 검토가 진행되었으며, 잡곡류 및 감자류의 효과적인 이용을 위해 복합분의 사용에 의한 식품가공 적성에 대한 연구들이 실시되었다. 2. 콩류에 대한 연구로는, 기름을 추출하고 남은 탈지대두박의 단백질 식품으로의 이용을 위해 추출법의 검토 및 탈지대두박을 이용하는 두부제조법 등 다각적으로 식품에의 적용에 관해 연구가 진행 되었다. 3. 발효식품 중 김치에 대해서는 농촌지역에서 제조되는 김치의 종류와 섭취실태에 관한 연구 및 김치의 저장성을 증진시키기 위한 일련의 검토가 있다. 간장, 고추장, 된장에 대해서는 Koji를 이용한 개량식 제조법 및 팽화시킨 곡분을 사용하는 간편 제조법, 비용 절감을 위한 대체원료 이용에 대한 연구 등이 진행되었다. 4. 이밖에도, 병조림 제조방법, 어린이를 위한 고영양 보충식 개발, 생선의 폐기 부분을 이용하여 칼슘 급원 식품으로서의 유용성에 관한 조리과학적 검토 등이 실시되었다. 식습관 및 식생활 관리 지도에 관한 연구에 의하면, 농촌여성의 농업역할이 가중되면서 자녀들의 식생활을 방임하기 쉬운 실정이므로 유아 교육시설 및 학교 급식 등을 통해서 바람직한 식습관 형성을 위한 프로그램이 개발되어져야 하며, 한편, 식생활 담당자인 농촌주부에 대한 규칙적이고 정확한 영양교육이 이루어져야 하리라 본다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.1922-1931
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• 1999

A multicast traffic’s feature is the function of providing a point to multipoints cell transmission, which is emerging from the main function of ATM switch. However, when a conventional point-to-point switch executes a multicast function, the excess load is occurred because unicast cell as well as multicast cell passed the copy network. Additionally, due to the excess load, multicast cells collide with other cells in a switch. Thus a deadlock that losses cells raises, extremely diminishes the performance of switch. An input queued switch also has a defect of the HOL (Head of Line) blocking that less lessens the performance of the switch. In the proposed multicast switch, we use shared memory switch to reduce HOL blocking and deadlock. In order to decrease switch’s complexity and cell's processing time, to improve a throughput, we utilize the method that routes a cell on a separated paths by traffic pattern and the scheduling algorithm that processes a maximum 2N cell at once in the control part. Besides, when cells is congested at an output port, a cell loss probability increases. Thus we use the Output Memory (OM) to reduce the cell loss probability. And we make use of the method that stores the assigned memory (UM, MM) with a cell by a traffic pattern and clears the cell of the Output memory after a fixed saving time to improve the memory utilization rate. The performance of the proposed switch is executed and compared with the conventional policy under the burst traffic condition through both the analysis based on Markov chain and simulation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.635-641
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• 2000

In order to utilize the protein source from a fish proessing by-product, cod was hydrolyzed with various enzymes such as tuna pyloric caeca crude enzyme (TPCCE), a-chymotrypsin, trypsin, papain and pronase E. The TPCCE hydrolysate acquired the highest sensory properties on taste, odor and color. The resultant cod rfame protein hydrolysate (CFPH) which was hydrolyzed with TPCCE, was separated through a series of ultrafiltration membranes with molecular weight cut-off (MWCO) of 30, 10, 5 and 1 kDa, and four types of permeates in cluding 30 K (permeate from 30 kDa membrane), 10 K (permeate from 10 kDa membrane), 5 K (permeate from 5 kDa membrane) and 1 K (permeate from 1 kDa membrane) were obtained. The natural sauces were prepared with 30 K, 10 K, 5 K and 1 K hydrolysate, and the sauce prepared with 1 K hydrolysate was the best score in sensory evaluations. In addition the mixed sauce prepared with 1 K hydrolysate and commercial soy sauce was similar to commercial sauce in sensory properties. These results suggest that the mixed sauce would be utilized as the substitute of acid-hydrolysis sauce.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.635-641
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• 2014

Archaeological waterlogged woods require a process of dimensional stabilization for their conservation. PEG is the most widely used in the conservation of archaeological waterlogged wood. One of the easiest and commonly used methods is the impregnation of 40% polyethylene glycol followed by vacuum freeze drying. However, the waste fluid produced from the PEG treatment is black in color and has a severe odor due to the organic matter extracted from the wood. Thus It cannot be recycled and it was just thrown out. Color of waste fluid can be decolored with oxidation reaction by hydrogen peroxide. Properties of PEG before and after preservation treatment, and after oxidation with $H_2O_2$ were not changed. Dimensional stability of archaeological waterlogged Salix koreensis Andersson was studied with pure or recycled PEG. The ratio of impregnation solutions were 10:0, 7:3, 5:5, 3:7, 0:10 (pure PEG : recycled PEG). Impregnation process was carried out by putting the wood specimens 10% PEG solution for 5days, 20% for 5 days, 30% for 5 days finally 40% for 5 days. All of the specimens showed the weight change rate of 25%. SEM results provided that the dimensional change of were less than 4% PEG impregnated specimens. Comparing with pure PEG impregnation system, conservation precess mixed PEG also showed no significant changes. Conclusively, the recycled PEG can be used for archeological waterlogged wood conservation precess.

• Journal of the Korean Society of Radiology
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• v.10 no.4
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• pp.285-290
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• 2016

The purpose of our study was to retrospectively evaluate the cause of a decreased calcium score of follow-up studies on coronary artery calcium scores (CACs) computed tomography (CT). The subjects were healthy 100 people(85 males $60.6{\pm}6.9$ years, 15 females $67.2{\pm}7.3$ years). The subjects decreased CACs were divided into 4 subgroups depending on Agatston classification, minimal (1-10), mild (11-100), moderate (101-400), severe (400<). As a result of decreased CACs were scan location disagreement 51%, motion artifact 26%, equipment changes 14%, operator mistakes 5%, input miss 2%, image loss 1%, arrhythmia 1%. In the mild group, the most common decreased CACs were 49 people. In the minimal group, the most significant variation reduction has occurred to 6 people. Scan location disagreement was considered a partial volume effects due to the scan starting position. It showed less than 100 CACs a high variation (19.7%) in more than 100 CACs, a lower variation (2.2%), these could be seen that the variation range is different that can be tolerated according to the calcification score. Motion artifact factor was found in 26%, which is so closely related to the preceding tests that affect the higher heart rate like this pulmonary function test, exercise stress test.