• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1285-1289
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• 2008

Increasing the flood control capacity's link that is enforcing to existing dam by unusual change of weather, While build planing construction by exiting spillway of tunnel type to dam, could know that part bed rock is formed as is different with design. Grasped topography of research area and geology state to definite distribution aspect of different bed rock, Place that achieved Surface geological Survey and correct Survey is difficult in some section enforced Electrical resistivity dipole-dipole investigation. Grasped stratigraphy distribution confirmation and fracture or weathering zone making out siding 2D-Resistivity Electrical resistivity diagram and Reverse analysis diagram, examining closely soil weathered rock rock's distribution state, established stability countermeasure plan

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1998년도 PROCEEDINGS OF THE 15TH KACG TECHNICAL MEETING-PACIFIC RIM 3 SATELLITE SYMPOSIUM SESSION 4, HOTEL HYUNDAI, KYONGJU, SEPTEMBER 20-23, 1998
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• pp.117-121
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• 1998

The Rapid Expansion of supercritical fluid Solutions (RESS) process was applied to particles coating. Experiments were conducted in a fluidized bed with an internal nozzle in the center of the reaction tube. Microcapsules (mean particle size : 49$\mu\textrm{m}$) prepared by spray drying method were used as the core particles. Supercritical CO2 solutions of paraffin were expanded through the nozzle in to the bed that was fluidized by air. Surface morphology prepared particles was observed by SEM. For the inspection of particle size change, particle size distributions were measured before and after coating. The releasing behavior of Mg2+ ions inspected by AA.

• Structural Engineering and Mechanics
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• 제60권6호
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• pp.923-937
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• 2016

The common prospect in diminishing mine-blast vibration is decreasing vibration with increasing distance. This paper indicates that, contrary to the general expectancy, vibration waves change their forms when they are travelling through the low velocity layer like coal and so-called guided waves moving the vibration waves to longer distances without decreasing their amplitudes. The reason for this unexpected vibration increase is the formation of guided waves in the coal bed which has low density and low seismic velocity with respect to the neighboring layers. The amplitudes of these guided waves, that are capable of traveling long distances depending on the seam thickness, are several times higher than that of the usual vibration waves. This phenomenon can many complaints from the residential areas very far away from the blasting sites. Thus, this unexpected behavior of the coal beds in the surface coal mines should also be considered in vibration minimization studies. This study developed a model to predict the effects of guided waves on the propagation ways of blast-induced vibrations. Therefore, vibration mitigation studies considering the nearby buildings can be focused on these target places.

• 융합경영연구
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• 제2권3호
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• pp.20-25
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• 2014

Comfortable sleeping itself is thought to be very much important to have great influence upon remaining lives. Bed-clothes can be an essential factor of comfortable bedding. Korea that has four seasons requires different blanket each season. The Koreans make change of use of the quilt at least 2 to 3 times a year. The quilt may vary depending upon use of either Ondol or bed. Brand bedding governs quilt market. Brand bedding shops have good cognition of customers to be located at the place easy to find out and to have various kinds of products and excellent designs and to take the lead in all of the areas. Non-brand bedding products are difficult to compete with brand products at the bedding market. This study investigated cases of not only management of non brand bedding but also competition between brand bedding and non brand bedding. First, How does non brand bedding elevate competitiveness to win at competition with brand bedding? Second, How dose non brand quilt's approach to consumers and sales strategies?

• 한국수자원학회논문집
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• 제40권10호
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• pp.755-768
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• 2007

본 연구는 자갈하천에서 실측한 자료를 사용하여 유량 변화에 따른 조도계수의 변화를 분석하고, 기존 조도계수 경험식의 적용성을 검토하는 것이 목적이다. 실측자료를 이용한 조도계수의 산정을 위하여 미 지질조사국의 NCALC 모형을 이용하여 대상구간의 조도계수를 산정하였고, 산정된 결과를 4가지 경험적인 방법에 의해 산정된 조도계수와 비교하였다. 분석결과 기존의 경험적 방법들은 홍수기에 국한하여 근사적인 해를 제공할 수 있으나 판단의 주관성, 방법에 따른 결과의 차이 등으로 인하여 산정결과의 불확실도가 높을 것으로 판단되었다. 평저수기의 조도계수는 기존 경험적 방법으로 산정이 어려울 것으로 나타났으며, 특히 Manning 공식을 이용하여 조도계수를 산정하는 경우, 상한치와 하한치의 범위가 크므로 사용 시 주의가 필요함을 알 수 있었다. 그리고 평저수기에도 조도계수와 하상입도가 상관성이 있는 것으로 확인되었으나 홍수기의 상관성과 다르게 나타남을 확인하였다.

• 한국대기환경학회지
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• 제25권6호
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• pp.503-511
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• 2009

VOC mixture was fed to a trickle bed air biofilter (TBAB) with step-change in influent mixture concentrations from 50 ppmv to 1,000 ppmv, corresponding to loadings of $5.7\;g/m^3/hr$ to $114.1\;g/m^3/hr$. VOC mixture was an equimolar ratio of two aromatic VOCs, i.e., toluene and styrene, and two oxygenated VOCs, i.e., methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK). The TBAB system employed backwashing as biomass control. The experimental results showed that a critical loading rate for VOC mixture removal was determined to be about $60\;g/m^3/hr$, and critical loading rates for individual VOCs in the mixture were different. Specifically, toluene content in the mixture played a major role in the biofilter overall performance. As VOC mixture was fed beyond the critical loading rate, reacclimation of the biofilter to reach the 99% removal efficiency following backwashing was delayed, which was a critical factor in the biofilter performance. In the mass balance analysis, 63.8% of the carbon equivalent in VOCs removal was used for $CO_2$ production during the experimental runs. The 82.6% nitrogen utilized in the biofilter was contributed to microbial cell synthesis. The obtained results were compared against consistently high efficient performance of TBAB for VOC mixture by employing backwashing as biomass control.

• 공업화학
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• 제7권6호
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• pp.1027-1033
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• 1996

쌍극자물질에 전자파를 조사하면 그 파동의 변화에 따라 분자가 진동하며, 이웃 분자와 마찰을 일으켜 물질 내부로부터 가열되는 독특한 현상을 보인다. 따라서 고체인 전자파흡수제에 흡착시킨 쌍극자 기체를 microwave energy로 쉽게 파괴할 수 있다. 연소기기 배출가스에서 산성가스 제거공정 개발을 위하여 이 방법에 의한 산성가스 분해실험을 실시하였다. Calcined char는 전자파흡수제 및 가스 흡착제로서의 역할을 하는데, NO와 $SO_2$를 함유한 표준가스를 char bed내로 통과시키면서 microwave를 조사하였다. Microwave가 조사되고 있는 20 gram의 char bed를 통과하는 동안 95% 이상의 NO와 70% 이상의 $SO_2$가 환경적으로 무해한 단체원소로 분해되었으며, 분해된 원소 중 산소기는 char의 기공내에서 탄소와 반응하여 $CO_2$를 형성하며 char의 기공도 및 표면적 증대효과를 가져왔다. 일반적인 상업적 연소공정에서 처럼 이보다 낮은 농도에서는 거의 완전한 분해가 가능하리라 보여지며, 대기오염 방지에 좋은 방법이 되리라 믿어진다.

• 생명과학회지
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• 제20권11호
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• pp.1656-1661
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• 2010

난황단백질 가수분해를 위한 알칼리성 단백질분해효소를 5가지 담체 Duolite A568, Celite R640, Dowex-1, Dowex 50W 그리고 Silica gel R60 에 고정화하였다. Duolite A568의 경우에 24.7%의 최대 고정화 효율을 나타내었다. 자유 효소와 고정화 효소에 대한 최적의 pH는 각각 8과 9였고, 최적의 pH는 고정화에 의해 염기성으로 1만큼 증가하였다. 그러나 최적 온도는 자유 효소와 고정화 효소 모두 $50^{\circ}C$로 같았다. 고정화 효소가 자유 효소에 비해 높은 열 안정성을 보였다. 재사용 회분식 공정에서 10 cycle 동안 효소활성은 초기 활성의 86%를 유지하였다. 연속 공정을 위한 충진층 반응기에서 여러 유속에 대한 장기 조업에서 효소 활성의 안정성 평가하였는데 낮은 유속일수록 높은 활성을 유지하였다. 연속 조업에서 casein과 난황 단백질을 사용하여 원료에 대한 고정화 효소의 활성에 대한 영향을 조사하였다. 96시간 연속 조업에서 casein의 경우는 초기 활성의 83%를 유지하였고 난황 단백질의 경우는 초기 활성의 61%를 유지하였다.

• 한국염색가공학회지
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• 제34권4호
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• pp.241-249
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• 2022

As for military backpacks in Korea, utility backpack products equipped with various functions along with comfort and convenience are being developed. As a result, the volume and weight of the backpack increase, and many lightweight studies of the materials forming the backpack are being conducted. This study is a basic study on frame lightweight using fiber-reinforced composites to deal with aluminum, a back frame that maintains the shape of a backpack and provides stability when worn by combatants. As is known, only fiber-reinforced composites have sufficient light weight and mechanical properties, but the mechanical properties were reviewed by drilling holes to maximize the light weight. Tensile strength and flexural strength were measured by drilling 6mm, 12mm, 18mm, and 24mm holes, and the tensile strength and flexural strength were measured when 1, 3, 5, and 7 holes of 12mm were increased. As a result, even when the number of holes was increased, tensile strength did not change significantly, and the flexural strength showed to be higher in the case of 3 holes and 5 holes than in the case of 1 hole.

• 한국직업건강간호학회지
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• 제12권1호
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• pp.31-38
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• 2003

This study is an attempt to analyze the physical load by the type of the nursing tasks at the neurosurgical ICU nurses through the quantitative analysis of the working postures by the type of the nursing tasks with the OWAS(Ovako Working Postures Analysis System). Data collection was conducted through the video recording of the 13 nurses working at the neurosurgical ICU. For the analysis of the work postures by the type of the nursing tasks, and were interviewed regarding the subjective degree of the difficulties with the work postures related to the tasks. Collected data was analyzed through the WinOWAS program. The results were as follows : AC3 or AC4 tasks among the 18 nursing tasks types are "occupied bed making and change of the patient gown", "back massage", "suction", "elimination management", "change of position", "adjustment of bed", "helping the patient to move","measurement of CVP"and "measurement of urine volume". It appears that these tasks are harmful to the musculoskeletal system and the improvement or change of the work is required. The results stated above indicate that improper working postures during the nursing tasks influence the musculoskeletal system. Therefore, making use of assistant devices for the improvement of the working environment at the nursing tasks, based on human technological diagnoses, is required regarding the duty types with massive work pressure known to be harmful to the musculoskeletal system among those performed by the nurses. And there is a need of the education about the employment and maintenance of the vocational back pain prevention.