• Journal of the Korea Concrete Institute
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• v.14 no.6
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• pp.823-829
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• 2002

The composite frame system with reinforced concrete column and steel beam has some advantages in the structural efficiency by complementing the shortcomings between the two systems. The system, however has also a lot of problems in practical design and construction process due to the material dissimilarities. Considering these circumstances, this research is aimed at the development of the composite structural system which enables the steel beams to be connected to the R/C columns with higher structural safety and economy. Basically the proposed connection system is composed of four split tees, structural angles reinforced by stiffener, high strength steel rods, connecting plates and shear plates. The structural tests have been carried out to verify the moment transfer mechanism from beam flange to steel rods or connecting plates through the angle reinforced by siffener. The four prototype specimens have been tested until the flange of beam reached the plastic states. From the tests, no distinct material dissimilarities between concrete and steel have been detected and the stress transfer through wide flange beam - structural angle - high strength steel rod or connecting plate is very favorable.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.8
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• pp.1075-1081
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• 2010

Recently, the results of many studies have clarified the successful performance of magnetostrictive transducers in which a ferromagnetic patch is used for the transduction of guided shear waves; this is because a thin ferromagnetic patch with strong magnetostriction is very useful for generating and detecting shear wave. This investigation deals with bulk shear wave transduction by means of magnetostriction; on the other hand, the existing studies have been focused on guided shear waves. A modular transducer was developed; this transducer comprised a coil, magnets, and a thin ferromagnetic patch that was made of Fe-Co alloy. Some experiments were conducted to verify the performance of the developed transducer. Radiation directivity pattern of the developed transducer was obtained, and a test to detect the damage on a side drill hole of a steel block specimen was carried out. From the results of these tests, the good performance of the transducer for nondestructive testing was verified on the basis of the signal-to-noise ratio and narrow beam directivity.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.173-179
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• 2016

Purpose: This study is to help assist in the management of optical shops by using the importance sequence of optical shop selection attributes, which is related to the consumer's selection method of consumer, and by using the importance sequence of optical shop information sources which is related to a route for optical shop selection. Methods: Customer surveys were conducted from March 10 to March 31, 2015 targeting customers who have visited an optical shop in Seoul and Northern Gyeonggi-do regions. The analys method was descriptive statistics and data were analyzed by utilizing SPSS v.10.0 statistical package program. Results: The highest ranking five attributes among the importance of optical shop selection are "friendliness and politeness of staff", "cleanliness of an optical shop", "quick resolution of customer's complaints by staff", "eyes examination and glasses dispensing skill of staff", "customer's complaints and claims handling". The lowest ranking five attributes among the importance of optical shop selection are "provide free gifts", "scale or size of an optical shop", "opening time and closing time", "convenient parking facilities", "favorable countenance of staff". The two highestr ranking criteria among the importance of optical shop information sources are "previous utilization experience", "recommendation by a relative, a friend and a family etc". The two lowest ranking criteria among the importance of optical shop information sources are "advertisement" and "spatial exterior view of optical shop". Conclusions: It is shown that the important thing in management of an optical shop is an inner caliber like ability of ophthalmic optician, interaction with customers, and previous utilization experience rather than external factors like advertisement, exterior view, and bonus gift.

• Proceedings of the Korean Society of Community Living Science Conference
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• 2009.09a
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• pp.103-103
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• 2009

한국 최초의 벼 재배지이고 농경문화의 근원지인 김포시는 경기도 북서부지역에 위치하고 있다. 북쪽과 동쪽으로 한강을 사이에 두고 있고 강화만 및 한강 하구부 염하 등이 3면을 둘러싸여 있어 김포반도라 한다. 서쪽에 문수산(376m), 장릉산(150m), 수안산(147m) 등의 낮은 산들이 소구릉지를 이루고 있으며 한강에 의한 토사의 운반 퇴적으로 이루어져 농경에 적합한 김포평야를 이룬다. 이런 특징을 갖고 있는 김포지역 향토자원 조사를 위하여 고문헌, 군지, 학술지 등의 자료를 통해 총 563종의 향토자원 목록을 정리하였다. 향토자원의 유형분류를 해보면 인물 193종(34.3%), 자연생태환경 140종(24.9%), 유물유적 136종(24.2%), 민속풍속 79종(14.0%), 전통식품 특산품 15종(2.7%)의 비율로 나타났다. 이 중 활용성이 있는 것으로 판단되는 자원을 지역 전문가 협의회를 통해 1차 선발 평가하여 기본조사를 실시하였고, 향토자원의 가치, 산업화 가능성 평가를 통해 2차 심층조사 대상을 선정하였다. 김포시 향토자원 목록 총 563종 중, 179종이 기본조사 자원으로 선정되어 기본조사를 실시한 결과, 설화 전설자원이 34종(19.0%), 전통제전 자원이 19종(10.6%), 유적사적지와 건축자원이 각 18종(10.1%), 수변 및 해양자원 자원이 15종(8.4%), 조각 자원이 15종(8.4%), 마을자원이 10종(5.6%) 등으로 나타났다. 각 자원의 명칭을 보면 설화 전설은 선돌이 전설, 김삿갓의 일화, 형제투금, 애기봉전설 등이었고, 전통제전은 김포통진두레놀이, 손돌공 진혼제, 대명리 풍어제 등의 자원이, 유적사적지는 덕포진(사적 제292호), 수안산성(지방기념물 제159호), 장릉(사적 제202호) 등으로 조사되었는데, 특히 지석묘의 분포가 많았다. 기본조사 자원을 대상으로 지역전문가 2차 협의회를 통해 향토자원의 가치, 산업화 가능성 등을 평가하여 53종을 선정하였고, 유물유적 24종(45.3%), 민속풍속 12종(22.6%), 자연 생태환경 10종(18.9%), 전통식품 특산품 4종(7.5%), 인물 3종(5.7%) 비율로 나타났다. 향토자원 산업화는 생산물 품질고급화나 농산물 가공분야가 점차 감소하고 천연염색 공예, 관광, 문화상품 등으로 다각화되고 있으므로 김포시의 농촌문화와 전통지식기술자원이 지자체와 지역주민들에 의해 활성화되기를 기대한다.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.5
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• pp.430-435
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• 2013

This study is investigation of the characteristics for acoustic emission signal generated by destruction on glass fiber bundles and specimen that was machined composite materials surrounding the outside of GFRP cylinder. The Amplitude of acoustic emission signal gets bigger as the cutting angle of knife increases. Accordingly, the number of hits in destruction of composite materials specimen have more in longitudinal direction (longitudinal direction to the glass fiber) than in hoop direction (horizontal direction to the glass fiber) while the amplitude of signals were bigger in hoop direction than longitudinal direction. It was found out that the amplitude of the glass fiber breakage is more than 40 dB and that the amplitude of signal for matrix crack was less than 40 dB because matrix crack signal was not observed when threshold value is 40 dB and matrix crack signal suddenly appered when threshold value is 32 dB. The slope of the amplitude is related to the acoustic emission source and the slope of the amplitude of the horizontal and vertical directions are 0.16 and 0.08. In particular, The slope of the amplitude of longitudinal direction breakage appear similar to the glass fiber breakage and therefore Acoustic emission source of longitudinal direction breakage is estimated the glass fiber breakage.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.466-472
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• 2006

In order to develop materials of crab-like flavorant, taste compounds including physicochemical characteristics were analyzed in red snow crab cooker effluent(RSCCE) and hepatopancreas. The $30\;^{\circ}Brix$ was a suitable condition in from 1.5 to $40\;^{\circ}Brix$ RSCCE by sensory evaluation. Lactic acid and succinic acid were major compounds in non-volatile organic acids detected in both $30\;^{\circ}Brix$ RSCCE and hepatopanceras. The 5 compounds such as AMP, HxR, IMP, ATP and GMP were major in ATP related compounds of $30\;^{\circ}Brix$ RSCCE, whereas 3 compounds including IMP, GMP and Hx in hepatopanceras. The content of total free amino acids in hepatopancreas was 5.6 times higher than in $30\;^{\circ}Brix$ RSCCE. The major compounds in $30\;^{\circ}Brix$ RSCCE were followed by methionine, lysine, arginine, valine, histidine, alanine, hydroxy proline, and glycine in that order, whereas methyl histidine, leucine, alanine, glutamic acid, glycine, valine, threonine, taurine, isoleucine, and serine were followed in hepatopancreas. By adding 0.5%(w/w) hepatopancreas in $30\;^{\circ}Brix$ RSCCE, crab meat-like odor was kept high level by sensory evaluation.

• Korean journal of food and cookery science
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• v.21 no.5
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• pp.709-716
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• 2005

The aim of this study was to determine the optimal cooking conditions for astringent persimmon concentrates. With increasing time of concentration, the moisture contents and L-, a- and b-values all decreased, whereas the brix level and viscosity increased. The crude protein, fiber and ash increased and the vitamin C decreased by concentrating. The pH was the lowest at 23 hrs of boiling concentration. With longer boiling concentration time, the fructose, glucose, and sucrose levels increased but the maltose level decreased. The DPPH radical scavenging effects of astringent persimmon concentrates were more than 92%. The total phenolics, flavanol tannin, leucoanthocyanin, and chlorogenic acid levels increased with longer boiling concentration time. In the sensory evaluation of the astringent persimmon concentrates, overall acceptability was the best at the 23-hr boiling concentration. From the above results, the 23-hr boiling, astringent persimmon concentrates could be useful for cooking in terms of obtaining the high amounts of phenolic compounds as functional compounds and overall acceptability.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.4
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• pp.473-485
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• 2015

The problems for non-rotating of a disc cutter proceed from the faults in inner parts of the disc cutter such as the leak of hydraulic fluid, the intrusion of tunnel mucks and water, overloading, overheating, poor assembly and substandard material. The rotating of a disc cutter is an indicator to show that the inner parts of disc cutter is operable, although the rotational torque depends on the extent of the damage. Therefore, the key in the problems for non-rotating of disc cutter is to maintain that the tapered roller bearings are working properly. This study aims to investigate the inner parts disassembled from disc cutters applied to the field tests in order to help decision for reuse of the disc cutters. As results, surface finishing to remove the scratch on the load zone of the hubs is needed, with the intent to reuse a hub. And the investigation of lapping surface by optical microscope of floating seals and the contamination test of oil need to be performed for reuse of a disc cutter. Especially, the analysis results show that the floating seals play a key role in the normal operation of bearings. There is nothing significant to report in the rest parts such as bearing, shaft, seal retainers.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.547-559
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• 1994

To effectively utilize fish skin wastes from marine manufactory, the optimal extraction conditions to prepare gelatin from fish skins of Alaska pollack, cod and yellowfin sole were investigated. In addition, the physical properties of the fish skin gelatins prepared under the optimal extraction conditions were compared with the commercial animal skin gelatin. The conditions for extraction of gelatins from fish skins were as follows ; The skins were limed with 1.0~1.5%(w/v) calcium hydroxide solution. The fish skin gelatins were extracted with 6~7 volumes of water(pH 6.0~7.0) for 5hrs at $40{\sim}50^{\circ}C$, and the yield of Alaska pollack skin gelatin extracted under the above conditions was higher than those of cod and yellowfin sole skins. The heavy metal contents, jelly strength and electric conductivities of fish skin gelatins were lower than those of a commercial gelatin(bovine skin), but the viscosity and isoelectric point were higher. The amount of amino acid in fish skin, such as gelatin, glutamic acid, serine, threonine, methionine and cysteine, were higher than those in pig and ox skin. However, the contents of hydroxyproline and proline were lower.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.95-98
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• 2003

전 세계에 위성이동통신 서비스를 제공하고 있는 인마새트 시스템은 해사통신 및 선박의 안전운항을 목적으로 UN산하 국제해사위성기구(INMARSAT: International Maritime Satellite Organization)로 설립되었다. 그 후 기존에 제공하던 해상 위주의 서비스 외에 항공 및 육상 이동통신서비스가 추가되면서 국제이동위성기구(INMARSAT: International Mobile Satellite Organization)라는 이름과 병행하여 사용하여 오다가 최근 민영화되었다. 이에 따라 인마새트는 육상, 해상, 항공서비스를 제공하면서 86개의 회원국으로 운영되어오다가 민영화되면서 이들 회원국은 모두 투자사로 전환되었다. 하지만 기존에 제공하여온 해상조난안전통신 등 공익성을 갖는 기능에 대해서는 향후에도 지속적인 서비스가 제공되도록 별도로 IMSO(International Maritime Satellite Organization)라는 감독기관을 두어 관장하고 있다. 인마새트는 전세계적으로 글로벌 위성이동통신 서비스를 최초로 제공한 이래 아직까지도 해상, 육상, 항공 등 전 분야에 통신서비스를 제공하는 유일한 사업자이다. 더구나 최근 저궤도 위성을 이용한 GMPCS의 성장추세가 예상보다 크게 둔화되면서 상대적으로 비용이 저렴한 정지궤도 위성 시스템인 인마새트 서비스가 더욱 활성화되는 추세이다. 이에 인마새트 서비스를 위한 신형 장비도 추가 개발되고 있으며 서비스 영역이 확장되는 등 그 중요성이 부각됨에 따라 향후 상당기간동안 인마새트 시스템에 부가기능을 추가하면서 재난시 비상연락수단은 물론이고 일상적인 통신수단의 영역까지 확대될 것으로 전망된다.인 방법이다. 활성물질의 생성시간과 가공시간은 불과 수십 $\mu\textrm{s}$ 및 수 sec 에 불과하므로, 1 kton/h 용량의 수산기활성제 제조장치의 환산소비동력은 약 200 kW이고, 장치의 체적은 10~30 ㎥의 공간으로 충분하므로, 소형선박으로 상당면적의 적조피해를 효과적으로 해결할 수 있다.의 특성을 이용하여 워터마크를 삽입한다.송 시스템을 구현될 수 있음을 검증하였다.출량을 비교한 결과 토사 유출 억제효과는 한지형과 나지형잔디들의 혼합형(MixtureIII)과 자생처리구(MixtureV), Italian ryegrass와 자생식물의 혼합형(MixtureIV)등에서 비교적 낮은 수치를 토사유출량을 기록하였다. 이러한 결과는 자생식물들이 비록 초기생육속도는 외래도입초종에 떨어지지만 토사유출의 억제효과면에서는 이들 외래초종에 필적할 수 있음을 나타낸다고 할 수 있겠다.중량이 약 115kg/$m^2$정도로 나타났다.소 들(환경의 의미, 사람의 목적과 지식)보다 미학적 경험에 주는 영향이 큰 것으로 나타났으며, 모든 사람들에게 비슷한 미학적 경험을 발생시키는 것 이 밝혀졌다. 다시 말하면 모든 사람들은 그들의 문화적인 국적과 사회적 인 직업의 차이, 목적의 차이, 또한 환경의 의미의 차이에 상관없이 아름다 운 경관(High-beauty landscape)을 주거지나 나들이 장소로서 선호했으며, 아름답다고 평가했다. 반면에, 사람들이 갖고 있는 문화의 차이, 직업의 차 이, 목적의 차이, 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을