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Development of Automatic Rewetting System for Rough Rice Stored in Round Steel Bin with Stirring Device -Adsorption characteristics of rough rice- (원형철제빈용 벼 자동흡습장치 개발에 관한 연구(I) -벼의 흡습특성-)

  • Kim, J. Y.;Keum, D. H.;Kim, H.;Park, S. H.
    • Journal of Biosystems Engineering
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    • v.26 no.5
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    • pp.469-474
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    • 2001
  • Milling the rice with low moisture requires more energy, produces more cracked rice, and results in reducing taste of cooked rice. Accordingly, it is necessary to add moisture to the rice with low moisture to obtain optimum moisture level for milling and taste of rice. This study was performed to evaluate the influence of initial moisture content and absorption rate on rice crack, milling energy and whiteness of milled rice and to obtain the information for design of rewetting system mounted on stirring device in grain bin. The tests were conducted for the four levels of initial moisture content in the range of 11.4 to 14.5%(w.b.) and six levels of absorption rate in the range of 0.04 to 1.0%, w.b./hr. In the case of lower moisture content below 12%(w.b.), crack ratios of brown rice were remarkably high regardless of initial moisture contents. Therefore, it was found that rough rice below 12%(w.b.) in initial moisture content could not rewetted by spraying water without crack generation of low level. Absorption rate must be below 0.3%, w.b./hr to maintain crack ratio increase of less than 1% regardless of initial moisture contents. In the case of allowable crack ratio increase of 2% and 5%, it was found that the maximum absorprion rate was respectively 0.6%, w.b./hr and 1.0%, w.b./hr in the initial moisture content of above 13.5%(w.b.). Rewetting the rough rice in moisture content of 11.4 to 14.5%(w.b.) to 14.3 to 16.9%(w.b.) decreased milling energy consumption by 15.9 to 22.3%. The effect of energy saving was higher in the samples of higher initial moisture content. Whiteness of milled rice was decreased by 0.5 to 1.5.

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Development of 80W LED Lighting Equipment for Broadcasting System (방송시스템용 80W LED 조명장비의 개발)

  • Lee, Dong-Yoon
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.10 no.6
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    • pp.506-511
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    • 2017
  • LED lighting, which many companies are pursuing commercialization, is a representative green energy technology. However, the LED lighting for broadcasting image should have high output and easy portability compared with general LED lighting devices for street lamps, advertisement or transportation devices. Therefore, while shooting a broadcast image if you use LEDs as a substitute light source for halogen lamps and fluorescent lamps that are large in size and uncomfortable to handle it is expected that the lightening of the equipment will activate the broadcasting image lighting equipment industry. After considering the mass production of the LED module board and the SMT production size of the chip mounter, the board size was determined considering the overall size of the product by model. In this paper, four 20W LED boards are arranged vertically in order to produce an 80W board. In other words, by sharing LED module board size by model, high power LED lighting equipments of 120W and 200W can be selected as an increase in the number of boards.

Characteristics of PECVD-W thin films deposited on $Si_3N_4$ ($Si_3N_4$상에 PECVD법으로 형성한 텅스텐 박막의 특성)

  • 이찬용;배성찬;최시영
    • Journal of the Korean Vacuum Society
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    • v.7 no.2
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    • pp.141-149
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    • 1998
  • The W thin films were deposited on Si3N4 by a PECVD technique. The effects of substrate temperature and gas flow ratio on the properties of the W films were investigated. The deposition of W films were limited by surface reaction at the temperature range of 150>~$250^{\circ}C$, W films had the deposition rate of 150~530 $\AA$/min and stress of 0.85~$14.35\times10 ^9 \textrm {dynes/cm}^2}$ at various substrate temperatures and $SiH_4/WF_6$ flow ratios. $SiH_4/WF_6$ flow ratio affected the deposition rate and stress of the W films, expecially, excessive flow of SiH4 abruptly changed the structure, chemical bonding, and stress of the W films. Among the deposited W films on TiN, Ti, Mo, NiCr and Al adhesion layer, the one on the Al had the best adhesion property.

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Characterization of tryptophan residues of human coagulation factor V required for binding to phospholipid membranes (인지질막 결합에 필요한 제5혈액응고인자 트립토판잔기들의 역할규명)

  • Kim, Suhng-Wook
    • Journal of Life Science
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    • v.13 no.4
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    • pp.463-472
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    • 2003
  • Interactions between factor Va (HFVa) and membrane phosphatidylserine (PS) regulate the activity of the prothrombinase complex. I have previously shown that two solvent exposed hydrophobic residues located in the C2-domain, Trp2063 and Trp2064, are required for binding to immobilized PS and for expression of procoagulant activity on membranes containing 5% PS. In order to fully define the functional importance of these two residues I have expressed and isolated recombinant factor Va (rHFVa) W2063A/W2064A double mutant. In contrast to the native protein the two glycoforms resulting from alternative glycosylation of Asn2181 eluted as a single peak with rHFVa1 W2063A/W2064A eluting on the leading edge and rHFVa2 W2063A/W2064A eluting on the trailing edge. The double mutant rHFVa2 W2063A/W2064A expressed little or no procoagulant activity on membranes containing 1-10% mol % PS. In contrast, the procoagulant activity of this mutant was slightly greater than the native protein on membranes containing>18 mol % PS. The binding of rHFVa2 W2063A/W2064A to immobilized phospholipid vesicles was markedly reduced compared to the native protein in a surface plasmon resonance binding assay. I conclude that Trp2063 and Trp2064 are required for high affinity binding of factor Va to PS membranes and that this interaction is necessary for assembly of the prothrombinase complex on membranes containing physiological concentrations of PS.

The Engineering Properties of Concrete Exposed at High Temperature (고온을 받은 콘크리트의 공학적 특성)

  • 권영진;김용로;장재봉;김무한
    • Fire Science and Engineering
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    • v.18 no.1
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    • pp.31-36
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    • 2004
  • The purpose of this study is to present data for the reusing, rehabilitation and estimation of safety of RC structure damaged by fire, and for the prevention of explosive spatting by investigation the properties of explosive spalling, compressive strength and ultrasonic pulse velocity according to kinds of fine aggregate, admixture and water-cement ratios. In explosive spalling properties with kinds of aggregate, explosive spalling does not appear or little at surface in the case of used sea sand, but the case of using recycled sand or crushed sand is worse and worse. Property with the kind of admixture does not appear specially. And high strength concrete with W/C 30.5% was taken spalling, but 55% does not appear. It is found that residual compressive strength after exposed at high temperature showed 45% in W/C 55%, and 64% in W/C 30.5% of its original strength averagely. Ultrasonic pulse velocity is different with kinds of aggregate. W/C. and heating time. When 3 month age after heating ultrasonic pulse velocity is recovered abut 1.3%~8.4% of its 1 month age after heating.

The Impact of Kinds of Dietary Grain and Dietary Lipid Level on the Glucose Metabolism and Antithrombogenic Capacity of Full Grown Obesity Induced Rats (식이 내 곡류 종류와 지방수준이 성장기 이후 비만유도 흰쥐의 당대사와 항혈전능에 미치는 영향)

  • Ok, Hyang-Mok;Sohn, Jung-Sook;Kim, Mi-Kyung
    • Journal of Nutrition and Health
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    • v.38 no.8
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    • pp.613-625
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    • 2005
  • This study was designed to evaluate impact of kinds of dietary grain and dietary lipid level on the glucose metabolism and antithrombogenic capacity in obesity induced rats. Total of 80 Sprague-Dawley male rats were raised for one month with control diet containing $50\%$ (w/w) well-milled rice powder and $20\%$(w/w) of dietary lipids. The rats were blocked into 8 groups and raised for two months with diets containing well-milled rice, brown rice, black rice, or glutinous barley powder and 8 or $20\%$(w/w) of dietary lipids. The contents of total dietary fiber in experimental grains were in following order; glutinous barley > black rice > brown rice > well-milled rice. Weekly food intake were lower in glutinous barley group among all experimental groups. Body weight gain was high in high level of fat groups ($50\%$w/w) than medium level of fat groups ($8\%$ w/w). Plasma glucose concentration was not different significantly in each groups. But brown rice group was a little lower than others. Plasma insulin concentration was lower in black rice and glutinous barley group than rice group. Plasma glucagon concentration did not differ significantly among all experimental groups. Hexokinase activities in skeletal muscle are different significantly according to level of dietary fat and grain variety factors. Brown rice group was significantly highest among all experimental groups in hexokinase activity. Plasma $TXB_2$ concentrations in black rice and glutinous barley groups were lower as compared to rice and brown rice groups. Plasma 6-keto-$PGF_{1\alpha}$ concentrations in glutinous barley group was higher as compared to others. In conclusion brown rice has a little lowering effect glucose concentration. Black rice and glutinous barley intakes enhance antithromboenic capacity. It is suggested that the intakes of mixed gains are recommend.

A Study on Performance Improvement of a PHC-W Pile for PHC-W Retaining Wall (PHC-W 흙막이용 PHC-W말뚝의 성능개선에 관한 연구)

  • Kim, Chae Min;Kim, Sung Su;Jeon, Byeong Han;Choi, Yongkyu
    • Journal of the Korean Geotechnical Society
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    • v.33 no.2
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    • pp.27-34
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    • 2017
  • Various earth retaining wall methods were used on the domestic construction sites and a cast in place pile (C.I.P) method was mostly applied at deep excavation. Because of a lot of shortcomings in the C.I.P method, a new method using PHC-W earth retaining wall was developed. The earth retaining wall method using PHC-W piles has a lot of advantages including that it is safer than other earth retaining wall methods due to uniform quality and high rigidity. PHC-W was designed to effectively resist lateral earth pressure by alternating cross section of PHC pile. And increment of bending moment and shear strength were verified through KS F 4306 tests, and were increased by 42% and 98% more than KS standards.

HyGIS based on cloud computing (클라우드 기반 HyGIS)

  • Won, Young Jin;Choi, Yun Seok
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.316-316
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    • 2016
  • HyGIS는 DEM 기반의 수문지형처리를 중심으로 다양한 모형을 연계할 수 있도록 구성된 S/W 모음이다. 이는 한국건설기술연구원을 비롯한 다수의 기관 및 연구원들이 노력한 성과물이다. 본 연구는 기존 HyGIS 연구과정에서 도출된 성과물의 실용화 사업화를 위한 방안을 연구하였다. 이를 위하여 S/W 테스팅, 오픈소스 도입, 클라우드 컴퓨팅으로 나누어 접근하였다. 먼저 S/W의 테스팅에 있어서 기존 개발 소스코드는 블랙박스 테스트 방식의 동등 클래스 분할, 경계 값 분석 등 일부 모듈에 대한 단위 테스트와 제한적인 통합테스트가 수행된 바 있다. 보다 체계적인 테스트 단계로서 화이트박스 테스트 개념 중 문장/분기/조건 커버리지에 대하여 검토하였으며, 실제 소스코드 중 핵심 구간에 대한 적용 및 정량화를 통하여 현 수준을 객관적으로 진단하였고 보완 방안을 도출하였다. 오픈소스 적용을 위하여 QGIS, MapWindow 등 공간정보 분야의 최신 오픈소스 모듈을 비교 검토하였다. 적용 단계는 이를 기존 HyGIS S/W에 반영시키는 과정이며, S/W 관점에서는 컴포넌트 모듈의 대체라고 표현될 수 있다. 대규모의 전환 비용이 발생되므로 적용 후보에 대하여는 기능적 측면 뿐만 아니라 마이그레이션 비용과 중장기적인 유지보수 비용을 고려한 검토가 이루어 졌다. 한편 오픈소스 기술의 적용은 단순히 구성 요소 원가절감 측면만이 아닌, 중장기적 유지보수 체계 도모 및 지속가능한 생태계로의 전환에 더 큰 의의가 있다. 마지막으로 클라우드 컴퓨팅 기술의 적용 분야이다. HyGIS 입력 Data의 공급을 위한 인프라로서 자체 구축 인프라가 아닌 IaaS 클라우드인 Blob Storage 및 CDN을 시험 적용하였다. 클라우드를 활용함으로써 초기 비용을 최소화하고 합리적 비용으로 유연한 확장이 가능한(Scale Out, Scale Up) 구조를 취하게 되었다. 또한 입력 Data 공급 서버를 위한 Storage 측면만이 아니라 S/W의 배포에 있어서도 클라우드 컴퓨팅 기술을 활용하고자 시도하였다. 클라우드 기술을 활용하여 HyGIS S/W가 설치된 VM(Virtual Machine)자체를 임대하는 방식으로 시험 구성 되었다. VM에 대한 RDP 프로토콜 Access에 있어서 IP기반 접근 제어를 통하여 보안을 강화하는 방안을 실험하였으며, ISO 27001, ISO 27018 등 관련 보안 규정에 부합하는 서비스 제공이 가능하도록 검토하였다. 이러한 클라우드 VM방식 서비스를 통하여 Package형 S/W 뿐만 아니라 Subscription 방식의 서비스 제공 방식을 병행할 수 있다. 사용자에게는 S/W 설치 및 H/W Lock 구비 과정이 생략되는 이점이 있다.

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Development of SSPA-based X-band Transmitter with Graceful Degradation (점진적 성능저하 기능을 가지는 X-대역 SSPA 송신장치 개발)

  • Song, Hyeong-Min;Kim, Ji-Deok;Kang, Hyun-Chul;Song, Jae-Gyeong;Park, Chul-Soon;Rhee, Kye-Jin;Lee, Choung-Hyun;Kim, Dong-Gil
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.5
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    • pp.853-862
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    • 2019
  • In this paper, we designed a 4.5kW X-band SSPA transmitter to replace the TWTA search radar transmitter with low MTBF and high maintenance cost. The transmitter is designed for the performance of over 520W average transmission output and 4.0kW maximum transmission output. In particular, by implementing a graceful degradation, it is designed to maintain better performance than conventional TWTA transmitter up to 40% (13 assembly modules) failure level of 200W power amplifier assembly. Through an experiment on the effective range of X-band, the performance of proposed transmitter verified the values of the maximum transmission output 6.1kW, spurious output 69.16dBc, RF pulse rising time 15.2ns and RF pulse falling time 16.3ns. The experiment confirmed the change of output power according to the graceful degradation due to fault injection.

Stability of W/O Nanoemulsions with Low Viscosity Prepared by PIC Method (PIC 방법으로 제조된 저점도 W/O 나노에멀젼의 안정성)

  • Cho, Wan Goo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.2
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    • pp.127-133
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    • 2016
  • In this study, water-in-oil (W/O) nanoemulsions of water/Span 80-Nikkol BL 25/oil system were prepared by the PIC method at elevated temperature. This method allows the formation of finely dispersed W/O nanoemulsions with low viscosity in this system. However, macroemulsions rather than nanoemulsions were prepared by PIC method at room temperature. As a result of the significant change of interfacial tension with temperature, the emulsion droplet size decreases from $2{\mu}m$ to 100 nm with the increase in temperature from $30^{\circ}C$ to $80^{\circ}C$. The droplet size of nanoemulsions prepared at $80^{\circ}C$ was in the range of 50 ~ 200 nm and the internal phase content could reach as high as 15 wt%. The most stable nanoemulsion was formed in the vicinity of 7.0 of optimum HLB of the emulsifier mixture. The obtained nanoemulsions were stable without obvious change in droplet size in one month. This study provides valuable information for optimizing the formation of W/O nanoemulsions with low viscosity. These results suggest that W/O nanoemulsions of low viscosity could be useful for cosmetics with soft feeling.