• Title/Summary/Keyword: A/W

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Effects of Security Lighting Lamps on Discomfort Glare to Indoor Occupants

  • Lee, Yoon Jeong;Kim, Jeong Tai
    • KIEAE Journal
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    • v.15 no.4
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    • pp.21-28
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    • 2015
  • Purpose: Although security lights are used to secure pedestrian visibility and safety at nighttime, they can generate light trespass in the neighboring residential space. To prevent this, standards for acceptance limits on vertical illuminance and light pollution by the windows of residential buildings are presented. Method: This study thus representatively selected three types of lamps and, through an evaluation and analysis of the physical and subjective discomfort glare per lamp, proposed a discomfort glare index for each lamp. The evaluation and analysis according to the lamps were conducted through experiments. The variables were the security lights' lamps (NH 100W, MH 70W, LED 50W), installation angles ($0^{\circ}$, $20^{\circ}$), and installation distances (3m, 5m, 7m, 9m). Result: According to the results of the discomfort glare evaluation depending on the angles and distances of the security lights, the following minimum standards are proposed: for NH 100W, a discomfort glare index of 30 and an installation distance of 4m; for MH 70W, a discomfort glare index of 32 and an installation distance of 4m; and, for LED 50W, a discomfort glare index of 31 and an installation distance of 6m, respectively. In addition, this paper recommends the use of MH 70W, when the road width is 4m-6m, and LED 50W, when the road width is over 6m, respectively.

The effect of osmotic pressure in W/O/W multiple emulsion (다상 에멀전 형성에 있어 삼투 현상이 미치는 영향)

  • 신중진;이근수;강기춘;표형배
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.26 no.1
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    • pp.139-148
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    • 2000
  • The osmotic pressure is a one of the most important factor affecting stabilization of multiple emulsion in a law hours after experiment. To understand and decrease osmotic pressure between Wl phase and W2 phase, a kinds of humectants were introduced in outer water phase. As a result, Betaine and Glucose had an excellent effect reducing osmotic pressure and NaCl made W/O/W emulsion more stable than MgSO4 did when introduced in inner water phase.

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A Study on the Fabrication and Characteristics of Continuous W-Cu FGM by Spark Plasma Sintering (방전플라즈마소결법에 의한 W-Cu 연속경사기능재료의 제조와 특성에 관한 연구)

  • 신철균;강태훈;권영순;김지순;김환태;석명진
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.03a
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    • pp.217-217
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    • 2003
  • W-Cu 합금은 우수한 전기적, 열적 특성으로 인하여 열소산재료(Heat sink)로 많이 응용되고 있다. 첨단 전자부품 이외에도 핵융합로의 Diverter가 그 예로서, 내부는 고강도와 고융점의 특성을 요구하는 반면, 외부는 높은 열전도성을 필요로 한다. 그래서 동일한 조성의 일반적인 W-Cu 합금보다 W과 Cu의 조성이 점차적으로 변화하는 경사기능재료(Functionally Graded Materials)가 냉각효율이 클 것으로 기대된다. 현재, W-Cu FGM에 대한 많은 연구가 진행되고 있지만, 그 조성이 연속적으로 변화하는 W-Cu FGM에 대한 연구는 전무한 실정이다 본 연구에서는 방전플라즈마 소결장치(Spark Plasma Sintering System)와 용침고정을 이용하여 연속적인 조성변화를 갖는 W-Cu FGM을 제조하고 그 특성에 관해 분석하고자 하였다. 소결체가 밀도 변화를 갖게 되도록 제작한 특수 경사기능 몰드에 W분말을 장입한 후, 15㎬의 압력하에서 SPS를 이용하여 W소결체를 제조하였다. 제조된 W소결체는 수평관상로에서 수소분위기 하에 Cu 용침을 실시하여 W-Cu FGM을 제조하였다 SEM을 이용한 각 위치별 조직관찰과 Image Analyzer를 이용한 W과 Cu의 면적비, 그리고 비커스경도계에 의한 경도 측정을 실시하였다. 또 열기계적 분석기를 이용하여 측정된 선팽창률로부터 열팽창계수를 구하였다. 80$0^{\circ}C$에서 ?칭하는 반복적인 싸이클을 통해 열충격시험을 실시하였고, Laser flash method로 열확산계수를 측정하였다.

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A case study on programming academic achievement: Focused on the hardware curriculum (프로그래밍 학업성취도에 관한 사례연구: 하드웨어 교과과정 중심으로)

  • Lee, Seung-Woo
    • Journal of the Korean Data and Information Science Society
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    • v.25 no.4
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    • pp.779-790
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    • 2014
  • The purpose of this study is to find the programming capability for the students majoring in H/W. For implementing this purpose, first, the academic achievements on the C language and C++ language are measured for the graduates-to-be majoring in H/W and S/W. Second, the H/W and S/W curriculum are compared and analyzed to derive the relevant factors to give influence on the academic achievement of the programming. Third, to find the influence of mathematic competence on the academic achievement of the programming, the relevance is analyzed in terms of the regression analyses between mathematics curriculum and programing curriculum. This paper presents the effective teaching method for the improvement of the programming academic achievement in the H/W curriculum.

Fabrication of W-10wt.%Cu Powder for the Application of Metal Injection Molding (금속사출성형을 위한 W-10wt.%Cu 분말의 제조에 관한 연구)

  • 김순욱;손찬현;김영도;문인형
    • Journal of Powder Materials
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    • v.8 no.4
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    • pp.245-252
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    • 2001
  • Recent remarkable progress in the semiconductor industry has promoted smaller size of semiconductor chips and increased amounts of heat generation. So, the demand for a substrate material to meet both the characteristics of thermal expansion coefficient and heat radiation has been on the increase. Under such conditions, tungsten(W)-copper(Cu) has been proposed as materials to meet both of the above characteristics. In the present study, the W-10wt.%Cu powders were synthesised by the mixing and hydrogen reduction of the starting mixture materials such as W-Cu, $W-CuCl_2$and $WO_3-CuCl_2$ in order to obtain the full densification. The W-10wt.%Cu produced by hydrogen reduction showed the higher interparticle friction than the simple mixed W-10wt%Cu because of the W agglomerates. In the dilatometric analysis the W-10wt.%Cu prepared from the $W-CuCl_2$was largely shrank by heating up $1400^{\circ}C$ at the constant heating rate of $5^{\circ}C$/min. The possibility of application of metal injection molding (MIM) was also investigated for mass production of the complex shaped W-Cu parts in semiconductor devices. The relationship between the temperature of molding die and the pressure of injection molding was analyzed and the heating up stage of 120-$290^{\circ}C$ in the debinding process was controlled for the most suitable MIM condition.

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A Study on the Hydrated and Dehydrated $Mn^{2+}$-Exchanged Zeolite A ($Mn^{2+}$-치환 제올라이트 A 의 수화 및 탈수 구조에 관한 연구)

  • Jong Yul Park;Yang Kim;Un Sik Kim;Sang Gu Choi
    • Journal of the Korean Chemical Society
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    • v.33 no.6
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    • pp.623-632
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    • 1989
  • The positions and interaction energies of framework atoms and water molecules of $Mn^{2+}$-exchanged zeolite A were calculated using some potential energy functions and an optimization program. The sum of interaction energies of framework atoms in dehydrated $Mn_{4,5}Na_3-A$ was approximately the same as those of thermally stable $Ca^{2+}$-or $Mg^{2+}$-exchanged zeolite A. Since $Mn^{2+}$ ions can form good coordination bonds with framework oxygens even in dehydrated state, $Mn^{2+}$-exchanged zeolite A is considered to be thermally stable. The optimized positions of framework atoms and ions in this work are agreed well with the crystallographic data. Three groups of water molecules are found in hydrated $Mn^{2+}$-exchanged zeolite A; W(I) group of water molecules having only hydrogen bonds, W(II) group coordinated to $Na^+$ ion, and W(III) group coordinated to $Mn^{2+}$ ion. The average binding energy of each group of water molecules decrease in the order of W(III) > W(II) > W(I). The activation energies in the dehydration reaction of each group of water molecules increased in accordance with their binding energy.

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Shrink-Resist Effects and Properties of the Knitted Fabrics from Wool/Acrylic Fiber Blends (양모/아크릴 혼방사 편성물의 방축 효과 및 물성에 관한 연구)

  • Lee Youn-Hee;Kwak Soo Kyoung;Park Myung-Ja
    • The Research Journal of the Costume Culture
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    • v.12 no.6 s.53
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    • pp.945-952
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    • 2004
  • Shrink-resist effects and properties of the knitted fabrics from wool/acrylic(W/A) fiber blends were determined to find out an optimal blending ratio keeping the quality properties of wool products. The test fabrics were knitted by a weft knitting machine with all needle knitting structure ($0{\times}0$ rib) under the same knitting conditions with five different types of yarns: $W100\%,\;A100\%$, and W/A blended yarns(70/30, 50/50, 30/70). Shrinkage during repeated washing, electrostatic propensity, thermal resistance and pilling propensity of W/A knits. The shrink resistance was significantly enhanced on repeated washing of W/A knits, especially, over $50\%$ acrylic blended knits. Addition of strong physical force and alkali detergent applied in this washing experiment brought about superior effects with the low shrinkage rate although it was very severe washing conditions for wool fabrics. The results from the washing experiment implies that W/A blend knits can be machine washed at individual households with other ordinary laundry. There was some changes and variation found in thermal resistance, electrostatic propensity, and pilling. W/A 50/50 blended knits did not bring serious changes to other physical properties comparing with original wool, which helps consumers care wool knitted clothes more conveniently.

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Effect of Double Replacement of L-Pro, D-Pro, D-Leu or Nleu in Hydrophobic Face of Amphipathic α-Helical Model Antimicrobial Peptide on Structure, Cell Selectivity and Mechanism of Action

  • Shin, Song Yub
    • Bulletin of the Korean Chemical Society
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    • v.35 no.11
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    • pp.3267-3274
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    • 2014
  • In order to investigate the effects of the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu (the peptoid residue for Leu) in the hydrophobic face (positions 9 and 13) of amphipathic ${\alpha}$-helical non-cell-selective antimicrobial peptide $L_8K_9W_1$ on the structure, cell selectivity and mechanism of action, we synthesized a series of $L_8K_9W_1$ analogs with double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu in the hydrophobic face of $L_8K_9W_1$. In this study, we have confirmed that the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, or Nleu in the hydrophobic face of $L_8K_9W_1$ let to a great increase in the selectivity toward bacterial cells and a complete destruction of ${\alpha}$-helical structure. Interestingly, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu preferentially interacted with negatively charged phospholipids, but unlike $L_8K_9W_1$ and $L_8K_9W_1$-$\small{D}$-Leu, they did not disrupt the integrity of lipid bilayers and depolarize the bacterial cytoplasmic membrane. These results suggested that the mode of action of $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu involves the intracellular target other than the bacterial membrane. In particular, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu had powerful antimicrobial activity (MIC range, 1 to $4{\mu}M$) against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Taken together, our results suggested that $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu with great cell selectivity may be promising candidates for novel therapeutic agents, complementing conventional antibiotic therapies to combat pathogenic microorganisms.

A Design for URC Robot S/W Platform (URC 로봇 소프트웨어 플랫폼 설계)

  • Im, Sung-Ho;Kwon, Kee-Koo;Lim, Dong-Sun;Kim, Sung-Jung
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.252-254
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    • 2005
  • In this paper, we present a design for URC (Ubiquitous Robotics Companion) robot S/W platform. The URC robot S/W platform is based on the Qplus/Esto which is developing in ETRI and applied for URC robot reference S/W platform that we use it in case of many different robots with same interface. We expect the platform to save the developing time, to improve the compatibility and to reuse the developed contents.

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Np-SPACES

  • Kim, Yun-Su
    • Journal of the Korean Mathematical Society
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    • v.48 no.5
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    • pp.1043-1052
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    • 2011
  • We introduce a new norm, called the $N^p$-norm (1 $\leq$ p < ${\infty}$ on the space $N^p$(V,W) where V and W are abstract operator spaces. By proving some fundamental properties of the space $N^p$(V,W), we also discover that if W is complete, then the space $N^p$(V,W) is also a Banach space with respect to this norm for 1 $\leq$ p < ${\infty}$.