• 제목/요약/키워드: H&R

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엘리베이터용 정전시 비상구출장치에 관한 연구 (A study of ALP for elevator)

  • 장철호;이근호;허재영;이정규;김한종;최창식;정종태
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 F
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    • pp.2013-2015
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    • 1997
  • Elevator stops emergently when power failures happen during operation. In that case, the passenger should wait with frightened in the car untill they are rescued by repair man or power resumes. This paper describes an automatic landing device for power-failure(ALP) that consists of UPS and battery charge control system. The excellence of the ALP operation is verified by experiments in elevator test tower.

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BOUNDEDNESS AND INVERSION PROPERTIES OF CERTAIN CONVOLUTION TRANSFORMS

  • Yakubovich, Semyon-B.
    • 대한수학회지
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    • 제40권6호
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    • pp.999-1014
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    • 2003
  • For a fixed function h we deal with a class of convolution transforms $f\;{\rightarrow}\;f\;*\;h$, where $(f\;*\;h)(x)\;=\frac{1}{2x}\;{\int_{{R_{+}}^2}}^{e^1{\frac{1}{2}}(x\frac{u^2+y^2}{uy}+\frac{yu}{x})}\;f(u)h(y)dudy,\;x\;\in\;R_{+}$ as integral operators $L_p(R_{+};xdx)\;\rightarrow\;L_r(R_{+};xdx),\;p,\;r\;{\geq}\;1$. The Young type inequality is proved. Boundedness properties are investigated. Certain examples of these operators are considered and inversion formulas in $L_2(R_{+};xdx)$ are obtained.

High Performance OCB Panel Driven less than 5V for Multi-media Application

  • Chang, H.S.;Lee, C.H.;Ryu, J.J.;Kim, M.S.;Ahn, S.H.;Kim, K.H.;Kim, S.S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.914-917
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    • 2002
  • We have obtained high performance and low voltage driving OCB panel by reducing the critical voltage and retardation matching between liquid crystal layer and compensation films. The critical voltage in the panel has been minimized by flattening color filter layer and optimizing a rubbing process. In addition, an appropriate retardation of the film and LC layer has scanned to achieve low driving voltage and high transmission. The proto-type 17" WXGA OCB panel has demonstrated with less than 5V drive and over 80 degree for all viewing direction except for rubbing direction with over 90% of TN light efficiency.

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전역 최적화 기법 소개 : 결정론적 및 확률론적 방법들

  • 최수형
    • 제어로봇시스템학회지
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    • 제10권3호
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    • pp.27-33
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    • 2004
  • 최적화는 시스템공학에서 자주 등장하는 문제이며 흔히 다음과 같은 수학적 계획(mathematical programming) 문제로 표현된다. min f(x) (P) subject to g(x) ≤ 0 h(x) : 0 여기서 x∈R/sup n/, f:R/sup n/→R, g:R/sup n/→R/sup l/, h:R/sup n/→R/sup m/, 그리고 n m이다. 만약 목적함수(objective function)와 가능 영역(feasible region)이 볼록(convex)하다면, 예를 틀어 f(x)와 g(x)가 아래로 볼록하고 h(x)가 선형이라면. 이는 볼록 문제(convex problem)이며 오직 하나의 지역 최소점(local minimum)을 가진다. 그러나 많은 경우. 예를 들어 h(x)가 비선형이라면, 여러 개의 지역 최소점을 가질 수 있는 비 볼록 문제(nonconvex problem)가 된다. 이때 진정한 최소점을 찾는 것. 즉 전역 최적화 (global optimization)가 요구된다.(중략)

On the Local Cohomology and Formal Local Cohomology Modules

  • Shahram Rezaei;Behruz Sadeghi
    • Kyungpook Mathematical Journal
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    • 제63권1호
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    • pp.37-43
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    • 2023
  • Let 𝔞 and 𝔟 be ideals of a commutative Noetherian ring R and M be a finitely generated R-module of dimension d > 0. We prove some results concerning the top local cohomology and top formal local cohomology modules. Among other things, we determine SuppR(𝔟 Hd𝔞(M)) and SuppR(𝔟𝔉d𝔞(M)). Also, we obtain some relations between AnnR(𝔟 Hd𝔞(M)), AttR(𝔟 Hd𝔞(M)) and SuppR(𝔟 Hd𝔞(M)) and we get similar results for 𝔟𝔉d𝔞(M).

야산(野山) 목초지용(牧草地用) 내산성(耐酸性) 우수(優秀) 질소고정균주(窒素固定菌株) 개발(開發) -I. 영남지방(嶺南地方) 목야지(牧野地) 근류균(根瘤菌)의 내산성정도(耐酸性程度) (Studies on the Development of Acid Tolerant and Superior Nitrogen Fixation Symbionts for Pasture on Hilly Land -I. The Degrees of Acid Tolerance of Rhizobia from the Pastures in Yeongnam Area)

  • 강위금;최주현;조강진;정연태;이재생
    • 한국토양비료학회지
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    • 제20권4호
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    • pp.369-374
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    • 1987
  • 우량(優良) 질소고정균주(窒素固定菌株)를 개발(開發)하여 척박(瘠薄)한 야산(野山) 개발지(開發地)에서 효율적(效率的)인 초지조성(草地造成)을 꾀하고자, 영남지역(嶺南地域) 목초지(牧草地) 근류균(根瘤菌)의 내산성(耐酸性) 정도(程度)를 시험(試驗)한 결과(結果)는 다음과 같았다. 1. 분리균주(分離菌株)의 내성산도(耐性酸度)는 R. meliloti의 경우(境遇) pH 4.3~5.5, R. trifolii에서는 pH 4.0~5.5 범위(範圍)이였음. 2. 내산성(耐酸性)이 큰 R. meliloti M3 및 M4와 R. trifolii T27, T30, T31, T33 균주(菌株)는 숙주접종(宿主接種)으로 근류(根瘤)를 형성(形成)하였고 질소고정력(窒素固定力)도 있었다. 3. 우리나라 야산(野山)의 평균산도(平均酸度)인 pH 4.8~5.0에서의 내산성(耐酸性) 균주(菌株)는 R. trifolii는 80~99%였으나 R. meliloti는 35~47%에 지나지 않으므로 보다 내산성(耐酸性)이 큰 R. meliloti의 선발(選拔)이 요구(要求)됨.

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다공성 Cr2O3 나노육각기둥을 이용한 C2H5OH 센서 (C2H5OH Sensor Using Porous Cr2O3 Nano-Hexaprisms)

  • 정현묵;이종흔
    • 센서학회지
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    • 제21권6호
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    • pp.451-455
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    • 2012
  • Dense Cr-precursor nano-hexaprisms were prepared by heating the Cr-nitrate aqueous solution containing Hexamethylenetetramine and polyvinylpyrrolidone, which were converted into porous $Cr_2O_3$ nano-hexaprisms containing nanoparticles by heat treatment of Cr-precursors at $600^{\circ}C$ for 2 h in air atmosphere. At the sensor temperature of $300^{\circ}C$, porous $Cr_2O_3$ nano-hexaprism showed the high response ($R_g/R_a$, $R_g$: resistance in gas, $R_a$: resistance in air) to 100 ppm $C_2H_5OH$ ($R_g/R_a=69.8$) with negligible cross-responses to 100 ppm CO and 5 ppm $C_6H_6$. The sensitive and selective detection of $C_2H_5OH$ in porous $Cr_2O_3$ nano-hexaprism were discussed in relation to the morphology of nanostructures.

미국자리공(Phytolacca americana L.) 뿌리의 항균 펩타이드 정제 및 특성연구 (Purification and Charaterization of Antimicrobial Peptide from Roots of Pokeweed)

  • 김정주;장혜영;김재호
    • Applied Biological Chemistry
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    • 제46권4호
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    • pp.385-390
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    • 2003
  • 미국자리공(Phytolacca americana L.) 뿌리에서 항균 펩타이드를 분리하여 PAMP-r로 명명 하였다. 분리는 DEAE-cellulose, sephadex G-75, Mono S, Resource RPC등을 거쳐 이루어 졌으며 최종산물은 15% SDS-PAGE 에서 약 4,900 Da의 분자량을 보였다. PAMP-r는 광범위한 항균활성을 나타냈으며 온도와 pH변화에도 높은 안정성을 보였다. 항균활성은 $80^{\circ}C$에서 30분동안 유지될 뿐만 아니라 pH도 3.0의 산성에서부터 pH 8.0의 알카리에 이르기까지 광범위한 범위 안에서 안정하게 나타났다.

만성 뇌졸중 시 반복경두개자기자극에 의한 경직성 발목관절의 관절가동 범위 향상 및 H-반사 억제 효과 (The Effect of Repetitive Transcranial Magnetic Stimulation on H-Reflex Inhibition and Fascilitation of Range of Motion of Spastic Ankle Joint in Chronic Stroke Patients)

  • 조미숙
    • 대한물리의학회지
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    • 제6권1호
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    • pp.71-79
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    • 2011
  • Purpose : The purpose of this study was carried out to investigate the effect of repetitive transcranial magnetic stimulation on increase of H-reflex inhibition and fascilitation of range of motion of spastic ankle joint in chronic stroke patients. Methods : 30 chronic stroke patients were randomly divided into three groups, a control group(placebo rTMS group), 5 Hz rTMS group and manual therapy group. The MAS and ROM of ankle joint and H-reflex inhibition of soleus muscle were evaluated on each group. Results : The rTMS group decreased MAS of ankle joint and increased H-reflex inhibition of soleus muscle, and ROM of ankle joint than manual therapy group. The placebo rTMS group did not affected the change of MAS, ROM of ankle joint and H-reflex inhibition of soleus muscle. Conclusion : The rTMS was a good therapeutic tool to improve the foot drop in the chronic stroke patients.

아미노산을 이용한 망간 산화물 기공성 나노 구조의 합성 및 C3H8 가스에 대한 선택적 감응 특성 (Preparation of Manganese Oxide Porous Nanostructures using Amino-acid and its Selective C3H8 Sensing Properties)

  • 최권일;이종흔
    • 센서학회지
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    • 제20권1호
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    • pp.64-69
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    • 2011
  • Porous manganese oxide porous nanostructures were prepared by amino-acid-mediated solvothermal self assembly reaction and subsequent heat treatment at $600^{\circ}C$. When Mn-precursors were heat-treated at $400-550^{\circ}C$, the sensors did not show significant gas responses. In contrast, the manganese oxide heat-treated at $600^{\circ}C$ showed the significant gas responses, that is, the resistance decrease to 100 ppm $C_3H_8$ ($R_a/R_g$ = 2.17, $R_a$ : resistance in air, $R_g$ : resistance in gas) and the resistance increase to 100 ppm $C_2H_5OH$ ($R_g/R_a$ = 1.92). The opposite change of resistance upon exposure to $C_3H_8$ and $C_2H_5OH$ was discussed in relation to the mixed phases of manganese oxides with different valences.