• 제목/요약/키워드: Different sources

검색결과 3,408건 처리시간 0.033초

다양한 화원으로부터 발생된 연기를 감지하는 광전식연기감지기의 필요성에 대한연구 (A Study on the Need for Developing a Photoelectric Smoke Detector Detecting Smokes Emitted from Diverse Fire Sources)

  • 이종화
    • 대한안전경영과학회지
    • /
    • 제18권1호
    • /
    • pp.65-73
    • /
    • 2016
  • In this paper which was performed to bring public attention to the need for developing an photoelectric smoke detector that detects smokes emitted from diverse fire sources, it was confirmed that the photoelectric smoke detector may not respond to certain smoke types depending on the size and color of smoke particles. The test was performed on a photoelectric smoke detector which is being used generally for specific fire targets specified in UL268, including paper fire, wood fire and flammable liquid fire, while the actual response performance of the fire detector, as well as respective smoke particles collected from different fire source which were photographed with a SEM(Scanning electron microscope) were analyzed in the test for this study.

전문직 여성들의 의복 구매 행동에 관한 연구 (A Study on Career Women′s Clothing Purchase Behavior)

  • 구양숙;박금주
    • 복식문화연구
    • /
    • 제6권1호
    • /
    • pp.71-83
    • /
    • 1998
  • The purpose of this study was to classify career women's apparel shopper type by analyzing clothing shopping orientations and to compare the classified shopper types on store evaluative criteria, information sources, and demographic characteristics. The questionnaire was administered to 328 career women aged 20∼59 years. The data were analyzed using factor analysis, cluster analysis, ANOVA, MONAVA, and x² test. The results of this study were as follows: Eight factors of clothing shopping orientation derived by factor analysis. Four shopper types were classified by cluster analysis: Apathetic shopper, High shopping involved shopper, Conformable shopper, Economic shopper type. Store evaluative criteria, information sources and demographic characteristics were significantly different among four shopper types.

  • PDF

Effect of Ag Powder Sources on the Patterning of PDP Electrodes

  • Woo, Chang-Min;Kim, Soon-Hak;Hur, Young-June;Kim, Duck-Gon;Song, Gab-Duk;Lee, Yoon-Soo;Cho, Ho-Young;Park, Lee-Soon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
    • /
    • pp.953-955
    • /
    • 2006
  • In this work we compared different sources of composition of Ag powders obtained by dry and wet process on the photolithographic patterning of PDP electrode and resistance of sintered Ag electrode. It was found that 90 : 10 wt% ratio of Ag powder made by dry and wet processes gave optimum result both on the PDP electrode pattern and resistance of PDP electrode after sintering.

  • PDF

양전원전압병용단상전동기의 권선설계의 조정에 관한 고찰 (Analysis on Arrangements of Winding Design of Single-Phase Capacitor Motor Used to Two Voltages)

  • 황영문;이일천
    • 전기의세계
    • /
    • 제28권3호
    • /
    • pp.65-71
    • /
    • 1979
  • This paper examines the reasonable winding arrangements of designing tapped winding capacitor motors to used in two voltage sources. The approach of this paper is based partly on a hybrid equivalent circuit of a single phase induction motor, together with an experimental method by sample machines. In results, the distribution of etra and main windings ia the stator is to be balanced in each magnetic pole and in order to have the same torque output characteristics for two different voltage sources, the extra/main winding ratio is to be adjusted. Experimental results obtaired with sample macines of about 1/8 hp output rating are used with analysis to predict the favorable winding conditions.

  • PDF

Marine-Derived Pharmaceuticals - Challenges and Opportunities

  • Lindequist, Ulrike
    • Biomolecules & Therapeutics
    • /
    • 제24권6호
    • /
    • pp.561-571
    • /
    • 2016
  • Marine biosphere is the largest one of the earth and harbors an enormous number of different organisms. Living conditions differ fundamentally from those in terrestrial environment. The production of specific secondary metabolites is an important adaption mechanism of marine organisms to survive in the sea. These metabolites possess biological activities which make them interesting as possible drugs for human. The review presents sources, chemistry, production and pharmacology of FDA approved marine derived pharmaceuticals arranged according to their therapeutic indication. Four of the presently seven approved drugs are used for the treatment of cancer. Each another one is applicated for treatment of viral diseases, chronic pain and to lower triglyceride level in blood. Some other products are of interest in diagnostic and as experimental tools. Besides, this article describes challenges in drug development from marine sources, especially the supply problem.

한국형 고속철도의 소음/진동 특성에 관한 연구 (A Study on Characteristics of Noise and Vibration for KTX)

  • 김재철;구동회;문경호
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2001년도 춘계학술대회논문집
    • /
    • pp.829-835
    • /
    • 2001
  • The sources of wayside noise for the high speed train are the aerodynamic noise, rolling noise and power unit noise. One of the best ways to control the wayside noise is to analysis the noise level. In this paper, we measure the wayside noise and the vibration of the rail/sleeper for Korean Train Express (KTX) and compare with the results for the conventional train. The measurement results for KTX show that the characteristics of the noise and vibration are different from the conventional train and the rolling noise and power unit noise are the major sources.

  • PDF

헬리콥터 로터 블레이드의 자려소음 예측 (Self-Noise Prediction from Helicopter Rotor Blade)

  • 김효영;유기완
    • 항공우주시스템공학회지
    • /
    • 제1권1호
    • /
    • pp.73-78
    • /
    • 2007
  • Self-noise from the rotor blade of the UH-1H Helicopter is obtained numerically by using the Brooks' empirical noise model. All of the five noise sources are compared with each other in frequency domain. From the calculated results the bluntness noise reveals dominant noise sources at small angel of attack, whereas the separation noise shows main noise term with gradually increasing angel of attack. From the results of two different tip Mach numbers with the change of angel of attack, the OASPLs at M = 0.8 show about 15dB larger than those at M = 0.4.

  • PDF

개구리밥과 식물의 질소대사에 관한 연구: 개구리밥(Spirodela polyrhiza)과 좀개구리밥(Lemna aequinoctialis)의 NO3-와 NH4-의 동화작용 (A Study on Nitrogen Metabolism of Lemnaceae: Assimilation of Nitrate and Ammonia in Spirodela polyrhiza and Lemna aequinoctialis)

  • 장남기
    • Journal of Plant Biology
    • /
    • 제34권4호
    • /
    • pp.253-260
    • /
    • 1991
  • Spirodela polyrhiza and Lemna aequinoctialis often occurred at the sites of high ammonium concentration and at the sites of high nitrate concentration, respectively. We investigated the different distribution between two species in relation to the type of nitrogen sources and their concentrations. Our experiments showed that L. aequinoctialis grew faster than S. polyrhiza in nitrate media with lower than 15 mM concentration. The nitrate uptake was also faster in L. aequinoctialis than in S. polyrhiza. However, neither differences in growth nor in uptake patterns between these two species were observed in ammonium media. Glutamine synthetase (GS), glutamate dehydrogenase (GDH) and glutamate synthetase (GOGAT) activities were higher in L. aequinoctialis. In particular, nitrate reductase activity (NRA) in L. aequinoctialis was 12.1 times as high as that in S. polyrhiza. These results showed that the two species responded varyingly to the types of nitrogen sources and their concentrations. Therefore, the difference in geographic distribution between the two species appeared to reflect the interspecific differences in enzyme activities and, subsequently, nitrogen absorption abilities.

  • PDF

Toward a Self-Consistent Simulation of the Cosmic Reionization

  • 안경진
    • 천문학회보
    • /
    • 제35권1호
    • /
    • pp.78.2-78.2
    • /
    • 2010
  • Ionization of hydrogen occurs globally in our universe. The epoch of this cosmic reionization may be probed by various observations, among which the 21cm observation of neutral hydrogen at high redshift is the most promising candidate. In order to provide a mock data, we have performed the first, self-consistent simulation of cosmic reionization. We account for all possible UV-radiating sources which reside in halos ranging from minihalos to atomically-cooling halos. In order to simulate the contribution from Pop III objects, we also calculate the radiative transfer of Lyman-Werner radiation and apply a suppression criterion for Pop III objects. Our priliminary result indicates that Pop III objects ionize the universe at very high redshift and create rich, small-scale bubble structure, while sources in atomically-cooling halos ionize the universe at relatively low redshift and create large-scale bubble structure. We discuss how these two different scales and epoch may be probed by future 21cm observations.

  • PDF

Formation of short-period black hole binary systems from Population III stars as grativational wave radiation sources

  • Lee, Hunchul;Yoon, Sung-Chul
    • 천문학회보
    • /
    • 제42권1호
    • /
    • pp.59.1-59.1
    • /
    • 2017
  • Massive Population III black hole binary systems are one of the suggested candidate sources of the recently detected gravitational wave radiation (GWR). GWR detection from a black hole binary system requires a sufficiently short orbital separation at the time of their formation, such that they would undergo coalescence within the Hubble time. This condition cannot be simply fulfilled by a short initial period, because binary interactions such as mass transfer and common envelope evolution can largely change the orbital parameters and the masses of stellar components. Here, we discuss the possibility of black hole binary mergers from massive Pop III binary systems, using a new grid of Pop III binary evolutionary models with various initial primary masses ($20M_{\odot}{\leq}M{\leq}100M_{\odot}$) and initial separations, for different initial mass ratios (q = 0.5 - 0.9).

  • PDF