• Title/Summary/Keyword: varied-intensity

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Perception of Public Safety of Night Users in Neighborhood Parks (도시공원 야간이용의 공공안전성 제고를 위한 요인 정합성 평가)

  • Rho, Jae-Hyun;Huh, Joon;Ahn, Deug-Soo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.23 no.2
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    • pp.213-222
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    • 1995
  • To increase the night use level, this study was analyzed perception of users about the public safety, and extracted main variables which were influencing public safety. The public safety was evaluated by the actual (on site) and nonactual users (off site) and the Delphi method. The night users of female and the elders were relatively more than male and the young respectively as compared with day. Walking was predominant in approaching means. In public safety ratings, $\boxDr$vuknerability to violence$\boxUl$varied accoding to sex, income, education, marriage, job, age. $\boxDr$crowding, $\boxDr$noise$\boxUl$ were important variables in satisfying users at night. $\boxDr$Lack of surveillance, $\boxDr$harassment of other person$\boxUl$, $\boxDr$rowdy behavior in poorer visibility$\boxUl$, $\boxDr$fear in lower intensity of light$\boxUl$ and $\boxDr$vulnerability to violence$\boxUl$stood high , so it is required guarantee of security guard to enhance the park use at night Although the ratings between field and indoor evaluation were somewhat different the variables had so similiar rant.

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Electrical Properties of Organic Photovoltaic Cell using CuPc/$C_{60}$ double layer (CuPc/$C_{60}$ 이중층을 이용한 유기 광기전 소자의 전기적 특성)

  • Lee, Ho-Shik;Cheon, Min-Woo;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.505-506
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    • 2007
  • Organic photovoltaic effects were studied in a device structure of ITO/CuPc/Al and ITO/CuPc/$C_{60}$/BCP/Al. A thickness of CuPc layer was varied from 10 nm to 50 nm, we have obtained that the optimum CuPc layer thickness is around 40 nm from the analysis of the current density-voltage characteristics in CuPc single layer photovoltaic cell. From the thickness-dependent photovoltaic effects in CuPc/$C_{60}$ heterojunction devices, higher power conversion efficiency was obtained in ITO/20nm CuPc/40nm $C_{60}$/Al, which has a thickness ratio (CuPc/$C_{60}$) of 1:2 rather than 1:1 or 1:3. Light intensity on the device was measured by calibrated Si-photodiode and radiometer/photometer of International Light Inc(IL 14004).

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A Comparative Study on the Sound Insulation Characteristics of Laminated Glass in Accordance with Material and Composition of Interlayer Film (Interlayer film 재료 및 구성에 따른 접합유리 차음성능 비교)

  • Hong, Jiyoung;Ko, Sangwon;Koh, Hyo-In;Jang, Seungho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2013.10a
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    • pp.501-505
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    • 2013
  • It is well known that monolithic glass has specific coincidence dip allowing transmittance of noise around the critical frequency. Laminated glass, made of a polyvinyle butyral(PVB) interlayer sandwiched by two panes of glass sheet, has long served for the advantage in noise attenuation properties as well as the safety purpose. More research on the improvement of sound insulation performance is needed, considering much of the noise is still transmitted through the glass. As a preliminary study, authors have made several test specimens, varied combinations of glass and interlayer film, to optimize the acoustic performance. Experimental investigation was carried out to study the sound transmission loss of test specimens in the reverberation chamber by using sound intensity method. Several new applications, instead of the existing PVB laminated glass, show better results in sound transmission loss and low temperature have a bad influence on the acoustic performance.

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An Experimental Study on the Swirling Flow Field in the Tangentially Fired Furnace (접선식 배치로내의 선회유동장에 관한 실험적 연구)

  • ;;;Yoon, S. H.;Sim, J. K.;Song, H. B.
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.11
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    • pp.3003-3013
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    • 1995
  • The characteristics of the flow field in the tangentially fired furnace are presented. Experiments are conducted in the simplified cold type isothermal flow model. In the measurement of flow field, a hot wire anemometer is used. The hot wire was calibrated by lookup table method. The mean velocity field and turbulence characteristics are showed with changing the nozzle angle. In the center of the model, the low speed, unstable flow region is formed. The size and position of these regions are varied with changing the nozzle angle. It can be used as fundamental data in the design of the large furnace. From the experimental results, various turbulent characteristics of swirling flow field is obtained. And the entrainment mechanism of the jet flow field is described from the distribution of the skewness and the flatness. It can be used the raw data of approximate calculation and turbulent modelling.

Surface Hardening of SM45C Steel by CO2 Laser (CO2 레이저를 이용한 SM45C 강의 표면경화)

  • Park, J.S.;Lee, O.Y.;Song, K.H.;Han, Y.H.
    • Journal of the Korean Society for Heat Treatment
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    • v.8 no.1
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    • pp.44-52
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    • 1995
  • The specimen for laser hardening have been carried out using SM45C which is coated with black paint or graphite for better absorption. Segmented mirror was used in order to produce a square beam ($10{\times}10mm$) at the surface with a homegeneous intensity distribution across the beam. $CO_2$-Laser power was changed from 2kW to 4kW and transfer velocity was varied from 0.1m/min to 2.0m/min. The maximum hardness and case depth of SM45C steel are 790Hv and 1.5mm by laser hardening. When the surface of specimens was melted during laser hardening. the surface hardness of SM45C steel was decreased. The surface hardness of 2 layer coated specimen(black paint: $15.4{\mu}m$, graphite coating: $9.5{\mu}m$) was increased than that of 1 layer coated specimen. It is desirable to prepare 2 or more coating layer on the steel surface in order to sufficient case depth and hardness in laser hardening. The graphite coating on the specimen surface was obtained more uniform temperature distribution than black paint coating in laser hardening process.

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Antioxidative and Antimutagenic Characteristics of Melanoidin Related Products (Melanoidin의 항산화성 및 항돌연변이원성)

  • 최홍식;이창용
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.2
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    • pp.246-252
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    • 1993
  • Melanoidins, as brown colored polymers, are formed through the diversified reaction systems of Maillard type and other reactions. Melanoidins are important components in relation to food quality and also are known to have antioxidative, mutagenic and antimutagenic activities. Since these aspects have been extensively reviwed elsewhere, only the recent studies regarding to their antioxidative and antimutagenic activities are discussed in this review. Even though their mechanisms are not clearly identified, melanoidins or specific fractions isolated from their mixtures have shown varied antioxidative activities depending on the reaction systems and reaction conditions. Those activities presumely are derived from the complex functional properties of hydrogen / electron donors and metal chelating power, which are originated from their reductone structure and others. It is considered that pyrolysate and other mutagens are formed by the given conditions in some cases during browning reaction, whereas melanoidins and their fractions have antimutagenic effects on chemical and other mutagens. There are positive correlationship among the color intensity, antioxidative activity and antimutagenicity of melanoidins or their fractions. These suggest that the antimutagenicity of melanoidins could be attributed to their antioxidative properties, however, it might also be due to other factors, because the relevant responses for antimutagenicity are very complicate and not clear. Accordingly, further studies are required to determine the actual acitivities and mechanisms involved in antioxidation and (anti)mutagenicity of melanoidins by reaction systems / conditions and by the isolated fractions. And also, additional studies are needed to evaluate the applications of melanoidins and their relevant effects to food and human health.

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Two-sample Linear Rank Tests for Efficient Edge Detection in Noisy Images (잡음영상에서 효과적인 에지검출을 위한 이표본 선형 순위 검정법)

  • Lim Dong-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.4 s.42
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    • pp.9-15
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    • 2006
  • In this paper we propose Wilcoxon test, Median test and Van der Waerden test such as linear rank tests in two-sample location problem for detecting edges effectively in noisy images. These methods are based on detecting image intensity changes between two pixel neighborhoods using an edge-height model to perform effectively on noisy images. The neighborhood size used here is small and its shape is varied adaptively according to edge orientations. We compare and analysis the performance of these statistical edge detectors on both natural images and synthetic images with and without noise.

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The Optical Filtering Effect of a RSOA-based Broadband Light Source in a Bidirectional WDM-PON System (파장분할 다중화 수동광 네트워크에서 적용된 반사형 반도체 증폭기 기반의 광역선폭 광원의 광필터 특성 의존성)

  • Choi, Bo-Hun
    • Korean Journal of Optics and Photonics
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    • v.22 no.3
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    • pp.122-128
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    • 2011
  • The AWG-filtering effect was investigated on a bidirectional 100-GHz-channel-spacing WDM-PON link using spectrum-sliced and RSOA-amplified light sources for downstream signals and a wavelength reuse technique for upstream signals. Signal performances of three different filtering AWGs, including Gaussian, trapezoidal, and rectangular types, were compared on link transmission with fiber nonlinear effects. As an extinction ratio of a downstream signal varied, the effect for both directional signals was analyzed and optimized. It was found that there was an optimal pass bandwidth of an AWG for the balance between relative intensity noise decrement and cross phase modulation noise increment as the bandwidth got wider.

Microwave Radiation Effects on the Process of Escherichia coli Cultivation

  • Kuznetsov, Denis;Volkhin, Igor;Orlova, Ekaterina;Neschislyaev, Valery;Balandina, Alevtina;Shirokikh, Anna
    • Microbiology and Biotechnology Letters
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    • v.47 no.3
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    • pp.372-380
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    • 2019
  • Modern biotechnological industries have been attempting to improve the efficiency of bacterial strain cultivation. Millimeter wave electromagnetic radiation can have a varied influence on E. coli cultivation processes. The results of the study revealed that when a microwave radiation of low intensity is applied to positively adjust the conditions for the accumulation of bacterial culture biomass, a significant role is played not only by radiation parameters, but also by concomitant biological factors, which influence the reproducibility of the cultivation process and help obtain a useful biotechnological effect. The authors suggest a model that can be used to study the molecular mechanisms underlying the changes in the buildup of E. coli biomass under the influence of electromagnetic radiation.

A Phenomenological Study on the Cravings of Alcoholics (알코올중독자가 경험하는 갈망에 관한 현상학적 연구)

  • Keun Young, Yang;Hyang Sook, Kang
    • The Journal of Korean Society for School & Community Health Education
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    • v.23 no.4
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    • pp.63-79
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    • 2022
  • Objectives: The purpose of this study is to reveal the phenomenological meaning and experience of alcohol craving experienced by alcoholics through qualitative research. Methods: From November 8, 2020 to October 10, 2022, in-depth interviews were conducted with four recovering alcoholics within two years of a single week who were diagnosed with alcoholism in the past and had been hospitalized for alcoholism problems. The data were analyzed using phenomenological qualitative research methods. Results: The alcohol craving experienced by alcoholics worked in connection with the life of alcoholics. Alcohol intensity was not entirely determined by external factors, but varied by the individual's internal state and circumstances surrounding the individual, and cravings were found to be classified into when control and intervention were possible. Also, the power to neutralize alcohol cravings was a warm 'self-compassion' mind. Conclusion: This study presented a new perspective on alcohol craving, and based on this perspective, the necessity of developing an alcohol addiction prevention program and a recurrence prevention program was presented. In addition, the basis for emphasizing the necessity of complete abstinence in health education services for preventing alcohol and preventing recurrence in the community was presented.