• Title/Summary/Keyword: Light controls

Search Result 244, Processing Time 0.036 seconds

An Experimental Study of the Optimum Spatial Characteristics and Location of Photosensor for Daylight Responsive Dimming Systems (광센서 조광제어시스템의 광센서 최적 방향성과 위치에 관한 실험적 연구)

  • 정봉근;최안섭
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.17 no.5
    • /
    • pp.8-14
    • /
    • 2003
  • The daylight responsive dimming system, which uses daylight and automatically controls the light output of electric lighting according to the amount of 3.vailable daylight, is an energy saving system Successful performance relies on how photosensor signal can precisely represent workplace illuminance. However, it is not accurately identified due to the dynamic nature of the sun and the sky changed with respect to different seasons or time. The purpose of this research is to identify the correlation between workplace illuminance and photosensor signals, and propose an optimal location and spatial characteristics of the photosensor through experiments, which minimizes the above impacts and improve system performance.

The Methylenetetrahydrofolate Reductase C677T Polymorphism and Breast Cancer Risk in Asian Populations

  • Rai, Vandana
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.14
    • /
    • pp.5853-5860
    • /
    • 2014
  • Background: Methylenetetrahydrofolate (MTHFR) is the key enzyme of the folate metabolic pathway and several studies have pointed to association between the MTHFR C677T polymorphism and breast cancer risk. Although significant association was observed in some studies, in others no clear link could be established. Objective: A meta-analysis of published Asian case control studies was therefor carried out to shed further light on any C677T breast cancer association. Materials and Methods: PubMed, Springer Link, Google Scholar and Elsevier databases were searched for case control studies of associations between MTHFR C677T polymorphism and breast cancer risk. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association. A total of 36 studies including 8,040 cases and 10,008 controls were included in the present meta-analysis. Results: Overall, a significantly elevated breast cancer risk was associated with the T allele and TT genotype in homozygote comparison and dominant genetic models when all studies were pooled into the meta-analysis (T vs C (allele contrast model): OR=1,23, 95%CI=1.13-1.37, p=0.000 ; TT vs CC(homozygote model): OR=1.38, 95%CI=1.16-1.63, p=0.0003; TT+CT vs CC (dominant model): OR=1.12, 95%CI=1.01-1.23, p=0.02). Conclusions: The present meta-analysis strongly suggested a significant association between the MTHFR C677T polymorphism and risk of breast cancer in Asian populations.

Performance Evaluation of Node.js for Web Service Gateway in IoT Remote Monitoring Applications

  • Nkenyereye, Lionel;Jang, Jong-Wook
    • International Journal of Advanced Culture Technology
    • /
    • v.4 no.3
    • /
    • pp.13-19
    • /
    • 2016
  • The growth of mobile devices in Internet of Things (IoT) leads to a number of remote and controlling system related IoT applications. For instance, home automation controlling system uses client system such web apps on smartphone or web service to access the home server by sending control commands. The home server receives the command, then controls for instance the light system. The web service gateway responsible for handling clients' requests attests an internet latency when an increasing number of end users requests submit toward it. Therefore, this web service gateway fails to detect several commands, slows down predefined actions which should be performed without human intervention. In this paper, we investigate the performance of a web server-side platgorm based event-driven, non-blocking approach called Node.js against traditional thread-based server side approach to handle a large number of client requests simultaneously for remote and controlling system in IoT remote monitoring applications. The Node.JS is 40% faster than the traditional web server side features thread-based approach. The use of Node.js server-side handles a large number of clients' requests, then therefore, reduces delay in performing predefined actions automatically in IoT environment.

Polscope-Assisted Enucleation for Nuclear Transfer in Mice

  • Won Ji Young;Kang Jee Hyun;Shim Hosup
    • Reproductive and Developmental Biology
    • /
    • v.28 no.4
    • /
    • pp.257-260
    • /
    • 2004
  • Efficiency of somatic cell nuclear transfer was investigated in mice. First, oocyte activation was induced by SrCl₂, and the rate of development was compared with embryos from normal fertilization. Although more than one half of SrCl₂-treated oocytes developed to blastocysts (146/262, 55.7%), the rate of blastocyst formation was significantly lower than normal fertilization controls (59/79, 74.6%). Second, enucleation of oocytes was performed using Polscope that enables non-invasive visualization of metaphase spindles. Such approach could not only avoid damage of oocytes during an exposure to UV light often employed in conventional enucleation procedures, but could also assure the removal of nuclei from all oocytes operated because of monitoring the location of spindles during an entire process of enucleation. Morphologically normal blastocysts were obtained from the transfer of cumulus cell nuclei into enucleated oocytes. However, the rate of development into the blastocyst stage was still low (4/93, 4.3%). This reflects that the nuclear transfer procedure used in this study was not sufficiently optimized, and other factors may also impact greatly the efficiency of nuclear transfer. Including an induction of oocyte activation and method of enucleation tested in this study, a lot more elements are remained to be optimized to improve the efficiency of somatic cell nuclear transfer in mice.

Weathering of coal and kerogen : implications on the geochmical carbon and oxygen cycle and the environmental geochemical reactions (탄질 유기물과 케로젠의 풍화 : 탄소와 산소의 지화학적 순환 및 환경화학적 반응에 미치는 영향)

  • 장수범
    • Economic and Environmental Geology
    • /
    • v.32 no.1
    • /
    • pp.101-111
    • /
    • 1999
  • Sedimentary organic matter, exposed to continental surficial environment, reacts with oxygen supplied from the atmosphee and forms carbon-containing oxidation products. Knowledge of the rate and mechanisms of sedimentary organic matter weathering is important because it is one of the major controls on atmospheric oxygen level through geologic time. Under the abiological conditions, the oxidation rate of coal organic matter by molecular oxygen is enhanced by the increase of oxygen concentration and temperature. At ambient temperature and pressure, aqueous coal oxidation results in the formation of dissolved $CO_2$ dissolved organic carbon and solid oxidation products which are all quantitatively significant reaction products. The effects of pH, ultraviolet light, and microbial activity on the weathering of sedimentary organic matter are poorly contrained. Based on the results of geochmical and environmental studies, it is believed that the photochemical reaction should play an important role in the decomposition and oxidation of sedimentary organic matter removed from the weathering profile. At higher pH conditions, the production rate of DOC can be accelerated due to base catalysis. These high molecular weight oranic matter can react with man-made pollutants such as heavy metal ions via adsorption/desorption or ion exchange reactions. The effect of microbial activity on the oxidative weathering of sedimentary organic matter is poorly understood and remains to be studied.

  • PDF

Transgelin is Required for Agonist-induced $Ca^{2+}$-Sensitization in Vascular Contractility: Evidence from an Antisense Approach (칼슘이온 감작이 포함된 Transgelin의 혈관 평활근 수축성 조절)

  • Je, Hyun-Gon;Je, Hyun-Dong
    • YAKHAK HOEJI
    • /
    • v.53 no.3
    • /
    • pp.156-160
    • /
    • 2009
  • The present study was undertaken to determine whether transgelin participates in the regulation of vascular smooth muscle contraction and, if so, to investigate the mechanism. By PCR homology cloning, the cDNA sequence of ferret transgelin was determined and phosphorothioate antisense and random oligonucleotides were synthesized and introduced into strips of ferret aorta by a chemical loading procedure. Treatment of ferret aorta with transgelin antisense oligonucleotides resulted in a significant decrease in protein levels of transgelin to sham- or random sequence-loaded muscles, but no change in the protein levels of actin. Contraction in response to a phorbol ester was significantly decreased in antisense-treated muscles compared to sham- or random sequence-loaded controls. Neither basal intrinsic tone nor the contraction in response to phenylephrine was significantly affected by the antisense treatment. The data indicate that transgelin plays a significant role in the regulation of contraction and suggest that in a tonically active smooth muscle transgelin may function as a signalling protein to facilitate PKC or ERK-dependent signalling rather than thick filament regulation including $Ca^{2+}$ or calmodulin dependent regulation of myosin light chain kinase.

Resistance Spot Welding Characteristics of Mg Alloy Applying Current Waveform Control (전류 파형 제어를 적용한 마그네슘 합금의 저항 점 용접 특성)

  • Choi, Dong-Soon;Hwang, In-Sung;Kim, Dong-Cheol;Ryu, Jae-Wook;Kang, Moon-Jin
    • Journal of Welding and Joining
    • /
    • v.32 no.2
    • /
    • pp.70-75
    • /
    • 2014
  • In automotive industry, applying of Mg alloy to autobody has been issued recently as a light metal. But poor resistance spot weldability of Mg alloy is blocking commercialization. So studies on improving resistance spot weldability of Mg alloy is increasing continuously. For reduce loss of heat input during welding, inverter DC power source is considered because of short rise time to target welding current. But rapid rising of welding current can increase temperature rapidly in nugget and oxide film between electrode and base metal, and that causes generating expulsion on low welding current range. In this study, for increase optimum welding current range and prevent generating expulsion, applicate various types of welding current waveform controls during resistance spot welding. For analysis effects of each current waveform control, acceptable welding current regions according to electrode force and welding time is determined and lobe diagram is derived. In result, pre heat is proposed as optimum type of welding current waveform control.

Algin-Impregnated Vascular Graft II. Preliminary Animal Study

  • Jin Ho Lee;Byu
    • Journal of Biomedical Engineering Research
    • /
    • v.12 no.3
    • /
    • pp.157-164
    • /
    • 1991
  • Microvel $^{\textregistered}$ double velour graft impregnated with a biodegradable algin was studied as a new vatscular graft. It is impervious to blood but still retains high porosity. This graft does not require preclotting during implantation and has good tissue ingrowth and biological healing properties. Two vascular grafts impregnated with algin (6mm in diameter) were implanted in the aorta of mongrel dogs without preclotting. Two identical grafts were preclctted and served as controls. The grafts were harvested 2 and 4 months postoperatively, and the healing pattern was examined by a light microscope after hemRtoxylineosin staining. It was observed that endothelial cells were incompletely covered on both algin-impregnated and control grafts after 2 month Implantation, while they were fully covered on both grafts after 4 month. There were no significant differences in subendothelial granulation tissue organization and fibrinoid material absorption between the algin-impregnated and control grafts. The algin-impregnated graft did not show any harmful effect on the healing and thus can be a new promising graft which is not necessary preclotting during the implantation.

  • PDF

Analyses on Photosensor Illuminance for Prediction of Fluctuating Illuminance by Daylight Dimming Control Systems (조광제어 시스템 적용시 실내조도의 변동예측을 위한 포토센서의 주광조도 분석)

  • Kim, Soo-Young
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.22 no.11
    • /
    • pp.788-797
    • /
    • 2010
  • This study examines the influence of fluctuating daylight illuminance on daylight dimming control systems. Field measurements were performed for a full-scale mocked-up model under various daylight conditions in winter. Fluctuating ranges for a partially-shielded photosensor were great when the variation of sky ratio was great. When solar altitude was lower the illuminance and fluctuating range of illuminance were great due to the influence of direct components of daylight and the interrefelction between surfaces in rear area of space. It implies that daylight dimming system would not function effectively, unless the desktop illuminance by daylight is enough. Fluctuation ranges of photosensor illuminance were lower than 50 lx under clear sky conditions, but they were greater than 100 lx under partly-cloudy sky conditions. It means that the fluctuation range of electric light output of lighting fixture would greater under the partly-cloudy conditions and cause potential visual annoyance to occupants. Outdoor vertical illuminance reaching the windows would be an effective factor that can be used to predict the fluctuation of photosensor signals for effective controls of daylight dimming system.

An Experimental Study on the Effects of Triamcinolone Acetonide on the Wound Healing of Rat Tongue (Triamcinolone acetonide가 설 창상치유에 미치는 영향에 관한 실험적 연구)

  • 김능세;이승우
    • Journal of Oral Medicine and Pain
    • /
    • v.7 no.1
    • /
    • pp.5-26
    • /
    • 1982
  • In order to study the effects of traimcinolone acetonide on the wound healing of tongue, eight two healthy albino rats were asesthetized with pentothal. The wound, approximately 1mm in depth and 2mm in diameter, was created on the midlateral aspect of tongue with the tip of small rongeur fourcep. Forty one animals were employed in one of the following groups:(I) Control group: Received 0.5ml/100gm B.W. of saline suspension intralesionally at weekly interval until sacrificed.(II) Experimental group: Received $100\mu\textrm{g}/100gm$ B.W. of trimacinolone acet- onide suspension intralesionally at weekly interval until sacrificed. Biopsy specimens of wounds were taken at 6,18,24 hours, 2,3,5,7,14 and 28 days after wounding. The specimens were sectioned, and observed with light microscope and electron microscope. The results were as follows : 1. In the triamcinolone acetonide treated wound, the epithelial and fibroblastic regeneration were dealayed when compared with controls. 2. After triamcinolone acetonide treated, edema was decreased at the early stage of wound healing. 3. In the triamcinolone acetonide treated wound, the fibroblasts exhibited fine morphological changes and reduction of collagen formation. It seems that triamcinolone acetonide inhibits fibroblast function.

  • PDF