• 제목/요약/키워드: Spread pattern

검색결과 323건 처리시간 0.025초

A study on the burned pattern of plastic wastebasket by reconstruction (플라스틱 휴지통의 연소 재현 실험을 통한 발화지점 축소 방법)

  • An, Seong-Il
    • Journal of Korean Institute of Fire Investigation
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    • 제3권1호
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    • pp.38-42
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    • 2003
  • There are many origins of fire which are offered by many path, such as cigarette-butt, light of match, playing with fire, arson, and other, in and around wastebasket. Because of above-mentioned thing and the quality of the plastic, it is very difficult to discriminate the difference of burned pattern between in and around wastebasket, between an accidental fire and arson in oder to investigate the point of fire. In this study, the wastebaskets filled up with 2/3 combustibles, and then, in and around wastebasket using the gas lighter by ignitor, and we observe how the fire spread. As a result, if wastebaskets are burned inside the limit 50%, we discriminate the difference of burned pattern between in and around wastebasket. But, if wastebaskets are burned more thant 50%, it is impossible to discriminate the difference of burned pattern between in and around wastebasket.

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Beam Diversity Receiver Using 7-Element ESPAR Antenna (전자 빔 조향 기생 배열 안테나를 사용한 빔 다이버시티 수신기)

  • An, Changyoung;Lee, Seung Hwan;Ryu, Heung-Gyoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제39A권1호
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    • pp.36-42
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    • 2014
  • In this paper, we propose receiver using ESPAR antenna for diversity gain. The proposed receiver receive signal by changing direction of beam pattern alternately in the OFDM symbol time period when DoA is estimated. In this way, the proposed receiver obtains diversity gain. The proposed receiver has single RF chain. If beam direction is changed alternately then it causes spectrum spread. And then, ICI occur because of spectrum spread. This interference can be equalized at the frequency domain equalizer such as ZF, MMSE and ML. In simulation, the proposed system receive signal using beam pattern of $60^{\circ}$ and beam pattern of $120^{\circ}$ alternately in OFDM symbol time period when it is assumed that DoA is $60^{\circ}$ and $120^{\circ}$. The performance results confirm that it is possible that the proposed receiver obtains diversity gain.

Analyzing Spread Rate of Samcheok Forest Fire Broken out in 2000 Using GIS (GIS 응용(應用)에 의한 2000년(年) 삼척(三陟) 산불의 확산속도(擴散速度) 분석(分析))

  • Lee, Byung-Doo;Chung, Joo-Sang;Kim, Hyung-Ho;Lee, Si-Young
    • Journal of Korean Society of Forest Science
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    • 제90권6호
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    • pp.781-787
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    • 2001
  • The spread rate of forest fire was analyzed on Samcheok forest fire that broke out on April 7, 2000 in Kunduck-Myun, Samcheok-City, Kangwon-Province and lasted for about 9 days. The spatial database including topography, overstory species distribution, micro-climate, daily fire front lines for the area was built using GIS and the daily spread pattern was investigated to determine a multiple regression equation to estimate forest fire spread rate. The results of the investigation showed that, on the first day, the forest fire spreaded out extremely fast up to 12.3m/min at about 10 a.m. until noon. After that, the forest fire spread rate fluctuated and slowed down as low as below 1m/min and quenched on April 15. The daily area-based spread rate along the fire spread line got to the peak of about 5,700ha on April 11, of which spread rates were recorded as 2.84m/min in the first half and 1.10m/min in the second half. Also, it was found that slope aspect, wind velocity and % area distribution of Pinus densiflora are the major factors affecting the spread rate of forest fire in this area.

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Effect of the Pressure and the Flow Pattern in a Sac Chamber of a Diesel Injection Nozzle on the Issued Spray Behaviors (디젤 연료분사노즐 색크실내의 압력과 유동패턴이 분류의 분열거동에 미치는 영향)

  • 김장헌;송규근
    • Transactions of the Korean Society of Automotive Engineers
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    • 제8권1호
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    • pp.48-53
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    • 2000
  • The effects of the internal flow in a diesel injection nozzle on the atomization of the spray has been investigated experimentally. Flow visualization was made using a transparent acrylic model nozzle. And also, measurement of the sac chamber pressure was made for clartfying the effect of pressure fluctuation in the sac chamber on the wpray behaviors. The geometry of the model nozzle was scaled up 10 times of the actual nozzle and the injection pressure for the model nozzle was adjusted so as to achieve a Reynolds number at the discharge hole which was the same as the actual nozzle. Polystyrene tracers, a laser sheet light and a still/high speed video camera were used to visualize the flow pattern in the sac chamber. When the needle lift was small, the high turbulence in the sac chamber generated by the high velocity seat flow made the spread angle of the spray large. Cavitation which arose in the sky chamber induced the pressure fluctuation and then affects the spread angle of the spray.

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Spread Patterns of Thermal Effluent Discharged From Young-Kwang Nuclear Power Plant Using Remote Sensing Data

  • Han J. G.;Yeon Y. K.;Chi K. H.
    • Proceedings of the KSRS Conference
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.331-335
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    • 2004
  • This study is focused to analyze the movement of thermal effluent dischargeed from nuclear power plant by season, ebb and flow, and before and after foundation of tide embankment using thermal infrared band image of 28 scenes observed from Landsat from 1987 to 2004, which is the early stage of operation of young-kwang nuclear power plant. In diffusion of thermal effluent discharge by seasons, spring and summer is spreading further than autumn and winter. It is considered to distribute widely mixed with thermal effluent discharge and hot water, which is distributed naturally along the seaside. It is known the fact that tidal currents control the direction of diffusion of thermal effluent discharge by the change of ebb and flow. Namely, it is distributed widely on the Southwest direction along the seaside by tidal currents when ebb and, it is moved widely on the Northeast direction along the seaside by tidal current when flood. However, in the early stage of flood current, the mainstream of thermal effluent discharge is spread on Southwest direction and, the direction is changed on North­east way when the latter period of flood current. Similarly, in the early stage of ebb current, the mainstream of thermal effluent discharge is spread on Northeast direction and, the direction is changed on Southwest direction when the latter period of ebb current. As the result of comparing to the diffusion pattern of thermal effluent discharge before and after the foundation of seawall, discharged thermal effluent from the drain of plant by the foundation of dike is shown as curved circle pattern on Northeast to West direction from the ending portion of the seawall.

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Molecular Surveillance of Pfkelch13 and Pfmdr1 Mutations in Plasmodium falciparum Isolates from Southern Thailand

  • Khammanee, Thunchanok;Sawangjaroen, Nongyao;Buncherd, Hansuk;Tun, Aung Win;Thanapongpichat, Supinya
    • Parasites, Hosts and Diseases
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    • 제57권4호
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    • pp.369-377
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    • 2019
  • Artemisinin-based combination therapy (ACT) resistance is widespread throughout the Greater Mekong Subregion. This raises concern over the antimalarial treatment in Thailand since it shares borders with Cambodia, Laos, and Myanmar where high ACT failure rates were reported. It is crucial to have information about the spread of ACT resistance for efficient planning and treatment. This study was to identify the molecular markers for antimalarial drug resistance: Pfkelch13 and Pfmdr1 mutations from 5 provinces of southern Thailand, from 2012 to 2017, of which 2 provinces on the Thai- Myanmar border (Chumphon and Ranong), one on Thai-Malaysia border (Yala) and 2 from non-border provinces (Phang Nga and Surat Thani). The results showed that C580Y mutation of Pfkelch13 was found mainly in the province on the Thai-Myanmar border. No mutations in the PfKelch13 gene were found in Surat Thani and Yala. The Pfmdr1 gene isolated from the Thai-Malaysia border was a different pattern from those found in other areas (100% N86Y) whereas wild type strain was present in Phang Nga. Our study indicated that the molecular markers of artemisinin resistance were spread in the provinces bordering along the Thai-Myanmar, and the pattern of Pfmdr1 mutations from the areas along the international border of Thailand differed from those of the non-border provinces. The information of the molecular markers from this study highlighted the recent spread of artemisinin resistant parasites from the endemic area, and the data will be useful for optimizing antimalarial treatment based on regional differences.

Arrangement Methods of Pattern and Weaving Types of Fabrics During 16~17th Century - Centering Flower Patterned Fabrics of Exhumed Clothing in Chosun Dynasty - (16~17세기 직물유형과 문양의 배치구도에 관한 연구 - 조선시대 출토복식에 나타난 화문직을 중심으로 -)

  • Park, Mun-Young;Kim, Ho-Jung;Park, Ok-Lyun
    • Fashion & Textile Research Journal
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    • 제8권4호
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    • pp.400-406
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    • 2006
  • The purpose of this study is to investigate characteristics of arrangement methods and weaving types of fabrics during 16-17 century. Research was done through the references of exhumed clothing in Chosun Dynesty. Seeing the waving types of fabrics of flower patterned fabrics of total 108 items, satin damask(Dahn) was 71items, took the majority. And the next order was twill(Neung) and plain(Ju). It means Dahn was the most popular fabric among the upper classes. It was regarded as one of the noble textiles, because of its luxurious appearance and pleasant touch. Flower patterned plain fabric(Munju) was found only 9items, even though the plain fabric was the most common used type. Assumed for the reason, Chosun government had restrict to extravagance of the people. In terms of the arrangement of flower pattern, it can be classified into three methods. The most common arrangement method was Arabesque type, followed by open order shaped type and scattering shaped type. In the repetition of pattern, there were brick-shaped pattern and half drop pattern which were spread flower pattern all over the surface of fabric.

Analysis of the Disease Spread in a Livestock Building Using Tracer Gas Experiment (추적가스 실험을 통한 축사 내 질병 확산 분석)

  • Song, Sang-Hyeon;Lee, In-Bok;Kwon, Kyeong-Seok;Ha, Tae-Hwan;Bitog, Jessie P.;Hong, Se-Woon;Seo, Il-Hwan;Moon, Oun-Kyeong;Kim, Yeon-Joo;Choi, Eun-Jin
    • Journal of The Korean Society of Agricultural Engineers
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    • 제54권3호
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    • pp.37-45
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    • 2012
  • Recently, the livestock industry in Korea was heavily affected by the outbreak of official livestock diseases such as foot and mouse disease, high pathogenic avian influenza, swine influenza, and so on. It has been established that these diseases are being spread through direct contact, droplet and airborne transmission. Among these transmissions, airborne transmission is very complex in conducting field investigation due to the invisibility of the pathogens and unstable weather conditions. In this study, the airborne transmission was thoroughly investigated inside a pig house by conducting tracer gas ($CO_2$) experiment because experiment with real pathogen is limited and dangerous. This is possible as it can be assumed that the flow is similar pattern very fine particles and gas. In the experiment, the ventilation structure as well as the location of gas emission were varied. The $CO_2$ detection sensors were installed at 0.5 and 1.3 m height from the floor surface. The tracer gas level was measured every second. Results revealed that the direction of spread can be determined by the response time. Response time refers to the time to reach 150 ppm from the gas emission source at each measuring points. The location of the main flow as well as the gas emission was also found to be very important factor causing the spread.

Robust pattern watermarking using wavelet transform and multi-weights (웨이브렛 변환과 다중 가중치를 이용한 강인한 패턴 워터마킹)

  • 김현환;김용민;김두영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제25권3B호
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    • pp.557-564
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    • 2000
  • This paper presents a watermarking algorithm for embedding visually recognizable pattern (Mark, Logo, Symbol, stamping or signature) into the image. first, the color image(RGB model)is transformed in YCbCr model and then the Y component is transformed into 3-level wavelet transform. Next, the values are assembled with pattern watermark. PN(pseudo noise) code at spread spectrum communication method and mutilevel watermark weights. This values are inserted into discrete wavelet domain. In our scheme, new calculating method is designed to calculate wavelet transform with integer value in considering the quantization error. and we used the color conversion with fixed-point arithmetic to be easy to make the hardware hereafter. Also, we made the new solution using mutilevel threshold to robust to common signal distortions and malicious attack, and to enhance quality of image in considering the human visual system. the experimental results showed that the proposed watermarking algorithm was superior to other similar water marking algorithm. We showed what it was robust to common signal processing and geometric transform such as brightness. contrast, filtering. scaling. JPEG lossy compression and geometric deformation.

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The Effects of Restrictions in Economic Activity on the Spread of COVID-19 in the Philippines: Insights from Apple and Google Mobility Indicators

  • CAMBA, Abraham C. Jr.;CAMBA, Aileen L.
    • The Journal of Asian Finance, Economics and Business
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    • 제7권12호
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    • pp.115-121
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    • 2020
  • This study aims to investigate the effects of restrictions in economic activity on the spread of COVID-19 in the Philippines. This research employs daily time-series data of confirmed new COVID-19 cases, Apple mobility trends (i.e., use of public transport to destinations, volume of people driving, and amount of walking to destinations) and Google community mobility (i.e., visits to transit stations, visits to workplaces, and staying-at-home) indicators covering the period February 17 to September 11, 2020. The analysis starts by establishing the correlation pattern of new confirmed COVID-19 daily infections to each independent variable. The results show negative linear correlation of the number of new COVID-19 daily infections with less visit to transit station, increase stay-at-home, less use of public transport, and less amount of walking to destinations. Interestingly, the number of new COVID-19 daily infections indicates some form of positive linear correlation with visits to workplaces and volume of people driving. Moreover, employing robust least square regression via the method of MM-estimation, major findings reveal that across mobility measures, staying-at-home has the highest impact on reducing the spread of COVID-19, followed by visiting transit stations less, less use of public transport, less amount of walking, and less workplace visits.