• Title/Summary/Keyword: scale-model

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A Study on the Hybrid Policing of Policing Space Follow Character Alteration of Space (공간의 성격변화에 따른 Hybrid Policing의 치안활동 영역에 관한 이론적 고찰)

  • Seo, Jin-Seok
    • Korean Security Journal
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    • no.11
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    • pp.87-104
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    • 2006
  • When the character of space could be dichotomized into the existing public space and private space, social order could be maintained by public policing only, Since enormous private property was formed and private space was enlarged by the development of capitalism, however, the necessity of private policing system came to the front. The large capitalists began to establish separate policing system to protect their property and safety. However, as social alteration was further diversified scale of economy was enlarged, the character of space could not be simply explained owing to the formation of space that could not be explained by simple dichotomous division. Namely, the 3rd space was formed as middle class between public space and private space. The 3rd space created additional demand of policing besides the existing public policing and private policing. The policing system to safety such demand of policing is called hybrid policing. As policing system in which character and legal status of public policing and private policing are mixed, the hybrid policing system may be originated from the diversification of demand of policing. Johnston insists that the demand of hybrid policing system will be further increased, becoming the model of policing system in the future. In Korea, the police guard system or special guard system can be classified into the type of hybrid policing. In accordance with the trend of diversified demand of policing in the future, I suggest to develop Korean model of hybrid policing system so that it can be utilized in elevating the policing index in Korean society.

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Behavior of Yellow Tail , Seriola quinqueradiata and File Fish , Navodon Modestus to the Model Set Net (모형정치망에 대한 방어 및 말쥐치의 행동)

  • Gwon, Hyeok-Sa;Lee, Byeong-Gi
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.26 no.3
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    • pp.230-236
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    • 1990
  • To examine the behavior of yellow tail Seriola quinqueradiata and of file fish Navodon modestus to set net, the 1/30 scale model net of the actual set net used in the east coast of Korea was made of netting and set in the indoor experimental tank(700cm W$\times$700cm L$\times$100cm D), of which the water depth was kept 70cm. Total length of yellow tail examined were 37~45cm and file fish were 18~21cm. The fishes were released as groups of 3 to 20 individuals. The number of fish entered into the pound net or the bag net, escaped from the net was counted every minute and accumulated for 10minutes to check the ratio entered and the ratio escaped. The result obtained can be summarized as follows: 1. In case of yellow tail, even though the ratio entered into the pound net was not so high, that into the bag net was comparatively high. Traces of the fish swimming were comparatively smooth and both entering into the pound net and escaping from it was easily done. 2. In case of file fish, even though the ratio entered into the pound net was higher than that of yellow tail, that into the bag net was lower than that into the pound net. Traces of the fish swimming were roundly meandered. Entering into the bag net was not so smoothly done, even though that into the playground was smoothly done. 3. Both yellow tail and file fish, the ratio escaped from the bag net was almost0 and that from the pound net was less than 10%.

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Designation of fuel oil scrubber nozzle positioning using CFD analysis and PIV methods (CFD 해석 및 PIV 실험을 통한 연료유 스크러버의 노즐 위치선정)

  • Kim, In-Cheol;Kim, Chang-Goo;Park, Sung-Jin;Cho, Dong-Yeon;Lee, Young-Ho
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.7
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    • pp.773-778
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    • 2015
  • Global warming has recently become an issue that has resulted in a growing trend to minimize environmental pollution. The International Maritime Organization (IMO) has shown that the majority of marine atmospheric pollution occurs as a result of emissions from marine vessels. Therefore, the environmental regulations and emission standards regarding marine vessels have gradually become stricter, and the research and development in this area is experiencing significant progress. In this study, a nozzle for a fuel oil scrubber was investigated using computational fluid dynamics (CFD) and particle imaging velocimetry (PIV). Experiments were conducted on scaled-down model of the scrubber to determine its performance, which was then compared with CFD results. Based on the experimental results, it was found that at a spray angle of $66^{\circ}$, the spray velocity at the nozzle was 20.1 m/s. From this comparison, a full-scale scrubber model was analyzed using CFD, and the effect of the positioning of the nozzle was studied.

An experimental study on the ground movement around a square pipe by its penetration for trenchless construction in sandy ground (사각형 강관을 이용한 비개착 시공에 따른 지반거동의 분석: 모래지반에 대한 모형 토조실험)

  • Choi, Soon-Wook;Park, Young-Taek;Chang, Soo-Ho;Bae, Gyu-Jin;Lee, Ki Taek;Baek, Yong Ki
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.5
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    • pp.485-501
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    • 2012
  • This study aims to experimentally investigate ground settlement and ground movement around the square pipe by its penetration in sandy ground. A series of laboratory model tests were carried out with a small-scale auger equipment for penetration of a square pipe as well as a newly designed test box with a sand raining equipment. From the experiments, it is shown that a square pipe induces ground movement evenly around it in a low overburden condition. However, as the overburden becomes higher, ground movement by a square pipe is concentrated mainly above it. Especially, horizontal strain above the square pipe was mainly dominated by its penetration. In addition, sand surface movement is the smallest in case of the dimensionless penetration rate equal to 0.2. When its penetration rate of the square pipe is fixed, the rotation speed of auger controls surface movement whether it is settlement or heaving. Therefore, the selection of an optimal dimensionless rate for the square pipe is a key design factor to minimize ground settlement in a trenchless construction.

Cervical Cancer Screening and Analysis of Potential Risk Factors in 43,567 Women in Zhongshan, China

  • Wang, Ying;Yu, Yan-Hong;Shen, Keng;Xiao, Lin;Luan, Feng;Mi, Xian-Jun;Zhang, Xiao-Min;Fu, Li-Hua;Chen, Ang;Huang, Xiang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.2
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    • pp.671-676
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    • 2014
  • Objective: The objective of this study was to establish a program model for use in wide-spread cervical cancer screening. :Methods: Cervical cancer screening was conducted in Zhongshan city in Guangdong province, China through a coordinated network of multiple institutes and hospitals. A total of 43,567 women, 35 to 59 years of age, were screened during regular gynecological examinations using the liquid-based ThinPrep cytology test (TCT). Patients who tested positive were recalled for further treatment. Results: The TCT-positive rate was 3.17%, and 63.4% of these patients returned for follow-up. Pathology results were positive for 30.5% of the recalled women. Women who were younger than 50 years of age, urban dwelling, low-income, had a history of cervical disease, began having sex before 20 years of age, or had sex during menstruation, were at elevated risk for a positive TCT test. The recall rate was lower in women older than 50 years of age, urban dwelling, poorly educated, and who began having sex early. Ahigher recall rate was found in women 35 years of age and younger, urban dwelling, women who first had sex after 24 years of age, and women who had sex during menstruation. The positive pathology rate was higher in urban women 50 years of age and younger and women who tested positive for human papillomavirus. Conclusion: An effective model for large-scale cervical cancer screening was successfully established. These results suggest that improvements are needed in basic education regarding cervical cancer screening for young and poorly educated women. Improved outreach for follow-up is also necessary to effectively control cervical cancer.

Modeling of the Failure Rates and Estimation of the Economical Replacement Time of Water Mains Based on an Individual Pipe Identification Method (개별관로 정의 방법을 이용한 상수관로 파손율 모형화 및 경제적 교체시기의 산정)

  • Park, Su-Wan;Lee, Hyeong-Seok;Bae, Cheol-Ho;Kim, Kyu-Lee
    • Journal of Korea Water Resources Association
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    • v.42 no.7
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    • pp.525-535
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    • 2009
  • In this paper a heuristic method for identifying individual pipes in water pipe networks to determine specific sections of the pipes that need to be replaced due to deterioration. An appropriate minimum pipe length is determined by selecting the pipe length that has the greatest variance of the average cumulative break number slopes among the various pipe lengths used. As a result, the minimum pipe length for the case study water network is determined as 4 m and a total of 39 individual pipe IDs are obtained. The economically optimal replacement times of the individual pipe IDs are estimated by using the threshold break rate of an individual pipe ID and the pipe break trends models for which the General Pipe Break Prediction Model(Park and Loganathan, 2002) that can incorporate the linear, exponential, and in-between of the linear and exponetial failure trends and the ROCOFs based on the modified time scale(Park et al., 2007) are used. The maximum log-likelihoods of the log-linear ROCOF and Weibull ROCOF estimated for the break data of a pipe are compared and the ROCOF that has a greater likelihood is selected for the pipe of interest. The effects of the social costs of a pipe break on the optimal replacement time are also discussed.

Evaluation of satellite-based soil moisture retrieval over the korean peninsula : using AMSR2 LPRM algorithm and ground measurement data (위성기반 토양수분 자료의 한반도 지역 적용성 평가: AMSR2 LPRM 알고리즘과 지점관측 자료를 이용하여)

  • Kim, Seongkyun;Kim, Hyunglok;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.49 no.5
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    • pp.423-429
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    • 2016
  • This study aims at assessing the quality of the Advanced Microwave Scanning Radiometer 2 (AMSR2) soil moisture products onboard GCOM-W1 satellite based on Land Parameter Retrieval Model (LPRM) soil moisture retrieval algorithm with field measurements in South Korea from March to September, 2014. Results of mean bias and root mean square error between AMSR2 LPRM soil moisture products (X-band) and ground measurements showed reasonable value of 0.03 and 0.16. Also, the maximum of the Pearson correlation coefficients was 0.67, which showed good agreement in terms of temporal variability with ground measurements. By comparing AMSR2 soil moisture with in-situ measurement according to the overpass time and band frequency, X-band products on the ascending time outperformed than those of C1-band and C2-band. Furthermore, this study offers an insight into the applicability of the AMSR2 soil moisture products for monitoring various natural disasters at a large scale such as drought and flood.

A Study on the Effect of Ground-based GPS Data Assimilation into Very-short-range Prediction Model (초단기 예측모델에서 지상 GPS 자료동화의 영향 연구)

  • Kim, Eun-Hee;Ahn, Kwang-Deuk;Lee, Hee-Choon;Ha, Jong-Chul;Lim, Eunha
    • Atmosphere
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    • v.25 no.4
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    • pp.623-637
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    • 2015
  • The accurate analysis of water vapor in initial of numerical weather prediction (NWP) model is required as one of the necessary conditions for the improvement of heavy rainfall prediction and reduction of spin-up time on a very-short-range forecast. To study this effect, the impact of a ground-based Global Positioning System (GPS)-Precipitable Water Vapor (PWV) on very-short-range forecast are examined. Data assimilation experiments of GPS-PWV data from 19 sites over the Korean Peninsula were conducted with Advanced Storm-scale Analysis and Prediction System (ASAPS) based on the Korea Meteorological Administration's Korea Local Analysis and Prediction System (KLAPS) included "Hot Start" as very-short-range forecast system. The GPS total water vapor was used as constraint for integrated water vapor in a variational humidity analysis in KLAPS. Two simulations of heavy rainfall events show that the precipitation forecast have improved in terms of ETS score compared to the simulation without GPS-PWV data. In the first case, the ETS for 0.5 mm of rainfall accumulated during 3 hrs over the Seoul-Gyeonggi area shows an improvement of 0.059 for initial forecast time. In other cases, the ETS improved 0.082 for late forecast time. According to a qualitative analysis, the assimilation of GPS-PWV improved on the intensity of precipitation in the strong rain band, and reduced overestimated small amounts of precipitation on the out of rain band. In the case of heavy rainfall during the rainy season in Gyeonggi province, 8 mm accompanied by the typhoon in the case was shown to increase to 15 mm of precipitation in the southern metropolitan area. The GPS-PWV assimilation was extremely beneficial to improving the initial moisture analysis and heavy rainfall forecast within 3 hrs. The GPS-PWV data on variational data assimilation have provided more useful information to improve the predictability of precipitation for very short range forecasts.

Analysis of Nonlinear Destructive Interaction between Wind and Wave Loads Acting on the Offshore Wind Energy Converter based on the Hydraulic Model Test (해상 풍력발전체에 작용하는 풍하중과 파랑하중간의 비선형 상쇄간섭 해석 -수리모형실험을 중심으로)

  • Cho, Yong Jun;Yang, Kee Sok
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.27 no.5
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    • pp.281-294
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    • 2015
  • In order to quantitatively estimate the nonlinear destructive interaction of wave load with wind load, which is very vital for the optimal design of offshore wind energy converter, we carried out a hydraulic model test and wind tunnel test. As a substructure of offshore wind energy converter, we would deploy the monopile, which is popular due to its easiness in construction. Based on the simulation using Monte Carlo simulation using Kaimal spectrum and cross spectrum, the instantaneous maximum wind velocity is adjusted to 10 m/s. And, considering the wave conditions of the Western Sea where a pilot wind farm is planned to be constructed, $H_s=0.1m$, 0.15 m, 0.2 m is carefully chosen. It turns out that the nonlinear destructive interaction between the wind and wave loads acting on the offshore wind energy converter is more clearly visible at rough seas rather than at mild seas, which strongly support our deduction that a Large eddy, a swirling vortex developed near the bumpy water surface in the opposite direction of the wind, is the driving mechanism underlying nonlinear destructive interaction between the wind and wave loads.

Impact Assessment of Sea_Level Rise based on Coastal Vulnerability Index (연안 취약성 지수를 활용한 해수면 상승 영향평가 방안 연구)

  • Lee, Haemi;Kang, Tae soon;Cho, Kwangwoo
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.27 no.5
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    • pp.304-314
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    • 2015
  • We have reviewed the current status of coastal vulnerability index(CVI) to be guided into an appropriate CVI development for Korean coast and applied a methodology into the east coast of Korea to quantify coastal vulnerability by future sea_level rise. The CVIs reviewed includes USGS CVI, sea_level rise CVI, compound CVI, and multi scale CVI. The USGS CVI, expressed into the external forcing of sea_level rise, wave and tide, and adaptive capacity of morphology, erosion and slope, is adopted here for CVI quantification. The range of CVI is 1.826~22.361 with a mean of 7.085 for present condition and increases into 2.887~30.619 with a mean of 12.361 for the year of 2100(1 m sea_level rise). The index "VERY HIGH" is currently 8.57% of the coast and occupies 35.56% in 2100. The pattern of CVI change by sea_level rise is different to different local areas, and Gangneung, Yangyang and Goseong show the highest increase. The land use pattern in the "VERY HIGH" index is dominated by both human system of housing complex, road, cropland, etc, and natural system of sand, wetland, forestry, etc., which suggests existing land utilization should be reframed in the era of climate change. Though CVI approach is highly efficient to deal with a large set of climate scenarios entailed in climate impact assessment due to uncertainties, we also propose three_level assessment for the application of CVI methodology in the site specific adaptation such as first screening assessment by CVI, second scoping assessment by impact model, and final risk quantification with the result of impact model.