• Title/Summary/Keyword: representativeness

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Test and estimation of ballistic armor performance for recent naval ship structural materials

  • Shin, Yun-ho;Chung, Jung-hoon;Kim, Jong-Hwan
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.10 no.6
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    • pp.762-781
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    • 2018
  • This paper presents the ballistic armor performance examination and thickness estimation for the latest naval ship structure materials in the Republic of Korea. Up to date, research regarding methods of ballistic experiments establishing database on the latest hull structure materials as well as a precise method of estimating required thickness of armor against specific projectiles have been rarely researched. In order to build a database and estimate proper thicknesses of structure materials, this study used four structure materials that have been widely applied in naval ships such as AH36 steel, AL5083, AL5086, and Fiber Reinforced Plastics (FRP). A $7.62{\times}39mm$ mild steel core bullet normally fired by AK-47 gun was considered as a threat due to its representativeness. Tate and Alekseevskii's penetration algorithm was also used to calculate a correction factor (${\alpha}$) and then estimate the armor thickness of naval ship hull structure materials with a given impact velocity. Through live fire experiments, the proposed method performance difference was measured to be 0.6% in AH36, 0.4% in AL5083, 0.0% in AL5086, and 8.0% in FRP compared with the experiment results.

Ventilation Measurement with PFT in Three-storied Detached House (PFT법에 의한 수직적 3 ZONE 분할 조건에서의 환기량 측정)

  • Kim, Hoon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.25 no.9
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    • pp.506-515
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    • 2013
  • The PFT (PerFluorocarbon Tracergas Technique) is of advantage to field surveys for evaluating the ventilation condition, due to its simplicity and convenience. On the other hand, it requires researchers to make some additional considerations that include uncertainties, such as the substance concentration distribution in indoor air, representativeness of a sampler, deviation of emission sources, and analysis error. In this study, the PFT and $CO_2$ tracer gas methods were applied simultaneously, to evaluate the accuracy of PFT on six ventilation conditions in the three-storied detached house. The air exchange and the outdoor air introduction a between and into zones were measured. As the results, deviations of PFT concentration distributions were observed at a sufficiently low level for an accurate determination for a house where the interior height was large, and there were relatively many partition walls. However, when a uniform airflow appeared in the indoor air, it was also validated that the indoor air would be exhausted without sufficient mixing, and consequently the measurement error of the PFT would be large.

Strategies for the Development of Tourism Resources in the Inland Waters for the Revitalization of Special Tourist Zone - Focus on value frame analysis - (관광특구 활성화를 위한 내수면 관광자원화 전략 -가치프레임 분석을 중심으로-)

  • Cho, Si-Young;Lee, Kwang-Kug;Jun, Jae-Kyoon;Yhang, Wii-Joo
    • The Journal of Fisheries Business Administration
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    • v.50 no.3
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    • pp.59-71
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    • 2019
  • In terms of coastal and marine tourism, Busan's Haeundae had the nation's representativeness, and is pushing for many kinds of related policies to revitalize the special tourism zone. Due to a drop in the number of beach users, it is inevitable for the Haeundae Special Tourist Zone to face active responses to new trends emerging in the global tourism market. Therefore, the purpose of this study is to present a tourism strategy for making the Suyeong River as a more competitive ourist resource along the zone. First, a language network analysis is conducted through interviews to understand the ideas of interest groups for the river cruise activation project. Second, the frame structure of stakeholders is used to analyze solutions by comparing the similarities and differences in recognition frames of interest groups. Third, we intend to analyze the detailed frame types of stakeholders and present new alternatives based on the structure of relationships between types.

DA-Res2Net: a novel Densely connected residual Attention network for image semantic segmentation

  • Zhao, Xiaopin;Liu, Weibin;Xing, Weiwei;Wei, Xiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.11
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    • pp.4426-4442
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    • 2020
  • Since scene segmentation is becoming a hot topic in the field of autonomous driving and medical image analysis, researchers are actively trying new methods to improve segmentation accuracy. At present, the main issues in image semantic segmentation are intra-class inconsistency and inter-class indistinction. From our analysis, the lack of global information as well as macroscopic discrimination on the object are the two main reasons. In this paper, we propose a Densely connected residual Attention network (DA-Res2Net) which consists of a dense residual network and channel attention guidance module to deal with these problems and improve the accuracy of image segmentation. Specifically, in order to make the extracted features equipped with stronger multi-scale characteristics, a densely connected residual network is proposed as a feature extractor. Furthermore, to improve the representativeness of each channel feature, we design a Channel-Attention-Guide module to make the model focusing on the high-level semantic features and low-level location features simultaneously. Experimental results show that the method achieves significant performance on various datasets. Compared to other state-of-the-art methods, the proposed method reaches the mean IOU accuracy of 83.2% on PASCAL VOC 2012 and 79.7% on Cityscapes dataset, respectively.

Ways of (Un)Seeing Race and History in Clint Eastwood's Revisionist Western Unforgiven

  • Kim, Junyon
    • English & American cultural studies
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    • v.10 no.2
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    • pp.29-48
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    • 2010
  • This paper is a kind of interdisciplinary studies which connect a Western film criticism with a criticism of minority literature in America. My purpose in this paper is to put on the table such a sensitive issue as racial representation and representativeness in Clint Eastwood's revisionist Western, Unforgiven. We admit generally that Western films have contributed to the white American myth-making of how the West was won. Yet, since the mid-1960s, a growing number of revisionist Westerns were produced so as to raise a question about the conventional way of looking at what happened in the American West. In order to analyze the problem inherent in the way of seeing, I pay attention to how the director Eastwood (re)presents a character named W. W. Beauchamp in the film. Presumably, what the character Beauchamp misses in the West can be overlapped with what ordinary film viewers miss in the genre of Westerns. Given this, interrogating both what Beauchamp sees and what he misses within the movie, I attempt to disclose how much of the West has been unseen from his biased viewpoint. By doing so, I argue why it is important to focus on some passing scenes that touch on the irony of a Native American train passenger, the gaze of the mute Native American housewife, the abrupt disappearance of Asian American men, the lynching of African-American ex-cowboy, and the self-determination of the saloon prostitutes. Then I hope that, conservative and mainstream though the director is, his way of revising the Western is not quite far from my minority-conscious critical position.

Soil sampling plan design of key facilities for denuclearization based on data quality objective process

  • Jeon, Yeoryeong;Kim, Yongmin
    • Nuclear Engineering and Technology
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    • v.54 no.10
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    • pp.3788-3794
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    • 2022
  • The possibility of denuclearization of the Korean Peninsula has been continuously debated, and the initiative participation of the Republic of Korea has necessitated preemptive measures against neighboring countries. In this study, we present a proposal for formulating a site survey plan when the amount of site information provided is insufficient and the accuracy of the information is not guaranteed. Considering a case wherein "a soil sample analysis is used to determine the presence or absence of nuclear activity" in a radiochemical laboratory, which is a typical key facility for denuclearization, the optimal soil sample collection plan is designed based on international guidelines and public information. In the event of denuclearization, a scenario that is not based on the expertise of the sample collector is set, and the data quality objective (DQO) process is applied to ensure reality. Consequently, the primary sample collection points can be derived in consideration of accessibility, and the sample collection scale can be adjusted according to the cost. By applying the DQO process to ensure sample representativeness and reality, reliable and resource-efficient soil sample collection can be achieved in radiochemical laboratories and other denuclearization facilities.

Qualitative Literature Analysis: The Meaningful Association between ESG Management and Economic Development

  • Anthony NJUGUNA;Phouthakannha NANTHARATH;Eungoo KANG
    • The Journal of Industrial Distribution & Business
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    • v.15 no.5
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    • pp.29-37
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    • 2024
  • Purpose: Numerous prior researchers have identified only that sustainable management of ESG factors promotes business value creation and shapes enhanced innovation performance. This study aims to determine the positive relationships between ESG management and economic development, focusing on the mutual benefits and risks and the various stakeholders involved in managing change. Research design, data and methodology: This study selected the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement as a key methodology. Literature search used the following databases: Web of Science, Scopus, and Google Scholar. The quality assessment criteria for selected prior studies ranged from issues like design, sample size and the representativeness of the subjects, validity of measurements, and analytical strength. Results: The findings of this study indicates that there are four critical solutions for economic development triggers using ESG strategy, such as (1) ESG and Innovation-Driven Growth, (2) ESG and Human Capital Development, (3) ESG and Operational Efficiency, (4) ESG and Market Opportunities. This study insists that public-private partnerships are critical for enhancing sustainable economic development and meeting the needs of society. Conclusions: It is, therefore, important for governments and policymakers to play a critical role in setting the proper framework that allows for the uptake of ESG and an enabling environment for sustainable economic development.

Overview of the Development of the Korean Exposure Factors Handbook

  • Jang, Jae-Yeon;Jo, Soo-Nam;Kim, So-Yeon;Myung, Hyung-Nam
    • Journal of Preventive Medicine and Public Health
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    • v.47 no.1
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    • pp.1-6
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    • 2014
  • A set of exposure factors that reflects the characteristics of individual behavior capable of influencing exposure is essential for risk and exposure assessment. In 2007, the Korean Exposure Factors Handbook was, therefore, issued, driven by the need to develop reliable exposure factors representing the Korean population. The purpose of this study was to overview the development process of the Korean Exposure Factors Handbook and major recommended exposure values for the Korean population to allow information exchanges and comparison of recommended values among nations. The researchers reviewed the domestic data that could be used in the development of exposure factors, confirmed a knowledge gap, and set a priority of development by phases. A methodology to measure exposure factors was established to develop measuring techniques and test their validity. Data were processed or a survey was conducted according to the availability of data. The study thus produced recommended values for 24 exposure factors grouped by general exposure factors, food ingestion factors, and activity factors by setting up a database of exposure factors and carrying out statistical analysis. The study has significantly contributed to reducing the potential uncertainty of the risk and exposure assessment derived by the application of foreign data or research findings lacking representativeness or grounds by developing a set of exposure factors reflecting the characteristics of the Korean people. It will be necessary to conduct revisions in light of the changing statistical values of national data and the exposure factors based on Korean characteristics.

An Overview of Exit Polls for the 2006 Local Elections (2006년 지방선거 출구조사 현황 및 예측오차)

  • Kim, Ji-Hyeon;Kim, Young-Won
    • Survey Research
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    • v.8 no.1
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    • pp.55-79
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    • 2007
  • This article attempts to provide an overview of the exit polls for the 2006 local elections in Korea. The sampling method, sampling error, non-response rate, and prediction error of the exit polls are reviewed. Also, we explore the fact that the propensity to vote varies according to age and gender of voters. In terms of age and gender, the representativeness of the sample is investigated by comparing to the data released by the National Election Commission. Through this empirical research, we show that the exit poll samples are unbalanced in terms of age and this unbalance may be one of the causes of bias occurred in the prediction of the 2006 local election results. The design effects of the sample design implemented for the exit polls are also examined.

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Uncertainty of Online TOC Analyzer in Water Quality Monitoring System (수질자동측정시스템에서 온라인 TOC 자동측정장치의 불확도 산출)

  • Lee, Chung-Yul;Lee, Yong-Woon;Lee, Jun-Hung;Lim, Boung-Jin;Kwon, Young-Jin;Khang, Bum-Ju;Hong, Young-Min
    • Korean Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.193-200
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    • 2007
  • The objective of this study was to estimate uncertainty of online TOC analyzer in water quality monitoring system. A procedure for the estimation of measurement uncertainty of total organic compounds (TOC) based on the ISO approach is presented. It is based on a mathematical model that involves 4 input parameters (standardization, sensitivity, solute effect and representativeness). In this study, a major problem in estimating the uncertainty of online TOC analyzer was the solute effect. It was strongly depends on organic materials. So homogeneity of the sample is the most important consideration. Modified concentration and combined standard uncertainty was $4.71{\pm}0.36$ mg $L^{-1}$ by model modified in this study.