• Title/Summary/Keyword: depth ambiguity

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Parameter Mismatches and its Biases in Ocean Matched Field Processing (해양 정합장처리에서 매개변수 오정합과 바이어스)

  • Park Jae-Eun;Kim Jea-Soo;Shin Kee-Cheol
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.2
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    • pp.87-96
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    • 2005
  • In matched field processing (MEP), the observed acoustic field data is basically correlated with the replica produced by the modeling. therefore the results of source localization and correlation is limited by the mismatch of the environment and sensor location. In this paper. the effects of mismatch in environment and system on the bias in estimating the source location are investigated in the context of source localization. In the Pekeris waveguide, the simulation shows that the mismatches in environment and system, can cause a significant biases in the source localization and a degradation in MFP correlation. Mismatch caused by uncertainties in array tilt and depth, bottom depth, bottom sound speed, etc. causes degradation in source localization performance.

The Analysis of Resolution on the Image Reconstnlction Algorithms for Ultrasonic Diffraction Tomography (초음파 회절 토모그라피 영상복원 알고리즘의 분해능 분석)

  • 구길모;황기환
    • The Journal of the Acoustical Society of Korea
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    • v.18 no.5
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    • pp.83-90
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    • 1999
  • In this paper, we studied resolution to the FBP and BFP image reconstruction algorithms for ultrasonic diffraction tomography. In order to analyze the resolution to the tomographic images which can be reconstructed from the modified FBP image reconstruction algorithm by using fixed coordinate system and BFP image reconstruction algorithm which is suitable for plane structure object, we derived ambiguity functions to these algorithms and then analyzed lateral and depth resolution through simulation respectively. Simulation results show that the lateral and depth resolution to the FBP image reconstruction algorithm and the BFP image reconstruction algorithm was determined 0.27 λ, 0.70 λ and 0.39 λ, 0.98 λ at the 3dB respectively. These results imply that modified FBP and BFP image reconstruction algorithms for diffraction tomography is useful in the tomographic image reconstruction.

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Evaluation of intensity of 13 December 1996 Yeongweol earthquake and attenuation properties of Korean peninsula (1996년 12월 13일 영월지진의 진도평가와 한반도의 지진에너지감쇠 특성)

  • 조봉곤
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 1997.04a
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    • pp.21-26
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    • 1997
  • For 262 locations throughout the southern part of Korean peninsula, intensities of 13 December 1996 Yeongweol earthquake are estimated to make an isoseismal map and investigate attenuation properties in the southern part of Korea. Due to the inherent uncertainties in the estimation of intensities, obtained intensity map show quite scattered pattern of intensity distribution. Estimated intensities range from III to possibly Ⅷ. In case of intensity larger than Ⅵ, considerable damages such as fracturing of walls are reported one of the most significant feature of the intensity map is, considering its magnitude 4.7 reported by KMA, the felt area is appeared to be unusually large covering most of the Korean peninsula except Cheju island. This result indicates ether the magnitude is underestimated or the focus of this earthquake is much deeper. Assuming shallow(less than 10km) intraplate earthquake, we obtained average magnitude 5.6 by using the area encircled by isoseismal contour lines from intensity IV to intensity Ⅶ. This ambiguity can be clarified if more reliable focal depth is estimated by using teleseismic earthquake records in the future.

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Analysis of Coast Topography by RTK GPS and Echo Sounder

  • Lee, Jea-One;Kim, Jin-Soo
    • Korean Journal of Geomatics
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    • v.2 no.1
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    • pp.57-64
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    • 2002
  • Measuring the depth of water is very important in ensuring the protection and safety of seaside. There are many difficulties in making the contour bathymetric map, and contour line due to the limitation of continuous measurement of water depth and collimation with the conventional measuring and positioning methods. But the real-time kinematic GPS (RTK GPS) positioning using a carrier phase enables us to decide a precise position without breaking a signal even under the condition of a moving environment. It is also possible to obtain an accurate depth of water in real time with a fathometer through the measuring of time delay between sending and receiving epochs. This research aims at investigation of accuracy potential of RTK GPS in combination with Echo Sounder(E/S) for the coastal mapping. Apart from this purpose, the accuracy of ambiguity resolution with the OTF(On the Fly) method was tested with respect to the initialization time. The result shows that the accuracy is better than 1cm with 5-minute initialization in the distance of 10km baseline. The seaside topography was measured by the RTK GPS only, on the other hand the seafloor topography was surveyed in combination of RTK GPS and E/S. Comparing to the volume of seaside measured by RTK GPS and digital topographical map, the difference of only 2 % was achieved. This indicates that the coastal mapping with RTK GPS is successfully conducted. In addition it is also demonstrated that the 3-dimensional perspective model resulted from the undersea topography measured by RTK GPS and E/S is very close to that from the digital map. Through this study, it was verified that RTK GPS is to be very useful method in the analysis of coastal morphology owing to its capability of getting the precise DTM for the using of harbor reclamation, dredging, and the estimation of soil movement in a river.

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Advertisement Criticism through Audience Response and Communication Efficacy - focused on KT&G TV-CM text - (수용자 반응 중심의 광고비평과 커뮤니케이션 실효성 - KT&G TV광고 텍스트를 중심으로 -)

  • Lee, Hyun-Woo
    • Archives of design research
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    • v.19 no.5 s.67
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    • pp.233-242
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    • 2006
  • The purpose of this study is to investigate communication efficacy of advertisement text through audience responses. This study approached qualitatively to KT&G TV commercials. The research proceeded as follows: First, as background theory, studies on audience focusing advertisement criticism and the interpretation of advertising texts were reviewed. Secondly, the characteristics of the audiences of the advertisements, analyzed through in-depth individual interviews as well as group interviews, were incorporated into a broad theme and then divided into different dimensions. Finally, the audiences' decoding code and critic reponses in reading ambiguous advertising texts, and the interrelationship between strategic ambiguity were discussed under a unified model. The major findings of this study are as follows: In interpreting the ambiguous advertising texts, the audiences use various decoding codes such as language, visuals, technology and rhetoric, and various critic responses such as linguistic, macroscopic, schematic, non-verbal and socio-cultural factors, in quite comprehensive manner. Also, it was shown that audiences make use of different decoding strategies in terms of their recognition, reliability, emotional attitude, and behavior. It can therefore be concluded that the strategic ambiguity has its limit in explaining its effectiveness in the entire dimensions of recognition, emotional attitude, and behavior, in the sense that the strategic ambiguity is most effective in recognition while it invokes more negativity in the behavioral dimension. Finally, this empirical study, focusing on qualitative analyses, may have its limit as well; however, deeper statistic-qualitative studies in the future could compensate for it.

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The Effects of Emotional Labor on Job Stress and the Professional Identity of Sports Coaches for People with Disability (장애인스포츠지도자의 감정 노동이 직무스트레스 및 전문 직업 정체성에 미치는 영향)

  • Hong-Young Jang;Seung-Deuk Roh
    • Journal of Industrial Convergence
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    • v.21 no.5
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    • pp.123-132
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    • 2023
  • The purpose of this study is to examine the effects of emotional labor on job stress and the professional identity of sports coaches for people with disability. 190 surveys targeting sports coaches for people with disability working at sports associations for people with disability, rehabilitation sports centers, and welfare centers for people with disability in the metropolitan area were collected and used for analysis. Using the SPSS 22.0 statistical program, the collected data were subjected to frequency analysis, correlation analysis, and multiple regression analysis. As a result of the study, it was confirmed that emotional dissonance, a sub-factor of emotional labor, affects role ambiguity and role overload in job stress. The expression diversity, a sub-factor of emotional labor, had an impact on publicity, use of professional organizations, and sense of responsibility, which were sub-factors of professional identity. It was confirmed that emotional dissonance affects the autonomy of professional identity and the sense of responsibility. It was also confirmed that role ambiguity, a sub-factor of job stress, had an effect on professional identity, and that role overload had an effect on publicity and autonomy. As a follow-up, a detailed in-depth study including perceptions and thoughts on the types of emotional labor of sports coaches for people with disability according to national regions and categories other than metropolitan areas is needed.

A Heuristic Metric for Measuring Complexity of Class Inheritance Structures (클래스 상속구조에 대한 경험적 복잡성 척도)

  • Chung, Hong;Kim, Tae-Sik
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.4
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    • pp.328-333
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    • 2002
  • The deeper the hierarchy of a inheritance structure is, the better the reusability of the structure is, but the more difficult the understandability and the maintainability of it is. On the contrary, the shallower the hierarchy is, the worse the abstraction of the inheritance structure is, but the better the understandability and modifiability of it is. Therefore, it is to be desired that a deep hierarchy of a inheritance structure should be split to be shallow for the maintainability of a system. This paper proposed a complexity metric that is based on DIT and NOC of Chidamber and Kemerer, and solved the ambiguity of the metrics of them, which was pointed out by Li. The metric is a simple and heuristic one for measuring the complexity of class inheritance structures by considering the number of ancestor classes and descendant classes and the depth of inheritance hierarchy. This provides a quantitative information for assessing the complexity of a inheritance structure in splitting it.

An in-depth Interview Study to Examine the Performance Status of the Legal Risk Assessment of Musculoskeletal Disorders (근골격계부담작업 유해요인조사 이행 실태 파악을 위한 심층 면담 조사)

  • Jung, Hwa-Shik;Kee, Do-Hyung;Lee, In-Seok;Park, Jae-Hee
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.1
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    • pp.275-283
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    • 2011
  • The purpose of this study is to investigate the performance status of the ligal examination of risk factors of musculoskeletal disorders(MSDs). The study was based on in-depth interviews with the persons in charge of the examination in 63 sampled companies, which are various in location, type of industry and size. The interviews were carried out based on detail questions as well as a predefined checklist. The main findings are as follows: 1) More than half of the companies did not properly comply with the laws in performing the examination of MSDs risk factors; 2) In about 60% of the companies, the examination has been carried out by their own persons; 3) 38% of the companies conducting the survey of musculoskeletal symptoms did not diagnosed musculoskeletal symptoms based on the survey; 4) Most companies performed the prevention activities for MSDs such as education/training, stretching, etc.; 5) It was revealed that the 11 high-risk tasks were not considered to be properly defined by the people in the industries, which results in some difficulties such as ambiguity in defining the 11 tasks and unit tasks; 6) The period of the examination of risk factors, classification of periodic and occupational examinations and legalization of employers' obligation for preventing MSDs are considered to be acceptable or desirable, while it was pointed out that regulations for the method of the risk assessment and the person who in charge of the examination need to be modified.

Ambivalence Expressed in Contemporary Fashion (현대복식에 나타난 양면감정)

  • 김인숙
    • Journal of the Korean Society of Costume
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    • v.50
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    • pp.97-118
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    • 2000
  • The purposes of the present research were (1) to investigate the sociological factors influencing the increase of ambivalence and the relationship between, the ambivalence and fashion change(2) to categorize sets of the ambivalence expressed for contemporary fashion and (3) to examine the frequency and the patterns of ambivalence presented for contemporary fashion. This research was conducted through in depth literature review and content analysis. Data was collected from 806 colored pictures presented on 'Collections' from 1972 to 1988. Eight types of clothing cues were incluede: look color texture decorative motifs of clothing collar sleeve and wearer's headdress/hair style and make-up. The results of this study were as follows: 1 The popularization of culture has been accelerated by mass production mass consumption and mass media. Since the 1980s postmodernism and poststructuralism have resulted in the breakdown of dualistic distinction. As the ambiguity of meaning in appearance increases the meaning is negotiated constantly for identity. 2. The most frequenctly expressed ambivalence in clothing was feminity/masculinity and tradition/modernity and wealth/poverty was the least. The number of ambivalent expression were the highest during 1990s. The rapid growth in ambivalence of tradition/modernity was found in 1970s feminity/masculinity in 1980s and modesty/immodesty in 1990s. Within a clothing style ambivalence was manifested through feminine look in white for beauty/ugliness feminine look mainly in yellow/red for wealty/poverty sexy look dominantly in black for modesty/immodesty androgynous look in black for feminity/masculinity and through ecology look most frequently in black for tradition/modernity.

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Vulnerability Evaluation Methodology for firewall Certification (침입차단시스템 제품 인증을 위한 취약성 평가 방법)

  • 김점구
    • The Journal of Information Technology
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    • v.3 no.3
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    • pp.27-37
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    • 2000
  • Although an insurance criterion for reliance is unified, the difference in evaluation mechanism in every country is already ambiguity. In other words, the aspect of objectivity would be a little because it is true that the vulnerability evaluation include evaluator, scenario and tools (TSVES) applying in test, depth and scope of evaluation. But evaluation results can be difference in accordance with each evaluation elements. By using TSVES to evaluating network security vulnerability, first, we expected the evaluation results is impartiality, objectivity, repeatability, reproducibility, appropriateness and soundness of results. Second, it could be transferred manual ways into automation ways, and then expected easiness and safety of extension and modification in a quality of products as well as a dramatical reduction of waste of time and energy.

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