• Title/Summary/Keyword: data analysis: surveys

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Application of DC Resistivity Survey from Upper Portion of Concrete and Geostatistical Integrated Analysis (콘크리트 상부에서 전기비저항 탐사 적용 및 지구통계학적 복합 해석)

  • Lee, Heuisoon;Oh, Seokhoon;Chung, Hojoon;Noh, Myounggun;Ji, Yoonsoo;Ahn, Taegyu;Song, Sung-Ho;Yong, Hwan-Ho
    • Journal of the Korean earth science society
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    • v.35 no.1
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    • pp.29-40
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    • 2014
  • A DC resistivity survey was performed to detect anomalies beneath concrete pavement. A set of high conductive media and planar electrodes were used to lessen the effect's a high contact resistance of concrete. Results of the resistivity survey were analyzed and compared with those of other geophysical surveys such as Ground Penetration Radar (GPR), Impulse Response (IR), and Multi-channel Analysis of Surface Waves (MASW), which were carried out in the same location. The results of resistivity survey showed a high resistive distribution in the section of sink and pavement where a pattern of reinforcement was observed through the GPR survey. Also, a comparison of results between the IR and resistivity surveys indicated that the high resistivity was produced by the high dynamic stiffness in the reinforced section. The co-Kriging of both the results of DC resistivity and MASW surveys at the same location showed that an integrated geostatistical analysis is able to give more accurate description on the anomalous subsurface region than can a separate analysis of each geophysical approach. This study suggests that the integrated geostatistical approaches were used for a decision-making process based on the geophysical surveys.

Sensitivity analysis of missing mechanisms for the 19th Korean presidential election poll survey (19대 대선 여론조사에서 무응답 메카니즘의 민감도 분석)

  • Kim, Seongyong;Kwak, Dongho
    • The Korean Journal of Applied Statistics
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    • v.32 no.1
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    • pp.29-40
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    • 2019
  • Categorical data with non-responses are frequently observed in election poll surveys, and can be represented by incomplete contingency tables. To estimate supporting rates of candidates, the identification of the missing mechanism should be pre-determined because the estimates of non-responses can be changed depending on the assumed missing mechanism. However, it has been shown that it is not possible to identify the missing mechanism when using observed data. To overcome this problem, sensitivity analysis has been suggested. The previously proposed sensitivity analysis can be applicable only to two-way incomplete contingency tables with binary variables. The previous sensitivity analysis is inappropriate to use since more than two of the factors such as region, gender, and age are usually considered in election poll surveys. In this paper, sensitivity analysis suitable to an multi-dimensional incomplete contingency table is devised, and also applied to the 19th Korean presidential election poll survey data. As a result, the intervals of estimates from the sensitivity analysis include actual results as well as estimates from various missing mechanisms. In addition, the properties of the missing mechanism that produce estimates nearest to actual election results are investigated.

Surface Wave Method: Focused on Active Method (표면파 탐사: 능동 탐사법을 중심으로)

  • Kim, Bitnarae;Cho, Ahyun;Cho, Sung Oh;Nam, Myung Jin;Pyun, Sukjoon;Hayashi, Koich
    • Geophysics and Geophysical Exploration
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    • v.22 no.4
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    • pp.210-224
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    • 2019
  • Surface wave (SW) surveys, which have been applied to numerous application fields ranging from micro-scale ultrasonic analysis to geological scale analysis, are widely used to monitor near-surface stability. The survey method is basically made through analysis on dispersion of SW propagating along the earth surface, in order to delineate shear velocity structure of subsurface. SW survey data are inverted with assuming one-dimensional (1D) layered-earth in order to recover shear wave velocities of each layer, after being analyzed to make the dispersion curve that shows phase velocity of SW with respect to frequency. This study reviews surface wave surveys with explaining the basic theory including the characteristics of dispersion and the procedure of general data processing. Even though surface wave surveys can be categorized into active and passive methods, this paper focuses only on active surface wave methods which includes continuous SW (CSW), spectral analysis of SW (SASW) and multichannel analysis of SW (MASW). Passive method will be reviewed in the subsequent paper.

The Effects of Destination Regeneration on Revisit Intention: Moderating Roles of Destination Image

  • Woo-Hyuk Kim;Jae-Ho Choi
    • Asia-Pacific Journal of Business
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    • v.13 no.4
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    • pp.1-10
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    • 2022
  • Purpose - Despite the emergence of such destination regeneration as a key factor in urban tourism, little research was carried out on destination regeneration, especially on the impact of destination regeneration on revisit intention. The purpose of this study is to investigate the relationship between destination regeneration and revisit intention with moderating role of the destination image. Design/Methodology/Approach - Data were collected from tourists who visited the destination, after which a total of 250 usable surveys were analyzed. In order to examine the data, we used frequency analysis, exploratory factor analysis, regression analysis by using SPSS 25.0. Findings - Based on the results, first, there is a positive relationship between destination regeneration and revisit intention. In addition, there are significant moderating effects of destination image between destination regeneration and revisit intention. Research Implications or Originality - Those significant findings could contribute to destination development from destination regeneration and revisit intention.

Trends in Technology Roadmap and Exploration of Emerging Technologies for Leading R&D Planning (선도적 R&D 기획을 위한 기술로드맵 및 미래 유망기술 탐색 동향)

  • Y.H. Choi;K.D. Kim;H.S. Chung
    • Electronics and Telecommunications Trends
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    • v.39 no.2
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    • pp.93-102
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    • 2024
  • As the scale of research and development (R&D) increases, countries and companies are consistently establishing R&D directions to meet strategic goals and market demands as well as roadmaps to increase efficiency through concentration and selection. However, establishing an effective roadmap and discovering promising technologies are challenging under the current numerous technological possibilities and uncertainties. The importance of discovering promising technologies to secure future technological competitiveness is recognized worldwide, and Europe, the United States, and Japan are establishing processes to identify promising future technologies and support related R&D. Methods for discovering promising future technologies can be classified into future social needs analysis, forecasting, surveys, use of expert opinions, and data analysis. We describe the types and limitations of technology roadmaps and investigate the status of domestic and foreign organizations using weak signal search through quantitative data analysis.

AN ANALYTICAL ASSESSMENT OF THE SINKING OP THE M.V. DERBYSHIRE

  • Faulkner, D.
    • Journal of Ship and Ocean Technology
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    • v.6 no.4
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    • pp.19-76
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    • 2002
  • The author was appointed by the UK Department of Transport as a fellow Assessor with R. A. Williams during Lord Donaldson's Assessment (1995) of the loss of the OBO ship DERBYSHIRE and in 1996 as a UK Assessor for the planning and surveys of the wreck. He relinquished his appointment in October 1997 and was not thereafter Involved in the review and analysis of data gathered. This paper may be considered to be complementary to the reports of the UK and EC Assessors (Williams and Torchio, 1998a and 1998b) which followed that review and analysis. The paper deals with the history and loss of the ship, Including the concept developed in 1995 of 13 possible loss scenarios in a formal safety Risk Matrix of probability and seriousness. It analyses abnormal wave effects on hatch cover collapse, on ship bending, and on flooding of bow spaces and no. 1 hold. The implosion-explosion mechanics during sinking is outlined to explain the devastation of the wreck. The 1996 and 1997 underwater surveys are outlined as are the findings of fact. Each of the final 14 loss scenarios is analysed in the light of the firm and circumstantial survey evidence, plus many other factors of survey experience, analyses and experiments. The updated Risk Matrix speaks for itself and leads to the prime conclusions and major recommendations.

A Study on the Survey Method of the Residents′ Housing Needs Using Interactive Media - Focused on the Difference Analysis of Answer Disposition by Media - (인터랙티브 미디어를 이용한 거주자 요구 조사방법에 관한 연구 1 - 매체별 응답성향 차이분석을 중심으로 -)

  • 김석태;오찬옥;박수빈;양세화
    • Korean Institute of Interior Design Journal
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    • v.13 no.5
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    • pp.114-124
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    • 2004
  • Most previous studies, in general, related to housing needs have analyzed the data from self-administered survey or interview using questionnaire or simple 2D floor plan. This study was Intended to suggest how to increase the reliability and effectiveness of such survey methods in examining the residents' housing needs. In order to accomplish the purpose, the two kinds of surveys using Web based VR media and typical questionnaire were peformed. The same questions were used for these two surveys, and they included the furniture characteristics, use of each room, adjustment of room size, preferences for interior colors, preferred furniture in living room, space layout of floor plan, housing life style, and preference for housing characteristics. The answer differences between these two were analyzed. The subjects were 402 housewives who lived in apartment houses in Haeundae, Busan. Finding were as follows: first, the media method was more likely to be effective than typical questionnaire survey in explaining housing needs for the adjustment of room size in housing unit plan. Second, the media method was more realistic and reliable than the other in comprehending the needs for the interior colors. Last, the VR media tended to be more effective than the other in understanding the space layout of floor plan. This research sheds light on the utilization of visual instrument for the analysis of needs related to space use.

Effect of dental fear on dental use behavior and treatment need degree (치과공포가 치과이용행태 및 치료요구도에 미치는 영향)

  • Jun, Sung-Hee;Jung, Myung-Hee
    • Journal of Korean society of Dental Hygiene
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    • v.7 no.3
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    • pp.329-342
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    • 2007
  • This study was conducted in order to know whether DFS questionnaire which can measure dental fear is suitable for dental fear measuring method and to know effect of dental fear on dental use behavior and treatment need degree. This survey was conducted from May 1, 2007 to May 31, 2007. A total of 281 surveys eligible among all the collected surveys were used in the analysis. Collected data were analyzed by using SPSS 12.0. The obtained results were as follows: 1. Based on the reliability analysis, we concluded that the questionnaire of dental fear was reliable, and the Cronbach' s alpha coefficients of the all subscales were more than 0.6. 2. Among the dental fear of 3 factors, treatment fear cause stimulation factor was higher than the others. Most of all, following two situations(when preparation was made and when people hear dental instrument operating sound) are the highest in the treatment fear. And women are higher than men in every item. 3. In the Dental treatment need degree caused by dental fear degree, high fear group was $4.76{\pm}1.954(M{\pm}SD)$ which was higher than that of low fear group.(low fear group was $4.07{\pm}2.184(M{\pm}SD)$. In conclusion, dental fear and dental treatment need degree are related each other.

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Exploratory Study on the Process and Checklist Items for Construction Safety Inspection Utilizing Drones

  • Jung, Jieun;Baek, Mina;Yu, Chaeyeon;Lee, Donghoon;Kim, Sungjin
    • Journal of the Korea Institute of Building Construction
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    • v.23 no.3
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    • pp.327-336
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    • 2023
  • The focus of this research was to devise a conceptual methodology for drone usage and to assess the viability of safety checklist items specific to drone application in safety oversight. The appraisal was grounded in a focus group interview involving professionals from construction management and safety fields. The proposed process was segmented into four stages: 1) pre-flight phase for flight plan development, 2) drone flight phase for safety condition inspection utilizing checklist items, 3) post-flight phase for visual asset analysis, and 4) documentation and management phase. Furthermore, the research scrutinized the applicability of 32 distinct safety checklist items for drone operations. The primary aim of this investigation was to probe the possible deployment of drones as part of construction safety inspections at work sites. However, it bears mentioning that subsequent research should strive to gather a more extensive sample size through questionnaire surveys, thereby facilitating quantitative analysis. Administering such surveys would yield more comprehensive data compared to a focus group interview, which was constrained by a limited participant count. In summation, this study lays a foundational groundwork for understanding the potential advantages and challenges associated with integrating drones into construction safety management.

Estimating GHG Emissions from Agriculture at Detailed Spatial-scale in Geographical Unit (상세 공간단위 농업분야 온실가스 배출량 산정 방안 연구)

  • Kim, Solhee;Jeon, Hyejin;Choi, Ji Yon;Seo, Il-Hwan;Jeon, Jeongbae;Kim, Taegon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.65 no.5
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    • pp.69-80
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    • 2023
  • Carbon neutrality in agriculture can be derived from systematic GHG reduction policies based on quantitative environmental impact analysis of GHG-emitting activities. This study is to explore how to advance the calculation of carbon emissions from agricultural activities to the detailed spatial level to a spatial Tier 3 level (Tier 2.5 level), methodologically beyond the Tier 2 approach. To estimate the GHG emissions beyond the Tier 2.5 level by region for detailed spatial units, we constructed available activity data on carbon emission impact factors such as rice cultivation, agricultural land use, and livestock. We also built and verified detailed data on emission activities at the field level through field surveys. The GHG emissions were estimated by applying the latest national emission factors and regional emission factors according to the IPCC 2019 GL based on the field-level activity data. This study has significance that it explored ways to build activity data and calculate GHG emissions through statistical data and field surveys based on parcels, one of the smallest spatial units for regional carbon reduction strategies. It is expected that by utilizing the activity data surveyed for each field and the emission factor considering the activity characteristics, it will be possible to improve the accuracy of GHG emission calculation and quantitatively evaluate the effect of applying reduction policies.