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Considerations and Alternative Approaches to the Estimation of Local Abundance of Legally Protected Species, the Fiddler Crab, Austruca lactea (법정보호종, 흰발농게(Austruca lactea) 서식 개체수 추정에 대한 검토와 대안)

  • Yoo, Jae-Won;Kim, Chang-Soo;Park, Mi-Ra;Jeong, Su-Young;Lee, Chae-Lin;Kim, Sungtae;Ahn, Dong-Sik;Lee, Chang-Gun;Han, Donguk;Back, Yonghae;Park, Young Cheol
    • Journal of Wetlands Research
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    • v.23 no.2
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    • pp.122-132
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    • 2021
  • We reviewed the methods employed in Korean tidal flat surveys to measure the local abundance of the endangered wildlife and marine protected species, the fiddler crab, Austruca lactea. A complete census for infinite population is impossible even in a limited habitat within a tidal flat, and density estimates from samples strongly vary due to diverse biological and ecological factors. The habitat boundaries and areas shift with periodicities or rhythmic activities of organisms as well as measurement errors. Hence the local abundance calculated from density and habitat areas should be regarded as transient. This conjecture was valid based on the spatio-temporal variations of the density averages, standard error ranges, and spatial distribution of the crab, A. lactea observed for 3 years (2015-2017) in Songdo tidal flat in Incheon. We proposed the potential habitat areas using the occurrence probability of 50% from logistic regression model, reflecting the importance of habitat conservation value as an alternative to local abundance. The spatial shape of potential habitat predicted from a generalized model would remain constant over time unless the species' critical environmental conditions change rapidly. The species-specific model is expected to be used for the introduction of desired species in future habitat restoration/creation projects.

Seismic investigation of cyclic pushover method for regular reinforced concrete bridge

  • Shafigh, Afshin;Ahmadi, Hamid Reza;Bayat, Mahmoud
    • Structural Engineering and Mechanics
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    • v.78 no.1
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    • pp.41-52
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    • 2021
  • Inelastic static pushover analysis has been used in the academic-research widely for seismic analysis of structures. Nowadays, the variety pushover analysis methods have been developed, including Modal pushover, Adaptive pushover, and Cyclic pushover, in which some weaknesses of the conventional pushover method have been rectified. In the conventional pushover analysis method, the effects of cumulative growth of cracks are not considered on the reduction of strength and stiffness of RC members that occur during earthquake or cyclic loading. Therefore, the Cyclic Pushover Analysis Method (CPA) has been proposed. This method is a powerful technique for seismic evaluation of regular reinforced concrete buildings in which the first mode of them is dominant. Since the bridges have different structures than buildings, their results cannot necessarily be attributed to bridges, and more research is needed. In this study, a cyclic pushover analysis with four loading protocols (suggested by valid references) by the Opensees software was conducted for seismic evaluation of two regular reinforce concrete bridges. The modeling method was validated with the comparison of the analytical and experimental results under both cyclic and dynamic loading. The failure mode of the piers was considered in two-mode of flexural failure and also a flexural-shear failure. Along with the cyclic analysis, conventional analysis has been studied. Also, the nonlinear incremental dynamic analysis (IDA) method has been used to examine and compare the results of pushover analyses. The time history of 20 far-field earthquake records was used to conduct IDA. After analysis, the base shear vs. displacement in the middle of the deck was drawn. The obtained results show that the cyclic pushover analysis method is able to evaluate an accurate seismic behavior of the reinforced concrete piers of the bridges. Based on the results, the cyclic pushover has proper convergence with IDA. Its accuracy was much higher than the conventional pushover, in which the bridge piers failed in flexural-shear mode. But, in the flexural failure mode, the results of each two pushover methods were close approximately. Besides, the cyclic pushover method with ACI loading protocol, and ATC-24 loading protocol, can provided more accurate results for evaluating the seismic investigation of the bridges, specially if the bridge piers are failed in flexural-shear failure mode.

The Effect of Car-Free Pedestrian Street Policy on Urban Vibrancy Using Synthetic Control Method (통제집단합성법을 활용한 차 없는 거리 정책의 도시 활력 증진 효과 분석)

  • Ha, Jungwon;Ha, Jaehyun;Lee, Sugie
    • Journal of the Korean Regional Science Association
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    • v.38 no.2
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    • pp.59-72
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    • 2022
  • In line with increasing interest of climate change and pedestrian rights, the city of Seoul has been implementing car-free pedestrian street policies. The government and the private sector agreed to introduce carfree streets, expecting to increase the urban vibrancy and attract customers in the streets. However, studies that empirically analyze the effects of the policy are insufficient, and there are no studies that reevaluate the car-free pedestrian street policy after the COVID-19 outbreak. Therefore, this study evaluates the car-free pedestrian street policy at the commercial street, the Jongno 52-gil, using the synthetic control method. As a result of the analysis, it was found that the car-free pedestrian street policy was valid for enhancing urban vibrancy. Also, it was found that proper time interval is required to assess the policy since the peak increase of policy was observed in 3 months after the policy implementation. However, less than a year, the increase of the de facto population density on the Jongno 52-gil was revealed to be insignificant. In addition, the Jongno 52-gil was more vulnerable in the decrease of the de facto population density in the COVID-19 period than the synthetic control region. The results of this study suggest that long-term population inflow measures and flexible counterplan to contagious diseases are necessary in the car-free pedestrian street policy.

Wild Ginseng Digger's Digging Custom and Its Special Servitude of Korean Civil Act (산삼 심마니 채삼 관습과 민법상 특수지역권)

  • Byungil Bae
    • Journal of Ginseng Culture
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    • v.5
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    • pp.77-96
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    • 2023
  • This study looks at the origin of a wild-ginseng, Korean ginseng, and traces the origin of associated wild-ginseng digging customs back to the Annals of the Joseon Dynasty. These historical customs helped Korea gain control over its wild ginseng resources following Japanese colonization acts, Korea's present-day forest laws, and Korean Civil Law. Prior to Japanese colonial rule in Korea (1910-1945), ginseng digging was a common custom, but Imperial Japan distorted Korea's own legal principles of the public rights of wild-ginseng digging during this colonial period. Distorted legal principles concerning digging customs continued after Korea's liberation from Japanese rule and were maintained until the enforcement of the Korean Civil Law in 1960, when legal principles of the right of common were changed to special servitude. The origin of the right of common can be found in the Sichojang of the Joseon Dynasty. The Sichojang, a place where local residents jointly collected firewood and fed livestock, was the minimum right to life and interest at the time. Since the right of common was the right to life, Imperial Japan attempted to abolish it, but it was never successful. In addition, distorted legal principles have been maintained in present-day forestry-related laws and regulations. Over 75 years since the liberation from Japanese rule in 1945, it is imperative to break away from the distorted legal principles and acknowledge that digging custom rights have changed from common customs to a special servitude under Korean Civil Law. Hence, an organization of wild-ginseng diggers is an unincorporated association, and their wild-ginseng digging customs can be constituted as a special servitude. Hence, their practices should be considered valid under customary law. Through this, it will be possible to clarify the legal nature and grounds for ginseng-related wild-ginseng digging activities, as well as the civil responsibility for the activities of wild-ginseng diggers.

A Study on the Reliability and Validity of the Collection of the Ethnography Method of Service Experience Data - Focusing on I know You_AI Service - (서비스경험데이터의 에스노그라피 방식 수집에 대한신뢰성과 타당성 연구 - I know you_AI 서비스를 중심으로 -)

  • Ahn, Jinho;Lee, Jeungsun
    • Journal of Service Research and Studies
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    • v.10 no.4
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    • pp.43-55
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    • 2020
  • Recently, as the importance of experience data increases, there are many attempts to deal with experience data from a data science perspective. In the case of approaching as a collection method of a quantitative survey method that seeks to quantify numerically such as big data, it is difficult to interpret the value of experience in a wide range, and it is relatively expensive and time consuming, and personal information infringement There is a limit to the analysis due to the risk of However, since ethnography, a procedure for collecting experience data based on qualitative research, is mainly carried out in the natural real environment of future customers from the perspective of users, it is possible to confirm the nature that customers face with a small sample. In addition, it is also easy to interpret the relational dimension of the empirical data. Although the ethnography method of collecting experiential data is economical and efficient, it is important to reduce errors in the collection process because the lack of scientific procedures for the data collection process can be a problem. It is important to secure the validity of whether the correct measurement tool is used for ethnography-based experiential data collection and to secure the reliability of the use of a valid measurement tool and method by accurately selecting the measurement target. From this point of view, it is necessary to verify the reliability of the research method that clearly selects the measurement target and secures the validity for the development of the correct measurement method and tool for the collection of ethnography experience data. Therefore, in this study, a verification study was conducted on the data and methodology cases of the'I know you_AI' service that analyzes the customer experience of self-employed based on the ethnography method of collecting experience data..

The Necessary to Make a New Category as 'Women Laborer' : Focused on a Documentary Movie, Weabak ('여성노동자'라는 새로운 범주설정의 필요성 : 다큐멘터리 영화 <외박>을 중심으로)

  • Bae, Sangmi
    • Women's Studies Review
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    • v.31 no.1
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    • pp.93-116
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    • 2014
  • This thesis discussed the status of women workers as wage laborers and home laborers and the valid of a documentary movie for representing women laborers through a documentary movie, Weabak that revolved around Home-ever occupation strike leaded E-Land labor union at 30th June, 2007. Jobs for women labors got covered by the flow of flexibility with the policy of labor flexibility in South Korea during 1990s. The reasons that justify this trend are their position in the households, and their roles in working places are not very important because there are not required difficult skills. The mass dismissal which caused the E-Land strike also shared these ideologies. In Weabak, since women laborers were always expected to care for their family, they were need strikes in their home as well as their working place. However, a household is a basement for them to get the identity as a women laborer. It has two ambivalent meanings, as a protected area and disorder for them to pursue their life at the same time. Identity of Women laborers, domestic laborers as well as wage laborers, are very difficult to identify as a general noun, a laborer. Weabak is an important example to show us the possibility of a documentary as searching new realism for representing women laborers' story using their own perspective.

A Study of Home-visit Care Agencies' Perceptions and Attitudes toward Home and Community Long-term care Agency Quality Assessment (HCLA-QA) Program (방문요양기관의 재가장기요양기관평가에 대한 인식 및 태도)

  • Han, Eun-Jeong;Lee, Jung-Suk;Kwon, Jinhee
    • 한국노년학
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    • v.32 no.2
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    • pp.467-485
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    • 2012
  • National Health Insurance Corporation initiated Home and Community Long-term care Agency Quality Assessment(HCLA-QA) program in 2010. This study aims to explore long-term care agencies' perceptions and attitudes toward HCLA-QA program, focused on the home-visit care agencies. Total 473 agencies completed the questionnaires(response rate 13.6%), using the e-mail and fax survey methods with high-capacity web-fax server of NHIC. On the results of this study, we found the agencies' different perceptions and attitudes on HCLA-QA program according to their quality ratings as QA results. Compared to the agencies with low quality ratings, the agencies with high quality ratings tend to have more time for preparation, better understandings about HCLA-QA program, more positive perceptions that quality indicators generally are valid, and more affirmative attitudes that the notifications of QA results are helpful for agencies. Our findings can be very useful for establishing strategies for improving the HCLA-QA program. The policy makers, the insurer, and the agencies need to consider the opinions of the agencies with high quality ratings as well as the ones with low quality ratings.

A Case Study on Field Campaign-Based Absolute Radiometric Calibration of the CAS500-1 Using Radiometric Tarp (Radiometric Tarp를 이용한 현장관측 기반의 차세대중형위성 1호 절대복사보정 사례 연구)

  • Woojin Jeon;Jong-Min Yeom;Jae-Heon Jung;Kyoung-Wook Jin;Kyung-Soo Han
    • Korean Journal of Remote Sensing
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    • v.39 no.6_1
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    • pp.1273-1281
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    • 2023
  • Absolute radiometric calibration is a crucial process in converting the electromagnetic signals obtained from satellite sensors into physical quantities. It is performed to enhance the accuracy of satellite data, facilitate comparison and integration with other satellite datasets, and address changes in sensor characteristics over time or due to environmental conditions. In this study, field campaigns were conducted to perform vicarious calibration for the multispectral channels of the CAS500-1. Two valid field observations were obtained under clear-sky conditions, and the top-of-atmosphere (TOA) radiance was simulated using the MODerate resolution atmospheric TRANsmission 6 (MODTRAN 6) radiative transfer model. While a linear relationship was observed between the simulated TOA radiance of tarps and CAS500-1 digital numbers(DN), challenges such as a wide field of view and saturation in CAS500-1 imagery suggest the need for future refinement of the calibration coefficients. Nevertheless, this study represents the first attempt at absolute radiometric calibration for CAS500-1. Despite the challenges, it provides valuable insights for future research aiming to determine reliable coefficients for enhanced accuracy in CAS500-1's absolute radiometric calibration.

Accelerator Incubation Program and Entrepreneurial Performance of Portfolios : Focusing on the Moderating Effect of Accelerator Entrepreneur Passion (액셀러레이터 보육프로그램과 보육기업의 창업성과 : 액셀러레이터 창업가 열정의 조절효과 중심으로)

  • Kim, Sang-cheol;Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.5 no.3
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    • pp.1-17
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    • 2022
  • Entrepreneurs recognize that their passion was an important factor in driving successful entrepreneurship. However, they were often unaware of the impact that third-party passions related to startups have on them. Therefore, in this study, it was verified whether the accelerator incubation program had an effective effect on portfolios. At this time, I tried to do an empirical analysis focusing on how the third-party accelerator entrepreneur passion affects the entrepreneurial performance of portfolios. To this end, a survey was conducted on representatives of portfolios across the country who completed the accelerator incubation program, and empirical testing was conducted based on 330 valid ones. As a result of empirical analysis, it was confirmed that mentoring and networking among accelerator incubation programs had a positive (+) effect on entrepreneurial performance of portfolios. On the other hand, education and seed investment in the accelerator program did not significantly affect the entrepreneurial performance of portfolios. On the other hand, it was tested that accelerator entrepreneur passion significantly moderated both the incubation program elements (education, mentoring, network, seed investment) and the entrepreneurial performance of portfolios. The results of this study are meaningful in that they reveal that the passion of accelerator entrepreneurs is an important lynchpin of incubation programs and the key to success in startups. In addition, this study suggests that it is important for startups to go one step further from seed investment and properly identify the accelerator entrepreneur and his passion, the key man of accelerators.

A Validation Study of the Korean Version of the Workplace Intergenerational Climate Scale(K-WICS) (한국판 세대친화적 조직문화척도(K-WICS) 타당화 연구)

  • Seoyeong Jeong;Hee Woong Park;Young Woo Sohn
    • Korean Journal of Culture and Social Issue
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    • v.29 no.4
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    • pp.429-453
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    • 2023
  • Due to recent demographic changes, employees from diverse generations now work together in organizations. Thus, there is a need for research on intergenerational cooperation. However, the lack of valid and reliable measures to capture intergenerational climate in the workplace is an obstacle to research. Therefore, we translated the Workplace Intergenerational Climate Scale(WICS) into Korean and validated it with a sample of 1,052 Korean full-time employees. Firstly, we conducted an exploratory factor analysis by using sample 1(N = 460) and revealed a five-factor solution. Secondly, the confirmatory factor analysis(sample 2; N = 592) showed a good model fit of the correlated five-factor model. Thirdly, the scale's discriminant and convergent validity was supported by negative correlations with four types of existing ageism scales and by positive correlations with trust, organizational commitment, work engagement, psychological safety, intention to remain, job satisfaction, and communication satisfaction. Moreover, it further demonstrated significant incremental validity in predicting positive outcome variables even when controlling for pre-existing agism scales. Lastly, we confirmed strict measurement invariance of the scale between the age groups(below 40 versus above 40). The findings support the reliability and validity of the Korean version of WICS among Korean employees. The scale will be broadly applied to measure intergenerational climate of organizations and provide practical implications for HR management.