• Korean journal of applied entomology
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• v.61 no.4
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• pp.549-554
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• 2022

Life table-related studies in insect ecology have been an interesting topic for insect researchers. Two calculation methods are commonly applied to estimate the intrinsic rate of natural increase (r_m) in the life table statistics. The first method is to estimate an approximate r_m by dividing the natural logarithm of the net reproductive rate (R₀) by mean generation time (T) (namely mean generation time-based method). Another approach is to apply the Lotka-Euler equation derived from the population growth equation of Lotka-Volterra to estimate accurate r_m using the maximum likelihood method (Lotka-Euler equation-based method). In the latter case, there is a difference in the estimated r_m value when the initial age class of the target cohort was set to "0" or "1", which confused the application. In this short review, a brief history of the calculation process of the life table was reviewed. It was again confirmed in the Lotka-Euler equation-based method that the form of $\sum\limits_{x=1}^{w}e^{-rx}l_xm_x=1$ should be applied to estimate r_m when the first age class was set to zero, while the form of $\sum\limits_{x=0}^{w}e^{-r(x+1)}l_xm_x=1$ when set to one.

• Journal of Korean Society of Archives and Records Management
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• v.23 no.3
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• pp.63-87
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• 2023

The study aims to investigate research trends in the UK records management field and compare the results with domestic research by analyzing research articles published in Archives and Records for the UK's research trends and The Korean Journal of Archival Studies (KJAS) for domestic ones. The study analyzed 318 articles published in KJAS and 142 articles published in Archives and Records since 2013, when the journal changed its title from Journal of the Society of Archivists, to investigate the distribution of authors, including the ratio of coauthorship and authors' affiliations. A set of 1,251 unique terms were extracted from KJAS, and 508 unique terms were extracted from Archives and Records for keyword co-occurrence network analyses. The result shows that the main research topics for KJAS include studies on (1) records management in general, such as archives, records, records management, and archival information service, (2) public records management, (3) personal or private records management, and (4) the techniques for records management, such as archival appraisal, selection, and disposition. In Archives and Records, (1) there are several case studies related to community and local archives, and (2) studies related to records management techniques, such as records description, appraisal, access, preservation, and service, have been performed continuously; furthermore, (3) studies on the digitization of oral history and audiovisual records are also one of the most researched areas.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.33 no.1
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• pp.5-24
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• 2022

As a new academic publication model is attempted to improve the transparency, efficiency, and speed of scientific knowledge production and distribution, the open peer review platform for verification and openness of peer review history is also activated. Publons is a global platform for tracking, validating, disclosing, and recognizing the peer-reviewed histories of more than 3 million researchers worldwide. This study analyzed the review activities of 579 researchers from domestic universities who are actively reviewing international journals through Publons. As a result of the analysis, first, researchers from domestic universities who actively review international academic journals were found to be in the fields of medicine and electrical and electronics, and in most fields, assistant professors or higher with high WOS indexed research papers are participating. Second, there was a long-tail phenomenon in which a small number of reviewers with extremely high number of review papers existed in all academic fields, and there was no significant difference in the number of review papers and review report length depending on the nationality, academic status, and age of the reviewers. Lastly, although there was a weak correlation between the amount of papers reviewed by reviewers and the number of published papers, it was found that researchers with an extremely large number of reviews do not necessarily produce as many research papers.

• Korean Journal of Ichthyology
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• v.35 no.1
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• pp.10-19
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• 2023

This study aimed to examine the early life history of Trident goby (Tridentiger brevispinis) by observing their egg development and juvenile fish morphology. The average size of mature eggs was 1.13~1.41 (1.30±0.07) mm (n=30), and 0.70~0.86 (0.79±0.04) mm (n=30) in long diameter and short diameter, respectively. The incubation period at 24±1℃ ranged from 167~228 h. The newly hatched larvae measured 2.31~2.78 (2.51±0.18) mm (n=30) in total length (TL), and their mouth and anus were not yet open. At 3 days after hatching, the preflexion larvae reached 2.84~3.10 (2.98±0.10) mm in TL, where in their yolk absorption was complete and their mouths began to open. At 19 days after hatching, the larvae reached the flexion stage, measuring 4.02~4.62 (4.36±0.19) mm in TL. The tip of their notochord was bent upward. At 30 days post-hatching, the larvae reached the postflexion stage, measuring between 5.04~6.36 (5.76±0.51) mm in TL, with the tip of the caudal fin bent at 45°. After 54 days, the larvae had reached the juvenile stage, measuring between 7.43~9.84 (8.48±0.90) mm in TL, and were differentiated by their constant number of fins (6 first dorsal, 12 second dorsal, 11 anal, and 10 ventral fins). This study found that T. brevispinis had larger fertilized eggs and a greater number of myotomes in hatching larva than similar species. Additionally, the distribution of melanophores in T. brevispinis was distinct from that in other similar species, making it easy to distinguish them morphologically.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.2A
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• pp.93-102
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• 2010

The numerical analysis and safety assessment by construction stages were considered the essential examination particular in order to solving the unstability of long-span bridges in the middle a construction. When estimating structural response characteristics by the construction stage analysis of long-span bridges, the influence of the near-field ground motion (NFGM) would be evaluated as a critical factor for the seismic design because it indicates clearly different aspects from the existing input earthquake motion data. Therefore, this study re-examined the response aspect of long-span bridges considering NFGM characteristics based on the response spectrum result, and advanced the presented numerical analysis program by the related research for conducting the construction stage analysis and reliability assessment of long-span bridges efficiently. The excellency of various construction schemes was assessed using the time history analysis result of critical member considering NFGM characteristics. For evaluating quantitative safety level, the reliability analysis was conducted considering the influence of external uncertainties included in random variables, and presented the safety index and failure probability of the critical construction stage by NFGM characteristics. In addition, the reliability result was examined the influence of internal uncertainties using monte carlo simulation (MCS), and assessed the distribution aspect of the essential analysis result. It is expected that this study will provide the basic information for the construction safety improvement when performing seismic design of long-span bridges considering NFGM characteristics.

• Asia Marketing Journal
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• v.15 no.4
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• pp.1-32
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• 2014

The purpose of this paper is to investigate upon a diversification strategy through market creation of CJ Group, which has contributed in positioning of the firm as one of the leading conglomerates in South Korea. With such objective, the background of CJ Group, followed by its business diversification strategies were explored, with reference to several case studies. The history of CJ Group began with establishment of CheilJedang Industrial Corporation in 1953, as the first domestic sugar producer and exporter of South Korea. The corporation gradually expanded its business ever since at both national and global level, to include the fields of food production, pharmaceutical, biotechnology, and life chemicals. Later, CheilJedang (CJ) Group was established as an affiliate of CheilJedang Industrial Corporation. With such independence, extension of business has been witnessed across the industries of media, entertainment, finance, information technology and distribution. Thus, the current CJ Group pursues to define itself as a progressive global living culture company with four major business categories from food and food service, biotechnology, entertainment and media, and logistics. Despite its success in today's market, CJ Group underwent hardships in its business diversification in 1990s due to indiscreet management, along with the Asian financial crisis. Here, many firms overcame the financial difficulties by taking advantage of the exchange rate for overseas expansion. Though, CJ Group tried to differentiate itself by focusing on the domestic market by creating something out of nothing. Hence, CJ Group takes a unique position among many cases of business diversification and their categorization. In an effort to identify and classify the types of growth experienced by the top 30 companies in South Korea, the firms were categorized into four groups according to their diversification strategies adapted after the Asian financial crisis. Based on the mode and time of entry, corporations were identified either as the 'Explorer', 'Invader', 'Venture Capitalist', or 'Assimilator'. Here, the majority of the firms showed the qualities of Invader, entering mature markets through large-scaled mergers and acquisitions. However, CJ Group was the only firm that was categorized as an Explorer, for its focus on the newly emerging service sector in culture-contents industry. This diversification strategy through market creation is worth examining, due to its contribution in generating simultaneous growth between the market and the company itself. Diverse brands of CJ Group have been referred to as case studies in this regard, from 'Hatban', 'Cine de Chef', 'VIPS' to 'CJ GLS'. These four businesses, each to represent processed food, film, restaurant service, and logistics industries respectively, show CJ Group's effectiveness in creating a whole new category of goods and services that are innovative. In fact, such businesses not only contributed in advancement of consumers' wellbeing, but toward generating additional value and employment. It is true that the diversification strategy of CJ Group requires long-term capital investment with high risk, compared to the other strategies mentioned in the paper. However, this model does create high employment and additional values that are positive to both the society and the firm itself. Therefore, the paper comes to a conclusion that the diversification strategy through market creation conveys the most positive impact relative to the others.

• Korean Journal of Acupuncture
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• v.40 no.4
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• pp.184-193
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• 2023

Objectives : The purpose of this study is to understand the temperature characteristics depending on the thickness and material of the needle used with the Electronic Warm Acupuncture Device (EWAD). Methods : We controlled experimental environment and measured temperature changes of a silicon phantom in which K-type thermocouples were inserted at depths of 2, 7 mm. EWAD perfomed with acupuncture needles of various thicknesses (0.25×60 mm, 0.40×60 mm, and 0.50×60 mm) and materials (Gold 0.40×50 mm). We set non-needle (only heated with EWAD skin heater) group as a control group. Results : The maximum temperature and temperature changes of 0.40 mm, 0.50 mm needle group were significantly higher than the non-needle group. The highest temperature range in all needle groups was 0.50 mm needle group (41.44±0.31℃). However, the 0.25 mm needle group was not significantly different from the non-needle group. Maximum temperature of gold needle group was significantly higher than stainless steel needle group. Temperature changes of gold needle group were higher than stainless steel group at the depth of 7 mm. Conclusions : It was found that needle thickness and material of acupuncture had an effect on the temperature of the EWAD. When performing EWAD treatment, consideration of thickness and material of acupuncture is needed. Future research is needed using phantoms that can reflect actual clinical situations and better mimic the human body.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.469-489
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• 2023

Six field surveys were conducted at 29 locations from April 2020 to April 2022 to identify the freshwater flora of the Taean Peninsula. Based on the collected specimens, the vascular plants of the Taean Peninsula were summarized as 391 taxa: 94 families, 248 genera, 362 species, 5 subspecies, and 24 varieties. Freshwater plants in the Taean Peninsula consisted of 104 taxa, 45 taxa for aquatic plants, and 59 taxa for wetland plants. When classified by life history, annuals accounted for 33 taxa, winter annuals 5 taxa, biennial 6 taxa, and perennials accounted for most of the 60 taxa. Among the 391 identified taxa, 2 taxa of Endangered plants, 3 taxa of Korean endemic plants, 5 taxa of IUCN red list plants, 49 taxa of Korean floristic target plants, 38 taxa of biological resources subject to the approval of outbound transfer, 55 taxa alien plants and 7 taxa of ecosystem disturbing plant. The results of this study are intended to be used as basic data on the freshwater environment and distribution of aquatic plants in the Taean Peninsula.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.14 no.2
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• pp.90-101
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• 2009

Analysis of multi-channel seismic reflection data from the Southern Ulleung Basin reveals that Plio-Quaternary section in the area consists of nine stacked sedimentary units separated by erosional unconformities. On the southern slope, these sedimentary units are acoustically characterized by chaotic seismic facies without distinct internal reflections, interpreted as debris-flow bodies. Toward the basin floor, the sedimentary units are defined by well-stratified facies with good continuity and strong amplitude, interpreted as turbidite/hemipelagic sediments. The seismic facies distribution suggests that deposition of Plio-Quaternary section in the area was controlled mainly by tectonic movement and sea-level fluctuations. During the Pliocene, sedimentation was mainly controlled by tectonic movements related to the back-arc closure of the East Sea. The back-arc closure that began in the Miocene caused compressional deformation along the southern margin of the Ulleung Basin, resulting in regional uplift which continued until the Pliocene. Large amounts of sediments, eroded from the uplifted crustal blocks, were supplied to the basin, depositing Unit 1 which consists of debris-flow deposits. During the Quaternary, sea-level fluctuations resulted in stacked sedimentary units (2-9) consisting of debris-flow deposits, formed during sea-level fall and lowstands, and thin hemipelagic/turbidite sediments, deposited during sea-level rise and highstands.

• Journal of The Korean Association For Science Education
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• v.27 no.5
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• pp.379-393
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• 2007

The purpose of this article is to analyze the conceptual change of nine 11th graders after implementing the model-based instruction of blood circulation by multidimensional framework, and to find some implications about teaching strategies for improving conceptual understanding. The model-based instruction consisted of 4 periods: (1) introduction for inducing students' interests using an episode in the science history of blood circulation, (2) vivisectional experiment on rats, (3) visual-linguistic model instruction using the videotape of heartbeat, and (4) modeling activity on the path of blood flow. Based on the data from pre-test, post-test and interviews, we classified students' models on the path of blood flow, and investigated their ontological features and the conceptual status of blood circulation. Most students could describe the path of blood flow and the changes of substances in blood precisely after the instructions. However, the modeling activity were not sufficient to improve students' understanding of the mechanisms of the blood distribution throughout various organs and the material exchanges between blood and tissues. From the interview of 9 students, we acquired informative results about conceptual status elements that were helpful to, preventing from, or not used for students' understanding. It was also found that conceptual status of students depended on the ontological categories into which students' conceptions of blood circulation fell. The results of this study can help design the effective teaching strategy for the understanding of concept of the equilibrium category.