• Journal for History of Mathematics
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• v.27 no.3
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• pp.197-210
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• 2014

Species like insects and fishes have, in many cases, non-overlapping time intervals of one generation and their descendant one. So the population dynamics of such species can be formulated as discrete models. In this paper various discrete population models are introduced in chronological order. The author's investigation starts with the Malthusian model suggested in 1798, and continues through Verhulst model(the discrete logistic model), Ricker model, the Beverton-Holt stock-recruitment model, Shep-herd model, Hassell model and Sigmoid type Beverton-Holt model. We discuss the mathematical and practical significance of each model and analyze its properties. Also the stability properties of stationary solutions of the models are studied analytically and illustratively using GSP, a computer software. The visual outputs generated by GSP are compared with the analytical stability results.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.345-351
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• 2018

This study was conducted to explain the capacity building policy of local public officials. Especially, it is to derive the policy task that can increase the efficiency within the limit of limited resources. The results of the study are as follows. First, local government officials' job management was the most important policy task in the largest framework to strengthen the capacity of local public officials. Next, the evaluation was in the order of recruitment management of local public officials and personnel management of local public officials. Second, the results of the evaluation of detailed policies. Among the local government officials 'job management, the introduction of the local government officials' rest period was evaluated as the most important. Regarding recruitment management of local public officials, reform of the public official exam courses was evaluated as the most important. In the personnel management of the local public officials, the job training of the elected officials was the most important. The results of this study will help to explain the policy development for strengthening the capacity of local public officials in realistic aspect. In order to strengthen the capacity of local public servants in future, it is necessary to analyze the measurement variables more.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.3
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• pp.262-271
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• 2022

The purpose of this study is to investigate the status of admission and employment in fisheries high schools (FHS) and to consider ways to revitalize FHS through substantialization. The recruitment rate of new students in FHS decreased from 97.4% in 2016 to 83.2% in 2020. The aging training ship that FHS needs to improve most urgently is being jointly used by FHS across the country, and the construction of a joint training ship managed by the Korea Institute of Maritime and Fisheries Technology is being promoted. The average employment rate for FHS by year was 40.2-59.4%, and the fisheries-related employment rate was low at 31.0-38.9%. On the other hand, the acquisition rate of certificate of competence was 37.5-52.0%, and the rate of employment on board of those who obtained the certificate of competence was 42.9-59.8%. In order to secure new students and improve the recruitment rate, we operate experiential classrooms that reflect the characteristics of training ships and departments and conduct public relations activities using sns, publicity video ucc, YouTube, etc. It will be necessary to expand opportunities for fisheries-related vocational experience through active career exploration and elective courses in the FHS credit system. Finally, it is judged that fisheries related government agencies, industries and local governments need to improve their awareness of FHS and plan to support fisheries manpower nurturing in order to attempt the vitalization of FHS.

• Journal of Korea Water Resources Association
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• v.44 no.10
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• pp.797-807
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• 2011

Phenomenon of vegetation recruitment on the sand bar is drastically rising in the streams and rivers in Korea. In the 1960s prior to industrialization and urbanization, most of the streams were consisted of sands and gravels, what we call, 'White River'. Owing to dam construction, stream maintenance, etc. carried out since the '70s, the characteristic of flow duration and sediment transport have been disturbed resulting in the abundance of vegetation in the waterfront, that is, 'Green River' is under progress. This study purposed to identify the correlation among water level, water temperature, rainfall, soil moisture and soil texture out of the factors which give an effect on the vegetation recruitment on the sand bar of unregulated stream. To this purpose, this study selected the downstream of Naeseong Stream, one of sand rivers in Korea, as the river section for test and conducted the monitoring and analysis for 289 days. In addition, this study analyzed the aerial photos taken from 1970 to 2009 in order to identify the aged change in vegetation from the past to the present. The range of the tested river section was 361 m in transverse length and about 2 km in longitudinal length. According to the survey analysis, the tested river section in Naeseong Stream was a gaining river showing the higher underground-water level by 20~30 m compared to Stream water level. The difference in the underground water temperature was less than $5^{\circ}C$ by day and season and the Stream temperature did not fall to $10^{\circ}C$ and less from May when the vegetation germination begins in earnest. The impact factor on soil moisture was the underground water level in the lower layer and the rainfall in the upper layer and it was found that all the upper and lower layer were influenced by soil particle size. The soil from surface to 1 m-underground out of 6 soil moisture-measured points was sand with the $D_{50}$ size of 0.07~1.37 mm and it's assumed that the capillary height possible in the particle size would reach around 14~43 cm. On the other hand, according to the result of space analysis on the tested river section of unregulated stream for 40 years, it was found that the artificial disturbance and drought promoted the vegetation recruitment and the flooding resulted in the frequency extinction of vegetation communities. Even though the small and large scales of recruitment and extinction in vegetation have been repeated since 1970, the present vegetation area increased clearly compared to the past. It's found that the vegetation area is gradually increasing over time.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.133-144
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• 2019

The purpose of this study is to analyze the difference in perceptions of job applicants on core competency in the recruitment environment based on National Competence Standards(NCS), and also to obtain information relating to the seeking of employment and employment education plans. A survey and paired t-test were conducted on 355 job applicants of vocational colleges and four-year universities. Through these applicants, the difference between the current level and level of importance dependent on areas of core competency was analyzed. In addition, IPA analysis was conducted in order to confirm the educational necessity in this area. As a result, there were significant differences between the current level and level of importance in all 10 areas. IPA analysis confirmed that educational needs are prioritized. As a result, it was found that the areas which should be strengthened in both groups were interpersonal ability, communication ability, numerical ability, problem solving ability, and self-development ability. The area recognized as being in 'a state of excess' was resource management ability. As a result of checking the necessity levels of the two groups, it was found that job applicants of vocational colleges had to strengthen their problem solving ability, and the applicants of four-year universities had to intensify their communication ability, interpersonal ability, and information ability.

• Journal of Gastric Cancer
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• v.14 no.1
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• pp.39-46
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• 2014

Purpose: According to current guidelines, perioperative chemotherapy is an integral part of the treatment strategy for advanced gastric cancer. Randomized controlled studies have been conducted in order to determine whether perioperative chemotherapy leads to improved R0 resection rates, fewer recurrences, and prolonged survival. The aim of our project was to critically appraise three major studies to establish whether perioperative chemotherapy for advanced, potentially resectable gastric cancer can be recommended on the basis of their findings. Materials and Methods: We analyzed the validity of the three most important studies (MAGIC, ACCORD, and EORTC) using a standardized questionnaire. Each study was evaluated for the study design, patient selection, randomization, changes in protocol, participating clinics, preoperative staging, chemotherapy, homogeneity of subjects, surgical quality, analysis of the results, and recruitment period. Results: All three studies had serious shortcomings with respect to patient selection, homogeneity of subjects, changes in protocol, surgical quality, and analysis of the results. The protocols of the MAGIC and ACCORD-studies were changed during the study period because of insufficient recruitment, such that carcinomas of the lower esophagus and the stomach were examined collectively. In neither the MAGIC study nor the ACCORD study did patients undergo adequate lymphadenectomy, and only about half of the patients in the chemotherapy group could undergo the treatment specified in the protocol. The EORTC study had insufficient statistical power. Conclusions: We concluded that none of the three studies was sufficiently robust to justify an unrestrained recommendation for perioperative chemotherapy in cases of advanced gastric cancer.

• Journal of Industrial Convergence
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• v.15 no.2
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• pp.45-56
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• 2017

The purpose of this study is to analyze the influence of the number of investors influencing the achievement rate of domestic securities type crowdfunding, to find out why the general investors need to participate and to suggest measures to increase the participation of general investors. The results of this study are as follows. First, the effect of the recruitment amount, the target amount, the recruitment period and the business training is confirmed as factors affecting the achievement rate of domestic securities type crowdfunding. And it was confirmed that the influence factors on achievement rate could have a greater effect as the number of general investors increased. Therefore, the government should make more effort to relax regulations on general investors, and the investor of capital should strengthen the public disclosure of KSM through the KSM market in order to recover the funds of general investors, Crowd funding will be able to attract enough funds.

• Journal of the Korea Society of Computer and Information
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• v.26 no.6
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• pp.167-172
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• 2021

The objective of this study is to present the academic implications and developmental direction of the police assigned for special guard system through big data analysis on the objective and macroscopic viewpoint of the media. As research method, this study conducted the analysis on 'police assigned for special guard' and the analysis of related words that would visualize the keywords highly related to keyword trend and news. Also, after dividing the period into the 1990s, 2000s, and 2010s, the number of relevant articles in each period was drawn for understanding the flow. In the results of this study, the perception of media report of police assigned for special guard was about the recruitment of police assigned for special guard, and relevant events/accidents, which showed the coexistence of positive interest in the recruitment of police assigned for special guard and negative image of events/accidents related to police assigned for special guard. As a result, however, the necessity and demand for police assigned for special guard are increasing. Thus, the police assigned for special guard should be engaged in work after carefully thinking of its role in charge of ethical responsibility and safety as an axis for maintaining the national safety and social order.

• Physical Therapy Korea
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• v.9 no.2
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• pp.33-42
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• 2002

The purpose of this study was to compare the onset times of muscle activities and the order of muscle firing in hamstring gluteus maximus, and lumbar erector spinae muscle during active hip extension between subjects with low back pain (LBP) and healthy subjects. Thirty subjects, 15 with LBP and 15 healthy subjects, participated in this study. Electromyographic activity was recorded during active hip extension in prone and standing position. Relative onset times of these muscle activities were determined. Similar muscle firing order in hamstring, gluteus maximus, and lumbar erector spinae muscle showed in both groups and positions. However, the onset time of gluteus maximus was significantly later in prone and standing active hip extension in subjects with LBP than in healthy subjects. The onset time of lumber erector spinae muscle activity was significantly delayed in subjects with LBP in standing active hip extension, The delayed onset times of gluteus maximus and lumbar erector spinae muscles' activities were probably related to LBP. Further studies are needed to identify whether the delayed onset times of gluteus maximus and lumbar erector spinae muscle activities are the contributing factors to LBP.

• Journal of Navigation and Port Research
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• v.36 no.4
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• pp.291-298
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• 2012

Working onboard large ocean-going vessels is one of many industries that is by its very nature extremely error-provoking. In industries such as aviation, nuclear power, healthcare and transport, the need for mental preparedness and professionalism are amongst the qualities essential for the management of complex hazardous systems. Recruiting, training, and more importantly retaining the right people to work in these industries is of paramount importance if safety is to be continuously improved and economic benefits realized. Through consideration of extant empirical literature this paper will explore the need for enhancing collaboration between shipping companies and maritime training insitutes in order to provide the industry with those most capable for the job. It will be concluded that by providing a strong maritime foundation from the outset of training, maritime academies in South Korea can provide shipping companies with a wealth of highly qualified, motivated officers who will contribute to safety and remain valuable assets within the industry for years to come.