• 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.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.281-290
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• 2020

Given the rise in international tourism and the rapid growth of the Vietnamese economy, the hospitality industry in Ho Chi Minh City, Vietnam's commercial hub, has been facing severe labor shortages due to competition with other fast-growing parts of the economy. These struggles to acquire high-quality employees is strangling future growth and placing new importance on the role of recruitment. To better understand the effectiveness of an organization's recruitment strategy, recruiters need to ascertain the Job Pursuit Intention (JPI) of job seekers to efficiently align an applicant's work notions with the organization's goals. This study aims to investigate the factors impacting on JPI among employees working in the hotel sector in Ho Chi Minh City. Secondary data are from previous studies and primary data are from consultation with 10 experts, group discussions and five in-depths structured interviews with 15 random employees and 302 survey questionnaires with employees working in three five-star hotels. Cronbach's Alpha, EFA, T-Test, ANOVA are used for statistical analysis. The findings show that compensation, career advancement, and work-life balance affect JPI of job seekers, in which compensation is the most influential factor. Furthermore, recommendations for recruiters, further research and limitations of this study have been laid out.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.261-278
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• 1998

The paper represented the lower extremity muscle model as four rigid-body segments: trunk, shank, and foot. We transformed their tibial data into our shank data by rotating their tibial X and Y axes by 5.483 degrees, so the revised coordinate data used to translating the origin of their tibial reference frame to our shank reference frame. According to weight of subject, physiological cross-setional area(PCSA) of each lower extremity muscle was calculated by scaling those data by Brand. The objectives of this paper are to investigate the variations of the recruitment patterns of the lower extremity muscles, and to analyze the changes of the role assigned to each muscle during the seated foot operation. For exertion levels, the transition point of type F motor unit of each muscle is inferred by analyzing the electromyogram at the seated postures. Also, for predetermined seated foot operations exertion levels, the recruitment pattern and the changes of the role assigned are identified in the continuous exertion, by analyzing the electromyogram changes due to the accumulated muscle fatigue. This study can be used to design and to assess the pedals and foot-related equipments design.

• Journal of the Korean Society for information Management
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• v.24 no.1 s.63
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• pp.147-164
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• 2007

This study proposes additional service pages for users, researchers, institutions to activate academic institutional repository which captures, disseminates, and manages various academic resources, i.e. theses, dissertations, journal articles, research reports, and so on. The research methods include literature study, case study, and site analysis on the current homepages of Ewha Womans University faculties & institutions. As a result, components and functions of additional service pages such as researchers' pages are suggested. Additional service pages will be made it possible for researchers to submit their products willingly and for academic institutional repositories to activate their services and improve content recruitment in the end.

• Restorative Dentistry and Endodontics
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• v.25 no.2
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• pp.212-218
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• 2000

The recruitment of leukocytes to a site of inflammation is dependent on a complex interplay of a number of cytokines. Monocyte chemoattractant protein-1 (MCP-1) is a potent chemoattractant for monocytes, whereas interleukin-8 (IL-8) has chemotactic activity for neutrophils, lymphocytes, and basophils. The purpose of this study was to determine the effects of several microbes found in infected root canal systems on the production of inflammatoy cytokines, interleukin 8 and monocyte chemoattractant protein-1 from human peripheral blood mononuclear cells (PBMC). Monocytes isolated from peripheral blood were stimulated by group A streptococci (GAS, ATCC 19615), Enterococcus faecalis (ATCC 29212), Streptococcus mutans (ATCC 10449), Streptococcus sanguis (clinical isolate), and Candida albicans (ATCC 90029) respectively. Each of these bacteria induced dose-dependent induction in IL-8 and MCP-1 determined by ELISA. IL-8 production by each bacteria was decreased in the range of the microbe-to-PBMC ratios of 0.1-1.0. Group A streptococci was the week inducer of MCP-1 production. These results suggest that different oral pathogens induce specific dose-dependent patterns of cytokine release. Such patterns may provide a means of control of the type of immune celles particularly with regard to inflammatory leukocyte recruitment.

• Physical Therapy Korea
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• v.9 no.3
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• pp.125-135
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• 2002

In most of the medical literature that discusses the common problem of movement in patients with cerebral lesions. This critical problem is ascribed to a mechanism involving uninhibited neural activity. The goals of neurological physical therapy are focus on reduce of muscle hypertonicity, facilitates muscle activities, and improve of performance in living environment. A variety of studies suggest that spasticity is a distinct problem and separate from the muscle weakness. It has become increasingly recognized that the major functional deficits following brain damage are largely due to negative features such as muscle weakness and loss of performance rather than spasticity. Adequate recruitment of prime mover, not release was able to carry out the movement tasks well. The strengthening exercise of spastic limbs on changes in muscle properties and performance skill, the repeated motor practice has been identified as crucial for motor recovery. This article support the concept that strengthening is an appropriate intervention to improve the quality of physical function in patients with central nervous system lesions. Further studies and therapeutic approaches should be efforts at improving motor neuron recruitment in agonist rather than reducing activity in antagonists while retraining muscle strengthening.

• Journal of Korea Technology Innovation Society
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• v.19 no.2
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• pp.395-415
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• 2016

As international mobility of the high-caliber manpower increases, recruitment of the brain from overseas becomes a critical factor in determining national innovation capacity. This paper reviewed the theories of reverse brain drain, summarized the factors for recruitment of the brain from abroad, and empirically analyzed priority of the factors through the survey on overseas scientists from Vietnam, using conjoint analysis. The results of the analysis shows that high-level salaries, proper research environments, and environment for child education were the important factors. Factors such as scientists respect culture and career development opportunities are not considered important. This paper shows that the exceptionally higher salary should be paid and it also indicates that the policy determination from Vietnam government should be made accordingly.

• Research in Community and Public Health Nursing
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• v.30 no.4
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• pp.391-399
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• 2019

Purpose: Recent advances in computer and mobile technologies have brought increasing usages of IT technology in nursing research across nursing fields. Despite the increasing usages, there has been little discussion on methodological issues involved in nursing research using IT technology. This is a discussion paper to identify methodological issues in IT technology-based nursing research. Methods: An analysis was done using content analysis on research team meeting minutes and research team members' research diaries in a clinical trial that tested the efficacy of a technology-based intervention. First, several major categories of IT technology-based nursing research are concisely summarized. Then, the method that was used for this analysis is presented. Results: The findings are presented as themes reflecting methodological issues in IT technology-based research: (a) difficulties in recruitment due to necessary technology literacy; (b) facilitating recruitment through allowing the use of multiple languages; (c) participants' preferences for specific IT technology; (d) efforts needed to ensure technological security; (e) participants' preferences for design; and (f) necessary considerations on timing. Conclusion: Finally, future directions for nursing research using IT technology are proposed based on the identified issues.

• Journal of Information Technology Services
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• v.20 no.4
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• pp.35-52
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• 2021

Nowadays data-based decision making is emerging as the center of the business environment paradigm, but many companies do not have data-driven decision-making systems. It has also been studied that using an expert's intuition in decision making can be more efficient in terms of speed and cost, compared to analytical decision making. The goal of this study is to analyze customer churn factors using a group of experts within a financial company from the viewpoint of decision-making efficiency. We applied a debit card 'A', product of the National Credit Union Federation of Korea. The churn factors of all the financial expert groups were examined. Also. the difference in each group (management support, card recruitment, customer service group) was analyzed. We expect that this study will be helpful in the practical aspects of managers whose environments is lack data-oriented infrastructure and culture.

• 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.