• The Mathematical Education
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• v.60 no.1
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• pp.111-131
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• 2021

This study aims to investigate how secondary mathematics teachers understand and intend to use textbooks for their mathematics instruction. For this purpose, we developed a set of survey items in order to unpack what the teachers understand the mathematical tasks suggested in the textbooks in terms of the levels of cognitive demand and how they intended to use the tasks in the textbooks for their teaching. Twenty-five teachers participated in the survey. The data from the survey were analyzed. The findings from the data analysis suggested as follows: a) the teachers seemed to closely follow textbooks without attempting to modify the tasks, even when the teachers consider it is necessary to modify textbook tasks to high-level tasks, b) the teachers seemed to be unstable in regards that they admitted themselves very competent for modifying tasks for developing students' mathematical thinking but, at the same time, they were uncomfortable with transforming tasks into cognitively demanding tasks that promote students' mathematical understanding, and c) the teachers appeared to consider textbooks as significant criteria in conducting tests including midterm and final exam. In conclusion, the teachers seemed to intend to follow closely the contents and sequence of mathematics textbooks in their mathematics classrooms.

• Journal of Information Technology Services
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• v.21 no.4
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• pp.27-61
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• 2022

In order to improve project performance by analyzing the effects of the project manager's leadership competency and the individual competency of the project participants on the project performance, this study examines the effect. In this study, a research model and hypothesis were established to understand the causal relationship between leadership competency, individual competency, and project performance, and a survey was conducted based on this. Overall, it was found that the leadership competency of the project manager and the individual competency of the project participants had a positive effect on the project management performance, the project leadership competency had a positive effect on the completion performance, and the project participant individual competency had a negative effect on the completion performance. As a result of analyzing the effect of the project manager's core competency on the project management performance according to the amount or period of the project type, which is the moderating variable, it was found that there was no moderating effect on the management performance. For the success of the SI project, it is most important to understand the project characteristics well and select a PM suitable for the characteristics, and methods for nurturing excellent project managers should be further studied. In addition, it is expected that it will be possible to identify the effect of project manager leadership competency and participant competency on project performance based on sophisticated research design for more competent PM selection.

• Clinical and Experimental Reproductive Medicine
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• v.49 no.3
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• pp.175-184
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• 2022

Objective: The aim of this study was to evaluate the impacts of platelet-rich plasma (PRP) and conditioned medium (CM) derived from endometrial stromal cells on mouse preantral follicle culture in a two-dimensional system to produce competent mature oocytes for fertilization. Methods: In total, 240 preantral follicles were isolated from female mouse ovarian tissue and divided into four groups. The preantral follicles were isolated three times for each group and then cultured, respectively, in the presence of alpha minimum essential medium (control), PRP, CM, and PRP+CM. The in vitro growth, in vitro maturation, and cleavage percentage of the preantral follicles were investigated. Immunocytochemistry (IHC) was also conducted to monitor the meiotic progression of the oocytes. Additionally, the mRNA expression levels of the two folliculogenesis-related genes (Gdf9 and Bmp15) and two apoptosis-related genes (Bcl2 and Bax) were investigated using real-time polymerase chain reaction. Results: In the PRP, CM, and PRP+CM groups, the preantral follicle maturation (evaluated by identifying polar bodies) were greater than the control group. The cleavage rate in the CM, and PRP+CM groups were also greater than the control group. IHC analysis demonstrated that in each treatment group, meiotic spindle was normal. In the PRP+CM group, the gene expression levels of Bmp15, Gdf9, and Bcl2 were greater than in the other groups. The Bax gene was more strongly expressed in the PRP and control groups than in the other groups. Conclusion: Overall, the present study suggests that the combination of CM and PRP can effectively increase the growth and cleavage rate of mouse preantral follicles in vitro.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.405-413
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• 2021

The purpose of this study was conducted to identify perceptions about the relationship between poverty and health and examined the attitudes toward poverty among nursing students. This study administered a standardized questionnaire to 198 nursing students at a university. The data were analyzed using SPSS 22.0. The results of the study showed that nursing students recognized the importance of nursing education for poverty. They also recognized that clinical practice and extra-curricular programs such as volunteer activities were necessary for nursing education. Furthermore, they were aware of the vicious cycle of poverty and health; however, their awareness of the health behavior of the poor was insufficient. In the perception of attitudes toward poverty, individual explanations of poverty tended to be more common than structural explanations, and there was a difference in scores according to age, economic level, political orientation, and clinical practice. In conclusion, it is necessary to develop programs, such as multidisciplinary convergence clinical practice education and volunteer activities, to produce competent nurses to health inequity care for the poor.

• Journal of Korea Trade
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• v.23 no.7
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• pp.96-112
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• 2019

Purpose - "Trade Facilitation" aims the easier flow of trade across borders, driven not only by effective customs administration, the efficiency of appropriate authorities, but also by telecommunications, the quality of infrastructures and competent logistics. Facilitating trade will help lower trade development costs as well as improve economic development and enhance economic benefits for emerging economies at a time when imports and exports are sent in and out across borders several times in the form of intermediate and final products. Not only that, globalization is being accelerated, which in turn increases competitiveness and this makes logistics one of the key factors when it comes to international trade. Highly efficient logistics services promote product movement, ensure product safety and delivery speed, and reduce trade costs between countries. The purpose of this study is, by using the LPI indices based on gravity model estimates, to analyze the impact of each LPI component on trade with the 20 biggest exporting countries of Northeast Asian countries-Korea, Japan, and China-which account for 19.05% of global exports. Design/methodology - Also, this study statistically analyzes the impact of trade on Northeast Asian countries' top 20 exporting countries, using the LPI indices relevant to Trade Facilitation based on the gravity model estimates. Findings - As a result, it was turned out that the distance, GDP, and the LPI components have relevant impact on the trade exports of all three countries but demonstrated little relation to the demographic perspective. Originality/value - The study also found we can increase the trade volume by improving three countries' trade partners' LPI indices since Korea, Japan, and China share most of their 20 biggest trade partners.

• Development and Reproduction
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• v.24 no.4
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• pp.249-261
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• 2020

Spermatogonial stem cells (SSCs) have stemness characteristics, including germ cell-specific imprints that allow them to form gametes. Spermatogenesis involves changes in gene expression such as a transition from expression of somatic to germ cell-specific genes, global repression of gene expression, meiotic sex chromosome inactivation, highly condensed packing of the nucleus with protamines, and morphogenesis. These step-by-step processes finally generate spermatozoa that are fertilization competent. Dynamic epigenetic modifications also confer totipotency to germ cells after fertilization. Primordial germ cells (PGCs) in embryos do not enter meiosis, remain in the proliferative stage, and are referred to as gonocytes, before entering quiescence. Gonocytes develop into SSCs at about 6 days after birth in rodents. Although chromatin structural modification by Polycomb is essential for gene silencing in mammals, and epigenetic changes are critical in spermatogenesis, a comprehensive understanding of transcriptional regulation is lacking. Recently, we evaluated the expression profiles of Yin Yang 1 (YY1) and CP2c in the gonads of E14.5 and 12-week-old mice. YY1 localizes at the nucleus and/or cytoplasm at specific stages of spermatogenesis, possibly by interaction with CP2c and YY1-interacting transcription factor. In the present article, we discuss the possible roles of YY1 and CP2c in spermatogenesis and stemness based on our results and a review of the relevant literature.

• Journal of the Economic Geographical Society of Korea
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• v.24 no.2
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• pp.163-180
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• 2021

Nuclear power has been an attractive energy efficient and to the pressure with the climate change despite of its risks. There are safety, security, and environmental concerns with the nuclear radiation, but the techno-optimism forms the mainstream by experts and the state to be able to control and manage the risks yet occurred. The disastrous Chernobyl and Fukushima nuclear accidents brought about alternative action and thought including renewable energy expansion, efficient energy delivery and use, and enhancing stewardship to environmental carrying capacity. More significant alternative movement is sought by victims of nuclear radiation, technicians, and the general public who realized the pitfalls of expert and state centered policy formation. These laypersons become counter-expertise competent in recognizing local contamination and considering the risks and emotions seriously affecting peoples' everyday lives. They play important roles in the construction and legitimation of alternative knowledge about nuclear power widely realized across regions.

• Journal of Biomedical Engineering Research
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• v.44 no.1
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• pp.1-10
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• 2023

With the announcement of MEDICAL DEVICE REGULATION 2017/745 (MDR) on April 5 2017, medical device manufacturers shall apply ISO 14971:2019 (3^rd) revised in December 2019. However, there is not much related information and guidance available to medical device manufacturers, especially single use medical device. Risk management process basically follow 5 steps which are Risk Analysis, Risk Evaluation, Risk Control, Evaluation of overall residual risk and post-production activities. The purpose of this study is to provide a guidance of from risk analysis with Failure Mode and Effects Analysis (FMEA) table to overall residual risk evaluation for the single use medical device and to reflect it in a Periodic Safety Update Reports (PSUR) to satisfy with MDR requirements with single use medical device which are widely used and manufactured FDA class 2 or CE class IIb as examples. For this study, single use medical device manufacturer can adopt ISO 14971:2019 in accordance with MDR requirements and it can be extended to the PSUR. But there are still limitations to adopt to the all-single use medical device especially high class, private device and implantable device. So, Competent Authority (CA) shall publish more guidance for the single use medical device.

• Journal of the Korean Society of Safety
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• v.37 no.1
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• pp.70-77
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• 2022

The total number of Korean restaurants using delivery applications has substantially increased from 7.6% in 2018 to 11.2% in 2019. In 2020, the gross sales in the food delivery service market reached approximately 17 trillion won; this amount is virtually six times that in 2017 (i.e., 2 trillion won). Meanwhile, the annual average death toll of motorcycle riders increased by 3.5%, whereas the number of deaths due to other traffic accidents decreased by 8.2%. Consequently, the foregoing has become a critical social problem. Despite the continuing increase in the number of delivery riders due to the rapid expansion of the delivery industry, no appropriate safety management system has been established. Moreover, the government is experiencing difficulties in assessing the exact situation because of the absence of competent authority. In this study, fundamental data on the characteristics of delivery work and motorcycle accidents were collected through surveys and interviews; then, the influencing factors of traffic accidents were analyzed. Different influencing factors were identified: work experience as a rider; number of deliveries; whether to accept delivery requests in transit; manner of accepting delivery requests; and traffic law violations, such as speeding (for faster delivery) and running a red light. Because the motorcycle delivery industry has a relatively low job-entry barrier (i.e., special qualifications are not required), the riding skills of riders must be improved, and delivery companies must be technically developed to achieve a safe working environment. The results of this study can be utilized as fundamental data for system development or structural improvement of the delivery industry.

• Journal of the Korean Orthopaedic Association
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• v.55 no.5
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• pp.436-443
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• 2020

The main treatment of infections following the repair of a ruptured Achilles tendon is debridement of the infected tissue and reconstruction of the Achilles tendon after controlling the infection. On the other hand, some studies recently reported excellent clinical results after the debridement of the infected Achilles tendon without a reconstruction of the tendon. This paper reports four cases of a competent result after the debridement of an infected Achilles tendon without reconstructing the tendon with a review of the relevant literature.