• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.440-449
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• 2015

Pine wood nematode (PWN), Bursaphelenchus xylophilus is one of the most serious pests of pine tree. Trunk injection of some nematicides in tree is well known as an effective control method. However there are some limitating factors which hindering the efficacy of trunk injection in field or potted tree. In this study we suggested easy and useful alternative screening methods of nematicides against PWN. Reproduction of PWN was influenced by tree twig moisture (high reproduction in high moisture trig) and paraffin coating was 78.6% reduced moisture loss in tested twig. There were no reproduction different in up and down site from infection site of twig at 1 month after inoculation of PWN and also distance (5 and 10 cm) from inoculation site of PWN did not influence the reproduction of PWN. Numbers of reproduced PWN were higher with decreasing diameter of twig. Numbers of reproduced PWN were similar to P. thunbergii and P. densiflora. However reproduction was increased depending on high inoculation density and longer propagation period. When inoculation of PWN on cut twig injected with emamectin benzoate 2.15% EC and morantel tartrate 8% SL in trunk of Pinus thunbergii in the field, PWN number were significantly reduced than untreated control. We suggest this screening method for PWN control agents.

• Korean journal of communication and information
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• v.60
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• pp.52-74
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• 2012

Legislation needs to be understood within a political, societal relationship among lawmaking bodies rather than by legal provision itself. In order to examine features and functions of communication in the process of legislation, this study conducted focus group interviews with experts as well as in-depth individual interviews. The result of this research as follows: First, the study found that although the domestic legislative process has been made by active interactions among lawmaking subjects, it was hard to conclude that this procedure is providing effective and productive legislative agenda because of chaotic communications made along the process. Second, the study found that national legislative process has been gradually moving, although restricted, to an open political space, the National Assembly, from a closed space, the executive branch. Third, the study found a remarkable feature including growing influence of experts groups and civic organizations in the legislative process. It is a significant change that legislative staff such as National Assembly aides, investigators, expert committeemen and deputy director generals played a role of "insiders," unnoticeably influencing the legislative process, and that civic organizations and NGOs, which have been excluded in the previous legislative processes, emerged as a new influencing circle in the process. Lastly, the study found that media organizations, in the process of developing agenda, had a strong impact on the National Assembly as a subject forming public issues and as a messenger of the legislative agenda while they played a limited role in affecting the government. This study discusses why communication in the domestic legislative process is important and what are some hindering and facilitating factors in the process.

• Journal of the Korean GEO-environmental Society
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• v.21 no.3
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• pp.5-11
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• 2020

Recently, ground pits that have been occurring frequently in urban areas are hindering traffic flow and causing property damages and loss of human life, acting as factors that are threatening the safety of citizens. Therefore, sunken ground must be quickly restored and provisions must be made for additional damage but current domestic detailed standards regarding ground pits and accurate definitions regarding causes and measures to be taken for reoccurrences are lacking. Restoration methods of sunken ground include backfilling by reusing sunken soil or other fill material and paving the road and while this is the most often used method, this only prevents ground from sinking temporarily and can not serve as a fundamental solution. Also, additional ground pits can occur on ground that is reinforced using this method due to faulty backfill material or faulty hardening. This study used Eco-friendly High-Strength Material (EHSM) as restoration material that can be used in the restoration of underground cavities that have occurred due to ground subsidence to analyze the engineered characteristics of modified dredging clay and test pieces made from changed ratios of EHSM and weathered granite soil were uniaxial compression tests were conducted and freezing-thawing tests were conducted to study strength properties according to environmental changes of restoration material, and after tests were concluded by each level, uniaxial compression tests and dynamic elasticity tests were conducted for intensity analysis. Also, to evaluate strength characteristics of the restored ground, dynamic plate load tests were conducted to verify the improvement effectiveness of the restored ground.

• Journal of The Korean Association For Science Education
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• v.20 no.4
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• pp.572-581
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• 2000

Teachers' perceptions about curricular objectives are very important to achieve given educational objectives. This study examined teachers' perceptions about priority and hinderance of science objectives. The national science curriculum stated four areas of objectives: inquiry, knowledge, attitude, and STS. A total of 76 elementary and 217 secondary teachers were responded to questionnaire developed for this study. Non-parametric statistics, such as Friedman test, Kruskal-Wallis test, and chi-square test were used by using SPSS/PC program. Teachers in general ranked the inquiry first among the four areas at their perception on the national curriculum, on themselves, and on their instructions. Elementary teachers ranked inquiry higher than secondary science teachers, while secondary science teachers ranked knowledge higher than elementary teachers. As factors hindering teachers from achiving the objectives, elementary teachers pointed out overcrowded classroom and secondary science teachers pointed out college and university entrance examination respectively.

• Korean Journal of Social Welfare
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• v.62 no.1
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• pp.155-183
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• 2010

Despite the increase in the demands on collaboration between health and social welfare, the success of such schemes have been limited. The extant literatures tends to be dominated by explanations for needs or short-term outcomes of collaboration rather than systematic follow-up research to apply to the frontline. At the same time, there is no attempt to apply the theories related to collaboration in order to discuss the situation. This study explores the factors hindering such collaborative working in the frontline, through semi-structured interviews with practitioners involved in two pilot projects. A theoretical framework (Equilibrium Model-Sensemaking, E-S model) which combined Equilibrium Model of 'Interorganizational Network' of Benson(1975) and 'Sensmaking' of Weick(1995) for conceptualiing aspects of collaborations such as working atmosphere and agency was applied to the empirical study of the Public Health and Welfare Office(1995-1999) and the Social Welfare office(2004-2006) pilot projects. Data were collected over three months from 8 pilot project areas with practitioners and managers from health and social welfare. The findings show significant regional differences between pilot areas, such as the presence of active leaders and co-location, had a major impact on the ability of practitioners to effectively integrate services. In other words, active leaders tended to influence practitioners' motivation, while co-location encouraging communication between both practitioners, and thus seemed to influence the practices of collaborative working. Furthermore, through E-S model, it is interpreted that this kind of positive experiences about collaborations may impact on the current practitioners' comprehensive perspective towards health and social welfare services in general. The findings could help policy makers consider the practical ways to break down the barriers between health and social welfare.

• International Journal of Computer Science & Network Security
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• v.21 no.3
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• pp.235-244
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• 2021

The change of the development of transport and logistics systems occurs with the active change of technology and the advent of the era of Industry 4.0. It requires modernization of approaches to the development of transport and logistics systems at the macro and micro levels. The present study aims to identify perspective directions of development and evolution, find out the existing obstacles in the integration of technological solutions of transport and logistics systems at the macro and micro levels. This study is based on a quantitative and qualitative methodology for assessing the level of integration of technologies into transport and logistics systems to study the prospects for their development at the micro level. Macroeconomic indicators of transport and logistics in the context of different regions of the world were used to quantify the development prospects. For a qualitative assessment of the development of the transport and logistics system, the case study method was used. The object of the study was selected logistics company Sensco Logistics Inc., Austin TX. At the macro level, countries with more innovative logistics sectors have stronger mechanisms for coordinating private sector activities. Simplification of administrative procedures of control and regulation by the public sector in order to facilitate trade between countries is a promising direction for the development of transport and logistics systems. Such reforms are more effective in developing a "rigid" transport infrastructure. The integration of Industry 4.0 technology solutions into the international logistics sector is defined by political and legal barriers, especially in developing countries. In low-income countries, hard and soft infrastructure reforms are hindering the development of logistics companies that provide transport services. This determines the national level of development of transport and logistics systems, and in general the global level of development of transport and logistics. In developed countries, the legal barriers to the development of new technological logistics are environmental requirements for the integration of technologies into the transport system. These trends are slowing down the development of International Logistics, which, compared to other industries, is slower to integrate Industry 4.0 technologies. This study combines macroeconomic factors that determine the prospects for the development of transport and logistics systems at the micro level.

• 한국사회정책
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• v.25 no.1
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• pp.161-194
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• 2018

The purpose of this study is to investigate the factors that interrupt the use of social security of elderly North Korean refugees. As a result of qualitative content analysis using interview data, it is found that the elderly North Korean defectors have a lower access to the social security system. The main reason for hindering the use of social security system is low awareness due to limited information channels, psychological distance to South Korean society and residents. Moreover, this psychological distance is a factor that reduces the geographical accessibility of elderly North Korean defectors by preferring to use services in specific institutions for North Korean, while South Korean elderly people can use the service elsewhere. In addition, there are many cases in which the elderly in North Korean defectors do not receive sufficient social security due to low income. On the other hand, social security systems with high accessibility of older North Korean refugees are characterized by the fact that they are provided by experts who have formed sufficient rapport with North Korean refugees. Therefore, it seems possible to improve the accessibility of elderly defectors' friendly system by professional workers with cultural competence. In addition, a multidimensional approach is needed to fully cope with the complex desires of elderly North Korean defectors and a mechanism should be set up to reflect their opinion in system operation.

• The Journal of Society for e-Business Studies
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• v.24 no.3
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• pp.19-33
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• 2019

Recently, manufacturers have been struggling to efficiently use production equipment as their production methods become more sophisticated and complex. Typical factors hindering the efficiency of the manufacturing process include setup cost due to job change. Especially, in the process of using expensive production equipment such as semiconductor / LCD process, efficient use of equipment is very important. Balancing the tradeoff between meeting the deadline and minimizing setup cost incurred by changes of work type is crucial planning task. In this study, we developed a scheduling model to achieve the goal of minimizing the duedate and setup costs by using reinforcement learning in parallel machines with duedate and work preparation costs. The proposed model is a Deep Q-Network (DQN) scheduling model and is a reinforcement learning-based model. To validate the effectiveness of our proposed model, we compared it against the heuristic model and DNN(deep neural network) based model. It was confirmed that our proposed DQN method causes less due date violation and setup costs than the benchmark methods.

• Journal of the Korean GEO-environmental Society
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• v.20 no.1
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• pp.67-74
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• 2019

Frost heave is one of the representative engineering characteristics in cold regions. In South Korea, which is located in seasonal frost area, structural damage caused by frost heave and thaw happens and the need for research on the frost heave is increasing. In this paper, newly developed transparent temperature-controllable cell is used to focus on the frost heave. Frost susceptible artificial soil is used to analyze water intake rate which is one of the important factors in frost susceptibility criteria. Frost heave rate and water intake rate have similar behavior after heave by freezing of pore water converges. O-ring installed in the upper pedestal to measure water intake rate generates side friction between the inner wall of the freezing cell and O-ring, thereby hindering frost heave. Therefore, the frost susceptibility criteria using the water intake rate is not reliable. It is appropriate to use frost heave rate which has similar behavior with water intake rate. Frost heave tests were performed under two different specimen heights. Overburden pressure, temperature gradient and dry unit weight were set under similar state. Based on laboratory testing results, frost heave is independent on the specimen height.

• Journal of Korean Elementary Science Education
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• v.43 no.1
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• pp.1-17
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• 2024

This study sought to investigate the effects of cooperative learning emphasizing interactions on science-gifted elementary students' scientific creativity. Thirty-four science-gifted elementary students were divided into an experimental class and a comparison class to compare their creativity scores quantitatively. The experimental class participated in cooperative learning emphasizing interactions, and the comparison class participated in whole class interactions. For qualitative analysis, the small group discussions were audiotaped and transcribed. The results of the study are as follows. First, cooperative learning emphasizing interactions had a positive educational effect on usefulness, which is one of the essential elements of scientific creativity. Second, as the cooperative learning progressed, the interaction between the small group members improved qualitatively. Third, the factors hindering the effectiveness of cooperative learning included negative task-unrelated statements from some of the small group members and the following operational statements to correct them. Based on these results, this study proposed some suggestions for effective cooperative learning emphasizing interactions.