• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.113-122
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• 2008

Emerging of wireless sensor networks results in several modeling and design issues on the network simulations. In previous works, most researchers have used three evaluation approaches such as analysis method, computer simulation and real test-bed measurement in order to verify the performance of wireless sensor networks. Among these approaches, analysis method is widely used since the other approaches have significant drawbacks such as limitation of network power, computational problem of distribute processing and complication of debugging process. However, the analysis method also shows poor performance when it deals with complex operations in huge wireless sensor networks. Thus, in this paper, we design and develop SMAC and AODV protocols by using Ptolemy tool in order to improve the simulation performance. The developed Ptolemy actor can be easily adapted to compare and evaluate the various protocols for wireless sensor networks.

• The Journal of Korean Association of Computer Education
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• v.6 no.4
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• pp.71-83
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• 2003

This study is aimed to develop and evaluate different approaches for cyber education. The project involved the development of sample cyber education programs using different design approaches, with built-in evaluation mechanisms. The different design approaches depend on what delivery technologies are involved. In the First Generation, the delivery technologies use text, flash and animation, whereas the synchronized content to video and audio are used in the Second and the Third Generations but the difference is the delivery method used by the videoclip. Tests were carried out through self-assessment to measure and analyze the efficient teaching. The results show that the Third generation technologies were the most effective method for cyber education. However, since the Third generation program is developed in multimedia, it tends 10 require higher development costs, and more advanced hardware and software as well as a higher bandwidth for network. Therefore, the research indicates that the development of technical supports, like loading speed, has to be solved simultaneously with the development of multimedia products for effective cyber education.

• Journal of Environmental Policy
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• v.8 no.3
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• pp.163-180
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• 2009

This study attempts to investigate the preference uncertainty of respondents involved in stating their Willingness to Pay (WTP). For the Contingent Valuation Method (CVM) survey, we employed two approaches using two split samples. The respondents of one sample were given the opportunity to express intensity of preference through Multi-bounded Discrete Choice (MBDC) WTP questions, while those in the other sample were given Dichotomous Choice (DC) WTP questions. By incorporating the two elicited degrees of preference uncertainty into examining the WTP responses, we compared the two approaches. In comparing the DC model with the MBDC model, the mean WTP for the DC model was similar to PRYES in the MBDC Model. We concluded that the MBDC model estimates the various mean WTP while considering the preference uncertainty.

• School Mathematics
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• v.10 no.4
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• pp.557-571
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• 2008

The objective of this paper is to study De Morgan's thoughts on teaching and learning negative numbers. We studied De Morgan's point of view on negative numbers, and analyzed his didactical approaches for negative numbers. De Morgan make students explore impossible subtractions, investigate the rule of the impossible subtractions, and construct the signification of the impossible subtractions in succession. In De Morgan' approach, teaching and learning negative numbers are connected with that of linear equations, the signs of impossible subtractions are used, and the concept of negative numbers is developed gradually following the historic genesis of negative numbers. Also, we analyzed the strengths and weaknesses of the De Morgan's approaches compared with the mathematics curriculum.

• Journal of Korean Society on Water Environment
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• v.38 no.4
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• pp.177-189
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• 2022

Nature-based Solutions (NbS) are defined as practical and technical approaches to restoring functioning ecosystems and biodiversity as a means to address socio-environmental challenges and provide human-nature co-benefits. This study reviews NbS-related literature to identify its key characteristics, techniques, and challenges for its application in climate-adaptive water management. The review finds that NbS has been commonly used as an umbrella term incorporating a wide range of existing ecosystem-based approaches such as low-impact development (LID), best management practices (BMP), forest landscape restoration (FLR), and blue-green infrastructure (BGI), rather than being a uniquely-situated practice. Its technical form and operation can vary significantly depending on the spatial scale (small versus large), objective (mitigation, adaptation, naturalization), and problem (water supply, quality, flooding). Commonly cited techniques include green spaces, permeable surfaces, wetlands, infiltration ponds, and riparian buffers in urban sites, while afforestation, floodplain restoration, and reed beds appear common in non- and less-urban settings. There is a greater lack of operational clarity for large-scale NbS than for small-scale NbS in urban areas. NbS can be a powerful tool that enables an integrated and coordinated action embracing not only water management, but also microclimate moderation, ecosystem conservation, and emissions reduction. This study points out the importance of developing decision-making guidelines that can inform practitioners of the selection, operation, and evaluation of NbS for specific sites. The absence of this framework is one of the obstacles to mainstreaming NbS for water management. More case studies are needed for empirical assessment of NbS.

• Journal of Animal Science and Technology
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• v.65 no.6
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• pp.1111-1123
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• 2023

This study aims to present a more systematic and developmental research direction by classifying animal-mediation related research trends published in Korea. We analyzed the research trends of 68 domestic animal-mediation programs published in 26 journals over the past 24 years under the premise of the necessity of animal-assisted therapy, which considered a very effective intervention method in the practice areas of various subjects. Therefore, this study examines the year of publication of animal-mediation related research conducted in various academic fields from 1998 to 2022, research data sources, characteristics of research subjects, types of interventions and research topics, research design and intervention sessions, intervention methods, and ethical consideration statements. The results of this study are as follows: First, in the source of research and research trends by year, the number of papers published in animal-related societies was the highest at 34 (50%); the number of studies has been steadily increasing since the mid-2000s. Second, regarding research trends by subject, 45 (66%) were general subjects, 23 (34%) were medically diagnosed, 60 (88%) were selected through pre-evaluation, and 8 (12%) were requested. Third, regarding research trends by method, 27 (40%) of the pretests were conducted before and after the experiment-control group, and only 3 (4%) of the 68 papers were examined later. Fourth, regarding research trends by content, depression (25%) was the most frequently applied variable, and regarding intervention sessions, 53 (78%) were less than 12 sessions. Fifth, regarding research trends and ethical consideration statements by treatment approach method, 58 cases (85%) of individual treatment approaches and 10 cases (15%) of intervention approaches integrated with individual treatment approaches, and 23 cases (34%) of studies with ethical consideration statements or the Institutional Review Board's (IRB) approval. Based on the study results, the implications and research directions of animal-assisted therapy related research are discussed.

• Structural Engineering and Mechanics
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• v.48 no.6
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• pp.849-878
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• 2013

This paper consists of two parts, which broadly examines solution techniques abilities for the structures with geometrical nonlinear behavior. In part I of the article, formulations of several well-known approaches will be presented. These solution strategies include different groups, such as: residual load minimization, normal plane, updated normal plane, cylindrical arc length, work control, residual displacement minimization, generalized displacement control, modified normal flow, and three-parameter ellipsoidal, hyperbolic, and polynomial schemes. For better understanding and easier application of the solution techniques, a consistent mathematical notation is employed in all formulations for correction and predictor steps. Moreover, other features of these approaches and their algorithms will be investigated. Common methods of determining the amount and sign of load factor increment in the predictor step and choosing the correct root in predictor and corrector step will be reviewed. The way that these features are determined is very important for tracing of the structural equilibrium path. In the second part of article, robustness and efficiency of the solution schemes will be comprehensively evaluated by performing numerical analyses.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.4 s.247
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• pp.393-401
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• 2006

The influences of stress triaxiality on ductile fracture have been investigated for various specimens and structures. With respect to a transferability issue, recently, the interests on local approaches reflecting micromechanical specifics are increased again due to rapid progress of computational environments. In this paper, the applicability of the local approaches has been examined through a series of finite element analyses incorporating modified GTN and Rousselier models as well as fracture toughness tests. The ductile crack growth of nuclear carbon steels is assessed to verify the transferability among compact tension (CT) specimens with different in-plane size. At first, the basic material constants were calibrated for standard CT specimens and used to predict fracture resistance (J-R) curves of larger CT specimens. Then, the in-plane size effects were examined by comparing the numerically estimated J-R curves with the experimentally determined ones. The assessment results showed that the in-plane size effect should be considered for realistic engineering application and the damage models might be used as useful tool for ductile fracture evaluation.

• Explosives and Blasting
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• v.23 no.3
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• pp.75-82
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• 2005

Many blasting engineers develope their own approach to define how to blast different rockmass properties. The problem is that most of these approaches haven't been formalized in any systematic manner and they depend mainly on casual observation of local conditions by an experienced blaster. In this paper blastability index developed by Lilly is adopted to induce powder factor for blast design considering local conditions. With this approach blastability scheme can be considered joint properties as well as rockmass represented local conditions. This approach is also expected to supplement the shortcomings of existing blast design approaches.

• The Korean Nurse
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• v.32 no.5
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• pp.93-105
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• 1994

Nursing is indeed a practice discipline with experiential learning in clinical practice areas comprising an overwhelming portion of a Nursing Student's education. The statement is used to provide a basis for discussion of some issues involved in relation to clinical nursing education. However the lack of substantial research in the area of clinical nursing education would suggest that this 'heart' of the nursing student's professional education has olng been ignored. The purpose of this study is to critically review and analysis then suggest effective approaches of clinical nursing education. First. the curriculum can be developed by faculty consistently. Curriculum design begins with the writing of philosophy and the selection of objectives for the program. The philosophy must include a statement of beliefs and intrinc values about human being. nursing and teaching learning process. Second. faculty practice can be narrowed practice-theory gaps. Third. clinical teaching strategies can be used many different methods in order to facilitate development of clinical judgement and decision making. Fourth, clinical teacher's rols can influence student's learning attitude and intrinsic value; relating to students as mature individuals; creating an atomosphere where in the student felt comfortable approaching the instructor; providing support crisis situations. Fifth. clinical nursing evaluation can be developed the integrated models.