• Journal of the Korean Society of Systems Engineering
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• v.19 no.2
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• pp.46-58
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• 2023

Deterministic safety analysis is a crucial part of safety assessment, particularly when it comes to demonstrating the safety of nuclear power plant designs. The traditional approach to deterministic safety analysis models is to model the nuclear core using point kinetics. However, this simplified approach does not fully reflect the real core behavior with proper moderator and fuel reactivity feedbacks during the transient. The use of Multi-Physics approach allows more precise simulation reflecting the inherent three-dimensionality (3D) of the problem by representing the detailed 3D core, with instantaneous updates of feedback mechanisms due to changes of important reactivity parameters like fuel temperature coefficient (FTC) and moderator temperature coefficient (MTC). This paper addresses a CEA ejection accident at hot full power (HFP), in which the underlying strong and un-symmetric feedback between thermal-hydraulics and reactor kinetics exist. For this purpose, a multi-physics analysis tool has been selected with the nodal kinetics code, 3DKIN, implicitly coupled to the thermal-hydraulic code, RELAP5, for real-time communication and data exchange. This coupled approach enables high fidelity three-dimensional simulation and is therefore especially relevant to reactivity initiated accident (RIA) scenarios and power distribution anomalies with strong feedback mechanisms and/or un-symmetrical characteristics as in the CEA ejection accident. The Systems Engineering approach is employed to provide guidance in developing the work in a systematic and efficient fashion.

• Steel and Composite Structures
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• v.50 no.1
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• pp.89-105
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• 2024

Multichannel analysis of surface waves (MASW) method has exhibited broad application prospects in the nondestructive detection of interfacial debonding in steel-concrete composite structures (SCCS). However, due to the structural diversity of SCCS and the high stealthiness of interfacial debonding defects, the feasibility of MASW method needs to be investigated in depth. In this study, synthetic parametric study on MASW nondestructive debonding detection for SCCSs is performed. The aim is to quantitatively analyze influential factors with respect to structural composition of SCCS and MASW measurement mode. First, stress wave composition and propagation process in SCCS are studied utilizing 2D numerical simulation. For structural composition in SCCS, the thickness variation of steel plate, concrete core, and debonding defects are discussed. To determine the most appropriate sensor arrangement for MASW measurement, the effects of spacing and number of observation points, along with distances between excitation points, nearest boundary, as well as the first observation point, are analyzed individually. The influence of signal type and frequency of transient excitation on dispersion figures from forwarding analysis is studied to determine the most suitable excitation signal. The findings from this study can provide important theoretical guidance for MASW-based interfacial debonding detection for SCCS. Furthermore, they can be instrumental in optimizing both the sensor layout design and signal choice for experimental validation.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.55-68
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• 2017

In recent years, medical practice has seen a drastic change due to the rapid, exponential expansion of scientific and medical technologies. Specially, the role of medical technologists (also known as medical laboratory scientists and/or clinical laboratory scientists) are increasing in the development of science of medical technology. As such, their responsibility has also been increasing. Therefore, given their highly specialized knowledge and skills, they are not regarded solely as doctor's assistants. Their independence and deeper specialization have been increasing, as they perform medial practices under the guidance of doctors or dentists pursuant to the "Act on Medical Service Technologists." From a legal point of view, medical guidance and scope of work were examined. As a conclusion, the definition of doctor's superintendency on the "Act on Medical Service Technologists" is required, and the qualification for the Korean license examination and their roles should be stated clearly. Moreover, communications among health professions regarding the roles of medical technologists are necessary to further facilitate clarification of their role. There is a need for independent legislation to expand the field of medical technologists and to strengthen their professionalism.

• Membrane Journal
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• v.27 no.3
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• pp.248-254
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• 2017

In order to secure the reliability of pathogenic microorganisms such as Cryptosporidium and Giaridia, which are chlorophilic protozoans, membrane filtration systems have been widely used in water purification process. hese integrity tests are classified into direct and indirect methods. Based on the bubble point theory, the pressure-based test in the direct method is presented in the USEPA Guidance Manual with sensitivity to detect a minimum size of pathogenic microorganisms of $3{\mu}m$ or more. Indirect methods are widely used in that they are capable of continuous operation in on-line state, but there is a very low sensitivity of damage detection compared to the direct method, and there is a limit that can not specify the damage area, so it is necessary to improve this sensitivity. In this study, we compared the LRVDIT and UCL values according to the type of membrane defect, number of fiber breaks, and initial set pressure value through the Integrity Test by Pressure Decay Test (PDT).

• Journal of Technologic Dentistry
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• v.31 no.4
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• pp.45-52
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• 2009

This study is analyzed to conduct better on-site practices with recognizing importance of the clinical practice of Dept. of dental technology and use it as a basic material in the clinical practice. Target people who are students studying dental technology in D college in Daegu were questioned by survey. Study results below 1. Average score of the survey about satisfaction of the operating method of clinical practice shows 3.26. In detail elements, 'credit assignment(10 credits)' is 3.65 as the highest score, 'execution period(vacation)' is 3.50, 'choice of the clinical practice organization' is 3.25, 'measures after practice' is 2.98 and 'pre-education' is 2.98 as the lowest score. 2. Through the real clinical practice, 'experience of new equipments and technology' is 3.64 as the highest score, 'choice of lecturer' is 3.61, 'guidance way' is 3.49, 'contents properness' is 3.44, 'environment of practice organization' is 3.36, 'evaluation way' is 3.35 and 'practical use of the evaluation material' is 3.18 as the lowest score. 3. The average score of survey about satisfaction after clinical practice of the participated students is 3.46 that is higher than both 'satisfaction about operating method(3.26)' about clinical practice of college and 'satisfaction about organization(3.44)' about environment of dental craft organizations and labs, guidance way of lecturer and evaluation. 4. In the improvement of distribution of the clinical practice evaluation, in the 'practice organization: college' viewpoint, '7:3' is 35.77% as the highest response, '6:4' is 25.20%, '8:2' is 22.76% and '4:6' is 16.26 in regular sequence. 5. In site evaluation reflection of clinical practice, 50% reflection is 32.93% as the highest percentage, 60% reflection is 26.83%, 20% reflection is 20.73% and 80% reflection is 6.10% in regular sequence. In attendance score, it shows percentage of reflecting 50% and 40% is 26.98%, students wanting to reflect 30% is 25.40%, reflecting 10% is 20.63% and no reflecting is 0%. In result of the analyzed data, clinical practice has to be studied more in considering that clinical practice is important point in education of Dept. of Dental Technology and also problems in college and on-site practice need improvements.

• Journal of the Korea Society for Simulation
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• v.18 no.4
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• pp.9-20
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• 2009

Navigation system providing route-guidance and traffic information is one of the most widely used driver-support system these days. Most of the navigation system is based on the 2D map paradigm so the information is ed and encoded from the real world. As a result it imposes a cognitive burden to the driver to interpret and translate the ed information to real world information. As a new concept of navigation system, augmented-reality navigation system (AR navigation) is suggested recently. It provides navigational guidance by imposing graphical information on real image captured by camera mounted on a vehicle in real-time. The ultimate goal of navigation system is to assist the driving task with least driving workload whether it is based on the abstracted graphic paradigm or realistic image paradigm. In this paper, we describe the comparative studies on how map navigation and AR navigation affect for driving tasks by experimental research. From the result of this research we obtained a basic knowledge about the two paradigms of navigation systems. On the basis of this knowledge, we are going to find the optimal design of navigation system supporting driving task most effectively, by analyzing characteristics of driving tasks and navigational information from the human-vehicle interface point of view.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.543-553
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• 2013

In Korea, there have been many studies and progresses on various types of pilot scale or commercialized field scale Best Management Practices(BMP) during the last 10 years. Runoff characteristics of diffuse pollutants from different land uses are well identified and documented. However, for the coastal area connected directly with shoreline, runoff patterns and management schemes of non-point pollution were not fully studied. Recently, coastal area is emerging as a new development axis especially in west coast side of Korea such as Incheon city and Chungnam province, thus urbanized area rapidly increased but there are no buffer zones and BMP facilities to aim at preventing direct discharge of the first flush into coastal sea and beaches. In this study, parking area in Deacheon harbor, Boryeong City in Chungnam Province was selected and rainfall runoff was monitored for two year period in order to examine run-off features from which proper type of BMP suitable for coastal area is proposed. Coastal area usually has a low ground water level and consists of plain land, so that large scale BMP such as storm water retention pond and wetland requiring great excavation works is not best management plan. In addition, monitoring study shows that storm water from the paved parking area has a high salinity compared with those in storm water from the inland. High salinity is detrimental for the vegetation. Therefore, BMP employing least vegetative cover and also in terms of maintenance is a good option such as infiltration trench and porous pavement.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.59-70
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• 2021

This paper studies and analyzes the effect of illustrations in picture books on time representation with fictional picture books as the study scope. In this paper, the time type of picture books can be divided into time point, timeline and time rhythm, referring to case analysis from time symbolic elements, picture layout and picture sequence respectively. First of all, time symbolic elements are referred to the time point and time rhythm. The materialized time symbolic element is things that can directly represent time and trigger associations with time; the color symbolic element means the color changes in the real world within a certain time; the contrast of light and shadow corresponds to the changes in a day. Fast-moving objects will be presented with dashed or blurred lines, while static, stable and slow objects will be depicted with solid lines. Secondly, the picture layout of illustrations in picture books is suitable for representing the content of the timeline and describing the sequence or causality of events. Finally, the picture sequence can represent the timeline, time rhythm and "synchronicity". It will make use of visual logic to win readers' trust in time information expressed in pictures, and then follow and connect viewpoints on the basis of adapting to reading habits. The essence of time representation in picture books is to express time by space, and use different combinations of elements in space and visual guidance to convey time information.

• Journal of the HCI Society of Korea
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• v.2 no.2
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• pp.35-43
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• 2007

This paper presents a system for image matching and recognition based on image feature detection and description techniques from artificial satellite photographs. We propose some kind of parameters from the varied environmental elements happen by image handling process. The essential point of this experiment is analyzes that affects match rate and recognition accuracy when to change of state of each parameter. The proposed system is basically inspired by Lowe's SIFT(Scale-Invariant Transform Feature) algorithm. The descriptors extracted from local affine invariant regions are saved into database, which are defined by k-means performed on the 128-dimensional descriptor vectors on an artificial satellite photographs from Google earth. And then, a label is attached to each cluster of the feature database and acts as guidance for an appeared building's information in the scene from camera. This experiment shows the various parameters and compares the affected results by changing parameters for the process of image matching and recognition. Finally, the implementation and the experimental results for several requests are shown.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.49
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• pp.3-41
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• 2011

In this article, the author have studied on main revisions and some recommendations of the Incoterms(R) 2010. Main revisions are as belows. 1. Two new Incoterms rules -DAT and DAP- have replaced the Incoterms 2000 rules DAF, DES, DEQ and DDU. 2. New classification of the Incoterms(R) 2010 are adopted. First class is Rules for any mode or modes of transport(EXW, FCA, CPT, CIP, DAT, DAP and DDP belong to this class.) and second class is rules for sea and inland waterway transport(FAS, FOB, CFR and CIF belong to this class.). 3. Incoterms(R) 2010 rules formally recognizes that they are available for application to both international and domestic sale contracts. 4. The Guidance Notes and Introduction are not part of the actual Incoterms(R) 2010 rules. 5. Under the FOB, CFR and CIF, all mention of the ship's rail as the point of delivery has been omitted in preference for the goods being delivered when they are "on board" the vessel. 6. Incoterms(R) 2010 rules include the obligation to 'procure goods shipped' as an alternative to the obligation to ship goods in the relevant Incoterms rules. 7. Incoterms(R) 2010 rules give electronic means of communication the same effect as paper communication. 8. Incoterms(R) 2010 rules have allocated obligations between the buyer and seller to obtain or to render assistance in obtaining security-related clearances. such as chain-of custody information. Some recommendations are as belows. 1. The parties must incorporate the Incoterms(R) 2010 rules into their contract of sale. 2. The parties must choose the appropriate Incoterms(R) 2010 rules. 3. Specify the place or port as precisely as possible in their contract of sale. 4. Remember that Incoterms(R) 2010 rules do not give the parties a complete contract of sale. 5. Incoterms(R) 2010 rules do not prohibit alteration of Incoterms rule, but there are dangers in so doings. In order to avoid any unwelcome surprises, the parties would need to make the intended effect of such alterations extremely clear in their contract.