• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.3
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• pp.598-625
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• 2014

To support the procedure for determining an optimal liquefaction cycle for FLNG FEED, an ontological modeling method which can automatically generate various alternative liquefaction cycles were carried out in this paper. General rules in combining equipment are extracted from existing onshore liquefaction cycles like C3MR and DMR cycle. A generic relational model which represents whole relations of the plant elements has all these rules, and it is expressed by using the system entity structure (SES), an ontological framework that hierarchically represents the elements of a system and their relationships. By using a process called pruning which reduces the SES to a candidate, various alternative relational models of the liquefaction cycles can be automatically generated. These alternatives were provided by XML-based formats, and they can be used for choosing an optimal liquefaction cycle on the basis of the assessments such as process simulation and reliability analysis.

• Journal of Electrochemical Science and Technology
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• v.15 no.3
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• pp.427-435
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• 2024

Here we introduce a new method for characterizing the constant phase element (CPE) in electrochemical systems using cyclic voltammetry (CV), presenting an alternative to the conventional electrochemical impedance spectroscopy (EIS) approach. While CV is recognized for its diagnostic capabilities in electrochemical analysis, it traditionally encounters difficulties in accurately measuring CPE systems due to a lack of clear linearity with scan rates, unlike capacitors. Our research demonstrates a linear relationship between current and scan rate on a log-log plot, enabling the calculation of n and Y₀ values for CPE from the slopes of these linear relationships. For validation of our method, it is applied to two kinds of capacitors and the results agree with those measured by EIS. Although EIS is known to be accurate in measuring CPE systems, our alternative approach offers a timely and reasonably precise diagnostic tool, balancing between ease of use and accuracy, especially beneficial for preliminary assessments before conducting further in-depth analysis.

• Nuclear Engineering and Technology
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• v.56 no.9
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• pp.3925-3932
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• 2024

During outages at nuclear power plants, much more care for radiation workers against internal exposure should be ensured given that more hot particles exist relative to the amount during normal operation. If fuel-type hot particles (FTHP) are inhaled, they can cause more severe health risks compared to activation-type hot particles (ATHP), which contain ⁶⁰Co, due to the alpha-emitting nuclides within FTHPs. The activities of difficult-to-measure nuclides within FTHPs inhaled by workers are inferred by the age-dating technique using a¹⁴¹Ce/¹⁴⁴Ce ratio as measured by whole-body counters. However, this method may be limited to outages that last for only a few months due to the short half-life (32.5 days) of ¹⁴¹Ce. We studied the feasibility of utilizing ²⁴¹Am, a nuclide with a long half-life of 432.6 years, as an alternative to ¹⁴¹Ce. Additionally, we improved the performance of a stand-type whole-body counter for low-energy gamma spectroscopy to meet the criterion (RMSE ≤0.25) specified in ANSI/HPS N13.30-2011 by employing an artificial neural network (ANN). This study can contribute to more rapid and accurate internal dose assessments for workers who have inhaled FTHPs during long-term outages at nuclear power plants.

• Archives of Plastic Surgery
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• v.41 no.3
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• pp.285-289
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• 2014

The composite anterolateral thigh flap with vascularized fascia lata has emerged as a workhorse at our institution for complex Achilles defects requiring both tendon and soft tissue reconstruction. Safe elevation of this flap, however, is occasionally challenged by absent or inadequate perforators supplying the anterolateral thigh. When discovered intraoperatively, alternative options derived from the same vascular network can be pursued. We present the case of a 74-year-old male who underwent composite Achilles defect reconstruction using a segmental rectus femoris myofascial free flap. Following graduated rehabilitation, postoperatively, the patient resumed full activity and was able to ambulate on his tip-toes. At 1-year follow-up, active total range of motion of the reconstructed ankle exceeded 85% of the unaffected side, and donor site morbidity was negligible. American Orthopaedic Foot and Ankle Society and Short Form-36 scores improved by 78.8% and 28.8%, respectively, compared to preoperative baseline assessments. Based on our findings, we advocate for use of the combined rectus femoris myofascial free flap as a rescue option for reconstructing composite Achilles tendon/posterior leg defects in the setting of inadequate anterolateral thigh perforators. To our knowledge, this is the first report to describe use of this flap for such an indication.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.10
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• pp.879-887
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• 2003

Buildings with heating and cooling systems have been increased, since the requirement of thermal comfort for residents is grown. Heating and cooling systems, have been changed from two separate systems to one multi-function system which includes both heating and cooling. Especially, heat pump heating and cooling system has been adopted for general classrooms in schools since education environment improvement project has been launched. This research suggests the best option for the heat pump heating and cooling system in educational buildings through economic assessments for four alternative systems based on electric heat pump (EHP) and gas engine driven heat pump (GHP), which are most widely used for elementary, middle and high schools. The model buildings are in the Y high school which has 24 classes of new construction building, which will be built soon. Annual energy consumption for alternative systems uses BECS 3.10, which can be used for system simulation.

• Journal of Environmental Impact Assessment
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• v.33 no.4
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• pp.164-174
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• 2024

Recently, many offshore wind farm project plans and environmental impact assessments have been conducted in Korea. However, despite having different characteristics from onshore wind farm, there is a lack of alternative setting and evaluation methods suitable for this. Accordingly, this study attempted to derive implications for the alternative setting and evaluation method suitable for the domestic situation through overseas guideline and case analysis. Through the result of the analysis, it was possible to examine the process of the alternative setting and evaluation method for offshore wind farm, and through this, detailed considerations and methodology were found. Even overseas, the methodology for alternative setting and evaluation has not yet been clear, and the methodology used for onshore wind farm has been improved and developed. In Korea, it is necessary to prepare a system for setting and evaluating alternatives to such offshore wind farm projects, and research in various fields is required to carry out them reasonably and efficiently. For the successful promotion of domestic offshore wind farm projects, it is thought that continuous efforts to increase environmental and social acceptance are necessary along with the promotion of related research reflecting the implications derived from overseas cases.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.4
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• pp.81-94
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• 1999

Organization change projects such as Business Process Redesign(BPR) have been implemented by many firms for enhancing their organizational performance. However, management is reluctant to initiate these projects due to enterprise-wide impact and steeper project cost than the traditional system development projects. Thus, there emerges a need to accurately assess the value of the redesigned organizational process for the successful implementation of BPR projects. The purpose of this study is to assess the value of process redesign in the point of resource utilization and allocation, and cycle time and cost reduction. The candidate process and the design alternatives are identified from organizational requirements analysis. The variables and their relations are defined to perform task activity analysis, bottleneck analysis, cycle cost analysis, and resource utilization analysis. A Case study of a manufacturing company indicates that the assessments method proposed in this study is a promising approach to identify the business alternative process that lead to the highest organizational performance.

• English Language & Literature Teaching
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• no.5
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• pp.149-189
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• 1999

Assessment can be defined as any method used to understand the current knowledge that a student possesses. Assessment may influence decisions about grades, placement, instructional needs, and curriculum. Therefore, the purpose of assessment is to identify how the students think and know, to diagnose the difficulties they face, and to reflect the result of assessment on teaching. But the traditional multiple-choice test failed to evaluate and teach higher-level thinking and problem-solving skills. In this context, performance assessment is being required as an alternative assessment to get better understanding about what the students can do as well as what they know. This article points out some weaknesses of traditional assessments, and comments on the theoretical background and necessity of performance assessment. And it presents more specific information about performance assessment and some examples. It is certain that performance assessment is student-centered and future-oriented. But performance assessment can't be the surest and best way of evaluating the students' abilities. We are just on the way of another experimental stage for improving teaching methodology. More supplementary analyses and further improvements are needed.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.84-87
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• 2005

The citrus industry represents a major sector of agribusiness in Jeju successfully nurtured by the local governmental farm bureaus for the past three decades. However, in the face of increasing imports effected under the international free trade agreement, the continuous economic viability of the island’s citrus industry is no longer assured. Thus, it entails exploration and development of new agribusiness potentials that are supplemental and/or alternative to the citrus industry. In this presentation, I will discuss two projects of such potentials. (i) Under the tripartite collaboration among Kumho Life and Environmental Science Laboratory, Cheju National University and South Jeju County, genetically engineered turfgrass cultivars possessing both herbicide- and shade-tolerances (gene pyramiding) are currently at final phase of phenotype evaluations and environmental safety assessments. (ii) Fig fruits with longer shelf-life are being developed with support from Jeju HiTech Industrial Development Institute (HiDI) and at its initial phase of development.

• Korean Journal of Veterinary Research
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• v.47 no.2
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• pp.259-263
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• 2007

The choice of input distribution in quantitative risk assessments modeling is of great importance to get unbiased overall estimates, although it is difficult to characterize them in situations where data available are too sparse or small. The present study is particularly concerned with accommodation of uncertainties commonly encountered in the practice of modeling. The authors applied parametric and non-parametric bootstrap simulation methods which consist of re-sampling with replacement, in together with the classical Student-t statistics based on the normal distribution. The implications of these methods were demonstrated through an empirical analysis of trade volume from the amount of chicken and pork meat imported to Korea during the period of 1998-2005. The results of bootstrap method were comparable to the classical techniques, indicating that bootstrap can be an alternative approach in a specific context of trade volume. We also illustrated on what extent the bias corrected and accelerated non-parametric bootstrap method produces different estimate of interest, as compared by non-parametric bootstrap method.