• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.3
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• pp.169-179
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• 2011

There are two types of nuclear reactors in Korea and they are PWR type and CANDU type. The safe management of the spent fuels from these reactors is very important factor to maintain the sustainable energy supply with nuclear power plant. In Korea, a reference disposal system for the spent fuels has been developed through a study on the direct disposal of the PWR and CANDU spent fuel. Recently, the research on the demonstration and the efficiency analyses of the disposal system has been performed to make the disposal system safer and more economic. PWR spent fuels which include a lot of reusable material can be considered being recycled and a study on the disposal of HLW from this recycling process is being performed. CANDU spent fuels are considered being disposed of directly in deep geological formation, since they have little reusable material. In this study, based on the Korean Reference spent fuel disposal System (KRS) which was to dispose of both PWR type and CANDU type, the more effective CANDU spent fuel disposal systems were developed. To do this, the disposal canister for CANDU spent fuels was modified to hold the storage basket for 60 bundles which is used in nuclear power plant. With these modified disposal canister concepts, the disposal concepts to meet the thermal requirement that the temperature of the buffer materials should not be over $100^{\circ}C$ were developed. These disposal concepts were reviewed and analyzed in terms of disposal effective factors which were thermal effectiveness, U-density, disposal area, excavation volume, material volume etc. and the most effective concept was proposed. The results of this study will be used in the development of various wastes disposal system together with the HLW wastes from the PWR spent fuel recycling process.

• The Journal of Society for e-Business Studies
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• v.17 no.4
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• pp.69-93
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• 2012

Various influence-related relationships in Social Network Services (SNS) among users, posts, and user-and-post, can be expressed using links. The current research evaluates the influence of specific users or posts by analyzing the link structure of relevant social network graphs to identify influential users. We applied the concept of mutual interactions proposed for ranking semantic web resources, rather than the voting notion of Page Rank or HITS, to blogosphere, one of the early SNS. Through many experiments with network models, where the performance and validity of each alternative approach can be analyzed, we showed the applicability and strengths of our approach. The weight tuning processes for the links of these network models enabled us to control the experiment errors form the link weight differences and compare the implementation easiness of alternatives. An additional example of how to enter the content scores of commercial or spam posts into the graph-based method is suggested on a small network model as well. This research, as a starting point of the study on identifying influential users in SNS, is distinctive from the previous researches in the following points. First, various influence-related properties that are deemed important but are disregarded, such as scraping, commenting, subscribing to RSS feeds, and trusting friends, can be considered simultaneously. Second, the framework reflects the general phenomenon where objects interacting with more influential objects increase their influence. Third, regarding the extent to which a bloggers causes other bloggers to act after him or her as the most important factor of influence, we treated sequential referencing relationships with a viewpoint from that of PageRank or HITS (Hypertext Induced Topic Selection).

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1266-1270
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• 2004

Humic substances include several biological active and inactive compounds that are commonly used for improving soil fertility. Use of humic substances in swine diets is a novel concept. Humic substances contain 8,700 mg/kg of iron but its bioavailability is unknown. This study was conducted to test the bioavailability of iron in humic substances for nursery pigs. One hundred twenty five pigs (Newsham, Colorado Springs, CO) were not given supplemental iron while nursing for 21 d. Pigs were weaned on d 21 and allotted to one of five treatments (four control treatments with different levels of supplemented iron; 0, 30, 70 and 88 mg/kg from ${FeSO}_4$ and one treatment with 70 mg/kg iron from humic substances). Pigs were fed diets for 5 wk ad libitum and water was accessible freely. Body weight and feed intake were measured weekly. Blood samples were taken from pigs on d 28 to measure the number of red blood cells and hemoglobin concentration. Pigs fed a diet with the humic substances grew faster (p<0.05) during the first week postweaning, but performance was not different during the entire 5 wk period. Feed intake and gain/feed were the same among treatments. The slope ratio technique was used to estimate relative iron bioavailability. The concentration of blood hemoglobin did not respond to dietary iron levels using this model. However, the number of red blood cells (106/$\mu$l) was modeled by 4.438+0.017${\times}$ 'ron (mg/kg) from ${FeSO}_4$'0.012${\times}$'ron (mg/kg) from the humic substances' Based on the comparison between the slopes (0.012 from humic substances and 0.017 from ${FeSO}_4$), iron in humic substances was 71% as available as the iron in ${FeSO}_4$. The slopes for dietary feed intake of ${FeSO}_4$ and the iron in humic substances did not differ (p>0.05). Humic substances can replace ${FeSO}_4$ as an alternative iron source for pigs at 71% relative bioavailability.

• Journal of Korea Water Resources Association
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• v.42 no.12
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• pp.1029-1038
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• 2009

Recently, it is expected that small hydropower (SHP) could potentially provide sufficient amounts of alternative energy in Korea where there is an abundance of potential sites and where social efforts are being made to reduce the emissions of green house gases. In the past, the resources survey for SHP development has been carried out using onsite surveys and paper maps, which incurred a great deal of time and cost. Furthermore, the tools for decision making such as determining development priorities or evaluating feasibility have been considered only economic aspect and focused on the performance characteristics of power generation. However, as the concept of sustainable development has been being advanced in recent years, especially focused on human-social, environmental and ecological in addition to economical sector; the consideration of these multiple criteria has become essential for sustainable SHP development. This study aims to propose the spatial multi-criteria decision making (MCDM) methodology for determining priorities among a number of locations on the planning stage of SHP development using AHP and GIS. The proposed methodology is applied for determining development priorities among the SHP locations in Cho River basin and this study presents the detailed spatial information data and the results of development priorities. As a fundamental work, this study will be beneficial to the future activation of SHP development and will help the decision making in evaluating the feasibility of SHP development.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.139-150
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• 2010

In recent years, more generic drug products became available. The current regulation for assessing the bioequivalence of two drug formulations is based on the concept of average bioequivalence. This approach has been indicated to be insufficient for assessing switchability between two drug formulations and US FDA has adopted individual bioequivalence as one of the bioequivalence criterion since 2001. The US FDA recommends that individual bioequivalence be assessed based on $2\;{\times}\;4$ crossover design, while a $2\;{\times}\;3$ crossover design may be used as an alternative design to reduce the length and cost of the study. In this paper, a statistical procedure for assessment of individual bioequivalence under $3\;{\times}\;2$ crossover designs is proposed and some statistical points are discussed with $2\;{\times}\;3$ crossover design and $2\;{\times}\;3$ extra-reference design through simulation studies.

• Clean Technology
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• v.7 no.1
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• pp.13-25
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• 2001

With fast advancement of fine machineries and semiconductor industries in recent decades, the ultra-cleaning of organic chemicals, submicron particles from contaminated unit equipments and products such as silicon wafers becomes one of the most important steps for further advancement of such industries. To date, two kinds of ultra cleaning techniques are used; one is the wet-cleaning and the other is the dry cleaning. In case of wet cleaning, removal of organic contaminants and submicron particles is made by DIW with additives such as $H_2O_2$, $H_2SO_4$, HCl, $NH_4OH$ and HF, etc. While the wet cleaning method is most widely adopted for various occasions, it is inevitable to discharge significant amount of toxic waste waters in environment. Dry cleaning is an alternative method to mitigate environmental pollution of the wet cleaning with maintaining comparable degree of cleaning to the wet cleaning. Although there are various concept of dry cleaning have been devised, the dry cleaning with environmentally-benign solvent such as carbon dioxide proven to show high degree of cleaning from the contaminated porous surface as well as from the bare surface. Thus, special global attention has been placing on this technique since it has important advantages of simple process schemes and no environmentally concern, etc. Thus, this article critically reviews the state-of-the-art of the supercritical fluid drying with emphasis on the thermo-physical characteristics of the supercritical solvent, environmental gains compared to other dry cleaning methods, and the generic aspects of the basic design and processing engineering.

• Archives of design research
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• v.13 no.3
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• pp.281-292
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• 2000

Today, the rapid economic growth and emerging new trends have been changed radically throughout the society and they especially have affected the changes of life-style and the diversity of residents'demands in housing life. This changes of life have brought the shift in family form from traditional type, thus new phase of nuclear family means that it makes on the whole, variable family forms such as single family, non-blood one, a generation one and so on. It therefore is time that we should not only explore current housing plans, but envisage concept of new living space to satisfy latent need of the occupants. But the forms, in spite of the diversity of user's needs and the change of life-style, of many houses as many apartment and tenement houses supplied so far have been clearly limted, and housing policy of the mass-supply causes monotonous space composition, over-occupation and non-changeability. Now, the collective houses have some limits owing to the commoness and assemblage, but they have failed to keep up with the variable and changeable life-style of residents. These problems, to put it concretely, lead to increasing needs for the number of rooms in proportion to family members, for the change of behavior using the space. We therefore need to propose the new living space. As the current plans for designing house are based on the average life-style of people, they can not cope with variable demands of the resident. For that reason, this paper will propose the manual space system as an alternative for it and the goal is to suggest new furniture system which we need to create the flexibility of living space.

• Journal of The Korean Association of Information Education
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• v.5 no.3
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• pp.415-431
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• 2001

Recently, the biggest interest in education, education using ICT(Information and Communication Technology) is being emphasized excessively and only the practical side is being embossed on the research about it, so it is causing worry that it is inclined to technical use. In this study, we tried to prepare the strategy for efficient use of ICT in search of theoretical level on use of ICT as an alternative plan for these problems. First, we defined the concept of efficient use of ICT and fixed high thinking of human as basic authority cited for deduction of strategy and analyzed Integrated Thinking Model of Iowa State Dept. of Education. We categorized synthetic thinking for efficient use of ICT through these works. In addition, we classified ICT for efficient use into software area, hardware area, and use skill area, and observed each concepts and interrelationship. And we argued 'Decision Authority of Relation between Thinking Area and ICT Area' to examine relation between synthetic thinking category and each area of ICT, and we established concretization of that, 'Analysis Matrix for Deduction of ICE-EUS'. We tried to guarantee the propriety of deduction process and the clearness of deduction result through this works. Through this process we finally deduct the ICT-EUS(Efficient-Use Strategy of ICT) about learning resources, learning tools, tutee, searching, communication, production and presentation of ICT area. ICT-EUS is expected to provide possibility of being able to enhance the efficiency and effectiveness of achievement of learning goals through cognitive analysis about learning resources, tools and use skills beyond simple use of ICT.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.4
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• pp.283-295
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• 2007

The technical feasibility of a pyroprocessing of PWR spent fuels to recover nuclear fuel materials, uranium and transuranic elements group(TRU), was examined in this study. Also its applicability as a new fuel cycle technology in terms of non-proliferation was investigated. First, various unit processes were combined to a pyroprocess. Then the flow aspects of such materials of issue as uranium, transuraniums, rare earth, noble metals and heat generating elements were examined on the flowsheet, which was obtained by the assumptions on the basis of various experimental results in this work or separation data collected from literatures. Consequently, the calculated results of the material balance for the whole process showed that uranium and TRU could be recovered as products by 98.0 % and 97.0 %, respectively, from a PWR spent fuel while removing the other elemental groups into radioactive wastes. On the one hand, the TRU product was found to emit a considerable amount of ${\gamma}$-ray as well as neutrons favorably contributing to the strategy of proliferation resistance.

• Journal of Veterinary Clinics
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• v.28 no.6
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• pp.555-561
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• 2011

Laparoscopic surgery is a well-established alternative to open surgery across disciplines. However, in veterinary medicine, laparoscopic surgery in dogs was rarely reported because of small abdominal size for multiple ports insertion. The concept of single-incision laparoscopic surgery (SILS) is to perform the entire laparoscopic operation through a single incision rather than conventional multiple small skin incisions. Indirect evidence of potential benefits of SILS, decreases operative morbidity related to reduction in port size, already exists. Therefore, this study was performed to evaluate the safety and feasibility of the modified form of SILS using flexible endoscope in Cholecystectomy before clinical adoption. A 2 cm single periumbilical incision was performed, and flexible endoscope was introduced into the abdominal cavity. A laparoscopic grasper was inserted into the abdominal cavity for the traction of gall bladder. Cystic duct and artery were ligated by 5 mm Hem-o-lok$^{(R)}$. Then, gall bladder was dissected and resected from the liver with 5 mm Autonomy Laparo-Angle Maryland dissector and endoscopic needle knife. Resected gall bladder was wrapped by using specimen pouch and was retrieved through abdominal incision from the cavity. All three gall bladders were successfully removed. Hematological changes were not observed during examination periods. No leakage sign was identified at necropsy. The flexible endoscope, as distinct from conventional rigid laparoscope, allows the visualization from various angles and the wide range of motion, result in less crowding.