• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.28-31
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• 2001

Recently, in order to satisfy the consumer's demand the life cycle and the lead-time of a product is to be shortened. It is thus important to reduce the time and cost in manufacturing trial products. Several techniques have been developed and successfully commercialized in the market RPM(Rapid Prototyping and Manufacturing). However, most commercial systems currently use resins or waxes as the raw materials. So, the limited mechanical strength for functional testing is regarded as an obstacle towards broader application of rapid prototyping techniques. To overcome this problems, high-speed machining technology is being investigated worldwide for rapid manufacturing and even for direct rapid tooling application. In this paper, some fundamental experiments and analyses are carried out to obtain the filling time, materials, method, and process parameters for HisRP process. HisRP is a combination process using high-speed machining technology with automatic filling. In filling process, Bi58-Sn alloy is chosen because of the properties of los-melting point, low coefficient of thermal expansion and enviromental friendship. Also the use of filling wire is of advantage in term of simple and flexible mechanism. Then the rapid manufacturing product, for example a skull, is machined for aluminum material by HisRP process with an automatic set-up device of 4-faces machining.

• Journal of the Korea Society for Simulation
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• v.24 no.2
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• pp.19-29
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• 2015

M&S techniques are utilized for various purposes on the national defense, and its importance is increasing than ever. For analyzing RAM (Reliability, Availability and Maintainability) of weapon system, using M&S techniques can be more effective and practical way than deterministic approach, because M&S approach can consider uncertain variables and various constraints in the ILS (Integrated Logistics support) field. For design of ILS M&S, we first set up a purpose of M&S, attributes of real system and other similar ILS M&S tool. Then, we convert real system into model which consists of mathematical formula and logical expression. In this thesis, we introduce modeling procedures of M&S that describes total life cycle of 'OO guided weapon system' and the contents proposed in this paper can provide references for developing other M&S tool.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.4
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• pp.463-469
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• 2011

BIM(Building Information Modeling) technologies should be applied for the construction life cycle to maximize its efficiency, but the utilization for the construction phase has been significantly lower than that for the planning and design phase. Recently, some of BIM techniques such as 3D design review, 4D schedule management and so on are being introduced for efficient managing to the big national construction projects. In this study, the utilization plans of BIM are presented for the construction phase of civil engineering facilities. The methods of utilization of BIM are discussed for each type of construction, and the techniques applied to the Seoul Subway Lot No. 919 are analyzed for checking the applicability and usability. In particular, a web construction management system based on BIM can help field engineers, headquarters and contractors to use BIM more effectively, and it can be extended to maintenance phase for more efficiencies.

• The Journal of Health Technology Assessment
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• v.1 no.1
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• pp.22-26
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• 2013

Objectives: Balancing benefits and risks through the drug life cycle has been discussed for many decades. The objective of this study was to review the processes and tools currently proposed for benefit-risk assessment of medicinal drugs. It aimed to establish scientific and efficient drug safety management system based on the synthetic analysis of benefit-risk evidence. Methods: We conducted a review of exiting literatures published by regulatory agencies or initiatives. Not only quantitative methodologies but also qualitative method were compared to understand their key characteristics for the benefit and risk assessment of drugs. Results: Recently, benefit-risk assessments have more structured approaches to decision making as part of regulatory science. Regulatory agencies such as European Medicines Agency, FDA have prepared plans to apply benefit-risk assessment to regulatory decision making. Also many initiatives such as IMI (Innovative Medicine Initiative) have conducted research and published reports about benefit-risk assessment. For benefit-risk assessment, four kinds of methods are necessary. Frameworks such as BRAT (Benefit Risk Action Team) framework, PrOACT-URL provide guidance for the whole process of decision-making. Metrics are measurements of risk benefit. The estimation techniques are methods to synthesis and combine evidences from various sources. The utility survey techniques are necessary to explicit preferences of various outcome from stakeholders. Conclusion: There is the lack of widely accepted, validated model for benefit-risk assessment. Nor there is an agreement among academia, industry, and government on methods for the quantitative valuation. It is also limited by available evidence and underlying assumptions. Nevertheless, benefit-risk assessment is fundamental to improve transparency, consistency and predictability for decision making through the structured systematic approaches.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.19-23
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• 2001

In addition to landfilling and incineration, waste minimization and recycling have become priorities in Taiwan's municipal waste management strategies over the past 10 years. Major recycling initiatives being implemented in Taiwan include producer responsibility, "pay-as-you-throw, " and mandatory sorting provisions. Currently, the producer responsibility regime established under the Waste Disposal Act and administered by the Environmental Protection Administration (EPA) requires that manufacturers or importers of listed items, including containers, batteries. cars, motorcycles ("scooters"), tires, oil, televisions, refrigerators, air conditioners, washing machines, computers, and printers, pay recycling fees to government recycling funds. EPA then uses the recycling funds to subsidize collection and recycling. The 2001 recycling fund budget totals NT$57 billion (NT$35 = US$l). Under the producer responsibility regime, EPA-designated retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143 kg in 1997 to 0.978 kg in 2000. Targeting a 10% recycling rate for municipal waste in 2001. EPA plans to research and develop new recycling techniques, expand the scope of producer responsibilities, and strengthen existing municipal recyclable collection programs. To this end, among other initiatives, EPA has prepared a draft "Resource Recycling and Reuse Act" that would complement the existing producer responsibility programs by incorporating into the current recycling framework the concept of product life-cycle management.

• Journal of the Korean Society for Railway
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• v.13 no.1
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• pp.71-77
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• 2010

It is increasing annually that the cost for bridge Maintenance Repair & Rehabilitation (MR&R) in developed countries. Based on Intelligent Technology, Bridge Management System (BMS) is developed for optimization of Life Cycle Cost (LCC) and reliability to predict long-term bridge deteriorations. However, such data are very limited amongst all the known bridge agencies, making it difficult to reliably predict future structural performances. To alleviate this problem, an Artificial Neural Network (ANN) based Backward Prediction Model (BPM) for generating missing historical condition ratings has been developed. Its reliability has been verified using existing condition ratings from the Maryland Department of Transportation, USA. The function of the BPM is to establish the correlations between the known condition ratings and such non-bridge factors as climate and traffic volumes, which can then be used to obtain the bridge condition ratings of the missing years. Since the non-bridge factors used in the BPM can influence the variation of the bridge condition ratings, well-selected non-bridge factors are critical for the BPM to function effectively based on the minimized discrepancy rate between the BPM prediction result and existing data (deck; 6.68%, superstructure; 6.61%, substructure; 7.52%). This research is on the generation of usable historical data using Artificial Intelligence techniques to reliably predict future bridge deterioration. The outcomes (Long-term Bridge deterioration Prediction) will help bridge authorities to effectively plan maintenance strategies for obtaining the maximum benefit with limited funds.

• Korean Journal of Construction Engineering and Management
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• v.16 no.3
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• pp.101-112
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• 2015

In the 1950s, the concept of configuration management (CM) was started by the US Department of Defense (DOD). Later, it has begun to be applied in aerospace, software, engineering, construction, and nuclear power industry. However, configuration management (CM) in the Korean nuclear industry was firstly utilized in 2006 only for selected parts of facilities, while the US nuclear industry has applied CM for the facilities' entire systems since 1990s. Furthermore, configuration management (CM) is in its conceptual stage in the Korean nuclear industry because of ambiguous CM concepts, lacks of CM professional manpower, non-computerization, and inadequacy of CM procedures and processes. In order to address this issues, seven industries (including defense, aerospace, software, engineering, architecture, civil engineering, nuclear power) that utilize the concept of configuration management (CM) were compared and analyzed based on the CM purpose, technique, and life-cycle perspectives. By an extensive literature review and expert interviews, this paper developed a framework of configuration management (CM) for the nuclear industry. And also, a list of functions based on life-cycle stages and CM techniques are developed for clarifying CM framework in order to promote practical applications.

• Journal of the Korean Electrochemical Society
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• v.1 no.1
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• pp.45-51
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• 1998

[ $AB_2-type$ ] alloy, one kind of hydrogen storage alloys used as an anode of Ni-MH batteries, has large discharge capacity but has remaining problems regarding initial activation, cycle life and self-discharge. This study investigates the effects of Cr-addition and fluorination after La-addition on $Zr_{0.7}Ti_{0.3}V_{0.4}Mn_{0.4}Ni_{1.2}$, composition $AB_2-type$ alloy. EPMA and SEM surface analysis techniques were used and the crystal structure was characterized by XRD analysis. In addition, electrodes were fabricated out of the alloys and characterized by constant current cycling test, electrochemical impedance spectroscopy and potentiodynamic polarization. Cr-addition was found to be effective to cycle life and self-discharge but ineffective to initial activation due to formation of stable oxide film on surface. Fluorination after La-addition to the alloys improved initial activation remarkably due to formation of highly reactive particles on surface.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.470-478
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• 2019

As the growth of the domestic defense industry is remarkable regarding technology level and export size, technology protection is necessary. Particularly, there is a need to apply anti-tamper measures to prevent critical technologies from illegally being taken out of weapon systems. However, there is no security protection strategy and system built yet in ROK. Precedent studies discussed the trend analysis and technical research for specific protective techniques, and the application of anti-tamper using limited procedures was provided. Recently, methods of how to select the technology for protection were studied based on risk management. Nonetheless, these studies cannot be associated with the acquisition process for the whole life-cycle, having difficulty with actual development and evaluation of the weapon systems. The objective of our study is to derive the system requirements of the weapon system for which anti-tamper measures have been determined to apply. Specifically, requirements items suitable for the development of anti-tamper weapon systems were derived based on ISO/IEC 19790, the CMVP standard for the development and verification of cryptographic modules. Also, its utilization in technical reviews and test & evaluations was presented. The usefulness of the research results was confirmed through inductive inference and comparative evaluation. The result can be expected to play a role in initiating extensive activities needed for technology protection of the weapon systems.

• Nutrition Research and Practice
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• v.11 no.6
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• pp.470-478
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• 2017

BACKGROUND/OBJECTIVE: Orostachys japonicus A. Berger (Crassulaceae) has been used in traditional herbal medicines in Korea and other Asian countries to treat various diseases, including liver disorders. In the present study, the anti-fibrotic effects of O. japonicus extract (OJE) in cellular and experimental hepatofibrotic rat models were investigated. MATERIALS/METHODS: An in vitro hepatic stellate cells (HSCs) system was used to estimate cell viability, cell cycle and apoptosis by MTT assay, flow cytometry, and Annexin V-FITC/PI staining techniques, respectively. In addition, thioacetamide (TAA)-induced liver fibrosis was established in Sprague Dawley rats. Briefly, animals were divided into five groups (n = 8): Control, TAA, OJE 10 (TAA with OJE 10 mg/kg), OJE 100 (TAA with OJE 100 mg/kg) and silymarin (TAA with Silymarin 50 mg/kg). Fibrosis was induced by treatment with TAA (200 mg/kg, i.p.) twice per week for 13 weeks, while OJE and silymarin were administered orally two times per week from week 7 to 13. The fibrotic related gene expression serum biomarkers glutathione and hydroxyproline were estimated by RT-PCR and spectrophotometry, respectively, using commercial kits. RESULTS: OJE (0.5 and 0.1 mg/ mL) and silymarin (0.05 mg/mL) treatment significantly (P < 0.01 and P < 0.001) induced apoptosis (16.95% and 27.48% for OJE and 25.87% for silymarin, respectively) in HSC-T6 cells when compared with the control group (9.09%). Further, rat primary HSCs showed changes in morphology in response to OJE 0.1 mg/mL treatment. In in vivo studies, OJE (10 and 100 mg/kg) treatment significantly ameliorated TAA-induced alterations in levels of serum biomarkers, fibrotic related gene expression, glutathione, and hydroxyproline (P < 0.05-P < 0.001) and rescued the histopathological changes. CONCLUSIONS: OJE can be developed as a potential agent for the treatment of hepatofibrosis.