• 한국연소학회:학술대회논문집
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• 2013.06a
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• pp.91-94
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• 2013

Commercial computational fluid dynamics (CFD) codes traditionally rely on the computational efficiency of the simplified single-film apparent char kinetic model to predict char particle temperatures and char conversion rates in pulverized coal boilers. The aim of this study is to evaluate the reliability of the single-film apparent kinetic model and to suggest the importance of proper use of this model. For this, a parametric study was conducted with a consideration of main parameters such as Stefan flow, product species, particle evolution, and kinetic parameters.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.184-189
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• 2007

Concerns about food safety continue to rise and under this situation, governments of some countries have reinforced their regulations more strictly for food safety. In order to prevent food safety incidents or, at least to minimize the impact, the preparedness is very important. As a consequence of this, traceability system has become an essential tool for food safety. Recently, it requires more prevention-based food safety control system. One of the most generally used systems for food safety control is Hazard Analysis and Critical Control Point (HACCP). Both traceability and HACCP systems can be integrated through Electronic Product Code (EPC) Sensor Network technologies which have four value propositions. In this paper, we will introduce the concept of product and process traceability system (P2TS) through the integration of three systems to improve food safety management. The final aim is to find out the added values of the P2TS.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1799-1802
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• 2003

The commercial success of a new product is influenced by the time to market. Shorter product leadtimes are of importance in a competitive market. This can be achieved only if the product development process can be realized in a relatively small time period. New cutting inserts are developed by a time consuming trial and error process guided by empirical knowledge of the mechanical cutting process. The effect of previous cutting on chip formation and the surface residual stresses has been studied. The chip formation is not affected much. There is only a minor influence from the residual stress on the surface from tile first cutting on the second pass chip formation. Thus, it is deemed to be sufficient to simulate only the first pass. The influence of the cutting speed and feed on the residual stresses has been computed and verified by the experiments. It is shown that the state of residual stresses in the workpiece increases with the cutting speed. This paper presents experimental results which can be used for evaluating computational models to assure robust solutions. The general finite element code ABAQUS/Standard has been used in the simulations. A quasi-static simulation with adiabatic heating was performed. The path for separating the chip from the workpiece is predetermined. The agreement between measurements and calculation is good considering the simplifications introduced.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.3
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• pp.175-180
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• 2004

In order to vitrify the combustible dry active waste (DAW) generated from Korean Nuclear Power Plants, a glass formulation development based on waste composition was performed. A borosilicate glass, DG-2, was formulated to vitrify the DAW in an induction cold crucible melter (CCM). The processability, product performance, and volume reduction effect of the candidate glass were evaluated using a computer code and were measured experimentally in the laboratory and CCM. The glass viscosity and electrical conductivity as the process parameters were in the desired ranges. Start-up and maintaining glass melt of the candidate glass were favorable in the CCM. The product of the glass product such as chemical durability, phase stability, and density was satisfactory. The vitrification process using the candidate glass was also evaluated assuming that it was operated as economically as possible.

• Korean Journal of Computational Design and Engineering
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• v.15 no.6
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• pp.449-459
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• 2010

Recently, not only marine PLM (Product Lifecycle Management) system but also an effective outfitting BOM (Bill of Material) management has been attracted by many shipyards. In particular, efficient outfitting design is being one of major issues in shipyards since most of currently designed marine vessels have more complex outfitting system than ever. Furthermore, each outfitting system has huge number of parts that should be arranged based upon the procurement and installation plan. Outfitting BOMs evolve into different forms according to the product development phases during basic design; detail design; and production design. Therefore, it is very difficult to maintain a consistent BOM data during the design phases. In order to express the evolution of product structures and the information of outfitting along the ship design, we suggested UID (Unique ID) code system. The UID (Unique ID) is used in order to create the relationship within evolutional BOMs of each design stage. It utilizes as the procedure of weight calculation for procurement BOM during each design stage. Thereafter, in order to demonstrate suggested outfitting BOM management technique, we suggested a prototype. In the prototype system, suggested features of outfitting BOM are implemented.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.1
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• pp.73-84
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• 2023

This study aims to identify the current sizing communication issues of menswear on retail websites and to suggest an effective size information presentation method. Based on sales frequency and awareness in the Korean menswear market, 22 brand websites were selected, and size-related information was investigated using 7 types of representative apparel items. The current diverse types of size codes had limitations in delivering actual product size information. Many websites preferred to display garment dimensions rather than basic body measurements, which is the suggested size designation method in Korean Standard. The websites posted fit model photos and customer reviews. However, the body size specifications, which consumers can use as a useful reference, were often omitted. There was also a high uncertainty in product size selection, with only the basic body measurement information listed, and there was a high deviation of garment dimensions within the same basic body measurements. The product size distribution did not match actual Korean body types. Based on the findings, we suggested improved effective sizing communication methods. These methods will contribute to a better online shopping environment for both consumers and retail sellers.

• Nuclear Engineering and Technology
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• v.49 no.2
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• pp.395-403
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• 2017

An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, $Q_V(r)$, of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of $Q_V(r)$ and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.12 no.3
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• pp.41-63
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• 2004

The area covered by product liability in broadest sense is so vast that an attempt to analyse all its impact on the aviation world risk. Every effort has been made to confine our review of subject a closely as possible to its influence on aircraft manufacturers, airlines and passengers, in spite of strong connections with other spheres of commercial. Product Liability in aviation is the liability of aircraft's manufacturer, processor or non-manufacturing seller for injury to the person or property of a buyer or third party caused by a product which has been sold. Here-in a product is aircraft, third party is passengers who suffered damage by defective design, defective construction, inadequate instructions for handling in aircraft. Whenever a product turns out to be defective after it has been sold, there are under Anglo-American law three remedies available against the aircraft's manufacturer (1) liability for negligence (2) breach of warranty (3) strict liability in tort. There are Under continental law Three remedies available against the aircraft's manufacturer (1) liability for defective warranty (2) liability for non-fulfillment of obligation (3) liability in tort. It is worth pointing out here an action for breach of warranty or for defective warranty, for non-fulfillment of obligation is available only to direct purchaser on the basis of his contract with the aircraft's manufacturer, which of course weakness its range and effectiveness. An action for tort offers the advantage of being available also to third parties who have acquired the defective product at a later stage. In tort, obligations are constituted not only by contract, but also by stature and common law. In conclusion, There in no difference in principle of law. In conclusion I would like to make few suggestions regarding the product liability for aircraft's manufacturer. Firstly, current general product liability code does not specify whether government offices(e.g. FAA) inspector conducted the inspection and auditory certificate can qualify as conclusive legal evidence. These need to be clarified. Secondly, because Korea is gaining potential of becoming aircraft's manufacturer through co-manufacturing and subcontracting-manufacturing with the US and independent production, there needs legislation that can harmonize the protection of both aircraft's manufacturers and their injured parties. Since Korea is in primary stage of aviation industry, considerate policy cannot be overlooked for its protection and promotion. Thirdly, because aircraft manufacturers are risking restitution like air-carriers whose scope of restitution have widened to strict and unlimited liability, there needs importation of mandatory liability insurance and national warranty into the product liability for aircraft's manufacturers. Fourthly, there needs domestic legislation of air transportation law that clearly regulates overall legal relationship in air transportation such as carrier & aircraft manufacturer's liability, and aviation insurance.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2
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• pp.207-215
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• 2020

The feasibility of rare earth (RE) removal process via oxidation reactions with UCl₃ was investigated using the HSC Chemistry code to reduce the concentrations of RE in transuranic (TRU) products. The composition and thermodynamic data of TRU and RE elements contained in the reference spent fuel were examined. The reactivity was evaluated by calculating equilibrium data considering oxidation reactions with UCl₃. Both RE removal rate and TRU recovery rate were evaluated for the two cases, wherein TRU products with different RE concentrations were used. When TRU products were reacted with UCl₃, selective oxidation was driven by the difference in the Gibbs free energy of each element. The calculation results imply that the TRU/RE ratio of the final product can be increased by removing RE elements while maintaining the maximum recovery rate of TRU, which is accomplished by controlling the amount of UCl₃ injected. Since the results of this study are based on thermodynamic equilibrium data, there are many limitations to apply to the actual process. However, it is expected to be used as an important data for the process design to supply the TRU product of pyroprocessing to SFR's fuel demanding low RE concentrations.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.6
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• pp.109-117
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• 2016

The most important mission of RFID reader is identify EPC (Electronic Product Code) of RFID tag of products that located within distinguishable range of RFID reader. RFID reader transmits query message to RFID tags through wireless channel and RFID tags send unique EPC to response its query message simultaneously. therefore tag collision occurred frequently. RFID tags collision resolution algorithm required to apply RFID technology to various industries. In this paper, we propose enhanced M-ary algorithm that collision bits location is used by not only RFID reader but also tags. the main feature of the proposed algorithm is that integrate multiple query message of M-ary QT algorithm to the single query message by analyze multiple response messages from tags. the simulation results show that the proposed algorithm give better performance than M-ary QT algorithm in terms of the number of query-response, identification efficiency and communication overhead.