• 제어로봇시스템학회논문지
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• 제5권6호
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• pp.714-723
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• 1999

This paper presents a short-term scheduling algorithm for the operation of steelmaking processes. The scope of the problem covers refining of the hot iron transferred form a blast furnace, ladle treatment, continuous casting, hot-rolling, and coiling for the final products that should satisfy the given demand. The processing time at each unit depends on how much the batch amount is treated, and te dedicated intermediate storage with finite capacity between the units is considered. Resource constraints and initial amount of each state are incorporated into the presented scheduling model for the algorithm of on-line scheduling. We propose amixed integer linear programming (MILP) model with two objectives for the scheduling. The first is to maximize the total profit while atisfying the due date constraint for each product. And the second is to minimize the total processing time, makespan, while satisfying the demand for each product. Especially, we observe the effect of penalizing the intermediate storage and the inventory level of the final product on the scheduling results.

• Bulletin of the Korean Chemical Society
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• 제15권5호
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• pp.394-399
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• 1994

The catalytic mechanism of malonyl-CoA synthetase from Rhizobium trifolii was investigated by the steady state kinetics and intermediate identification. Initial velocity studies and the product inhibition studies with AMP and PPi strongly suggested ordered Bi Uni Uni Bi Ping-Pong Ter Ter system as the most probable steady state kinetic mechanism of malonyl-CoA synthetase. Michaelis constants were $0.17{\pm}0.04 {\mu}M,\;0.24{\pm}0.18 {\mu}M\;and\;0.045{\pm}0.26 {\mu}$M for ATP, malonate and CoA, respectively. The TLC analysis of the $^{32}P-labelled$ products in reaction mixture containing $[{\gamma}-^{32}P]$ ATP in the absence of CoA showed that PPi was produced after the sequential addition of ATP and malonate. Formation of malonyl-AMP, suggested as an intermediate in the kinetically deduced mechanism, was confirmed by the analysis of $^{31}P-NMR$ spectra of AMP product isolated from the $^{18}O$ transfer experiment using $[^{18}O]$malonate. Two resonances were observed, corresponding to AMP labelled with zero and one atom of $^{18}O$, indicating that one atom of $^{18}O$ transferred from $[^{18}O]$malonate to AMP through the formation of malonyl-AMP. Formation of malonyl-AMP was also confirmed through the TLC analysis of reaction mixture containing $[{\alpha}-^{32}P]$ATP. These results strongly support the ordered Bi Uni Uni Bi Ping-Pong Ter Ter mechanism deduced from the initial velocity and product inhibition studies.

• 상하수도학회지
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• 제26권3호
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• pp.453-461
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• 2012

The degradation characteristics of TCE by Ferrate(VI) oxidation have been studied. Ferrate(VI) were prepared by electrochemical method. The degradation efficiency of TCE in aqueous solution was investigated at various pH values, Ferrate(VI) doses and aqueous solution temperature values. GC-ECD was used to analyze TCE. TCE was degraded rapidly by ferrate(VI) in aqueous solution, Also, the experimental results showed that TCE removal efficiency increased with the increase of Ferrate(VI) doses. The effect of pH was investigated and the maximum degradation efficiency was obtained at pH 7. And intermediate products were identified by GC-MS techniques. Ethyl Chloride, Dichloroethylene, Chloroform, 1,1-dichloropropene, Trichloroacetic acid and Trichloroethane were identified as a reaction intermediate, and $Cl^-$ was identified as an end product.

• 상하수도학회지
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• 제26권1호
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• pp.37-46
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• 2012

The degradation characteristics of TCE by Ferrate(VI) oxidation have been studied. The degradation efficiency of TCE in aqueous solution was investigated at various pH values, Ferrate(VI) doses, initial concentrations of TCE and aqueous solution temperature values. GC-ECD was used to analyze TCE. The optimum conditions of TCE degradation were obtained pH 7.0 and $25^{\circ}C$ in aqueous solution. Also, the experimental results showed that TCE removal efficiency increased with the decrease of initial concentration of TCE. And intermediate products were identified by GC-MS techniques. Ethyl Chloride, Chloroform, Ethylene, 1,2-dichloroethane and 1,1,2-trichloroethane were identified as a reaction intermediate, and $Cl^-$ was identified as an end product.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.303-308
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• 1992

In this study, we propose a shared storage system which is more efficient policy than MIS(Mixed Intermediate Storage) policy for relatively rare storage system and can be called CIS(Common Intermediate Storage) policy. Using this strategy, we develop a new completion time algorithm and apply it to two kinds of optimal or near optimal scheduling method; combinatorial search and simulated annealing method. We also extend this strategy to other storage policy, for example MIS policy, with PLC(Programmable Logic Controller) logic and on/off action of electronic valves. It thus can be accepted as a basic form of FMS(Flexible Manufacturing System) for operating various storage policies. Finally we suggest the interlocking block to compansate for the shortcoming of CIS policy, i.e, complication of operation and safety, resulting in a basic batch process automation mode.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1994년도 추계학술대회 논문집
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• pp.141-148
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• 1994

In order to improve the productivity of cold forging at low production cost, an integrated system's approach is necessary in handling the material preparation and the optimum process design, considering the forming machines, tooling, and operation including quality control. As the first step toward this approach, an expert system for multi-stage cold forging process design for fasteners with various head geometries is developed using Prolog language on IBM 486 PC. For effective representation of the complex part geometries, the system uses the multiple element input, and the forward inference scheme in determination of the initial billet size and intermediate forging steps. In order to determine intermediate steps, the basic empirical rules for extrusion, heading, and trimming were applied. The required forming loads and global strain distributions at each forging step were calculated and displayed on the PC monitor. The designed process sequence drawing can be obtained by AutoCAD. The developed system will be useful in reducing trial and error of design engineers in determining the diameter and height of the initial cylindrical billet from the final product geometry and the intermediate necessary sequences.

• Bulletin of the Korean Chemical Society
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• 제6권5호
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• pp.280-284
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• 1985

Kinetic measurements of the 5-nitrofurfural-hydrazine reaction in various pH ranges of aquous solution were carried out by ultraviolet spectrophotometry at $25^{\circ},\;35^{\circ}\;and\;45^{\circ}C$. The observed rate of the reaction varies with the change in pH, which gives characteristic "bell-type" rate acidity profile. The maximum rate is shown in the vicinity of pH 4. This reaction procceds with rate-determining attack of hydrazine on the 5-nitrofurfural at low pH and undergoes a change in rate-determining step to dehydration of the addition intermediate as pH increases. The reaction has a "reactant-like transition state" which precedes intermediate in low pH and "product-like transition state" which follows it in neutral pH. The geometry of 5-nitrofurfural-hydrazine intermediate was estimated with PCILO method associated with CNDO/2 scheme.

• 대한방사선기술학회지:방사선기술과학
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• 제46권2호
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• pp.151-157
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• 2023

The purpose of this study was to develop an assist device that could correct and support patient position during biopsy on computed tomography (CT) using 3D printing technology. The development method was conducted in the order of 3D design, 3D output, intermediate evaluation for product, final assist device evaluation. The 3D design method was conducted in the order of prior research data survey, measurement, primary modeling, 3D printing, output evaluation, and supplementary modeling. The 3D output was the 3D printer (3DWOX 2X, Sindoh, Korea) with additive manufacturing technology and the polylactic acid (PLA) materials. At this time, the optimal strength was evaluated to infill degree of product as the 3D printing factors into 20%, 40%, 60%, and 80%. The intermediate evaluation and supplementation was measured noise in the region of interest (ROI) around the beam hardening artifact on the CT images. We used 128-channel MDCT (Discovery 75 HD, GE, USA) to scan with a slice thickness of 100 kVp, 150 mA, and 2.5 mm on the 3D printing product. We compared the surrounding noise of the final 3D printing product with the beginning of it. and then the strength of it according to the degree of infill was evaluated. As a result, the surrounding noise of the final and the early devices were measured at an average of 3.3 ± 0.5 HU and 7.1 ± 0.1 HU, respectively, which significantly reduced the noise of the final 3D printing product (p<0.001). We found that the percentage of infill according to the optimal strength was found to be 60%. Finally, development of assist devices for CT biopsy will be able to minimize artifacts and provide convenience to medical staff and patients.

• 한국IT서비스학회지
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• 제7권4호
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• pp.301-317
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• 2008

Product-related services in manufacturing industry are different from typical services in service industry. Product-related services ensure proper product functioning, provide additional repurchase, and offer attractive margin Product-related services in manufacturing industry are not core activity but taking supporting roles, while services in typical service industry are core parts. The purpose of this study is to investigate the role of communication in linking IT and product-related logistics service in manufacturing industry. The relationships among IT, communication, logistics service and business performance are explored using a path analysis. The empirical research reveals that higher degree of IT usability leads to increased communication, and in turn, communication affects logistics service, and ultimately business performance. In addition, this study shows communication plays an intermediate role in linking IT to logistics service.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.3053-3056
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• 2009

The title compound, ${\alpha},{\alpha}$-dichloro-o-methylacetophenone, was prepared and its photochemical behavior was investigated. Addition of an extra chlorine at alpha position to the carbonyl showed many different features from photochemical reactivities of mono chloro analogue, 2,5-dimethylphenacyl chloride. In benzene, a rearrangement product with a formal 1,5-Cl shift and a reduction product were formed beside indanone. In methanol, solvolysis and cyclization of a common dienol intermediate occurred at comparable reaction rates.