• Industrial Engineering and Management Systems
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• v.14 no.1
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• pp.44-57
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• 2015

In recent years, for the purpose of solving the problem regarding environment protection and resource saving, certain measures and policies have been promoted to establish a reverse supply chains (RSCs) with material flows from collection of used products to reuse the recycled parts in production of products. It is necessary to analyze behaviors of RSC members to determine the optimal operation. This paper discusses a RSC with a retailer and a manufacturer and verifies the behavior strategies of RSC members which may change over time in response to changes parameters related to the recycling promotion activity in RSC. A retailer takes two behaviors: cooperation/non-cooperation in recycling promotion activity. A manufacturer takes two behaviors: monitoring/non-monitoring of behaviors of the retailer. Evolutionary game theory combining the evolutionary theory of Darwin with game theory is adopted to clarify analytically evolutionary outcomes driven by a change in each behavior of RSC members over time. The evolutionary stable strategies (ESSs) for RSC members' behaviors are derived by using the replicator dynamics. The analysis numerically demonstrates how parameters of the recycling promotion activity: (i) sale promotion cost, (ii) monitoring cost, (iii) compensation and (iv) penalty cost affect the judgment of ESSs of behaviors of RSC members.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.62-68
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• 2015

PURPOSE. The purpose of this research was to evaluate the amount of reosseointegration after counter torquing (reverse torque) and transposing the installed implants at different times. MATERIALS AND METHODS. This study was done on ten tibiae of five cross-bred dogs. At the first day one implant was installed in each tibia. After one week half of the implants were randomly counter torqued (1WCT) and the other half were explanted and reimplanted in a new juxtaposition site (transposed)(1WT). At the same time three new implants were installed in each dog, one of them was considered as one week control (1WC) and remaining two as 8 week groups (8WCT&8WT). After eight weeks the 1WCT and 1WT implants were loosened by counter torque and the quantity of needed force for liberation was measured with the digital device (BGI). At the same time one implant was installed in each dog as eight week control (8WC) and the same protocol was repeated for 8 week groups after another 8 weeks. RESULTS. All implants were osseointegrated. Mean quantities of osseointegration in case groups indicated better amounts rather than control groups. CONCLUSION. Counter torque or transposition of the installed implants one week or eight weeks after the implantation did lead to osseointegration.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.12
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• pp.1308-1313
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• 2004

Proton irradiation technology was used for the improvement of power diode switching characteristics. Proton irradiation was carried out at the energies of 2.32 MeV, 2.55 MeV, 2.97 MeV so that the projection range of irradiated proton would be at the metallurgical junction, depletion region and neutral region of pn diode, respectively. Dose conditions were varied into three conditions of 1${\times}$10$^{11}$ cm$^{-2}$ , 1${\times}$10$^{12}$ cm$^{-2}$ , 1${\times}$10$^{13}$ cm$^{-2}$ at each condition of energies. Characterization of the device was performed by I-V(current-voltage), C-V(capacitance-voltage) and trr(reverse recovery time) measurement. At the optimum condition of irradiation, the reverse recovery time of device has been reduced about 1/5 compared to that of original un-irradiated device.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.236-236
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• 2011

본 연구 축전 결합형 고주파 플라즈마(CCP) 식각장비에 펄스 직류(Pulse DC) 전원을 인가하여 오실로스코프(oscilloscope)를 분석하여 전기적 특성을 평가하는 것이다. 펄스 직류전원 플라즈마 시스템에서는 다양한 변수를 이해하여야 한다. 본 실험에서 사용한 공정 변수는 Pulsed DC Voltage 300~500 V, Pulsed DC reverse time $0.5{\sim}2.0{\mu}s$, Pulsed DC Frequency 100~250 kHz 이었다. 실험 결과를 정리하면 1) Pulsed DC Voltage 가 증가할수록 Input voltage의 최대값은 336~520 V, 최소값은 -544~-920 V로 변하여 피크 투 피크 (peak to peak)값은 880~1460 V로 증가였다. Input current 또한 최대값은 1.88~2.88 A, 최소값은 -0.84~-1.28 A로 변하여 피크 투피크 값은 2.88~4.24 A로 증가하였다. 이는 척에 인가되는 전류와 파워의 증가를 의미한다. 2) Pulsed DC reverse time이 증가하면 Input voltage와 Input current값이 증가했다 (Input voltage의 피크 투 피크 값은 1200~1440 V, Input current의 피크 투 피크 값은 3.56~4.56 A). 3) Pulsed DC frequency가 증가하면 주기가 짧아져 Input voltage와 Input current값이 증가 한다 (Input voltage의 피크 투 피크 값은 900~1320 V, Input current의 피크 투 피크 값은 2.36~3.64 A). 결론적으로 펄스 직류 플라즈마의 다양한 전기적 변수들은 반응기 내부에 인가되는 Input voltage와 Input current의 값에 큰 영향을 준다는 것을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.371-377
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• 2012

The present study describes medium-chain-length polyhydroxyalkanoates (mcl-PHAs) production by the Pseudomonas Gl01 strain isolated from mixed microbial communities utilized for PHAs synthesis. A two-step fed-batch fermentation was conducted with glucose and waste rapeseed oil as the main carbon source for obtaining cell growth and mcl-PHAs accumulation, respectively. The results show that the Pseudomonas Gl01 strain is capable of growing and accumulating mcl-PHAs using a waste oily carbon source. The biomass value reached 3.0 g/l of CDW with 20% of PHAs content within 48 h of cultivation. The polymer was purified from lyophilized cells and analyzed by gas chromatography (GC). The results revealed that the monomeric composition of the obtained polyesters depended on the available substrate. When glucose was used in the growth phase, 3-hydroxyundecanoate and 3-hydroxydodecanoate were found in the polymer composition, whereas in the PHAs-accumulating stage, the Pseudomonas Gl01 strain synthesized mcl-PHAs consisting mainly of 3-hydroxyoctanoate and 3-hydroxydecanoate. The transcriptional analysis using reverse-transcription real-time PCR reaction revealed that the phaC1 gene could be transcribed simultaneously to the phaZ gene.

• Membrane Journal
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• v.11 no.4
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• pp.152-160
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• 2001

The pretreatment for COD removal of acrylic wastewater and separation characteristics of ultrafiltration hollow fiber type module and reverse osmosis spiral wound type module with the variation of applied pressure and temperature were discussed. Thc optimum washing time of membranes was decided with long team operation and the degree of fouling was discussed with operating time. Permeate flux was decreased rapidly at 14 hrs and that of reverse osmosis membrane was indicated similarly. CaO find sand filter for the first step, neutralization process with treated acrylic wastewater as the second step, UF/RO processes were used as final strep. It was shown treat COD and TDS were below allowable discharge value with the result.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.253-257
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• 2021

This work demonstrates the use of baromembrane method based on reverse osmosis (RO) process. The method is realized on mobile complex, which allows to concentrate and determine ultra-low activity of radionuclides in water cooling ponds of Russian nuclear fuel cycle enterprises. The existence level of radionuclide background creates difficult conditions for identification the contribution of liquid discharges enterprise, as standard monitoring methods have a very high detection level for radionuclides. Traditional methods for determining the background radionuclides concentrations require the selection of at least 500 liters (l) of water, followed by their evaporation to form a dry residue. This procedure with RO membranes requires at least 5 days. It is possible to reduce the time and energy spent on evaporation of hundreds of water liters by pre-concentrating radionuclides in a smaller sample volume with baromembrane method. This approach allows preliminary concentration of water samples from 500 l volume till 20 l volume during several hours. This approach is universal for the concentration of dissolved salts of any heavy metals, other organic compounds and allows the preparation of water countable samples in much shorter time compared to the traditional evaporation method.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.133-143
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• 2021

Background Extensive research has been conducted on islet transplantation as a possible cure for diabetes. Islet transplantation in the liver via the portal vein has shown remarkable results, but numerous other recipient sites are currently being investigated. We aimed to show the effectiveness of using a muscle flap as a recipient site for islet transplantation. Methods Islet cells were harvested from 12 isogenic Lewis rats, and then diabetes was induced in another 12 isogenic Lewis rats by streptozotocin injection. In six rats, 3,000 islets were transplanted into gastrocnemius muscle flaps, and in the other six rats, the same number of islets were transplanted into the gastrocnemius muscle. The transplanted islet cell function between the two groups was compared by means of blood glucose tests, glucose tolerance tests, immunohistochemistry, and real-time reverse transcription polymerase chain reaction. Results In the muscle flap group, blood glucose levels significantly decreased after islet transplantation. Blood glucose levels were significantly different between the two groups at 3 weeks after transplantation. The muscle flap group showed nearly normoglycemic results upon the glucose tolerance test, whereas the muscle group was hyperglycemic. Immunohistochemical evaluation showed positive results against insulin and glucagon in biopsies of both groups, and the islet cell density was higher in the muscle flap group. There were no statistically significant differences between the two groups in real-time reverse transcription polymerase chain reaction results. Conclusions Our results suggest that muscle flaps are promising candidates for islet cell transplantation.

• Korean Journal of Radiology
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• v.21 no.4
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• pp.505-508
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• 2020

The epidemic of 2019 novel coronavirus, later named as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still gradually spreading worldwide. The nucleic acid test or genetic sequencing serves as the gold standard method for confirmation of infection, yet several recent studies have reported false-negative results of real-time reverse-transcriptase polymerase chain reaction (rRT-PCR). Here, we report two representative false-negative cases and discuss the supplementary role of clinical data with rRT-PCR, including laboratory examination results and computed tomography features. Coinfection with SARS-COV-2 and other viruses has been discussed as well.

• Proceedings of the Membrane Society of Korea Conference
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• 2001.05a
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• pp.135-138
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• 2001

Acrylic wastewater flux was discussed using modules of ultrafiltration hollow fiber and reverse osmosis spiral wound. The optimum backflushing times of membranes were decided and the degree of fouling was discussed with operating time. Permeate flux was decreased rapidly at 12hrs. Separation processes with ultrafiltration and reverse osmosis membranes were not suitable to remove COD and TDS. The improvement of pretreatment processes was needed.