• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.364-369
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• 2004

The barrier and optical properties of AlO$_{x}$ thin films on polycarbonate deposited by Reactive Ion Beam Sputtering (RIBS) were investigated at different oxygen partial pressure. We measured the deposition rate of AlO$_{x}$ thin films. As the oxygen partial pres-sure increased, the deposition rate increased then decreased. The changes of deposition rate are associated with the properties of deposited films. The properties of deposited AlO$_{x}$ thin films were studied using X-ray Photoelectron Spectroscopy (XPS), Scan-ning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). Optimum deposition parameters were found for fabricat-ing aluminum oxide thin films with high optical transparency for visible light and low Oxygen Transmission Rate (OTR). The optical transmittance of AlO$_{x}$ thin film deposited on polycarbonate (PC) showed the same value of bare PC.bare PC.

• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.699-706
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• 2016

Partial discharges (PD) lead to the degradation of high voltage cables and accessories. PD activities occur due to the existence of impurities, voids, contaminants, defects and protrusions during the manufacture and installation of power cables. Commonly, insulation failures occur at cable joints and terminations, caused by inhomogeneous electric field distributions. In this work, a blend of natural rubber (NR) and linear low density polyethylene (LLDPE) was investigated, and the optimal formulation of the blend that could resist PD was discussed. The experiments were conducted under a constant high voltage stress test of 6.5 kV AC and the magnitude of partial discharge activities was recorded using the CIGRE method II. Pattern analysis of PD signals was performed along with the interpretation of morphological changes. The results showed that the addition of 10 wt% of NR and 5 wt% of Alumina Trihydrate (ATH) provided promising results in resisting PD activities. However, as the NR content increased, more micropores existed, thus resulting in increased PD activities within the samples.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.494-494
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• 2000

This paper demonstrates that the largest Lyapunov exponent $\lambda$ of recurrent neural networks can be controlled by a gradient method. The method minimizes a square error $e_{\lambda}=(\lambda-\lambda^{obj})^2$ where $\lambda^{obj}$ is desired exponent. The $\lambda$ can be given as a function of the network parameters P such as connection weights and thresholds of neurons' activation. Then changes of parameters to minimize the error are given by calculating their gradients $\partial\lambda/\partialP$. In a previous paper, we derived a control method of $\lambda$via a direct calculation of $\partial\lambda/\partialP$ with a gradient collection through time. This method however is computationally expensive for large-scale recurrent networks and the control is unstable for recurrent networks with chaotic dynamics. Our new method proposed in this paper is based on a stochastic relation between the complexity $\lambda$ and parameters P of the networks configuration under a restriction. Then the new method allows us to approximate the gradient collection in a fashion without time evolution. This approximation requires only $O(N^2)$ run time while our previous method needs $O(N^{5}T)$ run time for networks with N neurons and T evolution. Simulation results show that the new method can realize a "stable" control for larege-scale networks with chaotic dynamics.

• Composites Research
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• v.12 no.2
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• pp.26-35
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• 1999

This paper presents the vibration damping characteristic of a single lap joint beam with partial dampers analyzed using the model strain energy method and the harmonic response analysis which were based on a finite element model. The two finite element analysis methods exhibited very similar results of the resonant frequency and system loss factor which were comparable to those by the theoretical analysis. Effects of the location of partial dampers and elastic moduli and thickness of their layers on the system loss factor were studied. The damping effects due to changes of modules and loss factor of the viscoelastic layer in lap joint and partial dampers were also studied. Consequently, the geometrical and material conditions at maximizing the system loss factor were suggested.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.31-36
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• 2000

180g of fermented soy paste and 150g of red pepper paste were packaged in glass jars of 232 mL with different conditions of active packaging and then stored at $13^{\circ}C$ for about 170 and 128 days, respectively. During the storage, package atmosphere, surface color, pH, acidity and microbial flora were monitored to see the effect of packaging conditions. Test packaging conditions include package equipped with $Ca(OH)_2\;as\;CO_2$ absorber, package with pinhole and closed control one. Closed control packages of soypaste and red pepper paste showed the increased $CO_2$ partial pressure, the decreased $O_2$ partial pressure and the constant $N_2$ partial pressure to produce high pressure buildup with storage. The paste packages with $Ca(OH)_2$ maintained relatively low $CO_2$ partial pressure and thus the package pressure close to normal atmospheric pressure for initial storage period of 70 days. The packages with air pinhole channel had the partial pressures of $O_2\;and\;N_2$ decreased with storage time, while $CO_2$ partial pressure first increased to a maximum and then slowly decreased thereafter Without any pressure increase the packages with pinhole gave the lowest quality changes possibly due to the effect of package atmosphere, but it had problem of mold contamination and growth for soy paste after 120 days. There were no difference in microbial flora between the packages after about 70 day storage.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.3
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• pp.160-165
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• 2012

Objectives: This study evaluated the clinical results of partial sublingual glandectomy accompanying the excision of ranula as new treatment modality. Materials and Methods: A total of 43 patients who were treated between 1999 and 2007 for oral or plunging ranula were reviewed. All patients were treated surgically by various methods with a total of 55 different procedures performed. Ten cases of partial sublingual glandectomy with excision of the ranula were conducted. All excised specimens were examined. We compared the clinical outcomes resulting from each treatment method. Results: The recurrence rates for marsupialization, excision of ranula, marsupialization with gauze packing, total excision of sublingual gland and ranula, and partial sublingual glandectomy with excision of ranula were 50%, 25%, 25%, 0% and 10%, respectively. Of the 10 patients treated by partial sublingual glandectomy with ranula excision, only one experienced recurrence (10%), i.e., plunging ranula. None of the ranulas contained an epithelial lining, and the excised portion of the feeding sublingual glands showed degenerative changes. Conclusion: In removal of ranulas, we found that excision of the attached sublingual gland, which removed the feeding portion and degenerative acinar cells, yielded good outcomes. Thus, as a new conservative method for treatment, we recommend partial sublingual glandectomy to accompany excision of the ranula.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.274-282
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• 2012

The object of this study was to assess the efficacy of Polycan from Aureobasidium pullulans SM-2001, which is composed mostly of beta-1,3-1,6-glucan, on osteoarthritis (OA)-induced by anterior cruciate ligament transection and partial medial meniscectomy (ACLT&PMM). Three different dosages of Polycan (85, 42.5, and 21.25 mg/kg) were orally administered once a day for 84 days to male rats a week after ACLT&PMM surgery. Changes in the circumference and maximum extension angle of each knee, and in cartilage histopathology were assessed using Mankin scores 12 weeks after Polycan administration. In addition, cartilage proliferation was evaluated using bromodeoxyuridine (BrdU). As the result of ACLT&PMM, classic OA was induced with increases in maximum extension angles, edematous knees changes, and capsule thickness, as well as decreases in chondrocyte proliferation, cartilages degenerative changes, and loss of articular cartilage. However, these changes (except for capsule thickness) were markedly inhibited in all Polycan- and diclofenac sodium-treated groups compared with OA control. Although diclofenac sodium did not influence BrdU uptake, BrdU-immunoreactive cells were increased with all dosages of Polycan, which means that Polycan treatment induced proliferation of chondrocytes in the surface articular cartilage of the tibia and femur. The results obtained in this study suggest that 84 days of continuous oral treatment of three different dosages of Polycan led to lesser degrees of articular stiffness and histological cartilage damage compared with OA controls 91 days after OA inducement, suggesting that the optimal Polycan dosage to treat OA is 42.5 mg/kg based on the present study.

• Applied Microscopy
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• v.17 no.1
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• pp.115-130
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• 1987

The present experiment was performed to investigate the acute effects of cadmium on ultrastructural and biochemical changes in mouse kidney and compare these changes with liver damage. Mouse were injected with cadmium chloride at a dose of 5 mg/kg body weight. After treatment, mouse were sacrificed at time intervals of 6, 12, 24 and 48 hours. It was observed that ultrastructural changes in mouse kidney were composed of swelling of mitochondria, dilation in endoplasmic reticulum, wrinkling at basal infolded membrane, formation of autophagosome and partial loss of microvilli in brush. border, and that ultrastructural changes in liver were mitochondrial change, dilation and deterioration of rough endoplasmic reticulum and proliferation of smooth endoplasmic reticulum. Biochemical effects of cadmium were more severe on liver than kidney. Therefore, acutely injected cadmium caused not only liver damage, but also kidney damage.

• Journal of Photoscience
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• v.9 no.2
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• pp.326-328
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• 2002

In many plant cells, the positions of chloroplasts change in response to changes in light conditions. In the epidermal cells of the aquatic angiosperm Vallisneria gigantea, the avoidance response of chloroplasts is induced specifically by irradiation with blue light of high intensity. Possible roles of actin cytoskeleton in the blue-light-induced avoidance response of chloroplasts were investigated by partial irradiation and phalloidin staining. We showed that the blue-light-dependent redistribution of chloroplasts was induced only in the limited area, where exposed to blue light, even in individual cells. In addition. in the exposed area, the configuration of actin filaments strikingly changed compared with that before the irradiation. Short and thick bundles of actin filaments surrounding the chloroplasts changed to much longer and thinner bundles with a more stretched array. In contrast, in the unexposed area, neither the distribution of chloroplasts nor the configuration of actin filaments exhibited any changes. Cytochalasin D and latrunculin B inhibited the avoidance response of chloroplasts concomitantly with the fragmentation of actin filaments. These results indicate that the reorganization of actin filaments plays a crucial role in the induction of avoidance response of chloroplasts.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.936-945
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• 1998

This study was performed to investigate the best surgical technique for normal stifle mobility by comparison with clinical signs and histopathological changes of articular cartilage after femoral trochleoplasty, trochlear chondroplasty and trochlear wedge recession. Twelve small mixed dogs who had grade I or II medial patellar luxation were used. The days that the dog had partial and full weight bearing were checked and histopathological changes 49 and 90 days after surgery were observed. The dogs had partial weight bearing in 3~6 days postoperatively and full weight bearing in 20~24 days. After femoral trochlepoplasty, the articular surface was irregular and rough, but smooth after trochlear chondroplasty and trochlear wedge recession. Histopathologic examination performed on the 49th and 90th days after femoral trochleoplasty revealed that articular surface was occupied by fibrocartilage but the hyaline cartilages are preserved after trochlear chondroplasty and trochlear wedge recession. In trochlear wedge recession, the wedges of all cases were firmly attached to underlying subchondral bone which were indicating complete healing. The results of this study suggested that the trochlear wedge recession was the best chondroplasty for correcting patellar luxation.