• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.40-40
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• 2001

Heat stress to bovine oocytes and embryos has suggested a potential role of retardation of their development. Limited study has reported on the effect of heat shock on sperm before using it for IVF. Caudal epididymal sperm cultured in 42$^{\circ}C$ incubator for 0.5, 1 and 2 h compared on sperm viability and oocyte development after its use for IVF to those of control. Oocytes were matured for 22 h and then inseminated with treated or control sperm for 16 h. Embryos were cultured in CRlaa medium, transferred to TCM199＋10% FBS on day 4, and maintained on day 9. A higher proportion (84.1%, 0.5 h; 72%, 1 h: 65%, 2 h) in treated sperm was observed dead and abnormal pattern as 100% of consider as control. In control the rates of cleavage and development into blastocyst were 76% and 22%, respectively, and did not differ the rates between 1 h and 2 h of culture. Significant differences were appeared in the rates between treated for an hour and control (32% and 5% vs. 54% and 10%, respectively). Moreover increased time of culture is more retardation to be cleaved the oocytes. However, the rates of blastocyst from cleaved embryos in treated group similar to control (25% vs. 29%, respectively). The reason for this remains unclear, but male sperm, from preliminary experiment(data un-shown) for sexing of resulting embryos, would be more fragility on heat stress.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.576-585
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• 2020

This study quantitatively investigated the increase in ballasting time through numerical calculations when an ultraviolet (UV) ballast water management system (BWMS) is installed on an existing vessel. The calculation results indicate that the ballasting time of a gas carrier having 55,000 dead weight tonnage was 2.152 hours without installation of the UV BWMS and implementation of a flow control function. Ballasting time increased by 14.2% after installing the UV BWMS, and it increased by 20.4% with both its installation and implementation of a flow control function. If actual conditions are taken into account, ballasting time after installing the UV BWMS is estimated to increase by at least 30% compared with current ballasting time. Therefore, when concerned parties select a UV type BWMS, it is advisable for them to minimize ship operation losses from an increase in ballasting time by considering the capacity of the actual ballast pumps on board and the flow energy loss of the UV BWMS. Additionally, it is recommended that a BWMS with larger capacity, larger pipes, and pipes with inside coatings be used to minimize the increase in ballasting time after installation of the BWMS.

• Journal of the Korea Society for Simulation
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• v.25 no.4
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• pp.21-30
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• 2016

Recently manufacturing companies have used PLC control programs popularly for their automated production systems. Since the life cycle of production process is not so long, the change of the production lines occur frequently. Most of changes happen with modification of the position information and control process of the equipment. PLC control program is also modified based on the fundamental process. Therefore, to verify new PLC program by configuring virtual space according to real environment is needed. In this paper we show a logical modeling method, based on Timed-FSA useful for sequence control and dead-lock prevention. There is a problem wasting user's labor and time when defining a variety of states in a device. To overcome this problem, we propose an extended I-O model based on existing methods by adding a token concept of Petri Nets. Also we will show the usability of the extended I-O modeling through user study.

• Journal of Veterinary Science
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• v.23 no.5
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• pp.78.1-78.13
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• 2022

Background: Florfenicol might be ineffective for treating Staphylococcus aureus small colony variants (SCVs) mastitis. Objectives: In this study, florfenicol-loaded chitosan (CS)-sodium tripolyphosphate (TPP) composite nanogels were prepared to allow targeted delivery to SCV infected sites. Methods: The formulation screening, the characteristics, in vitro release, antibacterial activity, therapeutic efficacy, and biosafety of the florfenicol composite nanogels were studied. Results: The optimized formulation was obtained when the CS and TPP were 10 and 5 mg/mL, respectively. The encapsulation efficiency, loading capacity, size, polydispersity index, and zeta potential of the optimized florfenicol composite nanogels were 87.3% ± 2.7%, 5.8% ± 1.4%, 280.3 ± 1.5 nm, 0.15 ± 0.03, and 36.3 ± 1.4 mv, respectively. Optical and scanning electron microscopy showed that spherical particles with a relatively uniform distribution and drugs might be incorporated in cross-linked polymeric networks. The in vitro release study showed that the florfenicol composite nanogels exhibited a biphasic pattern with the sustained release of 72.2% ± 1.8% at 48 h in pH 5.5 phosphate-buffered saline. The minimal inhibitory concentrations of commercial florfenicol solution and florfenicol composite nanogels against SCVs were 1 and 0.25 ㎍/mL, respectively. The time-killing curves and live-dead bacterial staining showed that the florfenicol composite nanogels were concentration-dependent. Furthermore, the florfenicol composite nanogels displayed good therapeutic efficacy against SCVs mastitis. Biological safety studies showed that the florfenicol composite nanogels might be a biocompatible preparation because of their non-toxic effects on the renal tissue and liver. Conclusions: Florfenicol composite nanogels might improve the treatment of SCV infections.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.6919-6922
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• 2015

Background: The treatment selection for the oral squamous cell carcinoma remains controversial. Radiation therapy or surgical excision of the lesion can be applied as the sole treatment or it can be used in combination with other treatment modalities. Radiotherapy is considered to be the safest of all the treatment modalities and can be used in several situations for oral and oropharyngeal cancers. The aim of this study was to evaluate the survival outcome differences in patients treated with radical and palliative radiotherapy as the primary treatment modality. Materials and Methods: The study included a total of 47 patients with oral cancer reporting to our hospital between years 2009 to 2010. The age group for the selected patients was more than 65 years, treated with radical and palliative radiotherapy with no prior surgical interventions. Patients were evaluated till Dec 2013 for overall survival time. Results: Twenty nine patients were treated with radical radiotherapy as main stay of treatment, out of which 21 died during the follow up time with median survival of $352{\pm}281.7$ days with 8 patients alive. All the 16 patients were dead who received palliative radiotherapy with a median survival time of $112{\pm}144.0$ days. Conclusions: This retrospective study showed improved overall survival time, loco regional control rates and reduced morbidity in patients treated with radical radiotherapy when compared to patients treated with palliative radiotherapy.

• Archives of Plastic Surgery
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• v.34 no.5
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• pp.611-616
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• 2007

Purpose: The latissimus dorsi muscle flap is a versatile flap used in a variety of reconstructive procedures. The most common complication of LD muscle flap is donor site seroma, reported to occur in 20 to 79 percent of cases. The formation of dead space under the flap is intimately associated with seroma formation. The authors think that the use of progressive tension suture at closing donor site can decrease the formation of dead space and ultimately reduce the incidence of donor site seroma. Methods: A retrospective review was performed with 38 patients who underwent latissimus dorsi muscle harvest for breast reconstruction from March 2003 to September 2004. Progressive tension sutures were used during donor site closure in 22 patients. This group was compared with controls group(16 patients) who underwent latissimus dorsi muscle harvest without using this technique. Operation time, length of hospital stay, period of drainage, complication, and satisfaction about postoperative scar of donor site were examined. Results: The average length of hospital stay was 10.2 days and 12.7 days, and the mean duration of drainage were 7.3 days and 11.7 days in each progressive suture group and control group. These results were statistically significant (p<0.05). In the 22 patients who underwent progressive tension suture, none had seroma, hematoma or skin necrosis. In control group(16 patients), there happened one seroma formation and one partial skin necrosis. These complications were healed by aspiration of seroma and wound revision. The patients' satisfaction was not statistically significant, but the higher points were given by the patients who underwent progressive tension suture. Conclusion: This technique, progressive tension suture, is an effective method to reduce or eliminate donor site seroma, which is the most common complication associated with latissimus dorsi muscle harvest.

• Water Engineering Research
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• v.3 no.1
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• pp.57-62
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• 2002

This research is intended to integrate long-term operation rules and real time operation policy for conservation & flood control in a reservoir. The familiar Yield model has been modified and used to provide long-term rule curves. The model employs linear programming technique under given physical conditions, i.e., total capacity, dead storage, spillways, outlet capacity and their respective elevations to find required and desired minimum storage fur different demands. To investigate the system behavior resulting from the above-mentioned operating policy, i.e., the rule curves, the simulation model was used. Results of the simulation model show that the results of the optimization model are indeed valid. After confirmation of the above mentioned rule curves by the simulation models, gate operation procedure was merged with the long term operation rules to determine the optimum reservoir operating policy. In the gate operation procedure, operating policy in downstream flood plain, i.e., determination of damaging and non-damaging discharges in flood plain, peak floods, which could be routed by reservoir, are determined. Also outflow hydrograph and variations of water surface levels for two known hydrographs are determined. To examine efficiency of the above-mentioned models and their ability in determining the optimum operation policy, Esteghlal reservoir in Iran was analyzed as a case study. A numerical model fur the solution of two-dimensional dam break problems using fractional step method is developed on unstructured grid. The model is based on second-order Weighted Averaged Flux(WAF) scheme with HLLC approximate Riemann solver. To control the nonphysical oscillations associated with second-order accuracy, TVD scheme with SUPERBEE limiter is used. The developed model is verified by comparing the computational solutions with analytic solutions in idealized test cases. Very good agreements have been achieved in the verifications.

• Korean Journal of Veterinary Pathology
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• v.5 no.1
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• pp.9-16
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• 2001

To investigate the effects of safflower seed supplementation diet on the hepatic injury of rats administered with carbon tetrachloride (CCI$_4$), histopathological changes were assessed following acute and chronic administration in rats. In acute cases, all rats in group fed with 10% safflower seed supplementation diet survived despite the administration of lethal doses of $CCl_4$. However, most rats in group fed with control diet died. The hepatic injuries of survived rats, in the histopathological findings, were mild compared to those of dead rats. In the chronic cases, livers of group 2 fed with control diet were more progressive in fatty changes and centrilobular necrosis than those of group 3 fed with 20%safflower seed diet. However, after six weeks, livers of group 2 and 3 showed severe necrosis and mild fibrosis at the same time. Group 5 fed with 10% safflower seed supplementation diet and water containing 0.05% phenobarbital sodium showed mild fatty changes and necrosis compared with group 4 fed with control diet and water containing 0.05% phenobarbital sodium at sixth week. At 8 to 10 wee71s after the administration of $CCl_4$, severe fibrosis. fatty changes and marked necrosis were observed in group 4, but hepatic injuries were less severe in group 5. The present results suggested that safflower seed has some protective effect in hepatic lesions and consequently delay the progression of hepatic fibrosis.

• Smart Structures and Systems
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• v.23 no.5
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• pp.449-466
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• 2019

Cable-stayed bridges are attractive due to their beauty, reducing material consumption, less harm to the environment and so on, in comparison with other kinds of bridges. As a massive structure with long period and low damping (0.3 to 2%) under many dynamic loads, these bridges are susceptible to fatigue, serviceability disorder, damage or even collapse. Tuned Mass Damper (TMD) is a suitable controlling system to reduce the vibrations and prevent the threats in such bridges. In this paper, Multi Tuned Mass Damper (MTMD) system is added to the Ahvaz cable stayed Bridge in Iran, to reduce its seismic vibrations. First, the bridge is modeled in SAP2000 followed with result verification. Dead and live loads and the moving loads have been assigned to the bridge. Then the finite element model is developed in OpenSees, with the goal of running a nonlinear time-history analysis. Three far-field and three near-field earthquake records are imposed to the model after scaling to the PGA of 0.25 g, 0.4 g, 0.55 g and 0.7 g. Two MTMD systems, passive and active, with the number of TMDs from 1 to 8, are placed in specific points of the main span of bridge, adding a total mass ratio of 1 to 10% to the bridge. The parameters of the TMDs are optimized using Genetic Algorithm (GA). Also, the optimum force for active control is achieved by Fuzzy Logic Control (FLC). The results showed that the maximum displacement of the center of the bridge main span reduced 33% and 48% respectively by adding passive and active MTMD systems. The RMS of displacement reduced 37% and 47%, the velocity 36% and 42% and also the base shear in pylons, 27% and 47%, respectively by adding passive and active systems, in the best cases.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.337-340
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• 2007

In the dissertation, a power conversion system for fuel cell is composed of a PWM inverter with LC filter in order to convert fuel cell voltage to a single phase 220[V], In addition, new insulated DC-DC converters are proposed in order that fuel cell voltage is boosted to 380[V]. In this paper, it requires smaller components than existing converters, which makes easy control. The proposed DC-DC converter controls output power by the adjustment of phase-shift width using switch S5 and S6 in the secondary switch, which provides 93-97[%] efficiency in the wide range of output voltage. Fuel cell simulator is implemented to show similar output characteristics to actual fuel cell. Appropriate dead time td enables soft switching to the range where the peak value of excitation current in a high frequency transformer is in accordance with current in the primary circuit. Moreover, appropriate setting to serial inductance La reduces communication loss arisen at light-load generator and serge voltage arisen at a secondary switch and serial diode. Finally, TMS320C31 board and EPLD using PWM switching technique to act a single phase full-bridge inverter which is planed to make alternating current suitable for household.