• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.23-28
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• 2003

The present study was undertaken to investigate the effects of PVP concentration and exposure temperature to vitrification solution on the post-thaw survival, in vitro maturation and development of immature bovine oocytes (germinal vesicle stage). The vitrification solution (VS) consisted of 40% ethylene glycol (EG)+0.5 M sucrose (S)+10% FBS. PVP was added to VS: 0%, 5% or 10%. The cumulus-oocyte complexes (COCs) were diluted in VS as one step, after 2 min the COCs were loaded in straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were plunged into $30^{\circ}C$ water bath for 10s. After thawing, the oocytes were diluted in 0.5 M (in DPBS with 10% FBS) sucrose solution for 5 min. The survival rate (FDA-test and trypan blue) of immature bovine oocytes was measured. The survival rate was higher in 5% PVP (91.5%) than in 0% (64.2%) or in 10% PVP (79.7%). The proportion of metaphase II formation was 69.35% in control (no vitrified COCs), 9.3% in 40% EG+0.5 M S+0% PVP and 21.05% in 40% EG+0.5 M S+5% PVP (p<0.05). The effect of room temperature ($25^{\circ}C$ for 10 min) and cold temperature ($4^{\circ}C$ for 10 min) on COCs were determined in this study. After IVF, the cleavage and blastocysts rate of oocytes exposed to room temperature and cold temperature in VS+5% PVP was significantly different (2 cell: 63.20% vs 37.97%, blastocysts: 18.40% vs 2.53%). The cleavage rates of frozen-thawed oocytes were 20.53% with PVP and 22.13% without PVP (p>0.05). Two out of 151 oocytes (1.32%) developed to blastocyst stage after frozen-thawed with 5% PVP (p>0.05). Development of oocytes after frozen-thawing to the 2 cell were not significantly affected with or without PVP following IVF. However, the vitrification of immature bovine oocytes with PVP maintained the ability to develop to the blastocyst stage after IVM-IVF and IVC, while no blastocysts were obtained from oocytes vitrified without PVP. These results suggested that PVP has a protective role for vitrification of immature bovine oocytes as far as survival is concerned, however, the protection was not sufficient enough to support blastocyst formation.

• Journal of Acupuncture Research
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• v.22 no.6
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• pp.27-36
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• 2005

Introduction : The aim of the study is to investigate the suppressive action of electroacupuncture on cold alloynia development in the rat model of neuopathic pain. Methods : To produce neuropathic pain, the right superior caudal trunk was resected $1{\sim}2\;mm$ between S1 and S2 spinal nerves. The rats were divided into control and four electroacupuncture groups: Two electroacupuncture groups were given 2 Hz or 100 Hz electroacupuncture for 20 minutes everyday after the sacral nerve injury. Other two electroacupuncture groups were given 2 Hz or 100 Hz electroacupuncture for 20 minutes just one session at one hour after the sacral nerve injury. The right point of Joksamni (ST36) was applied for electroacupuncture. The control group was induced neuropathic pain without electroacupuncture. The cold allodynia was assessed by immersing the tail in $4^{\circ}C$ water. The latency to an abrupt tail movement after rat tail immersion was measured with a cut-off time of 15 sec at 4th, 7th and 14th day after the sacral nerve injury. Results : The results were as follows; 1. At 4th experimental day, there were no significant differences between 2 Hz or 100 Hz electroacupuncture groups and the control group. 2. At 7th experimental day, everyday 2 Hz or 100 Hz electroacupuncture groups showed significant differences compared with the control group. But There were no significant differences between 2 Hz and 100 Hz electroacupuncture groups. 3. At 14th experimental day, everyday 2 Hz electroacupuncture group showed significant differences compared with the control group. But everyday 100 Hz electroacupuncture group showed no significant difference compared with the control group and everyday 2 Hz electroacupuncture group. 4. There were no significant differences between the control and 2 Hz or 100 Hz electroacupuncture groups which were done just one session at one hour after the surgery. 5. Everyday 2 Hz electroacupuncture group showed significant differences in the one session of the 100 Hz electroacupuncture group. Conclusion : Everyday 2 Hz electroacupuncture exerts a suppressive action on cold allodynia development in the rat model of neuropathic pain.

• Journal of the Korea Concrete Institute
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• v.16 no.1 s.79
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• pp.1-9
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• 2004

This paper represents the permeability of chloride ions and the corrosion performance in the concrete blended with granulate blast furnace slag exposed to chloride environment. An ordinary cement (type I ) and sulfate resisting cement(type V) were used for the experiment. The two cements were combined with $0\%$, $25 \%$, $40\%$, and $55\%$ of the granulated blast furnace slag. The accelerated permeability tests of chloride ions were performed in accordance with ASTM C1202, and the accelerated corrosion tests of steel were carried out by using the method of immersion/drying cycles. After water curing 28 days, 56 days and 91 days, these tests were conducted until 30 cycles. In every cycle, test specimens were wetted in $3\%$ NaCl solution for three days and dried again in $60^{\circ}C$ air for four days. As an experimental results, the diffusion coefficient of chloride ions of the ordinary cement Concrete Combined granulated blast furnace slag was much lower than that of non granulated blast furnace slag concrete. Moreover, the diffusion coefficient of chloride ions of sulfate resisting cement concrete was higher than that of ordinary cement concrete. On the basis of the results of accelerated corrosion tests, corrosion resistance of the concrete mixed with granulated blast furnace slag shows good to corrosion resistance, however, the concrete with sulfate resisting cement shows bad to corrosion resistance.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.490-496
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• 2005

This study was conducted to clarify the effects of chemicals and physical treatment on the split of flower stalk and the vase life of Lycoris squamigera and Lycoris radiata. There was no split of flower stalk for the Lycoris squamigera and the Lycoris radiata after the harvest of flowers and the immersion in 4 mM STA solution for 30 minutes. It was effective for the vase life of Lycoris squamigera that cut flower was pre-treated in 4 mM STS solution for 30 minutes and immersed in $5\~10\%$ sucrose + 150 ppm 8-HQS +4 ppm Rox preservative solution. The optimum periods of hot water treatments for the prevention of flower stalk split and the elongation of vase life for the cut flowers were 15 to 25 seconds for the Lycoris squamigera and 5 to 10 seconds for Lycoris radiata. Burning the cut parts of flower stalk for 10 to 30 seconds was effective for the prevention of flower stalk split and the elongation of vase life for the Lycoris squamigera, and 10 to 15 seconds for the Lycoris radiata. The vase lifes of Lycoris squamigera and Lycoris radiata were elongated when flower stalk was cut by an incline of 45 degrees compared with the horizontal cut. And Banding the flower stalks of cut flowers was effective for the prevention of flower stalk split and the elongation of vase life for the Lycoris squamigera and the Lycoris radiata.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.2
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• pp.95-102
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• 2005

There are many tube and pipeline in nuclear power plant under high temperature and high pressure. Erosion and corrosion defects were expected on these tube and pipe-line by environmental and mechanical factors. These erosion and corrosion defects ran be evaluated by ultrasonic technique. In these study, Scanning Laser Source(SLS) technique was applied to detect defect and construct image. This technique also makes detection possible on rough and curved surfaces such as tube and pipe-line by scanning. Conventional ultrasonic scanning technique requires immersion of specimen or water jet for transferring ultrasonic wave between transducer and specimen. However, this SLS technique does not need contacting and couplant to generate surface wave and to get flaw images. Therefore, this SLS technique has several advantages, for complicated production inspection, non-contact, remote from specimen, and high resolution. In this study, SLS images were obtained with various conditions of generation laser ultrasound and receiving in order to enhance detectability of flaws on the tube. Stress corrosion cracks were produced on tube and images of stress corrosion cracks were constructed by using SLS technique.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.5
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• pp.262-267
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• 2009

Superhydrophobic $TiO_2$ thin films were successfully fabricated on a glass substrate by wet process. Layer-by-layer (LBL) deposition and liquid phase deposition (LPD) methods were used to fabricate the thin films of micro-nano complex structure with a high roughness. To fabricate superhydrophobic $TiO_2$ thin films, the (PAH/PAA) thin films were assembled on a glass substrate by LBL method and then $TiO_2$ nanoparticles were deposited on the surface of (PAH/PAA) thin film by LPD method, Subsequently, hydrophobic treatment using fluoroalkyltrimethoxysilane (FAS) was carried out on the surface of prepared $TiO_2$ thin films. The $TiO_2$ thin film fabricated with 45 minutes immersion time on $(PAH/PAA)_{10}$ showed the RMS roughness of 65.6nm, water contact angel of $155^{\circ}$ and high transmittance of above 80% (>650nm in wavelength) after the hydrophobic treatment. The Surface morphologies, optical properties and contact angel of prepared thin films with different experimental conditions were measured by field emission scanning electron microscope (FE-SEM), atomic force microscope (AFM), UV-Vis spectrophotometer and contact angle meter.

• Membrane Journal
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• v.24 no.1
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• pp.10-19
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• 2014

Porous flat sheet membranes for separators in Zn air batteries were prepared with polyethersulfone (PES) solutions by immersion precipitation phase inversion method. PES/polyvinylpyrrolidone(PVP)/N-methylpyrrolidone(NMP) mixtures were used for casting solutions and water was used for coagulant. With the separators, Zn air batteries were fabricated. The separators were characterized by means of stress-strain test, impedance test and SEM. The Zn air batteries were tested by current interrupt method (CIM) and galvanostatic discharge method. The tensile strength increased with increasing PES content in the casting solution while the ionic conductivity decreased. On the other hand, the ionic conductivity increased while the tensile strength decreased with increasing PVP content. The effect of ionic conductivity trend of the separator in the Zn air battery was confirmed through current interrupt method and galvanostatic discharge method experiments. The battery with the separator from casting solution with higher PES content showed higher IR drop and lower discharge capacity. And the battery with the separator from casting solution with higher PVP content showed lower IR drop and higher discharge capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.261-268
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• 2018

The use of electric cable was limited due to the installation time and large space as the increase of power demand and load quantity in side line. In order to solve these problems, the application of busway system which can supply the large current was increasing. But it was lack of methods of performance tests to evaluate the reliability and results of test for busway system. In this paper, we presented items to evaluate the reliability test for epoxy coated busway system with reference to IEC 61349-6. In addition, we proposed items to evaluate the reliability and long term life cycle test for the epoxy coated busway system. The combined acceleration deterioration test that reflects actual conditions of the survey as much as possible was conducted considering both thermal and electrical stresses. The deterioration condition was selected to satisfy fifty years life expectation and the insulation performance verification test of the busway system confirmed the long term life prediction. Furthermore, as test items for reliability assessment of compliance with the environment for the use of temperature, humidity and load current where busway system was installed, thermal overload test, water immersion test, cold shock temperature test and thermal cycle test were performed. And we examined changes in characteristics and abnormality after tests. From results, the test items presented to evaluate performance and reliability of the epoxy insulated busway system were confirmed to be appropriate in this paper, and the performance of the product was also confirmed to be excellent for reliability tests.

• Fisheries and Aquatic Sciences
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• v.21 no.9
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• pp.26.1-26.8
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• 2018

Inclusion effect of soybean meal (SBM) and fermented SBM (FSM) in extruded pellet for juvenile abalone (Haliotis discus) was compared in abalone farm. Dietary inclusion effect of the combined macroalgae (MA) (Undaria pinnatifida and Hizikia fusiforme) and a single Saccharina japonica on abalone was also compared. Three thousand six hundred juvenile abalone were purchased from a private hatchery and acclimated to the experimental conditions for 2 weeks. Six 5-ton flow-through raceway tanks were used, and abalone were randomly distributed into tanks (n = 600 per tank). Three experimental diets were prepared in duplicate. Fish meal, FSM, corn gluten meal, and shrimp meal and wheat flour and dextrin were used as the protein and carbohydrate sources, respectively, in the FSM diet. MA was also included in the FSM diet. FSM and MA in the FSM diet were substituted with SBM at the expense of wheat flour and S. japonica, referred to as the SBM and SJ diets. The experimental diets were pelletized by an extruded pelleter. Water stability of nutrients in the experimental diets was monitored at 12, 24, and 48 h after seawater immersion. The experimental diets were fed to abalone once a day to satiation with a little leftover for 120 days. The retained crude protein and lipid and ash content of the extruded pellets were changed over all period of time. Weight gain and specific growth rate (SGR) of abalone fed the SBM diet were greater than those of abalone fed the FSM and SJ diets. Weight gain and SGR of abalone fed the SJ diet were also greater than those of abalone fed the FSM diet. The longest shell length, widest shell width, highest shell height, and greatest soft body weight were obtained in abalone fed the SBM diet, followed by the SJ and FSM diets. Proximates of the soft body of abalone were not different among the experimental diets. In conclusion, SBM was a superior protein source to FSM in extruded pellet for growth performance of abalone. Dietary inclusion of a single S. japonica was superior to the combined inclusion of U. pinnatifida and H. fusiforme in the production of abalone.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.4
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• pp.423-429
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• 2017

As invigoration plan of the marine tourism, Busan City has the plan to operate the cruise ship inside of the harbor, but the area has narrow water way with heavy traffic. As a result it is requested to evaluate the safety for the preparation of actual navigation. In this study, the Ship Handling Simulation (SHS) Assessment was conducted, which is regulated by the Maritime Traffic Safety Audit Scheme (MTSAS) in compliance with the Marine Safety Law and the Maritime Traffic Risk Assessment System based on the Electronic Chart Display and Information System (ECDIS). The proximity assessment, control assessment and subjective assessment were implemented, which is enacted by the Marine Safety Law by using the SHS. In the case of proximity assessment, the probability of trespass was not analyzed. As the control assessment, the swept path was measured at 11.7 m and 11.5 m for port entry and port departure respectively, which exceeded the width of the model vessel, 10.4 m over; it was considered as a marginal factor. As a result of the subjective evaluation of the navigator, there would be no difficulty on ship maneuvering by paying particular attention to the mooring vessel nearby the Busan Bridge and Yeongdo Bridge as well as the coming vessel from the invisible sea area when the vessel is entering and departing the port. The Marine Traffic Risk Assessment System analyzed as [Cautious] level until the vessel passed the Busan bridge and the curved area at 5 kts and it became to [Dangerous] level from where it left 75 m to the Busan Bridge. When the vessel passed the Busan Bridge and the curved area at 10 kts and entered the narrow area, it indicated the [Dangerous] level and became to [Very dangerous] level from where it left 410 m to the Busan bridge. In conclusion, the vessel should maintain at the speed of 5 kts to reduce the risk when it passes this area.