• Korean Journal of Animal Reproduction
• /
• v.8 no.1
• /
• pp.16-21
• /
• 1984

This experiment was carried out to compare with the nonsurgical and surgical recovery of fertilized eggs in super-ovulated rabbits. Sixty-four eggs recovered were transferred to twelve synchronized, pseudopregnant rabbits to test the viability of the eggs by surgical transfer. Each group(I, II, III) received a single subcutaneous injection of 5mg PGF2${\alpha}$/kg B.W. at 24(Group I), 48(Group II) and 72 hours (Group III) after mating, respectivity. After the administration of PGF2${\alpha}$, vaginal washings were conducted at 3, 6, 9, 12 and 24 hrs, and frequency of vaginal washing was 5 times for the each group (I, II, III). In Group (IV, V, Ⅵ), the rabbits were killed to recover the fertilized eggs from the genital tract at 24(Group Ⅵ), 48(Group V) and 72 hours (Group Ⅵ) after mating, respectively. The results obtained were as follows: 1. Of the total eggs, 69.3%, 73.4% and 66.9% were recovered for Group I, II and III, respectively from the vagina within 6 hrs after PGF2${\alpha}$ injection and particularly for Group III. 2. The rates of egg recovery versus the number of corpora lutea were 55 (51.6-60%), 35.8 (24-52.6%), 33.4 (25-47%) and 72 (70.7-73.0)%, 60.3 (50-71.4)%, 449(44.4-45.5)% in Group I, II, III and Group IV, V, Ⅵ, respectively. 3. Most of eggs recovered were one-cell stage in Group Iand Group IV. More than one half of the eggs recovered in Group II and V were over eight-cell stage, and most of the eggs were so in Group III and Ⅵ. 4. When sixty-four eggs recovered between 24 to 72 hours after mating were transferred to pseudopregnant rabbits. Three recipients were pregnant, and the rate of pregnancy was 25%.

• Journal of IKEEE
• /
• v.24 no.3
• /
• pp.859-866
• /
• 2020

This paper proposes a 2-ch DC-DC converter with a wide-input voltage range from 2.9V~5.6V for wearable AMOLED displays. For positive voltage V_POS, a boost converter is designed using an over-charged voltage permissible circuit (OPC) which generates a normal output voltage even if over-input voltage is applied, and a SPWM-PWM dual mode with 3-segmented power transistors to improve efficiency at light load. For negative voltage V_NEG, a 0.5x regulated inverting charge pump is designed to increase power efficiency. The proposed DC-DC converter was designed using a 0.18-㎛ BCDMOS process. Simulation results show that the proposed DC-DC converter generates V_POS voltages of 4.6 V and V_NEG voltage of -0.6V~-2.3V for input voltage of 2.9V to 5.6V. In addition, it has power efficiency of 49%~92%, output ripple voltage has less than 20 mV for load current range of 1 mA~70 mA.

• Journal of Food Hygiene and Safety
• /
• v.30 no.3
• /
• pp.281-288
• /
• 2015

Vibrio is a genus of Gram-negative, curved, halophilic, and non-spore-forming bacteria. Some of the Vibrio species, such as V. cholerae and V. parahaemolyticus, often contaminate seafood products and occasionally cause human diseases when the seafood products are ingested. A total of 24 Vibrio strains were isolated from shrimp samples on Thiosulphate citrate bile salt sucrose (TCBS) media in this study. All of the 24 isolates were confirmed to belong to the genus Vibrio by using 16S rRNA gene sequence analyses. Vitek 2 system and species-specific polymerase chain reaction (PCR) methods were used to further identify a total of 29 Vibrio strains at the species level, including the 24 shrimp Vibrio isolates and five Vibrio reference strains. The specificities of the two methods to identify Vibrio strains at the species level were compared in this study. The species-specific PCR method was designed to detect five different Vibrio species, such as Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio alginolyticus, and Vibrio mimicus. From the 24 Vibrio shrimp isolates, the Vitek 2 system method could identify 15 (62.5%) strains as Vibrio species and 7 (29.2%) strains as non-Vibrio species, but could not identify the rest 2 (8.3%) strains. But species-specific PCR method could identify 16 (66.7%) strains as Vibrio species and could not identify the rest 8 (33.3%) strains. Among the 24 Vibrio shrimp strains, these two methods could unanimously identify 7 (7/24, 29.2%) strains (2 V. parahaemolyticus, 4 V. alginolyticus, and 1 V. mimicus). Considering that such different identification results were obtained using the two different methods in this study, identification method for Vibrio species must be carefully chosen.

• Clean Technology
• /
• v.24 no.3
• /
• pp.249-254
• /
• 2018

In order to improve the photo conversion efficiency (${\eta}$) of dye-sensitized solar cells (DSSCs), the electrospun $TiO_2$, $SiO_2$, $ZrO_2$ and $SnO_2$ nanofibers were added into the hydrothermally prepared $TiO_2$ nanoparticles for application to a photoelectrode for DSSCs. The $TiO_2$ nanofiber added photoelectrode exhibited a higher photo current density ($J_{sc}$) compared to the bare $TiO_2$ nanoparticles, which is caused from acceleration of the transfer of excited electron from dye molecule due to the nanofiber structure. The DSSCs with $SiO_2$ nanofibers shows a higher open circuit voltage ($V_{oc}$) of 0.67 V and the highest photo conversion efficiency was found to be 6.24%.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.24 no.10
• /
• pp.78-84
• /
• 2010

This paper describes the safety assessment of power cable splices connecting different sized 6/10[kV] class power cables. To assess the safety, AC withstand voltage tests, partial discharge tests and impulse tests were carried out to the cable splice specimens and thermal rise due to overload and cross section of joint were examined as well. As a result, a breakdown due to the $4.5[U_0](27[kV_{ac}])$ application could not found for 5 minutes. Under $1.73[U_0](10.4[kV_{ac}])$ application, partial discharges of 4~8[pC] were detected. In impulse tests, all the specimens withstood to the standard waveforms of $75[kV_{peak}](1.2{\times}50[{\mu}s])$ without any breakdowns. In addition, the temperature on the splice rose by $3[^{\circ}C]$ when the 200[A] flew through the splice for 20minutes, however the thermal rise of $3[^{\circ}C]$ was considered due to the atmospheric temperature. After all the electrical tests, the cross section of the splice was visually examined. The conditions of the conductors of both $185[mm^2]$ and $240[mm^2]$ were good.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.7 no.4
• /
• pp.281-286
• /
• 2007

In this paper, sub-circuits for 24 GHz phase locked 100ps(PLLs) using $0.5{\mu}m$ SiGe HBT are presented. They are 24 Ghz voltage controlled oscillator(VCO), 24 GHz to 12 GHz regenerative frequency divider(RFD) and 12 GHz to 1.5 GHz static frequency divider. $0.5{\mu}m$ SiGe HBT technology, which offers transistors with 90 GHz fMAX and 3 aluminum metal layers, is employed. The 24 GHz VCO employed series feedback topology for high frequency operation and showed -1.8 to -3.8 dBm output power within tuning range from 23.2 GHz to 26 GHz. The 24 GHz to 12 GHz RFD, based on Gilbert cell mixer, showed 1.2 GHz bandwidth around 24 GHz under 2 dBm input and consumes 44 mA from 3 V power supply including I/O buffers for measurement. ECL based static divider operated up to 12.5 GHz while generating divide by 8 output frequency. The static divider drains 22 mA from 3 V power supply.

• Journal of Environmental Health Sciences
• /
• v.32 no.3
• /
• pp.240-248
• /
• 2006

The purposes of this study were to investigate the symptoms, diseases and deaths of residents living near the municipal solid waste landfill site, and to compare the relative risk ratio of their adverse health effects with control group. In self-evaluation, the scores were especially severe lowest in residents of v2 and v3 villages(which were located about 500 m toward under the landfill site) such as 32.2 and 16.7 for village-environment, 24.8 and 16.0 for management of landfill site, and 23.5 and 16.5 for confidence of environmental policy, respectively. On symptoms, relative risk ratios were also highest as 3.53 and 3.55 for breathing difficulty, and 3.36 and 3.00 for respiratory symptom in v2 and v3 villages, respectively. On morbidity, they were slightly high as much as 1.39 and 1.24 in v5 and v2 villages, respectively. On mortality, relative risk ratios were $1.15{\sim}2.46$ in experimental villages. They were especially high as much as 2.46 in v3 village where located near under the landfill site, and also 2.14 in v5 village where located at area affected with the landfill site, but near the sea. The rate of cancer causing death was average 35.2% of total deaths. It was very highest as much as 61.1 % in v2 village, where was closely located near under the landfill site. Cancers causing death in this village were lung cancer(3 cases), larynx cancer(2 cases), stomach cancer(2 cases), pancreatic cancer(1 case), thryoid cancer(1 case), leukemia(1 case) and other(1 case). Our data, although based on limited number of cases and geographical coverage, suggest that residents living near landfill site have the increasing relative risks of various symptoms and mortality causing cancer. No causal mechanisms are available to explain these findings. But the possibility of a causal association between the increased adverse health effects and the municipal solid waste landfill site cannot be fully excluded.

• Journal of Energy Engineering
• /
• v.24 no.2
• /
• pp.129-143
• /
• 2015

Increasing concerns on climate change and energy security accelerated policies to reduce green-house gas emission, especially from the transportation sector. Electric vehicle (EV) has been on the spotlight to deal with such environmental issue and V2G (Vehicle-to-Grid) technology began to draw attentions as an alternative to reduce ownership costs while contributing to an efficient and decentralized power grid. This study conducts a scenario analysis on total cost of ownership of EV under V2G scheme and compare with non-V2G EV and Internal Combustion Engine (ICE) vehicle. As result, V2G service is expected to provide an annual average profit of $210 to EV users willing to reverse flow its residual power in the battery. The profit from V2G service leaves a margin of $4,530 over operational lifetime, compared with $2,420 cost of charge for non-V2G EV. In summary, total cost of ownership of V2G-capable EV was 6.2% less than non-V2G EV and 10.2% higher than ICE vehicle. The results confirm a comparative economic advantage of operating EV under V2G scheme. Increased number of EVs with V2G service has shown to provide positive effects to power industry for valley filling in load distribution, thus, favorably increasing the overall economic feasibility.

• Journal of Advanced Navigation Technology
• /
• v.24 no.3
• /
• pp.212-217
• /
• 2020

Recently, with the interest in the 4th industrial revolution, the demand for autonomous driving technology is increasing. V2X communication technology is a core technology for autonomous vehicles that exchanges information with objects such as vehicles, infrastructure, networks, and pedestrians through wired and wireless networks. In this paper, we present the results of the hybrid V2X communication system, which is a hybrid design of WAVE and LTE, and the coverage test to confirm the performance of the system. Through coverage measurement, we show that the hybrid V2X communication performance is superior to the existing LTE or WAVE single communication system in communication coverage, so it can be effectively applied to autonomous driving services.

• Journal of the Chungcheong Mathematical Society
• /
• v.24 no.2
• /
• pp.359-370
• /
• 2011

In this work, we obtain new solitary wave solutions for some nonlinear partial differential equations. The Jacobi elliptic function rational expansion method is used to establish new solitary wave solutions for the combined KdV-mKdV and Klein-Gordon equations. The results reveal that Jacobi elliptic function rational expansion method is very effective and powerful tool for solving nonlinear evolution equations arising in mathematical physics.