• Korean Journal of Animal Reproduction
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• v.25 no.1
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• pp.9-17
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• 2001

To determine the effect of the characteristics of the corpus luteum (CL) and serum metabolites on pregnancy rate following embryo transfer in Hanwoo cow, recipients were synchronized the estrus with CIDR. in vivo or in vitro produced bovine embryos were transferred to synchronized recipients. The characteristics of the CL were checked by rectal palpation and ultrasound. Blood samples were collected from jugular vein at Day 7 and analysed progesterone and serum metabolites. The results obtained from this study were as follows; 1. Total 397 embryos were transferred to recipient and 121 heads out of them were pregnant. The pregnancy rate was 30.5% and slightly differences between farms. 2. There was not significantly different the pregnancy rates between the size of CL and the cavity CL. In the recipients which had more than 2ng/$m\ell$ of serum progesterone level, the pregnancy rates was in higher than others (46.6% vs. 24.4%, 15.0%). 3. The highest pregnancy rate was obtained at 90 to 110mg/㎗ in serum total cholesterol, 14 to 16mg/㎗ in BUN, and 70 to 80mg/㎗ in serum glucose, respectively, and these metabolites in blood could be used as the criteria in the selection of recipient at embryo transfer.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.5
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• pp.485-492
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• 2009

The thermal fatigue crack(TFC) is one of the life-limiting mechanisms at the nuclear power plant operating conditions. In order to evaluate the structural integrity, various non-destructive test methods such as radiographic test, ultrasonic test and eddy current are used in the industrial field. However, these methods have restrictions that defect detection is possible after the crack growth. For this reason, acoustic emission testing(AET) is becoming one of powerful inspection methods, because AET has an advantage that possible to monitor the structure continuously. Generally, every mechanism that affects the integrity of the structure or equipment is a source of acoustic emission signal. Therefore the noise filtering is one of the major works to the almost AET researchers. In this study, acoustic emission signal was collected from the pipes which were in the successive thermal fatigue cycles. The data were filtered based on the results from previous experiments. Through the data analysis, the signal characteristics to distinguish the effective signal from the noises for the TFC were proven as the waveform difference. The experiment results provide preliminary information for the acoustic emission technique to the continuous monitoring of the structure failure detection.

• Membrane Journal
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• v.24 no.2
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• pp.151-157
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• 2014

In this study, the nanofiber composite membrane was prepared by electrospinning method with poly (ancrylonitrile) (PAN) and a dispersed solution of graphene oxide (GO) and $Fe_3O_4$ functionalized graphene oxide (M-GO) in dimethyl formamide (DMF). The pore-diameter of prepared membranes was controlled by change of those layers. It was confirmed with SEM that the nanofiber composite membranes having fiber size of 500 nm were prepared. It was found with Raman spectroscopy and EDS that GO and M-GO were well dispersed on those membranes. Final nanofiber composite membrane showed the similar pore properties ($0.21{\sim}0.24{\mu}m$/pore-size, 40% porosity) with the commercial membrane ($0.27{\mu}m$/pore-size, 55% porosity) and their water-flux results also showed the 200% higher flux than its PAN membrane. From these results, it was expected that the nanofiber composite membrane prepared by electrospinning method could be utilized as a water-treatment membrane.

• 대한공업교육학회지
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• v.34 no.2
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• pp.331-345
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• 2009

In this research Sagnac interferometer three different types of mandrel are suggested and this fiber optic sensor is using in monitoring of electric transformer. Vibration characteristics of those mandrels were analyzed and finally more sensitivity mandrel are suggested. Three different mandrels using in fiber optic sensor are hollow cylinder with outer bump, pure hollow cylinder, hollow cylinder with inner bump. Natural frequencies and mode shapes are investigated using finite element method. Mode shape are considered at the frequency range from 2 kHz to 20 kHz. Fundamental dimensions of the hollow cylinder type's mandrel are 30 mm in outer diameter, 50 mm in length, 1 mm in cylinder thickness, $2mm{\times}2mm$ in bump size. Based on the finite element results, when the outer acoustic frequency is near 11 kHz outer bump type and hollow cylinder can get higher sensitivity. Near 17 kHz outer bump and inner bump mandrel can get higher sensitivity. Near 20 kHz hollow cylinder and inner bump mandrel is useful. This results can be applied to design of fiber optic sensor using in monitoring the electrical transformer. Several MHz of outer acoustic frequency can be easily detected using more sensitive mandrel in pursuing expand this technique.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.334-341
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• 1992

A clinical review of 34 cases of aortic dissection which were admitted to Yeungnam University hospital between March 1983 and April 1992. The results are as follows : 1. The peak incidence was in 5th, 6th decade and male to female ratio was 1.83 : 1. 2. The most common cause of aortic dissection was atherosclerosis and hypertension(79%). 3. The most common presenting symtom was pain(73%), but dyspnea, palpable mass, murmur, shock were also observed. 4. Abnormal electrocardiographic finding was myocardial ischemia in 6 cases, arrythmia in 5 cases, LVH in 5 cases. 5. The X-ray findings showed abnorma aortic conture in 10 cases but normal X-ray finding was observed in 63% of DeBaKey Type III. 6. The most common diagnostic procedure was echocardiogram and abdominal ultrasonography. 7. The mortality of all cases was 20%, operation mortality was 18% but no death of medically treatment in medical indication.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.363-370
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• 2016

The purpose of this study was to determine the effects of speed variations in treadmill training on the thickness of lower extremity muscles. A total of 36 university students were divided into three groups: MVTG (n=12), HVTG (n=12), and ATG (n=12). Subjects in MVTG underwent treadmill training with their own average speed; those in HVTG underwent treadmill training with 130% speed of their own average speed; and those in ATG underwent treadmill training with alteration of speed, between 100% and 130% of their own average speed. Treadmill training was performed for 60 minutes a day, three times per week, for a total of 6 weeks. Ultrasonography was used to compare the muscle thickness between rectus femoris, vastus lateralis, gastrocnemius, and tibialis anterior. The result was as follows: The rectus femoris, vastus lateralis, and gastrocnemius were significantly increased after the training period, and they also were statistically significant in interaction. Moreover, tibialis anterior was also significantly increased. Therefore, compared to the average-speed treadmill training, speed variations had a greater effect on thickening the lower extremity muscles. In the near future, we will conduct a study applying the findings from this study in a rehabilitation program for patients with gait disturbance due to nervous or musculoskeletal system disease.

• Journal of the Korean Ceramic Society
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• v.41 no.5
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• pp.410-416
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• 2004

In this study, we fabricated magnetite coated on a cordierite honeycomb which has complex shape by ultrasound-enhanced ferrite plating. The effects of the plating condition on the formation of the magnetite and its microstructure were investigated. The magnetite coated on the honeycomb became an oxygen-deficient ferrite by H$_2$ gas reduction, then the effects of the molar concentrations of ammonium acetate for $CO_2$ gas decomposition have been studied. As the molar concentration of a pH buffer($CH_3$COONH$_4$, 0.1946∼0.3892 M) solution increased, the average particle size increased about 200∼250 nm. The magnetite coated on the honeycomb was reduced by H$_2$ gas for 2 h at 30$0^{\circ}C$. The inner pressure change in the cell began to occur at 315∼34$0^{\circ}C$. The H$_2$-Reduced magnetite coated on the honeycomb at 35$0^{\circ}C$ contained an oxygen deficient magnetite and $\alpha$-Fe phase. The thermogravimetric analysis with H$_2$ reduction and $CO_2$ decomposition were carried out with the magnetite coated on the honeycomb. A weight loss in process of H$_2$ reduction occurred between 32$0^{\circ}C$ and 34$0^{\circ}C$, while a weight gain was observed during the $CO_2$ decomposition.

• Elastomers and Composites
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• v.47 no.1
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• pp.2-8
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• 2012

In this study, in order to develop renewable bio-based nanocomposites, multi-functional nanocomposites from soybean resins (AESO, MAESO) and nanoclay were prepared. Photoelectrodes for environmental friendly dye-sensitized solar cell using soybean resin were also prepared. Organo-modified nanoclay was directly dispersed in functionalized soybean resins after mixing with styrene as a comonomer and radical initiator was used to copolymerize the nanocomposites. The observed morphology was a mixture of intercalated/exfoliated structure and the physical properties were improved by adding nanoclay. A nanocomposite using MAESO, which added COOH functional group to the soybean resin, showed better dispersibility than AESO composites. Ultrasonic treatment of the nanocomposites also improved the physical properties. Nanoporous $TiO_2$ photoelectrode was also prepared using soybean resins as a binder, after acid-treatment of $TiO_2$ surface using nitric acid. Dye-sensitized solar cells were prepared after adsorbing dye molecules on it. The $TiO_2$ photoelectrode prepared using soybean binder had high current density because of increased surface area by improved dispersibility. The photoelectrochemical properties and conversion efficiency of the solar cell were significantly improved using the soybean binder.

• Journal of Gastric Cancer
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• v.7 no.2
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• pp.97-101
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• 2007

We report our experience with a case of performing laparoscopy-assisted total gastrectomy along with pancreas-preserving splenectomy for treating early gastric cancer. laparoscopy-assisted total gastrectomy was planned for a 62-year-old male patient with a double early gastric cancer located in the upper and lower third of the stomach. Five trocars were placed and we used a harmonic scalpel to dissect the greater curvature. Enlarged splenic hilar lymph node was encountered and they were proved to be metastasis by frozen section biopsy. We then performed total gastrectomy with pancreas-preserving splenectomy for the purpose of completely dissecting the lymph nodes along the splenic artery and splenic hilum. We created a 4 cm sized longitudinal mini-laparotomy below the xiphoid process to remove the specimen, and anastomosis was done via the Roux-en-Y method. The patient was discharged on the 9th postoperative days after an uneventful recovery. Our experience shows that laparoscopy-assisted total gastrectomy with pancreas-preserving splenectomy is a relatively safe procedure for treating upper third early gastric cancer with metastatic splenic hilar lymph nodes.

• Clinical and Experimental Pediatrics
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• v.53 no.2
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• pp.158-162
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• 2010

Purpose : Turner syndrome (TS) is a disorder in which various anomalies can be accompanied, especially cardiovascular, renal, thyroid and auditory problems. The aim of this study is to identify the incidence of these disorders in patients with TS according to karyotype. Methods : We reviewed medical records of 90 patients with TS diagnosed by chromosomal analysis in 4 hospitals from Jan 1998 to Dec 2007. We evaluated these cases by prepared protocol of 4 medical problems.Results : The distribution of karyotype was 45,X (47.8%), mosaic pattern (34.4%) and structural aberration group (17.8%). Renal anomalies, cardiovascular anomalies, thyroid disorders and auditory problems are accompanied in 4.4%, 10.0 %, 11.1% and 5.6%, respectively. 45,X group had renal anomalies (7.0%), cardiovascular anomalies (18.6%), thyroid disorders (9.3%) and auditory problems (11.6%). Mosaic group had renal anomalies (3.2%), thyroid disorders (12.9%), no cardiovascular anomalies and auditory problems. Structural aberration group had cardiovascular anomalies (6.3%), thyroid disorders (12.5%) and no other 2 problems. Patients with 45,X group had a significant higher incidence of cardiovascular anomalies (P =0.025). Conclusion : Our results indicate that there are differences clinically according to karyotype of TS, especially in incidence of cardiovascular anomalies.