• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.89-95
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• 2000

This study was to establish an effective dilution technique in a vitrification of bovine blastocysts for the field trial. For vitrification, blastocysts were exposed in glycerol (G) and ethylene glycol (EG) mixture in m-DPBS supplemented with 10% FBS. Blastocysts were first exposed to 10% (v/v) G for 5 min, and subsequently were transferred to 10% G plus 20% EG (v/v) for 5 min. Finally, embryos were transferred to 25% G plus 25% EG (v/v) for 30 see and were placed in nitrogen vapor for 3 min, and then were plunged into L$N_2$. At thawing, the straw containing blastocysts was placed in air for 10 sec, and then plunged into a water bath at $25^{\circ}C$ until all ice had disappeared. They were placed in $25^{\circ}C$ and 36$^{\circ}C$ water according to treatment group for different time. Also, in vitro survival was assessed by the re-expansion and hatched rates at 24 hand 48 h postwarming, respectively. The results obtained in these experiments were summarized as follows; 1) In the survival rates of vitrified bovine blastocysts according to different dilution time at thawing, the data of 1 min group (86.6, 56.6%) were higher than those of other treatment groups (2 min; 93.5, 35.4%, 2.5 min; 76.9, 30.7%, 3 min; 88.8, 36.1% and 3.5 min; 83.7, 8.1%). 2) When the in vitro survival of vitrified groups according to different developmental stage was examined at 48 h after thawing using 1 min dilution method, the hatching rates of fast developed embryos (expanded blastocyst: 81.3%: early hatching blastocyst: 86.2%) were higher than that of delayed developed one (early blastocyst: 46.6%). 3) In addition, when the in vitro survival of vitrified groups according to different embryo age was compared, the hatched rates at 48 h after thawing of Day 7 (66.6%) and Day 8 embryos (60.0%) were significantly higher than that of Day 9 embryos (22.7%) (P＜0.05). These results demonstrate that vitrified bovine IVM/IVF/IVC blastocysts can be successfully survived in vitro using one-step dilution (1 min) method.

• Journal of Korean Society of Forest Science
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• v.98 no.4
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• pp.451-457
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• 2009

This study was conducted to evaluate the felling productivity by chain saw in thinning operation of Korean pine (Pinus koraiensis) stands. Time study data were collected from 4 thinning site in Korean pine stands. This study derived a regression model to estimate the average felling cycle time for evaluating the productivity in felling, which was used to analyze the felling productivity by thinning period. In the study sites, the average felling cycle time per a tree was 463 sec/cycle and the productivity was $2.26m^3/hr$. Thinning period in Korean pine is divided into three groups by producing purposes; small-diameter log, medium-diameter log, and large-diameter log. And analyzed working time and productivity from thinning period fixed by producing purposes. For the small-diameter log producing purpose estimated to be thinning period operated once when the mean DBH was 16 cm and its productivity was $8.94m^3/man{\cdot}day$. For the medium-diameter and large-diameter log producing purposes, thinning period was twice and three times when the mean DBH of the 1st and 2nd thinning period was 16 cm and 21 cm, and its productivity was $9.06m^3/man{\cdot}day$ and $10.86m^3/man{\cdot}day$. The 30 cm in DBH and $15.12m^3/man{\cdot}day$ in productivity was operated 3rd thinning for the large-diameter log producing purposes.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.325-334
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• 2008

Statement of problem & Purpose: The purpose of this study was to investigate the effect of a mouth guard material properties on the skull and brain when they were under impact loads on mandible. Material and methods: Two customized mouth protectors having different material propeerst ieach other were made for a female Korean who had no history of brain trauma, no cerebral diseases, nomal occlusion and natural dentition. The 3D finite element model of human skull and brain scanned by means of computed tomography was constructed. The FEM model of head was composed of 407,825 elements and 82,138 nodes, including skull, brain, maxilla, mandible, articular disc, teeth and mouth guard. The stress concentrations on maxillary teeth, maxilla and skull with two mouth guards were evaluated under oblique impact load of 800N onto mandibular 3 loading points for 0.1sec. And the brain relative displacement was compared in two different mouth guard materials under same condition. Result and Conclusion: The results were as follows; 1. In comparison of von Mises stress on maxillary teeth, a soft mouth guard material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 2. In comparison of von Mises stress on maxilla and skull, A soft mouth protector material had significantly lower stress values on measuring point than a hard mouth protector materials (P < .05). 3. For impact loads on mandible, there were more stress concentrated area on maxilla and skull with hard mouth guard than soft with mouth protector. 4. For impact loads on mandible, brain relative displacement had little relation with mouth guard material properties. In results of this study, soft mouth guard materials were superior to hard mouth guard materials for mandible impact loads for prevention of sports injuries. Although the results of this study were not enough to figure out the roles of needed mouth guard material properties for a human head, we got some knowledge of the pattern about stress concentration and distribution on maxilla and skull for impact loads with soft or hard mouth protector. More studies are needed to substantiate the relationship between the mouth guard materials and sports injuries.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.91-104
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• 1996

The viability loss or death of weed seeds buried in soil can be induced by infrared irradiation which has good penetration in moist soil. By using this principle of pre-emergence soil-treatment, the study was carried out to obtain basic information needed to develop the effective weed control method for the production of less polluted agricultural products. An apparatus for irradiating infrared was constructed by using ceramic material with high emissivity. The LPG was used as fuel for producing infrared by heating ceramic material. The soil heated in this study was loam with four levels of moisture contents (0.6, 5.7, 10.7, 15.1 % wb). The temperature distribution was measured at various soil depths when soil with different moisture content was irradiated with infrared for three different times (30, 60, 90 sec). The soil depths with duration time of minimum 3 minutes over $80^{\circ}C$, temperature inducing viability loss of weed seeds, were investigated. When the moisture content of soil was 0.6 and 5.7 % wb, the soil depths which can induce viability loss of weed seeds was greatly increased with increasing irradiation time. However, any depths of soil tested in this study was not reached to the temperature of $80^{\circ}C$ when 30 seconds of irradiation time was applied on soil with moisture content of 10.7 or 15.1 % wb. Generally, the soil depth needed for viability loss of weed seeds was decreased with increasing moisture content of soil. Also, longer irradiation time was required to induce viability loss of weed seeds with increasing moisture content of soil.

• The Korean Journal of Physiology
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• v.23 no.2
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• pp.237-252
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• 1989

Effect of a $Na^+$ gradient on $Ca^{2+}$ uptake was studied in isolated sarcolemmal vesicles of cat ileal longitudinal muscle. $Ca^{2+}$ uptake was markedly stimulated in the presence of an outwardly directed $Na^+$ gradient. External $Na^+$, monensin and A23187 abolished the $Na^+-dependent$ $Ca^{2+}$ uptake. Monovalent cations such as $K^+$, $Li^+$, $Rb^+$, $Cs^+$ and choline could not substitute for $Na^+$ in enhancement of $Ca^{2+}$ uptake. Divalent cations such as $Ba^{2+}$, $Sr^{2+}$, $Mn^{2+}$ and $Cd^{2+}$ but not $Mg^{2+}$ inhibited the $Na^+-dependent$ $Ca^{2+}$ uptake. Increase in external pH in the range of 6.0 to 8.0 stimulated the $Na^+-dependent$ $Ca^{2+}$ uptake. Amiloride inhibited the $Na^+-dependent$ $Ca^{2+}$ uptake at concentrations above 0.5 mM, whereas diltiazem or vanadate did not. The apparent Km of the $Na^+-dependent$ $Ca^{2+}$ uptake for $Ca^{2+}$ was 18.2 ${\mu}M$ and apparent Vmax was 689.7 pmole/mg protein/5 sec. Kinetic analysis of the $Na^+-dependent$ $Ca^{2+}$ uptake showed a noncompetitive interaction between internal $Na^+$ and external $Ca^{2+}$. The dependence of $Ca^{2+}$ uptake on internal $Na^+$ showed sigmoidal kinetics and Hill coefficient for internal $Na^+$ was 2.52. Inside positive membrane potential generated by imposing an inwardly directed $K^+$ gradient and valinomycin significantly stimulated the $Na^+-dependent$ $Ca^{2+}$ uptake. These results indicate that a $Na^+-Ca^{2+}$ exchange system exists in the sarcolemmal membranes isolated from cat ileal longitudinal muscle and it might operate as an electrogenic process.

• Journal of Sasang Constitutional Medicine
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• v.18 no.2
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• pp.68-82
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• 2006

1. Objectives and Methods The purpose of this study was to objectify the diagnosis of Sasang constitution. It was analyzed the adult men and women's [i] sound into 23 factors with PSSC-2004. The study was conducted by subjects inputting 2.5-3 sec of [i] of 586 adult men and women's voices to PSSC-2004. The statistical analysis are applied to three groups : total group, male group, female group. The group of total 586 was composed with 155 Soyangin, 230 Taeumin and 201 Soeumin. The male group was composed with 61 Soyangin, 127 Taeumin and 87 Soeumin. The female group was composed with 94 Soyangin, 103 Taeumin and 114 Soeumin. 2. Results (1) In total group, the Soyangin's code3 was significantly low compared with the others(P=0.011). In total group, the Taeumin's code2 and the Soyangin's code1 were significantly high compared with the others(p=0.007)(P=0.030). (2) In total group, the Soyangin's peak, 50 up in peak and under 3 in peak were significantly low compared with the others(P=0.003) (P=0.005)(P=0.023). (3) In total group, the Taeumin's rank7, rank8, rank9 and rank10 were significantly high compared with the others (P=0.013)(P=0.015) (P=0.016)(P=0.003). (4) In male group, the Soeumin's code3 was significantly high compared with the others(P=0.002). (5) In male group, the Soeumin's peak sum was significantly high compared with the others(P=0.009). It was significant for distinction between Soeumin and Soyangin at the result of post mortem. In male group, the Soeumin's 50 up in peak, 50 down in peak were significantly high compared with the others(P=0.049)(p=0.037). In male group, the Soeumin's under 3 in peak was significantly high compared with the others(P=0.016). It was significant for distinction between Soeumin and Soyangin at the result of post mortem. (6) In male group, the Soeumin's rank 2, rank 3 and rank 4 were significantly low compared with the others(P=0.011) (0.011)(0.024). (7) In female group, the Taeumin's code2 was significantly high compared with the others(P=0.023). In female group, the Soyangin's code1 was significantly low compared with the others (P=0.046). In female group, Soyangin's code-1 was significantly high compared with the others(P=0.024). It was significant for distinction between Taeumin and Soyangin at the result of post mortem. (8) In female group, the Taeumin's peak sum was significantly high compared with the others(P=0.024). It was significant for distinction between Taeumin and Soyangin at the result of post mortem. In female group, the Taeumin's 50 up in peak was significantly high compared with the others(P=0.012). (9) In female group, the Taeumin's rank 7, rank 8, rank 9 and rank 10 were significantly high compared with the others (P=0.009) (P=0.013)(P=0.016)(P=0.023). 3. Conclusion From above result, there is the possibility of efficiency standardguide for constitutional diagnosis by analyzation of the voices.

• Journal of Veterinary Clinics
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• v.30 no.6
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• pp.442-448
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• 2013

The aim of the present study was to develop glycerol-free TRIS extender using glucose for dog sperm cryopreservation. We determined the appropriate concentration of glucose in glycerol-free TRIS and the exposure time in glycerol-free TRIS containing 0.3 M glucose at $4^{\circ}C$. Ejaculates of six dog sperm were cooled in glycerol-free TRIS through $4^{\circ}C$ for 100 min, cooled at $4^{\circ}C$ in TRIS with different glucose concentrations 0 M, 0.04 M, 0.1 M, 0.2 M and 0.3 M, respectively for 30 min followed by cryopreservation. After thawing at $37^{\circ}C$ for 25 sec, membrane and acrosome integrities of dog sperm were evaluated. In addition, the effect of exposure time (10, 30, 50 and 70 min) of sperm to glycerol-free TRIS containing 0.3 M glucose at $4^{\circ}C$ on progressive motility, viability, and DNA integrity following sperm cryopreservation was studied. Membrane integrity and acrosome integrity were assessed by 6-carboxyfluoresceindiacetate (6-CFDA)/propidium iodide (PI) fluorescent staining and Pisum sativum agglutinin conjugated to fluorescein isothiocyanate, respectively. DNA integrity was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling, using flow cytometry. Sperm frozen in glycerol-free TRIS supplemented with 0.2 M or 0.3 M glucose have an intact plasma membrane (CFDA+/PI-) after cryopreservation than sperm frozen in the extenders with lower glucose concentrations (p<0.05). Acrosome integrity was significantly higher in the 0.3 M group than less than 0.1 M groups (p<0.05). The sperm DNA fragmentation index did not differ according to exposure time, although progressive motility was significantly higher in the 50 min exposure group than the other groups (p<0.05). These results indicate that cryopreservation of dog sperm is feasible and yields more motile sperm following freezing and thawing in glycerol-free TRIS containing 0.3 M glucose with the exposure time for 50 min at $4^{\circ}C$.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.237-243
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• 2013

Pesticides were sprayed on perilla leaf and leafy lettuce in a greenhouse and the reduction rate of pesticide residues on each vegetable by washing were tested. The reduction rate of pesticide residues by washing for 30 sec~3 min on perilla leaf were 3~63% in tap water, 2~58% in salt water, 6~74% in green tea water, and 8~86% in detergent solution. The detergent solution only showed significant difference in reduction rates compared to the tab water washing. Considering reduction effects of the washing duration, it was showed that the reduction rates were a pattern of inclining as the duration of washing process increased, but there was no significant difference in the reduction rates except the reduction rates between washing in the detergent solution for 1 min and 3 min. Comparing washing in flowing tab water and in stagnant tab water with leafy lettuce, the reduction rate by one time washing were 8~68% in flowing tab water and 7~64% in stagnant tab water. The water and the time used in this experiment were 17.5 L, 2.9 min with flowing tab water and 4 L, 1 min with stagnant tab water. The reduction rate by 3 times washing in stagnant tab water were 16.5~76.6%, and the water and the time used were 12 L, 3 min. Therefore, when the water and the time used to wash vegetables were considered, washing two or three times in stagnant tab water could be more effective than washing one time in flowing tab water.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.513-523
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• 2001

This study was conducted to investigate influences of solifluction and sediment runoff on the stream water qualities during the spring season. The study sites were four points in the northeastern area of the Bukhansan National Park. And, field surveys were carried out in the spring of 1999, 2000 and 2001. The results of this study were summarized as follows; During the investigation period, the amounts of sediment caused by solifluction on stream side slopes in the downstream were 1.3~1.7 times as large as those in the upstream. The pH of sediment caused by solifluction was a potential influence on the pH of stream water. Amounts of dissolved $Cl^-$, $NO_3{^-}$ and $SO{_4}^{2-}$ in stream water were proportion to the average amounts of $Cl^-$, $NO_3{^-}$ and $SO{_4}^{2-}$ in the sediment caused by solifluction. In the spring, the average pH of stream water was lower than the first class of the river water quality standard because of increasing chemical concentration as well as the contents of anions($Cl^-$, $NO_3{^-}$ and $SO{_4}^{2-}$) in the spring season. Also, the average electrical conductivity of water in downstream was about 2.3-3.3 times higher than that in upstream. The amounts of anions($Cl^-$, $NO_3{^-}$ and $SO{_4}^{2-}$) of water in downstream were about 1.2~7.4, 1.1~3.9, 1.1~1.4 times higher than those in upstream, respectively. Therefore, these results showed that the water quality of downstream was worse than that of upstream. As a result of regression analyses, the linear and exponential equation of pH and water quantity was pH = 1.7926 ${\times}$ stream water quantity + 5.9577($R^2=0.46$), and those of electrical conductivity and water quantity was $EC=34.417e^{3.6334{\times}\text{stream water quantity}(m^3/sec)}$ ($R^2=0.44$).

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.11
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• pp.140-149
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• 1996

Cursive characters are written on an economical principle to reduce the motion of a pen in the limit of distinction between characters. That is, the pen is not lifted up to move for writing a next stroke, the pen is not moved at all, or connected two strokes chance their shapes to a similar and simple shape which is easy to be written. For these reasons, strokes and korean alphabets are not only easy to be changed, but also difficult to be splitted. In this paper, we propose a curvature stroke modeling method for splitting and matching by using a structural primitive. A curvature stroke is defined as a substroke which does not change its curvanture. Input strokes handwritten in a cursive style are splitted into a sequence of curvature strokes by segmenting the points which change the direction of rotation, which occur a sudden change of direction, and which occur an excessive rotation Each reference of korean alphabets is handwritten in a printed style and is saved as a sequence of curvature strikes which is generated by splitting process. And merging process is used to generate various sequences of curvature strikes for matching. Here, it is also considered that imaginary strokes can be written or omitted. By using a curvature stroke as a unit of recognition, redundant splitting points in input characters are effectively reduced and exact matching is possible by generating a reference curvature stroke, which consists of the parts of adjacent two korean alphasbets, even when the connecting points between korean alphabets are not splitted. The results showed 83.6% as recognition rate of the first candidate and 0.99sec./character (CPU clock:66MHz) as processing time.