• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.286-291
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• 1998

SAR has provided weather independent images on land and sea surface, which can be used for extracting various useful informations. Recently attempts to estimate wind field parameters from SAR images over the oceans have been made by various groups over the world. Although scatterometer loaded in ERS-1 and ERS-2 observes the global wind vector field at spatial resolution of 50 Km with accuracies of $\pm$2m/s in speed, the spatial resolution may not be good enough for applications in coastal regions. It is weil known the sea surface roughness is closely correlated to the wind field, but the wind retrieval algorithms from SAR images are yet in developing stage. Since the radar backscattering properties of the SAR images are principally the same as that of scatterometer, some previous studies conducted by other groups report the success in mesoscale coastal wind field retrievals using ERS SAR images. We have tested SWA (SAR Wind Algorithm) and CMOD4 model for estimation of wind speed using an ERS-1 SAR image acquired near Cheju Island, Korea, in October 11, 1994. The precise estimation of sigma nought and the direction of wind are required for applying the CMOD4 model to estimate wind speed. The wind speed in the test sub-image is estimated to be about 10.5m/s, which relatively well agrees to the observed wind speed about 9.0m/s at Seoguipo station. The wind speed estimation through the SWA is slightly higher than that of CMOD4 model. The sea surface condition may be favorable to SWA on the specific date. Since the CMOD4 model requires either wind direction or wind speed to retrieve the wind field, we should estimate the wind speed first using other algorithm including SWA. So far, it is not conclusive if the SWA can be used to provide input wind speed data for CMOD4 model or not. Since it is only initial stage of implementing the wind field retrieval algorithms and no in-situ observed data is currently avaliable, we are not able to evaluate the accuracy of the results at the moment. Therefore verification studies should be followed in the future to extract reliable wind field information in the coastal region using ERS SAR images.

• Journal of Chest Surgery
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• 제25권1호
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• pp.1-16
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• 1992

The quantitatively measured local myocardial perfusion rates with microspheres are used as an objective indicator of even distribution of cardioplegic solution, and the efficacy of the retrograde right atrial route of cardioplegia is evaluated in hearts with various levels of coronary arterial obstruction. After initial antegrade cardioplegia under the median sternotomy and aortic cannulation, 60 hearts from anesthetized New Zealand white rabbits are divided in random order as normal group [ligated left main coronary artery ; MA, MR] and diagonal group [ligated proximal diagonal artery ; LA, LR]. Half of each group [N=10] are perfused with antegrade cardioplegia[A] under the pressure of 100 cmH2O and the other half with retrograde right atrial route[R] under the pressure of 60 cmH2O[St. Thomas cardioplegic solution mixed with measured amount of microspheres]. The myocardium is subdivided into segments as A[atria], RV[right ventricle]. S[septum], LV[normally perfused left ventricular free wall], ROI[ischemic myocardium of left ventricular free wall]. LV and RQI are further divided into N[subendocardium] and P[subepicardium]. The resulting local myocardial perfusion rates and N /P of each group are compared with Wilcoxon rank sum test. The weight of the hearts is 5.94$\pm$0.66g, and there are no statistically significant dif-ferences[p>0.05, ANOVA] between six compared group. The mean flow rate[F: ml /g / min] of MR group is comparable with MA group[p>0.05], but in N and L group, there are significantly depressed F with right atrial route of cardioplegia, which means elevated perfusion resistance with this route. In spite of no significant differences in delivered doses of microsphere[DEL] between compared groups[p>0.05, ANOVA], there are significantly depressed REC and NF in hearts with right atrial cardioplegia which suggests increased requirement of cardioplegic solution with this route. The interventricular septum shows poor perfusion with right atrial route of cardioplegia without obstruction of supplying coronary arteries. But, with obstruction of coronary artery supplying septum as in M group, the flow rate is superior with right atrial route of infusion. The left ventricular free wall perfusion rates of every RQI with R route are superior to that of A route[p<0.05]. But, in LV segments, there are unfavorable effects of right atrial cardioplegia in L group, although the subendocardial perfusion is well maintained in N group. The LV free wall of left main group shows depressed perfusion rates with antegrade route as compared with RQI segments of diagonal group. But, by contraries, there are increased perfusion rates and superior N /P ratio with retrograde right atrial route. It implies more effective perfusion with right atrial route of cardioplegia in more proximal coronary arterial obstruction[i.e., M group as compared with L group]. As a conclusion, all region of ischemia have superior perfusion rates with right atrial car-dioplegia as compared with antegrade route, and especially excellent results can be obtained in hearts with more proximal obstruction of coronary arteries which would otherwise result in more severe ischemic damage. But, the depressed perfusion rates of the segments with normal coronary artery in hearts with coronary arterial obstruction may be a problem of concern with right atrial cardioplegia and needs solution.

• Journal of Chest Surgery
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• 제47권1호
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• pp.6-12
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• 2014

Background: Although a residual intimal tear may contribute to the dilatation of the descending aorta following surgical repair of acute type I aortic dissection (AD), its causal relationship has not been elucidated by clinical data due to the limited resolution of imaging modalities. Methods: This study enrolled 41 patients (age, $55.2{\pm}11.9$ years) who were evaluated with dual-source computed tomography (CT) imaging of the whole aorta in the setting of the surgical repair of acute type I AD. Logistic regression models were used to determine the predictors of a composite of the aortic aneurysm formation (diameter >55 mm) and rapid aortic expansion (>5 mm/yr). Results: On initial CT, a distal re-entry tear was identified in 9 patients. Two patients failed to achieve proximal tear exclusion by the surgery. Serial follow-up CT evaluations (median, 24.6 months; range, 6.0 to 67.2 months) revealed that 14 patients showed rapid expansion of the descending aorta or aortic aneurysm formation. A multivariate analysis revealed that the residual intimal tear (odds ratio [OR], 4.31; 95% confidence interval [CI], 1.02 to 19.31) and the patent false lumen in the early postoperative setting (OR, 4.64; 95% CI, 0.99 to 43.61) were predictive of the composite endpoint. Conclusion: The presence of a residual intimal tear following surgery for acute type I AD adversely influenced the expansion of the descending aorta.

• Journal of Biosystems Engineering
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• 제38권3호
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• pp.208-214
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• 2013

Purpose: Performances of a tractor diesel engine fueled by three different animal fats biodiesels were evaluated comparing with light oil tractor in terms of power, fuel consumption rate, exhaust gases, particulate matter amount and field work capacity. Methods: Animal fats based on pig biodiesel were manufactured manually and tested for its engine performance in the tractor diesel engine and fuel adoptability in the field works. Four different fuels, three different content of biodiesel (BD20, BD50, BD100) and light oil, were prepared and tested in the four strokes diesel engine. Power output, fuel consumption rate and exhaust gases of the four fuels in the diesel engine were compared and discussed. Results: Power output of light oil engine was the greatest showing 5.3% difference between light oil and BD100, but 0.37% better power than BD20 engine power. Less exhaust gases of $CO_2$, CO, $NO_X$ and THC were produced from animal fats biodiesel than light oil, which confirmed that biodiesel is environmental friendly fuel. For fuel adoptability in the tractor, biodiesel engine tractor showed its fuel competitiveness comparing with light oil for tractor works in the faddy field. Conclusions: With four different fuel types of animal-fats biodiesel, performances of a four cylinder diesel engine for tractor were evaluated in terms of power, exhaust gases, particulate matters (PM) and field work capacity. No significant differences observed in the engine performances including power output and exhaust gases emission rate. No significant power difference observed between the various fuels including light oil on the engine running, however, amounts of noxious exhaust gases including $CO_2$ and $NO_X$ decreased as biodiesel content increased in the fuels. Field performances of animal-fats biodiesel tractor were investigated by conducting plowing and rotary operation in the field. Tilling and rotary performance of light oil tractor and BD20 tractor in the field were compared, in which about 10% travelling speed difference on both operations were monitored that showed light oil tractor was superior to BD20 tractor by 10%. Animal-fats can be an alternative fuel source replacing light oil for agricultural machinery and an environmental friendly fuel to nature.

• 한국가축번식학회지
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• 제4권1호
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• pp.35-45
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• 1980

The purpose of this experiment was to investigate the effects of castration and administration of testosterone propionate(TP) on the development of the thyroid, adrenal glands and the testis in immature male rats, 25 days immatured, weighing 64.1${\pm}$2g, were divided into two groups of control and castrated, each sub-divided into 30 rats again, treated and untreated with TP respectivity. Each rat was given 20$m\ell$ of TP subcutaneously at two weeks interval. Six rats among each group were randomly sacrificed at 7, 21, 35, 49, and 63 days after treatment, of which their thyroid, adrenal glands and testis were collected for cytometric observation. The results obtained were as follows. 1. The size of the follicle of thyroid glands had a tendency to increase proportionally to the treatment period in every group. However, in castration group, the follicular size of the untreated with TP were significantly increased from 49 days (p<0.05) after treatment than that of the treated with TP, while in control group, the treated with TP were not increased during the treatment period. Regarding the height of the follicular epithelial cell in thyroid gland, the treated with TP had a tendency to increase than the untreated with TP in both castration and control group. 2. Regarding the size of the follicle of thyroid gland in relation with the increment period, the untreated with TP in control group were slightly increased from 49 days after treatment, but the treated with TP were not changed significantly. Castration group had a tendency to increase significantly than the control group, especially the untreated with TP in castration group were significantly increased. 3. As for the change of the relative height of thyroidal follicular epithelial cell in relation with the increment of treatment period, the untreated, A and C group, in both castration and control group were increased at 35 days 63 days after treatment while the treated, B and D group had tendency to increase from 21 days after treatment. 4. Regarding the thickness fo adrenal cortex, the castration group had a tendency to increase than the control group until 21 days after treatment. But, at 35 days, the change of the thickness was reversed; Mean while at 49 days and 63 days, especially C group in castration were significantly increased than any other groups although there were no significant differences among the every group during the whole treatment period. Regarding the thickness of adrenal cortex in relation with the increment of treatment period, A, B and C group had a tendency to increase until 21 days after treatment. After that period, there was no significant increment in all groups. Especially, in D group, there were no significant changes from 7 days to 63 days after treatment. 5. As for the tickness of adrenal medulla, there were no significant changes in every group of castration and TP treatment, except that the castration group had a tendency to increase continually than the control throughout the whole treament period. 6. In terms of the number, diameter and thickness of seminiferous tubule in testis of control group, the treated group with TP were distinctly reduced than those of the untreated group from 49 days after treatment respectively.

• 자원환경지질
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• 제30권4호
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• pp.279-289
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• 1997

Dark to pale green-colored, Cr-bearing sericites from hydrothermal alteration zone of the Narim gold deposit were investigated mineralogically and geochemically. The alteration zone is composed mineralogically of quartz, carbonate minerals and green sericite with minor amounts of chlorite, barite and sulfide minerals (pyrite, sphalerite, galena). The zone is enriched in As (967 to 1520 ppm), Cu (31 to 289 ppm), Ni (1027 to 1205 ppm), Pb (0.20 to 1.24 wt.%) and Zn (1.03 to 1.07 wt. %) compared with fresh rocks such as granitic gneiss, porphyritic biotite granite and basic dyke. The Cr, probably the chromophore element, is highly enriched in the alteration zone (1140 to 1500 ppm), host granitic gneiss (1200 ppm) and porphyritic biotite granite (1200 ppm). Occurrence and grain size of sericite are diverse, but most of the Cr-bearing sericites (150 to $200{\mu}m$ long and 20 to $30{\mu}m$ wide) occur along the boundaries between ore veins and host rocks (especially basic dyke and granitic gneiss). X-ray diffraction data of the sericite show its monoclinic form with unit-cell parameters of $a=5.202{\AA}$, $b=8.994{\AA}$, $c=20.103{\AA}$, ${\beta}=95.746^{\circ}$ and $V=935.83{\AA}^3$, which are similar with the normal 2M1-type muscovite. Representative chemical formula of the sericite is ($K_{1.54}Ca_{0.03}Na_{0.01}$)($Al_{3.42}Mg_{0.38}Cr_{0.14}Fe_{0.06}V_{0.02}$)($Si_{6.69}Al_{1.31}$)$O_{20}(OH)_4$. The Cr content increases with decrease of the octahedral Al content, and ranges from 0.36 to 2.58 wt.%. DTA and TG curves of the sericite show endothermic peaks at $342^{\circ}$ to $510^{\circ}$, $716^{\circ}$ to $853^{\circ}$ and $1021^{\circ}C$, which are due to the expulsion of hydroxyl group. The total weight loss by heating is measured to be about 8.8 wt. %, especially at $730^{\circ}C$. Infrared absorption experiments of the sericite show broad absorption band due to the O-H bond stretching vibration near the $3625cm^{-1}$, coupled with the 825 and $750cm^{-1}$ doublet. The vibration bands related with the H-O-Al and Si-O-Al bonds occur at $1030cm^{-1}$ and 500 to $700cm^{-1}$, respectively. Based on paragonite content of the sericite, the formation temperature of the Narim gold deposit is calculated to be $220{\pm}10^{\circ}C$.

• Applied Microscopy
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• 제27권3호
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• pp.265-279
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• 1997

This study aims to demonstrate the effect of chitosan, one of the natural chelator, on the ultrastructural changes in the mouse liver caused by cadmium. A total of 60 healthy ICR that weighted 30 gm $({\pm}2gm)$ was used for experiment. The experimental group was divided into three groups; group A, B, and C. The group A and B administrated cadmium (4.0 mg/kg) to the intraperitoneal after pretreated with chitosan (0.5% solution) for 30 and 7 days, respectively. Each group was observed at 12, 24, 48, 72 hours and one week after injected cadmium. The results were as follows: 1. Group A The nuclear membrane and the chromatin were normal shapes at overall the time. The inner and outer membranes of the mitochondria damaged a little but almost normal in shapes. And electron-density showed slightly compacted. some enlarged rER (rough endoplasmic reticulum) showed at 12 hours. At 48 hours, typical lamellae of the rER were reformed, and a lot of transvesicles observed around them. To 48 hours, sER (smooth endoplasmic reticulum) was slightly dilated. From 72 hours, sER rehalizated in normal shape. 2. Group B Nuclear membranes were rounded-shape and chromatin showed evenly. To 72 hours, a lot of mitochondria observed around rER and development of cristae showed weakly. But at one week, cristae were clear and electron-density of matrix showed high. At 72 hours lamellae of rER showed some broken, but were reformed at one week. Also at one week, glycogen granules evenly showed over cytoplasm. 3. Group C At 12 hours, Nucleus showed the condensation of nuclear membrane and clear condensation at 24 hours. However, nuclear membrane had a slightly rounded-shape from 72 hours. From 12 hours to the one week, mitochondria showed the dilation of inner cavity and weak development of cristae. Also electron-density of matrix was a little low. Occasionally, destruction of inner and outer membrane observed at one week. The dilation of cisternae and destruction of lamellae of rER showed from 12 to 48 hours. From 72 hours, rER showed slightly dilated only. And lamella observed at one week. In sER, dilation of inner cavity was observed during whole period. These results suggest that chitosan attenuates the toxic effect of the cadmium in the mouse liver.

• 한국수산과학회지
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• 제47권6호
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• pp.719-725
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• 2014

This study was investigated for the purpose of obtaining basic data for application to the canning process of salt-fermented anchovy Engraulis japonica fillet using tomato paste. The salt fermented anchovy fillet was prepared by fermenting anchovy fillet with salt 15% at $5^{\circ}C$ for 15 days and then cold air drying the salt-fermented anchovy fillet for 1 h at $16{\pm}1^{\circ}C$. The dried salt-fermented anchovy fillet 85 g was filled with 60 g of tomato paste sauce (tomato paste 42%, gum guar 1.0%, salt 2.0%, starch syrup 2.0%, cooking wine 1%, water 52%) and seamed by vacuum seamer in 301-3 can, then sterilized at Fo 9 and 11 min in a steam system retort at $121^{\circ}C$, respectively. The factors such as chemical composition, pH, total volatile basic nitrogen (TVB-N), amino-N, color value (L, a, b), texture profile, thiobarbituric acid (TBA) value, sensory evaluation and viable bacterial count of the canned salt-fermented anchovy fillet were measured. Texture value of the product sterilized at Fo 11 min was higher than at Fo 9 min condition. In both sterilized cans, the viable bacterial counts were not detected. There was no remarkable difference in physicochemical between sterilization conditions. As a result of sensory evaluation, most sensory evaluation inspector judged that it was difficult to distinguish the sensory difference of both products sterilized at Fo 9 min and at 11 min. The results showed that sterilization of Fo 9 min was more desirable than that of Fo 11 min to prepare canned salt-fermented anchovy fillet using tomato paste sauce, because this condition is more economical.

• 한방재활의학과학회지
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• 제21권2호
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• pp.49-62
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• 2011

Objectives : This study was designed to examine the effects of Polygonatum odoratum EtOH ext. on lowering lipid and anti-oxidation using hyperlipidemic rat. Methods : Male rats weighting $195.21{\pm}4.93g$ were divided into 4 groups and fed high fat diet for 8 weeks. Each of 7 rats was divided into a control and sample group. We fed a control group of rats a basal diet and administered normal saline(100 mg/kg, 1 time/1 day) for 4 weeks. And we fed each experimental group of rats basal diet and administered an extract of Polygonatum odoratum(100 mg/kg, 200 mg/kg, 300 mg/kg, 1 time/1 day) for 4 weeks. At the end of the experiment, the rats were sacrificed to determine their chemical composition. We measured lipid of plasma and liver, concentration of anti-oxidative activity and tumor necrosis factor-$\alpha$($TNF-{\alpha}$). Results : 1. Concentration of plasma free fatty acid, low density lipoprotein-cholesterol showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. Concentration of plasma total cholesterol, triglyceride showed a significant decrement in all Polygonatum odoratum EtOH ext. groups than that of control group. However, concentration of plasma high density lipoprotein-cholesterol was not significantly different in all the treatment groups. 2. Concentration of liver total cholesterol showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. Concentration of liver triglyceride(TG) showed a significant decrement in all Polygonatum odoratum EtOH ext. groups than that of control group. 3. Concentration of plasma thiobarbituric acid reactive substance, and liver thiobarbituric acid reactive substance showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. 4. The values of glutathione peroxidase activity showed a significant increment in all Polygonatum odoratum EtOH ext. groups than that of control group. The values of superoxide dismutase activity and catalase activity showed a significant increment in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. 5. The values of plasma aspartate aminotransferase and alanine aminotransferase activities were not significantly different in all treatment groups. 6. Concentration of liver $TNF-{\alpha}$ showed a significant decrement in the 200 mg/kg and 300 mg/kg Polygonatum odoratum EtOH ext. groups than that of control group. Conclusions : Based on the results in this study, the Polygonatum odoratum EtOH ext. showed a positive effect in lowering lipid and anti-oxidation.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.293-294
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• 2011

It is known that semiconductor quantum-dot (QD) heterostructures have superior zero-dimensional quantum confinement, and they have been successfully applied to semiconductor laser diodes (QDLDs) for optical communication and infrared photodetectors (QDIPs) for thermal images [1]. The self-assembled QDs are normally formed at Stranski-Krastanov (S-K) growth mode utilizing the accumulated strain due to lattice-mismatch existing at heterointerfaces between QDs and cap layers. In order to increase the areal density and the number of stacks of QDs, recently, sub-monolayer (SML)-thick QDs (SQDs) with reduced strain were tried by equivalent thicknesses thinner than a wetting layer (WL) existing in conventional QDs (CQDs) by S-K mode. Despite that it is very different from CQDs with a well-defined WL, the SQD structure has been successfully applied to QDIP[2]. In this study, optical characteristics are investigated by using photoluminescence (PL) spectra taken from self-assembled InAs/GaAs QDs whose coverage are changing from submonolayer to a few monolayers. The QD structures were grown by using molecular beam epitaxy (MBE) on semi-insulating GaAs (100) substrates, and formed at a substrate temperature of 480$^{\circ}C$ followed by covering GaAs cap layer at 590$^{\circ}C$. We prepared six 10-period-stacked QD samples with different InAs coverages and thicknesses of GaAs spacer layers. In the QD coverage below WL thickness (~1.7 ML), the majority of SQDs with no WL coexisted with a small amount of CQDs with a WL, and multi-peak spectra changed to a single peak profile. A transition from SQDs to CQDs was found before and after a WL formation, and the sublevel of SQDs peaking at (1.32${\pm}$0.1) eV was much closer to the GaAs bandedge than that of CQDs (~1.2 eV). These revealed that QDs with no WL could be formed by near-ML coverage in InAs/GaAs system, and single-mode SQDs could be achieved by 1.5 ML just below WL that a strain field was entirely uniform.