• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.3
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• pp.222-228
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• 2008

We conducted a dynamic analysis of an underwater test collector, which operates on extremely soft soil of deep-seafloor. The underwater test collector consists of nodule pick-up device, vehicle tracks, nodule crusher, loading frame and electric-electronic system. The weight of underwater test collector is about 8600 kg. The average normal pressure, that the underwater test collector supports, is about 6.0 kPa. The dynamic analysis model of underwater test collector is developed using commercial software RecurDyn-LM and Visual Fortran 90. A terramechanics model of extremely soft soil is implemented to the software based on user-written subroutine and applied to the dynamic analysis of the underwater test collector model. The dynamic responses of test collector are studied with respect to track velocities, terrain conditions, and coefficients of added mass and drag.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.2
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• pp.131-137
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• 2002

Purpose: To evaluate and compare the functional results, activity status, and anterior stability between conservative group with partial ACL injury and reconstruction group with bone-patellar ten-don-bone autograft in ACL total rupture. Materials and Methods: Thirty-eight patients with ACL injury were diagnosed and treated with arthroscopy and followed for more than two years. The number of patients with partial injury was 12(mean age; 38.3) and reconstruction group was 26 (mean age; 25.3). Objective stability was estimated under anterior loading of 15 lb and 20 lb by KT-2000 Arthrometer (MED metric, USA). Functional evaluation using Lysholm score and Tegner activity score were performed. Results: Average functional score of Lysholm was 88.5 in partial injury group and 89.3 in reconstruction group. Average score of Tegner was 5.3 in partial injury group and 5.1 in reconstruction group(P<0.05).Average anterior displacement compared with normal side. Under loading of 20lb, 1.7$\pm$4.3 mm in partial injury group, 2.3$\pm$1.9 mm in reconstruction group were anterior displaced (P<0.05). Under loading of 15lb, 1.2$\pm$1.0 mm in partial injury group, 1.4$\pm$1.5 mm in reconstruction group were dis-placed (P<0.05). There were giving way, effusion, instability and anterior knee pain in complication. Giving way was the frequent complication in the partial injury group. Conclusions: Clinical results of both group were similar. Functional evaluation of Lysholm was good and status of Tegner activity was maintained to physical fitness activites (jogging, regular bik-ing) in both groups on average. The results of conservative treatment for the partial ACL injury (less than 50$\%$) was satisfactory and equivalent to that of reconstructive treatment for the total ACL injury.

• Asian Journal of Business Environment
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• v.2 no.1
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• pp.25-34
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• 2012

It is possible to use pallet for forwarding as chinese cabbages and radishes are general large-scale trading items at the agricultural wholesale market though, however, most of these are forwarded as it have packed in net bags or in P·E bags. Thus, it is still hard for palletizing. The type of packing the product in the net bag makes it difficult for palletizing. It is not a stable shape enough and easily collapsed for pallet loading. Because of this collapsibility, the corrugated cardboard box is being used to enhance forwarding efficiency, but the existing corrugated cardboard box could be crushed easily by moist what is from the agricultural product's property and it also could be squashed by the mass of the loaded box layers on itself. In contrary, the functional waterproof corrugated cardboard box is not collapsed through palletizing and it is efficient for product management with it's ventilation function in respond to pre-cooling effect. Furthermore, because it has various functional shapes as the open type, the partition type and so on, it is effective for maintaining freshness of the product and standardizing the distribution of agricultural product. It is well-known that it is possible to introduce this box to cargo-works of agricultural product. Consequently, the recognition of main distributors about the pallet distribution of the chinese cabbage and the radish was apprehended in this study for activating mechanization of loading and unloading. The survey was conducted to the main distributors such as the forwarder, the auction dealer and the commission merchant with Garak-dong wholesale market as the center. The appropriate packing materials and problems of the existing method for loading and unloading were derived through the survey. Especially, it was focused on analyzing the difference of recognition between the subject groups for the way of using waterproof cardboard corrugated box to deal with the difficult product for packing in normal corrugated box because of the box's absorption of moist from the agricultural product like a chinese cabbage and a radish. Total In the cases of the forwarders and the commission merchants, the net was highly responded as 45%, 74% from each groups for the best packing material for mechanization of distribution and the waterproof corrugated cardboard box was responded as 20%, 22% from each groups as much preferable than multi-stage wooden box. However, for the radish, the waterproof corrugated cardboard box was the best material as 56%, and the auction trader group supported it for 80%. So, the using the waterproof corrugated cardboard box for mechanization of distribution was negative for the chinese cabbage, but it was positive for the radish. The average was 2.42, the standard deviation was 1.24. The negative response(about 55%) was prevailing more than positive response(about 23%). It could be analyzed that even there was the positive recognition for using the waterproof corrugated cardboard box for the radish though the preference for low price of net bag in the chinese cabbage forwarding procedure. Still now, it seems that is a burden for using the waterproof corrugated cardboard box with high price. In the analysis on the recognition differences about using the waterproof corrugated cardboard box for the chinese cabbages and the radish between the forwarders and the commission merchants, generally the negative recognition was prevailing, but the forwarders(2.696) were more positive for using the waterproof corrugated cardboard box than the commission merchants(2.145).

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.989-994
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• 2007

This study was designed to investigate whether Sasa borealis leaves extracts (SLE) may inhibit yeast ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities and postprandial hyperglycemia in STZ-induced diabetic mice. Freeze-dried SLE was extracted with 70% methanol and followed by a sequential fractionation with dicholoromethan, ethylacetate, butanol, and water. Both ethylacetate and butanol fractions showed high inhibitory activities against the ${\alpha}-glucosidase$ and ${\alpha}-amylase$ enzymes. The $IC_{50}$ of ethylacetate and butanol fractions against ${\alpha}-glucosidase$ were 0.54 and 0.63 mg/mL, respectively, indicating a greater inhibition effect than acarbose (0.68 mg/mL) (p<0.05). Likewise, the two fractions exhibited a smaller $IC_{50}$ against ${\alpha}-amylase$, compared with acarbose (p<0.05). However, the yield of ethylacetate fraction of SLE was relatively small. Postprandial blood glucose testing of normal mice and STZ-induced diabetic mice by starch soln. loading (2 g/kg B.W.) showed that postprandial blood glucose level at 30, 60, and 120 min were markedly decreased by single oral administration of SLE butanol fraction (200 mg/kg B.W.) in both normal (p<0.0l) and diabetic mice (p<0.0l). Furthermore, the incremental area under the curve (AUC) was significantly lowered via SLE administration (5,745 versus 12,435 $mg{\cdot}mim/dL$) in the diabetic mice (p<0.0l). The incremental AUC in normal mice corroborated the hypoglycemic effect of SLE (p<0.0l) found in the diabetic mice. These results suggest that SLE may delay carbohydrate digestion and thus glucose absorption. In addition, SLE may have the potential to prevent and treat diabetes via its ability on lowering postprandial hyperglycemia.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.8-12
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• 1974

1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.357-371
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• 1996

Lithium (Li) is known to be used not only during acute manic psychosis but also acute depressive phase in manic-depression. In the present study, it was attempted to investigate the effect of lithium on catecholamine (CA) secretion from the isolated perfused rat adrenal gland and to clarify the mechanism of its action. Replacement of $Na^+$ (118.4 mM) by lithium in the normal Krebs-bicarbonate solution used to perfuse the gland produced gradually an increased response in the spontaneous catecholamine release, which was peaked at $30{\sim}60$ min after its perfusion. Li-Krebs solution was perfused into an adrenal vein for 2 hours in every experiments. Li-Krebs-evoked CA secretory responses were depressed significantly under loading with $Ca^{++}-free$ medium. This CA secretion evoked by lithium loading was also reduced markedly by the pretreatment with nicardipine ($10^{-6}$ M), TMB-8 ($10^{-5}$ M) and chlorisondamine ($10^{-6}$ M) for 20 min, respectively, while was not affected by preloading with a pirenzepine ($2{\times}10^{-6}$ M)-containing Krebs. $Na^+$ pump inhibition by pretreatment with ouabain ($10^{-4}$ M) for 20 min did make the marked depression in Li-evoked CA secretory responses. Moreover, Li-evoked CA release was also diminished markedly by preloading with tetrodotoxin ($5{\times}10^{-7}$ M)-contaming Krebs for 20 min. All these experimental results taken together suggest that lithium enhances CA secretion in a $Ca^{++}$-dependent fashion by its accumulation in the adrenomedullary chromaffin cells of the rat, and that this secretory effect may be meidated by a dual mechanism: (i) chromaffin cell depolarization and subsequent opening of voltage-sensitive $Ca^{++}$ channels and (ii) activation of a $[Li]_i-[Ca]_0$ counter-transport system.

• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.479-485
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• 2011

The cardiopulmonary responses during total intravenous anesthesia (TIVA) between remifentanil/propofol infusion and remifentanil/ketamine infusion in dogs were compared. Fourteen healthy adult beagle dogs were premedicated with acepromazine (0.1 mg/kg, SC) and medetomidine (20 ${\mu}g$/kg, IV), and anesthetized for 3 hr with remifentanil (0.5 ${\mu}g$/kg/min)/propofol (loading dose: 1 mg/kg, CRI: 0.3 mg/kg/min) CRI (group 'P') or remifentanil/ ketamine (loading dose : 5 mg/kg, CRI: 0.1 mg/kg/min) CRI (group 'K'), respectively. Hemodynamics, blood gas analysis and behavioral changes during recovery were measured. The level of anesthesia was determined by toe-web clamping test. The level of surgical anesthesia was maintained throughout the experiment in both groups. Systolic arterial pressure, mean arterial pressure, $PaO_2$ and $SpO_2$ in group 'K' were significantly higher than in group 'P', and were maintained near the normal ranges. In addition, $PaO_2$ in group 'K' was significantly lower than in group 'P'. However, diastolic arterial pressure, heart rate and respiratory rate were not significantly differed. Mean extubation time from the end of infusion was significantly reduced in group 'K', but mean sitting time was significantly reduced in group 'P'. Mean head-up time and mean walking time were not significantly differed. In group 'K', brief muscle rigidity, head waving and licking during recovery were observed. In conclusion, infusion rate of ketamine (0.1 mg/ kg/min) with remifentanil (0.5 ${\mu}g$/kg/min) is an appropriate for obtaining the surgical plane of anesthesia. These results showed that group 'K' had better cardiopulmonary function than group 'P'. That is, remifentanil/ketamine CRI is better TIVA protocol than remifentanil/propofol CRI for 3 hr surgery.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2A
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• pp.89-96
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• 2011

The damping ratio as an index of bridge vibration could be considered as one of the important dynamic characteristics of a suspension bridge. But estimating of damping ratio on an existing suspension bridge under ambient vibration condition could be a laborious task. Moreover, it is not simple to directly distinguish aerodynamic damping and friction damping from apparent damping. According to previous studies, the aerodynamic damping properties can be linearly affected by wind speed level, and apparent damping ratio can be affected by amplitude of vibration. Therefore, in this article, the relationships among damping ratio, wind speed level and amplitude of acceleration were studied for separating extract aerodynamic damping and friction damping from apparent damping. Damping ratios on Sorok Bridge, a suspension bridge which is a located in Go-Heung, Korea, were estimated by two different methods as using Hilbert transform and extended Kalman filter which were well known as effective estimation methods for non-linear state. It was possible to distinguish aerodynamic damping and friction damping from apparent damping using averaged normal components of wind speed, RMQ values of acceleration, and estimated damping ratios from wind-induced vibration responses and vehicle loading responses.

• Korean Journal of Veterinary Research
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• v.43 no.2
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• pp.289-294
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• 2003

This study aimed to determine of osseointegration following dental implantation in the dog mandible using bone scintigraphy. Five mongrel dogs, weighing approximately 8.5 kg and averaging 1.8 years of age, without active periodontal disease were used. During the entire study period, all dogs were fed a soft commercial diet and water ad libitum to minimize functional loading of the implant. Titanium alloy implant systems 10 mm in length and 4 mm in diameter were chosen for insertion. Twelve weeks prior to implantation, the second and third left mandibular premolars in each dog were extracted for the dental implant insertion. Before the dental implantation procedures and 0, 4, 8, and 12 weeks after the insertions, clinical observation, radiography and bone scintigraphy were conducted. The scintigraphy was obtained using a large field of view gamma camera equipped with a paralled-hole, low-energy collimator about 3 hours after intravenous injection of Tc-99m-MDP (8 mCi/dog) to the dogs. There were not inflammation sign after insertion of dental implants on the mandible in dogs. Implants were slightly movable at the first and fourth weeks, and there was no mobility after 8 weeks. Twelve weeks after dental implantation, the bone uptake scintigraphy of peri-implant bone was similar to that of normal alveolar bone, indicating that peri-implant bone was completely regenerated by new bone. In conclusion, we recommend stable implant fixation with alveolar bone for the accurate and safe repair of teeth loot due to decacy, trauma or peridontal disease. Titanium alloy implants were optimal due to their biocompatibility.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.2
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• pp.170-178
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• 2015

In this study, it was developed eco-friendly alkali-activated slag fiber reinforced concrete using ground granulated blast furnace slag, alkali activator (water glass, sodium hydroxides), and steel fiber. Eight reinforced concrete beam using alkali-activated slag concrete were constructed and tested under monotonic loading. The major variables were mixture ratio of alkali activator, mixed/without of steel fiber. Experimental programs were carried out to improve and evaluate the flexural performance of such test specimens, such as the load-displacement, the failure mode, the maximum load carrying capacity, and ductility capacity. All the specimens were modeled in scale-down size. The reinforced concrete beams using the eco-friendly alkali-activated slag fiber reinforced concrete was failed by the flexure or flexure-shear in general. In addition, the maximum strength increased with the adding the mol of sodium hydroxide, and the specimen reinforced the steel fiber showed the value of maximum strength which is increased by 15.8% through 25.9%. It is thought that eco-friendly alkali-activated slag fiber reinforced concrete can be used with construction material and product to replace normal concrete. If there is applied to structures such as precast concrete member and production of 2nd concrete product, it could be improved the productivity and reduction of construction duration etc.