• Journal of Korean Physical Therapy Science
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• v.10 no.2
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• pp.96-103
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• 2003

The purpose of this study was to assess the effect of applied pressure to abdomen on lumbar and abdominal muscle activation during upper limb exercise. The experimental group consisted of twenty-seven healthy male subjects (mean age=$22.40{\pm}2.19years$, mean height=$175.30{\pm}2.19cm$, mean weight= $67.67{\pm}7.44kg$, RM=$8.43{\pm}2.76kg$). In each different pressure condition (OmmHg, 30mmHg, 70mmHg, 100mmHg), upper limb exercise was performed in total of 10 trials with 10 RM dumb-bell exercise. Lumbar and abdominal muscle activity was measured using surface bipolar electrode electromyography(EMG). EMG activity was measured from upper rectus abdominis, external oblique abdominis, internal oblique abdominis, and elector spinae. The raw EMG signal was processed into the root mean square(RMS). All RMS EMG data were normalized and express as a percentage of the EMG(%EMG). Collected data were statistically analyzed by SPSS/PC Ver 10.0 using two-way analysis of variance for repeated measures($4{\pm}3$) and Bonferroni post hoc, test. Lumbar and abdominal muscle activation was significantly increased when 100 mmHg was applied(p<.05). Upper rectus abdominis activation was significantly increased compared as other muscles activation(p<.05). However, there were no interaction between pressure and muscles(p>.05). The findings of this study can be used as a fundamental data when lumbar orthosis is applied and external pressure can be used as a therapeutic tool.

• Magazine of the Korea Concrete Institute
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• v.7 no.1
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• pp.117-125
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• 1995

Bond test was carried out to assess the effect of several variables on bond characteristics between reinforcing bar and concrete. Key variables are concrete compressive strength($f_c$'=340, 460, 6513, 904kg/$cm^2$), concrete cover (25, 38, 51, 105, IlOmm), and bar diameter(Dl3 and D22). Confining effect and bar spacing are not taken into account. Thirty-two specimens subjected to uniaxial tension were tested under hypothesis uniform bond stress distribution along the reinforcing bar embeded in concrete. Failure mode was examined and local bond stress versus slip relationship diagrams were represented to show effect of the above variables, also test results(u1timate bond stress) were compared with bond and development provisions of the ACI Building Code(AC1 318-89) and proposed equations from previous research. According to analysis, borld stress and ultimate bond stress increased although compressive strength increased beyond the ACI Building Code upper limit. Therefore in calculating development length. compressive strength effect(exceeding 700kg /$cm^2$) should be accounted.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.2
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• pp.195-201
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• 2012

According to many customers' requests, optical measurement module (OMM) applications using automatic measuring devices to measure the machined part rapidly on a machine tool have increased steeply. Touch trigger probes are being used for job setup and feature inspection as automatic measuring devices, and this makes quality checking and machining compensation possible. Therefore, in this study, the use of touch trigger probes for accurate measurement of the machined part has been studied and a macro program for a hole measuring cycle has been developed. This hole is the most common feature to be measured, but conventional methods are still not free from measuring error. In addition, the eccentricity change of the least square circle was simulated according to the roundness error in a hole measurement. To evaluate the reliability of this study, the developed hole-measuring program was executed to measure the hole plate on the machine and verify the roundness error in the eccentricity simulation result.

• International Journal of Korean Welding Society
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• v.2 no.2
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• pp.26-31
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• 2002

Considering the fuel consumption of car, a light structure of aluminum alloys is desired fer car body nowadays. However, fusion welding of aluminum alloys has some problems of reduction of joint efficiency, porosity formation and hot cracking. In the present work, investigation to improve the joint performance of laser welded joint has been carried out by addition of Cu, Ni, and Zr to A6NO 1 alloy welds. Aluminum alloy plate of 2.Omm in thickness with filler metal bar was welded by twin beam Nd: YAG laser facility (total power: 5kW). The filler metals were prepared by changing the chemical compositions for adding the elements into the weld metal. Thirteen filler metal bars were prepared and pre-placed into the base metal before welding. Ar gas shielding with a flow rate of 10 1/min was used. The defocusing distance is kept at 0 mm. At travel speeds off 3 to 9 and at laser power of 5kW (front beam 2kW rear beam 3kW), full penetration welds were obtained, whereas at travel speeds of 12 to 18 m/min and same power, partial penetration was observed. The joint efficiency of laser-welded joint was improved by the addition of Cu, Ni, and Zr due to the solid solution hardening, grain refining and precipitation hardening. The type of hardening has been further considered by metallurgical examination.

• Magazine of the Korean Society of Agricultural Engineers
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• v.25 no.2
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• pp.86-95
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• 1983

Evapotranspiration is a major factor determining the water consumption in the rice fields. Therefore, realistic evapotranspiration estimates are important to the agricultural water resources planning. In Korea, however, the Blaney-Criddle formula, which was developed under the meteorological condition of western arid United States and the upland cultivation, has been widely used to estimate evapotranspiration from paddy fields. Hence, it has considered that the Blaney-Criddle formula would not be the proper method for the Korean paddy condition. The purpose of this study is to select the most appropriate and realistic method for estimating evapotranspiraion from paddy field in Korea and to derive crop coefficients using the chosen method. The results are summerized as follows. 1. Total seasonal-average evapotranspiration by the field observation was 660mm for Tongil and 621. Ornm for the Japonica variety of rice. The amount of evapotranspiration for Tongil variety was 6% larger than that of the Japonica variety. 2. There was no significant differences in the amount of evapotranspiration among early, middle and late mature varieties, that is, early 638mm, middle 627mm and late 630mm for the whole growing season. 3. The rate of peak evapotranspiration appeared at the beginning of August and was in the range of 7.7-8. Omm/day according to the different mature varieties. 4. The correlation between pan evaporation data and the calculated evapotranspiration using related meteorological data from various methods suggested such as Radiation (FAO), Hargreaves, Christiansen, Hargreaves-Christiansen, Jensen-Haise, showed high statistic significance. Therefore, it seemed to use those formulars in estimating evapotranspiration inste4 of using pan evaporation data. 5. It was concluded from the analysis of field data that the evapotranspiration estimate for Blaney-Criddle method might not be appropriate in Korea. On the other hand, Penman equation showed more accurate estimation at the flourishing stage of rice than the pan evaporation method. 6. The crop coefficients for the Penman and pan-evaporation method were obtained by graphical representation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.1
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• pp.9-17
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• 2012

This study is dealt with the experimental seam strength of deep corrugated steel plate which is used as underpasses, storm sewers and other buried applications. The soil-metal structure using deep corrugated plate should be sufficient to ensure safety for compressive loading. The experimental and theoretical results on the seam strength are accumulated enough to take the design guideline, even if the seam strength at the bolt connected lap joint in construction site can be varied depending on the connection detailing and the thickness of plate. In this study, compressive behavior of bolted lap jointed plates using various connection detail such as gasket, slot hole, washer was experimentally analyzed. From the test, failure pattern with an increases in the thickness of specimens was changed from plate bearing to bolt shearing. In case of thicker plates than 6.0mm, the structural performance of lap joint using gasket and slot hole is more effective than it of the plate adopted washer.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.4
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• pp.59-68
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• 1992

A Study was made to improve soil and water temperature and mechanized farming for a wetted paddy under the influence of artesian groundwater located at Samcheon-Dong, Chuncheon City, Kangweon Province. Half perforated PVC drainage pipes were installed in the test paddy to observe temperature change of water and soil. The temperature of the water in the paddy and soil itself raised significantly after the installation of the half perforated PVC pipes. A subsequent improvement of growth and yield of rice on the paddy was achieved. Harvesting operation was also improved with firm ground condition so that cutting and threshing could be done simultaneously within the paddy plot. Following results were obtained from the study. 1.Temperature of the water in a paddy under the influence of artesian groundwater was not changed notably although air temperature was fluctuated during the crop period. Soil temperature was mostly affected by the artesian groundwater. However, the half perforated PVC pipe drainage system made it possible to raise temperature of water and soil remarkably up to the level of optimum farming. 2.Total precipitation was 534.Omm during the crop period of the paddy for 118 days from May 26 to September 20 in 1992. Due to heavy rainfalls of 105.6mm and 109.8mm occurred on August 7 and August 27.1992, respectively, the rate of the artesian groundwater increased to 35 litter per minute with two to three days of time lag. 3.Average rate of the artesian groundwater was 28 litter per minute from the one year of observation. The rate varied by 0.7 to 1.3 times of average during the observation period. Peak rate of the artesian groundwater decreased to 14.5 litter per minute when daily precipitation maintained at the amount of 20 to 30mm for a long time period. Contrarily, it showed a tendency to increase to 35 to 40 litter per minute when heavier precipitation of 50 to l00mm occurred in a short period of three to five days. 4.Growth and yield of Yemyung variety of rice planted on the paddy that was facilitated with a drainage system with half perforated PVC pipes were confirmed at a normal level, while paddy without this perporated drainage system showed abnormal growth with low yield.

• Parasites, Hosts and Diseases
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• v.28 no.4
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• pp.235-240
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• 1990

During an investigation on intestinal flukes of house rats in Yangyang-gun, Kangwon-do, a total of 6 species of trematodes belonging to 3 families; Echinostom-atidae (Echinostoma hortense, E. cinetorchis, E. revolutum and Echinoparyphium recurvatum), Diplostomidae (Fibricoza seoulensis) and Plagiorchiidae (Plagiorchis muris), were recovered from two adult rats. E. revolutum and E. recurvatum were new trematode faunae of rats in Korea. 5. revolutum had an elongated body, 5.3∼6.Omm long and 1.0∼1.3mm wide. The total number of collar spines was 35∼37 including 5 end group ones on each ventral corner. Its coiled uterus contained numerous eggs.5. recurvatum also had an elongated body, 3.5∼4.7 mm long and 0.50∼0.65 mm wide. It had total 45 collar spines including 4 end group ones. The uterus toras short with only a few eggs. It has been first confirmed by this study that E. revolutum and E. recurvatum are indigenously distributed among house rats in Korea. Kef lords: Echinostoma revolutum, Echinoparyphium recurvatum. new fauna. house rats, Yangyang-gun ( Kangwon-do )

• Journal of Life Science
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• v.25 no.5
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• pp.577-584
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• 2015

Orostachys malacophyllus grow on the old roofing tile or on the rock of mountain and is belong to Crassulaceae family. After air drying for Orostachys malacophyllus (OM), using the mixture of lactic acid bacteria (Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus) was fermented (FOM). OM and FOM extracted using water (W), ethanol (E) and methanol (M) and were measured extracts yield, pH and Brix. Extracted OM and FOM were tested by in vitro experimental models of α,α´-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity, Fe/Cu reducing power, linoleic acid peroxidation using ferric thiocyanate and thiobarbituric acid (TBA) methods and peroxidation of rat liver homogenate. In addition, the bioactive materials (phenolic compounds, flavonoids and minerals) were measured. The highest phenolic compounds and flavonoids were OME 122.2 mg/100 g and OME 84.0 mg/100 g. OM and FOM′s major minerals were K, Ca and Mg. The highest free radical scavenging activity showed in FOMM (93.9%), OMM (93.4%), FOME (92.1%) and OME (91.9%) at 0.5% additional level. Fe reducing powers were strong in FOME and FOMM and Cu reducing powers were strong in OME and FOMM. Antioxidant activities on lipid peroxidation using rat homogenate as measured by TBARS method showed strong in FOME and on lipid peroxidation of linoleic acid as measured by ferric TBA method showed strong in OME and FOME and measured by ferric thiocyanate showed strong in FOME and FOMM.

• Journal of Periodontal and Implant Science
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• v.36 no.3
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• pp.661-671
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• 2006

The purpose of this study was to evaluate cumulative survival rate (CSR, %) of mandibular posterior single tooth implants replaced with ITI SLA (sand-blasted, large-grit, acid-etched) implant system and compare the CSR between first and second molar. The findings from the results were as follows; 1. Total of 158 implants were inserted into 147 patients. 68 patients were males, 79 patients were females and their mean age was 47.8 years. 98 implants were placed in first molar area and 60 implants were placed in second molar area. In terms of diameter, implants with wide diameter over 4.8mm dominated (91.1%). Implants with length over lOmm were used (96.2%). 2, In the two cases, there was a slight transient numbness which recovered within 1-2 months. Nine SynOcta screw type abutments demonstrated screw loosening, There were ten cases of crown fallen-out from decementation. 3. Only one failed out of 158 implants. The CSR was 99.4%. The CSRs for first molar and second molar were 99% and 100%, respectively. From the results, it was concluded that single tooth replacement implant in the mandibular posterior area, might be considered as the effective treatment modality comparable to the conventional crown and bridge.