• International Journal of Highway Engineering
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• v.14 no.3
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• pp.59-67
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• 2012

This study presents the evaluation of the patching materials that are used to repair the distress of asphalt pavement. Four kinds of patching materials currently used in practice were tested in both laboratory and field. The laboratory tests included the dry and soaked Marshall stability test, indirect tensile test, wheel tracking test and adhesive strength between the asphalt pavement and the repairing material was tested as a performance test. The field study was conducted using the slab samples placed on the location of vehicle tire passing and the performance of the repairing materials were investigated as passing the traffic load. The result of the laboratory tests were satisfied with the current design criteria and material standard except for water-immersion stability. Type C patching material showed the highest adhesive shear strength among the patching materials tested. However, the mature distress, such as rutting and stripping were monitored after construction in 10 days. It was found that performance of patching material is lack of quality behavior when they were applied in the field and required to develop and applu to prevent the mature distress of the current patching materials.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.311-323
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• 2005

This study tested the effect of a trivalent (feline panleukopenia; FPV, feline viral rhinotracheitis; FHV, feline calicivirus infection; FCV) inactivated vaccine in cats. The vaccine was tested for the safety in guinea pigs, mice and cats. Also, it was tested for the efficacy in cats. The vaccine was inoculated to cats at 7~9 and 10~12 weeks of age (conventional schedule) and the serological response to vaccination was assessed and was compared to the unvaccinated group. All cats were bled by jugular venipuncture for FPV, FHV and FCV specific serological test (virus neutralizing antibody, VN) at 7~9, 10~12 and 13~15 weeks. After last bleeding, all cats were inoculated with each virus (FPV : orally $2ml\;10^{7.5}\;TCID_{50}/ml$, FHV : nasally $1ml\;10^{7.0}\;TCID_{50}/ml$ and FCV : nasally $1ml\;10^{7.0}\;TCID_{50}/ml$). The Vaccine verified excellent protective effect in guinea pigs, mice and cats. The VN antibody titers of the unvaccinated group cats against FPV, FHV and FCV were <2~16, on the other hand the vaccinated group cats were $512{\sim}{\geq}4096$, 64~1024 and 64~1024, respectively. When all cats were challenged with virulent viruses, the survival rates of the vaccinated group cats were over 80%, while the survival rates of the unvaccinated group cats were less 20%. The typical clinical signs were not observed in the vaccinated group cats, but the typical clinical signs and histopathological lesions were observed in the unvaccinated group cats. As the result of tests, the VN values obtained in this study appeared to be high enough to protect cats from viral challenges. The trivalent (FPV, FHV, and FCV) inactivated vaccine seemed to be very effective, for prevention of feline viral diseases (FPV, FHV, and FCV).

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.5
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• pp.489-494
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• 2014

In this paper, a design of multiple channel wireless remote control system for unmanned vehicle is proposed. One of serious problems of the previous wireless remote control system is that it does not work when a control channel is damaged in case of emergency because it's composed of single control channel. Therefore, we propose the multiple channel wireless remote system which is composed of a portable wireless remote controller and a stationary wireless remote controller. The portable wireless remote controller and stationary wireless remote controller are designed and the multiple channel wireless remote control system for unmanned vehicles in developed. By applying to the unmanned vehicle to check its performance. The wireless remote control system is tested. Emergency stop using the portable wireless remote controller is tested when the stationary wireless remote controller is damaged. Also, emergency stop using the stationary wireless remote controller is tested when the portable wireless remote controller is damaged. The result of emergency stop test shows satisfied performance.

• Archives of Pharmacal Research
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• v.16 no.3
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• pp.196-204
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• 1993

Flavonol derivatives were tested for their anticlastogenic effect against induction of micronuclei by n-methyl-n'-nitor-n-nitorsoguanidine(MNNG), and against induction of chromosome aberration by bleomycin or MNNG.belomycin. For micronudeus assay, each flavonol derivative (0, 0.001, 0.01, 0.1, 1, 10 and 100 mg/kg) was administered orally twice with 24 h interval, together with intraperitioneally administered MNNG(150 mg/kg). The result showed that msot flavonol derivatives tested were effective in suppresing the frequencies of micronude induced by MNNG. For chromosome aberration assy, each flavonol derivative (0, 0.1, 1, 10m and 100 mg/kg)was administered to mice orally in vivo, and then mice were sacrificed and spleen lymphocyte cultures were made. Bleomycin $(3\;\mu$g/ml) was treated to the mouse spleen hymphocyte cultures at 24 h after con A initiation. There wre nomarked decrease tendencies in chromosome aberration unless all doses of galangin and some doses of several flavonol derivatives tested. In the another experiment, we have evaluated the effect of flavonol derivatives on the enhancement of bleomycin-induced chromsome aberration by MNNG. Most of flavonol derivtives reduced the incidence of chromosome aberration induced by in vitro treatment of bleomycin followed by in vivo treatment of MNNG. Galangin particulary showed a dose-dependent decrease tendency. Other flavonol derivative showed slightly suggest that most of flavonol derivatives may be capable of protecting the inhibition of suggest that most of flavonol derivatives may be capable of protecting the inhibition of DNA-repair by MNNG. Our data indicate clearly that flavonol derivatives can suppress MNNG-induced genotoxicity such as an induction of MNPCEs. Therfore, our results could suggest that flavonol derivtives may be useful as a chemopreventive agent of MNNG.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.3
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• pp.73-85
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• 2002

The purpose of this study was to develop prediction models for plant species abundance by stream restoration. Generally the stream plant is affected by stream gemophology. So in this study, the relationship between the vegetation abundance and stream gemophology was developed by multiple regression analysis. The stream characteristics utilized in this study were longitudinal slope, transectional slope, micro-landforms through the longitudinal direction, riparian width and geometric mean diameter and biggest diameter of bed material, and cumulated coarse and fine sand weight portion. The Pyungchang River with mountainous watershed and the Kyungan stream and the Bokha stream in the agricultural region were selected and vegetation species abundance and stream characteristics were documented from the site at 2~3km intervals from the upper stream to the lower. The Models for predicting the vegetation abundance were developed by multiple regression analysis using SPSS statistics package. The linear relationship between the dependant(species abundance) and independant(stream characteristics) variables was tested by a graphical method. Longitudinal and transectional slope had a nonlinear relationship with species abundance. In the next step, the independance between the independant variables was tested and the correlation between independant and dependant variables was tested by the Pearson bivariate correlation test. The selected independant variables were transectional slope, riparian width, and cumulated fine sand weight portion. From the multiple regression analysis, the $R^2$for the Pyungchang river, Kyungan stream, Bokga stream were 0.651, 0.512 and 0.240 respectively. The natural stream configuration in the Pyungchang river had the best result and the lower $R^2$for Kyunan and Bokha stream were due to human impact which disturbed the natural ecosystem. The lowest $R^2$for the Bokha stream was due to the shifting sandy bed. If the stream bed is fugitive, the prediction model may not be valid. Using the multiple regression models, the vegetation abundance could be predicted with stream characteristics such as, transection slope, riaparian width, cumulated fine sand weigth portion, after stream restoration.

• Journal of the Korean Society of Safety
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• v.27 no.6
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• pp.185-191
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• 2012

Rear collisions to expressway work trucks result many casualties these days. But, currently, no special measure are being taken except deploying sign trucks behind the working trucks. In the U.S and Europe, trucks with TMA(Truck Mounted Attenuator) are being deployed behind the working truck, which is regarded as the standard method for work area safety, thereby reducing the fatality rates and property damage tremendously. Also, standard for the performance of TMA are established and TMA can be used in the field only when it satisfies the standard. In Korea, neither the standard for nor any guide to the TMA exists. In the situation some manufacturer developed TMA without proper performance evaluation and marketed limited number of TMAs in the field. In the study, NCHRP350, which is the performance standard of expressway safety features of U.S. and materials related to the TMA standard in Europe have been reviewed to establish the Korean performance criteria. Based on the review, and incorporating existing Korean standard for crash cushions, domestic standard for TMA has been proposed and applied in developing Korean TMA and crash tested it to verify the performance. The original design developed was crash tested and modified. The newly proposed design was studied using impact simulation program several times. Modifications were made after each simulation and prototype was built and crash tested as per the newly established TMA performance criteria.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.7
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• pp.943-948
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• 2018

In this paper, we propose a hybrid approach of combining $A^*$ and Genetic algorithm in the path search problem. In $A^*$, the cost from a start node to the intermediate node is optimized in principle but the path from that intermediate node to the goal node is generated and tested based on the cumulated cost and the next node in a priority queue is chosen to be tested. In that process, we adopt the genetic algorithm principle in that the group of nodes to generate the next node from an intermediate node is tested by its fitness function. Top two nodes are selected to use crossover or mutation operation to generate the next generation. If generated nodes are qualified, those nodes are inserted to the priority queue. The proposed method is compared with the original sequential selection and the random selection of the next searching path in $A^*$ algorithm and the result verifies the superiority of the proposed method.

• Journal of Biosystems Engineering
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• v.27 no.2
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• pp.133-142
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• 2002

This is a fundamental study to develop a sensor to detect weeds in paddy field using machine vision adopted spectralphotometric technique in order to use the sensor to spread herbicide selectively. A set of spectral reflectance data was collected from dry and wet soil and leaves of rice and 6 kinds of weed to select desirable wavelengths to classify soil, rice and weeds. Stepwise variable selection method of discriminant analysis was applied to the data set and wavelengths of 680 and 802 m were selected to distinguish plants (including rice and weeds) from dry and wet soil, respectively. And wavelengths of 580 and 680 nm were selected to classify rice and weeds by the same method. Validity of the wavelengths to distinguish the plants from soil was tested by cross-validation test with built discriminant function to prove that all of soil and plants were classified correctly without any failure. Validity of the wavelengths for classification of rice and weeds was tested by the same method and the test resulted that 98% of rice and 83% of weeds were classified correctly. Feasibility of CCD color camera to detect weeds in paddy field was tested with the spectral reflectance data by the same statistical method as above. Central wavelengths of RGB frame of color camera were tried as tile effective wavelengths to distingush plants from soil and weeds from plants. The trial resulted that 100% and 94% of plants in dry soil and wet soil, respectively, were classified correctly by the central wavelength or R frame only, and 95% of rice and 85% of weeds were classified correctly by the central wavelengths of RGB frames. As a result, it was concluded that CCD color camera has good potential to be used to detect weeds in paddy field.

• Toxicological Research
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• v.35 no.2
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• pp.181-190
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• 2019

Lentinus squarrosulus (Mont.) is an edible wild mushroom with tough fruiting body that belongs to the family Polyporaceae. It is used in ethnomedicine for the treatment of ulcer, anaemia, cough and fever. Recent studies have demonstrated its anticancer, anti-diabetic and antioxidant properties. However, little or no information is available regarding the bioactive components and toxicological study of wild dried L. squarrosulus. Therefore, this study investigated the bioactive components of aqueous extract of boiled wild dried L. squarrosulus and its toxicological effects in rats. The extract of L. squarrosulus was subjected to GC-MS analysis. The acute toxicity test was performed by oral administration of a single dose of up to 5,000 mg/kg extract of L. squarrosulus. In subacute study, the rats were orally administered extract of L. squarrosulus at the doses of 500, 1,000 and 1,500 mg/kg body weight daily for 14 days. The haematological, lipid profile, liver and kidney function parameters were determined and the histopathology of the liver and kidney were examined. The GC-MS analysis revealed the presence of bioactive compounds; 1-tetradecene, fumaric acid, monochloride, 6-ethyloct-3-yl ester, 9-eicosene, phytol, octahydropyrrolo[1,2-a]pyrazine and 3-trifluoroacetoxypentadecane. In acute toxicity study, neither death nor toxicity sign was recorded. In the sub-acute toxicity study, significant differences (p < 0.05) were observed on creatinine, aspartate aminotransferase, alanine aminotransferase, total cholesterol, triglycerides and high-density lipoprotein cholesterol. Whilst no significant differences (p > 0.05) were observed on packed cell volume, heamoglobin, red blood cell, white blood cell and alkaline phosphatase, in all the tested doses. No histopathological alterations were recorded. Our findings revealed that aqueous extract of L. squarrosulus may have antimicrobial, antinocieptive and antioxidant properties based on the result of GC-MS analysis. Results of the toxicity test showed no deleterious effect at the tested doses, suggesting that L. squarrosulus is safe for consumption at the tested doses.

• Structural Monitoring and Maintenance
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• v.10 no.1
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• pp.1-23
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• 2023

Various efforts have been made to reduce the weight of concrete slabs while preserving their flexural strength. This will result in reducing deflection and allows the utilization of longer spans. The top zone of the slab requires concrete to create the compression block for flexural strength, and the tension zone needs concrete to join with reinforcing for flexural strength. Also, the top and bottom slab faces must be linked to transmit stresses. Voided slab systems were and are still used to make long-span slab buildings lighter. Eight slab specimens of (1000^*1000 (1000^*1000 mm²) were cast and tested as two-way simply supported slabs in this research. The tested specimens consist of one solid slab and seven voided slabs with the following variables (type of slab solid and voided), thickness of slab (100 and 125 mm), presence of steel fibers (0% and 1%), and the number of GFRP layers). The voids in slabs were made using high-density polystyrene of dimensions (200^*200^*50 mm) with a central hole of dimensions (50^*50^*50 mm) at the ineffective concrete zones to give a reduction in weight by (34% to 38%). The slabs were tested as simply supported slabs under partial uniform loading. The results of specimens subjected to monotonic loading show that the combined strengthening by steel fibers and GFRP sheets of the concrete specimen (V-125-2GF-1%) shows the least deflection, deflection (4.6 mm), good ultimate loading capacity (192 MPa), large stiffness at cracking and at ultimate (57 and 41.74) respectively, more ductility (1.44), and high energy absorption (1344.83 kN.mm); so it's the best specimen that can be used as a voided slab under this type of loading.