• Journal of the Korea Concrete Institute
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• v.18 no.3 s.93
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• pp.405-414
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• 2006

In the present study, a numerical analysis was performed for interior connections of continuous flat plate to analyze the effect of design parameters such as column section shape, gravity load and slab span on the behavioral characteristics of the connections. For the purpose, a computer program for nonlinear FE analysis was developed, and the validity was verified. Through the parametric study, the variations of shear stress distribution around the connection were investigated. According to the result of numerical analysis, as the length of the cross section of column in the direction of lateral load increases and gravity load increases, the effective area and the maximum shear strength providing the torsional resistance decrease considerably. And as the slab span loaded with relatively large gravity load increases, the negative moment around the connection increases and therefore the strength of connection against unbalanced moment decreases. By considering the effect of design parameters on the strength of the connections, the effective shear strength to calculate the torsional moment capacity of connection was proposed and the effectiveness of the proposed shear strength was verified.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.87-94
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• 2009

KNI3126 which is the eco-friendly material made by plant extracts - neem and matrine - have been evaluated for efficacies against 6 main pests and toxicity on natural enemies. Insecticidal efficacies of KNI3126 against plant hopper were above 95% at 5 days after treatment (DAT), whereas pesticidal effects against the cotton aphid were above 95% at 3 DAT and slightly decreased at 5 DAT. Insecticidal efficacy against the palm thrips resulted in lower control value as 68.1% than that of chemical insecticides. KNI3126 showed more than 95% control value against diamond back moth, suggesting that it could suppress the population of pest hard to control as eco-friendly material. Mortalities against two-spotted spider mite were about 80% at 1 DAT and over 90% at 5 DAT, respectively. For evaluation of the toxicity on natural enemies, effect against predatory natural enemy was classified as moderate selective toxicity based on the criterion of International Organization of Bio-Control (IOBC), whereas against parasitic natural enemies was found to be relatively safe. Repellent effect was weak against plant hopper, but strong against two-spotted spider mite. In the toxicity test for safety, KNI3126 was classified as the lowest level at acute oral, acute dermal and fish toxicity test and did not induce the irritancy at skin irritation test and eye irritation test.

• Spatial Information Research
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• v.10 no.1
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• pp.1-14
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• 2002

Due to the rapid development in information technology, countries of advanced information technology and multi-national information communication industries have expanding their invesment in constructing a cyber territory or a cyber city, and even a cyber globe that combines the real world with the cyber world. As such, in order to keep up with the competition with other countries to secure the Invisible Continent, Korea cannot afford to fall behind in the preparation and efforts to construct a cyber territory. Therefore in preparation for the inevitable establishment of a cyber territory, this study defined the concept of a cyber territory clearly and proposed a promotional strategy needed by the government for the establishment of a cyber territory. A cyber territory is 'the dynamic second territory that realizes various values in various aspects through organically combining innumerable active bodies in a surreal space and that are created by systematically and optimally connecting the physical topographical space and activity of the first nation to the cyberspace'. To explain further, a cyber territory is defined as another simulated space not only to manage the land systematically and deal with administrative services far the greater population, but also to contain economic activities of corporations and the citizens' everyday lives in a virtual reality by digitizing the entire territory including even the sea. In order to establish such cyber territory, it is necessary to revise related laws and policies, to foster related technology and industry as a main engine for national development, to promote public awareness, and to train related human resources.

• KOMUNHWA
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• no.61
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• pp.45-65
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• 2003

The Datuotou culture is a bronze age culture in the Jing and Jin region dating from the twenty-second century to the fifteenth century B.C. As an independent culture, it succeeded the last Neolithic tradition of the region and absorbed the neighboring loc

• Journal of Life Science
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• v.22 no.5
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• pp.657-664
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• 2012

The aim of this study is to screen a therapeutic agent with a cognitive function. The inhibitory effect of $Curcuma$ $longa$ hot water extract (CLWE) on the angiotension-converting enzyme and acetylcholinesterase derived from rabbit lungs and neural cells (PC12), as well as its antioxidant effect, was investigated in this study. Thus, for the first time, the direct scavenging effect of CLWE on DPPH radicals, superoxide anions, hydroxyl radicals, lipid peroxidation, reducing power, and the protective effect of DNA oxidation related to oxidative stress was evaluated in vitro. In addition, it was observed that CLWE especially exhibited a scavenging effect on reducing power and superoxide anions in this study. CLWE showed a protective effect on DNA oxidation produced by hydroxyl radicals. Furthermore, CLWE inhibited the activity of angiotensin-converting enzymes above 0.25%. Additionally, the extract inhibited oxidative stress and inducible nitric oxide in neuronal cells. Therefore, these results demonstrated that CLWE has antioxidant activity and neuronal cell protective effects, suggesting that it may have great potential as a natural source for human health.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.569-575
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• 1982

Mechanical properties of rice plants were tested to determine compressive force, bending force, tensile force and shear force for improvement of harvesting machines and for efficient utilization of rice culm during the proper harvesting period. Rice varieties used in this study were two Japonica varieties with Irri 348 and Jinju, and two $Indica{\times}Japonica$ hybrids with Seogwang and Taebaeg, which were grown in the standard fertilization field of Chungnam Rural Development Office. Also Jinju and Taebaeg were tested to elucidate the shearing characteristics which included shear force-strain relationship, shear force and shear energy according to the position from the ground level, the shearing angle to the rice culm, and the moisture content. 1. Compressive force, bending force, tensile force and shear force were higher In Japonica varieties than $Indica{\times}Japonica$ hybrids. 2. Shear force to overall culm length decreased progressively to upper positions in Jinju variety but a constant shear force was approximately showed between the ground level and the position of 21cm in Taebaeg variety. 3. Shear force and shear energy increased with increase of the cross sectional area, and the rates of increase were high in general up to the cross sectional area of $10mm^2$ and then they became dull very much. 4. Shear force and shear energy decreased with decrease of moisture content of rice culm after cutting up to the moisture content of 60% (w. b.) and then they did not change significantly.

• Korean Journal of Agricultural Science
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• v.16 no.2
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• pp.129-137
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• 1989

This experiment was undertaken to clarify derivation of resistance of Tongil type of rice varieties to rice blast in Korea and to classify Tongil type of rice varieties on the basis of their rice blast reactions in th blast nursery test. 1. The resistance of Tongil, Josaengtongil, Yeongnamjosaeng, Hwanggeumbyeo, Honamjosaeng, Noupung, Milyang 21, Milyang 22, Milyang 23, Raekyung, Manseogbyeo, Yongmunbyeo and Yongjubyeo to rice blast was derived from IR 8 or IR 24. 2. The resistance of Milyang 20, Nampungbyeo and Milyang 42, and Samseongbyeo, Seogwangbyeo, Pungsanbyeo and Shingwangbyeo to the rice blast was derived from IR 946 and IR 1539, and IR 1545, respectively. 3. The resistance of Palgwangbyeo, Sujeongbyeo, Hangangchalbyeo, Baegunchalbyeo, Samgangbyeo and Weonpungbyeo, and Taebaegbyeo and Chupungbyeo, and Kayabyeo to the rice blast was derived from IR 2061(IR 29), IR 747 and IR 32, respectively. 4. Cheongcheongbyeo, and Jungweonbyeo and Namyeongbyeo, and Changseongbyeo to the rice blast was derived from IR 2035, IR 5533, and HR 2797 and HR 1671, respectively. 5. Tongil type of rice varieties was classified into Tongil group, Milyang 30 group, Baegyangbyeo group and Taebaegbyeo group.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.307-316
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• 1993

The potential of using GIS in analyzing pest surveillance data was explored. The Spatial Analysis System (SPANS) was used to construct a spatial data base to study pest distributions using pest surveillance data collected from 152 stations in South Korea. The annual spatIal distributions of the striped rice borer(SRB), Chdo suppressalis, showed that high densities started to expand in the early 1980s, reaching a peak in 1988. The pattern change appears to be related to cultivation of japonica and indica-japonica hybrid varieties in South Korea. Japo7l!ca varieties have longer duration resulting in the SRB haVlng more time to mature and hibernate in wmter. The locus of SRB spread appears to be located in the mid-west region near lri, Chun~ Buk Province. High brown planthopper (BPH) populations in South Korea are often related to the early immigration and temperature. The simulated distribution of PPH densities in September using these two factors was compared with the actual distribution obtained using 1990 data. The two density maps corresponded closely excepL for differences in the south eastern valley. By overlaying the simulated map layer with the elevation and rice area maps, more specific BPH risk zones could be identified.

• Korean journal of applied entomology
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• v.14 no.2 s.23
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• pp.53-58
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• 1975

The local variabilities of resistance to Malathion and NAC (Sevin) were studied during 1973 with the strains of small brown planthopper (Laodelphax striatellus Fallen) collected from Jinjoo, Sunsan, Milyang, Kwangjoo and Iri districts of southern part of Korea. The susceptible lab strain used for this study has been reared successively in the laboratory without exposure to any insecticide since 1970. The insecticides were applied topically in acetone to the thoracic sternum of the adult insects. $LD_{50}$ values of Malathion to the insect were varied with the locality of the planthoppers. Relatively high levels of resistance to Malathion were observed in the strains of Jinjoo and Suntan; showing 27.7 times in female and 24.9 times in male for Jinjoo stram and 18.4 times in female and 13.8 times in male for Sunsan strain as compared with the susceptible lab strain, and in other strains of Milyang, Kwangjoo and Iri the levels of resistance to Malathion were still less than 5 times. However, there was no any specific difference among the strains in susceptibility to NAC. The malathion-resistant strain of the small brown planthopper seemed to be still localized in some regions of· Korea. The susceptibility of the planthoppers to Malathion was varied with the sex; $LD_{50}$ values based on the individual (ug/insect) were higher in female than in male, while the values based on the body weight (ug/g) conversely higher in male than in female.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.503-508
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• 2009

Biological-control-based-integrated-pest-management of major pests occurring on sweet pepper in greenhouse during summer season was tried. As many as 2.1 Orius laevigatus per $m^2$ were released in two times on June 6 and 19, and the population of thrips was kept under control and accordingly the damage was negligible throughout the season. To control aphids, a total of 0.8 Aphidius colemani per $m^2$ were released in four times, 0.2 of them at a time, flonicamid on May 14 and July 18 and pymetrozine on June 14 and September 4 were sprayed on the spots of high aphid occurrence to reduce the release of the wasp, and the density of aphids was kept under control. Whitefly was controlled successfully by releasing a total of 343.4 Amblyseius swirski per $m^2$ in nine times, 38.1 of them at a time, from May 9 until November 12 and dinotefuran was sprayed on November 12 when the density of whitefly increased up to 200 per trap. Tetranichus kanzawai was controlled by both Phytoseiulus persimilis which was released a total of 44.4 per $m^2$ in five times 8.9 of them at a time from May 23 to September 10, and the A. swirski which was released for the control of whitefly.