• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.229-236
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• 2011

This study was carried out to provide recent information on zoysiagrass (Zoysia spp.) sod production in Japan. Total zoysiagrass sod production acreage in Japan was 6,623 ha. The acreage by prefecture was 3,900 ha (58.9%) in Ibalaki, 779 ha (11.8%) in Tostoli, 609 ha (9.2%) in Kagosima, and 550 ha (8.3%) in Sijeumoka, respectively. Sod was harvested by 1.5 cm sod thickness. Mowing height of Goraisiba (Zoysia matrella) and Nosiba (Zoysia japonica) cultivars was cut by 10 mm and 25 mm height, respectively. Japan agricultural cooperative issued a warranty of sod production quality to zoysiagrass consumers. A quality evaluation for sod production was carried out continuously to maintain a reasonable degree of uniformity and hight quality of sod production three times a year. Also, zosiagrass sod production was rotated with Chinese cabbage (Brassica rapa var. glabra Regel) for improving fertility of soil every five to six years. Patented cultivars for promoting bland in Ibaraki prefecture of Japan were 'Tsukuba himae', 'Tsukuba kagayaki', 'Tsukuba Talou' and 'Tsukuba green'.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.197-197
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• 2017

In order to reduce the loss of perilla seeds at harvesting stage, different seeding methods and harvesting time had been applied to upland soil in NICS (National Institute of Crop Science), RDA, Milyang, Korea. The seeding methods were divided into hill and drill seeding, and harvesting time were 40%, 60%, 80%, and 100% color-changing of top cluster perilla (cv Deulsaem) seeds. Higher plant height and lowest flower cluster, thinner culm thickness was observed in drill seeding treated plot than hill seeding treated plot. However, field lodging occurred lower at drill seeding treatment (lodging degree 3) than hill seeding plot (lodging degree 5). Harvesting time affected the loss of perilla seeds and the loss rate of perilla seeds were investigated at different color-changing of top flower cluster. When seeds were harvested at 40%, 60%, 80%, and 100% color-changing of top cluster perilla seeds, the loss rate of hill and drill seeding showed no significant differences however the loss rated of 40, 60, 80, and 100 % color-changing of top flower cluster were 1.9% to 3.0%, 3.8% to 3.9%, 8.0% to 10.2%, and 16.1% to 22.7%, respectively. The harvesting time had no significant effects on the yield of perilla seeds. These results suggest that optimum harvesting time of perilla could be recommend at the 60% color-changing of top cluster to reduce the loss of perilla seeds.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.93-99
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• 2000

Treatment of shaving scrap, a chrome containing solid scrap generated by leather manufacturing process, has been so far depended on mainly incineration, soil landfill and ocean dumping, which give bad impact on environment and cause pollution. Shaving scrap generates from the mechanical work for controlling the final thickness of leather and its main components are collagen protein and pan of chromium compound. For the purpose of reusing this leather waste as resources, researches in connection with collagen fiber recovery, gelable protein recovery and liquid fertilizer is being speedily progressed. In the experiment, shaving scrap went through wet pulverizing treatment by physical and chemical methods. Then, making the leather sheet evenly, it is mixed with natural latex and every kind of binding materials in the container, and the mixtures were passed through experimental hydraulic press machine and applied to Fourdrinier machine respectively. Lastly, a test for fading out physical strength and properties of multiple-purpose of leather-like material was performed on a continuous leather sheet prepared by the experiment. In result, the physical strength and properties of leather-like material showed noticeable differences according to mixing ratio of binding materials, beating methods and the Ends of binding materials selected, and generally tear strength was the weakest property among others. Also, by the pilot scale experiment in sequence, it was possible to manufacture recycled goods made of soft and hard types of leather-like material with various performances.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.2
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• pp.54-63
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• 2014

Corrugated steel plate structure, which is built by assembling corrugated steel plate segments with bolts on site and filling the surroundings with quality soil, is widely used for buried structures as a eco-corridors, small bridges, and closed conduits. This experimental study is dealt with the static and fatigue performance of bolt connected corrugated steel plates under flexural loading. The experimental variables to verify the fatigue performance are bolt diameters and detailing of connection such as washer and the corrugation dimension of specimens has a $400{\times}150$ mm. The experimental ultimate strength of specimens under static loading was higher than the theoretical strength and all specimen failed by a bearing and tearing failure of bolt hole of upper plate. Therefore, a fatigue tests of specimens had 6.0mm and 7.0mm thickness was conducted in which the load range was up to 209kN and 516kN, respectively. From the fatigue test, failure patterns are changed from plate bearing and tearing which is a typical failure pattern of static failure to a bearing failure of plate and shear failure of bolt, and experimental fatigue limit at $2{\times}10^6$cycles is about 85MPa.

• Journal of Ginseng Research
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• v.28 no.3
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• pp.157-164
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• 2004

The study was conducted to investigate the tissue and chemical characteristics of rusty root epidermal cells. In histological study, the rusty symptoms were frequently observed in the epidermis of ginseng root and to be yellow under microscopic observation. Disks of the epidermal cell tissue of the rusty root were usually 2 and 3 times greater in the number of cell layer and thickness of cell wall than the healthy root, respectively. The color degree of methanol extracts from the rusty root epidermis was 5.5 times higher than that of the healthy root. And the extracts of rust matter in the root epidermis were easily dissolved in polar solvents compared to nonpolar solvents. UV-absorption spectra of methanol extracts in various fractions of phenolics showed a maximum peak between 275∼280 nm. The crude lipids and phenolic compounds such as acid insoluble bound phenolics, acid insoluble esterified phenolics, acid insoluble condensed phenolics, insoluble bound phenolics and free phenolics were also more in the rusty root epidermis than in the healthy one. Fe content in the rusty root epidermis was 2.7 times higher than that of healthy one. It was presumed that the phenolic compounds(precursor of the rusty) in association with lipid and iron in the root epidermis might defence the root when ginseng root was depressed by the unfavorable conditions in soil and/or portions of a root system were subjected to anoxic conditions.

• Journal of the Korean Geophysical Society
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• v.2 no.3
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• pp.209-216
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• 1999

In order to get geologic information necessary for underground installation of water pipe, seismic refraction profiling was applied to the southwest side of the Seomjin River which flows between Namwon-gun, Cholabuk-do and Gokseong-gun, Cholanam-do. Before obtaining the in-line refraction data, walkaway data were recorded with 1 m geophone interval and -36∼+36 m offset range. From the walkaway data, it is interpreted that a dry soil layer with the average velocity of 585 m/s covers wet sediments with the average velocity of 1,326 m/s. The second layer overlies basements nearly horizontally with the average velocity of 4,218 m/s. Refraction profiling of 220 m long with the geophone interval of 2 m is interpreted with the Generalized Reciprocal Method (GRM). Three layers are identified with average velocities of 688 m/s, 1,473 m/s, and 3,776 m/s, respectively. The depth to the bedrock impossible for ripping ranges between two extremes, 1.51∼2.43 m and 2.25∼3.54 m, depending upon thickness of the hidden layer. A typical shortcoming of refraction method, the hidden layer problem, prevents accurate estimation in depth of the second layer.

• Journal of the Korean Geophysical Society
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• v.3 no.4
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• pp.215-226
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• 2000

In order to map the acoustic basement and to locate fracture zones in the Galgok fault, seismic refraction data were acquired near the Chonbuk ranch in Gyeongju. Along three profiles of 72m(Line 1), 72m(Line 2), and 36m(Line 3) long, seismic signals were generated by a 5kg hammer. The refraction data were collected by employing twelve 8 Hz geophones at an interval of 3m and recording time of 192ms at a sampling rate of 0.2ms. The data are interpreted using GRM method. The top layer (Layer 1) is characterized as the velocity of approximately250 m/s and thickness of approximately 2.1m. This layer is regarded as a soil layer. Underneath Layer 1 lies unconsolidated layer (Layer 2) whose refraction velocity is determined to be $1,030{\sim}1,400m/s$. Layer 2 is approximately 4.6m thick and is regarded as a Quaternary gravel layer. The third layer (Layer 3) has the mean refraction velocity of $2,100{\sim}2,200m/s$ and is interpreted to be the acoustic basement. In some parts of Lines 1 and 3, the difference in depth to the top of Layer 2 is greater than 20 cm indicating the possibility of existence of Quaternary faults. Along Line 3 and the eastern part of Line 1, refracted energy from the acoustic basement was not recorded. This may highly indicate that a relatively large scale fault exists under the western part of Line 1.

• Journal of the Korean Geophysical Society
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• v.2 no.1
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• pp.45-56
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• 1999

Seismic refracrion and reflection surveys were conducted along an E-W trending track of 482 m long in Ilwall-dong, Pohang. End-on spread was employed as source-receiver configuration with 2 m for both geophone interval and offset. Seismic data were acquired using 24 channels at every shot fired every 2 m along the track. Refraction data were interpreted using equations for multi-horizontal layers. Reflection data were processed in the sequence of trace edit, gain control, CMP sorting, NMO correction, mute, common offset gathering, and filtering to produce a single fold seismic section. There are two layers in shallow subsurface of the study area. Upper layer has the P-wave velocities ranging from 267 to 566 m/s and is interpreted as a layer of unconsolidated sediments. Lower layer has P-wave velocities of 1096-3108 m/s and is interpreted as weathered rock to hard rock. Most of the lower layer classified as soft rock. Upper layer has lateral variations in both P-wave velocity and thickness. The upper layer in the eastern part of the seismic line is 3-5 m thick and has P-wave velocity of 400 m/s in average. The upper layer in the western part is 8-10 m thick and has P-wave velocity of 340 m/s in average. The eastern part is interpreted as unconsolidated beach sand, while the western part is interpreted as infilled soil to develop a construction site. Three fault systems of high angle are imaged in seismic reflection section. It is interpreted that the area between these fault systems are relatively safe. Large buildings should be located in the safe ground condition of no fault and footings should be designed to be in the basement rock of 3-10 m deep below the surface.

• Journal of the Korean Institute of Gas
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• v.2 no.2
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• pp.18-25
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• 1998

According to the requirements of ANSI B3l.8, the pipe thickness is determined with hoop stress resulted from internal pressure. And the other loads induced by soil, vehicle, thermal expansion, ground subsidence, etc shall be evaluated rationally. There are two ways of calculating stress of buried gas pipeline. The first is FEM. FEM can calculate the stress regardless of the complexity of pipeline shape and boundary conditions. But it needs high cost and long time. The second is the way to use equation. The reliable equations to calculate the stress of buried gas pipeline was developed and have been used in designing pipeline and evaluating pipeline safety, But these equation are very difficult to understand and use for non-specialist. For easy calculation of non-specialist, the new computer program to calculate stress of buried natural gas pipeline have been developed. The stress is calculated by the equations and extrapolation of the graph resulted from FEM. The full paper is consist of series I and II. In this paper, series I, the calculating equation of the program is explained in detail.

• The Korean Journal of Quaternary Research
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• v.18 no.1 s.22
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• pp.1-20
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• 2004

A geoscientific research was performed on 12 samples of comb-pattern potteries which were excavated at Daecheonri neolithic site, Korea. The texture and compositions of 12 potteries and surrounding metrix of soil and rocks were compared with the help of petrographic microscope, XRD and REE data. As to the manufacturing techniques thick potteries are caused by the amount and number of coarse grains which are assumed to be added shards when their distributional pattern are considered. DC1, DC3, DC 7 and DC11 samples have clearly oriented textures, and the orientation of vesicles in DC3 and DC11 samples arranged in the same direction with those on the pottery surface. This indicates the use potter's wheel technique in manufacturing potteries. Burning temperature is assumed over $800^{/circ}C$, particularly under reduction environment. As to the source, raw materials of pottery matrix are derived from the bottom of excavation site, or in an extracted outcrop of the northwestern foothill from site, while the shard materials are very similar with those extracted from sandy loams near sites. Finally any use pattern of pottery may control the pottery thickness, shard addition, and matrix selection.