• The Korea Swine Journal
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• v.17 no.8 s.192
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• pp.88-92
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• 1995

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.1
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• pp.1-8
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• 2011

Spray density of the water spray system which is installed in long road tunnels and hazardous vehicle tunnels is applied without proper performance assessment process. In this study, the requirements of Spray Density Guidelines at the standard pressure is investigated through spray test set up the nozzle of a water spray system in a simulated road tunnel. The results showed that all the nozzles used in the test area did not meet the requirements of the Guidelines. The absence of performance test codes and inspection process on the nozzle at real scale in tunnels may have caused this practice. Therefore, it is suggested that the performance test regulations of the nozzle on the water spray system is established in order to properly assess the system performance.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.358-372
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• 1987

This study was performed to obtain data which can be applied to use of water-proof mortars. The data was based on the properties of water-proof mortars depending upon various mixing ratios to compare those of cement mortar. The water-proof agents used were retard and accelerate type which are being used as mortar structures. The water-proof agents, mixing ratios of cement to fine aggregate were 1:1, 1:2, 1:3 and 1:4. The results obtained were summarised as follows; 1. The results of flow test, water-cement ratio was increased with the increasing of mixing ratio. 2. The permeability were increased in poorer mixing ratio and higher water pressure. 3. The bulk density was decreased with the increasing of mixing ratio, and compressive and tensile strength were increased with increasing of the bulk density. 4. At 1:1 mixing ratio, the highest strengths were showed and strengths were decreased with the increasing of mixing ratio. 5. The absorption rates were increased in- poorer mixing ratio 6. The correlation between W/C, permeability, bulk density, compressive strength and absorption rate were highly significant as a straight line, respectively.

• International Journal of Highway Engineering
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• v.5 no.2 s.16
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• pp.15-24
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• 2003

The performance of waterproofing system (WPS) is known to be a function of many complex interaction of material factors, design details, and the quality of construction, but it is mainly determined by the bond strength, which is measured by tensile adhesive strength (TAS) test. to the concrete bridge deck. In this research, eight waterproofing membranes were selected from commercial market and the tensile adhesive characteristics of the WPS on concrete bridge deck were investigated in view of various factor in asphalt pavement. The factors include type of asphalt mixture, pavement thickness, paving temperature and influence of wheel loading. TAS test of different asphalt pavement types showed that TAS of WPS under SMA (Stone Mastic Asphalt) pavement was greater than that under dense asphalt pavement. TAS of sheet membranes was improved as the compaction temperature of asphalt concrete increase, but TAS of liquid membranes were not. The influence of thickness of pavement val minimal with given laboratory test condition. TAS of sheet membranes after wheel tracking test were in the order of the sites under wheel path (UWP), before wheel tracking (BWT) and nearby wheel path (NWP). Since TAS of the same WPS of UWP was higher than TAS of BWT, wheel loading had function of pressing WPS resulting in higher adhesive strength. But liquid membranes were variable on types. The feature of detached interface after TAS test showed that sheet types were all detached in between deck concrete and WPS, and liquid types were detached in between asphalt pavement and WPS.

• Applied Chemistry for Engineering
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• v.30 no.1
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• pp.39-42
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• 2019

We report on the design of oil-water separators and the selection of materials for the effective application of highly selective membranes fabricated by commercial PET (polyester) fabrics. The waterproof ability of PET fabrics was optimized to improve the separation selectivity. The density of individual PET fabrics should be over $60g/m^2$, and the multi-layered structure is more favorable for the waterproof ability together with maintaining the removal efficiency. For the continuous adsorption and removal process, the rotating perforated cylinder was selected, and covered with membranes. Furthermore, more improved and stable removal efficiency was obtained by installing floating baffles which forces the oil content to move toward membranes.

• Fashion & Textile Research Journal
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• v.21 no.5
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• pp.597-605
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• 2019

This paper examined the garment formability and appearance of perspiration absorption, fast dry, and breathable fabrics. The mechanical properties and seam pucker properties of these fabrics were measured and regression analysis was conducted between fabric structural parameters and their mechanical and seam pucker properties. The superior total appearance value (TAV) of fast dry knitted fabrics for sports-wear was achieved in fabrics with high extensibility and bending rigidity; consequently, it increased with increasing stitch density and tightness factor. The formability of the fast dry knitted fabric also improved with an increasing stitch density and tightness factor. The seam pucker was influenced by bending rigidity and a good seam pucker was exhibited in the fast dry knitted fabrics with low stitch density and tightness factor. However, the formability (F) of the breathable fabric improved by increasing extensibility and bending rigidity that decreased with an increasing cover factor and the thickness of the breathable fabric. In addition, seam pucker deteriorated with an increasing cover factor and the thickness of the breathable fabric, which was similar to the results of the formability predicted in fabric mechanical properties. A superior seam pucker was achieved in fabrics with high extensibility and low bending rigidity.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.1-10
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• 2020

This paper reviews the recent development of electronic textile technology, mainly focusing on chip-textile bonding. Before the chip-textile bonding, a circuit on the textile should be prepared to supply the electrical power and signal to the chip mounted on the fabrics. Either embroidery with conductive yarn or screen-printing with the conductive paste can be applied to implement the circuit on the fabrics depending on the circuit density and resolution. Next, chip-textile bonding can be performed. There are two choices for chip-textile bonding: fixed connection methods such as soldering, ACF/NCA, embroidery, crimping, and secondly removable connection methods like a hook, magnet, zipper. Following the chip-textile bonding process, the chip on the textile is generally encapsulated using PDMS to ensure reliability like water-proof.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.101-110
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• 2009

This study was conducted to investigate the effect of compound fertilizer contained slow release nitrogen such as isobutylidene diurea(IBDU) and methylene urea(MU) on kentucky bluegrasss and the change of nitrogen in the root zone after supplying these at AM turfgrass research institute with soil analysis, chlorophyll content index, leaf area index and dry weight during 6 months from July to December in 2007 year. Fertilizer treatments were designed as following; non-fertilizer(NF), straight fertilizer(CF), methylene urea(MU), isobutylidene diurea(IBDU). The every treatments were arranged a randomized complete block with three replications. Results obtained were summarized as follows: As relative to time after N fertilizers application, ammonium and nitrate in soil were increased, but T-N was decrease. The change of ratio of available Nand T-N by elapsed time after fertilizing was decreased in CF from 30days but increased until 45days. Compared with NF, the turf color index in CF, MU and IBDU was increased 1.5%, 2.5% and 2.3%, respectively, the chlorophyll content 16%, 25% and 26%, the dry weight 31%, 62% and 46% and shoot number 104%, 185% and 148%. The chlorophyll content index of MU and IBDU was increased 7.5% and 8.8% than that of CF, shoot number 40% and 22%, and dry weight 24% and 12% but turf color index was similar to that of CF. These results showed that the MU and IBDU application was supplied nitrogen for a long time in root zone by increasing an available nitrogen, and so promote turf grass growth such as chlorophyll content and shoot number in kentucky bluegrass.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.111-122
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• 2009

Compound fertilizer contained slow release nitrogen was used at golf course management because of promoting turfgrass growth and decreasing fertilizing labor. But, it was hardly published about turf grass growth by its effect and form like isobutylidene diurea(IBDU) and methylene urea(MU) in golf course management of Korea. This study was conducted to investigate the effect of compound fertilizer contained slow release nitrogen such as IBDU and MU on creeping bentgrasss and the change in nitrogen in the root zone after application of fertilizers at AM turfgrass research institute with soil analysis, chlorophyll content index, leaf area index and dry weight during 5 months from July to december in 2007 year. Fertilizer treatments were designed as following; non-fertilizer(NF), straight fertilizer(CF), treatment 1(MU), treatment 2(IBDU 1), and treatment 3(IBDU 2). The every treatments were arranged a randomized complete block design with three replications. Results obtained were summarized as follows: As relative to time after N fertilizers application, ammonium and nitrate in soil were increased, but T-N was decrease. $NO_3$-N and T-N content of slow release fertilizer(SRF), the treatment MU, IBDU 1 and IBDU 2, in soil was higher than that of CF, and the change of ratio of available N and T-N by elapsed time after fertilizing SRFs and CF was higher about 5% in root zone of SF to l5days, but in root zone of SRF from 30days about $5{\sim}10%$. Compared with NF, the turf color index was increased 6.5%, 6.7%, 5.9% and 5.5%, respectively, the chlorophyll content 33.2%, 38.4%, 35.1% and 37.1%, the dry weight 76.2%, 77.7%, 69.5 and 72.3% and shoot number 28%, 52%, 56% and 51%. The chlorophyll content index of MD, IBDU 1 and IBDU 2 was increased $2.6{\sim}5.2%$ than that of CF, shoot number $18{\sim}22%$ but turf color index and dry weight was analogous to that of CF. These results showed that the SRF application was supplied nitrogen for a long time in root zone by increasing an available nitrogen, and so bring turf growth such as chlorophyll content and shoot number in creeping bentgrass.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.77-86
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• 1980

Asking to change the cropping patterns to save the labor and capitals in paddy rice cultivation, the study was intended to know the weed problems under the various possible cultural systems; namely, direct seeding (in broadcast and row), machine transplanting and hand transplanting. Under the conditions as weedy check plots, paddy yields were significantly variated among cropping systems, and the functions of panicle No. and spikelet No. to the yield were neglected, among others. However, the yield and yield components were narrowed among cropping systems, and the function of spikelets number per area was comparatively improved to the others.