• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.99-103
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• 2009

HBr and $O_2$ in $Cl_2$ gas ambient for the high density plasma gate etching has been used to increase the performance of gate electrode in semiconductor devices. When an un-doped amorphous silicon layer was used for a gate electrode material, the notching profile was observed at the outer sidewall foot of the outermost line. This phenomenon can be explained by the electron shading effect: i.e., electrons are captured at the photoresist sidewall while ions pass through the photoresist sidewall and reach the oxide surface at a narrowly spaced pattern during the over etch step. The potential distribution between gate lines deflects the ions trajectory toward the gate sidewall. In this study, an appropriate mechanism was proposed to explain the occurrence of notching in the gate electrode of un-doped amorphous silicon.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1405-1408
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• 2001

Ca salt of soybean oil (PSO) and that of mustard oil plus mahua oil (PMOMO) (50:50) were prepared using double decomposition method, and further tested for their fatty acid composition and degree of saponification. Furthermore, the different levels of protected fat of PSO and PMOMO were evaluated in wheat straw based total mixed ration (TMR) in vitro. Results indicated that capric, lauric, myristic, palmitic, steric, oleic, linoleic, leinolenic acids were traces, traces, traces, 10.00, 2.00, 25.00, 58.50, 5.0% in PSO while the corresponding values in PMOMO were 1.08, 0.28, 0.45, 16.9, 12.95, 44.38, 17.46 and 6.50%, respectively. The degree of saponification of both protected fat supplements was more than 80%. Six treatment combinations were tested I.e., blank without feed and fat supplement (T1); control diet with out fat supplement (T2); control diet plus bypass fat supplement (PSO) so that diet contain 5% fat (T3); control diet plus bypass fat supplement (PSO) so that diet contain 7.5% fat (T4); two more diets viz. T5 and T6 were formulated using bypass fat supplement from PMOMO containing 5 and 7.5% fat respectively. TMR was prepared using 50% concentrate mixture and 50% wheat straw. Result indicated that TVFA, $NH_3-N$,TCA-N, total-N and total gas production were increased in treatment diets at 7.5% level of supplementation, however, fermentation pattern remain similar at 5.0% level of supplementation with respect to control diet. Nevertheless, IVDMD and IVOMD values remained unchanged, rather non-significant at both fat levels and with the both fat sources. On the basis of results it was concluded that Ca-salt of Soybean oil or Mustard plus Mahua oil did not show any negative effect either on digestibility or on microbial protein synthesis in rumen, hence the dietary fat upto 7.5% level in total mixed ration based on wheat straw, could be safely used without any adverse effect on rumen fermentation.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.475-490
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• 2012

Since 1997, Korean Ministry of Knowledge Economy and Ministry of Environment have established data on some 400 basic raw and subsidiary materials and process like energy, petro-chemical, steel, cement, glass, paper, construction materials, transportation, recycling and disposal etc by initiating establishment of LCI database. Regarding agriculture, Rural Development Administration has conducted establishment of LCI database for major farm products like rice, barley, beans, cabbage and radish etc from 2009, and released that they would establish LCI database for 50 items until 2020 later on. The domestic LCI database for seeds, seedling, agrochemical, inorganic, fertilizer and organic fertilizer etc is only at initial stage of establishment, so overseas LCI databases are brought and being used. However, since the domestic and overseas natural environments differ, they fall behind in reliability. Therefore, this study has the purpose to select organic farming materials, survey the production process for various types of organic farming materials and establish LCI database for the effects of greenhouse gas emitted by each crop during the process. As for selecting methods, in this study organic farming materials were selected in the method of direct observation of material and bottom-up method a survey method with focus on the organic farming materials admitted into rice production. For the basic unit of carbon emission amount by the production of 1kg of organic farming material, the software PASS 4.1.1 developed by Korea Accreditation Board under Ministry of Knowledge Economy was used. The study had the goal to ultimately provide basic unit to calculate carbon emission amount in executing many institutions like goal management system and carbon performance display system etc in agricultural sector to be conducted later on. As a result, emission basic units per 1kg of production were calculated to be 0.04968kg-$CO_2$ for oystershells, 0.004692kg-$CO_2$ for expanded rice hull, and 1.029kg-$CO_2$ for bordeaux mixture liquid.

• Journal of Welding and Joining
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• v.33 no.1
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• pp.61-71
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• 2015

The effect of welding condition on microstructure and mechanical property of Plasma-MIG Hybrid Weld between Al 5083 plates(thickness : 10mm) was investigated. 1 pass weld without any defects such as puckering, undercut, and lack of fusion was obtained by 150~200A of plasma current and 5~7mm of welding speed. Gas porosities and shrinkage porosities were existed in the weld near fusion line. As welding speed and plasma current were decreasing, the area fraction of porosity was increasing. The hardness of the weld is increasing as welding speed. On the basis of microstructural analysis, Mg segregated region near dendrite boundaries tends to increase with the welding speed. In the result of hardness test, Distribution of hardness in fusion zone showed little change with the plasma current. However, when the welding speed increased, hardness in weld metal markdly increased. It could be considered that effect of heat input to growth of the dendritic solidification structures. Based on tensile test, tensile properties of weld metal was predominated by area fraction of porosities. Consequently, tensile properties can be controlled by formation site and area fraction of porosity.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.6
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• pp.565-572
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• 2009

This work intends to establish the reliability and fracture toughness $K_{IC}$ criterion of welded joints by EGW for high strength EH36-TMCP ultra thick plate. For this, firstly thermo elasto-plastic analysis has been carried out on two pass X-groove butt joint model to clarify the thermal and mechanical behaviour(residual stress, plastic strain, magnitude of stress and their distribution and production mechanism). Moreover, to establish fracture criterion, analysis of fracture toughness $K_{IC}$ has been performed under the notch machined and residual stress with the load condition on EGW welded joints. A quantitative fracture criterion for EGW welded joints is suggested by using $K_{IC}$.

• Journal of the Society of Disaster Information
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• v.9 no.1
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• pp.22-29
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• 2013

Warm mix asphalt(WMA), which is produced at lower temperatures than hot mix asphalt, has advantages in reductions of fuel consumption and greenhouse-gas emission. In this study, field tests such as skid resistance, rutting(permanent deformation), and roughness were conducted for analysis of long-term field performance of modified warm mix asphalt pavement. Skid resistance after 20 months represents the result similar to initial performance results but rutting and roughness decreased somewhat depending on the period of performance. Measurement results of permanent deformation and roughness could be acceptable because measured pavement location is bus lane that a lot of buses pass and stop. There were no cracks after 11 months, but some minor cracks were observed after 20 months. These results were influenced by increased crack resistance due to fiber addition.

• Journal of Welding and Joining
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• v.31 no.6
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• pp.84-89
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• 2013

The demand of LNG tank and the constituting material, i.e., the Al5083 thick plate, increased due to the rapid growth LNG market. To weld the Al5083 thick plate, the gas metal arc welding (GMAW) of high current is necessary to increase manufacturing productivity incurred by the multi pass welding. However, the arc welding vaporizes the volatile element such as magnesium (Mg). This phenomenon changes the Mg composition of the weld metal and the mechanical properties. The study investigated the weldability of Al5083 alloys after conducting high current GMAW. The Al5083 alloy was welded by using different size of welding wires and high current (800-950A). As the arc current increased from 800A to 950A, the mechanical strength decreased and the secondary dendrite arm spacing (SDAS) increased. Even though the arc current increased SDAS, the mechanical strength decreased due to the Mg loss in the weldment. The large diameter of welding wire decreased the dilution of the weld, therefore increasing the Mg content and the strength of the weld. For the reason, the content of Mg in welds was a major parameter to determine the mechanical property for the high current GMAW. For the arc current between 800A and 950A, the yield strength of the weldments showed a relationship with the weight percent of Mg content ($X_{Mg}$): Y.S = 27.9($X_{Mg}$)-11.

• Neonatal Medicine
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• v.25 no.4
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• pp.186-190
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• 2018

Esophageal atresia (EA) with proximal tracheoesophageal fistula (TEF; gross type B) is a rare defect. Although most patients have long-gap EA, there are still no established surgical guidelines. A premature male infant with symmetric intrauterine growth retardation (birth weight, 1,616 g) was born at 35 weeks and 5 days of gestation. The initial diagnosis was pure EA (gross type A) based on failure to pass an orogastric tube and the absence of stomach gas. A "feed and grow" approach was implemented, with gastrostomy performed on postnatal day 2. A fistula was detected during bronchoscopy for recurrent pneumonia; thus, we confirmed type B EA and performed TEF excision and cervical end esophagostomy. As the infant's stomach volume was insufficient for bolus feeding after reaching a body weight of 2.5 kg, continuous tube feeding was provided through a gastrojejunal tube. On the basis of these findings, esophageal reconstruction with gastric pull-up was performed on postnatal day 141 (infant weight, 4.7 kg), and he was discharged 21 days postoperatively. At 12 months after birth, there was no catch-up growth; however, he is currently receiving a baby food diet without any complications. In patients with EA, bronchoscopy is useful for confirming TEF, whereas for those with long-gap EA with a small stomach volume, esophageal reconstruction with gastric pull-up after continuous feeding through a gastrojejunal tube is worth considering.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.68-75
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• 2022

The breathable film refers to a high-functional film that allows gas and water vapor to pass through very fine and sophisticated pores but not liquid. In this research, the breathable film was prepared based on linear low-density polyethylene (LLDPE) and CaCO₃ particles by extrude method. The LLDPE composite film containing CaCO₃ particles had excellent mechanical properties and functionalties. The drawing is a technologically simple and excellent method for improving the mechanical properties of composite films. In this work, the effects of draw ratio on morphology, crystallinity, pore size distribution, mechanical properties, and water vapor permeability of the films were examined. The results revealed that both surface morphology and breathability were affected by the influence of chain orientation and crystal growth with increasing the draw ratio. The mechanical properties were improved with increasing the draw ratio.

• Applied Chemistry for Engineering
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• v.34 no.6
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• pp.608-612
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• 2023

Nano-diamond (ND) was added during the carbon block preparation process to increase the thermal conductivity of the carbon block. Added ND controlled the generated pore of carbon block due to the volatilization of the binder pitch during the carbonization process. The ND was added to the kneading process of coke and binder pitch, and carbon blocks were prepared by pressing and carbonization. As the amount of added ND increased, the ND ratio of the carbon block increased. The added ND made a pass-way for generated gas by volatilizing the binder pitch during the carbonization process, increasing the density of the carbon block and reducing the porosity. The thermal conductivity of the carbon block was improved by increased density, lowered porosity, and the high thermal conductivity of added ND.