• Journal of Welding and Joining
• /
• v.1 no.2
• /
• pp.53-60
• /
• 1983

COD test based on fracture mechanics concept was used in this study to evaluate the fracture toughness quantitatively. Effects of specimen sizes on critical COD value for ABS EH 36 steel and its submerged arc weldments, and the variation of critical COD value depending on metallurgical/mechanical heterogeneities caused by weld thermal cycles were investigated. Experiment was performed by using specimens made from base metal and submerged arc weldments according to BS 5762. Obtained results are summarized as follows; 1) Critical COD value for base metal decreases with increasing thickness of specimen. On hand, as the reduction ratio of critical COD decreases with increasing specimen thickness, critical COD value becomes constant above a thickness of specimen. 2) Critical COD value for weldment decreases with increasing thickness of specimen and was also affected by metallurgical states of base metal. 3) Size effects for weldment was greater at the hardened region. 4) Critical COD value was affected by microstructural change due to weld thermal cycles in weldments; that is, accicular ferrite formation is favorable for increasing of COD value.

• Journal of the Korean institute of surface engineering
• /
• v.27 no.5
• /
• pp.285-291
• /
• 1994

The effects of pulse current parameters on the composition and the microstructure of Pd-Ni alloy electrodeposits were studied. The cathode current efficiency of p.c. electrolysis conditions decreased with increasing both mean and peak current density and was lower than those under D.C. electrolysis condition. Palladium content of Pd-Ni alloy increased with increasing both peak current density and on-time, while it decreased with increasing mean current density and duty cycle. The preferred orientation of Pd-Ni alloys changed with increasing mean current density in the sequence of (111)+(110).(100) or (110)longrightarrow(111)longrightarrow(100) or random distribution of crystal structure. The surface morphology of Pd-Ni alloy changed mainly according to the mean current density and was related to the preferred orientation.

• Elastomers and Composites
• /
• v.26 no.1
• /
• pp.15-22
• /
• 1991

Blends of ethylene-propylene-diene terpolymer(EPDM) and high density polyethylene(HDPE) have been prepared in a roll mill by the process "dynamic curing" where both blending and a crosslinking reaction was carried out simultaneously. As a crosslinking agent, dicumyl peroxide(DCP) was used. Throughout the experimental ranges, the dynamically cured polyblends were shown to be thermoplastic elastomers except highly crosslinked blends of high compositions of EPDM. The increase of melt viscosity was observed as EPDM composition and DCP contents increased. From DSC determinations, the crystallinity decreased with increasing contents of DCP. The tensile strength and elongation at break generally increased with increasing DCP content and increasing HDPE compositions, but highly depended on the combined effects of decreasing crystallinity and increasing crosslinking density.

• Nuclear Engineering and Technology
• /
• v.34 no.1
• /
• pp.90-103
• /
• 2002

The thermal and mechanical properties of compacted bentonite and bentonite-sand mixture were collected from the literatures and compiled. The thermal conductivity of bentonite is found to increase almost linearly with increasing dry density and water content of the bentonite. The specific heat can also be expressed as a function of water ontent, and the coefficient of thermal expansion is almost independent on the dry density. The logarithm of unconfined compressive strength and Young’s modulus of elasticity increase linearly with increasing dry density, and in the case of constant dry density, it can be fitted to a second order polynomial of water content. Also the unconfined compressive strength and Young’s modulus of elasticity of the bentonite-sand mixture decreases with increasing sand content. The Poisson’s ratio remains constant at the dry density higher than 1.6 Mg/m$_3$, and the shear strength increases with increasing dry density.

• Journal of the Korean Dietetic Association
• /
• v.25 no.2
• /
• pp.105-114
• /
• 2019

This study examined the quality characteristics of brown rice Sulgidduk containing acorn powder and the optimal mixing rate (0%, 5%, 10%, and 15%). The moisture contents of brown rice Sulgidduk increased with increasing amount of acorn powder. The DPPH free radical scavenging activities (16.15%~28.06%) and ABTS free radical scavenging activities (22.98%~42.81%) of the brown rice Sulgidduk increased with increasing acorn powder content. The L value of the Hunter's color value decreased with increasing amount of acorn powder. The hardness and chewiness of brown rice Sulgidduk increased with increasing amount of acorn powder. The brown rice Sulgidduk containing 10% acorn powder showed the highest score with regard to the sensory characteristics. These results suggest that the most desirable amount of acorn powder is 10% and the addition of acorn powder could contribute positively toward the quality characteristics of brown rice Sulgidduk.

• International Journal of Internet, Broadcasting and Communication
• /
• v.14 no.4
• /
• pp.148-153
• /
• 2022

In keeping with the fourth industrial revolution, IoT-based environments are being implemented everywhere, and as a result, there is an increasing number of cases in which various types of sensed data are utilized efficiently. In particular, the number of multimedia application cases using smart devices is increasing, and there is an increasing number of cases in which large amounts of data are used as fast and convenient as small amounts of data. Given the increasing size of files used in smart devices, the study designed a modified Htree based on journaling meta data management in Ext4-based smart devices and analyzed performance through experiments of various methods. Performance evaluation analysis using IOZone and Hdread shows that the data size of 100Mbyte compared to the data input / output of existing htree is 10% or more, and that of the super large capacity file of 500Mbyte or more is 5% or more.

• The Korean Journal of Food And Nutrition
• /
• v.34 no.4
• /
• pp.415-422
• /
• 2021

This study assessed the preparation and quality characteristics of cookies prepared from Taraxacum coreamm powder (TCP) (0, 2, 4, 6, 8%) substituting wheat flour. The pH of the cookie dough significantly decreased with increasing TCP. However the density of the cookie dough was not significantly different among the test groups. The baking loss rate of the groups with TCP was slightly lower, whereas the moisture content was higher than the control group. The spread factor of the cookies decreased significantly with increasing TCP. The hardness of the cookies increased as TCP increased. In Hunter's color value, the L and a value of the cookies decreased with increasing TCP, while the b value increased. The DPPH radical scavenging activity of the cookies significantly increased with increasing TCP. Based on the above results, this study suggested that TCP can be a good ingredient to increase the functionality of cookies.

• Journal of the Korean Society of Tobacco Science
• /
• v.3 no.1
• /
• pp.58-65
• /
• 1981

This study was carried out to investigate the influence of distance of planting holes (51, 45, and 40 cm) and number of plants per a hole(4, 5, 6 plants) on agronomic characteristics, yield, and quality of an aromatic tobacco, Sohyang. The results are as follows: 1. Relative light intensity increased by widening the distance of holes. 2. Leaf area per a plant or per a leaf, and leaf length and width increased by widening the distance of holes and decreased by increasing the number of plants per a hole. But L. A. 1. increased by increasing the number of plants per a hole. Leaf shape index (Leaf length/Leaf width) showed little differences among treatments. 3. Dry weight of leaf, root, and stem per a plant decreased by increasing the number of plants per a hole. 4. Total nitrogen decreased by increasing number of plants per a hole and in the case of narrow distance of holes, but nicotine, reducing sugar, ether-extract and ash showed little differences. 5. Yield per 10a decreased by widening the distance of holes. 6. Quality(price per kg) was improved by increasing the number of plants per a hole at the Plot of 51m distance of holes. But there was no variation at the Plot of 45cm. And quality was decreased at the plot of 40cm distance of holes by increasing the number of Plants per a hole. 7. Price per 10a was highest in the plot of which plant spacing was $90\times$40cm and the number of plants per a hole was 4 (11112 plant/10a).

• Membrane Journal
• /
• v.14 no.3
• /
• pp.207-217
• /
• 2004

In this study, we prepared nanofiltration membrane by applying the interfacial polymerization method as a way of manufacturing composite membranes. We have examined the effects of various preparation factors such as monomer concentration and composition, thermal curing condition, post treatment condition. In addition to preparation conditions, we also monitored the effects of operation conditions such as feed solution concentration and operation pressure on the permeation properties of the resulting nanofiltration membrane. We intended to increase the permeation rate of nanofiltration membrane by the enlargement of effective surface area using additives during interfacial polymerization step. With increasing the monomer concentration, membrane permeation rate are decreased with maintaining almost constant rejection. With respect to curing condition, with increasing the curing temperature both permeation rate and rejection are decreased. With increasing the ratio of MPD in amino monomer composition, permeation rate decreased drastically with high rejection. With increasing the feed solution concentration, both permeation rate and rejection decreased. Both permeation rates and rejection increased with increasing the operating pressure. Nanofiltration membrane have higher surface roughness with increasing additive concentration in the case of using MPD contained amine composition than using piperazine alone. Permeation rates are much lower than the nanofiltration membrane prepared by piperazine.

• The Journal of Korean Medicine
• /
• v.23 no.3
• /
• pp.188-199
• /
• 2002

Objectives : Banhasasim-tang has been clinically used to treat upper gastric intestinal discomfort. The object of this study is to examine the defense effect of Banhasasim-tang for acute duodenal injury of the mouse. Methods and Materials : Twenty-one rats were divided into 3 groups and treated as follows: the control group was untreated mice. The ADE group was acute duodenal-damage-elicited mice. The BST group was Banhasasim-tang treated mice before acute duodenal damage elicitation. The groups were examined with common morphology, paneth cells in intestinal crypt, absorptive cells and goblet cells in epithelium, cell division in mucose, COX-l as mucosal protector, COX-2 (which appears to play an important role in inflammation), IL-2R-inducing cellular immuno-chainreaction, and the distribution of apoptotic cells. Results : 1. Common morphology: the ADE group was observed with duodenal injury - loss of villi, infiltration of cells concerned to inflammation (lymphocytes, granular leukocytes) to submucosal layer - by hemorrhagic erosions, while the BST group was seen the same as normal in proportion to increasing treatment time before injury. 2. Histochemical change: the ADE group was observed with noticeable decreased distribution of absorptive cells with microvilli, acid mucin secreted goblet cell, neutral mucin secreted goblet cell, paneth cells compared to the normal group. The BST group was seen to have distribution of epithelium cells resembling normal in proportion to increasing treatment time before injury. 3. Imnunohistochemical change: the ADE group showed a change of factors leading to duodenal injury as reduce of cytokinesis, COX-1, increase of COX-2, IL-2R-. In contrast, the BST group tended to reduction of cytokinesis, COX-1, increase of COX-2, IL-2R- in proportion to increasing taking time before injury. 4. Apoptosis change: the ADE group showed increasing apoptosis cells, in contrast to the BST group which was the same as normal in proportion to increasing treatment time before injury. Conclusions : According to the above results, by increasing the defense system of mucosal epithelium, Banhasasim-tang is thought to effectively protect tissue against ulcers resulting from acute duodenal injury.