• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.106-112
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• 2017

This paper presents a mathematical model derived from the upper-bound theorem of concrete plasticity to rationally evaluate the shear friction strength of concrete interfaces with a construction joint. The upper limit of the shear friction strength was formulated from the limit state of concrete crushing failure on the strut-and-tie action along the construction joints to avoid overestimating the shear transfer capacity of a transverse reinforcement with a high clamping force. The present model approach proposed that the cohesion and coefficient of friction of concrete can be set to be $0.27(f_{ck})^{0.65}$ and 0.95, respectively, for rough construction joints and $0.11(f_{ck})^{0.65}$ and 0.64, respectively, for smooth ones, where $f_{ck}$ is the compressive strength of concrete. From the comparisons with 155 data compiled from the available literature, the proposed model gave lower values of standard deviation and coefficient of variation of the ratios between predictions and experiments than AASHTO and fib 2010 equations, indicating that the proposed model has consistent trends with test results, unlike the significant underestimation results of such code equations in evaluating the shear friction strength.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.582-591
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• 2009

The pyramid graph is an interconnection network topology based on regular square mesh and tree structures. In this paper, we adopt a strategy of classification into two disjoint groups of edges in regular square mesh as a base sub-graph constituting of each layer in the pyramid graph. Edge set in the mesh can be divided into two disjoint sub-sets called as NPC(represents candidate edge for neighbor-parent) and SPC(represents candidate edge for shared-parent) whether the parents vertices adjacent to two end vertices of the corresponding edge have a relation of neighbor or shared in the upper layer of pyramid graph. In addition, we also introduce a notion of shrink graph to focus only on the NPC-edges by hiding SPC-edges in the original graph within the shrunk super-vertex on the resulting graph. In this paper, we analyze that the lower and upper bound on the number of NPC-edges in a Hamiltonian cycle constructed on $2^n\times2^n$ mesh is $2^{2n-2}$ and $3*(2^{2n-2}-2^{n-1})$ respectively. By expanding this result into the pyramid graph, we also prove that the maximum number of NPC-edges containable in a Hamiltonian cycle is $4^{n-1}-3*2^{n-1}$-2n+7 in the n-dimensional pyramid.

• Journal of the Korean Society of Costume
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• v.17
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• pp.29-43
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• 1991

Yu was a type of dress worn on the upper part of the body which was commonly used in Northeast Asia. It was originally used by the Northern race for the need of courtesy as well as protecting cold. It was believed that Yu in Northeast Asia, which was called Kaftan, was came from Scythai lived in North Eurasian land around the Black sea. Scythians were the first-formed horse-riding race in the world and their civilization influenced those of far Asiatic sector along the steppe route. As their power expanded, their costume culture transmitted to the East(China, Korea, Japan). The upper garment, Yu, was characterized by the left-sided collars, narrow sleeves belted at the waist to the length of the hip line and the tight trouser on the lower part, which we commonly called HoBok(胡服) style. 1. Yu in Northeast Asia was originated from the Eurasians, Scythian Culture. Being exchanged, active style costumes were widely used among Chinese, Koreans and Japanese throughout centuries' including $4{\sim}8$ century. 2. Chinese Yu had a style of wide-sleeves and right-sided collars. The traditional costumes of Han race are consisted of wide-sleeved Yu on the upper and long-skirt on the lower part of the body. Before the adoptation of HoBok during reign of King Jo Mooryung in 307. B.C., HoBok style had already found in the remains since the Sang period. There were various names among Yu during the Han period. Seup, Sean Eui, Kye, Kyu were one of the styles and several names were meant for collar and sleeves. During $4{\sim}8$ centuries, clothes of right-sided collar were found, superior to that of left-sided and narrow sleeves were widely used both the royal and the humble. Various styles of decoration were seen in Yu around neck, back and sleeves comparing other nations. 3. Yu, in Korea, was typical style of Northern-bound HoBok. Both men and women had similarity in Yu style, narrow sleeves, left-sided collar, belted at the waist and to the length of hip line. Influenced by Han race, in the $4th{\sim}8th$ centuries, dual system of collar was found. But we cannot see major change in Yu and finally was connected to the present. 4. The original design of the Japanese costumes was not similar to that of Northern nomadic hunting race, which was suitable for horse-riding activities. Owing to the climates along the island, we could see various conditions ranging from the cold and to the warm. Influenced by the climates, pulling over the neck(Pancho style) were major design in Japan. As Korea was advanced earlier than Japan, Korean landed Japanese territory showing clothes. So primitive costumes had changes in style. During the $4th{\sim}8th$ period. The Korean mode was found in Haniwa (which was built to make sacrifices to the dead King) and costumes in Jeong Chang Won. Among the costumes in Jeong Chang Won, we put 3 or more costumes to the category of Yu characterizing elements of Korea and Tang period. From the $4th{\sim}8th$ century, China, Korea, Japan fell into the same cultural category, Scythai. Styles in Yu among three nations, we saw little differences, basically along times. Originated from the West Asia, Yu was transmitted to the far East changing Chinese costumes, Koreans melted it into the traditional elements and then influenced Japan.

• Journal of the Mineralogical Society of Korea
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• v.15 no.1
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• pp.1-10
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• 2002

The present study is focused on the granite weathering and soil formation, and the heavy metal contamination in soils in the Onsan industrial area. For profile study, soil sampling was conducted on each depth and experimental analyses have been conducted on those samples. X-ray diffraction analyses show that clay minerals consist mainly of kaolin minerals, vermiculite, and minor illite. Most of kaolin minerals in the lower kiwi of the profile consist of halloysite as confirmed by formamide intercalation, but the content of halloysite decreases gradually toward the surface since it has been transformed to kaolinite in the upper part of the profile. Thermal treatment by heating at $110^{\circ}C,\;300^{\circ}C,\;and\;550^{\circ}C$ shows a diffuse and broad peak the between 10 and $14\;{\AA}$ region in X-ray diffractograms. This suggests the possible existence of the hydroxy-Al interlayerecl vermiculite. Na-citrate extraction method reaconfirms this result showing transition of $14\;{\AA}$ peak to $10\;{\AA}$ In by removing the interlayer materials and restoring the vermiculite to its original state. The occurrence of hydroxy-Al interlayered vermiculite is also supported by soil pH distribution room 3.9 In the lower part to 3.6 in the upper part of the profile. Sequential extraction experiment was conducted to investigate the states of heavy metals in soils. The experiment shows that relatively high amounts of heavy metals are concentrated in the upper part of the profile and that most of them are bound to Fe/Mn oxides and organic matters while less concentration in clay minerals. The result indicates that most of heavy metal pollutants are concentrated in the surface soil and that the low concentrations of heavy metals in clays are mainly due to the low adsorption capacities of clay minerals such as kaolin minerals and hydroxy-Al interlayered vermiculite in acidified soil condition.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.325-337
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• 2002

We examined the contamination of stream water and stream sediments by heavy metal elements with respect to distance from the abandoned Backun Au-Ag-Cu mine. High contents of heavy metals (Pb, Zn, Cu, Cd, Mn, and Fe) and aluminum in the waters connected with mining and associated deposits (dumps, tailings) reduce water quality. In the mining area, Ca and SO$_4$ are predominant cation and anion. The mining water is Ca-SO$_4$ type and is enriched in heavy metals resulted from the weathering of sulfide minerals. This mine drainage water is weakly acid or neutral (pH; 6.5-7.1) because of neutralizing effect by other alkali and alkaline earth elements. The effluent from the mine adit is also weakly acid or neutral, and contains elevated concentrations of most elements due to reactions with ore and gangue minerals in the deposit. The concentration of ions in the Backun mining water is high in the mine adit drainage water and steeply decreased award to down stream. Buffering process can be reasonably considered as a partial natural control of pollution, since the ion concentration becomes lower and the pH value becomes neutralized. In order to evaluate mobility and bioavailability of metals, sequential extraction was used for stream sediments into five operationally defined groups: exchangeable, bound to carbonates, bound to FeMn oxide, bound to organic matter, and residual. The residual fraction was the most abundant pool for Cu(2l-92%), Zn(28-89%) and Pb(23-94%). Almost sediments are low concentrated with Cd(2.7-52.8 mg/kg) than any other elements. But Cd dominate with non stable fraction (68-97%). Upper stream sediments are contaminated with Pb, and down area sediments are enriched with Zn. It is indicate high mobility of Zn and Cd.

• The Korean Journal of Applied Statistics
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• v.20 no.2
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• pp.267-280
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• 2007

Various single-valued design optimality criteria such as D-, G-, and V-optimality are used often in constructing optimal experimental designs for mixture experiments in a constrained region R where lower and upper bound constraints are imposed on the ingredients proportions. Even though they are optimal in the strict sense of particular optimality criterion used, it is known that their performance is unsatisfactory with respect to the prediction capability over a constrained region. (Vining et at., 1993; Khuri et at., 1999) We assume the quadratic polynomial model as the mixture response surface model and are interested in finding efficient designs in the constrained design space for a mixture. In this paper, we make an expanded list of candidate design points by adding interior points to the extreme vertices, edge midpoints, constrained face centroids and the overall centroid. Then, we want to propose a robust design with respect to D-optimality, G-optimality, V-optimality and distance-based U-optimality. Comparing scaled prediction variance quantile plots (SPVQP) of robust designs with that of recommended designs in Khuri et al. (1999) and Vining et al. (1993) in the well-known examples of a four-component fertilizer experiment as well as McLean and Anderson's Railroad Flare Experiment, robust designs turned out to be superior to those recommended designs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.683-688
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• 2018

In this study, we analyzed the heat generation state of a flat heating element by using image processing technology in conjunction with carbon fiber. The flat heating element is manufactured by chopping the carbon fiber to a small size and bonding it again using a dispersing agent. The solution of carbon fiber, bound together using the dispersant, is then filtered onto the nonwoven fabric. The last step is to obtain flat carbon fibers in the form of nonwoven fabrics for the purpose of drying the filtered carbon fibers. In the flat heating element, electricity may be applied to the carbon fiber on the surface produced in this manner. In this study, the flat heating element was analyzed by four methods. The analysis of the heat generation characteristics and heating rate of the flat heating element confirmed that the fabricated sheet heating element corresponds to a normal army. The analysis of the insulation coating and flat heating element module, which can be used for actual product manufacturing, involves two dimensional image analysis using image processing technology. The thermal image analysis of the flat heating element is a programming technique that not only analyzes the heat generation state in both two and three dimensions, but also displays the upper and lower 15 to 20% ranges of temperature corresponding to the heat generation in the image. In the final analysis, it is possible to easily find the erroneous part in the manufacturing process by directly showing the state of the fabricated flat heating element on the screen. By combining this image analysis method of the flat heating element with the existing method, we were able to more accurately analyze the heat generation state.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.5-16
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• 1998

Hwabyung is a common emotional disorder which has symptoms expressed like firt's explosion in middle-aged after long period of emotional suppression among Koreans. It is similar in its characteristics such as neurosis, anxiety, panic attacks in Western Medicine, though the treatment method was not effective. So we have done a clinical research on Oriental Medical Method, especially on Acupuncture Therapy, and obtained following results. 1. Patients with Hwabyung complained of pressure pain around the Chunjung(?中, CV-17) point distinctively. About 70% of those were located on the CV-17 point, 25% were 1cm upper than the CV-17 point and 5% of those were 1cm lower point than the CV-17 point. 2. Degrees of pressure pain were divided into 5 grades from ade 1(feeling pain with slight pressure) to grade 5(feeling no pain with severe pressure), respectively. 3. Patients with Hwabyung showed various symptoms compared to fire's explosion such as anger, chest discomfort, difficulty in breathing. tachycardia. and feeling of epigasfric mass etc., and the degrees were divided into 5 grades according to the severities from grade 1(can't keep their usual living) to grade 5(no complaints with heavy stresses), respectively. 4. For the treatment of Hwabyung in this study, we had given Acupuncture therapy on some points such as Chunjung:?中:CV-17, Jungwan:中脘:CV-12) and Chunchu:天樞:S-25, etc. for 15 minutes a time twice a week. And Bunshimkiumgmnihang(分心氣飮加味方) was administered 3 times a day. 5. About 40% of the patients took treatment for more than 2 months, 29% of those took 1 to 2 months and 31% of those took less than 1 month. In this study, we excluded those who stopped treatment within a month without any expected effects. 6. We evaluated the changes of severity of pain according to the following categories such as - for no change, + for 1 grade, ++ for 2 grades, +++ for 3 grades, and ++++ for 4 grades of improvements. Among the patients taken 1 to 2 months of treatment. 48% of the those showed +, 7% of those showed ++, 3% of those showed +++ and 41% of those showed no change. Among the patients taken less than 2 months of treatment, 20%of those showed +, 40% of those showed ++, 28% of those showed +++ and 13% of those showed no change. 7. We evaluate the changes of symptoms according to the following categories such as - for no change, + for 1 grade, ++ for 2 grades, +++ for 3 grades and +++ for 4 grades of improvements. Among the patients taken 1 to 2 months of treatment, 34% of those showed +, 14% of those showed ++ and 52% of those showed no change. Among the patients taken more than 2 months of treatment, 20% of those showed +, 43% of those showed 20% of those showed +++, 3% of those showed +++ and 15% of those showed no change. 8. When we compare the changes of pain and symptoms according to the periods of treatment, the changes in quantity of pain in 1 to 2 months group was $0.72{\pm}0.75$, in more than 2 months group was $1.83{\pm}0.98$, and the changes in quantity of symptoms in 1 to 2 months group was $0.62{\pm}0.73$, in more than 2 months group was $1.75{\pm}1.03$. According to the above results, we have concluded that more than 2 months of treatment is more beneficial than 1 to 2 months of treatment.

• Journal of Technology Innovation
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• v.25 no.2
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• pp.153-179
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• 2017

Korean government has granted fixed indirect cost rates to several exceptional R&D programs which is lower than the predetermined rate by the government. It has been needed to evaluate the validity of exceptional R&D programs and determine the optimal indirect costs rate of the programs. This study analyzes the cost structure and explores drivers of indirect costs of exceptional R&D programs and evaluates the validity of current indirect costs rates. Finally, we propose the formulas for indirect costs rates of exceptional R&D programs. We analyze the cost structure of the exceptional R&D programs. Equipments and material costs are 50% in infra building program. Scholarship to students is 43% in HRD program. Equipments and material costs are 50% and R&D activity costs are 31% in international R&D program. Main cost components of evaluation program are salary(37%), R&D execution costs(21%) and R&D activity costs(19%). We propose three formulas of indirect costs for exceptional programs. 1) The cost items with exceptionally large amount are excluded in the base of formula for indirect costs. 2) Fixed indirect cost rate is applied for specific R&D programs. 3) Upper bound is set for the cost items with exceptionally large amount in the calculation of indirect costs rate. Our proposal is expected to contribute to the improvement of the efficiency of national R&D programs.