• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.5
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• pp.123-128
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• 2015

This study conducted a series of field experiments using soil conditioners, Polyacrylamide(PAM) and gypsum, to evaluate their effects in reducing sediment loss and surface runoff. In addition, the correction factors (K-alpha) for the erodibility factor (K) were determined to reflect the effects of PAM and PAM+gypsum in applying the USLE equation. Experimental erosion plots individually sized $10m^2$ (5 m long, 2 m wide and 1 m deep) have different slopes (10, 20 and 30%). Erosion plots were prepared for one control (C; no PAM and gypsum) and two treatments (P; PAM 20 kg/ha, PG; PAM 20 kg/ha+gypsum 3,000 kg/ha). The amounts of soil eroded and runoff were continuously monitored from July $1^{st}$ to Oct. $31^{st}$ in 2010 and compared to each other. The amount of sediment loss from a control plot was 399.2 ton/ha and the relative reduction of sediment loss were 11.4% and 33.4% for PAM-treated and PAM+gypsum treated plots, respectively. This study also determined the K-alpha factors in the USLE equation to account for the erosion control effectiveness of PAM and gypsum application. The K-alpha factors were calculated as 0.92 for PAM-treated plot and 0.69 for PAM+gypsum-treated plot. The findings of this study revealed that soil conditioners (PAM and gypsum) could play a significant role in controlling soil erosion. In addition, the modified USLE equation using the K-alpha could provide valuable information to make better decision on establishment of best management practice for soil erosion control in agriculture.

• Journal of Mushroom
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• v.11 no.4
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• pp.292-296
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• 2013

Recently, Pleurotus eryngii, King oyster mushroom is the main export item in South Korea mushroom industry. For appropriate transportation to Europe and USA markets, it is necessary to elucidate suitable conditions of storage and treatment of post-harvest during long time shipping. Whole mushrooms were packed with polypropylene anti-fog film (30 um) without trimming. The range of package weight and oxygen permeability of film were 200 g~400 g and 2000~5000 $cc/m^2$, 24 h,atm, respectively. The weight loss ratio was increased with increasing storage time. There were no big differences in weight loss ratio according to package weight and oxygen permeability of film at low temperature storage($4^{\circ}C$). In case of package weight is 400 g and oxygen permeability of film is 3000 $cc/m^2$, 24 h, atm. As a results of freshness, the optimum packing weight and oxygen permeability of film of P. eryngii were 400 g and below 2,000 $cc/m^2$, 24 h, atm, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.431-432
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• 2012

In the era of 20 nm scaled semiconductor volume manufacturing, Microelectronics Manufacturing Engineering Education is presented in this paper. The purpose of microelectronic engineering education is to educate engineers to work in the semiconductor industry; it is therefore should be considered even before than technology development. Three Microelectronics Manufacturing Engineering related courses are introduced, and how undergraduate students acquired hands-on experience on Microelectronics fabrication and manufacturing. Conventionally employed wire bonding was recognized as not only an additional parasitic source in high-frequency mobile applications due to the increased inductance caused from the wiring loop, but also a huddle for minimizing IC packaging footprint. To alleviate the concerns, chip bumping technologies such as flip chip bumping and pillar bumping have been suggested as promising chip assembly methods to provide high-density interconnects and lower signal propagation delay [1,2]. Aluminum as metal interconnecting material over the decades in integrated circuits (ICs) manufacturing has been rapidly replaced with copper in majority IC products. A single copper metal layer with various test patterns of lines and vias and $400{\mu}m$ by $400{\mu}m$ interconnected pads are formed. Mask M1 allows metal interconnection patterns on 4" wafers with AZ1512 positive tone photoresist, and Cu/TiN/Ti layers are wet etched in two steps. We employed WPR, a thick patternable negative photoresist, manufactured by JSR Corp., which is specifically developed as dielectric material for multi- chip packaging (MCP) and package-on-package (PoP). Spin-coating at 1,000 rpm, i-line UV exposure, and 1 hour curing at $110^{\circ}C$ allows about $25{\mu}m$ thick passivation layer before performing wafer level soldering. Conventional Si3N4 passivation between Cu and WPR layer using plasma CVD can be an optional. To practice the board level flip chip assembly, individual students draw their own fan-outs of 40 rectangle pads using Eagle CAD, a free PCB artwork EDA. Individuals then transfer the test circuitry on a blank CCFL board followed by Cu etching and solder mask processes. Negative dry film resist (DFR), Accimage$^{(R)}$, manufactured by Kolon Industries, Inc., was used for solder resist for ball grid array (BGA). We demonstrated how Microelectronics Manufacturing Engineering education has been performed by presenting brief intermediate by-product from undergraduate and graduate students. Microelectronics Manufacturing Engineering, once again, is to educating engineers to actively work in the area of semiconductor manufacturing. Through one semester senior level hands-on laboratory course, participating students will have clearer understanding on microelectronics manufacturing and realized the importance of manufacturing yield in practice.

• Journal of Fashion Business
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• v.9 no.4
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• pp.59-78
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• 2005

This study aims to know the deferences of hair fashion feeling group in accordance with hair styling activities, general characteristics, life styles objecting to capital area university women students and aid to hair fashion design. So the results are as belows. 1. Frequency Analysis of Categories A. Hair fashion feeling - Natural, sexy, romantic pretty, sophisticate, ethnic are 90% in total hair fashion feeling variables in sequence of frequency, so it can be said these are in vogue. B. Hair styling activities - The objections visit the hair salon once 1-2months, spend about 42,000 won a month, perform cut & wave perm to sentimental reasens & hair style changes, determine the hair style well coordinated in her image and managed easily. In her home, they manage her hair style 12 minutes a day, spend 17,000 won to buy hair aids, do hair blow dry or pin or pony tail mainly in the morning, scarcely use the hair styling aids but if use, essence or wax mainly. And the degree of interest to hair style is high. C. General Characteristics - The objections's average age is 21.1, residence is seoul kangnam 23.3%, seoul kangbook 18.4%, other capital areas 58.4%, the degree of education is university students 94.9%, graduated student 5.1%, marriage is married 96%, unmarried 2.8%, family who live with is married are mainly man & woman and living with father & mother in low in man's, unmarried are mainly live alone & nuclear family, personal expenses a month is 300,000 won in average, income of home is 4,000,000 won a month. D. Life style - The objections are not in interest of physical exercises but if are, do yoga & health, like drama & comedies program, watch TV or meet friend in leisure time, like balad & dance music, fashion magazine, meet friend in cafe or college. 2. Relationship of hair fashion feeling & other variables Using the $x^2$-test, level p<0.05, Hair styling activities(frequency of hair salon coming in and out, ordinary time representing hair style, preferred hair styling aids, the amount of hair style interest), General Characteristics(age), Life style(leisure time) variables are meaningful.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.2 no.1
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• pp.77-79
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• 2002

The urea cycle, consisting of a series of six enzymatic reactions, plays key roles to prevent the accumulation of toxic nitrogenous compound and synthesize arginine de novo. Five well characterized diseases have been described, resulting from an enzymatic defect in the biosynthesis of one of the normally expressed enzyme. This presentation will focus on two representative diseases; ornithine transcarbamylase(OTC) deficiency and citrullinemia(argininosuccinate synthetase deficiency). OTC deficiency is one of the most common inborn error of urea cycle, which is inherited in X-linked manner. We identified 17 different mutations in 20 unrelated Korean patients with OTC deficiency; L9X, R26P, R26X, T44I, R92X, G100R, R141Q, G195R, M205T, H214Y, D249G, R277W, F281S, 853 del C, R320X, V323M and 10 bp del at nt. 796-805. These mutations occur at well conserved nucleotide sequences across species or CpG hot spot. The L9X and R26X lead to the disruption of leader sequences, required for directing mitochondrial localization of the OTC precursor. Their phenotypes are severe, and neonatal onset. The G100R, R277W and V323M mutations were uniquely identified in patients with late onset OTC deficiency. The other genotypes are associated with neonatal onset. Out of 20 patients with OTC deficiency, only 6 patients are alive; two were liver transplanted, and normal in growth and development at 2, 4 years after transplantation respectively. Citrullinemia is an autosomal recessive disease, caused by the mutations in the argininosuccinate synthetase(ASS) gene. We identified in 3 major mutations in 11 unrelated Korean patients with citrullinemia; G324S, $IVS6^{-2}$ A to G, and 67 bp ins at nt 1125-1126. Among these, the 67 base pair insertion mutation is novel. The allele frequency of each mutation is; G324S(45%), IVS6-2 A to G(32%), and 67 base pair insertion(14%). All patients are diagnosed at neonatal or infantile age. Interestingly, two patients presented with stroke like episode. Out of 11 patients, 5 patients died. Among 6 patients alive, one patient was successfully liver transplanted.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.124-128
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• 1995

The present study was conducted to elucidate nitrite scavenger derived from seeds of Cassia tora L. Methanolic extract of Cassia tora L was refractionated into ethyl ether, chloroform, ethyl acetate and water farction, and nitrite scavenging abilities of these fractions were investigated. Among these fractions, ethyl acetate fraction had the strongest nitrite scavenging ability(97%/2 mg). Therefore, to further investigate nitrite scavenger, ethyl acetate fraction was fractionated by silica gel column chromatography with a chloroform-methanol($10:0{\sim}0:10$) and then compound A and B were isolated. Compound A had a stronger nitrite-scavenging effect than compound B. Therefore the further separation of compound A was carried out by HPLC(32% acetonitrile. 1 ml/min) using ${\mu}Bondapak$C18 column$(3.9{\times}300 mm)$ and finally compound A-1 was obtained from compound A. Compound A-1 had by far nitrite-scavenging ability as compared with that of ascorbic acid. Compound A-1 was identified as $nor-rubrofusarin-6-{\beta}-mono-D-glucoside$ from the profiles of UV, IR and $^1H-NMR$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.440-443
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• 2002

Present1y the X-Ray diagnosis system is a real condition that is changing by digital ways in it's existent analog ways. This digital radiation detector is divided by the direct method and the indirect method. The indirect method of applied voltage has special qualities that the resolution is low than direct method by diffusion effect that happens. The conversion process ( radiation${\rightarrow}$visible ray${\rightarrow}$electrical signal of two times, has shortcomings that the energy conversion efficiency of electrical signal is low. The direct method has shortcomings that need strong electric fie1d to detect electrical signal efficiently. This research achieved to develop digital detector of the Hybrid method that have form that mixes two ways to supplement shortcoming of direct. indirect method. A studied electrical characteristic by Iodine's Mixture ratio change is added to selenium in the detector which has a multi-layer structure (Oxybromide + a-Se). There are 8 kinds of Manufactured compositions to amorphous selenium Iodine each 30ppm, 100ppm, 200 ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm by a doped photoconductor through a vacuum thermal evaporation method. The phosphor layer is consisted of Oxybromide ($BrO_2$) which uses optical adhesives multi-layer structure. The manufactured compositions calculates and compares Net Charge and signal to noise ratio measuring Photocurrent about Darkcurrent and X-ray. When doped Iodine Mixture ratio is 500ppm to the multi-layer structure (Oxybromide + a-Se), applied voltage of $3V/{\mu}m$, leakage current of compositions $2.61nA/cm^2$ and net charge value by 764pC/$cm^2$/mR then the best result appeared.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.1
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• pp.40-45
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• 2015

Electrode systems: a protrusion on conductor (POC), a protrusion on enclosure (POE), a crack in epoxy plate and a free particle (FP) were fabricated to simulate insulation defects in a gas insulated switchgear (GIS). $SF_6$ gas was filled in the electrode systems by 3 bar and/or 5 bar, respectively. Partial discharge (PD) pulses were detected through a $50{\Omega}$ non-inductive resistor. A calibration test was carried out according to IEC 60270, and the sensitivity was 0.25 pC/mV. PD pulses were distributed in the phase of $50^{\circ}{\sim}135^{\circ}$ and over 95% of them existed in the phase of $55^{\circ}{\sim}120^{\circ}$ for the POC. PD pulses were distributed in the phase of $230^{\circ}{\sim}310^{\circ}$ and over 90% of them existed in phase of $220^{\circ}{\sim}300^{\circ}$ for the POE. PD pulses occurred in the phase of $40^{\circ}{\sim}60^{\circ}$ and $220^{\circ}{\sim}300^{\circ}$ for the crack, and pulse counts were 25% higher in negative polarity than in positive polarity. PD pulses were distributed in every phase unlike to other three electrode systems and the peak magnitude was measured at $118^{\circ}$ and $260^{\circ}$ for the FP. As described above, PD pulses were observed in positive polarity for the POC, in negative one for the POE, in both one for the crack and the FP. In conclusion, it is expected that the identification rate of defect type can be improved by considering the polarity ratio of PD pulses on the PRPDA method.

• Safety and Health at Work
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• v.6 no.1
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• pp.25-29
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• 2015

Background: Shift work has been associated with occupational stress in health providers and in those working in some industrial companies. The association is not well established in the law enforcement workforce. Our objective was to examine the association between shift work and police work-related stress. Methods: The number of stressful events that occurred in the previous month and year was obtained using the Spielberger Police Stress Survey among 365 police officers aged 27-66 years. Work hours were derived from daily payroll records. A dominant shift (day, afternoon, or night) was defined for each participant as the shift with the largest percentage of total time a participant worked (starting time from 4:00 AM to 11:59 AM, from 12 PM to 7:59 PM, and from 8:00 PM to 3:59 AM for day, afternoon, and night shift, respectively) in the previous month or year. Analysis of variance and covariance were used to examine the number of total and subscale (administrative/professional pressure, physical/psychological danger, or organizational support) stressful events across the shift. Results: During the previous month and year, officers working the afternoon and night shifts reported more stressful events than day shift officers for total stress, administrative/professional pressure, and physical/psychological danger (p < 0.05). These differences were independent of age, sex, race/ethnicity, and police rank. The frequency of these stressful events did not differ significantly between officers working the afternoon and night shifts. Conclusion: Non-day shift workers may be exposed to more stressful events in this cohort. Interventions to reduce or manage police stress that are tailored by shift may be considered.

• Journal of Plant Biology
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• v.2 no.1
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• pp.14-21
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• 1959

The bamboo, one of staples of South-East Asia, has 1, 250 species in 46 Genus throughout the world South-East Asia, it's main habitat, has 1, 180 species, while South America has about 70 species or so. Major places of it's production in Asia are Korea, southern China, Japan, Malay, Ceylon, Formosa, and Philipine, but of these, Korea, southern China, and Japan are the most famous places for their production of excellant bamboo. In Korea, Kyongsang-Namdo and Cholla-Namdo are known as it's home, occupying 80 per cent of the total area of bamboo production in this country. Kyongsang-Pukdo, Cholla-Pukdo, Chungehong-Namdo, and Kangwon-do are also known as it's minor production. The importance of the bamboo can not be ignored, considering it's role in the industrial development of this country; the bamboo-ware is indispensable for the culture of laver which annually secures a considerable amount of foreign money. But it has long been regreted that the home-made bamboo-ware is far from being able to meet the ever increasing demand in quantity and is forced to be imported annually. In the light of the above mentioned fact, much interested; I undertook the task of investigating the bamboo in this country, Primarily concerned in it's kind and distribution, and could draw the following conclusions as the first phase of my investigation: (1). The amount of the bamboo accumulation in this country, compared with that of pre-worldwar II, is reduced as much as 300, 000 fagots(on fagot amounts to 25 pieces), and now the acreage of the bamboo field is 32, 200$\textrm{km}^2$s. (2). At a mountian peak in Kunoe-myon Wando-kun Cholla-Namdo, I found out a new specis. (Shasamorpha chiisanensis NAKAI Forma wan-Ponia H. P. CHONG) (3). The kinds of the autogenous wild bamboo in this country are as follows; a). 8 kinds in Sinoarundinaria. (5 Spp; 2 For; 1 Var) b). 1 kinds in Pieioplastus. (1 Spp) c). 2 kinds in Pseudosasa. (1 Spp; 1Var.) d) 4 kinds in Sasamorpha. (2 Spp; 1 For.; 1 Var.) e). 4 kinds in Sasa. (4 Spp) In total there are nineteen(19) kinds of autogenous wild bamboo in this country. When adding to this thethirty five (35) species which the japanese has transplanted in Kyongsang-Namdo Forestry Expreimental stations, there are in all fifty four (54) spe ies in this country. (4). As for the distribution of the Northern limitation of the bamboo growing, I found that Sinoarundinaria nigra OHWI var, Henonis HONDA can be cultivated as for as Kosongkun, Kangwon-Do, andSinoarundinaria pubescens HONDA as for as Clung Chong Namdo, and Sinoarundinaria reticulata as far as chung Chong-Pukdo.