• Title/Summary/Keyword: Wa

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Micro-Pattern Machining Characteristics Evaluation of $Si_3N_4$-hBN based Machinable Ceramics Using Powder Blasting Process (파우더 블라스팅에 의한 $Si_3N_4$-hBN계 머시너블 세라믹스의 미세패턴 가공성 평가)

  • 박동삼;조명우;김동우;조원승
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.13 no.2
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    • pp.33-39
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    • 2004
  • Sandblasting has recently been developed into a powder blasting technique for brittle materials. In this study, the machinability of $Si_3N_4$-hBN based machinable ceramics are evaluated for micro - pattern making processes using powder blasting. Material properties of the developed machinable ceramics according to the variation of h-BN contents give a good machinability to the ceramics. The effect of scanning times, the size of patterns and variation of BN contents on the erosion depth of samples without mask and samples with different mask patterns in powder blasting of $Si_3N_4$-hBN ceramics are investigated. The Parameters are the impact angle of $90^{\circ}$, the scanning times of nozzle up to 40, and the stand-off distances of 100mm The widths of masked pattern are 0.1mm 0.5mm and 1mm. The powder used is Alumina particles, WA#600. and the blasting pressure of powder is 0.2MPa. Through required experiments, the results are investigated and analyzed. As the results, the machinability of the developed ceramics increases as the BN contents in the ceramics.

Medical Expenses Structure on Hospitalized Patients of an Oriental Medical University Hospital (한방병원 입원환자의 진료비 구조 분석)

  • 서미경;이석구
    • Health Policy and Management
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    • v.6 no.2
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    • pp.115-130
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    • 1996
  • This study was performed to investigate the practical oriental medical expenses by the use of internal data of an oriental hospital due to the bias of medical insurance program data. The purpose of this study was to describe prevalent diseases of clinical department in the studied hospital, to analyze medical expenses structure and to verify the each cost share ration of expenses on insurer to insuree. Under this purpose, we analyzed actual medical expenses data of 1,611 hospitalized patients of the oriental medical university hospital with 150 beds that can be approached to internal data from Jan. 1, 1994 to Dec. 31, 1994. The major findings are as follows : 1. Upper five of most frequent diseases of admitted patients were Joul-Jung-Pung(55.5%), Yoo-Kak-Tong(7.3%), Yoo-/Tong(7.1%), Gu-An-Wa-Sa(2.7%) and sequale of Joul- Jung-Pung(2.4%) 2. In medical expenses structure, hospital ward fee was 47.1%, medication fee 41.3%, fee for procedure(acupuncture, moxibustion, negative therapy, physical therapy, etc) 11.1% and consultation fee 0.5%. In addition to the cost share ration of insuree & that of insurer was 75:25 respectly.

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A study on the grinding machining of engineering ceramics with high efficiency using "In-process dressing" (연속 드레싱 공정을 도입한 엔지니어링 세라믹스의 고능률적 연삭 가공에 관한 연구)

  • 강재훈;이재경
    • Journal of the korean Society of Automotive Engineers
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    • v.15 no.2
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    • pp.130-143
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    • 1993
  • Engineering ceramics have some excellent properties as the material for the mechanical components. It is, however, very difficult to grind ceramics with high efficiency because of their high strength, hardness and brittleness. In this paper, experiments are carried out to obtain the effect of "In-process dressing" to grind the Engineering ceramics with high efficiency. To save running time for dressing process and obtain restraint effect of diamond grain wear, "In-process dressing" system using WA stick type honing stone is proposed. Representative Engineering ceramics, such as AI$_{2}$O$_{3}$, Si$_{3}$N$_{4}$, are ground with diamond wheel. Also bending strength test is carried out to check upward tendancy of mecahnical properties as the result of machining defact restraint through the grinding machining method using "In-process dressing" process. Some results obtained in this study provide useful information to attain the high efficiency grinding and the high mechanical properties of Engineering ceramics.rties of Engineering ceramics.

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Effect of Cultivar and Tedding Frequency on the Quality of Fall Harvest Oat Hay (품종 및 반전횟수가 추계수확 연맥건초의 사료가치에 미치는 영향)

  • 한건준;김동암
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.16 no.2
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    • pp.169-176
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    • 1996
  • An experiment was carried out to determine the effect of cultivar and tedding frequency on changes of moisture content of oat(Avena sativa L.) hay during field drying and on quality of baled oat hay after storage. The experimental design was a split-plot with the four oat cultivm such as 'Magnum', 'Cayuse', 'West' and 'Murray' as main plots and the two tedding frequencies such as 1 or 3 times a day as subplots in three replications. Moisture content of fresh cut oat cultivar was higher in the order of 'Magnum', 'Cayuse', 'West', and 'Murray' and the moisture content difference among the cultivm was maintained to the final curing day(P< 0.05). Moisture loss from the oat hay during the last 3 curing days was greater with 3 tedding a day than I tedding a day. Temperature of baled oat hay began to rise critically from the 6th day of storage and wa5 highest in 'Magnum' oat cultivar($45.3^{\circ}C$). Total nitrogen and ADIN contents of late maturing oat hay 'Magnum' and 'Cayuse' were higher than those of early maturing 'Murray' and 'West'. Tedding frequency did not influence total nitrogen and ADIN contents. ADF and NDF contents of early maturing oat hay were higher than those of late maturing oat hay. Relative feed value (RFV) of 'Magnum' oat hay was the highest(l06) and classified as Grade 2 in forage quality standard. Quality grade difference between early and late maturing oat cultivan was only 1 or 2.

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Liquefaction Susceptibility of Quay Walls to Earthquake Loadings (지진으로 인한 안벽의 액상화 위험도 평가)

  • 권오순;박우선;윤길림
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.12 no.1
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    • pp.27-38
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    • 2000
  • The collapses and settlement of harbor facilities from earthquakes were known due mostly to liquefaction of reclaimed land. The most harbor quay wa1ls being designed as gravity types in Korea are known susceptible structures to liquefaction because reclaimed land was not treated resistant to earthquake. In this study, liquefaction susceptibility of reclaimed land behind a large quay walls under construction to earthquake was predicted and its stability was analyzed. In addition, liquefaction prediction methods in harbor facilities specification adopted by both Korea and Japan were compared by applying the methods to prediction of liquefaction susceptibility of reclaimed land, respectively.

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Evaluating the Information Access Skills of Students of a College of Education in Ghana

  • Yebowaah, Franklina Adjoa;Owusu-Ansah, Christopher M.
    • Journal of Information Science Theory and Practice
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    • v.8 no.2
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    • pp.45-54
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    • 2020
  • Access to relevant information determines the quality of life of an individual in society and the academe. Academic institutions have established information literacy programmes to enhance students' access to information. With the elevation of colleges of education to tertiary status in Ghana, pre-service teachers are now required to conduct research to improve their reflective thinking in order to be certified. However, the information access skills of students in colleges of education in Ghana are uncertain. This study draws empirical evidence from students in the Nusrat Jahan Ahmadiyya College of Education, Wa, Ghana on their information access skills. Primary data were collected from 303 respondents from the college using a stratified sampling procedure. The data were collected using a questionnaire and analysed using descriptive statistics. The results indicate that information is available to students through different sources such as the Internet, libraries, and contact with friends and authorities. However, students were limited in respect to access to relevant online resources for their academic activities due to inadequate information access skills. Potential solutions are discussed.

Detergency of Triolein in Mixed Burfactant Solutions (혼합 계면활성제용액에서 Triolein의 세척성)

  • 정혜원
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.2
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    • pp.390-397
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    • 1996
  • The effects of the mixture of surfactants on the removal of triolein applied to cotton and polyester fabrics were studied. The sunactants which were usually formulated to the Iriundry detergents, such as sodium dodecyl sulfonate (LAS), sodium lauryl sulfate (AS), $\alpha$-olefin sulfonate (AOS, C=14), sodium laurethoxy sulfate (AES, EO=3) and lauryl ethoxylate (AE, EO=7) were used. Washing was done at 40'C, 60"C, 80'c and the surfactant concentration was 0.05%. Backscattered electron imaging was made to study the location of triolein in the yarns. Triolein was removed easily from polyester than cotton fabrics.01eic acid added triolein wa9 removed greater than triolein only, except in AE solutions. In AE solutions, the removal of triolein was increased as the tremperature went higher and the increasing rate of the removal of triolein only was greater than that of oleic acid added triolein. In the result, more triolein was removed from triolein only than from oleic acid added triolein at 80t When the other surfactant was added to LAS, AES was the best to cotton fabrics, AOS was to polyester fabrics. Triolein was located in the lumen and grooves of the fibers and the deeper interfiber spaces. Triolein did not make thin film arround the cotton fiber in the surface, but polyester fibers. These are the main reason why the removal of triolein was difficult from cotton fabrics.rics.

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Range Detection of Wa/Kwa Parallel Noun Phrase by Alignment method (정렬기법을 활용한 와/과 병렬명사구 범위 결정)

  • Choe, Yong-Seok;Sin, Ji-Ae;Choe, Gi-Seon;Kim, Gi-Tae;Lee, Sang-Tae
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2008.10a
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    • pp.90-93
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    • 2008
  • In natural language, it is common that repetitive constituents in an expression are to be left out and it is necessary to figure out the constituents omitted at analyzing the meaning of the sentence. This paper is on recognition of boundaries of parallel noun phrases by figuring out constituents omitted. Recognition of parallel noun phrases can greatly reduce complexity at the phase of sentence parsing. Moreover, in natural language information retrieval, recognition of noun with modifiers can play an important role in making indexes. We propose an unsupervised probabilistic model that identifies parallel cores as well as boundaries of parallel noun phrases conjoined by a conjunctive particle. It is based on the idea of swapping constituents, utilizing symmetry (two or more identical constituents are repeated) and reversibility (the order of constituents is changeable) in parallel structure. Semantic features of the modifiers around parallel noun phrase, are also used the probabilistic swapping model. The model is language-independent and in this paper presented on parallel noun phrases in Korean language. Experiment shows that our probabilistic model outperforms symmetry-based model and supervised machine learning based approaches.

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Growth Inhibitory Effect of Fermented Kimchi on Food-borne Pathogens

  • Lee, Jong-Kyung;Jung, Da-Wa;Kim, Yun-Ji;Cha, Seong-Kwan;Lee, Myung-Ki;Ahn, Byung-Hak;Kwak, No-Seong;Oh, Se-Wook
    • Food Science and Biotechnology
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    • v.18 no.1
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    • pp.12-17
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    • 2009
  • The effect of kimchi, traditional Korean fermented vegetables, on inactivating food-borne pathogens and the kimchi factors affecting the antimicrobial activity were investigated. More cells of Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella typhimurium were inactivated in the kimchi that had low pH and high titratable acidity. Of the raw ingredients in kimchi, raw garlic showed the strongest antimicrobial activity against the pathogens. When kimchi was fermented at 0, 4, 10, or $20^{\circ}C$ to pH 4.4, higher kimchi fermentation temperature resulted in higher titratable acidity. The greatest inactivation of S. typhimurium occurred in kimchi fermented at $20^{\circ}C$, while L. monocytogenes were inactivated in kimchi fermented at $0^{\circ}C$ in situ. This study showed that appropriately fermented kimchi can inactivate various food-borne pathogens and that the fermentation temperature of the kimchi is an important factor in determining the ability of the kimchi to inactivate specific pathogens. Lactic acid bacteria (LAB) multiplication and organic acids produced according to LAB metabolism play a role in inactivating food-borne pathogens in kimchi.

Isolation and Characterization of Acidic Polysaccharides Activating Complement System from the Hot Water Extracts of Pteridium aquilinum var. latiusculum (고사리 열수 추출물로부터 보체계 활성화 산성 다당의 분리 및 특성)

  • O, Byeong-Mi;Gwon, Mi-Hyang;Na, Gyeong-Su
    • The Korean Journal of Food And Nutrition
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    • v.7 no.3
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    • pp.159-168
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    • 1994
  • From the hot water extract of bracken(Pteridium aquilinum var. latiusculum), a Korean win edible plant, anti-complementary acidic polysaccharides were Isolated. Crude polysaccharide fraction(HPA-1) was obtain ed by methanol reflux, ethanol precipitation, dialysis, and lyophilization. HPA-1 contained 81.80% of total sugar, 30.40% of uronic acid, and 15.60cA of protein. HPA 1 was purified consecutively by cetavlon fractionation and chromatography including ion exchange nth DEAE-Sepharose CL 6B and gel permeation with Sephadex G-100 and Sepharose CL-6B. HPA-2- IVa and HPA-Va-2 were nearly homogeneous on HPLC and had 500,000 and 560,000 daltons of molecular weights, respectively. HPA-2-Wa consisted of fucose, galacturonic acid, and glucuronic acid at the molar ratio of 1.40 : 0.97 : 1.88. HPA-2-Va 2 was composed of rhamnose, galactose, and galacturonic acid at the molar ratio of 1.00 : 1.38 : 1.39. The polysaccharides were found to activate the C3 component both In the presence and In the absence of Ca2+ through the crossed-immunoelectrophoresis suggesting that those Involved in both classical and alternative complement pathway.

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