• Title/Summary/Keyword: degree distribution

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Recognition and Purchasing Behavior about Environment-Friendly Agricultural Produce of Housewives (친환경농산물에 대한 주부들의 인식도 및 구매 행동)

  • Kim, Hyo-Chung;Lee, In-Sook;Kim, Mee-Ra
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.6
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    • pp.845-852
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    • 2010
  • This study examined the recognition and purchasing behavior about environment-friendly agricultural produce (EFAP) of housewives in Yeungnam area. The data were collected from 401 housewives by a self-administered questionnaire on April, 2010. Frequencies, t test, chi-square test, and logistic regression analysis were conducted by SPSS Windows V.17.0. The results of the survey were as follows: (1) the purchase group of EFAP showed higher degree of concern about health and recognition about EFAP than the non-purchase group, (2) knowledge scores about EFAP were very low for both the purchase and non-purchase groups, (3) levels of confidence in EFAP in the purchase group were higher than those in the non-purchase group, (4) the purchase group considered high price as the main distribution problem about EFAP, whereas the non-purchase group regarded low trust toward producers, and (5) monthly household income (below 2,000,000 won) and confidence in EFAP were the significant factors affecting EFAP.

Seismic Fragility Functions of a SDOF Nonlinear System with an Energy Dissipation Device (에너지 소산형 감쇠기가 설치된 단자유도 비선형 시스템의 지진취약도 함수)

  • Park, Ji-Hun;Yun, Soo-Yong
    • Journal of the Earthquake Engineering Society of Korea
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    • v.16 no.2
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    • pp.1-13
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    • 2012
  • Seismic fragility functions are derived for probabilistic evaluation of seismic control performance of energy dissipation devices installed in reinforced concrete structures. Displacement-dependent dampers are added to the nonlinear single-degree-of-freedom systems with different natural periods and hysteretic characteristics of which stiffness and strength has uncertainty. Nonlinear time history analysis is conducted for those SDOF systems and the result is processed statistically to obtain seismic fragility functions in the form of log normal distribution. Variation of seismic fragility functions for different parameters of SDOF systems and dampers are investigated and the seismic control performance is assessed probabilistically.

Statistical Analysis of Microhardness Variations in Plasma Sprayed $Cr_3C_2-NiCr$ Coatings

  • Li, Jianfeng;Huang, jingqi;Ding, Chuanxian
    • Journal of the Korean Vacuum Society
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    • v.7 no.s1
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    • pp.171-178
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    • 1998
  • The microstructure and properties of plasma-sprayed coatings depend on a great number of spraying parameters, random factors, which lead to vibration in these spraying parameters, may in some degree influence the microstructure and properties of the coatings. Therefore, the property values appear certain distributions, and the description and comparison of the properties of plasma-sprayed coatings should be performed employing statistical analysis. In this paper, $Cr_3C_2$-Nicr coatings of different thickness were sprayed onto stainless steel using atmosphere plasma system and adopting three kinds of gun translation speeds. Then the microhardness measurements were performed on polished surface of the coatings. Forty readings were taken and statistically analyzed by calculating the characteristic values, estimating and comparing the means, and assessing whether they belonged to the Normal or Weibull Distribution. This study has found that statistical analysis could discriminate influence of spraying parameters and coating design on microhardness of the $Cr_3C_2$-Nicr coatings from random vibration, which showed that the microharness of the $Cr_3C_2$-Nicr coatings were related to gun translation speed coating thickness.

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The Influence of Internet Expectation and Self-efficacy on Internet Addiction among High School Students (인터넷 기대와 자기효능감이 고등학생의 인터넷 중독에 미치는 영향)

  • Oh, Won-Oak
    • Journal of Korean Public Health Nursing
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    • v.19 no.2
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    • pp.339-348
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    • 2005
  • Purpose: This study was conducted to understand the degree of Internet addiction, Internet expectation and self-efficacy and we also wanted to elucidate the factors influencing this addiction among the high school students in Korea. Method: A total of 348 high school students in the Gyeoung-gi, Daegu and Gyeoung-buk area were surveyed in this study. Data collection was conducted through the use of questionnaires. Results: Internet addiction among high school students in Korea was relatively low. In the overall ratio distribution, however, the students who were classified as either addicted or at risk of addiction accounted were a high percentage of the subjects, 31%. A positive or negative relationship was found between internet addiction and the research variables. Multiple regression analysis revealed that the most powerful predictor of Internet addiction was Internet expectations. Conclusion: Using the above results, it would be necessary to develop an Internet addiction prevention program for adolescents. There should be a qualitative study in the future for an in-depth understanding of internet addiction of adolescents.

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Levels of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans in Soil and Pine needle near Industry Complex in Changwon City

  • Kim Sang-Jo;Kim Sung-Yong;Ok Gon
    • Journal of Environmental Science International
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    • v.14 no.7
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    • pp.629-637
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    • 2005
  • Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were investigated in soil and pine needle samples taken from 16 sites of industrial and residential areas in Changwon, Korea to assess their distribution levels and to suggest the influence of industrial activities, PCDDs/DFs levels in the soil samples ranged from 0.57 to 20.79 pg I-TEQ/g dry weight with a mean value of 4.20 pg I-TEQ/g dry weight. PCDDs/DFs levels in the pine needle samples ranged from 0.39 to 8.75 pg I-TEQ/g dry weight with a mean value of 4.09 pg I-TEQ/g dry weight. In both soil and pine needle samples, the PCDDs/DFs concentrations in the industrial area sites were higher than those in the residential area sites. Homologue profiles in pine needle samples showed different patterns compared with soil samples. Based on the results of principal component analysis (PCA), it was confirmed that pine needles reflected a direct influence from local potential sources of PCDDs/DFs, showing a much higher degree of reflection than in soils. Pine needles are very useful as an indicator for monitoring or estimating the contamination of PCDDs/DFs in other areas which have been impacted by point pollution sources.

Design of Plano-Convex Lens Antenna Fed by Microstrip Patch Considering Integration with Microwave Planar Circuits

  • Yu, Seung-Gab;Yeon, Dong-Min;Kim, Yong-Hoon
    • Journal of electromagnetic engineering and science
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    • v.1 no.1
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    • pp.67-72
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    • 2001
  • In this paper, the plano-convex lens antenna fed by a single patch is studied for a microwave remote-traffic monitoring sensor with constraints of small size and low cost. Measurement of an AUT (Antenna Under Test) involves the considerations of a triangular groove for matched layer and metallic shielding effects. A formulation for extracting the parameters of a piano-convex lens antenna, based on geometrical optics, is introduced using Fermat`s principle of the equi-phased ray condition. Teflon ($\varepsilon_{{\gamma}}$/ =2.0) is chosen as a material of a plano-convex lens antenna for adjustment of aberrations on the lens surfaces automatically. A fabricated plano-convex lens shows 3-dB beamwidth of 7.5 degree and side-lobe level of -29 dB with an aperture distribution of the parabolic-squared taper on pedestal. This lens supports easier integration with the planar microwave circuits by using a microstrip single patch as a primary feeder of the lens antenna.feeder of the lens antenna.

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Relationship Among h Value, Membership Function, and Spread in Fuzzy Linear Regression using Shape-preserving Operations

  • Hong, Dug-Hun
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.8 no.4
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    • pp.306-311
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    • 2008
  • Fuzzy regression, a nonparametric method, can be quite useful in estimating the relationships among variables where the available data are very limited and imprecise. It can also serve as a sound methodology that can be applied to a variety of management and engineering problems where variables are interacting in an uncertain, qualitative, and fuzzy way. A close examination of the fuzzy regression algorithm reveals that the resulting possibility distribution of fuzzy parameters, which makes this technique attractive in a fuzzy environment, is dependent upon an h parameter value. The h value, which is between 0 and 1, is referred to as the degree of fit of the estimated fuzzy linear model to the given data, and is subjectively selected by a decision maker (DM) as an input to the model. The selection of a proper value of h is important in fuzzy regression, because it determines the range of the posibility ditributions of the fuzzy parameters. In this paper, we discuss the interdependent relationship among the h value, membership function shape, and the spreads of fuzzy parameters in fuzzy linear regression with fuzzy input-output using shape-preserving operations.

Comparison of Stress, Depression and Suicidal Ideation between Nursing Students and Students of Other Majors (간호대학생과 일반대학생의 스트레스, 우울 및 자살사고 비교)

  • Cha, Sun Kyung;Lee, Eun Mi
    • The Journal of Korean Academic Society of Nursing Education
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    • v.20 no.4
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    • pp.650-658
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    • 2014
  • Purpose: This study compares differences in stress, depression and suicidal ideation between nursing and students of other academic disciplines. Method: Nursing students (n=105) and students of other majors (n=148) were surveyed on the degree of personal stress, depression and suicidal ideation. Participants were recruited from three universities in cities S and C in Korea. Data were collected from May 1 to 20, 2013. Measurement tools were the Revised Life Stress Scale for College Students, Center for Epidemiological Studies-Depression Scale(CES-D), and Scale for Suicide Ideation(SSI). PASW Statistics 18 was used for descriptive analysis, homogeneity test(chi-square distribution) and ANCOVA. Results: The level of stress among nursing students was lower than that of students in other majors. Among the subcategories of stress, however, stress among nursing students arising from the student-faculty relationship was higher than that of their non-nursing counterparts. Conversely, differences in the prevalence of depression were notsignificant between nursing students and non-nursing students. Ultimately, it was revealed that there exists a strong correlation among stress, depression and suicidal idea for nursing students. Conclusion: Developing stress and depression management programs for nursing students is highly recommended.

Properties of PD Pulses accompanying with propagation of Bush-type tree in LDPE (LDPE에서 부시형 전기트리의 성장에 수반되는 부분방전 펄스의 특성)

  • 박영국;강성화;정수현;박철현;임기조
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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    • pp.293-296
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    • 1998
  • Surface electrical conduction in insulator is most important factor to assess the insulation performances of outdoor insulating materials. In this paper, contamination performance of the widely used materials for outdoor insulator - porcelain, EPDM, Silicone rubber - were discussed by measuring properties of average leakage current and scintillation discharge pulses under artificial contamination conditions. The artificial contaminations used were deionized distilled water fog, 0.5wt% NaCl salt fog of light pollution and 2wt% NaCl salt fog of medium pollution. The average leakage current was appeared linearly with applied voltage at dry and clean surface condition. The magnitude of leakage current was almost same at different kinds of samples. In case of deionized distilled water fog, the characteristics of leakage current and applied voltage was most different to that in case of dry and clean condition. In case of salt fog pollution condition, The leakage current was increased above critical voltage. The scintillation discharges were also activated at the level. the leakage current and scintillation discharges were increased with increasing pollution degree. The resistance to pollution properties of silicone rubber appeared excellent among them.

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A Case of Alternative Therapy for obese patient (대체의학(代體醫學)을 이용(利用)한 비만치료(肥滿治療)의 실제(實際))

  • Lee, Seong-Deog;Song, Tae-Won
    • Journal of Haehwa Medicine
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    • v.9 no.1
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    • pp.503-511
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    • 2000
  • This case study was done on a 37 year old female patient at the department for rehabilitation in Bundang Cha Oriental hospital who was treated for 70 days by traditional Acupuncture and Herbal medicine therapy as well as fasting with saengshig(生食), air bath(風浴) and cold-hot-bath(冷溫浴) for skin revitalisation, furthermore by Doinangyo and exercise for improvement of general condition and colon-hydrocleansing. The results are as following: 1. The body weigth was reduced by 14.5kg from 87.4kg to 72.9kg 2. The obesity degree reduced from 159% to 133% 3. The BMI reduced from 33.3 to 27.8 4. The WHR reduced from 0.96 to 0.88 5. The amount of body fat reduced by 7.7kg from 27.2kg to 19.5kg 6. The fat distribution of the abdomen reduced from 0.92 to 0.85 7. The percent body fat was reduced from 31.1% to 26.7 % 8. Except of a mild systemic pruritus the clinical symtoms like kneepain, fatigue, chilling, headache, indigestion, menorrhalaia improved significantly.

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