• Title/Summary/Keyword: method of moment

Search Result 3,060, Processing Time 0.04 seconds

Structural Engineering Study of 60M Twin-hull typed Car-ferry (60M급 쌍동형 카페리 구조 엔지니어링 고찰)

  • Lee, Jung-Ho;Kim, In-Chul;Seo, Kwang-Chul
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.23 no.5
    • /
    • pp.532-540
    • /
    • 2017
  • This paper suggests study of basic structure design and structural analysis for the twin car-ferries. The rules and methodology for the strength analysis of medium and small sized high speed vessels with a length of more than 50m and a length/width ratio of more than 12, such as car-ferries, have not been clarified yet. Therefore, in this paper, the members scantling were carried out using the KR Rule, and the car-ferry exclusive vessel standard were further applied to verify the structural strength the design. The scantling of the members is based on the Korea Classification standards, and the car-ferries standards were additionally applied to verify the structural strength of the design. Especially, the ultimate strength of hull girder was additionally carried out by using car-ferry exclusive vessel standard, and proposed to overcome ambiguity of design by existing standard. The results of this study are expected to be useful as basic data related to structural design and structural analysis of high speed twin-hull car-ferries. The present car-ferry design has a sufficient safety margin in strength point of view according to the KR rule.

Suggestion of an Evaluation Chart for Landslide Susceptibility using a Quantification Analysis based on Canonical Correlation (정준상관 기반의 수량화분석에 의한 산사태 취약성 평가기법 제안)

  • Chae, Byung-Gon;Seo, Yong-Seok
    • Economic and Environmental Geology
    • /
    • v.43 no.4
    • /
    • pp.381-391
    • /
    • 2010
  • Probabilistic prediction methods of landslides which have been developed in recent can be reliable with premise of detailed survey and analysis based on deep and special knowledge. However, landslide susceptibility should also be analyzed with some reliable and simple methods by various people such as government officials and engineering geologists who do not have deep statistical knowledge at the moment of hazards. Therefore, this study suggests an evaluation chart of landslide susceptibility with high reliability drawn by accurate statistical approaches, which the chart can be understood easily and utilized for both specialists and non-specialists. The evaluation chart was developed by a quantification method based on canonical correlation analysis using the data of geology, topography, and soil property of landslides in Korea. This study analyzed field data and laboratory test results and determined influential factors and rating values of each factor. The quantification analysis result shows that slope angle has the highest significance among the factors and elevation, permeability coefficient, porosity, lithology, and dry density are important in descending order. Based on the score assigned to each evaluation factor, an evaluation chart of landslide susceptibility was developed with rating values in each class of a factor. It is possible for an analyst to identify susceptibility degree of a landslide by checking each property of an evaluation factor and calculating sum of the rating values. This result can also be used to draw landslide susceptibility maps based on GIS techniques.

The Analysis of Japanese Public Libraries' Characteristics by Types: Focused on the Consideration of Liaison Between Service Contents and Service Space (일본 공립도서관의 유형별 특성 분석 - 서비스내용과 서비스공간의 연계적 고찰을 중심으로 -)

  • Jung, A-Young
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.23 no.2
    • /
    • pp.171-185
    • /
    • 2012
  • This study takes note on the need for the consideration of the relationship between the service contents and service space which libraries provide, since at the moment the demands of library users, purpose of using it, etc. gradually become varied. In this study, type classification of public libraries was done focused on the relationship between service contents and service space, targeting Japanese public libraries. Through linking approach between service contents and service space, the analysis of Japanese public libraries' characteristics and type characteristics could be captured. This study has ultimately aimed to prepare for the basic data which will help Korean public libraries to make connection between service contents and service space in the future. The collected service contents and service space had been analyzed by multi-dimensional data analysis methods such as the "Quantification Theory Analysis Type III" and "Cluster Analysis". After characters of libraries were analyzed, the findings of this study show the views such as "the field of information provided, the method of information provision, and the object of service provision." And types of 44 libraries are classified into those which have 6 kinds of characteristics as follows : (1) group-oriented libraries which provide the jobs and employment information, (2) libraries which provide the jobs and employment information through the counselling space, (3) individual-oriented libraries which provide the information of education-related fields, (4) group-oriented libraries which provide the information of education-related fields, (5) libraries which provide information focusing on the counselling space, (6) individual-oriented libraries which focused on the service provision.

Static Analysis of Actual Bridges for Application of Thin Polymer Concrete Deck Pavements (폴리머 콘크리트 박막 교면포장 적용을 위한 실제 교량 정적 해석)

  • Jeong, Young Do;Kim, Jun Hyung;Lee, Suck Hong;Jeong, Jin Hoon
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.31 no.3D
    • /
    • pp.421-431
    • /
    • 2011
  • In this paper, actual bridges constructed with SMA (Stone Mastic Asphalt) deck pavement and virtual bridges substituted the deck pavement with polymer concrete under the same conditions were statically analyzed to investigate applicability of the thin polymer concrete bridge deck pavements. PSC (prestressed Concrete) girder bridge, steel box girder bridge, PSC box girder bridge, and RC (Reinforced Concrete) rahmen bridge constructed with the SMA deck pavement were analyzed and compared to evaluate various types of the bridge. The bridge deck and pavement were assumed to be fully bonded and the stress and deformation during the construction were ignored while those due to pavement weight and vehicle loading were analyzed. According to the analysis results, the stress and deformation of the bridges using the polymer concrete due to the pavement weight were smaller than those using the SMA because of smaller self weight due to lighter unit weight and thinner thickness of the pavement. The stress and deformation of the bridges using the polymer concrete due to the vehicle loading were larger than those using the SMA because of the smaller area moment of inertia due to the thinner pavement thickness. In case that the pavement weight and vehicle loading applied simultaneously, the stress and deformation of the bridges using the polymer concrete were smaller because effect of self weight reduction was more dominant. Investigation of performance of the bridge deck pavement and analysis of economical efficiency are warranted.

Learning Wind Speed Forecast Model based on Numeric Prediction Algorithm (수치 예측 알고리즘 기반의 풍속 예보 모델 학습)

  • Kim, Se-Young;Kim, Jeong-Min;Ryu, Kwang-Ryel
    • Journal of the Korea Society of Computer and Information
    • /
    • v.20 no.3
    • /
    • pp.19-27
    • /
    • 2015
  • Technologies of wind power generation for development of alternative energy technology have been accumulated over the past 20 years. Wind power generation is environmentally friendly and economical because it uses the wind blowing in nature as energy resource. In order to operate wind power generation efficiently, it is necessary to accurately predict wind speed changing every moment in nature. It is important not only averagely how well to predict wind speed but also to minimize the largest absolute error between real value and prediction value of wind speed. In terms of generation operating plan, minimizing the largest absolute error plays an important role for building flexible generation operating plan because the difference between predicting power and real power causes economic loss. In this paper, we propose a method of wind speed prediction using numeric prediction algorithm-based wind speed forecast model made to analyze the wind speed forecast given by the Meteorological Administration and pattern value for considering seasonal property of wind speed as well as changing trend of past wind speed. The wind speed forecast given by the Meteorological Administration is the forecast in respect to comparatively wide area including wind generation farm. But it contributes considerably to make accuracy of wind speed prediction high. Also, the experimental results demonstrate that as the rate of wind is analyzed in more detail, the greater accuracy will be obtained.

Magnetic Properties of Cr-Doped Inverse Spinel Fe3O4 Thin Films (Cr 치환된 역스피넬 Fe3O4 박막의 자기적 특성)

  • Lee, Hee-Jung;Choi, Seung-Li;Lee, Jung-Han;Kim, Kwang-Joo;Choi, Dong-Hyeok;Kim, Chul-Sung
    • Journal of the Korean Magnetics Society
    • /
    • v.17 no.2
    • /
    • pp.51-54
    • /
    • 2007
  • By substituting Cr in inverse-spinel $Fe_3O_4,\;Cr_xFe_{3-x}O_4$ thin film samples were prepared by sol-gel spin-coating method and their structural electronic, and magnetic properties were analyzed. X-ray diffraction indicates that the lattice constant decrease with increasing Cr composition (x). This result can be explained in terms of occupation of octahedral sites by $Cr^{3+}$ ions with smaller ionic radius than that of $Fe^{3+}$ Vibrating sample magnetometry measurements on the samples at room temperature revealed that saturation magnetization ($M_s$) decrease by Cr substitution, explainable by comparing spin magnetic moment among the related transition-metal ions. A decrease of magnetoresistence effect with x was observed, similar to that of $M_s$. The coercivity of the $Cr_xFe_{3-x}O_4$ films was found to increase with x, attributed to the increase of magnetic anisotropy by the existence of octahedral $Cr^{3+}(d^3)$.

An Empirical Study for Model Development Concerning Advance Directive (사전의료지시서(Advance Directives) 모형 개발을 위한 실증 연구)

  • Hong, Seongae
    • 한국노년학
    • /
    • v.30 no.4
    • /
    • pp.1197-1211
    • /
    • 2010
  • This research was concucted to present a model of advance directives(AD) when a patient, who is in consciousness, shows a preference for an end of life care as an act of preparing for an uncertain situation that may arise in the forseeable future. The subjects of the research are 383 doctors/nurese and adults, who live in six cities and provinces, to investigate the status of AD, attitude regarding a meaningless life-prolonging treatment, and moreover, an understanding of and a preference for AD. The research was done by the well-structured questionnaire. Also, SPSS 14.0 is used to analyse the collected data, focused on frequency analysis, avearage and standard deviation, X2 test. As the results of the study, the most of the surveyed doctors/nurese knew DNR orders and AD and a few of them used DNR orders and AD practically. Also, the result shows that there is a negative conception of meaningless life-prolonging treatment among the responents, in addition, most of them agreed upon the idea of introducing AD to Korea, filling it out and making it legally effective. As a method of making AD out, the respondents wanted to use a form that mixed living will with an Power of Attorney in a document. Also, considering the appropriate time, respondents prefered when they are diagnosed with terminal illness. At the moment, the introductory model for AD, which is suitable for the Korean culture and current situation is presented based on the result of this research. In the future, other researches should deal with specific measures that can lead to a social consensus to adopt AD in Korea.

A study on pop art kidult culture (팝아트적 키덜트 문화 연구)

  • Do, Kyung-Eun
    • Journal of Digital Convergence
    • /
    • v.12 no.2
    • /
    • pp.483-493
    • /
    • 2014
  • In a modern society where various kinds of cultures coexist, kidult culture seeking something pleasant and interesting in the adult culture has made an appearance affected by pop art. The goal of this study is to help the kidult culture carrying on the feature of pop art to promise a bright future in the consumer market and to help kidult marketing through the expansion of globalization of kidult culture goods. The first study method was to refer to the theoretical research material like theses or academic journals to analyze the feature of pop art and cultural phenomenon. The second one was to analyze media reports, TV programs, movies, and ads currently in issue about kidult cultures in news, media data, and internet materials to feel the kidult cultural phenomenon at the moment. The result of this study shows that, especially, popularity, vividness, and sense of humor and wit among the features of pop art have a great influence on the kidult culture. As a result, Firstly, We can expect a vitalization in the consumer market through qualitative and quantitative improvement of kidult consumer culture. Secondly, We should make an effort to expand kidult consumer culture by developing various kinds of culture goods for each age groups. Thirdly, Domestic companies should open up an adult consumer market with self-developed character products. Fourthly, We should make an aggressive marketing strategy for kidult culture goods in the world market in the flow of Hallyu.

Steganalysis Based on Image Decomposition for Stego Noise Expansion and Co-occurrence Probability (스테고 잡음 확대를 위한 영상 분해와 동시 발생 확률에 기반한 스테그분석)

  • Park, Tae-Hee;Kim, Jae-Ho;Eom, Il-Kyu
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.49 no.2
    • /
    • pp.94-101
    • /
    • 2012
  • This paper proposes an improved image steganalysis scheme to raise the detection rate of stego images out of cover images. To improve the detection rate of stego image in the steganalysis, tiny variation caused by data hiding should be amplified. For this, we extract feature vectors of cover image and stego image by two steps. First, we separate image into upper 4 bit subimage and lower 4 bit subimage. As a result, stego noise is expanded more than two times. We decompose separated subimages into twelve subbands by applying 3-level Haar wavelet transform and calculate co-occurrence probabilities of two different subbands in the same scale. Since co-occurrence probability of the two wavelet subbands is affected by data hiding, it can be used as a feature to differentiate cover images and stego images. The extracted feature vectors are used as the input to the multilayer perceptron(MLP) classifier to distinguish between cover and stego images. We test the performance of the proposed scheme over various embedding rates by the LSB, S-tool, COX's SS, and F5 embedding method. The proposed scheme outperforms the previous schemes in detection rate to existence of hidden message as well as exactness of discrimination.

Development of the Korean Form of Zung's Self-Rating Depression Scale (한국형 자가평가 우울척도의 개발)

  • Lee, Jung-Hoon
    • Journal of Yeungnam Medical Science
    • /
    • v.12 no.2
    • /
    • pp.292-305
    • /
    • 1995
  • This study was carried out to develop a Korean language version of Zung's self-rating depression scale (SDS). The subjects consisted of 173 males and 161 females drawn from various groups of the general population by a cluster of sampling methods. In order to analyze the data on depression scores, Pearson's product moment correlation coefficient method was carried out, as well as reliability and factor analysis, by the SPSS/PC+ program. The results obtained were as follows: The mean average of the total depression scores were $40.60{\pm}8.66$ for the subjects. Thirty-seven subjects (11.1%) showed high depression scores of 50 or over. Test-retest reliability(coefficient r=0.82, p <0.001), internal consistency(coefficient r=0.84, p <0.001) were satisfactory. Factor analysis using oblique technique rotation yielded five factors. The items of confusion, indecisiveness, decreased libido, diurnal variation, and psychomotor retardation were scored higher by the subjects. The items of suicidal rumination, psychomotor agitation, constipation, irritability, and weight loss were scored lower.

  • PDF