• 제목/요약/키워드: major elements

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발주자 관점의 생산적인 건설 프로젝트와 영향요소의 분석에 관한 연구 - 고속도로 건설사업을 대상으로 - (A Study on Analysis of Productive Construction Project and Influential Elements for Public Owner's Perspective - Focused on Highway Construction -)

  • 우성권;이영환;장철기;이시욱
    • 대한토목학회논문집
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    • 제32권6D호
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    • pp.645-653
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    • 2012
  • 고속도로 건설공사의 경우 기존에 건설된 고속도로에 대한 유지관리비가 증가하고 있어 신규 건설에 필요한 투자비에 대한 효율성의 혁신 및 프로젝트의 품질을 향상시키기 위한 생산성 관리가 필요한 시점이지만, 아직까지 고속도로 건설공사에 대한 생산성 및 성과 측정에 대한 명확한 기준이나 방법, 필요성이 제대로 정립되지 못하고 있는 실정이다. 이에 본 연구는 발주자의 주요 업무인 사업관리 측면에서 생산적 프로젝트의 5가지 주요 구성 요소를 정의하였다. 그리고 생산성에 주요한 영향을 미치는 43개 생산성 영향요소를 정의하고 이들을 세 개의 레벨로 구성된 위계체계로 정의하였다. 또한 고속도로 건설공사의 최대 발주자인 한국도로공사를 대상으로 설문조사를 수행하여 정의된 생산성 영향요소들이 생산적 프로젝트의 달성에 미치는 영향 정도를 파악하고 개선수요 정도를 파악함으로써, 사업의 성공적인 수행을 위하여 중점적으로 관리하여야 할 영향요소를 제시하였다.

평해지역 온정화강암 중 미량원소와 광화작용의 관계에 대한 지화학적 연구 (A Geochemical Study on Trace Elements of the Onjong Granite in Relation to Mineralization, Pyeonghae Area)

  • 이재영;이진국
    • 자원환경지질
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    • 제25권3호
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    • pp.245-258
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    • 1992
  • The variations of certain major and trace elements of the Onjong granite mass was studied on the basis of petrological and geochemical characteristics and compared with those of the Eonyang-Yucheon granite masses in order to investigate the geochemical differences of the granitic rocks in relation to mineralization between Pb-Zn ore district and Pb-Zn-Mo-W ore district in Kyeongsang basin. The Onjong granite mass is classified into granodiorite and monzo-granite, and the Eonyang-Yucheon granite masses into monzo-granite by the Streckeisen's diagram. Between both granite masses there are clear differences in contents of certain major elements and lithophile trace elements. The former have high contents of Ca (2.94%), Mg (1.66%) and Sr (365 ppm), and low contents of K (3.52%), Na (3.51%), Rb (116 ppm), Ba (640 ppm) and Li (18.9 ppm), whereas the latter have high contents of K (4.02%), Na (4.28%), Rb (145 ppm), Ba (695 ppm) and Li (19.3 ppm), and low contents of Ca (1.42%), Mg (0.43%) and Sr (161 ppm). Except for Mo, there are not clear differences in chalcophile trace elements between two granite masses: the Onjong granite mass has higher Mo content (7.1 ppm) lnan that (1.7 ppm) of the Eonyang-Yucheon granite masses, but Pb and Zn contents are similar between the Onjong granite mass (Pb=8.7 ppm, Zn=37.1 ppm) and the Eonyang-Yucheon granite masses (Pb=7.8 ppm, Zn=39.8 ppm). Ca and Sr contents of the Onjong granite mass (Ca> 1.5%, Sr> 270 ppm) are higher than those of the Eonyang- Yucheon granite masses (Ca<1.5%, Sr<270ppm), and Rb/Sr, Rb-Rb/Sr and K-Rb/Sr ratios are clearly distinguishable between the Onjong granite mass(Rb/Sr<0.51, Rb-Rb/Sr>250 and K-Rb/Sr>5.2) and the Eonyang- Yucheon granite masses (Rb/Sr>0.51, Rb-Rb/Sr<250 and K-Rb/Sr<5.0). Thus, variations of certain major and trace elements and ratios are applicable as geochemical index to distinguish the types of mineralization of the ore districts related to the Cretaceous granitic rocks in the Kyeongsang basin.

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진동화강암 및 유천-언양화강암의 광화작용에 관한 지화학적 연구 (A Geochemical Study on the Chindong and Yucbeon - Eonyang Granites in Relation to Mineralization)

  • 이재영
    • 자원환경지질
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    • 제22권1호
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    • pp.21-34
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    • 1989
  • Chindong granites are classified into granodiorite, tonalite and quartz-diorite, and Yucheon - Eonyang granites into monzo-granite by the Streckeisen diagram. These granitic rocks of Cretaceous age show trend of calc-alkaline magma, and the magmatic evolution from basic to acidic rocks is consistant with the general crystallization path of the Cretaceous granitic rocks in the Gyeongsang basin. On the basis of petrological and petrochemical data, variation of major elements (K, Na, Ca, Mg) and trace elements (Rb, Sr, Ba) including ore metals (Cu, Pb, Zn) in the Cretaceous granitic rocks were studied in detail in order to investigate geochemical difference of the granitic rocks in relation to mineralization between Cu province and Pb-Zn province in the Gyeongsang basin. There is clear difference in content of the major elements between Chindong granites and Yucheon-Eonyang granites : Chindong granites have low content of K (1.62%) and Na (2.53%), and high content of Ca (3.75%) and Mg (1.42%) whereas Yucheon-Eonyang granites have high content of K (3.56-3.60%), and low content of Ca (0.96-0.26%) and Mg (0.26-0.21%). There is also clear difference in content of trace lithophile elements between Chindong granites and Yucheon-Eonyang, granites : Chindong granites have low content of Rb (86ppm) and Ba (330ppm), and high content of Sr (405ppm) while Yucheon-Eonyang, granites have high content of Rb (144-161ppm) and Ba (983-1030ppm), and low content of Sr (157-136ppm). The lithophile trace elements of Rb and Sr vary with close relationship to major elements of K and Ca, respectively. Therefore, Chindong granites are much easily distinguished from Yucheon-Eonyang granites by using relationship of K with Rb and Ca with Sr : K<3%, Rb<100ppm, Ca<2% and Sr>200ppm for Chindong granites, and K>3%, Rb>100ppm, Ca<2%, and Sr<200ppm for Yucheon-Eonyang granites. There is not clear difference in content of trace ore metals between Chindong granites and Yucheon-Eonyang granites : Chindong granites of the Cu province have low Cu content (15ppm) which is nearly equal to 13-14ppm of Yucheon-Eonyang granites of the Pb-Zn province, and Yucheon-Eonyang granites have Pb content (29-27ppm) which is rather lower than 37ppm of Chindong granites. But Cu is anomalously high in the mineralized part of Chindong granites in Gunbuk-Haman area, and Zn is apparently higher in Yucheon-Eonyang granites (51-37ppm) than in Chindong granites (29ppm). K/Pb ratio is also c1early distinguishable between Chindong granites (<850) and Yucheon-Eonyang granites (>850). Thus, it may be possible to apply geochemical difference of the granites to distinguish whether a Cretaceous granitic body is Cu related rock or Pb-Zn related rock, and whether it belongs to Cu province or Pb-Zn province in the Gyeongsang basin.

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The Role of Cytoskeletal Elements in Shaping Bacterial Cells

  • Cho, Hongbaek
    • Journal of Microbiology and Biotechnology
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    • 제25권3호
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    • pp.307-316
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    • 2015
  • Beginning from the recognition of FtsZ as a bacterial tubulin homolog in the early 1990s, many bacterial cytoskeletal elements have been identified, including homologs to the major eukaryotic cytoskeletal elements (tubulin, actin, and intermediate filament) and the elements unique in prokaryotes (ParA/MinD family and bactofilins). The discovery and functional characterization of the bacterial cytoskeleton have revolutionized our understanding of bacterial cells, revealing their elaborate and dynamic subcellular organization. As in eukaryotic systems, the bacterial cytoskeleton participates in cell division, cell morphogenesis, DNA segregation, and other important cellular processes. However, in accordance with the vast difference between bacterial and eukaryotic cells, many bacterial cytoskeletal proteins play distinct roles from their eukaryotic counterparts; for example, control of cell wall synthesis for cell division and morphogenesis. This review is aimed at providing an overview of the bacterial cytoskeleton, and discussing the roles and assembly dynamics of bacterial cytoskeletal proteins in more detail in relation to their most widely conserved functions, DNA segregation and coordination of cell wall synthesis.

반경방향 순응기구를 갖는 스크롤 압축기의 동적 거동 (Dynamic behavior of a scroll compressor with radial compliance device)

  • 김현진;김재호;이진갑
    • 설비공학논문집
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    • 제10권1호
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    • pp.33-43
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    • 1998
  • Dynamic behavior of a scroll compressor has been investigated analytically. The equations of motion of moving elements of the scroll compressor such as the orbiting scroll, anti-rotation device, slider bush, and the crank shaft with eccentric crank pin have been set up. As the solutions of these equations, reaction forces between the moving elements, and also between the moving elements and the compressor frame have been calculated. The reaction forces from the moving elements to the frame are the unbalanced forces, which produce accelerations of the compressor body. These accelerations can be used as a measure of the compressor vibration. The major contributions to the unbalanced forces come from the orbiting movement of the orbiting scroll.

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자연채광 요소기술 도출을 위한 창호시스템과 건물요소와의 통합화에 관한 연구 (A Study on Integration of Pre-manufactured Window Systems with Conventional Building Design Elements)

  • 김정태;정인영;정유근
    • KIEAE Journal
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    • 제2권2호
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    • pp.15-22
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    • 2002
  • Importation of mass production of building elements with standardization are vital way for environment-friendly architectural planning, which it makes the lifespan of a building longer than normal with easier maintenance and remodeling. The advantage might be magnified here in Korea since typical types of apartment house are dominated in our construction market. For the purpose, a series of pre-manufactured window systems is one of the optimal elements to be prototype building modules. In the design process of the system windows, lots of consideration should be involved and they include aesthetics, thermal performance, noise reduction, airtightness, and so forth. A real survey on the ready-made window systems has been performed and its optical issue related to luminous peculiarity is what is of major interest in this study. In addition, technical review on more advanced window products and their adaptable potential for the integration with fundamental architectural design elements were carried out.

사무용 의자의 물리적 적합도 평가를 위한 휴먼인터페이스요소 개발 (A Study on Human Interface Elements for Evaluation of Office Chair)

  • 박수찬;김진호;신미경;최경주;이영신
    • 한국가구학회지
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    • 제10권2호
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    • pp.9-16
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    • 1999
  • The goal of the present study is to develop the Human Interface Elements(HIE's) for evaluating the physical suitability of office chairs. HIE is generally defined as the physical characteristic of manufacturing goods, and it is closely related to the body dimension of a user and environment that it is used. In the present study the design elements of a chair were investigated, and from here, HIE's of office chair were developed based on relatedness of the design components, the physical characteristics of users, and characteristics of an environment that it used. As a result, components of a chair were classified as 6 major parts: Seat pan, back rest, arm rest, function control unit, seat supports and whole system. 43 HIE's were extracted from there 6 components. Also, the method for measuring HIE were developed.

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모르터 충전 강관 슬리브를 이용한 철근 이음의 해석 모델 (The Analytical Model for the Reinforcement Bar Connection in Grout-Filled Steel Pipe Sleeve)

  • 황재호;이용재;이원호;이리형
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.519-526
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    • 1997
  • The purpose of this study is to develop the analytical model for the reinforcement bar connection in group-filled steel pipe sleeve, which consists of beam elements for the reinforcement bar and shell elements for the sleeve and the mortar and spring elements for the bond stress-slip relationship. In the reinforcement bar connection using grout-filled steel pipe sleeve, the major variables are the bond stiffness between reinforcement bar and mortar($K_1$) and between sleeve and mortar($K_2$). It is nearly difficult to predict the exact bond stiffness with the experimental results. Therefore, The linearly elastic analyses using ABAQUS, FEM package show the validity of the mathematical equations for the bond stiffness and the choice of material elements in this paper. To predict the behaviour between yield and ultimate tensile strength, the nonlinear analyses must be performed henceforth.

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노인층을 고려한 범용디자인 휴대폰 설계를 위한 사용성 분석 (Usability Analysis for Designing Mobile Phones Based on Universal Design for the Elderly)

  • 임장빈;박민용
    • 대한인간공학회지
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    • 제24권1호
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    • pp.47-53
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    • 2005
  • The purpose of this study was to evaluate performance and subjective satisfaction of mobile phone's interface elements considering the elderly users. First, mobile phone's interface elements were outlined recent foreign and domestic studies. Then, final three mobile phone's interface elements were determined by expert rating, AHP analysis, and questionnaire analysis. Objective and subjective measures were then used to determine the effects of several specific design parameters and aging differences on performance of mobile phones. In this experiment, 38 subjects and 4 independent variables were used to measure task completion time and user's subjective satisfaction. The statistical analyses indicated significant aging differences between older people and younger people in terms of keypad type and bell sound level in performance. Significant aging differences were also found for user subjective satisfaction. It is suggested that some major results from this study be used to develop mobile phone design guidelines that are more usable and accessible for most users, particularly for older users.

주거환경 구성요소에 대한 거주자들의 태도에 관한 연구 (Residents' Attitudes for the components of Home Environment)

  • 조성희;강혜경
    • 한국주거학회논문집
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    • 제11권1호
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    • pp.45-56
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    • 2000
  • This study is to find out the residents' attitudes for the components of home environment. This study proceeded with purposes 1) to define the components which are used to evaluate home environment and 2) to suggest the profile of home environment by analyzing the rate of significance and consideration for them. A survey was conducted by 511 housewives who live in Pusan, and analyzed by using frequency, percentage, mean, factor analysis, t-test, one-way ANOVA and Scheffe's test. The major findings are as follows: 1) The 16 elements were selected as the components which are used to evaluate home environment. 2) As for residents' attitudes, the profile of the rate of significance and consideration for the components showed generally high as over 3.0(mean) in all elements. 3) A comfortable environments, safety, housing atmosphere, traffic environments and educational environments were found out as elements that were very significantly recognized and considered in the profile. 4) As for residents' attitudes according to housing and household characteristics, there was a difference in a few elements.

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