• 제목/요약/키워드: approximate quantities

검색결과 28건 처리시간 0.023초

사업기획단계에서의 현수교의 물량추정을 위한 모델연구 (Estimation Model for Approximate Construction Quantities of Suspension Bridge in Early Stage)

  • 박원태;천경식
    • 복합신소재구조학회 논문집
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    • 제6권4호
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    • pp.24-29
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    • 2015
  • Bridge construction cost estimates have generally been conducted by using historial unit-price(per meter or square meter). The traditional estimating method based on unit-price references can never completely reflect the specialty of cable supported bridge. In this paper, we have developed the system for supporting the approximate construction cost and the quantity estimation based on 3D model information in the pre-project planning phase of 3-span continuous suspension bridge with 2-pylons. First of all, we'd analyzed the design information (such as structural design report, blueprint and quantity) and the real cost data from the existing suspension bridges and derived the design variables of the bridges. We developed the BIM wizard that generates a suspension bridge model parametrically based on derived design variables. The principle material quantities of suspension bridge are calculated directly from 3-dimensional bridge model built by using the BIM wizard. We have established the system that the construction cost can be estimated more specific than the traditional estimating method.

적과 단감의 이화학적 특성 (Physicochemical Properties of Prepersimmon)

  • 신동주;김광호;성태수;김종현;손규목;황용일
    • 한국식품영양학회지
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    • 제13권5호
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    • pp.440-445
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    • 2000
  • 단감재배농가에서 전량 폐기되는 적과단감을 이용한 가공식품을 개발하기 위한 기초자료를 얻고자 일반성분, 유리당, 유기산, 무기질 및 비타민 등을 분석하였다. 일반성분은 수분이 89.08%로 대부분을 차지하였으며 회분이 0.26%, 조지방이 0.56%, 조단백질이 0.75%이었다. 유리당은 glucose와 fructose가 각각 3.34%, 3.01%로 대부분을 차지하였으며 sucrose는 미량 검출되었다. 유기산은 citric acid, maleic acid, fumalic acid, lactic acid 등이 검출되었으며 그 중 lactic acid가 68.65mg%로 전체 유기산 함량의 79%를 차지하였다. 무기질은 K, P, Na. Ca, Fe, Zn 등이 검출되었으며 그 중 K이 126.l2mg%로 대부분을 차지하였으며 Fe과 Zn은 미량 검출되었다. 비타민 A는 33.95 R.E.로 완숙단감보다 함량이 적었으며 비타민 C는 171.01mg%로 완숙단감에 비해 10배 이상 함유하였으며 비타민 B$_1$과 B$_2$는 소량 검출되었다.

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경사심벽에 관한 실험적 연구 (An Experimental Study on the Seapage Action of the Inclined Core Wall)

  • 신방웅
    • 한국농공학회지
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    • 제16권4호
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    • pp.3585-3593
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    • 1974
  • This thesis a result of theoretical and experimental studies on the shape of seepage line and seepage quantities in various inclined core walls. The value of this determination was examined and compared with the values of calculation acquaired to be based on Fukutas, Jin's and author's approximate equation of the theory. Thus the writer of this paper confirms that the seepage quantity can be decreased by changing the types of the inclined core wall and it's change of the slope.

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A Quantity Prediction Model for Reinforced Concrete and Bricks in Education Facilities Using Regression Analysis

  • Lee, Jong-Kyun;Kim, Boo-Young;Kim, Jang-Young;Kim, Tae-Hui;Son, Kiyoung
    • 한국건축시공학회지
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    • 제13권5호
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    • pp.506-512
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    • 2013
  • Since the amendment of the law on the private sector investment in social infrastructure in January of 2005, the government has been actively promoting Build-Transfer-Lease (BTL) projects. Notably, most new educational facilities have been built as BTL projects. For these facilities, the unit cost per unit area has been applied to predict construction costs. However, since construction costs are mostly managed after the detailed design phase, the costs can be estimated incorrectly. For this reason, cost management is needed in the planning phase, with a sound approximate estimate to prevent the wasteful use of funds. To address this shortcoming, this study aims to develop a quantity prediction model for education facilities using regression analysis in the planning phase. The developed model is focused on the required quantities of reinforced concrete and bricks. In order to achieve the objective, the data of 44 educational facility projects collected from Gyeonggi-do was used in the regression model. This study can be utilized by major stakeholders to accurately predict construction costs by estimating the appropriate quantities of reinforced concrete and bricks in the planning design phase.

비율제한 및 과제제시방법에 따른 3, 4, 5세 유아의 비상징 수 비교능력 (An Investigation Into 3-, 4-, and 5-Year-Old Children's Nonsymbolic Magnitude Comparison Ability According to Ratio Limit and Task Condition)

  • 조우미;이순형
    • 아동학회지
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    • 제38권1호
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    • pp.117-126
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    • 2017
  • Objective: The purpose of this study was to investigate young children's nonsymbolic magnitude comparison ability according to ratio limit and task condition. Methods: The participants included 40 3-year-old children, 42 4-year-old children, and 41 5-year-old children recruited from 4 childcare centers located in Seoul, Korea. All magnitude comparison tasks were composed of image material tasks and concrete material tasks. In addition, each magnitude comparison task varied with the ratio of the two quantities; 0.5 ratio, 0.67 ratio, 0.75 ratio. Results and Conclusion: The results revealed that 3-, 4-, and 5-year-old children could perform nonsymbolic magnitude comparison tasks without learning experiences. Also, 3-, 4-, and 5-year-old children could perform concrete material tasks better than image material tasks in nonsymbolic magnitude comparison tasks. Furthermore, children's performance on nonsymbolic magnitude comparison tasks indicated the ratio signature of the approximate number system. Children have a degree of numerical capacity prior to formal mathematics instruction. Also, children were influenced by task conditions or sense stimulus when they processed numerical information. Furthermore, the approximate number system can be used in understanding the ordinality of number.

기상청 기후자료의 균질성 문제 (II): 통계지침의 변경 (Inhomogeneities in Korean Climate Data (II): Due to the Change of the Computing Procedure of Daily Mean)

  • 류상범;김연희
    • 대기
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    • 제17권1호
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    • pp.17-26
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    • 2007
  • The station relocations, the replacement of instruments, and the change of a procedure for calculating derived climatic quantities from observations are well-known nonclimatic factors that seriously contaminate the worthwhile results in climate study. Prior to embarking on the climatological analysis, therefore, the quality and homogeneity of the utilized data sets should be properly evaluated with metadata. According to the metadata of the Korea Meteorological Administration (KMA), there have been plenty of changes in the procedure computing the daily mean values of temperature, humidity, etc, since 1904. For routine climatological work, it is customary to compute approximate daily mean values for individual days from values observed at fixed hours. In the KMA, fixed hours were totally 5 times changed: at four-hourly, four-hourly interval with additional 12 hour, eight-hourly, six-hourly, three-hourly intervals. In this paper, the homogeneity in the daily mean temperature dataset of the KMA was assessed with the consistency and efficiency of point estimators. We used the daily mean calculated from the 24 hourly readings as a potential true value. Approximate daily means computed from temperatures observed at different fixed hours have statistically different properties. So this inhomogeneity in KMA climate data should be kept in mind if you want to analysis secular aspects of Korea climate using this data set.

과제 난이도에 따른 2, 4세 유아의 비상징적 연산능력 (An Investigation into 2, 4 Year Old Children's Nonsymbolic Arithmetic Ability According to Task Difficulty)

  • 조우미;이순형
    • 아동학회지
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    • 제36권4호
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    • pp.229-242
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    • 2015
  • The purpose of this study was to investigate young children's nonsymbolic arithmetic ability according to task difficulty. The participants in this study comprised 43 2-year-old children and 48 4-year-old children recruited from 5 childcare centers located in Seoul, Korea. All tasks were composed of comparison, addition, subtraction, multiplication and division tasks. In addition, each arithmetic task varied with the ratio of the two quantities; low level(1:2), middle level(2:3), high level(4:5). The results revealed that 2 & 4-year-old children could perform a large numerical range of nonsymbolic arithmetic tasks without influences from previously learned mathematics. This finding suggests that children have a degree of numerical capacity prior to symbolic mathematics instruction. Furthermore, children's performance on nonsymbolic arithmetic tasks indicated the ratio signature of large approximate numerical representation. This result implies that large approximate numerical representation can be used in arithmetical manipulations.

General evolutionary path for fundamental natural frequencies of structural vibration problems: towards optimum from below

  • Zhao, Chongbin;Steven, G.P.;Xie, Y.M.
    • Structural Engineering and Mechanics
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    • 제4권5호
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    • pp.513-527
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    • 1996
  • In this paper, both an approximate expression and an exact expression for the contribution factor of an element to the natural frequency of the finite element discretized system of a structure in general and a membrane in particular have been derived from the energy conservation principle and the finite element formulation of structural eigenvalue problems. The approximate expression for the contribution factor of an element is used to predict and determine the elements to be removed in an iteration since it depends only on the quantities associated with the old system in the iteration. The exact expression for the contribution factor of an element makes it possible to check whether the element is correctly removed at the end of an iteration because it depends on both the old system and the new system in the iteration. Thus, the combined use of the approximate expression and the exact expression allows a considerable number of elements to be removed in a single iteration so that the efficiency of the evolutionary structural optimization method can be greatly improved for solving the natural frequency optimization problem of a structure. A square membrane with different boundary supports has been chosen to investigate the general evolutionary path for the fundamental natural frequency of the structure. The related results indicated that if the objective of a structural optimization is to raise the fundamental natural frequency of the structure to an optimal value, the general evolutionary path during its optimization is that the elements are gradually removed along the direction from the area surrounded by the contour of the highest value to that surrounded by the contour of the lowest value.

Fourier Series Approximation for the Generalized Baumgartner Statistic

  • Ha, Hyung-Tae
    • Communications for Statistical Applications and Methods
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    • 제19권3호
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    • pp.451-457
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    • 2012
  • Baumgartner et al. (1998) proposed a novel statistical test for the null hypothesis that two independently drawn samples of data originate from the same population, and Murakami (2006) generalized the test statistic for more than two samples. Whereas the expressions of the exact density and distribution functions of the generalized Baumgartner statistic are not yet found, the characteristic function of its limiting distribution has been obtained. Due to the development of computational power, the Fourier series approximation can be readily utilized to accurately and efficiently approximate its density function based on its Laplace transform. Numerical examples show that the Fourier series method provides an accurate approximation for statistical quantities of the generalized Baumgartner statistic.