• Title/Summary/Keyword: External Supply Factors

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Thermal Analysis Associated with the Application of Pipte Cooling System to a massive Concrete Structure (매스콘크리트 구조물에서 파이프쿨링을 고려한 수화열 해석)

  • 김상철;이두재;김재권;강석화;김진근
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10b
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    • pp.922-927
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    • 1998
  • Pipe cooling has been popularly used in the mass concreting work to reduce temperature of the structure since it is known to be the easiest way to apply and has been the customary usage. But wrong application of the system results in the harmful effect on the structure by crack formation due to thermal shocks and improper cooling schemes. Thus, this study aims at the suppling of effective cooling methods through parametric study. For this, circulating method, velocity of water supply and circulating duration were selected as critical factors affecting the effectiveness of cooling system. As a results of thermal analysis, it was found that too much thermal gradient in the vicinity of the pipe creates localized radial or circumferential cracks. The duration of circulating cooling may be recommended to be as short as several days which may safely reduce the concrete temperature to below a final stable value. It was also found that pipe cooling is more effective to decrease the degree external restraints than internal one.

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Oil Price Forecasting Based on Machine Learning Techniques (기계학습기법에 기반한 국제 유가 예측 모델)

  • Park, Kang-Hee;Hou, Tianya;Shin, Hyun-Jung
    • Journal of Korean Institute of Industrial Engineers
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    • v.37 no.1
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    • pp.64-73
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    • 2011
  • Oil price prediction is an important issue for the regulators of the government and the related industries. When employing the time series techniques for prediction, however, it becomes difficult and challenging since the behavior of the series of oil prices is dominated by quantitatively unexplained irregular external factors, e.g., supply- or demand-side shocks, political conflicts specific to events in the Middle East, and direct or indirect influences from other global economical indices, etc. Identifying and quantifying the relationship between oil price and those external factors may provide more relevant prediction than attempting to unclose the underlying structure of the series itself. Technically, this implies the prediction is to be based on the vectoral data on the degrees of the relationship rather than the series data. This paper proposes a novel method for time series prediction of using Semi-Supervised Learning that was originally designed only for the vector types of data. First, several time series of oil prices and other economical indices are transformed into the multiple dimensional vectors by the various types of technical indicators and the diverse combination of the indicator-specific hyper-parameters. Then, to avoid the curse of dimensionality and redundancy among the dimensions, the wellknown feature extraction techniques, PCA and NLPCA, are employed. With the extracted features, a timepointspecific similarity matrix of oil prices and other economical indices is built and finally, Semi-Supervised Learning generates one-timepoint-ahead prediction. The series of crude oil prices of West Texas Intermediate (WTI) was used to verify the proposed method, and the experiments showed promising results : 0.86 of the average AUC.

A Multi-agent System based on Genetic Algorithm for Integration Planning in a Supply Chain Management (유전 알고리즘에 기반한 동적 공급사슬 통합계획을 위한 멀티 에이전트 시스템)

  • Park, Byung-Joo;Choi, Hyung-Rim;Kang, Moo-Hong
    • Journal of Intelligence and Information Systems
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    • v.13 no.3
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    • pp.47-61
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    • 2007
  • In SCM (supply chain management), companies are pursuing a new approach through which overall functions within the supply chain, ranging from material purchase to production, distribution, and sales are designed, planned, and managed in an integrated way. The core functions among them are production planning and distribution planning. As these problems are mutually related, they should be dealt with simultaneously in an integrated manner. SCM is large-scale and multi-stage problems. Also, its various kinds of internal or external factors can, at any time, dynamically bring a change to the existing plan or situation. Recently, many enterprises are moving toward an open architecture for integrating their activities with their suppliers, customers and other partners within the supply chain. Agent-based technology provides an effective approach in such environments. Multi-agent systems have been proven suitable to represent domains such as supply chain networks which involve interactions among manufacturing organization, their customers, suppliers, etc. with different individual goals and propriety information. In this paper, we propose a multi-agent system based on the genetic algorithm that make it possible to integrate the production and distribution planning on a real-time basis in SCM. The proposed genetic algorithm produced near optimal solution and we checked that there is a great difference in the results between integrated planning and non-integrated planning.

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The Express-Assessment of Main Monetary Indicators of Russia and the Countries of CIS

  • Vyborova, Elena Nikolaevna
    • East Asian Journal of Business Economics (EAJBE)
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    • v.6 no.1
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    • pp.1-31
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    • 2018
  • Purpose - This study is to analyze indicators characterizing the monetary turnover and its determining factors. Also this paper looked at the evolution of monetary aggregates of the Russian Federation, Australian, Sweden, Denmark, countries of CIS at the present stage of development and in the historical context. Research design, data, and methodology - The scale of research on Russia: to be analyzed the amount of data from the 2011 by 2016. In the historical context of the estimated data in the 1900-2011. On Belarus - the 2007-2017, on Tajikistan - the 2000 - 2017, on Kazakhstan - the 2000-2017, on Kyrgyzstan - the 2000-2017, on Australian - the 1959-2017, on Sweden - the 2009-2017, on Denmark - the 1999-2017. Results - Hypothesis 1. In Russian Federation the monetary stock has the steady tendency to growth. The dynamics of money supply in Russia is largely determined by historical events. Hypothesis 2. The dynamics of money supply the leading countries-partners has the tendency to grow. The monetary amount of countries-partners are analyzed is largely determined by external debt, GDP, the exports, the imports, the international reserves. Conclusions - The dynamics of monetary stock of Russia is determined by the historical events in many respects. The Russian Federation maintains a steady and the liquid economic position in the case of considerable amount of monetary stock and the high degree of its surplus. In most of the countries studied, the monetary supply has a significant volume exceeding the needs of the economy. If the distribution of monetary mass is adequate and there is a vertical of financial control, this will not have a negative impact on the country's economic stability and the development.

A Study on Procurement of Construction Materials in the HwaSeong Construction Project (화성건설공사에서 자재의 조달방법 연구)

  • Kim, Kyoon-Tai
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.6
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    • pp.183-188
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    • 2009
  • HwaSeong (Suwon Fortress) was built during the reign of King Jeong-jo in the Choseon Dynasty. Detailed information on the construction of HwaSeong can be found in Hwaseong Seongyeok Euigui. In this sense, it is necessary to perform a comparative analysis on the Hwaseong Seongyeok Euigui based on construction management factors. This paper aims to analyze the HwaSeong construction project from a modern construction perspective by comparing and reviewing information related to the procurement of construction materials of the time. For this, wooden and steel materials and tiles were analyzed by supply area, supply channel, type and price. From the results of the analysis, it is found that the government used both private and official channels to supply materials. In particular, except for wooden materials that could be supplied from Bongsan, the supply of materials showed a high dependency on private channels. In terms of steel, it was almost 30 percent cheaper through private channels than when purchased through the official channel. Finally, materials vulnerable to damage like tiles were manufactured from the areas near the construction site. From this fact it can be interpreted that the government had a flexible procurement system, including manufacturing on the spot and external suppliers,depending on the property of the material. It is expected these analytical results will serve as key data to understand the management factors in constructing HwaSeong.

Stable C and N Isotopes: A Tool to Interpret Interacting Environmental Stresses on Soil and Plant

  • Yun, Seok-In;Ro, Hee-Myong
    • Journal of Applied Biological Chemistry
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    • v.51 no.6
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    • pp.262-271
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    • 2008
  • Natural abundances of stable isotopes of nitrogen and carbon (${\delta}^{15}N$ and ${\delta}^{13}C$) are being widely used to study N and C cycle processes in plant and soil systems. Variations in ${\delta}^{15}N$ of the soil and the plant reflect the potentially variable isotope signature of the external N sources and the isotope fractionation during the N cycle process. $N_2$ fixation and N fertilizer supply the nitrogen, whose ${\delta}^{15}N$ is close to 0%o, whereas the compost as. an organic input generally provides the nitrogen enriched in $^{15}N$ compared to the atmospheric $N_2$. The isotope fractionation during the N cycle process decreases the ${\delta}^{15}N$ of the substrate and increases the ${\delta}^{15}N$ of the product. N transformations such as N mineralization, nitrification, denitrification, assimilation, and the $NH_3$ volatilization have a specific isotope fractionation factor (${\alpha}$) for each N process. Variation in the ${\delta}^{13}C$ of plants reflects the photosynthetic type of plant, which affects the isotope fractionation during photosynthesis. The ${\delta}^{13}C$ of C3 plant is significantly lower than, whereas the ${\delta}^{13}C$ of C4 plant is similar to that of the atmospheric $CO_2$. Variation in the isotope fractionation of carbon and nitrogen can be observed under different environmental conditions. The effect of environmental factors on the stomatal conductance and the carboxylation rate affects the carbon isotope fractionation during photosynthesis. Changes in the environmental factors such as temperature and salt concentration affect the nitrogen isotope fractionation during the N cycle processes; however, the mechanism of variation in the nitrogen isotope fractionation has not been studied as much as that in the carbon isotope fractionation. Isotope fractionation factors of carbon and nitrogen could be the integrated factors for interpreting the effects of the environmental factors on plants and soils.

Determinant Factors and Recognition about Silver Town according to Baby Boomer's Life Style (베이비부머의 라이프스타일에 따른 실버타운에 대한 인식과 선호 결정요인)

  • Su, In-Ae;Hong, Hyung-Ock;Lee, Hyun-Jung
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2011.04a
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    • pp.220-225
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    • 2011
  • The purpose of this study was to identify the lifestyle of babyboomer, the difference of recognition about silver town and preferable determinants according to lifestyle. By the Social Survey Research with questionnaire, data from 108 people of 46 years old ~ 65 years old who inhabited in Seoul City area were collected during October, 2010. Data were analyzed by the SPSS program Win 18.0, and frequency, percentage, t-test, ANOVA, factor analysis, regression were employed. The major findings were as follows. First, by the factors analysis on lifestyle, factors were named "interest about external", "inner-oriented", "pursuit of health", "prepare for later life", "social aspects". Second, by the frequency analysis on recognition about silver town, 97.2% of total respondents replied "at least heard about silver town", and 64.8% of total respondents recognized the necessity of silver town. While, intention to live in silver town was low (by 38.0% of total respondents). Third, by the regression analysis on preference tendency about silver town according to life style, factor of 'inner-oriented' in the decision about residential area and total household number, factor of 'pursuit of health' in the decision about monthly rent, factor of 'social aspects' in the decision about cost solution method were influential factors. In conclusion, to supply the house which had the diversity of baby bommer's life style, government and corporation's efforts to increase intention to live in silver town and to change the recognition about silver town are needed.

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A Study on the Establishment of Smart Factory through the Environmental Factors and Absorption Capacity of Small and Medium Businesses (중소기업의 환경요인과 흡수역량을 통한 Smart Factory 구축 연구)

  • Jin, Sung-Ok;Seo, Young Wook
    • Journal of Convergence for Information Technology
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    • v.9 no.7
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    • pp.67-77
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    • 2019
  • Many small and medium-sized enterprises are deploying Smart Factory without due consideration of the circumstances in which the entity is in or outside of the entity, such as environmental changes and the capabilities of its members. Therefore, utilization and effectiveness are also low after deployment. This study verifies 'the establishment of a Smart Factory through the environmental factors and absorption capabilities of small businesses' through empirical research. The survey was received by people working for small and medium-sized companies that have established Smart Factory. The results of the study showed that first, environmental factors within and outside the company had a positive effect on the absorption capacity within the company. Second, the absorption capacity within a company has had a positive effect on the deployment of a Smart Factory. Based on the above proof, it has been proved to be effective if the core areas of the Smart Factory are built on the basis of the company's internal and external environmental factors and absorption capabilities when constructing Smart Factory in small businesses. In the future, we will study the achievements of smart factory construction.

An Analysis Acceptance Factors for the Early Diffusion of Mulberry Protected Cultivation (오디 시설재배 조기 확산을 위한 수용요인분석)

  • Kim, Woong;Lee, Ki Kwon;Yu, Young Seok;Choi, Don Woo
    • Journal of Agricultural Extension & Community Development
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    • v.21 no.2
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    • pp.29-56
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    • 2014
  • This study conduct for 200 farmhouses who didn't accept new technology like mulberry Protected Cultivation. Through research model combined Innovation diffusion theory(IDT) and Technology Acceptance Model(TAM), it analysed which factors affect for new technology acceptance and diffusion. To verify relations between external factors which affect new technology acceptance and diffusion by endogenous variables such as perceived usefulness, perceived ease of use and perceived riskiness, with external factors, mothed used to analyse it. Most of adopted variables were showed positive results except for individual innovativeness and reliability. Based on the results of these analyses, we can suggest rapid. First, technique diffusion agents should have heighten the level of expertise and technology, and build up the network to solve difficulties with technique supply with mulberry farmhouses. Secondly farmhouses of mulberry outdoor cultivation showed positive attitude protected cultivation, but negative attitude it bacause of the burden of facilities investment. Thus, it is needed to capital investment for individual farmhouse hold. Finally, through cultivation technology education, field trip about mulberry protected cultivation, we can diffuse technology receive for negative farmers.

An analysis of time series models for toilet and laundry water-uses (변기 및 세탁기 가정용수 사용량의 시계열모형 연구)

  • Myoung, Sungmin;Kim, Donggeon;Lee, Doo-Jin;Kim, Hwa Soo;Jo, Jinnam
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.6
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    • pp.1141-1148
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    • 2013
  • End-uses of household water have been influenced by a housing type, life style and housing area which are considered as internal factors. Also, there are external factors such as water rate, weather and water supply facilities. Analysis of influential factors on water consumption in households would give an explanation on the cause of changing trends and would help predicting the water demand of end-use in household. In this paper, we used real data to predict toilet and laundry water-uses and utilized the linear regression model with autoregressive errors. The results showed that the monthly autoregressive error models explained about 71% for describing the water demand of end-use in toilet and laundry water-uses.