• Title/Summary/Keyword: prime factor

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Balancing air flow at terminal in CAV duct system with DPM method (정풍량방식 덕트에서 이중압력측정방법을 이용한 취출구 풍량조정)

  • 이대우;박명식;박영우
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.1
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    • pp.66-78
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    • 1998
  • Adequate ventilation with the proper amount of air to the right place is important factor to achieve a good Indoor air climate. Thus it is of prime importance that the ventilation system is working properly. This requires reliable pressure loss calculation to balance the air flow through duct systems. So a computer program for balancing CAV duct system is developed In this study. The results of CAV duct system is compared with the "Balans" code developed by Larsen from Norway. To obtain the pressure drop characteristics of damper at duct terminal, some experiments are performed using DPM(Dual Pressure Measurement) system. To adjust the resistance of damper, present study suggests that some special diffusers should be designed and damper producers should give the data of air flow vs. pressure drop to the customs when they manufacture the damper. One of the results concludes that the working time can be reduced from several minutes to several seconds per damper in the present experimental site, if the DPM system and the air volume adjusting process are used.

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A Sensitivity Analysis for Risk Management of Commercial Buildings (상업건축물의 사업위험관리를 위한 민감도 분석 기법)

  • Kim, Sun-Kuk;Ryu, Sang-Yeon
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.1
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    • pp.123-129
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    • 2009
  • The global financial crisis resulting from sub-prime mortgage crisis in the United States, beginning in 2007, has had dealt a blow to domestic economy. The economic downturn, coupled with a large number of apartments remaining unsold has resulted in contracted investment sentiment of the builders. Thus it's difficult to even implement the business, unless the investment project is thoroughly verified as well as the accurate profitability is granted. Viewing the current situation, forecasting and evaluating the business profitability is more than important today. The study was planned to identify the factors influencing the business success and to evaluate the sensitivity, relative risk of each factor was measured, and the scope of the study was limited to the commercial buildings among other buildings except apartment buildings. Hence, the study was aimed to analyze the factors affecting the business and the sensitivity so as to be able to systematically materialize the risk management of the commercial buildings. The outcome of the study is expected to serve the useful data in analyzing the business profitability and implementing the investment projects as well.

On the mixed-mode crack propagation in FGMs plates: comparison of different criteria

  • Nabil, Benamara;Abdelkader, Boulenouar;Miloud, Aminallah;Noureddine, Benseddiq
    • Structural Engineering and Mechanics
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    • v.61 no.3
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    • pp.371-379
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    • 2017
  • Modelling of a crack propagating through a finite element mesh under mixed mode conditions is of prime importance in fracture mechanics. In this paper, two crack growth criteria and the respective crack paths prediction in functionally graded materials (FGM) are compared. The maximum tangential stress criterion (${\sigma}_{\theta}-criterion$) and the minimum strain energy density criterion (S-criterion) are investigated using advanced finite element technique. Using Ansys Parametric Design Language (APDL), the variation continues in the material properties are incorporated into the model by specifying the material parameters at the centroid of each finite element. In this paper, the displacement extrapolation technique (DET) proposed for homogeneous materials is modified and investigated, to obtain the stress intensity factors (SIFs) at crack-tip in FGMs. Several examples are modeled to evaluate the accuracy and effectiveness of the combined procedure. The effect of the defects on the crack propagation in FGMs was highlighted.

Origins of Brand Image, Customer Satisfaction, and Loyalty toward Telecommunication Service: An Emerging Market Perspective

  • Hossain, Md. Alamgir;Kim, Min-Ho;Jahan, Nusrat;Min, Bo-Yeon
    • Asia-Pacific Journal of Business
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    • v.9 no.2
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    • pp.39-57
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    • 2018
  • As competition grows in the telecommunication service industry, understanding the origins of brand image and consumer behavioral intentions challenges practitioners to design an effective marketing strategy and branding plan. In this paper, brand image and behavioral relationships are investigated in Bangladesh, an emerging market that has a particular socio-cultural and economic context of one of the most densely populated countries of South Asia. This study employs confirmatory factor analysis and structural equation modeling to analyze the database. Empirical testing and the proposed model suggest that brand image is the prime determinant of consumer satisfaction and loyalty. The results highlight the importance of perceived value, perceived trust and price structure to project brand image and satisfaction. Additionally, confirmation exhibits a stronger total effect of brand image on customer loyalty. Empirical findings extensively contribute to the theoretical and managerial understanding of subscribers' attitudes toward telecommunication service in an emerging market context.

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Flow-induced Vibration Analysis of Bridge Girder Section (교량 구조물의 유체유발 진동해석)

  • Park, Seong-Jong;Kwon, Hyuk-Jun;Lee, In;Han, Jae-Heung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.5
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    • pp.402-409
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    • 2004
  • Numerical analysis of static and dynamic wind effects on civil engineering structures was performed. Long-span suspension bridges are flexible structures that are highly sensitive to the action of the wind. Aerodynamic effect often becomes a governing factor in the design process of bridges and aeroelastic stability boundary becomes a prime criterion which should be confirmed during the structural design stage of bridges because the long-span suspension bridges are prone to the aerodynamic instabilities caused by wind. If the wind velocity exceeds the critical velocity that the bridge can withstand, then the bridge fails due to the phenomenon of flutter. Buffeting caused by turbulence results in structural fatigue, which could lead to the failure of a bridge. Navier-Stokes equations are used for the aeroelastic analysis of bridge girder section. The aeroelastic simulation is carried out to study the aeroelastic stability of bridges using both Computational Fluid Dynamic (CFD) and Computational Structural Dynamic (CSD) schemes.

Temperature and Leakage Current Characteristics of Polymeric Surge Arrester with Housing (폴리머 피뢰기의 구조에 따른 온도와 누설전류 특성)

  • Cho, Han-Goo;You, Dae-Hoon;Lee, Un-Yong;Kim, Ha-Na
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.3
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    • pp.273-280
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    • 2007
  • In this paper, the ZnO surge arrester performance of power distribution class has been studied under different manufacturing conditions such as housing materials(polymeric, porcelain), interface sealants and one-body molding type. In the recent years, the polymeric ZnO surge arresters have been developed and put into operations based on their excellent characteristics. For polymeric surge arresters, the inner gas volume is extremely small, especially in solid insulation polymeric arresters there are not any gas volume inside arresters in the structure due to polymeric materials are filled into the internal gas volume. The sealing integrity is related to safe operation of surge arrester, the prime failure reason of porcelain housed arresters is moisture ingress. In this paper, the sealing integrity of polymeric surge arresters is investigated with moisture multi-aging test and ingress test. The evaluation techniques are used to inspect the sealing integrity of polymeric arresters, including leakage current, surface temperature, reference voltage and dissipation factor.

A Study on Prediction Method of Sky Luminance Distributions for CIE Overcast Sky and CIE Clear Sky (CIE 표준 담천공과 청천공 모델의 천공 휘도분포 예측 방법에 관한 연구)

  • Kim, Chul-Ho;Kim, Kang-Soo
    • Journal of the Korean Solar Energy Society
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    • v.36 no.3
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    • pp.33-43
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    • 2016
  • Daylight is an important factor which influences building energy efficiency and visual comfort for occupants. It is important to predict precise sky luminance at the early stages of design to reduce light energy in the building. This study predicted sky luminance distributions of standard sky model(CIE overcast sky, CIE clear sky) that was provided from the CIE(Commission internationale de $l^{\prime}{\acute{e}}clairage$). Afterward, result of sky luminance was compared and verified with simulation value of Radiance program. From the CIE overcast sky, zenith and horizon ratio is about 3:1. From the CIE clear sky, luminance value gets most high value around the sun. On the other hand, luminance value is the lowest in the opposite direction of the sun when angle is $90^{\circ}$ between the sun and sky element. As a result of comparing the calculation results with Radiance program, sky luminance prediction error rate is 0.4~1.3% when it is CIE overcast sky. Also, sky luminance prediction error rate is 0.3~1.5% when it is CIE clear sky. When compared with the results of radiance simulation, it was evaluated as fairly accurate.

High Correlation between Alu Elements and the Conversion of 3' UTR of mRNAs Processed Pseudogenes

  • An, Hyeong Jun;Na, Dokyun;Lee, Doheon;Lee, Kwang Hyung;Bhak, Jonghwa
    • Genomics & Informatics
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    • v.2 no.2
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    • pp.86-91
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    • 2004
  • Even though it represents $6-13\%$ of human genomic DNA, Alu sequences are rarely found in coding regions. When in exon region, over $80\%$ of them are found in 3' untranslated region (UTR). Pseudogenes are an important component of human genome. Their functions are not clearly known and the mechanism of how they are generated is still debatable. Both the Alu and Pseudogenes are important research problems in molecular biology. mRNA is thought to be a prime source of pseudogene and active research is going on its molecular mechanism. We report, for the first time, that mRNAs containing Alu repeats at 3' UTR has a significantly high correlation with processed pseudogenes, suggesting a possibility that Alu containing mRNAs have a high tendency to become processed pseudogenes. It is known that about $10\%$ of all human genes have been transposed. Transposed genes at 3' UTR without Alu repeat have about two processed pseudogenes per gene on average while we found with statistical significance that a transposed gene with Alu had over three processed Pseudogenes on average. Therefore, we propose Alu repeats as a new and important factor in the generation of pseudogenes.

Task Assignment Model for Crowdsourcing Software Development: TAM

  • Tunio, Muhammad Zahid;Luo, Haiyong;Wang, Cong;Zhao, Fang;Gilal, Abdul Rehman;Shao, Wenhua
    • Journal of Information Processing Systems
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    • v.14 no.3
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    • pp.621-630
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    • 2018
  • Selection of a suitable task from the extensively available large set of tasks is an intricate job for the developers in crowdsourcing software development (CSD). Besides, it is also a tiring and a time-consuming job for the platform to evaluate thousands of tasks submitted by developers. Previous studies stated that managerial and technical aspects have prime importance in bringing success for software development projects, however, these two aspects can be more effective and conducive if combined with human aspects. The main purpose of this paper is to present a conceptual framework for task assignment model for future research on the basis of personality types, that will provide a basic structure for CSD workers to find suitable tasks and also a platform to assign the task directly. This will also match their personality and task. Because personality is an internal force which whittles the behavior of developers. Consequently, this research presented a Task Assignment Model (TAM) from a developers point of view, moreover, it will also provide an opportunity to the platform to assign a task to CSD workers according to their personality types directly.

Complex Interplay between the RUNX Transcription Factors and Wnt/β-Catenin Pathway in Cancer: A Tango in the Night

  • Sweeney, Kerri;Cameron, Ewan R.;Blyth, Karen
    • Molecules and Cells
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    • v.43 no.2
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    • pp.188-197
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    • 2020
  • Cells are designed to be sensitive to a myriad of external cues so they can fulfil their individual destiny as part of the greater whole. A number of well-characterised signalling pathways dictate the cell's response to the external environment and incoming messages. In healthy, well-ordered homeostatic systems these signals are tightly controlled and kept in balance. However, given their powerful control over cell fate, these pathways, and the transcriptional machinery they orchestrate, are frequently hijacked during the development of neoplastic disease. A prime example is the Wnt signalling pathway that can be modulated by a variety of ligands and inhibitors, ultimately exerting its effects through the β-catenin transcription factor and its downstream target genes. Here we focus on the interplay between the three-member family of RUNX transcription factors with the Wnt pathway and how together they can influence cell behaviour and contribute to cancer development. In a recurring theme with other signalling systems, the RUNX genes and the Wnt pathway appear to operate within a series of feedback loops. RUNX genes are capable of directly and indirectly regulating different elements of the Wnt pathway to either strengthen or inhibit the signal. Equally, β-catenin and its transcriptional co-factors can control RUNX gene expression and together they can collaborate to regulate a large number of third party co-target genes.