• Title/Summary/Keyword: variable power factor

Search Result 280, Processing Time 0.032 seconds

A review on dynamic characteristics of nonlocal porous FG nanobeams under moving loads

  • Abdulaziz Saud Khider;Ali Aalsaud;Nadhim M. Faleh;Abeer K. Abd;Mamoon A.A. Al-Jaafari;Raad M. Fenjan
    • Steel and Composite Structures
    • /
    • v.50 no.1
    • /
    • pp.15-24
    • /
    • 2024
  • This research presents dynamical reaction investigation of pore-dependent and nano-thickness beams having functional gradation (FG) constituents exposed to a movable particle. The nano-thickness beam formulation has been appointed with the benefits of refined high orders beam paradigm and nonlocal strain gradient theory (NSGT) comprising two scale moduli entitled nonlocality and strains gradient modulus. The graded pore-dependent constituents have been designed through pore factor based power-law relations comprising pore volumes pursuant to even or uneven pore scattering. Therewith, variable scale modulus has been thought-out until process a more accurate designing of scale effects on graded nano-thickness beams. The motion equations have been appointed to be solved via Ritz method with the benefits of Chebyshev polynomials in cosine form. Also, Laplace transform techniques help Ritz-Chebyshev method to obtain the dynamical response in time domain. All factors such as particle speed, pores and variable scale modulus affect the dynamical response.

A Study on Balanced -type Oseillating Mole-Drainer(III)-Model Test for Draft Force, Torque, Power and Moment (평행식 진동탄환 암거 천공기의 연구(III)-견인력, 토크, 동력 및 모멘크에 관한 모형시험-)

  • 김용환
    • Journal of Biosystems Engineering
    • /
    • v.1 no.1
    • /
    • pp.1-6
    • /
    • 1976
  • This paper is the third one of the study on balanced type oscillating mole-drainer, the first one was presented in No 9. Gyeongsang College Report and the second one in Vol. 17, No.4 of the KSAE. In the first part of this study, the characteristics of traction forces between the nonoscillating earth working equipments and oscillating ones was compared. A model of the balanced type oscillating mole-drainer, which composed of a mechanism that may reduce the machine vibration, was designed following the dimensional analysis and similitude technique. The model test was carried out to clarify the balancing mechanism of the oscillating parts and other parts of the machine. In the light of the results from the model tests, a prototype machine was made for experimental purpose. Results from the field test by a reported in the near future. In the second report, the model tests were carried out under the same soil conditions, i.e, . oscillating frequency, running velocity, and oscillating amplitude, etc. It was clear that use of balanced type oscillating model could substantially reduce the vibration of the whole system of the machine, when compared with the nonoscillating type model. In this paper(the third report), results of investigation on the traction force, power requirement, and moment. etc, is presented. Analysis of variance technique was used for analyzing the effect of the frequency, amplitude, and running velocity on the draft force, torque, power requirements, and moments. The results obtained from the model tests are as follows, 1) By practicing a balanced-type oscillating mole-drainer, it was possible to reduce the traction resistance by 55.1-61. 2 percent of traction resistance, however, was 1.75 - 1.95 times greater than the value of resistance which was induced by use of a mole-drainer with single bullet. The resistance of rear shank against soil was considered as a main causing factor of the above results. 2) As the oscillation frequency was increased, the traction resistance was decreased. Considering on the effect of oscillation the greater the amplitude, and the slower the running velocity was, the greater the reduction ratio of traction resistance was. 3) The ratio of the traction resistance of oscillating mole-drainer to that of non-oscillating one could be represented as a function of dimensionless variable (V/$Af$). The results from the tests were well agreed with the reported results from the experim ents on oscillation plow or hoe. 4) By taking a lower value of (V/$Af$), reducing the traction resistance was possible. This fact meant, however, that the efficiency of mole drain practice would be lower. 5) It was experimentally confirmed under the same condition of soil that the variable (R/$rD1^3$) could be represented as a function of a variable($V^2/gD$) when a non\ulcornerocillating mole-drainer was used. 6) When a oscillating mole-drainer was used, the variable(R/$rD_1^{3}$) could be represented as a function of two variables ($v^2/gD_1$) and (V^2/gD_1$). 7) The torque was not affected by a change of frequency. However, a relation of proportionality existed between torque and amplitude, running velocity, and ratio of bullet diameter. When a balanced type oscillating mole-drainer with two bullets was used, torque was increased by 52.8-78. 4 percent and total power requirement was also increased. 8) Total power requirement was increased linearly in accordance with the increasing frequency, 41.96 percent of total power was used for oscillating action. The magnitude of total power requirement was 1. 8-9. 4 times greater than that of a non-oscillating mechanism. In the view point of power requirement, it was not advisable to increase the frequency, amplitude, running velocity, and ratio of bullet diameter at the same time. 9) Only the positive moment occured in the rear shank. Change of the diameter of a rear bullet, could not affect the balancing against the soil resistance. It was necessary for rear bullet to have a large resistance against soil only when the rear bullet was in backward motion. 10) Within an extent of the experimental base, optimum limits for several design factors were A=0.5cm, $f$=22.5Hz, V=O. 05m/sec, and $\lambda$=1.0 By adapting these values traction resistance was reduced by 40 percent and vibration acceleration wa s reduced by 60 percent. Even though the total , power requirements for operating a balanced type oscillation mechanism was greater ~than that of non-oscillating one, using a oscillating mechanism would be more effective. Because a balanced type oscillating mechanism is used, tractive resistance will be reduced and then the lighter . tractive equipment could be used.

  • PDF

An Empirical Study on the Determinants and Effects of Korean FDI in Manufacturing Industries (한국기업(韓國企業)의 해외직접투자(海外直接投資) 결정요인형태(決定要因形態)에 관한 실증(實證) 연구(硏究))

  • Lee, Eung-Kweon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.27
    • /
    • pp.183-213
    • /
    • 2005
  • This study is achieving overseas investment to be kept and manages important position in business scope because Korean Company achieves business in major market in world and goes forward. under proposition that development(foreign direct investment) previous engagement can not but differ with advanced nation enterprise's model in over sea direct investment achievement. Grasp ramification(pattern change substance) of overseas direct investment since the 1990 to korean manufacture Firm(enterprise). Seek political consultation by analyzing change of factor and investment decision factor by year in dimension by industry investment winter season by year affecting in oversea direct investment and was attained in purpose to verify existent theory's explanation power connected with investment previous engagement. This is that can develop and procure competitive advantage of enterprise peculiarity by making overseas direct investment adversely with existent theory that can make foreign country direct investment though there is high position of enterprise characteristic's competitive advantage and move of knowledge and information is important in korean firm's overseas direct investment in globalization roadbed in at least own field through change and renovation establish experiment model under proposition that should grope more active previous engagement than advanced nation enterprise and arranged subject of study if it is korean's firm that wish to become universal guidance enterprise. and examine trend of direct investment and actual conditions invested first in the foreign countries as examples by investment department, by investment industry inside of investment scale etc..., establish korean firm's invest area selection and decision and investment very important person and effect analysis Circumstance-model that is based in strategic adaptedness by year. Circumstance-variable have influenced how in overseas direct investment and decision and what variable will be considered first in over sea direct investment did Empirical analysis in here after

  • PDF

Causes and Overcoming of the Algae Excess in a Dam Water - Based on the Data of Water Quality Analysis of Mulgum Area - (댐호화된 하천의 조류 과다 발생원인과 해소 방안 - 낙동강 물금 지역의 수질 분석 데이터를 중심으로 -)

  • Yang, Shi-Chun;Xia, Tian-Tian;Kang, Tai-Ho
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.20 no.4
    • /
    • pp.1-13
    • /
    • 2017
  • The purpose of this study is to analyze a term of decade of water quality data of the Mulgum intake station on the Nakdong river(dam) to find the cause of algal blooms and to set an alternative to prevent artificial lake water pollution. Our study shows that water quality changes have regular periodic regularity and there was a certain correlation between specific analytical items. According to the analysis results of each factor, the decline in precipitation was not the main reason for algal blooms. TP concentration had a slight effect on Chl-a concentration but was not a limiting nutrient of a bloom. TN concentration had a strong correlation with Chl-a and strongly negative correlation with temperature, but was not a bloom's limiting nutrient, and was only a dependent variable. As the temperature was negatively correlated with the Chl-a concentration, it is found that the aspect of the ecological influence of the temperature was the most important factor of the phytoplankton concentration change. The N/P ratio lies under a power function with a high degree of reliability by the TP concentration, and the phenomenon appeared to be the same as the results of two other comparative areas. This result confirms that TN is dependent on TP and the biota in the lake that TN is a dependent variable whose concentration is determined by TP it. In conclusion, the increase in lake bloom is the result of a food chain change, and it is necessary to control the ecosystem by the food chain in the lake in order to reduce the lake's bloom. In particular, it is important to keep the benthic ecosystem as wide as possible in the aerobic state.

Modelling and Factor Analysis of Pricing Determinants in the State-Regulated Competitive Market: The Case of Ukrainian Flour Market

  • Dragan, Olena;Berher, Alina;Plets, Ivan;Biloshkurska, Nataliia;Lysenko, Nataliia;Bovkun, Olha
    • International Journal of Computer Science & Network Security
    • /
    • v.21 no.7
    • /
    • pp.211-220
    • /
    • 2021
  • The aim of the study is to implement a factor analysis of the determinants of pricing in a state-regulated competitive market using economic and mathematical modelling methods and to develop ways to improve the pricing environment of the market under study. The purpose of the work defines the main objectives: (i) to investigate the features of the competitive model of the Ukrainian flour market; (ii) to analyse the current price conjuncture of the flour market and the dynamics of the main determinants of pricing; (iii)to develop ways of improving the price situation on the flour market on the basis of the factor analysis on the results of economic and mathematical modelling. In order to ensure the reliability and validity of the research results, the following methods were applied: the logical-dialectical method of scientific knowledge in the study of the main theoretical aspects of flour market functioning, the method of logical generalisation and synthesis, comparison, factor analysis, correlation and regression analysis, the graphical method, etc. It has been shown that pricing in a state-regulated competitive market has its own characteristics. For example, in the flour market the price of goods cannot be influenced by producers (sellers) by any methods, therefore determinants of pricing by indirect influence have been taken into account. The five-factor power model of wheat flour price has been constructed. It was substantiated that the price of wheat flour in Ukraine is mostly influenced by consumer price index (0.92 %). The received complex model of wheat flour price may be used also for medium-term forecasting and working out the ways of price formation optimization in the flour market.

Determinants of Business-to-Business Adoption in Fishery Wholesale Firms (수산물 B2B 도입 영향요인 분석)

  • Kim, Jin-Baek
    • The Journal of Fisheries Business Administration
    • /
    • v.36 no.2 s.68
    • /
    • pp.53-69
    • /
    • 2005
  • The recent emergence of electronic commerce could provide different opportunities to small firms in overcoming part of their technological, environmental, organizational, and managerial inadequacies. However, recent research provided a gloomy picture about electronic commerce uptake and use in small firms. Until now few small flrms adopted electronic commerce. This phenomenon gives us several implications. One of the implications is a need to generate more research to small firms' uptake and use of electronic commerce. So, this research aims at what is determinants in small firms' adoption of electronic commerce, especially business - to - business(B2B). Several previous studies were identified various influential variables in adoption of small firms' electronic commerce. To some extent, by industries these variables may be different in influencing B2B adoption of small firms. This study selected fishery industry's wholesale firms as survey domain. Then, It selected some variables from previous studios and group them in several factors for consistently comparing variable's influential power. Through hierarchical influencing model of B2B adoption, managers who worked for fishery wholesale firms were surveyed. Among the first level's factors of the model, business factor was identified as the statistically most influential factor in B2B adoption. Technological factor and environmental factor at the frist level were identified as relatively less influential factors. Among the second level's factors of the model, it was statistically significant only that technological usefulness factor was more influential than technological burden factor in B2B adoption. And among the third level's factors of the model, it was identified that formal plan and task team for B2B, top management support, and mutual beliefs of inter - firms were statistically more influential than related variables in B2B adoption. These results give us some implications. First, fishery wholesale firms recognized B2B as a new business paradigm, and technological problems as not obstacles in adopting B2B. Thus it would be possible to activate the fishery B2B if they were guided to getting B2B benefits and B2B's relative advantages. Second, they considered the power of influential factors might be different by B2B stages. That is, top management support was more important in the B2B introduction stage, and formal plan and task team for B2B and mutual beliefs of inter - firms were more important in the B2B operation stage.

  • PDF

PRESSURE BASED ROUTING PROTOCOL FOR UNDERWATER WIRELESS SENSOR NETWORKS: A SURVEY

  • Khasawneh, Ahmad;Bin Abd Latiff, Muhammad Shafie;Chizari, Hassan;Tariq, MoeenUddin;Bamatraf, Abdullah
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.2
    • /
    • pp.504-527
    • /
    • 2015
  • Underwater wireless sensor networks (UWSNs) are similar to the terrestrial sensor networks. Nevertheless, there are different characteristics among them such as low battery power, limited bandwidth and high variable propagation delay. One of the common major problems in UWSNs is determining an efficient and reliable routing between the source node and the destination node. Therefore, researchers tend to design efficient protocols with consideration of the different characteristics of underwater communication. Furthermore, many routing protocols have been proposed and these protocols may be classified as location-based and location-free routing protocols. Pressure-based routing protocols are a subcategory of the location-free routing protocols. This paper focuses on reviewing the pressure-based routing protocols that may further be classified into non-void avoidance protocols and void avoidance protocols. Moreover, non-void avoidance protocols have been classified into single factor based and multi factor based routing protocols. Finally, this paper provides a comparison between these protocols based on their features, performance and simulation parameters and the paper concludes with some future works on which further study can be conducted.

Evaluating Explanatory Power of Solar Intensity as Determining Factor of Housing Density in Intermontane Basin (산간분지에서 주택밀도의 결정인자로서 태양광도의 영향력 평가)

  • Um, Jung-Sup
    • Journal of the Korean association of regional geographers
    • /
    • v.15 no.6
    • /
    • pp.689-706
    • /
    • 2009
  • It is usual to prioritize the spatial variables that influence housing location by a few specialist's experienced knowledge or intuition. Multiple regression techniques were used to evaluate the spatially prioritized relationships between housing density and seasonal solar intensity parameters for a total of 134 house locations. Solar radiation and duration of sunshine on winter solstice was the most important predictor of house density located in intermontane basin. In contrast to the typical theory, elevation, slope and accessibility to road were not a dominant determining factor upon the dependent variable of house density. A clear verification has been made for the hidden assumptions for the arrangement of typical Korean housing in intermontane basin that its approach is found to be more appropriate in avoiding shadow conditions, rather than exploring the ideal landform location.

  • PDF

Effect of nonlinear elastic foundations on dynamic behavior of FG plates using four-unknown plate theory

  • Nebab, Mokhtar;Atmane, Hassen Ait;Bennai, Riadh;Tahar, Benabdallah
    • Earthquakes and Structures
    • /
    • v.17 no.5
    • /
    • pp.447-462
    • /
    • 2019
  • This present paper concerned with the analytic modelling for vibration of the functionally graded (FG) plates resting on non-variable and variable two parameter elastic foundation, based on two-dimensional elasticity using higher shear deformation theory. Our present theory has four unknown, which mean that have less than other higher order and lower theory, and we denote do not require the factor of correction like the first shear deformation theory. The indeterminate integral are introduced in the fields of displacement, it is allowed to reduce the number from five unknown to only four variables. The elastic foundations are assumed a classical model of Winkler-Pasternak with uniform distribution stiffness of the Winkler coefficient (kw), or it is with variables distribution coefficient (kw). The variable's stiffness of elastic foundation is supposed linear, parabolic and trigonometry along the length of functionally plate. The properties of the FG plates vary according to the thickness, following a simple distribution of the power law in terms of volume fractions of the constituents of the material. The equations of motions for natural frequency of the functionally graded plates resting on variables elastic foundation are derived using Hamilton principal. The government equations are resolved, with respect boundary condition for simply supported FG plate, employing Navier series solution. The extensive validation with other works found in the literature and our results are present in this work to demonstrate the efficient and accuracy of this analytic model to predict free vibration of FG plates, with and without the effect of variables elastic foundations.

A Study on the Consistency of Socially Responsible Consumer Attitudes and Behaviors toward Environment Problem (환경문제에 대한 사회책임적 소비자태도와 행동의 일관성에 관한연구)

  • 심미영
    • Journal of Families and Better Life
    • /
    • v.16 no.3
    • /
    • pp.123-140
    • /
    • 1998
  • The purpose of this study was to investigate the consistency of socially responsible consumer attitudes and behaviors toward environment problem. The major findings were as follows; 1. The socially responsible consumer behaviors toward environment problem were classified into resource conservation purchasing & using in green product and recycling behavior by factor analysis. 2. Correlation coefficient of the socially responsible attitudes and behaviors toward environment problem was found to be above. 43. This result implies that the consistency of socially responsible attitudes and behaviors was very high. 3. In the area of total socially responsible consumer attitudes and behaviors toward environment problem the related variable on the consistency of attitude and behavior were altruism perceived power of big business liberalism alienation dogmatism perceived consumer effectiveness faith on the environmental regulation policy experience of environment education and consumer i formation.

  • PDF