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Numerical Investigation of Convective Heat Transfer and Friction in Solar Air Heater with Thin ribs

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Computer Modeling in Engineering & Sciences 2018年第3期114卷 295-319页

作者： Sanjay K.Sharma V.r.Kalamkar VNIT Nagpur

The three-dimensional numerical investigation of an incompressible flow through rib roughened solar air heater is carried out.A combination of thin transverse and truncated ribs is attached on the absorber plate to study its effect on the heat transfer and friction *** parameters in the form of reynolds number(re)of 4000-16000,relative roughness pitch(P/e)of 8-18 and relative roughness height(e/Dh)of 0.0366-0.055 is considered for the *** CFD code ANSYS FLUENT is used to solve the governing equations of turbulent *** rNG k-εturbulence model is used to solve the transport equations with enhanced wall treatment,keeping the Y+ratio of the Nusselt number and friction factor obtained is 1.91 and 3.61 *** detailed investigation on average heat transfer,friction factor and flow structures have been discussed.

关键词： CFD 3D heat transfer friction factor

Low-cost remote rain and Stream Data Acquisition System for Mapping of Potential Micro-Hydro Sites

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Energy and Power Engineering 2013年第4期5卷 56-62页

作者： r. C. Pallugna A. b. Cultura C. M. Gozon N. r. Estoperez Mindanao State University - Iligan Institute of Technology Mindanao University of Science and Technology

The stream and rain data acquisition system presented in this paper makes the mapping of hydro potentials in the region or of the country economically and practically possible. Moreover, it can also serve as a flood w... 详细信息

关键词： Stream Data Acquisition Micro-hydro Flood Warning System

Anodic oxidation of formic acid on PdAuIr /C-Sb2O5·SnO2 electrocatalysts prepared by borohydride reduction

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燃料化学学报 2014年第7期42卷 851-857页

作者： A. O. Neto J. Nandenha r. F. b. De Souza G. S buzzo J. C. M . Silva E. V. Spinacé M . H. M . T. Assumpo Instituto de Pesquisas Energeticas e Nucleares-IPEN-CNEN/SP Cidade UniversitCtria Sao Paulo 05508-900 Brazil

PdAuIr/C-Sb2O5·SnO2electrocatalysts with Pd∶Au∶Ir molar ratios of 90∶5∶5,70∶20∶10 and 50∶45∶5 were prepared by borohydride reduction *** electrocatalysts were characterized by EDX,X-ray diffraction,transmission electron microscopy and the catalytic activity toward formic acid electro-oxidation in acid medium investigated by cyclic voltammetry(CV),chroamperometry(CA)and tests on direct formic acid fuel cell(DFAFC)at 100℃.X-ray diffractograms of PdAuIr/C-Sb2O5·SnO2electrocatalysts showed the presence of Pd fcc phase,Pd-Au fcc alloys,carbon and ATO phases,while Ir phases were not *** micrographs and histograms indicated that the nanoparticles were not well dispersed on the support and some *** cyclic voltammetry and chroamperometry studies showed that PdAuIr/C-Sb2O5·SnO2(50∶45∶5)had superior performance toward formic acid electro-oxidation at 25℃compared to PdAuIr/C-Sb2O5·SnO2(70∶20∶10),PdAuIr/C-Sb2O5·SnO2(90∶5∶5)and Pd/C-Sb2O5·*** experiments in a single DFAFC also showed that all PdAuIr/C-Sb2O5·SnO2electrocatalysts exhibited higher performance for formic acid oxidation in comparison with Pd/C-Sb2O5·SnO2electrocatalysts,however PdAuIr/C-Sb2O5·SnO2(90∶5∶5)had superior *** results indicated that the addition of Au and Ir to Pd favor the electro-oxidation of formic acid,which could be attributed to the bifunctional mechanism(the presence of ATO,Au and Ir oxides species)associated to the electronic effect(Pd-Au fcc alloys).

关键词： PdAuIr/C—Sb2O5·SnO2 甲酸氧化燃料电池电力

Inverse Length biased Maxwell Distribution:Statistical Inference with an Application

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Computer Systems Science & Engineering 2021年第10期39卷 147-164页

作者： Amer Ibrahim Al-Omari Ayed r.A.Alanzi Department of Mathematics Faculty of ScienceAl al-Bayt UniversityMafraqJordan Department of Mathematics College of Science and Human Studies at Hotat SudairMajmaah UniversityMajmaah 11952Saudi Arabia

In this paper,we suggested and studied the inverse length biased Maxell distribution(ILbMD)as a new continuous distribution of one *** ILbMD is obtained by considering the inverse transformation technique of the Maxwell length biased *** characteristics of the ILbMD such as the moments,moment generating function,mode,quantile function,the coefficient of variation,coefficient of skewness,Moors and bowley measures of kurtosis and skewness,stochastic ordering,stress-strength reliability,and mean deviations are *** addition,the bonferroni and Lorenz curves,Gini index,the reliability function,the hazard rate function,the reverse hazard rate function,the odds function,and the distributions of order statistics for the ILbMD,are *** ILbMD parameter is estimated using the maximum likelihood method,the method of moments,the maximum product of spacing technique,the ordinary and weight least square procedures,and the Cramer-Von-Mises *** Fishers information,as well as the rényi and q-entropies,are *** investigate the usefulness of the proposed lifetime distribution and to illustrate the purpose of the study,a real dataset of the relief times of 20 patients receiving an analgesic is used.

关键词： Maxell distribution inverse length biased Maxwell distribution Fisher’s information methods of estimation goodness of fit tests

respiratory neuroplasticity following carotid body denervation Central and peripheral adaptations

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Neural regeneration research 2012年第14期7卷 1073-1079页

作者： Matthew r. Hodges Hubert V. Forster Department of Physiology Medical College of Wisconsin Milwaukee WI 53226 USA Neuroscience research Center Medical College of Wisconsin Milwaukee WI 53226 USA Zablocki Veterans Affairs Medical Center Milwaukee WI 53226 USA

Historically, the role of the carotid bodies in ventilatory control has been understated, but the current view suggests that the carotid bodies （1） provide a tonic, facilitory input to the respiratory network, （2） serve as the major site of peripheral 02 chemoreception and minor contributor to CO2/H＋ chemoreception, and （3） are required for ventilatory adaptation to high altitude. Each of these roles has been demonstrated in studies of ventilation in mammals after carotid body denervation. Following carotid body denervation, many of the compromised ventilatory ＂functions＂ show a time-dependent recovery plasticity that varies in the degree of recovery and time required for recovery. respiratory plasticity following carotid body denervation is also dependent on species, with contributions from peripheral and central sites/mechanisms driving the respiratory plasticity. The purpose of this review is to provide a summary of the data pointing to peripheral and central mechanisms of plasticity following carotid body denervation. We speculate that after carotid body denervation there are altered excitatory and/or inhibitory neuromodulator mechanisms that contribute to the initial respiratory depression and the subsequent respiratory plasticity, and further suggest that the continued exploration of central effects of carotid body denervation might provide useful information regarding the capacity of the respiratory network for plasticity following neurologic injury in humans.

关键词： control of breathing chemoreception, carotid body denervation ventilation plasticity

Self-deception can evolve under appropriate costs

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Current Zoology 2015年第2期61卷 382-396页

作者： Juan Camilo rAMirEZ James A. r. MArSHALL Department of Computer Science University of Sheffield Sheffield S 1 4DP United Kingdom

Apparent biases in decision making by animals, including humans, seem to present an evolutionary puzzle, since one would expect decisions based on biased （unrealistic） information to be suboptimal. Although cognitive biases are hard to diag- nose in real animals （Marshall et al., 2013b）, we investigate Trivers＇ proposal that individuals should self-deceive first in order to better deceive others （Trivers, 2011）. Although this proposal has been scrutinized extensively （bandura et al., 2011） it has not been formally modelled. We present the first model designed to investigate Trivers＇ proposal. We introduce an extension to a re- cent model of the evolution of self-deception （Johnson and Fowler, 2011）. In the extended model individuals make decisions by taking directly into account the benefits and costs of each outcome and by choosing the course of action that can be estimated as the best with the information available. It is shown that in certain circumstances self-deceiving decision-makers are the most evolutionarily successful, even when there is no deception between these. In a further extension of this model individuals addi- tionally exhibit deception biases and Trivers＇ premise （that effective deception is less physiologically costly with the aid of self-deception） is incorporated. It is shown that under Trivers＇ hypothesis natural selection favors individuals that self-deceive as they deceive others .

关键词： Self-deception Deception Overconfidence Cognitive biases Optimal decision-making Optimal behavior

Determination of Trace Amounts of Vanadium by Kinetic-Catalytic Spectrophotometric Methods

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Chinese Journal of Chemistry 2006年第4期24卷 557-562页

作者： POUrETEDAL, H.r. KESHAVArZ, M.H. Department of Chemistry Malek-ashtar University of Technology Shahinshahr Iran

Kinetic-catalytic spectrophotometric methods were proposed for the determination of trace amounts of vanadium element as vanadium（Ⅳ） and/or V（Ⅴ） ions. The vanadium（Ⅳ） as VO^2＋ ion and/or vanadium（Ⅴ） as VO3^- ion showed a catalytic effect on the kinetic reactions between a color reagent such as methylthymol blue （MTb） or SPADNS and bromate in acidic media. The rate of decrease in the absorbance of the reagent MTb at 440 nm or SPADNS at 510 nm was proportional to concentration of V（Ⅳ） and/or V（Ⅴ） ions in the solution. The linear ranges for determination of vanadium were obtained in the range of 1.0-150 and 5.0-100.0 μg/L by the fixed-time and slope methods, respectively, with using MTb as reagent. In the presence of SPADNS as reagent, the calibration curves were made in the amplitude 1.0-200.0 and 5.0-150 μg/L of vanadium ion by the fixed-time and slope methods, respectively. Using fixed-time method, the limits of detection were obtained to be 0.5 and 0.7 μg/L of vanadium in the presence of MTb and SPADNS as reagents, respectively. Detection limits of vanadium by slope method and reagents of SPADNS and MTb were obtained to be 3.5 and 3.8 μg/L of vanadium, respectively. The proposed methods were applied successfully to determination of vanadium in synthetic and real samples.

关键词： kinetic-catalytic method SPADNS methylthymol blue vanadium

Purchasing Patterns and Consumer Level Waste of Fruits and Vegetables in Urban and Peri-Urban Centers in the Philippines

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Food and Nutrition Sciences 2017年第10期8卷 961-977页

作者： Elda b. Esguerra Dormita r. del Carmen rosa S. rolle Postharvest Horticulture Training and research Center College of Agriculture and Food Science University of the Philippines Los Banos Laguna Philippines Food and Agriculture Organization of the United Nations Rome Italy

Fruits and vegetables are inherently perishable hence they are considered as one of the most wasted categories of food. While several studies have been conducted to assess consumer level waste of fruits and vegetables, few have been conducted in developing countries like the Philippines. A survey, using a pre-tested questionnaire, and involving 500 respondents, was conducted in selected urban and peri-urban areas in the Philippines, to ascertain consumer level fruit and vegetable waste. The quantities of fruits and vegetables wasted by supermarket shoppers and those who purchased fruits in wet markets were comparably low at 3% - 4%. This low level of consumer fruit and vegetable waste was attributed to the small quantities (250 to 500 grams per purchase) purchased by consumers in both categories of markets. Consumer level fruit and vegetable waste, showed a positive correlation to household size. The level of fruit waste was positively related to household income, and negatively related to shopper’s age. Consumers who shopped in supermarkets, purchased larger quantities of fruit when compared to those who shopped in wet markets. Wet market shoppers on the other hand, purchased large quantities of vegetables. Decay, and quality loss manifested by shriveling, wilting, toughening, browning and softening were the main characteristics of fruits and vegetables discarded by consumers. The underlying causes of this waste, cited by respondents included “forgot to eat”, “poor quality”, “forgot to cook” and “overbuying”. Consumer efforts to minimize waste include buying enough for consumption, consuming or using immediately after purchase, planning their menus, improving storage and purchasing produce that is of good quality.

关键词： Fruit and Vegetable Waste Supermarket Wet Market

Influence of pH of spray solution on optoelectronic properties of cadmium oxide thin films

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Journal of Semiconductors 2015年第3期36卷 29-34页

作者： r.M.Hodlur M.K.rabinal Department of Physics Karnatak University

Highly conducting transparent cadmium oxide thin films were prepared by the conventional spray pyrolysis technique. The pH of the spray solution is varied by adding ammonia/hydrochloric acid. The effect of pH on the morphology, crystallinity and optoelectronic properties of these films is studied. The structural analysis showed all the films in the cubic phase. For the films with pH 〈 7（acidic condition）, the preferred orientation is along the（111） direction and for those with pH 〉7（alkaline condition）, the preferred orientation is along the（200） direction.A lowest resistivity of 9.9×10^4 cm（with carrier concentration D5.1×10^20cm^3, mobility D12.4 cm^2/（V s））is observed for pH12. The resistivity is tuned almost by three orders of magnitude by controlling the bath pH with optical transmittance more than 70%. Thus, the electrical conductivity of CdO films could be easily tuned by simply varying the pH of the spray solution without compromising the optical transparency.

关键词： spray pyrolysis pH cadmium oxide thin films electrical conductivity