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Casting fluidity,viscosity,microstructure and tensile properties of aluminum matrix composites with different Mg_(2)Si contents

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Rare Metals 2022年第8期41卷 2767-2776页

作者： reza Vatankhah Barenji Department of Industrial Engineering Hacettepe UniveristyBeytepe Campus06800AnkaraTurkey

The effect of Mg_(2)Si amount on the properties of Al-Mg_(2)Si as-cast composites was investigated in this *** with different amounts of Mg_(2)Si(15 wt%,20 wt%and 25 wt%)were fabricated,and the fluidity,viscosity,porosity formation and tensile properties were then *** addition,optical microscope and scanning electron microscope were used for micros tructural studies and *** results reveal that with the amount of Mg_(2)Si increasing,the morphology of the primary Mg_(2)Si becomes irregular,the size of primary Mg_(2)Si increases,fluidity decreases,viscosity increases,and porosity amount *** reason for the higher amounts of porosities is the lower fluidity and higher *** addition,Al-15%Mg_(2)Si shows better tensile properties and higher quality index compared to other ***,the fracture surface of the composite with lower Mg_(2)Si amount reveals more ductile mode than those with higher Mg_(2)Si amount.

关键词： Al-Mg_(2)Si Microstructure Fluidity Tensile behavior Porosity

Assessment of Physico-Chemical and Microbial Quality of Sugarcane Juice Sold by Street Vendors in Three Regions of Bangladesh

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Food and Nutrition Sciences 2024年第4期15卷 263-276页

作者： Nargis Akter Khan Md. Murtaja reza Linkon Munni Akter Md. Alamgir Hossain Md. Mahbubur Rahman Tayeba Khan Md. Abdul Alim Md. Esrafil Department of Food Technology and Nutritional Science Mawlana Bhashani Science and Technology University Tangail Bangladesh Department of Biotechnology and Genetic Engineering Mawlana Bhashani Science and Technology University Tangail Bangladesh

Sugar cane juice is a popular refreshing drink in most part of Bangladesh. It has great taste and health benefits;also it is available most of the public places at reasonable prices which consumed by road side customers including general public, shopping personals, tourists, students. In our country, street vendors crushing sugarcane between roller crusher and sold without any heat treatment or preservative, also served with or without added ice and lemon juice. The study aimed to identify and compare the physico-chemical and microbial quality of sugarcane juice. The chemical qualities of juices including moisture, PH, ash, total soluble solid, total sugar, reducing sugar and titrable acidity were found slightly different in Mymensingh, Gazipur and Narayangonj areas. The highest and lowest value of moisture, ash, PH, total soluble solids, total sugar, reducing sugar and titrable acidity were found in 84.33% - 79.26% (Gazipur-Mymensingh), 0.57% - 0.04% (Mymensingh-Gazipur), 5.9 - 2.9 (Gazipur-Narayangonj), 17.48% - 4.98% (Mymensingh-Narayangonj), 21.9% - 6.56% (Mymensingh-Gazipur), 3.7 - 2.1 (Gazipur-Mymensingh) and 0.523% - 0.007% (Narayangonj-Gazipur) respectively. For microbiological analysis, the total viable count of sugar cane juice in Mymensingh, Gazipur and Narayangonj were ranged from 0.6 × 105 - 43.6 × 105 cfu/ml, 4.6 × 105 - 21.6 × 105 cfu/ml and 3.6 × 105 - 36.6 × 105 cfu/ml respectively, where the permitted value is 1.0 × 104 cfu/ml, whereas the total coliform count was ranged from 0.4 × 105 - 6.4 × 105 cfu/ml, 0.6 × 105 - 8.4 × 105 cfu/ml and 0.00 - 8.4 × 105 cfu/ml, where the permitted value is 100 cfu/ml and total fungal count was ranged from 5.5 × 105 - 56.5 × 105 cfu/ml, 21.5 × 105 - 54.5 × 105 cfu/ml and 32.5 × 105 - 68.5 × 105 cfu/

关键词： Sugarcane Street Vendors Microbial Quality Reducing Sugar

On the Nonorientable Genus of the Generalized Unit and Unitary Cayley Graphs of a Commutative Ring

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Algebra Colloquium 2022年第1期29卷 167-180页

作者： Mahdi reza Khorsandi Seyed reza Musawi Faculty of Mathematical Sciences Shahrood University of Technology P.O.Box 36199-95161ShahroodIran

Let R be a commutative ring and U(R)the multiplicative group of unit elements of *** 2012,Khashyarmanesh et *** the generalized unit and unitary Cayley graph,T(R,G,S),corresponding to a multiplicative subgroup G of U(R)and a nonempty subset S of G with S^(-1)={s^(-1)|s∈S}■S,asthegraphwithvertexsetR and two distinct vertices x and y being adjacent if and only if there exists s∈S such that x+sy∈*** this paper,we characterize all Artinian rings R for which T(R,U(R),S)is *** leads us to determine all Artinian rings whose unit graphs,unitary Cayley graphs and co-maximal graphs are *** addition,we prove that for an Artinian ring R for which T(R,U(R),S)has finite nonorientable genus,R must be a finite ***,it is proved that for a given positive integer k,the number of finite rings R for which T(R,U(R),S)has nonorientable genus k is finite.

关键词： unit graph unitary Cayley graph co-maximal graph projective graph nonorientable genus

Gardaneh Salavat porphyry copper system: Is it about metal endowment or fertility of the porphyritic intrusion?

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Acta Geochimica 2022年第3期41卷 496-514页

作者： Seyyed reza Mashhadi Department of Geoscience Aarhus UniversityHøeghGuldbergs Gade 28000 Aarhus CDenmark

Gardaneh Salavat porphyry copper system is located in the northwest of Iran. It comprises a quartz diorite to diorite porphyritic intrusion that created extensive alteration haloes in the host rocks. Despite all technical considerations, the exploration activities did not yield to ore discovery. As the matter of fact, all of the geological,geophysical, and geochemical characteristics of a porphyry Cu-Au deposit exist but there is no economic mineralization. Detailed examinations suggest that the only reasonable explanation can be related to the infertility or low metal endowment of the porphyritic intrusion. The reasons include(1) anomalous ranges of Cu, Au, and Mo rather than economic ore grades,(2) weakly development of potassic alteration,(3) probably sulfur saturation of magma that occurred before intrusion emplacement in the host rocks, and(4) probably low metal endowment in the regional scale and the lack of known porphyry copper deposits in close neighborhoods. It is tried to test the proposed hypothesis with the introduced fertility indicators based on major and trace element geochemistry. However,current fertility indicators could not prove or reject the proposed hypothesis for Gardaneh Salavat porphyritic intrusion because of the high-K calc-alkaline to shoshonitic nature of the intrusive rocks together with the unavailability of relatively fresh/unaltered samples. This case study is notable to examine because(1) it shows that characterization of fertile from barren intrusions seems to be as important as vectoring towards concealed porphyry copper deposits, especially while dealing with deep exploration targets that are associated with high financial risks, and(2) it highlights the inefficiencies and uncertainties in introduced magma fertility indicators for porphyry copper intrusions. As a result, it is of high importance to conduct an overarching investigation on other possible fertility indicators as a fundamental need for the future of the exploration

关键词： Porphyry Copper Fertility Metal endowment Barren intrusion

Developing a GIS-based rough fuzzy set granulation model to handle spatial uncertainty for hydrocarbon structure classification,case study:Fars domain,Iran

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Geo-Spatial Information Science 2022年第3期25卷 399-412页

作者： Sahand Seraj Mahmoud reza Delavar School of Surveying and Geospatial Engineering University of TehranTehranIran Center of Excellence in Geomatics Engineering in Disaster Management University of TehranTehranIran

It is well agreed that geologic risk occurs during hydrocarbon exploration because diverse uncertainties accompany the entire hydrocarbon system parameters such as the source rock,reservoir rock,trap and seal *** order to overcome such attributes with uncertainties,a number of soft computing methods are *** granules could be provided by the Rough Fuzzy Set Granulation(RFSG)with a thorough quality *** is capable of attribute reduction that has been claimed to be essential in investigating the hydrocarbon *** paper is an endeavor to recommend a Geospatial Information System(GIS)-based model with the aim of categorizing the hydrocarbon structures map consistent with the uncertainty range concepts of geologic risk in the rough fuzzy sets and granular *** model used the RFSG for the attribute reduction by a Decision Logic language(DLlanguage).The RFSG was employed in order to classify hydrocarbon structures according to geological risk and extract the fuzzy rules with a predefined range of *** order to assess the precisions of the fuzzy decisions on the hydrocarbon structure classification,the fuzzy entropy and fuzzy cross-entropy are *** proposed RFSG model applied for 62 structures as the training data,average fuzzy entropy has been calculated as 0.85,whereas the average fuzzy cross-entropy has been calculated *** it can be discerned,just seven structures had cross-entropies greater than 0.1,while three structures were larger than *** is implied that the precision of the proposed model is about 89%.The results yielded two reductions for the condition attributes and 11 fuzzy rules being filtered by the granular computing values.

关键词： Rough fuzzy set granular computing Geospatial Information Science(GIS) petroleum system hydrocarbon structure

Optimal design of double-layer barrel vaults using genetic and pattern search algorithms and optimized neural network as surrogate model

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Frontiers of Structural and Civil Engineering 2023年第3期17卷 378-395页

作者： reza JAVANMARDI Behrouz AHMADI-NEDUSHAN Department of Civil Engineering Yazd UniversityYazd 89195Iran

This paper presents a combined method based on optimized neural networks and optimization algorithms to solve structural optimization *** main idea is to utilize an optimized artificial neural network(OANN)as a surrogate model to reduce the number of computations for structural ***,the OANN is trained ***,the main optimization problem is solved using the OANN and a population-based *** algorithms considered in this step are the arithmetic optimization algorithm(AOA)and genetic algorithm(GA).Finally,the abovementioned problem is solved using the optimal point obtained from the previous step and the pattern search(PS)*** evaluate the performance of the proposed method,two numerical examples are *** the first example,the performance of two algorithms,OANN+AOA+PS and OANN+GA+PS,is *** the GA reduces the elapsed time by approximately 50%compared with using the *** show that both the OANN+GA+PS and OANN+AOA+PS algorithms perform well in solving structural optimization problems and achieve the same optimal ***,the OANN+GA+PS algorithm requires significantly fewer function evaluations to achieve the same accuracy as the OANN+AOA+PS algorithm.

关键词： optimization surrogate models artificial neural network SAP2000 genetic algorithm

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苹果机械化采收发展历程、模式及其技术现状

中国农机化学报 2024年第1期45卷 301-306,329页

作者：马瑞峻陈瑜张小花 Arash Toudeshki reza Ehsani 华南农业大学工程学院广州市510642 仲恺农业工程学院自动化学院广州市510225 Mechanical Engineering Department School of EngineeringUniversity of CaliforniaMercedCA 95434

经过近千年的进化发展,苹果伴随着品种及树形的改良,经历从自然熟落到人工采摘,从辅助工具、辅助收获平台、振动捡拾到智能机器人采收的发展历程及相应的不同的机械化作业模式。介绍苹果机械化采收的发展历程及技术现状、不同收获模式... 详细信息

经过近千年的进化发展,苹果伴随着品种及树形的改良,经历从自然熟落到人工采摘,从辅助工具、辅助收获平台、振动捡拾到智能机器人采收的发展历程及相应的不同的机械化作业模式。介绍苹果机械化采收的发展历程及技术现状、不同收获模式下所使用的机具设备以及不同收获模式所应用的场景与条件,为我国苹果主产区因地制宜地选择适合当地苹果收获作业模式提供借鉴。如人工或机器人采摘适用于苹果鲜售市场,非选择性振动捡拾收获方式适用于苹果的二次加工领域;而为提高机器人的作业效率,需要对苹果树的树形进行结构简化改良,需要考虑农机与栽培农艺的结合。

关键词：苹果机械化采摘采摘模式采摘机器人

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Achieving full grating-lobe-free field of view with low-complexity co-prime photonic beamforming transceivers

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Photonics Research 2022年第5期10卷 I0001-I0008页

作者： AROUTIN KHACHATURIAN reza FATEMI ALI HAJIMIRI California Institute of Technology PasadenaCalifornia 91125USA

Integrated photonic active beamforming can significantly reduce the size and cost of coherent imagers for LiDAR and medical imaging *** current architectures,the complexity of photonic and electronic circuitry linearly increases with the desired imaging *** propose a novel photonic transceiver architecture based on co-prime sampling techniques that breaks this trade-off and achieves the full(radiating-element-limited)field of view(FOV)for a 2D aperture with a single-frequency *** only order-of-N radiating elements,this architecture achieves beamwidth and sidelobe level(SLL)performance equivalent to a transceiver with order-of-N^(2) elements with half-wavelength ***,we incorporate a pulse amplitude modulation(PAM)row-column drive methodology to reduce the number of required electrical drivers for this architecture from order of N to order of √N.A silicon photonics implementation of this architecture using two 64-element apertures,one for transmitting and one for receiving,requires only 34 PAM electrical drivers and achieves a transceiver SLL of-11.3 dB with 1026 total resolvable spots,and 0.6°beamwidth within a 23°×16.3°FOV.

关键词： prime complexity element

Structural optimization of filament wound composite pipes

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Frontiers of Structural and Civil Engineering 2022年第8期16卷 1056-1069页

作者： Roham RAFIEE reza SHAHZADI Hossein SPERESP Faculty of New Science and Technologies University of TehranTehran ***Iran

An optimization procedure is developed for obtaining optimal structural design of filament wound composite pipes with minimum cost utilized in pressurized water and waste-water ***,the short-term and long-term design constraints dictated by international standards are ***,proper computational tools are developed for predicting the structural properties of the composite pipes based on the design architecture of *** developed computational tools are validated by relying on experimental ***,an integrated design-optimization process is developed to minimize the price as the main objective,taking into account design requirements and manufacturing limitations as the constraints and treating lay-up sequence,fiber volume fraction,winding angle,and the number of total layers as design *** developed method is implemented in various case studies,and the results are presented and discussed.

关键词： composite pipes optimization experimental validation computational modeling filament winding