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American Journal of Operations Research 2024年第1期14卷 74-86页

作者： abdur rashid Md. Amirul Islam Department of Mathematics Jahangirnagar University Dhaka Bangladesh Department of Mathematics Uttara University Dhaka Bangladesh

In operations research, the transportation problem (TP) is among the earliest and most effective applications of the linear programming problem. Unbalanced transportation problems reflect the reality of supply chain and logistics situations where the available supply of goods may not precisely match the demand at different locations. To deal with an unbalanced transportation problem (UTP), it is essential first to convert it into a balanced transportation problem (BTP) to find an initial basic feasible solution (IBFS) and hence the optimal solution. The present paper is concerned with introducing a new approach to convert an unbalanced transportation problem into a balanced one and as a consequence to obtain optimum total transportation cost. Numerical examples are provided to demonstrate the suggested method.

关键词： Unbalanced Transportation Problem (UTP) Supply Demand Initial Solution Optimal Solution

艾滋病病毒流行重组毒株CRF01_AE及其影响

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中国艾滋病性病 2024年第1期30卷 79-83页

作者：李斯斯李康 abdur rashid 贺江珊王沛葭刘茂顺冯毅邵一鸣广西艾滋病防治研究重点实验室公共卫生学院广西医科大学南宁530021 中国疾病预防控制中心性病艾滋病预防控制中心北京102206 南开大学天津300071 北京师范大学北京100875

CRF01_AE作为HIV最主要的流行重组毒株,在全球范围长时序演变,形成区域间的流行特征,构成特色且独立的流行与传播模式,本文从其起源、遗传多样性、流行特征及其对诊断和治疗延迟、疾病进程、治疗效果影响等方面进行综述,阐释CRF01_AE及... 详细信息

CRF01_AE作为HIV最主要的流行重组毒株,在全球范围长时序演变,形成区域间的流行特征,构成特色且独立的流行与传播模式,本文从其起源、遗传多样性、流行特征及其对诊断和治疗延迟、疾病进程、治疗效果影响等方面进行综述,阐释CRF01_AE及时监测对遏制HIV区域间和全球蔓延的作用。

关键词：艾滋病亚型重组流行病学

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Dielectric characteristic of dichlorodifluoromethane(R12)gas and mixture with N_(2)/air as an alternative to SF_(6)gas

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High Voltage 2017年第3期2卷 205-210页

作者： Rahmat Ullah abdur rashid Arooj rashid Faisal Khan Amjad Ali Department of Electrical Engineering CIIT AbbottabadPakistan

In this study,dichlorodifluoromethane(R12)gas and mixtures with nitrogen(N_(2))and air at different pressures and mixing ratios have been investigated and showed good alternative to SF_(6) gas in terms of high-voltage *** gases contain R12 gas,they offer good dielectric properties and possibility to be used in low-temperature *** effects and self-recoverability test have been *** strength under quasi-uniform field showed in the order of SF_(6)>R12>N_(2)>air in alternating current(AC),direct current(DC)and impulse was *** R12/N_(2)(80/20%)could reach over 0.90–0.95 times to that of SF_(6) gas at 50 lb/in^(2) at AC and R12/air(70/30%)gives 0.80–0.90 to SF_(6) gas.R12 gas presents brilliant *** optimal ratio to switch SF_(6) gas is R12/N_(2)(80/20%)and R12/air(70/30%)is based on the authors’experimental condition and setup.

关键词： characteristic mixture mixing

Index model equation analysis:A case study of the risk and source of inorganic contaminants in roadside uncontaminated soil of the Egi oil producing area,Niger Delta

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International Journal of Sediment Research 2023年第6期38卷 891-900页

作者： Elechi Owhoeke Asmat Ali Okorondu Justin Nnaemeka Kingsley John Orie Julius Nkeonyeasua Ehiwario abdur rashid Department of Industrial Chemistry/Petrochemical Technology School of Science Laboratory TechnologyUniversity of Port Harcourt School of Environmental Studies China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Department of Environmental Management Federal University of Technology Owerri Department of Pure and Industrial Chemistry University of Port Harcourt Department of Microbiology Faculty of Life ScienceAmbrose Alli University

This study examined the sources,health risk and pollution status of selected inorganic contaminants such as iron(Fe),nickel(Ni),cadmium(Cd),cobalt(Co),arsenic(As),manganese(Mn),lead(Pb),copper(Cu),zinc(Zn),and chromium(Cr) in representative roadside uncontaminated soil(n=72) from the Egi crude oil mining areas(Oboburu,Obagi,and Ogbogu),Niger Delta,Nigeria,using a combination of multiple models(Principle component analysis(PCA),correlation analysis,geo-accumulation index(Igeo),contamination factor(CF),enrichment factor(EF),pollution load index(PLI),cancer risk(CR),hazard quotient(HQ),and metal daily intake(MDIm)).A random sampling method was applied in the sampling and analysis using inductively coupled plasma mass *** result revealed that the mean(mg/kg) for Oboburu,was the highest for Fe(89.95 ± 28.83) and Mn(26.12 ± 7.642),whereas Obagi,had less Fe(28.90 ± 7.601) and Mn(16.80 ± 5.021),and Ogbogu,Fe(44.67 ± 28.15) and Pb(19.38± 8.731) was the second highest heavy *** order of contamination was F> Mn> Zn> Pb> Cu> Cr> Ni> Cd> *** Igeo and CF had cadmium as a metal of *** contamination level was low from the PLI *** EF revealed anthropogenic sources for all the metals except for Ni,which was *** correlations at p <0.05 and p <0.01 showed much positive significance amongst the *** of the cumulative percentages,loading percentages,and eigenvalues from the regression plot gave a coefficients of determination(r2) of 0.9936,0.9995,and 0.9994,*** PCA indicated that Cd and Ni were of anthropogenic origin;Mn,Fe,and Co were biogenic or natural,and Zn and Pb were of mixed *** CR assessment indicated a possible cancer risk due to Cr,Cd,and Ni,and the rest of elements have no carcinogenic *** findings suggest there should be regular monitoring,source control,and integrated environmental management of the study area.

关键词： Soil Source identification Health risk Carcinogenicity Variability

Redundant Transmission Control Algorithm for Information-Centric Vehicular IoT Networks

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Computers, Materials & Continua 2023年第8期76卷 2217-2234页

作者： abdur rashid Sangi Satish Anamalamudi Mohammed SAlkatheiri Murali Krishna Enduri Anil Carie Mohammed AAlqarni Department of Computer Science College of Science and TechnologyWenzhou-Kean UniversityWenzhou325060China Department of Computer Science Engineering SRM University APAmaravati522502India Department of Cybersecurity College of Computer Science&EngineeringUniversity of JeddahJeddahSaudi Arabia Department of Software Engineering College of Computer Science&EngineeringUniversity of JeddahJeddahSaudi Arabia

Vehicular Adhoc Networks(VANETs)enable vehicles to act as mobile nodes that can fetch,share,and disseminate information about vehicle safety,emergency events,warning messages,and passenger ***,the continuous dissemination of information fromvehicles and their one-hop neighbor nodes,Road Side Units(RSUs),and VANET infrastructures can lead to performance degradation of VANETs in the existing hostcentric IP-based ***,Information Centric Networks(ICN)are being explored as an alternative architecture for vehicular communication to achieve robust content distribution in highly mobile,dynamic,and errorprone *** ICN-based Vehicular-IoT networks,consumer mobility is implicitly supported,but producer mobility may result in redundant data transmission and caching inefficiency at intermediate vehicular *** paper proposes an efficient redundant transmission control algorithm based on network coding to reduce data redundancy and accelerate the efficiency of information *** proposed protocol,called Network Cording Multiple Solutions Scheduling(NCMSS),is receiver-driven collaborative scheduling between requesters and information sources that uses a global parameter expectation deadline to effectively manage the transmission of encoded data packets and control the selection of information *** results for the proposed NCMSS protocol is demonstrated to analyze the performance of ICN-vehicular-IoT networks in terms of caching,data retrieval delay,and end-to-end application *** end-to-end throughput in proposed NCMSS is 22%higher(for 1024 byte data)than existing solutions whereas delay in NCMSS is reduced by 5%in comparison with existing solutions.

关键词： Caching data dissemination redundancy control ICN-vehicular IoT networks

Response of Wheat to Tillage Plus Rice Residue and Nitrogen Management in Rice-Wheat System

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Journal of Integrative Agriculture 2014年第11期13卷 2389-2398页

作者： Khalid Usman Ejaz Ahmad Khan Niamatullah Khan abdur rashid Fazal Yazdan Saleem Ud Din Department of Agronomy Faculty of Agriculture Gomal UniversityD. I. Khan 29050 Pakistan Cotton Research Station Ratta KulachiD. I. Khan 29050 Pakistan Arid Zone Research Institute Ratta KulachiD. I. Khan 29050 Pakistan Oil Seed Research Program National Agricultural Research CentreIslamabad 44000Pakistan

Zero tillage with residues retention and optimizing nitrogen fertilization are important strategies to improve soil quality and wheat （Triticum aestivum L.） yield in rice （Oryza sativa L.）-wheat system. Field experiments were conducted on silty clay soil （Hyperthermic, and Typic Torrilfuvents） in D. I. Khan, Pakistan, to explore the impact of six tillage methods （zero tillage straw retained （ZTsr）, ZT straw burnt （ZTsb）, reduced tillage straw incorporated （RTsi, including tiller and rotavator）, RT straw burnt （RTsb）, conventional tillage straw incorporated （CTsi, including disc plow, tiller, rotavator, and leveling operations）, CT straw burnt （CTsb）） and ifve nitrogen rates, i.e., 0, 100, 150, 200, and 250 kg ha-1 on wheat yield. Mean values for N revealed that spikes m-2, grains/spike, 1 000-grain weight （g）, and grain yield （kg ha-1） were signiifcantly higher at 200 kg N ha-1 in both the years as well as mean over years than all other treatments. Mean values for tillage revealed that ZTsr produced highest number of spikes m-2 among tillage methods. However, grains/spike, 1 000-grain weight, and grain yield were higher in tillage methods with either straw retained/incorporated than tillage methods with straw burnt. Interaction effects were signiifcant in year 1 and in mean over years regarding spikes m-2, 1 000-grain weight, total soil organic matter （SOM）, and total soil N （TSN）. ZTsr produced the most spikes m-2 and 1 000-grain weight at 200 kg N ha-1. ZTsr also produced higher SOM and TSN at 200-250 kg N ha-1 at the end of 2 yr cropping. Thus ZTsr with 200 kg N ha-1 may be an optimum and sustainable approach to enhance wheat yield and soil quality in rice-wheat system.

关键词： wheat yield tillage nitrogen TSN SOM

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Short Response of Spring Wheat to Tillage, Residue Management and Split Nitrogen Application in a Rice-Wheat System

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Journal of Integrative Agriculture 2014年第12期13卷 2625-2633页

作者： Khalid Usman Ejaz Ahmad Khan Fazal Yazdan Niamatullah Khan abdur rashid Saleem Ud Din Department of Agronomy Faculty of Agriculture Gomal UniversityD. I. Khan 29050 Pakistan Oil Seed Research Programme National Agricultural Research Center (NARC) Cotton Research Station Ratta Kulachi D. I. Khan 29050 Pakistan Arid Zone Research Institute Ratta Kulachi D. I. Khan 29050 Pakistan

A ifeld experiment was conducted to study the impact of tillage, crop residue management and nitrogen （N） splitting on spring wheat （Triticum aestivum L.） yield over 2 yr （2010-2012） in a rice （Oryza sativa L.）-wheat system in northwestern Pakistan. The experiment was conducted as split plot arranged in randomized complete blocks design with three replications. Treatments comprised six tillage and residue managements：zero tillage straw retained （ZTsr）, zero tillage straw burnt （ZTsb）, reduced tillage straw incorporated （RTsi）, reduced tillage straw burnt （RTsb）, conventional tillage straw incorporated （CTsi）, and conventional tillage straw burnt （CTsb） as main plots and N （200 kg ha-1） was applied as split form viz., control （no nitrogen＆no splitting, N0S0）;2 splits of total N, half at sowing and half at the 1st irrigation （i.e., 20 d after sowing （DAS））（NS1）;3 splits of total N, 1/3 at sowing, 1/3 at the 1st irrigation, and 1/3 at the 2nd irrigation （NS2）;4 splits of total N, 1/4 at sowing, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation （45 DAS）, and 1/4 at the 3rd irrigation （70 DAS）（NS3）;and 4 splits of total N, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation, 1/4 at the 3rd irrigation, and 1/4 at the 4th irrigation （95DAS）（NS4） as sub plots. The results showed that the most pikes m-2, grains/spike, 1 000-grain weight, grain yield, and N use efifciency （NUE） were obtained at zero tillage, straw retained and 4 splits application of total N （i.e., at sowing 20, 45 and 70 d after sowing）. The results indicated that ZTsr with application of 200 kg N ha-1 in 4 equal splits viz. at sowing 20, 45 and 70 d after sowing is an appropriate strategy that enhanced wheat yield （7 436-7 634 kg ha-1） and N efifciency （28.6-29.5 kg kg-1） in rice-wheat system.

关键词： tillage residue management N split application wheat yield

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Geochemical modeling, fate distribution, and risk exposure of potentially toxic metals in the surface sediment of the Shyok suture zone, northern Pakistan

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International Journal of Sediment Research 2021年第5期36卷 656-667页

作者： Liaqat Alia abdur rashid Seema Anjum Khattak Xubo Gao Shah Jehana Asif Javed National Centre of Excellence in Geology University of Peshawar Department of Earth and Environmental Sciences Bahria University Islamabad School of Environmental Studies China University of Geosciences

The objective of the current study was to assess the contamination of potentially toxic metals(PTMs) in weathered surface sediment, along stream tributaries, and surrounding area of the river Chitral, Shyok suture zone district Chitral, Pakistan. To understand the geochemical features of 113 sediment, samples were collected from the Mirkhani and Drosh area. Then, different statistical tools including the geoaccumulation index(Igeo), cluster analysis(CA), principal component analysis(PCA), and ecological risk assessment(ERA) were used to unravel the origin, intensity, and exposure level of PTMs to control risk and restore the ecosystem within the study area. The results for the PTMs namely nickle(Ni),chromium(Cr), copper(Cu), cadmium(Cd), lead(Pb), zinc(Zn), and cobalt(Co) in Mirkhani and Drosh were in the following ranges: 10 e150, 15 e210, 15 e250, 0.08 e1.00, 10 e70, 76 e240 and 14 e51; and 13 e240, 17 e210, 15 e150, 0.08 e0.60, 7 e140, 47 e150 and 13 e36 mg/kg, respectively. In consequence, the potential ecological risk caused by Pb, Ni, Cu, Co, Cr, and Zn is reflected by the percentages of samples with an ecological risk index(ERI) greater than one which were 100%, 91%, 100%, 100%, 92%, and 100%,respectively. However, the overall mean decreasing order of ecological risk of PTMs in the district Chitral was Pb > Ni > Cu > Co > Cr > Zn > Cd. Moreover, the PCA yielded 78% variability which indicated that mineral prospects play an important role in the contamination of sediment. Furthermore, the mineral phases of Pb and Zn suggested supersaturation, while that for Cd revealed unsaturation. The results of Igeo, ERI, and CA indicated contamination of PTMs in the study area. The ERI value of Pb, Ni, Cu, Co, Cr,and Zn was higher than 1 suggesting an ecological risk in the study area. Moreover, the current study showed the dominance of geogenic contamination with major contributions from ultramafic rock and known mineral prospects. Therefore, contaminated sediment of the

关键词： Geochemical modeling Surface sediment Potentially toxic metals Geoaccumulation index Ecological risk Shyok suture zone

Antimicrobial activities of the rhizome extract of Zingiber zerumbet Linn

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Asian Pacific Journal of Tropical Biomedicine 2011年第5期1卷 409-412页

作者： Golam Kader Farjana Nikkon Mohammad abdur rashid Tanzima Yeasmin Department of Biochemistry and Molecular Biology University of Rajshahi Department of Pharmaceutical Chemistry University of Dhaka

Objective:To investigate antimicrobial effects of ethanolic extract of Zingiber zerumbet(***)(L.)Smith and its chloroform and petroleum ether soluble fractions against pathogenic bacteria and ***:The fresh rhizomes of Zingiber zerumbet were extracted in cold with ethanol(4.0 L)after *** crude ethanol extract was fractionated by petroleum ether and chloroform to form a suspension of ethanol extract(15.0 g),petroleum ether fraction(6.6 g)and chloroform soluble fraction(5.0 g).The crude ethanol extract and its petroleum ether and chloroform fractions were evaluated for antibacterial and antifungal activity against thirteen pathogenic bacteria and three fungi by the disc diffusion *** available kanamycin(30μg/disc)was used as standard disc and blank discs impregnated with the respective solvents were used as negative ***:At a concentration of 400μg/disc,all the samples showed mild to moderate antibacterial and antifungal activity and produced the zone of inhibition ranging from 6 mm to 10 *** the tested samples,the crude ethanol extract showed the highest activity against Vibrio parahemolyticus(***).The minimum inhibitory concentration(MIC)of the crude ethanol extract and its fractions were within the value of 128-256μg/mL against two Gram positive and four Gram negative bacteria and all the samples showed the lowest MIC value against ***(128μg/mL).Conclusions:It can be concluded that,potent antibacterial and antifungal phytochemicals are present in ethanol extract of ***(L.).

关键词： Zingiberzerumbet(L.) Smith Antibacterial Antifungal Minimum inhibitory concentration(MIC) Antimicrobial activity Rhizome Antifungal activity Phytochemicals Disc diffusion method Soluble fraction Pathogenic bacteria

Phytoecological evaluation with detail floristic appraisal of the vegetation arround Malam Jabba,Swat,Pakistan

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 461-467页

作者： abdur rashid Mohammad Farooq Swati Hassan Sher Mohammad N Al-Yemeni Department of Botany University of Peshawar Department of Botany&Biodiversity Conservation University of Swat Department of Botany&Microbiology King Saud University

Objective:To determine the present status of plant communities and their possible association with the habitat in Malam Jabba,Swat,***:A study on the phytoecology was conducted in various ecologically important sites of Malam Jabba,Swat,Pakistan from 2002 to *** altitude of these sites ranged from 1200 m to.1200 *** method was used for evaluation of plants communities and the data on these attributes was converted to relative values. The plant communities were named after 3 leading species with highest importance values. Biological spectrum of the flora based on the life form was prepared by following Raunkiar's life form ***:The floristic composition and structure of the study area were found to be 200 species belonging to 75 ***,Lamiaceae and Poaceae were important families in the study *** biological spectrum showed that therophytic and hemicrytophytic life form and micro-nonophyllous leaf sizes were dominant in the *** air and soil temperatures were decreasing with increasing *** the air and soil temperatures were relatively higher in south slopes than on the northeast *** vegetation analysis of the area indicated eleven plant communities around the *** present vegetation is the relics of moist temperate coniferous forest in the *** communities reflect highly deteriorated conditions. Both the structure and composition of the surrounding vegetation were associated with the types of ***:The conservation of the remaining populations of the reported communities will be best achieved by proper time of sustainable *** is only possible with the participation of local communities.

关键词： Plant communities Altitudinal variation Conservation Slopes Biological spectrum Climatic conditions Phytoecological evaluation Vegetation Floristic appraisal Phytoecology Composition