检索结果-南通市图书馆

Conservation status evaluation of Berberis species across the Karakoram Mountain Ranges, Pakistan using IUCN Red List Categories and Criteria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forestry Research 2016年第6期27卷 1385-1390页

作者： Tika khan Imtiaz ahmed khan Abdul Rehman Nisar ahmed Integrated Mountain Area Research Centre Karakoram International University Department of Biological Sciences Karakoram International University Centre of Agriculture Biochemistry and Biotechnology University of Agriculture Faisalabad

Berberis species medicinal plants in Pakistan are endangered, high-value with important eco-cultural, commercial and livelihood roles in mountain communities. To assess the geographical distribution of Berberis species across the Karakoram Mountain Ranges in Pakistan, we used IUCN Red List Categories and Criteria （2001） to calculate the extent of occurrence （EOO, 〈100 km^2） and the area of occupancy （AOO, 〈10 km^2） of Berberis pseudumbellata subsp, pseudumbellata and B. pseudumbellata subsp. gilgitica. Overgrazing and habitat loss were key population- limiting factors. The two subspecies had contrasting responses to temperature, elevation, precipitation and insect susceptibility. B. pseudumbellata subsp, gilgitica is endemic to Gilgit-Baltistan and grows in single-cropping zone （ar- eas 〉 200 m a.s.1.）. Status evaluation revealed that both subspecies meet the criteria set for critically endangered species. Prolonged disregard of its declining population trend might lead to its extinction; therefore, integrated con- servation efforts are necessary.

关键词： Berberis Ecological zonation Critically endangered Extent of occurrence Karakoram Occupation area Spatial distribution

Experimental Investigation on the Performance of Heat Pump Operating with Copper and Alumina Nanofluids

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第3期66卷 2843-2856页

作者： Faizan ahmed Waqar ahmed khan Jamal Nayfeh Mechanical Engineering Department College of EngineeringPrince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia

In the present study,an attempt ismade to enhance the performance of heat pump by utilizing two types of nanofluids namely,copper and alumina *** nanofluids were employed around the evaporator coil of the heat *** nanofluids were used to enhance the heat input to the system by means of providing an external jacket around the evaporator *** the nanofluids were prepared in three volume fractions 1%,2%and 5%.Water was chosen as the base *** performance of the heat pump was assessed by calculating the coefficient of performance of the system when it was operated with and without nanofluid jacket.A significant enhancement in the coefficient of performance was noticed when copper and alumina nanofluids were employed in the ***,the coefficient of performance was found to have a direct relationship with the tested volume *** the highest volume fraction of 5%,the performance of the heat pump was found to enhance by 23%with alumina nanofluid,while for copper nanofluid,a very significant enhancement in performance by 72%was ***,utilizing of nanofluids in heat pumps can be very beneficial towards performance enhancement and the idea can also be extended to other thermal systems such as steam power plant,automobile radiator,industrial heat exchangers and refrigeration systems.

关键词： Nanoparticles copper nanofluid alumina nanofluid heat pump coefficient of performance

Strong interfacial charge transfer between hausmannite manganese oxide and alumina for efficient photocatalysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2021年第5期34卷 147-159页

作者： Aisha Kanwal Shamaila Sajjad Sajjad ahmed khan Leghari Muhammad Naeem khan International Islamic University H-10 IslamabadPakistan Pakistan Institute of Engineering and Applied Sciences Islamabad 44000Pakistan Department of Chemistry Government College of ScienceLahorePakistan

Well crystalline manganese oxide(Mn_(3)O_(4))nanoparticles anchored on gamma alumina(γ-Al_(2)O_(3))have been successfully tailored via a proficient and cost effective chemical process as an efficient material for photo *** indicated the composite formation ofγ-Al_(2)O_(3) and hausmannite structure of Mn_(3)O_(4).SEM and TEM revealed that hetero structure of Mn_(3)O_(4)/γ-Al_(2)O_(3) exhibits an amalgam of aggregated nanoparticles and *** demonstrated the chemical states of binary *** band gap tuning has been performed withγ-Al_(2)O_(3) nanoparticles by assimilating hausmannite Mn_(3)O_(4) particles into flower like microstructure of Al_(2)O_(3).The photoluminescence spectra affirmed the enhancement in charge separation in Mn_(3)O_(4)/γ-Al_(2)O_(3) binary hybrid *** band gap becomes narrow with the increase in concentrations of Mn_(3)O_(4).The narrowing of band gap is concorded with crystalline domains of primary aggregated *** elucidate the mechanism of the photocatalytic activity linear sweep voltammetry was *** results showed that Mn_(3)O_(4)/γ-Al_(2)O_(3) nanocomposite revealed the enhancement in current density as compared to pureγ-Al_(2)O_(3) which confirmed the electron transfer from Mn_(3)O_(4) toγ-Al_(2)O_(3) through the interfacial potential gradient in conduction *** optimum concentration of 6.0%Mn_(3)O_(4)/γ-Al_(2)O_(3) for hybrid structure showed an excellent photocatalytic activity under visible light due to narrow band gap *** degree distribution of Mn_(3)O_(4) nano architects overlying onγ-Al_(2)O_(3) induces a significant synergic effect betweenγ-Al_(2)O_(3) and hausmannite phase of manganese oxide(Mn_(3)O_(4)).This strong interfacial contact betweenγ-Al_(2)O_(3) and Mn_(3)O_(4) endures the quick transfer of photo generated charge carriers across interface.

关键词： Hausmannite Mn_(3)O_(4) Alumina Band gap tuning Interfacial charge transfer Nanomaterials Catalysis

Value-Based Test Case Prioritization for Regression Testing Using Genetic Algorithms

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2023年第1期74卷 2211-2238页

作者： Farrukh Shahzad ahmed Awais Majeed Tamim ahmed khan Department of Software Engineering Bahria UniversityIslamabadCapitalPakistan

Test Case Prioritization(TCP)techniques perform better than other regression test optimization techniques including Test Suite Reduction(TSR)and Test Case Selection(TCS).Many TCP techniques are available,and their performance is usually measured through a metric Average Percentage of Fault Detection(APFD).This metric is value-neutral because it only works well when all test cases have the same cost,and all faults have the same *** APFD for performance evaluation of test case orders where test cases cost or faults severity varies is prone to produce false ***,using the right metric for performance evaluation of TCP techniques is very important to get reliable and correct *** this paper,two value-based TCP techniques have been introduced using Genetic Algorithm(GA)including Value-Cognizant Fault Detection-Based TCP(VCFDB-TCP)and Value-Cognizant Requirements Coverage-Based TCP(VCRCB-TCP).Two novel value-based performance evaluation metrics are also introduced for value-based TCP including Average Percentage of Fault Detection per value(APFDv)and Average Percentage of Requirements Coverage per value(APRCv).Two case studies are performed to validate proposed techniques and performance evaluation *** proposed GA-based techniques outperformed the existing state-of-the-art TCP techniques including Original Order(OO),Reverse Order(REV-O),Random Order(RO),and Greedy algorithm.

关键词： Average percentage of fault detection test case prioritization regression testing and value-based testing value-based test case prioritization genetic algorithms

Achieving Energy Efficiency in Wireless Sensor Networks Using Dynamic Channel Polling and Packet Concatenation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Communications 2021年第8期18卷 249-270页

作者： Shama Siddiqui Anwar ahmed khan Sayeed Ghani Department of Computer Science DHA Suffa UniversityKarachiPakistan Department of Computer Science Institute of Business AdministrationKarachiPakistan Department of Computer Science Sindh Institute of Management&TechnologyKarachiPakistan

There has been a significant interest of researchers to combine different schemes focused on optimizing energy performance while developing aMAC protocol for Wireless Sensor Networks(WSNs).In this paper,we propose to integrate two cross-layer schemes:dynamic channel polling and packet concatenation using a recent asynchronous MAC protocol“Adaptive&Dynamic Polling MAC”(ADPMAC).ADP-MAC dynamically selects the polling interval distribution based on characterization of incoming traffic patterns using Coefficient of variation(CV).Packet Concatenation(PC)refers to combining the individually generated data packets into a single super packet and sending it at the polling ***,the Block Acknowledgement(BA)scheme has been developed for ADP-MAC to work in conjunction with the packet *** proposed schemes have been implemented in Tiny-OS for Mica2 platform and Avrora emulator has been used for conducting *** results have revealed that the performance both in terms of energy&packet loss improves when ADP-MAC is used in conjunction with the additional features of PC&***,the proposed scheme has been compared with a stateof-art packet concatenation primitive PiP(Packet-in-Packet).It has been observed that ADP-MAC supersedes the performance of PiP in terms of PDR(Packet Delivery Ratio)due to better management of synchronization between source and sink.

关键词： energy efficiency concatenation dynamic polling

Towards estimating computer users＇ mood from interaction behaviour with keyboard and mouse

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2013年第6期7卷 943-954页

作者： Iflikhar ahmed khan Willem-Paul BRINKMAN Robert HIERONS Department of Computer Software Engineering University of Engineering & Technology Mardan 23200 Pakistan Interactive Intelligence Group Delft University of Technology Delft 2628B the Netherlands Department of Information Systems and Computing Brunel University West London UB83PH UK

The purpose of this exploratory research was to study the relationship between the mood of computer users and their use of keyboard and mouse to examine the possibility of creating a generic or individualized mood measure. To examine this, a field study （n = 26） and a controlled study （n = 16） were conducted. In the field study, interaction data and self-reported mood measurements were collected during normal PC use over several days. In the controlled study, participants worked on a programming task while listening to high or low arousing background music. Besides subjective mood measurement, galvanic skin response （GSR） data was also collected. Results found no generic relationship between the interaction data and the mood data. However, the re- suits of the studies found significant average correlations be- tween mood measurement and personalized regression models based on keyboard and mouse interaction data. Together the results suggest that individualized mood prediction is pos- sible from interaction behaviour with keyboard and mouse.

关键词： keyboard mouse interaction mood measure computer users programming

A Cost-Efficient Environment Monitoring Robotic Vehicle for Smart Industries

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第4期71卷 473-487页

作者： Arfat Ahmad khan Chitapong Wechtaisong Faizan ahmed khan Nadeem Ahmad Suranaree University of Technology Nakhon Ratchasima30000Thailand University of Engineering and Technology LahorePakistan The University of Lahore LahorePakistan

Environmental monitoring is essential for accessing and avoiding the undesirable situations in industries along with ensuring the safety of ***,inspecting and monitoring of environmental parameters by humans lead to various health concerns,which in turn brings to the requirement of monitoring the environment by *** this paper,we have designed and implemented a cost-efficient robotic vehicle for the computation of various environmental parameters such as temperature,radiation,smoke,and pressure with the help of ***,the robotic vehicle is designed in such a way that it can be dually controlled by using the remote control along with the distant *** addition,contrary to the existing researches,the GSM modules are used to achieve the two-way long distance communication between the robotic vehicle and the distant *** the distant computer,the above-mentioned environmental parameters can be monitored along with controlling the robotic vehicle with the help of Graphical User Interface(GUI).In order to fulfill the given tasks,we have proposed two algorithms implemented at the robotic vehicle and the distant computer respectively in this *** final results validate the proposed algorithms where the above-mentioned environmental parameters can be monitored along with the smooth-running operation of the robotic vehicle.

关键词： Industry 4.0 sensors robotic vehicle distant communication environment monitoring

Flow Injection Chemiluminescence Method for Nalbuphine Hydrochloride in Pharmaceutical Formulations Using Tris(2,2′-bipyridyl)ruthenium(II)Chloride-diperiodatocuprate(III)Reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2021年第3期37卷 629-638页

作者： ahmed khan MUHAMMAD Asghar MOHAMMED Yaqoob MASOOD ahmed Siddiqui SAMAR Ali Department of Chemistry University of BalochistanSariab RoadQuetta87300Pakistan

A sensitive and selective method employing chemiluminescence(CL)coupled with flow injection(FI)is reported for nalbuphine hydrochloride(NAL)assay in pharmaceutical *** enhancement effect of NAL on the CL reaction between tris(2,2′-bipyridyl)ruthenium(II)chloride-diperiodatocuprate(III){Ru[(bpy)_(3)]^(2+)-Cu(III)complex}in acidic medium is used as analytical *** optimal conditions of the CL reaction were sulfuric acid 1.0×10^(−3) mol/L,Ru[(bpy)s]2+7.5×10^(−5) mol/L,Cu(III)/Ag(III)complexes 4.0×10^(−4)/5.0×10^(−4) mol/L,sample loop volume of 120µL and flow rate of 2.5 mL/*** sensitivities of the method in terms of detection(S/N=3)and quantification(S/N=10)limits are 5×10^(−4) and 0.001 ppm(1 ppm=1 mg/L),*** linear response of the instrument in the form of CL intensity with respect to NAL concentration is over the range 0.001-15.0 ppm(R^(2)=0.9999)with relative standard deviation from 0.8%to 3.2%and injection throughput of 120 injection/*** applications of the method include the quantitative analysis of NAL in pharmaceutical injection *** and the average results of the proposed method are not significantly different from the results of a reported method by applying F-and paired student *** most likely CL reaction mechanism is written in accordance with spectrophotometric and CL studies.

关键词： Ru[(bpy)_(3)]^(2+) Cu(III)/Ag(III)complex Chemiluminescence Flow injection analysis Nalbuphine hydrochloride Pharmaceutical

Thulium-Doped Fiber Amplifier for Blue Light Signal Amplification

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Communications 2019年第5期16卷 181-188页

作者： Muhammad Hanif ahmed khan Khushik Chun Jiang State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University

Fluoride-based thulium-doped visible light fiber amplifier(TmVLFA), which can be used to amplify the blue light signal for a visible light communication(VLC) system,is theoretically demonstrated for the first time according to the best of our knowledge. The transition rate equations and power propagation equations are solved to predict the dependence of the gain and noise figure on fiber parameters. The numerical results show that with the pump wavelength 1150 nm and pump power 800 mW, 2.75 m long thulium-doped fiber can amplify blue light(480 nm) signal up to 33.3 dB, and the noise figure is in the range from 3.0 to 3.5 dB. The model and numerical results encourage the use of fiber amplifier in VLC system for blue light amplification to extend the range of VLC.

关键词： Tm-doped visible light fiber amplifier visible light communication fiber amplifier gain noise figure