Proceedings of the Pakistan Academy of Sciences: Part A最新文献

筛选
英文 中文
Modeling and Intelligent Controller Design for Reactor Regulating System of Advanced CANDU Reactor (ACR-700) in LabVIEW 先进CANDU反应器(ACR-700)反应器调节系统的LabVIEW建模与智能控制器设计
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-11-26 DOI: 10.53560/ppasa(59-4)783
A. H. Malik, Feroza Arshad, A. Memon
{"title":"Modeling and Intelligent Controller Design for Reactor Regulating System of Advanced CANDU Reactor (ACR-700) in LabVIEW","authors":"A. H. Malik, Feroza Arshad, A. Memon","doi":"10.53560/ppasa(59-4)783","DOIUrl":"https://doi.org/10.53560/ppasa(59-4)783","url":null,"abstract":"In this research work, an Advanced CANDU Reactor of 700 MWe rating (ACR-700) is attempted for Reactor Regulating System (RRS) modeling and intelligent controller design. ACR-700 is a state-of-the-art advanced generation-III reactor. The reactor regulating system is modeled with special emphasis on internal and external reactivity devices. ACR-700 is designed with Liquid Zone Control (LZC) Model, Adjuster Banks Model, Absorber Banks Model and Shutdown Banks Model. The RRS model is a highly sophisticated model developed based on the principle of spatial nuclear reactor dynamics. The RRS model is a multivariable model. The spatial reactor dynamics is modeled based on five internal feedbacks and three feedbacks. The original controller design of RRS is comprised of a PID control algorithm. The control design is reattempted with an advanced intelligent algorithm in which the ANFIS controller is used as a modern control design tool. The new ANFIS controller is basically a multivariable controller. All the modeling of RRS is implemented in Visual Basic (VB) Software while the controller is configured in LabVIEW. A special toolkit is designed for the interfacing of Visual Basic and LabVIEW known as VBLAB. The optimization of intelligent controller parameters is carried out by Genetic Algorithm (GA). The GA-optimized intelligent controller is configured with the VB RRS model. All the variable trends are visualized in the VB environment. The proposed closed-loop ACR-700 RRS control system is tested for small perturbation Analysis and power ramp-down transient and found with excellent behavior well within the design limits. The performance of the suggested ACR-700 RRS controller is compared with the existing conventional controller. The performance of the suggested control scheme is marked with reduced oscillations and faster as compared to the existing control scheme.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45455635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Design and Implementation of Low-Cost Data Acquisition System for Small and Medium Enterprises (SMEs) of Pakistan 巴基斯坦中小企业低成本数据采集系统的设计与实现
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-11-24 DOI: 10.53560/ppasa(59-4)784
Muhammad Imran Majid, Ejaz Malik, Tahniyat Aslam, Osama Mahfooz, Fatima Maqbool
{"title":"Design and Implementation of Low-Cost Data Acquisition System for Small and Medium Enterprises (SMEs) of Pakistan","authors":"Muhammad Imran Majid, Ejaz Malik, Tahniyat Aslam, Osama Mahfooz, Fatima Maqbool","doi":"10.53560/ppasa(59-4)784","DOIUrl":"https://doi.org/10.53560/ppasa(59-4)784","url":null,"abstract":"This paper presents the development of low-cost and robust industrial IoT based data acquisition system primarily focused on domestic manufacturing industries striving to achieve goals and benefits of “Industrial 4.0”. This proposes aims to promote DAQ System integration in traditional manufacturing process of the small and mid-sized industries of Pakistan with limited capacity of investment. Proposed method comprises of Arduino and it’s IoT features for Data Collection, along with a self-developed PC based Centralized Software for Collection of Data, Graphical User Display and Storing collected Data in Local SQL Database. PC based Software replaces requirement of multiple software in case of traditional low-cost DAQ systems, like OPC Software for collecting data from industrial hardware, Java or PHP based any GUI and SQL Data storage. The analysis of work is done with the help of the Message Queue Telemetry Transport (MQTT) protocol. This project will be in further stages evaluated to add features of Supervisory Control, along with Data Acquisition hardware with minimum increase in cost and further upgrading PC Software to add more features of Industry 4.0, as compared to costly commercial solutions available in the market. A machine learning algorithm, k-nearest neighbors algorithm has been used to classify sensitive and non-sensitive data for improvising cloud security. K-Nearest Neighbors is also called KNN algorithm which is supervised machine learning classifier.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42148617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Tidal Range Energy Resource Estimation of Khor Kalmat using Geostatistical Modeling 利用地质统计模型估算科尔卡尔马特潮差能源
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-11-23 DOI: 10.53560/ppasa(59-4)666
Mirza Salman, Ambreen Insaf, Baig, Saba Javaid, Umair Abbas, Zaheer Uddin
{"title":"Tidal Range Energy Resource Estimation of Khor Kalmat using Geostatistical Modeling","authors":"Mirza Salman, Ambreen Insaf, Baig, Saba Javaid, Umair Abbas, Zaheer Uddin","doi":"10.53560/ppasa(59-4)666","DOIUrl":"https://doi.org/10.53560/ppasa(59-4)666","url":null,"abstract":"Electrical power generation by tidal energy provides various advantages. The energy is highly predictable, has less impact on ecological pollution and provides an indefinite amount of renewable energy. The countries like Canada, China, Russia, South Korea and France are extensively utilizing tidal sources of energy for the generation of electrical energy. A suitable site (where less construction is required), adequate tidal range and sufficient bathymetry; are the basic requirements for the installation of a tidal power plant however sometimes there is no tidal data available for suitable sites, like Khor Kalmat tidal lagoon in Pakistan. Therefore, the first time study is conducted to assess the tidal energy resources of the naturally blessed lagoon, Khor Kalmat, which is located in the Baluchistan province of Pakistan, by using geostatistical modeling. A geostatistical model is developed to estimate the tidal energy potential at Khor Kalmat by using observed data of five available locations along with the coastal belt of Pakistan. Models are designed by integrating several layers into ArcGIS. These layers include tidal data, satellite metaphors and other physical and socioeconomic layers. After processing of data, digitized models and layers are generated. Five different models have been compared and the best model is carefully chosen to predict the tidal data of Khor Kalmat after validation of the individual model, During the study, it was observed that low head hydro tidal turbine of Venturi-Enhanced Turbine Technology (VETT) is best suited for harnessing tidal energy due to adequate tidal range. Consequently, by means of a bi-directional VETT device, the output power is assessed to be 269.93 MW.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42171385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Gun Detection in CCTV Images using HAAR-Like Features 基于haar特征的CCTV图像中的枪支检测
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-11-22 DOI: 10.53560/ppasa(59-4)749
Sami Ur, Fakhre Rahman, Alam, Wajid Ali
{"title":"Gun Detection in CCTV Images using HAAR-Like Features","authors":"Sami Ur, Fakhre Rahman, Alam, Wajid Ali","doi":"10.53560/ppasa(59-4)749","DOIUrl":"https://doi.org/10.53560/ppasa(59-4)749","url":null,"abstract":"Automated video-based surveillance is an important area of research to assist the security personnel to detect the incident of any abnormal events in the surroundings. The objective of this paper is to develop a framework for automatic gun detection using closed-circuit television (CCTV) images. The methodology presented in this paper involves the development of a framework for automatic gun detection using closed-circuit television (CCTV) images, with the aim of enhancing the surveillance of crime and improving human security. The proposed approach consists of a dataset of CCTV images containing instances of guns, as well as non-gun images for comparison. These images would be used to train the proposed algorithm to recognize and identify guns in future CCTV images. The proposed framework is designed for an indoor environment and uses Haar-like features for gun detection. The proposed system involves the installation of CCTV cameras in a suitable corner of an indoor environment for surveillance. The CCTV cameras capture the scene and the frames of the scene are compared with a predefined dataset for automatic gun detection. The proposed approach draws a bounding box and raises an alarm if it detects a gun in a frame extracted from a captured scene. This provides a visual indication of the presence of a gun, making it easier for relevant authorities to quickly identify and respond to the threat. The proposed system shows promising results in real-time applications and about 90% accuracy has been achieved.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43465566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Determination of Temperature Distribution of Rohri, Sindh using Artificial Neural Network and Regression Analysis 用人工神经网络和回归分析确定信德省罗赫里地区的温度分布
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-11-21 DOI: 10.53560/ppasa(59-4)654
Adeel Tahir, Muhammad Ashraf, Zaheer Uddin, Muhammad Sarim, Syed Masood Raza
{"title":"Determination of Temperature Distribution of Rohri, Sindh using Artificial Neural Network and Regression Analysis","authors":"Adeel Tahir, Muhammad Ashraf, Zaheer Uddin, Muhammad Sarim, Syed Masood Raza","doi":"10.53560/ppasa(59-4)654","DOIUrl":"https://doi.org/10.53560/ppasa(59-4)654","url":null,"abstract":"As time passes, the world is facing the problem of global warming, which results in a rise in average daily temperature. Proper knowledge of temperature distribution and future prediction may help to cope with the situation in the near future. Climate forecasting has gone through various faces; in the early days’ people used to predict the behavior qualitatively. Now environmental scientists have developed a quantitative method for forest climate behavior with certain uncertainties. Empirical models have been developed based on regression analysis to estimate temperature distribution. Two models, linear and non linear, use dew point temperature and relative humidity as independent variables. In addition to regression analysis, Artificial Neural Network (ANN) has been utilized to predict the average daily temperatures of Rohri Sindh, a city in Pakistan in the Sindh province. Both empirical models and ANN estimates are in good agreement with the known values of average daily temperatures.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45988764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Design of Three Level Neutral Point clamped inverter with Fuzzy logic based MPPT for PV applications. 基于模糊逻辑的三电平中性点箝位逆变器的MPPT设计。
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-09-24 DOI: 10.53560/ppasa(59-3)775
Saud Ahmad, Farhan Siddique, Hassan Ullah Khan, Muhammad Sohrab, Tasneem Afeefa
{"title":"Design of Three Level Neutral Point clamped inverter with Fuzzy logic based MPPT for PV applications.","authors":"Saud Ahmad, Farhan Siddique, Hassan Ullah Khan, Muhammad Sohrab, Tasneem Afeefa","doi":"10.53560/ppasa(59-3)775","DOIUrl":"https://doi.org/10.53560/ppasa(59-3)775","url":null,"abstract":"In this paper a solar photovoltaic (PV) system with maximum power point tracking (MPPT) for domestic low power applications. The proposed system contains a PV array which provides electrical power, while a DC/DC converter is incorporated to regulate the power derived from PV panels. Fuzzy logic control (FLC) based MPPT has been proposed. To convert the DC voltages and currents obtained from Solar panels to AC voltages and currents, a Neutral point clamped multilevel inverter is included. Furthermore, harmonics are removed by using the LCL filter. The PV system working, design of the DC/DC Boost converter, Novel MPPT techniques, Multilevel inverter topologies and LCL filter design are explained. Results reveal that the FLC based MPPT has much lesser total harmonic distortion (THD) in the PV system. With this property, FLC possesses faster convergence than the perturb & observe (P&O) and other MPPT techniques.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48293464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Some Studies of Multi-Polar Fuzzy Ideals in LA-Semigroups la -半群中多极模糊理想的若干研究
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-09-22 DOI: 10.53560/ppasa(59-3)609
Fareeha Pervaiz, M. Shabir, M. Aslam
{"title":"Some Studies of Multi-Polar Fuzzy Ideals in LA-Semigroups","authors":"Fareeha Pervaiz, M. Shabir, M. Aslam","doi":"10.53560/ppasa(59-3)609","DOIUrl":"https://doi.org/10.53560/ppasa(59-3)609","url":null,"abstract":"This article’s main goal is to investigate the concept of multi-polar fuzzy sets (MPF-sets) in LA-semi-groups, which is an extension of bi-polar fuzzy sets (BPF-sets) in LA-semigroups. The main objective of this research is to extend certain significant BPF-set results to MPF-sets results. This article introduces the concepts of multi-polar fuzzy sub LA-semigroups, multi-polar fuzzy quasi-ideals, multi-polar fuzzy bi-ideals, multi-polar fuzzy generalized bi-ideals, and multi-polar fuzzy interior ideals in LA-semigroups. This article also discusses a number of fundamental aspects of multi-polar fuzzy ideals, and we use these aspects to define regular LA-semigroups.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42852417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Economical Synthesis of Nitrophenols under Controlled Physical Parameters 控制物理参数下硝基酚的经济合成
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-09-15 DOI: 10.53560/ppasa(59-2)615
S. Hussain, M. A. Ahmad, M. Ahmad, A. Nisar, Amina Asghar, Muhammad Suleman, S. Barkaat, M. Riaz, Muhammad Anis Uddin Nasir
{"title":"Economical Synthesis of Nitrophenols under Controlled Physical Parameters","authors":"S. Hussain, M. A. Ahmad, M. Ahmad, A. Nisar, Amina Asghar, Muhammad Suleman, S. Barkaat, M. Riaz, Muhammad Anis Uddin Nasir","doi":"10.53560/ppasa(59-2)615","DOIUrl":"https://doi.org/10.53560/ppasa(59-2)615","url":null,"abstract":"Current studies were performed to find an economical path for the synthesis of nitrophenols which are plant growth regulators (PGR) and are applied to crops for better agricultural production. The study discourages the involvement of costly surfactants such as CTAB, TBAB, H-β and γ-alumina catalysts in commercial production of nitrophenols. This synthesis requires the lower number of chemicals, less time and does not involve the advance instruments. Phenol and its derivatives were selectively nitrated into o/p nitrophenols economically by controlling only the physical parameters, i.e., dilution of nitric acid, reaction time and reaction temperature. The synthesised products were characterised by RP-HPLC and gas chromatography. The reaction between 98% phenol and 32.5% nitric acid at a temperature of 20°C (±2°C) required only 1 hour for optimum yield (91%) of nitrophenols with 77% ortho and 14% para selectivity and was found to have the most suitable route for economical production. The investigated synthetic path is relatively clean and environmentally friendly as it does not involve catalysts and solvents, like the conventional processes. This process may be adopted for commercialisation and industrial level production of nitrophenols for agricultural purposes.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46368543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fourth Order Iterated Method for Estimating a Single Root of Non-Linear Application Equations using Euler Method 用Euler方法估计非线性应用方程单根的四阶迭代法
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-08-28 DOI: 10.53560/ppasa(59-3)650
Umair Khalid Qureshi, Zubair Ahmed Kalhoro, Sanaullah Jamali
{"title":"Fourth Order Iterated Method for Estimating a Single Root of Non-Linear Application Equations using Euler Method","authors":"Umair Khalid Qureshi, Zubair Ahmed Kalhoro, Sanaullah Jamali","doi":"10.53560/ppasa(59-3)650","DOIUrl":"https://doi.org/10.53560/ppasa(59-3)650","url":null,"abstract":"This article presents an iterated method for estimating a single root of non-linear equations which arises in science and engineering. The order of convergence of the proposed iterated method is four and it is derived from the Euler method and Steffensen method. The fourth-order iterated method works on physical application nonlinear equations and is compared with the fourth iterated method and double Newton Raphson method. The numerical outcome of the proposed iterated method is examined with C++/MATLAB. From the numerical results and graphical representation, it can be observed that the fourth-order iterated method is good accuracy, iteration perception and function evaluation as the assessment of the existing fourth iterated method and double Newton Raphson method for solving non-linear application functions.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49167154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Investigating the Impact of Technology Involvement in Education from Student’s Perspective 从学生角度考察技术参与对教育的影响
Proceedings of the Pakistan Academy of Sciences: Part A Pub Date : 2022-08-23 DOI: 10.53560/ppasa(59-3)788
Muhammad Khateeb Khan, Kiran Sheraz, Umar Sultan, Adil Mushtaq
{"title":"Investigating the Impact of Technology Involvement in Education from Student’s Perspective","authors":"Muhammad Khateeb Khan, Kiran Sheraz, Umar Sultan, Adil Mushtaq","doi":"10.53560/ppasa(59-3)788","DOIUrl":"https://doi.org/10.53560/ppasa(59-3)788","url":null,"abstract":"Technology is a great blessing from God as it makes life easier. It has various facets of life and has a strong impact on living organisms. Modern technologies have a strong impact on our education system. In our study, we investigated the impact of modern technologies in our academic era. A questionnaire was designed and gathered data from both male and female students in the education department of NUML University. There are more than 90 % of students who are interested to use technology to excel in their careers in academia. Students are highly interested to solve complex problems by using search engines including Google and YouTube. Based on our research, there are more than 90 % of students agreed that information technology (IT) helped them to solve problems and improve their grades and skills. Similarly, more than 80 % of students are well aware of the ethical use of online tools and information by providing the proper references to the source to avoid academic misconduct.","PeriodicalId":36961,"journal":{"name":"Proceedings of the Pakistan Academy of Sciences: Part A","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46862254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信