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Modification of colorimetric method based digital soil test kit for determination of macronutrients in oil palm plantation

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International Journal of Agricultural and Biological Engineering 2020年第4期13卷 188-197页

作者： Muhammad Yamin Wan Ishak bin Wan Ismail Muhamad Saufi bin Mohd Kassim Samsuzana Binti Abd Aziz Farah Naz Akbar Redmond R.Shamshiri Muhammad Ibrahim Benjamin Mahns department of Farm Machinery&power Faculty of Agricultural Engineering&TechnologyUniversity of AgricultureFaisalabad(38040)Pakistan department of Biological and Agricultural Engineering Faculty of EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia department of Allied Health Sciences Sargodha Medical CollegeUniversity of Sargodha(40100)Pakistan Leibniz Institute for Agricultural Engineering and Bioeconomy Max-Eyth-Allee 10014469 Potsdam-BornimGermany department of Environmental Sciences&Engineering Government College University Faisalabad(38000)Pakistan

It is the need of time that oil palm farmers must perform the spatially planned soil analysis to know about the fertilizer sufficient and deficient zones of *** method is a suitable and fast solution of soil analysis for NPK determination using the digital soil test *** determination procedure with a digital soil test kit was undefined for oil ***,the digital soil test kit determines the passage of light through an opaque medium of soil solution with a specified ***,environmental light may interfere leading to wrong results of NPK ***,this equipment was non-incorporable with the controller of any VRT fertilizer *** this research,these issues were addressed and the NPK measurement procedure was defined for oil palm plantation by modifying the‘soil to water’ratio in sample soil solution with an optimum environmental light range of 18-23 W/m^(2).‘Soil to water’ratios were found for nitrogen,phosphorus and potassium as 0.31 to 5.00,1.00 to 5.00 and 4.50 to 5.00,respectively to fit the requirement of NPK for oil palm in the prescribed range of the *** study of modified digital soil test kit showed that 91.7%N,89.6%P and 93.8%K results of modified digital soil test kit were matched with analytical laboratory ***,the reliability of NPK results using digital soil test kit was enhanced,making the kit incorporable with the controller of variable rate fertilizer applicator through remote monitoring based data acquisition *** outcome of this research can be used in the development of an IoT network data fusion for dynamic assessment of the NPK variation in the soil and nutrient management in oil palm plantations.

关键词： digital soil test kit variable rate fertilizer applicator oil palm NPK measurement data acquisition system colorimetric method

Access Control Attacks on PLC Vulnerabilities

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Journal of Computer and Communications 2018年第11期6卷 311-325页

作者： Yong Wang Jinyong Liu Can Yang Lin Zhou Shuangfei Li Zhaoyan Xu department of Information Security Shanghai University of Electric Power Shanghai China Palo Alto Networks California CA USA

In Industrial Control Systems (ICS), security issues are getting more and more attention. The number of hacking attacks per year is endless, and the attacks on industrial control systems are numerous. Programmable Logic Controller (PLC) is one of the main controllers of industrial processes. Since the industrial control system network is isolated from the external network, many people think that PLC is a safety device. However, virus attacks in recent years, such as Stuxnet, have confirmed the erroneousness of this idea. In this paper, we use the vulnerability of Siemens PLC to carry out a series of attacks, such as S7-200, S7-300, S7-400, S7-1200 and so on. We read the data from the PLC output and then rewrite the data and write it to the PLC. We tamper with the writing of data to achieve communication chaos. When we attack the primary station, all slave devices connected to the primary station will be in a state of communication confusion. The attack methods of us can cause delay or even loss of data in the communications from the Phasor Data Concentrator (PMU) to the data concentrator. The most important thing is that our attack method generates small traffic and short attack time, which is difficult to be identified by traditional detection methods.

关键词： ICS PLC PMU Data Tampering Delay Attack Methods

Study on Effect of UHV power Grid Construction Schemes on Short Circuit Current

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Journal of power and Energy Engineering 2015年第4期3卷 200-205页

作者： Zaihua Li Feng Gao Qing Wang Shuang Zhang Hongmei Luo Jian Liang China Electric power Research Institute Beijing China Ningxia Electric power Research Institute Yinchuan China

The commissioning of Southern Hami-Zhengzhou ±800 kV UHVDC transmission project has important significance to heighten operation reliability, transfer capability and supply electric ability of Henan power grid. However, short circuit currents of 500 kV buses in the Center of Henan are almost close to the operation upper limitation. In order to decrease the short circuit currents effectively, it’s necessary to strengthen the network structure of Center of Henan power grid and calculate short circuit currents. Two schemes of strengthening the network structure of Center of Henan power grid are studied. The calculated values of short circuit currents of some important 500 kV buses in the two schemes are still bigger than excepted. According to the latest Plan of State Grid, Yubei UHV substation and Zhumadian UHV substation located in Henan power grid. The calculated values of short circuit currents of some important 500 kV buses with the commissioning of Yubei UHV and Zhumadian UHV are qualified. So, reasonable network structure with UHV is suitable to heighten transfer capability and supply electric ability of Henan power grid.

关键词： UHV UHVDC Construction Scheme Short Circuit Current

Reduction in thermal conductivity of monolayer WS_(2) caused by substrate effect

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Nano Research 2022年第10期15卷 9578-9587页

作者： Yufeng Zhang Qian Lv Aoran Fan Lingxiao Yu Haidong Wang Weigang Ma Ruitao Lv Xing Zhang Key Laboratory for Thermal Science and power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Understanding the substrate and temperature effect on thermal transport properties of transition metal dichalcogenides(TMDs)monolayers are crucial for their future ***,a dual-wavelength flash Raman(DF-Raman)method is used to measure the thermal conductivity of monolayer WS_(2) at a temperature range of 200–400 *** measurement accuracy can be guaranteed in this method since the influence of both the laser absorption coefficient and temperature-Raman coefficient can be eliminated through *** room-temperature thermal conductivity of suspended and supported WS_(2) are 28.5±2.1(30.3±2.0)and 15.4±1.9(16.9±2.1)W/(m·K),respectively,with a~50%reduction due to substrate *** dynamics(MD)simulations reveal that the suppression of acoustic phonons is mainly responsible for the striking *** behaviors of optical phonons are also unambiguously investigated using Raman spectroscopy,and the in-plane optical mode,E(Γ),is surprisingly found to be slightly enhanced while out-of-plane mode,A1g(Γ),is suppressed due to substrate interaction,mutually verified with MD *** study provides a solid understanding of the phonon transport behavior of WS_(2) with substrate interaction,which provides guidance for TMDs-based nanodevices.

关键词： monolayer WS_(2),thermal conductivity,substrate effect,temperature effect,dual-wavelength flash Raman(DF-Raman)method

Deformation pre-compensated optimization design of cam ring for low pulsation hydraulic motors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第2期24卷 130-145页

作者： Chao ZHANG Hao TAN Yu FANG Xiaolong ZHANG Yu YANG Yiman DUAN Min HAN Shaojian CUI Bing XU Junhui ZHANG State Key Laboratory of Fluid power and Mechatronic Systems Department of Mechanical EngineeringZhejiang UniversityHangzhou 310058China Zenmax Hydraulics Co. Ltd.Qinhuangdao 066000China

Cam-lobe radial-piston hydraulic motors are widely used in large machinery due to their excellent capability to withstand high loading at low ***,the line contact between the roller and cam ring generates elastic deformation of the cam ring under high loading,leading to obvious speed and torque pulsations and even the detrimental crawl problem of hydraulic *** address this issue,we propose a deformation pre-compensated optimization design approach to compensate for the cam ring deformation in advance,thereby eliminating the influence of cam ring deformation on the hydraulic motor’s *** this approach,the design process is divided into two steps:first,the overall profile of the cam ring is optimized based on the calculated elastic deformation;second,the local profile of cam ring is further optimized until the hydraulic motor’s pulsations no longer ***,a case study is carried out to verify the effectiveness of this *** result indicates the pulsation rate of a deformation pre-compensated cam ring is 40%lower than that of an uncompensated *** study offers an easy and feasible way to design an optimized cam ring profile for low pulsation hydraulic motors.

关键词： Hydraulic motors Cam ring Deformation pre-compensation Pulsation

Photoelectrochemical degradation of Methylene Blue with β-PbO_2 electrodes driven by visible light irradiation

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Journal of Environmental Sciences 2011年第6期23卷 998-1003页

作者： Guoting Li HoYin Yip Kin Hang Wong Chun Hu Jiuhui Qu Po Keung Wong department of Environmental and Municipal Engineering North China University of Water Conservancy and Electric Power Zhengzhou 450011 China School of Life Sciences The Chinese University of Hong Kong Shatin N.T. Hong Kong SAR China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beifing 100085 China

β-PbO2 electrodes were prepared by electro-deposition and characterized by scanning electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,and linear sweep *** confirmed pure β-PbO2 crystals were on the electrode and it had a high oxygen evolution *** photoactivity and photoelectrochemical（PEC） properties of the β-PbO2 electrode were investigated under visible light irradiation（λ 〉 420 nm） for the decolorization of Methylene *** first-order kinetics parameter（Kapp） for dye decolorization using the β-PbO2 electrode achieved 6.71×10-4 min-1 under visible light irradiation,which indicated its excellent visible light-induced *** Kapp of the PEC process was as much as 1.41×10-3 min-1 and was 1.71 times that of visible light irradiation or electrolysis even in the presence of the β-PbO2 electrode.A significant synergetic effect was observed in the PEC *** also employed TiO2 modified β-PbO2 electrodes in this test,which revealed that the TiO2 immobilized on the β-PbO2 electrode inhibited the visible light-induced PEC efficiency despite the amount of TiO2 used for electrode *** β-PbO2 electrode was also superior to the dimensionally stable anode（Ti/Ru0.3Ti0.7O2） in visible light-induced photoactivity and PEC efficiency.

关键词： photocatalysis photoelectrochemical process visible light β-PbO2 electrode

Application of Risk-based Flexibility Assessment Methods to Evaluate System Expansion Plans

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Energy and power Engineering 2013年第4期5卷 1022-1025页

作者： Baorong Zhou Pei Zhang Jianbin Chen Xiaoming Jin Kai Hou Ming Niu Zhao Xu Yunkai Lei department of Electrical Engineering The Hong Kong Polytechnic University Hong Kong SAR China Electric power Research Institute of China Southern power Grid Guangzhou China Tianjin University Tianjin China

This paper proposed a flexibility assessment approach based on and risk assessment methodology. System planners prioritize each planning scheme with consideration of three aspects: reliability, economics, and flexibility. In the past, there is lack of quantitative indices to measure flexibility of a power system. This paper proposes applying probabilistic risk assessment method to quantify system flexibility. The proposed approach is demonstrated to compare two transmission planning schemes during Guangdong expansion planning process.

关键词： Flexibility Assessment Transmission Scheme Prioritization

Evaluation of On-Line MPPT Algorithms for PV-Based Battery Storage Systems

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Computers, Materials & Continua 2022年第11期73卷 3595-3611页

作者： Belqasem Aljafari Eydhah Almatrafi Sudhakar Babu Thanikanti Sara A.Ibrahim Mohamed A.Enany Marwa M.Ahmed Electrical Engineering department College of EngineeringNajran UniversityNajran11001Saudi Arabia Mechanical Engineering department College of Engineering-RabighKing Abdulaziz UniversityJeddahSaudi Arabia K.A.CARE Energy Research and Innovation Center King Abdulaziz UniversityJeddah21589Saudi Arabia Center of Excellence in Desalination Technology King Abdulaziz UniversityJeddahSaudi Arabia department of Electrical and Electronics Engineering Chaitanya Bharathi Institute of TechnologyHyderabad500075India Electrical power and Machines department Faculty of EngineeringZagazig UniversityZagazig44519Egypt Electrical Engineering department Faculty of EngineeringKing Abdul-Aziz UniversityJeddah80204Saudi Arabia

This paper presents a novel Simulink models with an evaluation study of more widely used On-Line Maximum power Point tracking(MPPT)techniques for Photo-Voltaic based Battery Storage Systems(PV-BSS).To have a full comparative study in terms of the dynamic response,battery state of charge(SOC),and oscillations around the Maximum power Point(MPP)of the PV-BSS to variations in climate conditions,these techniques are simulated in Matlab/*** introduced methodologies are classified into two types;the first type is conventional hill-climbing techniques which are based on instantaneous PV data measurements such as Perturb&Observe and Incremental Conductance *** second type is a novel proposed methodology is based on using solar irradiance and cell temperature measurements with pre-build Adaptive Neuro-Fuzzy Inference System(ANFIS)model to predict DC–DC converter optimum duty cycle to track *** evaluation study is introduced for conventional and proposed On-Line MPPT *** comparative study can be useful in specifying the appropriateness of the MPPT techniques for *** the introduced model can be used as a valued reference model for future research related to Soft Computing(SC)MPPT techniques.A significant improvement of SOC is achieved by the proposed model and methodology with high accuracy and lower oscillations.

关键词： Photo-voltaic based battery storage systems adaptive neuro-fuzzy inference system maximum power point tracking perturb&observe technique incremental conductance technique state of charge

Evaluation of flue gas desulfurization gypsum as a low-cost precipitant for phosphorus removal from anaerobic digestion effluent filtrate

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 198-206页

作者： Yaping Guo Adam Khalaf Wenzhuo Kong Hongzhen Ma Jiawei Liang Dongxu Zhao Zhiguo Wang Yebo Li Fuqing Xu Technology Innovation Center for Land Engineering and Human Settlements Shaanxi Land Engineering Construction Group Co.Ltd and Xi’an Jiaotong UniversitySchool of Human Settlements and Civil EngineeringXi’an Jiaotong UniversityXi’an 710049China department of Food Agriculturaland Biological Engineeringthe Ohio State UniversityColumbusOH 44691USA Shaanxi Environmental Survey and Assessment Center Xi’an 710054China

Land application of anaerobic digestion(AD)effluent as a fertilizer is desirable for nutrient recycling,but often supplies excess phosphorus(P),which contributes to surface water *** the P content in AD effluent filtrate using calcium(Ca)treatment prior to land application is a potential strategy for improving effluent disposal and meeting the discharge *** study took flue gas desulphurization(FGD)gypsum,a by-product of coal-fired power plants,as a low-cost Ca source,and combined with traditional phosphorus removal agents to achieve high phosphorus removal efficiency with less chemical *** the results showed,FGD gypsum dosages of 20 mmol/L Ca(3.44 g/L)and 40 mmol/L Ca(6.89 g/L)removed up to 97.1%of soluble P(initially 102.8 mg/L)within 60-90 *** FGD gypsum treatment with traditional chemical treatments using calcium hydroxide[Ca(OH)2]or ferric chloride(FeCl3)could achieve>99%P removal with reduced chemical *** study demonstrated that FGD gypsum is an efficient calcium-based precipitant for phosphorus removal,offering a cost-effective and sustainable approach to enhance wastewater treatment practices and meet discharge standards in wastewater management.

关键词： flue gas desulfurization gypsum anaerobic digestion effluent precipitation phosphorus removal eutrophication