bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of shading to the output power of photovoltaic in Indonesia
Authors: Ramadhan U F , Apriansyah M E , Alvianingsih G , Utomo A R
Published: December 2019

Indonesia, being a tropical country, has a high photovoltaic (PV) energy generation potential that can help meet demand due to the impending shortage of power supplies in the coming years. The shading effect is a negative effect that causes the Photovoltaic power output to drop from its normal state. The performance of Photovoltaic Panels (PV) is a shared module surface exposed to sunlight. Shading effects usually occur from the influence of clouds, but the influence of these clouds often causes a lack of uniform illumination of sunlight received by the photovoltaic. This is also often called Partial Shaded. Partially shaded PV systems cannot operate at maximum efficiency because of shadows cast by surrounding structures, foliage and cloud cover. This is done to see the effect of partial shading pattern effect on solar cell PV. Characteristics of I-V can be influenced by pattern shading effect. The voltage and current of PV solar cells will drop from partial shading effect experiment which consists of 20%, 40%, 60%, 80% and 100% shading area.
The usability of the educational board game for learning english
Authors: Soewardi H , Perdana M F
Published: December 2019

English is the most widely spoken languages in the world and used as an international communication. The importance of English proficiency is the primary reason for people to be motivated in English learning. Such learning process requires a learning facility to help achievement the learning goals. One of the English learning facilities is board game which has been developed in the previous study. However, the usability of this board game design as media in teaching-learning process remains unproven since it needs a reliable testing. This study aims to analyze the usability of educational board game design developed based on effectiveness, efficiency, and satisfaction parameter. Usability test was conducted using performance measurement method and the system of usability scale questionnaire was distributed to more than 30 respondents of elementary education level at the fourth, fifth, and sixth grade. Experimental study was done in the elementary school to collect the required data. Statistical analysis was applied to test the hypothesis. Result of this study shows that the usability of developed educational board game design is valid for the learning process of elementary school students at 5% significance level with usability level of 85% for effectiveness, 83% for efficiency, and 71% for satisfaction.
The design of cold chain risk management system of frozen tuna product in Aceh using fuzzy logic
Authors: Sastra H Y , Sentia P D , Asmadi D , Afifah M
Published: December 2019

Frozen tuna is a perishable product that sensitive to temperature changing, therefore a good cold chain system is needed. As a part of the supply chain, cold chain system aims to maintain the temperature of the product in order to keep its quality from upstream to downstream. There are various problems encounter the cold chain process that effected to the streamline. In consequence, it is important to build a continuous improvement to reduce the risk in the cold chain. The aims of this research are to discover the risk that can be found on the cold chain process, what is the causes, and the connection between both risks and its causes. This matter to develop risk management system on frozen tuna products in Aceh. This research using House of Risk (HOR) method to capture the most critical risk and risk management system is carried out Fuzzy Inference System (FIS) by Mamdani approach. The results of risk evaluation using HOR phase 1 show that there are 2 risks from 20 existing agents and 33 risk events that must be managed with the risk management, namely human errors and temperature during initial handling that is not according to standard.
Design analysis of raw materials inventory on TC1118 cloth products with JIT approach
Authors: Rimawan E , Mardono U , Kustiadi O , Lutfi M A , Saraswati I
Published: December 2019

Control of inventory of raw materials becomes an important part of the manufacturing process. By controlling good raw materials will reduce storage costs in warehouses, increase productivity and profits of the company. In this paper use quantitative methods that will result in the calculation of the most efficient order quantity to increase the productivity. Based on the just-time approach, control of raw material inventory is done by planning the purchase of raw materials by using the right delivery system so as to produce short delivery time. By ordering one day and added with proper inventory calculation will result in a reorder point in accordance with the company’s production capacity and able to reduce the storage of raw materials in the warehouse. The impact of the implementation of just in time, storage of raw materials in the warehouse becomes less and reduce inventory cost by 9.4%, so as to generate greater profit the company and can make savings of Rp7.581.515.237.
Analysis and information system designs of surveillance infection control system in the hospital
Authors: Sugarindra M , Risdiana N , Rosa E M
Published: December 2019

Almost of infection diseases transmitted in a hospital by medical divides. Until now there is no surveillance system that can store data about system infections in hospitals. This study aims to analyse and identify the design of information systems in hospitals. The method used is using Rapid Application Development (RAD). The results of this study consist of the duties and functions of health workers in the surveillance system as well as data that needs to be known when conducting surveillance. Conclusion in this study was identifying the duty of health workers as users and data that needs to be taken in conducting surveillance.
Comparison of PID and fuzzy logic to control the motions of robotic prosthetic limbs
Authors: Widhiada I W , Budiarsa I N , Widiyarta I M , Coglitore T
Published: December 2019

Prosthetic limbs are one of the tools that can be used for people with lower limb disabilities. The bionic leg is one of the breakthroughs in which its movements can be regulated by the implementation of a control system on the microcontroller. Testing is done by interfacing with Matlab / Simulink on the prototype using the PID control system and the Fuzzy Logic control system with a time of 10s at a reference angle of 90°. The PID control system design is done by auto-tuning to get the required parameters, kp, ki, and kd while the Fuzzy Logic control system by determining the input and output parameters and its rules. The PID parameters obtained were 2 KP, 18 KI, and 0.5 KD while the Fuzzy Logic is the reference signal input and voltage of the DC motor as the output. The motion data obtained from the transient response is the maximum overshoot, percentage error, and settling time from both of the control systems, as for the PID 6.90%, 3.69%, and 0.877s respectively and 3.31%, 3.46%, and 0.610s respectively for the Fuzzy Logic control system. The prototype performance with the Fuzzy Logic control system is better than using the PID control system.
Improved value of temperature different on climatic chamber climatic chamber for thermal conditions
Authors: Sukamto D , Gloriant F , Siroux M
Published: December 2019

Climatic chamber machine at Climatherm laboratory was used for thermal test on wall model. This climatic chamber machine allows the measurement of different environmental variables. In this research, thermal performance tests were conducted on wall model imposing boundary condition vary the cavity distance between two wall elements and then these tests were performed in steady-state conditions. Wall model prepared from aluminum composite and was maintaining controlling the air temperature difference between the two chambers 20°C and the air debit constant. In the first part of this paper, a description of the climatic chamber machine, operation ranges, and theoretical work principles of the climatic chamber are presented. Then, the second part shows the results for the thermal test on wall model. The thermal test performed with the climatic chamber machine allows simulating environmental conditions accurately during in certain distance of cavity and specific air debit. As a result, the configuration settings value at the climatic chamber machine has to correction to reach the air temperature difference as planned. The air temperature difference at the beginning of the thermal conditions on wall model is less than the planned air temperature difference. However, this correction value of temperature shows agreement result with the value 20°C in temperature different.
Development of brake lining based on mountain stone and shellfish waste
Authors: Suriadi I G A K , Atmika I K A , S Komaladewi A A I A
Published: December 2019

In general, brake pads made from asbestos, when used asbestos brake lining have a negative impact on health and the environment. In this research, a hybrid composite brake lining was developed with reinforcement of mountain stone powder, shellfish powder, and alumina with a certain composition. This paper describes the compression strength and water absorption ability of hybrid composite brake linings developed, as an alternative to brake pads that have good mechanical properties and are environmentally friendly. Hybrid composite brake lining material is made in seven weight fraction compositions through a sintering process. The test method is carried out by an experimental method based on ASTM E 9-89a for compression strength testing and based on ASTM D 570-98 for water absorption. The results showed that there was an influence of weight fraction on each composite variation on the compression strength of the brake lining. Reduction of percentage of mountain stone in each composition resulted in varying compression strength values, with the highest compressive strength value in specimen A of 0.1350 kN/mm2 and the lowest in specimen G of 0.0883 kN/mm2. Then the highest water absorption of the brake pad specimen made is 0.041558%, still lower than the asbestos brake lining pads.
Effect of activation time the chicken feather activated carbon on surface area of pores: Candidate for hydrogen storage application
Authors: Partuti T , Alhamidi A , Ardiansyah M Y
Published: December 2019

The use of renewable energy such as hydrogen gas as fuel is still very lacking due to difficulties of its storage. Hydrogen storage material is focused on developing porous material. Chicken feather is one of the organic wastes that can be used as porous activated carbon. The chicken feather activated carbon made in powder and briquette form. The activation process was carried out physically with variation in time 30, 60 and 90 minutes, temperature 500 °C and flow rate of nitrogen 0.3 l/minute. The carbon content from carbonization of chicken feathers is 62.85% using ultimate analysis. The activated carbon analysis with Brunauer-Emmett-Teller (BET) show that surface area for powder sample before activation is 0 m2/g and with activation time 30, 60 and 90 minutes is 79.28 m2/g, 128.28 m2/g and 332.49 m2/g, respectively. The surface area for briquette sample before activation is 20 m2/g and with activation time 30, 60 and 90 minutes is 741.37 m2/g, 150.55 m2/g and 162.65 m2/g, respectively. The Scanning Electron Microscope (SEM) results show that pores appear on the briquette sample are much more and more visible than the powder sample. The pore surface area of the briquette sample is inversely proportional to the increase of activation time. The longer the activation time the pore surface area of the briquette sample decreases. While for powder samples vice versa.
Effect of stored energy on corrosion fatigue properties of ultrafine grained Fe-20%Cr steel by equal channel angular pressing
Authors: Rifai M , Miyamoto H
Published: December 2019

Corrosion fatigue properties of ultrafine grained (UFG) Fe-20%Cr steel by equal channel angular pressing was investigated in term of grain refinement and stored energy. The corrosion fatigue life of the ECAP processed and the post-ECAP annealed sample was analysed. Under annealing temperature of 773 K, due to the recrystallization stage, there was a little difference in microstructure from the four passes ECAP. After the annealing process, the strength of the samples pressed four passes decreases, while the elongation showed more ductile. Two mechanisms for crack propagation have been well recognized for stainless steel. One is slipping step dissolution mode. In this model, the slip step formed by active dislocation at a crack tip is anodic dissolution reaction, so that crack tip advance to further distance. The other is stress adsorption mechanism. The corrosion fatigue cracks initiation and cracks propagation process of iron-chromium alloy can be characterized by corrosion pits and intergranular fracture, respectively. The corrosion fatigue behaviour of non-equilibrium and equilibrium grain boundary of iron-chromium alloy was occupied by crack initiation.
The effect of heat energy on/of iron direct reduction process
Authors: Milandia A , Juniarsih A , Muadz R , Sactianto A , Suryana
Published: December 2019

Direct Reduction is one of the process to converted iron ore into metallic iron. The conversion of iron oxide into metallic iron occurs through saveral stages of intermediate phase. This intermediate phase included of hematite, magnetite and wustite. Iron ore direct reduction is the process involved high temperature because temperatures will provide heat energy. Sufficient heat energy will ensure all stages of converted phase completely reacted. To analyze heat energy inside of the specimen. Ansys software was utilized to simulated iron ore direct reduction process. This simulation using agglomerate spherical and cylindrical form. Temperatures simulation take place at 973 into 1373 Kelvin for 30 and 60 minute. This simulation also simulated carbon monoxide (CO) as reduction gas at 1 atm. According to simulation spherical pellet in the diameter 3 requires higher energy to convert iron oxide into metallic iron.
Stability Improvement by Reducing Voltage Fluctuation using SVC in Penetration Wind Power System
Authors: Siswanto A , Gunadin I C , Said S M , Suyuti A
Published: December 2019

Currently, wind energy is a renewable energy that is growing because some of its advantages are connected to the grid system. This study is focus on presenting a probabilistic theory to design power system stability (PSS) and excitation of the FACTS system controller generator via Static Var Compensator (SVC) connected to wind turbines in Sidrap, region of South Sulawesi system. The purpose of the test system is on oscillation, profile voltage and influence stability of wind turbine penetration. An oscillating system requires system performance compensation from the side of the machine via PSS and transmission via SCV to increase the depth of the electro mechanical mode. So, the simulation results on 44 buses in the South Sulawesi system show the stability of the system and rapid voltage improvement and can reduce the oscillation that occurs. This system is tested using a time domain-based PSAT software simulation on the system.
Monthly Rainfall Prediction Using Statistical Downscaling with Combination of Grid Boxes and Adaptive Neuro Fuzzy and Inference System in Lombok
Authors: Safril A , Ulfiana A
Published: December 2019

Lombok is an island in Indonesia that has more people live in this area. Flood is a natural disaster that cause severe impact on society. To manage the risk of natural disaster, seasonal prediction of rainfall for early warning system are needed. However, prediction is difficult to predict due to El Niño and La Niña. Seasonal prediction of rainfall using Global Circulation Model (GCM) is useful to capture rainfall variability, but has a lack information because it has coarse of grid resolution (more than 200 kilometers). This model cannot provide in the local area so statistical downscaling model is used to get detail information. To optimize the result of prediction from global model, a method to capture the extreme condition is needed. Taking a best predictor that will be used to predict the rainfall is done to get the high performance of model used Singular Value Decomposition (SVD). ANFIS (Adaptive Neuro Fuzzy and Inference System) is a model prediction to capture the rainfall variability. Predictor is chosen based on the physical condition of atmosphere and ocean that have impact on Lombok Region. Selected area of predictor (atmospheric variable) are grid boxes in the Maritime Continent (80°E - 150°E and 12.5°N – 12.5°S) and Nusa Tenggara (105°E - 120°E, 10°S - 0). Eight variable predictors are used for prediction, they are air temperature at 2 m (T2M), geopotential height at 500 mb (Z500), zonal and meridional wind at 850 mb (U850 and V850) and at 200 mb (U200 and V200), sea level pressure (SLP), and air temperature at 850 millibar (T850). Both predictor variables (grid box combination) are used to predict for lead time one month. The result of research shows that rainfall prediction can capture the rainfall variability (correlation 0.70) with RMSE (Root Mean Square Error) is 69.
The Effect of Hanging Sheet Pile Breakwater’s Draft Relative on Wave Transmission Coefficient (Kt) in Irregular Wave
Authors: Paotonan C , Umar H , Baeda A Y , Rachman T , Hasan W
Published: December 2019

Breakwater is a structure that builds parallel to the coast, and located within some distance from the coastline. The breakwater that is currently and widely used is Rubble Mound Breakwater; a large dimension coastal structure with also come in high price. Due to this matter, a Hanging Sheet Pile type breakwater can be one of good solution. This research was conducted at Ocean Technology Laboratory, Faculty of Engineering, Universitas Hasanuddin, in a flume thank with 1:25 model scale, and equipped with wave generator and probes as measurement apparatus. The purpose of this study is to identify the effect of wave parameters (Hi/gT2) and structure parameters (draft relative, s/d) on fluctuated wave transmission coefficients produced. The waves are in the form of irregular waves that generated using JONSWAP spectrum. There were 5 variations in wave height (H) and wave period (T), while variations of structure in the form of draft (s) are in 3 variations. The results of this study indicate that the value of Kt will decrease when Hi/gT2 value increase; so that the greater the value of s/d, the smaller value of Kt will be.
Feasibility Study of Biogas from Banana Peel Waste and Livestock Manure Mixture as Renewable Energy Source
Authors: Rahim I R , Lando A T , Sari K , Asriyanti E , Ihsan M
Published: December 2019

Biogas energy can be obtained from waste of domestic, sewage, cattle, market, food industry etc. Banana peels contain chemical compounds such as cellulose, hemicellulose which contain acidic organic compounds that can be used as substrate for biogas production. Purposes of this study are to analyse the characteristics, the composition and the production cost of biogas made of mixtures of banana peel and livestock manure. The study used 6 biogas reactors where each reactor has 19 L capacity with ratio of 1:2.5 for solid and wastewater. The result shows that reactor E2, containing 7.1% of cow and chicken manure and 14.3% of banana peel, produced the highest rate of biogas (91.4%) when compared to other reactors. E4 reactor produced 209 ml of biogas as effective composition, consisting of 2.4% of cow manure, 7.15% of chicken manure, and 19.0% of banana peel. In terms of production cost, E2 reactors have the most effective composition, with the ability to produce 0,000174 m3 of methane by Rp. 5,747 per kg. Biogas made of organic material and livestock manure is relatively less expensive compared to 3 kg of LPG gas with a price of Rp. 18,000. E4 reactor biogas could produce 209 ml with a composition of 357 g of cow manure, 1,071 g of chicken manure, 2850 g of banana peel, 5.355 l of water for livestock manure and 5.355 l of water for banana peel.
Natural Frequencies of Laminated CFRP Square Plates with Slightly Different Material Properties
Authors: Narita Y , Innami N
Published: December 2019

The influence of using different material properties is studied on the natural frequencies of laminated composite square plates composed of recently developed carbon fiber reinforced plastic (CFRP) materials. The plate is symmetrically laminated by thin layers with each layer reinforced by parallel straight carbon fibers. Using the Ritz method in conjunction with the thin plate theory and the lamination theory, the displacements are assumed as finite polynomial functions with the boundary index to accommodate any combination of classical boundary conditions. The material properties are expressed by a set of four elastic constants, and some typical constants are referred from the recent literature. In addition to these sets of constants, a new standard set of discretized constants is proposed to consider the underlying characteristics of the existing constants. In numerical experiment, the convergence study is carried out, and the lowest five natural frequencies are presented in frequency parameters for five sets of classical boundary conditions. Next, for better insight, a new definition of frequency parameters is introduced to promote more physically meaningful comparison, and the influence of using slightly different constants in frequency calculation is clarified for the purpose of deriving approximate frequency formula.
Development of a Shrouded Wind Turbine with Various Diffuser Type Structures
Authors: Klistafani Y , Mukhsen M I
Published: December 2019

The Shrouded wind turbine is an innovative mean to increase power generated by wind turbine. By encompassing the rotor with a diffuser structure, it is possible to increase the wind velocity through the turbine up to 1.8 times of free stream velocity. Specifically, this study is numerical simulations that investigate the effect of wind velocity on various diffuser type structures to develop shroud wind turbine. Numerical study was conducted using Computational Fluid Dynamics (CFD) method. A reasonable agreement between the computed results, available experimental data and previous simulation is obtained. The results show that simulation results have good agreement to experimental results. However, Curved diffuser give the best increment of wind velocity (at centreline diffuser) than flat diffuser and others, which is 84.18%, with the maximum velocity was 9.21 m/s. Regarding the velocity contour results, vortex in downstream curved diffuser is bigger than others. Therefore, suction effect on curved diffuser is strongest and can generate positive impact on the wind velocity quality inside the diffuser.
Study on High Temperature Tensile Properties and Microstructure of a Tial-Based Alloys
Authors: Yu Qiqi , Wen Daosheng , Wang Shouren , Xia Dianxiu , Yang Xuefeng , Wang Gaoqi
Published: December 2019

The high temperature tensile test of a Ti-45Al-5Nb alloy was carried out at deformation temperatures of 880 °C and 1000 °C, with strain rates of 0.001 s−1 and 0.0125 s−1, respectively. Scanning electron microscopy (SEM) and electron back scattered diffraction (EBSD) were used to analyse the microstructure of different tensile parts. The results showed that under the deformation conditions of 880 °C / 0.001 s−1 and 880 °C / 0.0125 s−1, the alloy underwent brittle fracture, and microstructure was basically unchanged, compared with the original one. Deformed at 1000 °C/0.001s−1, the alloy exhibited plastic deformation and mixed brittle and plastic fracture. Dynamic recrystallization was the main softening mechanism, and the γ phase and B2 phase contents increased by 6.7% and 190.2%, respectively, compared with that deformed at 880 °C/0.0125s−1.
Static and Fatigue Properties of Scarf Patch Repaired Composite Laminates: An Experimental Study
Authors: Guan Weishi , Su Yuru , Tong Gang
Published: December 2019

In this paper, the static and fatigue properties of prepreg scarf-repaired composite laminates and wet layup scarf-repaired composite laminates are investigated experimentally.The results show that the patch debonding of the specimens with prepreg scarf-repaired is less than that of wet layup scarf-repaired. At the average strength of prepreg scarf-repaired specimens is higher than that of wet layup scarf-repaired.The strength of specimens is heavily influenced by the inflfailure mode. The strength of the specimens with a same fracture surface on the upper and lower surface in test region is highest while strength is slightly decreased when the fracture surface is different on the upper and lower surface, and the strength is lowest when the specimens fail in the clamping area or near the clamping area Fatigue has little effect on the specimen stiffness, failure strain, failure strength, debonding of repaired patch and failure mode of specimens.
Research on China’s export cross-border e-commerce ecosystem: a case study of Dunhuang Network
Authors: Zuo Yanan
Published: December 2019

With the development of cross-border electronic commerce, the main body involved is also increasing. This paper studies the ecological system of China’s export cross-border e-commerce from the perspective of ecological chain, and analyzes the relationship between China’s export cross-border e-commerce enterprises, enterprises and the environment. Through the analysis of DHgate, the sixth online foreign trade transaction e-commerce website in the world, this paper points out that the service community is the basis for the expansion of the cross-border e-commerce ecosystem, and the close connection between the trading community and the supporting community determines the velocity of the material and energy cycle of the ecosystem, and there is a symbiotic relationship between the trading, service and supporting community. Finally, this paper puts forward the preliminary idea of the formation of export cross-border e-commerce ecological Circle, which provides the direction for the follow-up research.
Design Method of Jacket Foundation for Tidal Current Turbine
Authors: Jia Fayong , Chu Jingchun , Yuan Ling , Pan Lei , Wang Ting
Published: December 2019

Nowadays, it is a main utilizing mode to generate electric power using tidal current energy, which has been getting rapid development worldwide. Jacket foundation, as a main foundation type, plays an important role to ensure the safety of the tidal current turbine. Thus, a design method of jacket foundation for tidal current turbine is a research focus. In the paper, The SACS-Tidal-bladed joint design method combined SACS, a design tool for offshore engineering, with Tidal-bladed, a load analysis tool for tidal current turbine, is put forward. The method mainly consists of three key design cases, namely mode analysis, ultimate limit analysis and fatigue analysis. Moreover, the jacket foundation for a 2×300kW tidal current turbine is designed using the method. Because the results are satisfied to the relevant specifications, the running safety of the 2×300kW tidal current turbine with the jacket foundation can be ensured.
Simulation of Contact Characteristics for Expandable Mechanism of Shelter Based On Multi-Grid Method
Authors: Li Linlin , Jin Wenli , Qi Baoyun
Published: December 2019

With the increasing demands of the diversified expandable shelter and its reliability of structure in modern society, the requirements of the transmission mechanism that affects the deploying and withdrawing of shelter are also getting higher. At present, there are few studies on the mechanical characteristics of its contacts. In this paper, the contact model of the expandable mechanism of shelter under the elastohydrodynamic lubrication (EHL) condition is established based on the multigrid method. The algorithm is implemented on the platform of MATLAB, and effects of the load, velocity and lubricant viscosity on the contact characteristics of the expandable mechanism are analysed. The results show that the performances can be improved by reducing the external load and increasing properly the velocity and lubricant viscosity. The research in this paper can also provide theoretical reference for design of the expandable mechanism of shelter.
Application of Finite Difference Domain Decomposition Method in Heat Conduction in Three-Layer Insulation Suit
Authors: Yang Lizhi , zhang Peng , Cao Jiahao
Published: December 2019

When working in a high temperature environment, people need to wear special clothing to avoid burns. The special clothing is usually composed of three layers of fabric materials, which are referred to as layers I, II and III. Layer I is in contact with the external environment directly. And there is also a gap between the layer III and the skin. We considered this gap as the layer IV. Firstly, it is assumed that heat balance exists between the air layer and the I layer, and between the IV layer and the dummy skin respectively. According to the experimental data of the outer skin temperature of the dummy and the principle of heat transfer, the heat exchange coefficient between the IV layer and the outer side of the skin is 0.0047. Using the heat balance relationship, the inner wall temperature of layer I is deduced, and the heat exchange coefficient between the air and the layer I is 0.0049. Secondly, the boundary conditions of the heat conduction model are obtained based on these heat exchange coefficients. And the one-dimensional heat conduction model of this special clothing is established. Since the medium of each layer of the special clothing is different, the diffusion coefficient of the equation is a piece-wise function. Combined the boundary conditions, we uses the implicit algorithm to obtain the discrete difference equations and ensure the stability of the numerical format. Finally, the temperature values of different space-time distributions are obtained.
Research on Mechanical Behavior of Prefabricated I-Section Reinforced Concrete Slab Girder
Authors: Li Pengfei , Mao Yan , Dong Zhenhua , Wang Xian
Published: December 2019

Cracks, water seepage and other damage often occurred in the hinge joints of the fabricated hollow slab bridge and affect the transverse integrity of the bridge. In order to solve these problems, a new type prefabricated I-girder is proposed, the girder is connected crosswise through wet joints, and the distributed bars extending from the flange are firmly connected in the wet joints. The wet joint has replaced the hinge joint in the traditional hollow slab structure. Through the static load test of the three-piece fabricated I-section slab girder model, the overall mechanical behavior and the transverse distribution of the load in the fabricated I-section slab girder bridge are studied. Then the dynamic characteristics and overall mechanical properties of the traditional hollow slab girder bridge and the fabricated I-girder bridge with equivalent section was analyzed by MIDAS, consider the influence of shallow hinge joints, middle hinge joints and deep hinge joints. The experimental results are compared with the numerical analysis results, the results show that, under the condition of equivalent section, the overall flexural stiffness and torsional stiffness of the fabricated I-section slab girder structure are greater than that of the traditional hollow slab structure, and the transverse distribution of the load is more uniform, the fabricated I-section slab girder structure has better mechanical performance.
Effect of Mg Doping On Electrochemical Properties Lini1/3Co1/3Mn1/3O2 for High Performance Cathode Material in Lithium Batteries
Authors: Li Lin , Cheng Jinsong , Liu Qing , Wang Ting , Zhao Rongfei
Published: December 2019

The Mg-doped LiNi1/3Mn1/3Co1/3O2 cathode materials have been successfully synthesized via a rheological phase reaction method. The structure and properties of the as-obtained samples were measured by XRD, SEM and electrochemical test methods. Though the Mg-doped samples delivered lower initial capacities, the rate performance and the cycling stability were dramatically enhanced. The Mg2+ doped LiNi1/3Mn1/3Co1/3O2 sample (1%) has the most excellent electrochemical performances, it delivers an initial discharge capacity of 177 mAh g–1 at 0.2 C in the voltage of 2.5–4.5 V, and has a capacity retention of 97.7% after 50cycles.
Study on the Properties of Rubber with Different Contents of Carbon Black
Authors: Li Yi , Zhu Pengxiao , Zhang Qiong , Chen Bo , Zhu Zhifeng
Published: December 2019

In this paper, the rubber with different carbon black content was designed and its properties were tested to verify its effects on rubber properties. The results showed that with the increase of carbon black content, the hardness of rubber increased gradually, and the tensile strength, elongation and tear strength firstly increased and then decreased. The abrasive volume of vulcanization firstly decreased and then increased along with carbon black content. The heat generation of rubber increased slowly between 10 and 20 parts of carbon black content, while the heat generation of rubber increased rapidly between 30 and 40 parts of carbon black content. After thermo-oxidative ageing at 75°C for 96 hours, the hardness, tensile strength, elongation and tear strength of the rubber decreased to varying degrees. The properties of the rubber with carbon black content decreased rapidly between 10 and 20 parts, while the properties of the rubber with carbon black content between 30 and 40 parts decreased slowly.
Improvement of Synthetic Method of Lysine Aspirin
Authors: Chen Kun , Zhu Xin , Tian Qikang , Zhang Lan
Published: December 2019

The synthesis method of lysine aspirin was improved, and the new method was applied to the synthesis of similar new drugs. Aspirin is reacted with an aqueous solution of sodium hydrogen carbonate to prepare its sodium salt, and lysine was reacted with a sodium salt thereof in water to prepare lysine aspirin. The product was identified by melting point, infrared spectroscopy and high performance liquid chromatography; the cysteine salts of aspirin was prepared by this method, and the product was identified by micro melting point apparatus and infrared spectroscopy. Lysine aspirin was synthesized by the reaction of sodium acetylsalicylate with lysine. The author measured the melting point and infrared absorption spectrum of the cysteine salt sample of aspirin, which was initially determined to be possible. The new method offers the possibility to expand the production route of lysine aspirin, and also provides new ideas for the preparation of similar new drugs.
Assembly construction quality detection based on dynamic characteristics of composite component
Authors: Yin Zhen , Qin Lei
Published: December 2019

At present, composite slabs in our country have been widely used. There are few studies on the dynamic characteristics of assembled composite slabs in the existing literature. In this paper, the time history curve and amplitude spectrum of ribbed pre-stressed concrete composite slabs have been measured in the field, and the frequency changes in their dynamic characteristics have been analysed with YSV dynamic signal acquisition and analysis system. The reasons affecting the dynamic characteristics of ribbed prestressed concrete composite slabs are analysed, and the first six modal frequencies of ribbed prestressed concrete composite slabs are obtained, which lays a foundation for the construction quality inspection of ribbed prestressed concrete composite slabs.
Oxidation characterization of M2 powders exposed under humid atmosphere for a long time
Authors: Liu Hengsan , Wang Miaohui , Xu Yifei , Ge Xueyuan , Liang Jinming
Published: December 2019

Atomized M2 powders were stored in an atmosphere of 80% relative humidity for a long time. The oxidation characteristics of atomized alloy powders were analyzed. The results show that the oxygen content of the powders have an increasing trend with the prolongation of storage time under humid atmosphere. The oxygen content of 150-300 mesh coarse powder has a gentle change, and the oxygen content will be reduced to near the original level after drying. The oxygen content of -300 mesh fine powders has a little growth in a short time, but it increases rapidly as time goes on after one week, and increases from 415 ppm to 1098 ppm after four weeks of storage, and the oxygen content of fine powders after drying remained unchanged. Particle size has a great influence on the oxidation characteristics of powders. The smaller the particle size, the greater the oxygen content of the powder. The type of adsorption of oxygen element from coarse powder to fine powder changes from physical adsorption to chemical adsorption.
Investigation on anti-penetration performance of reinforced concrete targets based on ANSYS/LS-DYNA
Authors: Cheng Yi
Published: December 2019

Based on the perforation experiment carried by S.J.Hanchak et al, the finite element method (FEM) model of the reinforced concrete (RC) target was set up. After obtaining the residual velocities of a projectile, the feasibility of this model was verified. On this basis, the effects of the inclination angle and impact position on the penetration resistance of the RC target were analyzed by ANSYS/LS-DYNA. Besides, three targets compared their penetration resistance with the RC target according to residual velocities and target damages. Three main conclusions were drawn: (1) the plastic deformation of the first and third steel layer is intensified with the inclination angle increasing, and the projectile kinetic energy is dissipated more, which improves the penetration resistance of the RC target;(2) the penetration resistance of the RC target is aggravated by the impact position at a high reinforcement ratio (3%), especially when impacting at the crossing point of steel bars;(3) based on the same condition, the anti-penetration performance of four targets is listed as follows: SC target > RC target ≈ SSC target > Concrete target.
Effect of Electron Beam Annealing Duration on the Properties of Zno Thin Films
Authors: Li Yanli , Han Li , Kong Xiangdong
Published: December 2019

The effect of electron beam (EB) annealing duration on the properties of pure ZnO thin films was studied. Pure ZnO precursor films prepared by sol-gel spin coating method were directly annealed by EB for different duration from 20 s to 480 s. The structural, optical and electrical properties were investigated. XRD patterns show (002) preferential growth for all the ZnO films. SEM results reveal that the average grain size changes from ∼10 nm to ∼70 nm with the increase of annealing duration and AFM results show the surface RMS roughness is less than 3 nm. The optical transmittance spectra present the absorption edge of the films is at about 380 nm and the average transmittance is more than 85% in visible region. It’s exciting to find that the ZnO film annealed for only 120 s exhibits resistivity 2×10−2 Ωcm and carrier concentration as high as 5.5×1019 cm−3, which shows an advantage of EB annealing in the preparation of ZnO transparent conductive films.
Study on Preparation and Properties of Unburned Ceramsite With Steel Slag
Authors: Yu Qiaodi , Li Canhua , Wang Zhaoran , Deng Aijun
Published: December 2019

Using steel slag, fly ash and clay as physical materials, cement, expanded perlite and methyl cellulose as additives, the raw materials were ground, bullied, aged, cured and prepared into lightweight and high strength ceramsite. The effects of steel slag, fly ash, clay and cement on the packing density and cylinder compression strength of unburned ceramsite were studied by single factor variable analysis, and the optimum mixing ratio of hot stuffing steel slag, air-quenched steel slag and other raw materials was also studied. Finally, the ratio of fly ash to clay is 40:50:10 and the optimum content of cement is 10%. The content of expanded perlite is 2%. The content of methyl cellulose is 1%. The accumulation density of unburned ceramsite is 943.5kg/m3, and the compressive strength of the tube is 8.153 MPa. Through scanning electron microscope (SEM) and energy spectrum analysis, the microstructure of ceramsite has many small and irregular vitreous composition, most of which are composed of silicate and carbonate. Loose and porous cellular structure is formed between vitreous body and vitreous body, which leads to small volume density of ceramsite.
Synthesis of 1-methyl-3-(5-nitropyridin-2-yl) urea
Authors: Zhang Binliang , Lai Luogen , Feng Pan , Xu Shan
Published: December 2019

1-methyl-3-(5-nitropyridin-2-yl) urea (8) is an important intermediate for small molecule anticancer drugs. A rapid and high yield synthetic method for 1-methyl-3-(5-nitropyridin-2-yl) urea (8) was established in this work. The target compound was synthesized from the commercially available 2-chloro-5 -nitropyridine (5) through multi-step nucleophilic reactions.The structure of the target product was confirmed by 1H NMR. In addition, the synthetic method was optimized. The total yield of the four steps was high up to 92%.
Numberical Simulation and Process Research of Laser Cladding on 738H Injection Mold Steel Surface
Authors: Jia Yunjie , Lou Liyan , Wang Linning , Cai Yujun
Published: December 2019

Laser cladding coating is the focus of development in the field of die repair. It has the characteristics of uniform and compact coating, good bonding strength, little thermal impact on the substrate, and easy to realize automation. FeCr alloy coating was prepared on 738H die steel by laser cladding process. Based on MSC Marc finite element software and life-and-death element method, the numerical analysis model of laser cladding repair was establelished, and the temperature field, stress field and deformation under different process parameters were solved. According to the simulation results, the cladding process was formulated, the hardness and linear thermal expansion coefficient of the cladding coating were characterized, and the effects of the process parameters on the structure and properties of the coating were studied. The cladding coating matched well with the substrate performance was obtained, and the high quality repair of the die surface was realized.
Effects of Solution Heat Treatment on Laves Phase and Corrosion Behaviors in Selective Laser Melted Inconel 718 Alloy
Authors: Zhang Qiang , Li Huixiang , Yang Yousheng
Published: December 2019

Effect of solution heat treatment on microstructure and electrochemical corrosion behaviors were investigated for the selective laser melted (SLM) Inconel 718 superalloy. Electrochemical results showed that solution treatment Inconel 718 has lower corrosion current density and bigger radius of the capacitive loop than as-deposited Inconel 718, means that the solution heat treated Inconel 718 has superior corrosion resistance than as-printed Inconel 718. Microstructure studies suggested that Nb-rich Laves phase widely distributed in the as-deposited Inconel 718 matrix, unlike less Laves phase is exited in annealed Inconel 718. The superior corrosion resistance of the solution heat treatment Inconel 718 could be elucidated by the removed Laves phase.
The Study of Titanium Alloy Precision Casting Turbine Blades Based On Procast
Authors: Dai Hailin , Zhang Chengli , Zhao Qian , Zhu Hang
Published: December 2019

The software ProCAST which is based the Finite Elements Method is used to simulate the process of TiAl casting. Ti-47Al-2Cr-2Nb alloys will be used in the casting. As a result, we have known the characteristic of the alloys, flowage and solidification, and we also have forecast the quantity and distributing of defect in the casting.
Study on Novel Heterogeneous Packaging Material and Housing Design for Spaceborne T/R Module
Authors: Jiang Shouli , Leng Tongtong , Li Jia , Zhong Jianfeng , Gu Yeqing , Wang Richu
Published: December 2019

A novel double-layer structure heterogeneous packaging material SiCp/Al+Si/Al was proposed. The packaging shell of X-band active phased array radar transmit/receive module for aerospace was developed. The deformation control, heat dissipation and anti-mechanical environment analysis of micro-assembly welding process were studied. The test and analysis results show that, compared with conventional materials, it has less deformation in the welding process with low temperature co-fired ceramics printed circuit boards. It has the advantages of laser capping, low expansion, high thermal conductivity and high reliability, and can meet the requirements of spaceborne power module packaging applications.
Design of Parallel Injection Online Compound Control System for Liquid and Water Solvent
Authors: Jiang Xingtong , Wang Zhuo , Bai Xiaoping , Xiong Feng , Li Deqiang
Published: December 2019

The variable spraying technology includes premixed drugs and online mixed drugs. The operators need to be in contact with pesticides in the premixed operation.It is harmful to the operators.Meanwhile it has the disadvantages of large amount of pesticides and environmental pollution. In order to solve this problem, an injection-type online mixed drug spray control system for variable spraying and width control was designed.In this paper, a novel injection-type online mixing pesticide control system is designed to solve this problem for variable spray and width control. The mixing ratio of water solvent flow and the pesticide flow is adjusted in real-time spraying by using a sprayer equipped with the proposed online mixing pesticide control system according to the specific prescription map. The concentration of pesticide at the nozzle is controllable consequently. The real-time dynamic response test and the steady state error test were carried out during the pesticide injection. Results show that the steady state error of the proposed system with using DMC strategy is no more than 5%. The uniformity of the mixed pesticide was tested under different mixing ratios of the system, and the calculated spatial variation coefficient is less than 5%. It shows that the injection-type online mixing pesticide control system has better mixing uniformity.
An Investigation in Phase Transition of MoTe2 Film with Continuous Tellurization Reaction
Authors: Sun Leijie , Ding Manman , Li Jie , Yang Li , Lou Xun , Xie Zijian , Zhang Wenfeng , Chang Haixin
Published: December 2019

Molybdenum ditelluride (MoTe2), as a member of two dimentional transition metal dichalcogenides (2D TMDCs), has been drawing scientists’ attention due to its susceptible phase transition. Here, we studied the phase transition process of MoTe2 with tellurization reaction step by step. In the process of tellurization reaction, the 1T’ MoTe2 would firstly convert to an intermediate phase (1T’@ 2H MoTe2) and then slowly convert to 2H MoTe2 instead of forming a direct phase transition from 1T’ MoTe2 to 2H MoTe2. This result might inspire the phase engineering of other 2D TMDCs and the exploration of potential device design.
Life Prediction of Lubricating Oil Based on GM Model
Authors: Sun Yuanyuan , Wang Yuexing
Published: December 2019

According to the method of testing the life of lubricating oil in the bench test of lubricating oil plunger pump, this paper puts forward the prediction method of lubricating oil life based on the combination prediction model of grey theory and GM model. The method carries out data processing on the original data through gray accumulation generating operation to enhance the regularity of the data; GM is used for prediction, and grey cumulative reduction is used to generate operation reduction data to obtain prediction results. The acid value change data of lubricating oil is selected as the life characteristic information of lubricating oil. The model is used to predict the life of lubricating oil, which solves the problems of less data information and uncertain prediction in one oil change cycle. The model is proved to have high prediction accuracy by posterior difference test.