bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of Website-Based Smart Seminar Application on Islamic Learning (Case Study at Raharja University)
Authors: Hamid Abdul , Arribathi  , Suwarto  , Erliyani Ita , Saryani  , Haris
Published: February 2021

The purpose of this study was to determine and test the effectiveness level of smart seminar application in the learning of Islamic Religion with a case study at Raharja University, Tangerang City, with an experimental approach. The data collection technique uses a test. This study took 74 samples, consisting of 37 control groups, i.e. groups that were not given treatment, or groups that did not use the Smart Seminar application, and 37 students as experimental classes, or groups who were treated were groups who used the Smart seminar application. To test whether the application of smart seminars in the teaching of Islamic subjects is effective, the one-way Analysis of Variance (ANOVA) test is used, but first the distribution data groups must have normality distribution and come from homogeneous data groups. From the normality test table and the homogeneity test table, the Asymp value is obtained. Sig. (2-tailed) 0.318> 0.05 and sig 0.958> 0.05 this shows that the data is normally distributed, and coming from a homogeneous data group it meets the requirements to be continued in the Analysis of Variance (ANOVA) test to test whether there is the effectiveness of the use of the Smart Seminar application in learning Islam at Raharja University. From the ANOVA test results obtained that the calculated F value of 196.236 and a sig value of 0.000 <0.05, this shows that the use of the Smart Seminar Application is very effective in learning Islam at Raharja University. Keywords: Application, Smart Seminar, Learning.
Teaching STEM through play in kindergarten: analysis towards pre-service early childhood teachers preparing the lesson plan
Authors: Rasyid A , Sugandi M K , Gaffar A A , Jatisunda M G , Santoso E , Nahdi D S
Published: February 2021

Integrating science with other disciplines like technology and mathematics supports early childhood have awareness and interest in science and affects their overall school performance further down in their education. The integration is commonly referred to as STEM which is an acronym of science (S), technology (T), engineering (E), and mathematics (M). STEM Education is provided to achieve educational aims that prepare people for future life and the workforce. However, designing a STEM-based learning process needs more attention, moreover carried out in early childhood. This study investigates preparing lesson plan early childhood pre-service teachers teaching STEM through play. The study used the phenomenology approach, qualitative data collection through observation, questionnaires, and interviews. The study involved pre-service early childhood teachers semester VII which has experienced the learning process of the Field Teaching Practices. The results showed that pre-service early childhood teachers when designing learning through games had an awareness that early childhood would provide a greater understanding of science concepts than children who teach science through direct instruction. Further findings show that designing the process of learning science through enjoyable experiences is a very important approach to promote students’ understanding of developing kindergarten science concepts.
Google class activities during COVID 19: learning studies on introductory education courses
Authors: Fadilah F , Amalia R , Mustika F , Jatisunda M G
Published: February 2021

Online-based learning platforms are becoming an important thing to be implemented at the time of this pandemic. Google classroom is one of them. however, the online-based learning process required self-directed learning related to determining goals and ways to make it happen. the purpose of this study was to look at self-directed learning students based on their previous achievements. This research is a pre-experimental research design with a one-shot case study. the results of the study prove that students with good learning achievement get a good self-directed learning scale score as well. Based on ANOVA analysis, one path for each category of high learning achievement is significantly different from the medium category and also different from the low category. students with good achievements tend to have goals and ways to achieve learning.
Learning Numerics Words Through Online Games Learning
Authors: Ying Y , Jureynolds
Published: February 2021

Mandarin numeric words are an important part in learning Mandarin. Mandarin numeric words reflect the types of objects that they follow. Chinese literature students study nouns for four years because sentence construction cannot be separated from nouns. Unfortunately, not all students consider nouns important so that up to the junior year, there are still some errors in using nouns. This research uses questionnaire distribution to 38 sophomore students of Chinese literature who have studied Mandarin for 2 years. Through this research, as many as 89.47% of students say mastery of Mandarin numeric words are important. As many as 81.57% of students feel learning Mandarin numeric words is difficult due to the numbers or words in Mandarin numeric words. As many as 71.05% of students think that the teaching methods of using Mandarin numeric words by lecturers are good. As many as 55.26% of respondents answer that they often doing exercises 量词 since this could help them in learning Mandarin numeric words. From the results of this study, in order to master Mandarin numeric words, students are expected to be given task of summarizing Mandarin numeric words in each lesson and the lecturer also provides the exercises. Exercises kata bantu bilangan bisa dilakukan dengan mendesign online games learning karena pembelajaran online sudah menjadi bagian dalam kehidupan mahasiswa dan pembelajaran melalui games akan memudahkan mahasiswa untuk belajar.
Student’s Prevailing, Confidence, and Drives: Computerized Text Analysis on Self-Description Text
Authors: Apriyanto Sigit , Syah Tansri Adzlan , Nurhayaty Any
Published: February 2021

Using a sample of 26 participants, we asked the students to prepare a text in written self-description at the end of the final path presentation in the sixth semester. One interesting thing is the relationship between personality differences and the types of words that people use. Recent studies covers an observing the relationship between personal qualities and the use of language in creating self-description. Text files are organized for transcription LIWC analysis to calculate the percentage of clout, authentic, and drives that student’s use. The results supported this possibility: LIWC’s clout, authentic, and drives dictionaries can be used as indicators of the student’s prevailing, confidence, motives and needs, we found that when calculated on written text, LIWC scores were connected with language dimension and psychology issues. These findings recommend that LIWC clout, authentic, motives, and needs dictionaries possibly will catch self-reported subjective emotion experience when applied to everyday activities. To enrich students’ confidence, power, motives, and needs toward the psychology issues faced by the students, students should be stimulated to discover the field of psychological processes and linguistic patterns by detecting their emotional and perceptual experiences.
Performance Analysis Using the Supply Chain Operations Reference (SCOR) and AHP Method
Authors: Sutoni Akhmad , Subhan Ali , Setyawan Widy , Bhagyana Fitri Oktavia , Mujiarto
Published: February 2021

This research was conducted to see the performance of P.T. X. Planning assessment is carried out on the performance of the supply chain for the production, warehouse, and shipping of goods. The method used is the Supply Chain Operations Reference (SCOR) andAnalythical Hierarchy Process (AHP). With this method, in addition to looking at performance performance, can also see the location of the metrics that must be improved again and which must be maintained. So the company’s work system will be better. The calculation results will be used as a reference to be able to increase customer satisfaction and will increase company revenue. The results obtained are the highest and lowest values of each Plan, Source, Deliver, and Return metrics. P.T. X performance is Good, with a total calculation result of 80.48.
Preparation of Polyvinyl Chloride/ZnO Composite Ultrafiltration Membrane for Peat Water Treatment
Authors: Putri E. , Sidabutar D. , Putri N.A. , Sakinah S. , Nugroho F.A. , Aryanti P.T.P.
Published: February 2021

In this research, composite polyvinyl chloride ultrafiltration (PVC-UF) membrane was used for peat water treatment. The UF membrane was prepared by mixing polyvinyl chloride (PVC), polyethylene glycol (PEG400), ZnO, acetone, and N-dimethylacetamide (DMAC). The concentration of PVC was varied from 10 to 14 wt.%, while the PEG400 was varied from 0 to 15 wt.%. The concentration of acetone and ZnO was fixed at four (4) wt.% and two (2) wt.%, respectively. Immersion precipitation method was used to form the membrane structure. The experimental results showed that higher humic substance rejection (>50%) was achieved when 12 wt.% PVC and 10% wt.% PEG was added into the polymer solution. The permeate flux of the membrane was above 100 L/m−2h−1.Higher rejection of humic substances was obtained at an operating pressure of 30 psig.
Electrical Energy Alternative of Magnetic Field Around Wire of Power Line
Authors: Liklikwati Yakob , Syafruddin  , Ramady Givy Devira , Lestari Ninik Sri , YS Herawati , Hidayat Rahmad
Published: February 2021

The electricity crisis can hamper various community or industrial activities. Meanwhile, the magnetic field with a high field strength around the wire and along the power line wire that is passed through a large electric current can be used as a new source of electricity with considerable power. For this reason, efforts are needed to utilize the magnetic field to offer an energy crisis solution. This research applies the magnet-electric law to the toroid core transformer to become a power plant. The simulation is carried out on a toroid transformer with an outer diameter of 11cm, 2.5cm thick, 9cm long which is mounted on a 27A current; 220V or 380V 3Ø. The result can be to turn on a 5W-160V or 10W-65V incandescent or 7W-200V LHE lamps. The value of 27A on the wire does not change due to the utilization of the magnetic field around the electric wire. From the analysis of a linear approach to power lines with larger currents up to several kA, a power of several kW can be generated at 220V. To get more power at a voltage of 220V required more toroidal transformers placed along the power line.
Development of Campus Hotspot Network Infrastructure using Peer Connection Queue Method based on Voucher System
Authors: Ramady Givy Devira , Liklikwatil Yakob , Lestari Ninik Sri , Hidayat Rahmad , Sukandi Ganjar Kurniawan , Sufyani Rosyidin
Published: February 2021

The use of wireless technology in today’s infrastructure has taken a very important role in the development of mobile communications. The use of wireless technology through the Wireless Distribution System (WDS) technique has also been widely applied to the hotspot network infrastructure in the campus area. WDS is a method of developing wireless network infrastructure that enables the development of wireless networks to become more extensive. However, distance and placement between access points become very important factors to consider that cause problem when sending data and when receiving data. Implementation of the PCQ method, which is one of the features of the proxy router, is aimed at ensuring the quality and performance of the network in good and optimal conditions. The quality of data services provided is regulated using a system voucher, the user is divided into several segments depending on the chosen service plan. This research begins with the planning stage which consists of design and topology selection, then continues with the design and implementation phase, and ends with the preparation phase. The test result data will then be compared with the standard determined by TIPHON which is 0% loss, 150 ms delay, and jitter under 75 ms.
Modelling and Performance Analysis of Synchronous Reference Frame Phase-Locked Loop for Three-phase Grid-connected PV Generation System
Authors: Masri Syafrudin , Aphieez H , Rosa Susila Jaya Kuncara
Published: February 2021

Due to the introduction of the feed-in tariff policy mechanism in many countries, the grid-connected Photovoltaic (PV) generation system becomes new attractions as it encourages the energy producers to generate and supplies electricity to the grid. The characteristic of the inverter’s voltage waveform, its amplitude, phase-angle and phase sequence are vital parameters for effective PV-grid synchronization. This paper presents a double stage converter, DC-DC boost conversion included to maximum power point tracking (MPPT) is achieved. Second stage DC-AC conversion is achieved using voltage source inverter (VSI). Grid connected synchronization is achieved by using synchronous reference (SRF) base phase locked loop (PLL). A details design and model for each section of the proposed system are also presented. The result shows that the implementation of synchronous reference frame (SRF) with PLL able to good achieved.
2D Detection Model of Defect on the Surface of Ceramic Tile by an Artificial Neural Network
Authors: Mariyadi B , Fitriyani N , Sahroni T R
Published: February 2021

The ceramic tile visual inspection process is divided into three parts: texture classification, color classification, and surface defect detection. In its application in the industry is a difficult process, because it is done manually involving many workers and done in a noisy environment with differences in temperature and humidity. This study emphasized the quality control based on the visual inspection automation system on the detection of a defective type of ceramic surface. The process performed is capturing an image, image processing, feature extraction, training, testing, and classification. In the preprocessing process are image resizing, RGB color conversion, segmentation and feature extraction. Features extraction using Gray Level Co-occurrence Matric (GLCM). The generated feature will be an artificial neural network (ANN) input in training and testing using Matlab 2013a to detect more than one type of surface defect with good accuracy. The artificial neural network training uses backpropagation with network architectures 14 input features, 27 hidden layers, 1 output. The learning rate used 0.001, 75 data training, and 23 data testing. The position and type of defect can be detected with 83% accuracy and error rate of 17%. Maximum time detection 1,06 seconds and minimum time detection 0,1 seconds. therefore by using automation system inspection, inspection error caused humans could be ignored and increased quality and productivity in production.
Utilization Plastic Waste Type PET (PolyEthylene Terephthalate) in the Making of Low-Quality Concrete in the City of Palangkaraya
Authors: Kamaliah  , Handayani Noviyanthy
Published: February 2021

The research about utilization plastic waste type PET (PolyEthylene Terephthalate) especially in fields of civil engineering is not much done in Palangka Raya. Even though every day in Palangka Raya, this type plastic waste is quite large. This type of waste management is still not optimal so that this type of garbage can disturb the environment in Palangka Raya. Therefore research is needed so that plastic waste can be used as civil engineering building materials in the case of a mixture of low-quality concrete. This study aims to determine whether PET (Poly Ethylene Terephthatele) plastic waste can be used as a mixture for low quality concrete in Palangka Raya City and the extent of its effect in the compressive strength of low-quality concrete. This research uses experimental methods in the laboratory. The planned concrete quality is K 225 which is classified as low quality concrete. Testing is carried out in 7, 14, and 28 days. PET plastic waste itself will be used as a substitute for coarse aggregate. The variation in the use of PET type plastic to coarse aggregate weight is 5%, 10%, and 15%. The number of samples for each condition is 3 samples so that the total sample used is 36 units. Concrete compressive strength value decreases with increasing levels of PET plastic waste. Average compressive strength fot variations in the mixture of coarse aggregate PET plastic waste 0% (normal), 5%, 10%, and 15% respectively: 272,40 kg/cm2, 246,27 kg/cm2, 239,82 kg/cm2, dan 206,31 kg/cm2.
Web-based information system sales
Authors: Suwita F S , Sholihat S A , Dewi N P
Published: February 2021

This research aims to make it easier for consumers in buying and selling transactions as well as for sellers to promote various kinds of products that can be reached by consumers without visiting the store. This study used descriptive analysis method by conducting interviews directly with the PD. XYZ store as the case study. The results of this study indicate the design of website sales increase the sale and purchase transactions at the store. A media campaign is needed to increase the attractiveness of buyers. In conclusion, the design of a sales information system can help sellers in promoting products in an effort to increase revenue from the store.
Internet of things for flood and landslide early warning
Authors: Soegoto E S , Fauzi F A , Luckyardi S
Published: February 2021

The purpose of this study is to improve the use of technology for the occurrence of a disaster as a form of anticipation in a disaster-prone area and tourist area. The method used in this research was a descriptive research method where the data obtained from events that occur in a particular region. The results of this study indicate that technological innovation is needed to monitor floods and landslides because based on the data from National Disaster Management Agency (BNPB) on the occurrence of disasters in Indonesia. There are still many areas that prone to natural disasters especially floods and landslides. The important role of the technology is to increase the level of confidence and security of tourists towards the potential for a disaster that occurs and can improve the tourism industry economy.
Implementation of management information system at health agencies
Authors: Soegoto E S , Wardana M E , Oktafiani D
Published: February 2021

The aim of this research is to make the business processes of a health agency especially clinics effective and efficient, by computerizing the system using a website to increase profits and reduce clinic expenditure, especially in the use of paper. The method used in this research was the descriptive method to describe the computerized and automated clinics’ business processes. The result of this research was to identify how far the application of technology to business processes and the benefits of implementing a website-based information system at clinics. This research was conducted to discuss the clinic medical record management system, clinic transactions, and clinic drug management. The results of this research will improve business processes and the clinic’s data management to be more effective and efficient by automating and computerizing the system.
Information system for waste bank savings
Authors: Soegoto E S , Arifin F H , Oktafiani D
Published: February 2021

The purpose of this study is to design an application in savings waste bank management information systems. The management of waste bank includes inputting data on waste savings, calculating waste prices, viewing transaction data, and preparing reports. This research used the observation method by visiting Hijau Lestari waste bank Pasteur unit to obtain the required data related waste savings data. The results of this study indicated that savings waste bank management information system can provide ease in managing and processing data for officers and customers. This research conducting by analyzing the system that runs on the waste bank then develops and designs a proposed system. This research is expected to make it easier for officers and customers to improve waste bank management by utilizing technology.
The Role of Using Gadgets in Facing the Existence of Information Systems in the Tourism Village Community in Cidadap Village Using TAM (Technology Acceptance Model)
Authors: Legiawan M K , Sutoni A , Mujiarto
Published: February 2021

Indonesia is one of the countries crossed by the “ringoffire”, the positive impact of the regionis to make the land fertile so that most of the regions in Indonesia are used as tourist attractions. Cidadap Village is in Campaka District, Cianjur Regency, which has the concept tofa tourist village. That is locate don anarea of 969,699 Ha with adescription of the potential of Natural Resources that can be used as tourist attractions, namely anarea of 79 Ha, 25 Ha of Forest, 554,559 Ha of dryland, 6 rivers and 8 Fruit Springs. While the total population of approximately 5811 people who have an educational background fromelementary schools to tertiary institutionsis approximately 2715 people or about 47% of the community who have an educational background. Inapplying the concept to the Tourism Village, ofcourse the role of technology is very important tin this case is the use of gadgets to provide information to the wider community to find out this potential. But be fore implementing information system technology, it is of course necessary to know in advance how ready the community is in using gadgets in the management of the tourist village. To measure how big the role of the Cidadap Village community is in the use of gadgets to information systems using the TAM (Technology Acceptance Model) model by forming constructs according to the model so as to create a hypothesis that is adapted to the conditions of the community.
Application platform for e-reservation system in traditional show
Authors: Mulyana A , Rusmana D , Rafdhi A A
Published: February 2021

The purpose of conducting this research is an effort to maintain and improve the preservation of Indonesian traditional arts using internet marketplace technology. The method used was literature study and field observations to Sekar Saluyu Art Studio as a provider of traditional arts services. The results of this study explained how the application-based marketplace role, which is named by Kenda application, has improved the economy of Indonesian traditional arts, helped develop, and maintain the preservation of traditional arts by using internet technology platforms to compete against foreign cultures. Advances in information technology are a reason to be able to preserve Indonesian traditional arts so that they are not left behind. For this reason, this effort was built to solve the problems of Indonesian traditional arts in the current information era. Therefore, Kenda App Platform was used to provide solutions to these problems.
An Experimental Study of Overlap Ratio Effect to Savonius water Current Turbine by using Myring Equation for n=1
Authors: Setiawan P A , Indarti R , Ariwiyono N , Yuwono T , Widodo W A
Published: February 2021

This study has been employed experimentally towards Savonius water turbine by using Myring equation for n=1. This work will be varied to overlap ratio of 0, 0.05, 0.1, 0.15, 0.2, 0.25 and 0.3. The overlap ratio of 0 can be called as the conventional turbine using half circle. The experiment is tested in flume tank by 1.1 m of wide and 0.8 m of height and the water velocity 0.22 m/s. The turbine have 0.4 m of height and 0.4 of diameter. This work will be calculated the torque coefficient and the power coefficient. The power coefficient is called the performance coefficient. The results indicated that the best performance coefficient has improved in about 62.83 % at overlap ratio of 0.2.
A New 4-D Multistable Hyperchaotic Two-Scroll System, its Bifurcation Analysis, Synchronization and Circuit Simulation
Authors: Vaidyanathan Sundarapandian , Sambas Aceng , Mujiarto  , Mamat Mustafa , Wilarso  , Mada Sanjaya W.S. , Sutoni Akhmad , Gunawan I
Published: February 2021

A new 4-D hyperchaotic two-scroll system with three quadratic nonlinearities and a cubic nonlinearity is proposed in this paper. The dynamical properties of the new hyperchaotic system are described in terms of phase portraits, Lyapunov exponents, Kaplan-Yorke dimension, symmetry, dissipativity, etc. We also establish that the new hyperchaotic system has multistability with coexisting attractors. As a control application, we use integral sliding mode control for active self-synchronization of the new hyperchaotic systems as master-slave systems. As an engineering application, an electronic circuit design of the new hyperchaotic two-scroll system is developed in MultiSIM, which confirms the feasibility of the system.
Bioaccumulation Of Lead (Plumbum) In Red Tilapia Fish From The Jombor Swamp
Authors: Andasari S D , Styawan A A , Hidayati N , Prasetyanti O N
Published: February 2021

Lead (Plumbum, chemically known as Pb) is a dangerous heavy metal usually found in daily activities, such as fuel. Jombor swamp is located in Krakitan village, Bayat, Klaten. Daily routines by people inside or around the swamp cause a lot of pollution, which came from the waste of floating shops, agricultures, households, and fisheries. The purpose of this research was to analyze lead concentration inside the meat of red tilapia fish (oreochromis sp) in Jombor swamp. This research used an observational method, which means that researchers did not investigate the effect of intervention. The samples were taken with cluster sampling method consisting of 3 clusters. They included north cluster I, east cluster II and south cluster III. 25 grams of samples taken from each cluster, in which the fishes were cultured in Jombor swamp for 3 months with the same size. The analysis was conducted with atomic absorbance spectrophotometer, and the data obtained were processed with computerization spectrophotometry method of atomic absorption and the data are processed with computerization programme to examine the mean and deviation standard. This research found that the median of cluster I was 1,45275 mg/kg, cluster II was 0,3143 mg/kg and cluster III was 0,3129 mg/kg. Conclusion: meat of red tilapia fishes cultured in Culture I Jombor swamp positively contained lead as many as 1,45275 mg/kg with safety limit of 0,2 mg/kg.
INDHCI: Indonesian Districts Health Care Information Model
Authors: Kristiadi Dedy Prasetya , Hasanudin Muhaimin , Sutrisno  , Jawahir  , Sudarto Ferry , Tarmizi Rasyid
Published: February 2021

Indonesia as the fourth most populated country in the world has inadequate informaton health care treatment. Moreover, the health index of the population of Indonesia is still relatively low compared to other countries. Medical record for example, no national medical record health information systems integrated which answer challenges to decision making services soon. Provincial health office no have medical record data which doctor need and adequate of information system for decision making to medical action. Indonesian district healthcare information based on raspberry (INDHCI) will be started of Indonesian district and concern in hospitals service healthcare, doctor and patient can communication. Will be built collaboration on district where need to integrate all hospitals healthcare data such as medical record, health facility for hospitals service data medical record collection with public and private community health center and the ministry of health of the Republic of Indonesia. The development will implement current technology such as Near Field Communication or NFC is the development of Bluetooth and RFID in which NFC provides communication technologies using Bluetooth to connect and RFID as a wave to connect to other NFC devices. NFC allows mobile phones to store necessary data safely and reliably. The data can be sent to other phones using NFC or read by an NFC reader. Then data can be save on Data Warehouse. Data can be used as Indonesian district health care information, Indonesian health research by institution and decision Support System by doctor to serve patient any where. The Indonesian district healthcare Information Model will be built in smartphone application, using the Internet of Things (IoT).
Design of a scanning thermocouple inhomogeneity
Authors: Nugraha Heri , Prajitno Prawito , Achmadi Aditya , Tistomo Arfan Sindhu , Larassati Dwi , Imaduddin Agung
Published: February 2021

Inhomogeneities are known to develop within thermoelements exposed to elevated temperatures, resulting in temperature measurement errors and reduced energy efficiency. During process, it is important to determine how much the inhomogeneities affect the measurement result. Thermoelectric inhomogeneity is important factor of the calibration for budget uncertainty calculation. It is normally assessed by gradual, insertion of a thermocouple into a furnace or liquid bath. But, the length that can be scanned by using this equipment typically limited. It need an equipment to scan more length of wire thermocouple to see characteristic of thermocouple. This paper described development design double gradient method for measurements of inhomogeneities in type K and T thermocouples with various diameter and temperature scanning using hot air that can produce heating process up to 600 °C with some sensor to detection real temperature output from hot air source. Therefore, an equipment with a short, movable heating zone to scan along the thermocouple while both the measuring and reference junctions using ice bath are kept at 0 °C. The design of the equipment system was focused on measuring the stability of hot air and controlling the movement of the stepper motor control using a microcontroller. Interpretation of the measurement results and calculation of inhomogeneity using movable heating zone of type K and T thermocouples of the uncertainty budget is presented.
An Aggressive Implementation Method of Branch Instruction Prefetch
Authors: Sun Yufeng , Yuan Yidong , Li Weili , Zhao Dongyan , Liu Liang , Tian Rui
Published: February 2021

Due to the demand in the field of industrial control, we developed a CPU core based on ARMv8m architecture [1], named TS400, and its performance is comparable to Arm Cortex-M33 [2]. The TS400 has four stages of pipelining, thus having a higher clock frequency than Cortex-M33 which has three stages. With the increase of pipeline stages, extra idle clock beats will be introduced when the pipeline is flushed, which will increase the clock cycles per instruction (CPI) value and decrease the score of CoreMark. Accurate instruction fetch and branch prediction can effectively reduce the impact of refreshing pipeline, at the cost of extra logic resources. In TS400, an aggressive branch instruction prefetch method is designed. Compared with branch prediction technology, this method does not need complex branch prediction logic and is suitable for the design of embedded CPU. The aggressive branch instruction prefetch method includes: 1) reducing the time cost of conditional branch target fetching to the minimum by taking the branch first and then confirming the branch taking result; 2) optimizing the bus control signal timing of the prefetch instruction to make the target address prefetch respond in time. The aggressive branch prefetch method reduces the impact of pipeline stall caused by the execution of conditional branch instructions as much as possible, thus achieving better running performance than Cortex-M33 at the same clock frequency, while the clock frequency performance is superior to Cortex-M33.
Technology and test of fiber Bragg grating in composite materials
Authors: Mei-ling Shi , Chen Yang , Yun-long Hu , Hong Yao , Chao-jun Xin
Published: February 2021

In this process, the processing flow of fiber Bragg grating (FBG) embedded carbon fiber reinforced composites are prepared by means of pressurized film forming and end-surface elicitation. Firstly, the development of composites in aerospace field is introduced. Then, according to the principle of FBG sensor, a scheme for embedding fiber grating into carbon fiber composites is designed. There are three key steps involved in this process, namely, laying the bare fiber parallel to the carbon fiber cleavage direction, applying the end-surface elicitation method with the use of stainless steel thin tubes and Teflon fine tubes for protection, and pasting the rubber strip tile on the end to prevent the curing of the fiber break. After processing, a 260x60x3mm surface intact product is made according to the design scheme. There is no deformation in Carbon fiber surface and the end-surface is intact. Experimental tests show that this product has good temperature and strain response.
Research on Creep Constitutive and Numerical Simulation of Composite Solid Propellant
Authors: Feng S.X. , Qiang H.F. , Liu Y.X. , Wang X.R. , Geng T.J. , Yang Z.W.
Published: February 2021

Through the composite creep solid propellant creep experiment, the composite solid propellant curve is obtained. The power rate constitutive model, linear viscoelastic model and Schapery nonlinear constitutive model are used to describe the creep process. The study shows that Schapery modified nonlinear constitutive model can better describe the creep properties of composite solid propellants. Through the ABAQUS user subroutine, the finite element application of Schapery’s creep-type nonlinear constitutive model is studied. The research results in this paper can provide a reference for the analysis of the creep effect of the grain during the vertical storage of the solid rocket motor.
Thermal performance affected by the mesoscopic characteristics of the ceramic matrix composite for hypersonic vehicle
Authors: Lei LIU , Xiaofeng YANG , Guangming XIAO , Dong WEI , Yanxia DU
Published: February 2021

The rigorous thermal environment brought by long-time high-speed flight is imposed severe requirements on the structural bearing capacity and structural thermal safety of the aircraft. The integrated non-ablative thermal protection system based on continuous fiber-reinforced ceramic matrix composites is becoming a hot spot on the design of aircraft structures. However, the multi-scale, non-linear, non-uniform features of such materials, as well as complex thermal and mechanical characteristics, pose serious challenges to structural design and evaluation. Under the aero heating environment, the non-uniform temperature rising and thermal matching between different components in the continuous fiber-reinforced ceramic matrix composites are extremely complicated, which has a significant influence on the thermal safety performance of the structure. In this paper, based on the commonly used 3D orthogonal weaving process and the thermal characteristics prediction method of fiber bundles considering the effect of PyC interface layer, the fluid-structural strong thermal coupling characteristics of different woven parameters in typical aircraft structure is carried out. Quantitatively characterizing the heat transfer characteristics of this new material under the actual flight condition of the aircraft can further to improve the accuracy of the thermal property parameters obtained based on the ground test. The analysis results show that increasing the proportion of fiber bundles in a certain direction is the most effective method to increase the thermal conductivity in this direction. At the same time, the arrangement of the coupling yarns will also have a greatly influence on the thermal conductivity of the material. These results is of great significance for the design of the materials.
Study on the optical emission spectrum diagnosing of the low-temperature plasma using a collisional-radiative model based on the detailed-term-accounting approximation
Authors: Qiao Kuan , Sun Qing-Lin , Yang Xiong , Cheng Mou-Sen , Guo DaWei , Yang Chu
Published: February 2021

Considering the difficulty of large computation and the characteristic of helicon plasma, a modified collisional-radiative model was proposed for the diagnosis of low-temperature helicon argon plasma. A simplified 47-level is proposed due to the lack of experimental support of transition data at high levels as well as heavy computation to obtain macroscopic parameters of helicon argon plasma, e.g., electron number density ne and electron temperature Te. A creative twice-matching method is proposed in the model because the current double-line intensity ratio method shows significant sensitivity in diagnosing low-temperature electrons. Calculations based on this model shows the spectrum intensity depends on the electron temperature as well as density for low-temperature plasma, especially when it’s below 6eV. The twice matching process based on the priori knowledge chooses 15 spectrums cognizable within the wavelength from 680nm to 860nm, adopting the absolute values of the lines to match with the results calculated by the collisional-radiative model. This method greatly reduces the average error to 13.7%. The result indicates that the precision of the electron temperature and density has been improved a lot and the relative errors are 25% and 40%, respectively. Within the accuracy range above, the research shows when RF power is 500-800W and the pressure is 0.5-1.3Pa, the electron number density rises with the increasing RF power and decreases with the increasing magnetic field strength (450-900G) and gas pressure. Moreover, comparing to the number density of electrons, the electron temperature changes less and rises with the decreasing pressure.
An estimation method for parachute parameters
Authors: Li Zhibin , Cai Wenquan , Wu Yunchen
Published: February 2021

As a significant tool of transportation widely used in the logistics field, a well-performed parachute is highly required for this demand, especially for the sake of higher cost performance. The current study aims to investigate the internal relationship amidst various parameters of the parachute, conducting error analysis and accordingly providing an optimal experimental scheme. The objective of this experiment is to determine reference area and the resistance coincident, which are primarily parameters to estimate the weight of the designed parachute. Because the reference area is hard to determine using regular geometry method, a new parameter area ratio is redefined as the ratio of the original area of parachute surface to the reference area so that the reference area can be calculated by solving geometry problem. A simplified assumption that the parachute can be seen as a quasi-rigid body was previously made in order to approach the ideal parachute. Despite several limitations of the experiment, the final results perfectly aligned with the pre-experiment expectation. By following the similar procedures and after several trials, the ratio of the original area of parachute surface to the reference area was determined to be 3.90 and the resistance coincident to fall in the range of 2.00-3.00.
Research and establishment of steam dryness detection method
Authors: Wu Yusheng , Zhang Chunyuan , Qian Jichun , Wu Junhui
Published: February 2021

In this paper, by designing the overall idea of the pipeline steam dryness control measurement system, designing and implementing the pipeline steam dryness control measurement system, constructing the pipeline steam dryness control measurement test platform, integrating the pipe steam dryness control measurement system and the effect verification, studying and establishing the steam dryness detection method to improve the application effect of steam in the tobacco processing process.
Prediction of engine total pressure distortion in improved cascaded forward network
Authors: Fenglei Shi , Kuan Wang
Published: February 2021

In order to solve the problem of the result delay in the real-time calculation of engine inlet total pressure distortion index in flight test, the multi-step prediction of engine inlet total pressure distortion index in flight test is carried out. The average prediction error of traditional cascade forward neural network prediction model is higher than traditional autoregressive integrated moving average model. An improved algorithm is proposed. By establishing a time series dynamic level model, the time series of engine inlet total pressure distortion index is divided into low dynamic series and high dynamic series by using particle swarm optimization algorithm. The cascade forward neural network prediction model is used for training and prediction respectively. The results show that the average prediction error and maximum prediction error of the improved algorithm are reduced by 3.90%, 10.66% and 3.29% and 1.38% respectively compared with autoregressive integrated moving average model and traditional cascaded feedforward neural network.
Research on Longitudinal dynamic characteristics of flexible waverider based on CFD/CSD/RBD method
Authors: Shang Y M , Hua R H , Yuan X X , Tang Z G , Wang Z W
Published: February 2021

The shape of hypersonic aircrafts represented by the waveriders is becoming more slender and flatter, thereby greatly reducing the structural rigidity of the aircrafts. This innovation is applied to satisfy the demand of long-range flight. In this paper, the effect of elastic deformation on the trimming and dynamic stability of the waverider was analysed through Computational Fluid Dynamics(CFD)/Computational Structural Dynamics(CSD)/Rigid Body Dynamics(RBD) coupling. The results show that as the decline of structural stiffness, the angle of attack increases and the lift-drag ratio deteriorates when the waverider is trimmed. The elastic deformation makes the dynamic center get forward, and the static stability of waverider becomes poorer. What’s more, the dynamic stability of pitching motion is reduced due to the coupling of rigid-body motion and elastic vibration.
Design and Test Verification of Hybrid Airfoil Based on Multi-objective Genetic Algorithm
Authors: Li Zhao , Yang Guangjun , Tong Xiaoyan , Jiang Feng
Published: February 2021

Certification of modern aircraft requires the manufacturers to demonstrate flight safety within the flight envelope, including icing conditions. Icing wind tunnel test is an important way for flight safety and certification. However, the size of aircraft models that can be tested in icing wind tunnels is limited by the dimensions of the facilities. It is an effective method to replace the large model with a hybrid airfoil to carry out the experiment. If properly designed, these hybrid airfoil models can generate the full-scale ice accretion on the leading edge and reduce blockage. Based on the similarity of flow field in the leading edge, a multi-objective genetic optimization algorithm is proposed to design the hybrid airfoil under different conditions. The pressure tests are carried out and compared with the leading edge pressure coefficient of the corresponding full-scale airfoils. The design and experimental results show that the pressure coefficient deviation between the hybrid airfoils designed and the corresponding full-scale airfoil in the 15% chord length range of the leading edge is within 3%. Finally, icing wind tunnel test is used to inspect the ice shape of full-scale and hybrid airfoils, and the results shows that ice accretion process have good agreement of hybrid and full-scale airfoils.
Fracture failure analysis on swivel nut of 30CrMnSiA steel in aircraft
Authors: Chen Cheng , Chen Zhen , Li Shangqiang , Zhu Jinpeng , Li Tianxiang , Bian Haiqing
Published: February 2021

In this work, the cracks of HB4-49-14CdD swivel nut in aircraft were found and analyzed by macroscopic observation, morphology testing and metallographic examination. In order to figure out the cause of cracks, manufacturing and assembling process were investigated, and finite element method was used to simulate the tightening process. The results showed that overload tightening torque lead to the fracture and failure of swivel nut.
Modeling and Analysis of Customer Preference in Civil Aircraft Manufacturing Supervision
Authors: Feng Yu , Lei Hua
Published: February 2021

Customer manufacturing supervision of civil aircraft refers to the operator of the aircraft or its authorized entity’s supervision and inspection process during aircraft’s manufacturing and final assembly, through which the operator (airline company) ensures that the delivered aircrafts meet the requirements of approved technical standards, process specifications, and engineering documents, as well as confirming that optional components and aircraft’s layout comply with technical standards required by the purchase contract. Manufacturing supervision brings forward aircraft delivery inspection, qualitative improvement of which enables the improvement of efficiency in single aircraft airworthiness inspection, ensuring aircraft’s continued airworthiness. From the manufacture’s perspective, analyzing customer’s needs and preference on manufacture supervision in advance, taking advantage of the relatively long production cycle, disposing proper engineering solutions for manufacture deviations, reducing the business negotiation items due to deviations not only helps reach the goal of customer supervision, but also helps optimize engineering dispositions.
Wall temperature correlation for convective heating prediction of aircraft heat shield in high-enthalpy and chemically reacting flow
Authors: Yang Xiaofeng , Xiao Guangming , Liu Lei , Du Yanxia , Gui Yewei
Published: February 2021

Hypersonic aircrafts and aero-engine combustion chambers both generate non-equilibrium and high-enthalpy flows and bring complex material-relied heat convection performance. The convective heating prediction is difficult due to unknown surface thermal state, leading to poor usability of wall temperature correlation method (WTCM). This paper aims at improving WTCM for convective heating prediction in chemically reacting flows through coupling computation of catalysis on thermal protection materials. Modified WTCM for chemically reacting flows accounts for two distinct physical events driven by temperature gradient and species reaction, which follow the Fourier’s and Fick’s laws, respectively. Preliminary validation testing demonstrates the feasibility of the modified WTCM to rapidly evaluate aerodynamic heating with limited deviation. The current research provides essential technical support for the evaluation and design of hypersonic aircrafts and aero-engine combustion chambers.
Analysis of thermal lubrication characteristics of aero-gear pump journal bearing
Authors: Ning Gao , Li Huacong , Xianwei Liu , Zhu Jiaxing , Wei Shijie
Published: February 2021

In order to study the thermal lubrication characteristics of aero-gear pump journal bearing (APJB) under certain load and low medium viscosity, a APJB numerical model was established based on the combination of Reynolds and adiabatic flow energy equations. The hydrodynamic lubrication and temperature effects on the viscosity are considered and the finite difference method is adopted. The results show that with the increase of APJB width parameters, the eccentricity decreases monotonically, the minimum oil film thickness increases, the friction resistance increases and the end discharge decreases. In addition, the eccentricity of bearing, maximum oil film pressure, end discharge flow and oil film thickness increase with the APJB radial clearance, while the friction and temperature inside the APJB decrease. When the APJB width changes from 21 to 27mm, the maximum oil film temperature and pressure increases by 2.16% and –35.23%, respectively; when the radial clearance changes from 0.0315 to 0.0413mm, the maximum oil film temperature and thickness decrease by 3.03% and 8.99%, respectively.