bluuebunny/crossref_metadata_2025 huggingface dataset:
The Integration of Polarization Splitter-Rotator and Photodetector in Optical Receiver
Authors: She Xiaojuan , Liao Han , Zhao Yingxuan , Zhu Junbo , Li Yang , Tao Lue , Zhu Zijian , Huang Rui , Liu Xiang , Qiu Chao , Huang Haiyang , Sheng Zhen , Gan Fuwan
Published: April 2021

Because of high-index contrast Si/SiO2 system, polarization sensitivity is a severe problem in photonic integration devices. In this paper, we design a integration devices comprised of polarization splitter-rotator (PSR) and germanium photo detectors (PDs) on chip. The integration of PSR and PD can realize the integrated layout which can realize the measurement of PSR polarization properties. After calculation, the on-chip loss of the polarization beam splitter is 1.19dB, and the polarization isolation of the system is 14.59dB/5.141dB in TE0/TM0 mode.
Research Analysis of PCB Design’s Influence on DDR4 Highspeed Signal Integrity
Authors: Li Fang
Published: April 2021

With the increase of the signal transmission rate of electronic devices and the increase of the PCB wiring density, PCB design has a growing influence on signal integrity. To reduce the number of the problems concerning signal integrity at the initial stage of electronic product design and increase the success rate of the designing of electronic products, some interference signals of PCB are canceled to improve the accuracy of signal integrity test, with the high-speed parallel bus of DDR4 as an example. Analysis is done through measurement of various simulation tools to change the PCB design parameters of DDR4 data transmission line, hence the optimum wiring method will influence the signal quality. Meanwhile, RC parallel impedance matching optimization is carried out to deal with the impedance mismatch at the network load end. In this way, the problem concerning DDR4 high-speed signal integrity is effectively solved.
A dynamic power control scheme based on node priority in V2X
Authors: Li Huiwen , Zhang Xin
Published: April 2021

V2X (Vehicle-to-everything) is aimed to provide efficient data sharing among communication nodes in traffics. In order to guarantee the quality of communication, V2X need to support node priority as one of QoS (Quality of Service) mechanisms, which is related to nodes’ different requirement of message dissemination. Therefore, a dynamic power control scheme based on node priority for V2X is proposed. By assigning distinct power adjustment range for each level of node priority and incorporate distribution of neighbouring nodes’ priority into power setting, it’s able to achieve flexible power control and differentiated communication performance. The performance of proposed scheme is testified through network simulation.
Research on vehicle cruise control based on online asynchronous supervised reinforcement learning
Authors: Han Zhonghai , Yang Liangyi , Zhang Qiang , Fan Jie
Published: April 2021

This paper proposes a vehicle cruise control strategy based on asynchronous supervised reinforcement learning, which improves the driver’s reception in the process of vehicle deceleration and following. The control strategy takes actor-critic network as the basic control unit, which guides the control strategy to achieve driver-likely cruise effect by adding real driver cruising data into the supervision network. Simultaneously, combined with the driver online feedback mechanism for real-time training, it realizes offline training and online updating of network parameters. The simulation results show that the asynchronous supervised reinforcement learning algorithm can quickly update the parameters of the control network, and constantly update the control strategy by online learning combined with the actual driving data to better simulate the driver’s driving characteristics.
Depth Guided Cross-modal Residual Adaptive Network for RGB-D Salient Object Detection
Authors: Zhao Zhengyun , Yang Qingpeng , Yang Shangqin , Wang Jun
Published: April 2021

Depth modal features can provide complementary information for salient object detection (SOD). Most of the existing RGB-D SOD methods focus on fully combining RGB and Depth modal features without distinguishing them. In this paper, we propose a new depth guided cross-modal residual adaptive network for RGB-D SOD. We use two independent resnet-50 to extract the features of the two modes respectively. Then the cross-modal channel-wise refinement module is designed to obtain complementary modal information. We design a crossmodal guided module to make complementary modal information guide RGB image feature extraction. Finally, the residual adaptive selection module is used to enhance the spatial mutual concerns between the two modal features to achieve multimodal information fusion. Experimental results show that our method can achieve a more reasonable fusion state of RGB and Depth, and verify the effectiveness of our final saliency model.
Calculation of the degree of polarization based on the correlation between reflection and transmission
Authors: Zhang Jinghua , Zhang Yan , Shi Zhiguang , Yu Zhang , Feng Ling , Di Liu , Xiaoran Shi , Yuchang Suo
Published: April 2021

Polarization is a basic property of light. In nature, polarization is mainly caused by the refraction and reflection on the surface of objects. The polarization of light can be measured quantitatively by the degree of polarization. By calculating the degree of polarization of an object’s surface, we can obtain the effective information for target detection, recognition, material judgment, and so on. The reflection and refraction effects occur simultaneously on the surface of transparent objects, so the measurement of the degree of reflection and transmission polarization is a challenge problem. In this paper, a method based on normalized crosscorrelation is proposed to extract the zero point pixels, and the degree of reflection and transmission polarization can be effectively calculated by using the zero point pixels.
Quotation Strategies of Non-Truck Operating Common Carrier Based on Multivariate Statistical Regression and Triple Pricing Model
Authors: Zhao Sifan , Fan Lidan , Yu Penglin
Published: April 2021

Combined with the existing transaction orders of carless carriers, the numerical information and text and information are extracted, and the related factors of line guide price are integrated, and the relationship between relevant factors and line guide price is studied. Using the unified unit and 0-1 text setting method, preprocessing data, eliminating the influence of numerical units, quantifying textual data, so that the data can be put into the relevant equations for testing. According to the characterization relationship between the guiding price and factors, a multivariate linear statistical regression model was established, and the statistical P value was used for testing to verify the availability of the model. The index of price overflow rate and equilibrium degree are put forward as the standard to evaluate whether the transaction price of an order is reasonable. The normal distribution of orders can be verified by looking at the scatter plot of the cumulative percentage of transactions and the price spillover rate of orders. According to the central limit theorem of large sample data with normal distribution, the sample can be sampled in sections and the summation can be taken as the transaction probability. According to the operation mode of the vehicle-free carrier platform, the transaction mode of three quotations is added to re-quote the line. The pricing obtained from multiple linear statistical regression is used as the benchmark, and the dynamic pricing strategy is re-customized according to the principle of the first quotation giving priority to lowering the price, the second quotation giving priority to stabilizing the transaction, and the third quotation giving priority to the success rate. The sensitivity analysis shows that the platform can get a revenue increase of 33%∼48% based on this new pricing strategy, and meanwhile improve the balance and stability of orders. The research report provides a calculation method of a new quotation model with high turnover rate and stable income for the non-truck operating common carrier platform, and has a guiding significance for the construction of the non-truck operating common carrier trading system, especially the rationality of the price formulation and the stability of the transaction order quantity.
Task offloading algorithm of vehicle edge computing environment based on Dueling-DQN
Authors: Ouyang Yi
Published: April 2021

With the wide application of the Internet of vehicles, the rapid development of intelligent vehicles provides drivers and passengers with a good driving and riding experience. However, how to process a large amount of data messages in real time on resource-limited vehicle terminals is still a huge challenge, and it will cause great energy consumption to terminal devices. In this paper, a semi-online task distribution and offloading algorithm based on Dueling-DQN is proposed for time-varying complex vehicle environments. Firstly, the vehicle offloading system is built by the reinforcement learning, because the original optimization problem is a joint optimization problem with high complexity, and divided into the vehicle scheduling sub-problem and the vehicle computation resources optimization subproblem. We predicts different vehicle offloading behaviour, and calculates total rewards value after a series of vehicle offloading action, so as to update the vehicle offloading decisions. The simulation results show that this algorithm can improve the efficiency and energy consumption of computation tasks to a certain extent.
A Ship Target Detection and Tracking Algorithm Based on Graph Matching
Authors: Li Gaoyue , Qiao Yulong
Published: April 2021

This paper proposes a target detection and tracking system based on Hungarian graph matching algorithm and Kalman filter. Specifically, the algorithm converts continuous frame images of a detection network such as YOLOv3 into graph structure data as input information, and expresses the position information between the target and the target as points and lines in the figure. Then the Kalman filter is used to predict the position of the target in the next frame, and then the largest match between the picture constructed by the current frame and the picture constructed by the next frame is determined by the metric method of the fusion of the apparent feature and the motion feature, to achieve the purpose of tracking the target. For ships doing nonlinear motion, this paper proposes to improve the traditional Kalman filter system to an unscented Kalman filter system based on UT transformation. Experimental data shows that this method effectively improves the tracking effect of ships doing nonlinear motion.
Research on Database Parameters Tuning Method Based on Embedded Device
Authors: Geng Xiaoli , Xu Wenchao , Yin Yonghong
Published: April 2021

Various kinds of embedded terminal devices have enriched our lives. As a consequence, a huge amount of data has been generated, which often results in slow operation of the devices and a dramatic drop in data processing capacity. Database parameter tuning will be an important way to maintain or improve the performance of the devices. As database performance is affected by multiple parameters, manual adjustment is more and more difficult. With the development of machine learning, database automatic parameter tuning technology has become one of the main choices to solve this problem. This paper proposes to use MARS regression algorithm to optimize the database parameters of embedded devices, to perform regression prediction and fitting on each part of the data space respectively, and obtain the optimal parameter through the processes of forward, backward, and model selection. Experiments show that compared with the traditional method, the parameter optimization results generated through the method proposed in this article are very nearly the same as those obtained through the traditional method, but the time efficiency is significantly improved, hence improving the efficiency of embedded project development.
GCNGAN: Translating Natural Language to Programming Language based on GAN
Authors: Dai Hongming , Chen Chen , Li Yunjing , Yuan Yanghao
Published: April 2021

Cross-language translating has been well solved with the help of the processing of natural language processing(NLP). However, there are a few studies done about the domain of translating the natural language to programming snippets. Traditional method are mostly rule-based and limited to specific areas. In this paper, we propose a model based on Graph Convolutional Network(GCN)-Generative Adversarial Networks(GAN) to translate natural language to programming language. The generator is the encoder-decoder framework in which the encoder and the decoder are all bidirectional RNNs and GCN. And discriminator in GAN is also bidirectional RNNs and GCN. To improve the performance of semantic parsing, we also apply the attention mechanism to it. The experimental results indicate that our model has achieved comparable performance with some other state-of-the-art methods and has the stronger generalization ability.
A novel scatterer model for the security of key generation based on DISC model
Authors: Yang Yuanhang , Zeng Xin , Xue Xiaoping
Published: April 2021

Physical layer security is a method of extracting encryption keys according to the randomness of reciprocal propagation channels between legitimate users, and the security under normal circumstances is ensured according to the decorrelation between these channels and those tapped by eavesdropper. However, evidences show that in some scenarios, such as the environment of quasi-static or insufficient scattering, the tapped channel still has a strong correlation with the legitimate channel, leading to bits leakage and security imperilment of key generation. The effect of introducing scatterers has been experimentally proved, however, these studies are based on fixed positions or special models and there is yet a lack of research on the influences brought by various scatterer distributions. In this paper, we introduce scatterers into single-bounced DISC model and control their distributions through a probability density function with two degrees of freedom, aiming to deeply investigate the impacts of scatterer distribution on channel decorrelation as well as key security. Simulation results prove that spiral correlation between tapped channel and legitimate channel can be effectively reduced by increasing scatterers and arranging them around the legitimate receiver, which make contributions to reduce key leakage and improve security.
Emotion Recognition Model Based on Multimodal Decision Fusion
Authors: Zheng Chunjun , Wang Chunli , Jia Ning
Published: April 2021

In the process of human social activities and daily communication, speech, text and facial expressions are considered as the main channels to convey human emotions. In this paper, a fusion method of multi-modal emotion recognition based on speech, text and motion is proposed. In the speech emotion recognition (SER), a depth wavefield extrapolation - improved wave physics model (DWE-WPM) is designed. In order to simulate the information mining process of LSTM, a user-defined feature extraction scheme is used to reconstruct the wave and inject it into DWE-WPM. In the text emotion recognition (TER), the transformer model with multi attention mechanism is used to recognize the text emotion combined. In the motion emotion recognition (MER), the sequential features of facial expression and hand action are extracted in groups. Combined with the bidirectional three-layer LSTM model with attention mechanism, a joint model of four channels is designed. Experimental results show that the proposed method has high recognition accuracy in multi-modal, and the accuracy is improved by 9% in the interactive emotional dynamic motion capture (IEMOCAP) corpus.
Key Indicators Analysis Approach for Green Power Considering Contributed Characteristics
Authors: Zhang Xiangcheng , Chen Laijun , Li Hongxia , Si Yang , Yang Fan , Jiang Libo , Guo Yongqing
Published: April 2021

Key green power indicators are information which can intuitively reflect the status of green power construction in a region. Selecting reasonable key indicators will help to identify week link the development of green power, and promote the development of clean energy and power systems. A multi-dimensional quantitative analysis method for key green power indicators is proposed in this paper. First of all, this paper designed a set of indicators starting from the different links of power supply, grid and load. The indicator set includes three dimensions: green power development, green energy sharing and green power living, and the selecting method key green power indicators is established. Then, from the aspects of indicator score and indicator weight, a model for quantitatively evaluating the development level of green power was constructed to analyze the development week link of green power. Finally, the effectiveness and feasibility of the proposed method are verified by using the indicator data of Qinghai Province. Qinghai’s green power development level and development trend are quantified. The development balance of different links of green power was analyzed, and the constructed indicators are used to obtain the weak links of Qinghai’s green power development. The calculation examples show that the evaluation and analysis method proposed in this paper can help to quantify the level of green power development and guide the coordinated development of various construction parts.
Jet Mill Bit for Enhancing Cuttings Transportation and Decreasing Bottom-hole Pressure: What are the Characteristics of Internal Flow Field?
Authors: Xu Jie , Zou Yiqi , Chen Xuyue , Hong Yuqun , Yang Jin , Xie Tao , Sun Lianpo
Published: April 2021

Jet Mill Bit (JMB) is used to reduce the cuttings bed in horizontal drilling. In this paper, the internal flow field is simulated by computational fluid dynamics (CFD) modelling to analysing the pressure field, velocity field and turbulent energy field. At the same time, the DPM model is also used to simulate the particle field. The results show that the cuttings have good acceleration and pulverization performance in the accelerating tube. The drilling fluid generates high-speed injection when passing through the reverse nozzle outlet resulting in negative pressure in the acceleration tube, which generates suction force at the bottom of the well and accelerates the return of the cuttings and the maximum pressure drop is close to 0.5Mpa. The work done in this paper is instructive for the optimization design of Jet Mill Bit and it is expected to promote its field application.
Research on Economic Evaluation Model and Application of Deep Reservoir Based on Break-even Method
Authors: Peng Mengyun , Chen Cheng , Qin Jichao , Zhang Hui
Published: April 2021

In order to strengthen the economic level of deep reservoir development, this article takes the oil reservoirs in the Zhungeer Basin, Xinjiang as an example, and uses the break-even method to evaluate and analyze the economic benefits of regional reservoir development. Based on the characteristics of the economic structure of reservoir development, a deep reservoir economic evaluation model was constructed and applied to the evaluation of the economic benefits of the reservoirs in the northwestern margin, the southern margin, and the eastern Zhunge. The application results show that the overall economic benefits of the northwestern margin are the highest, and the economic benefits of category A in the south margin are the highest. In order to further improve the economic development level of deep reservoirs, it is recommended to focus on the geology of reservoir distribution in Class I economic reliability areas.
Community structure of nekton in the waters around Dongtou Island in Autumn of 2019
Authors: Zhang Dongrong , Xu Hengtao , Wang Zhifu , Fen Weihua , Zhang Haifeng
Published: April 2021

Resource distribution characteristics of nekton in estuarine waters are related to hydrology, ecological environment changes and anthropogenic factors. A total of 49 species of nekton was found from 10 sites in the estuarine waters around Dongtou Island (DTI), with which the species of fish were in the highest proportion, followed by shrimp and crab. Average nekton biomass and abundance were 522.61 kg/km2 and 28.60×103 ind./km2, significantly higher than that of previous studies. The distribution pattern was highest in the eastern part of DTI, lower in the ORE area, and lowest in the northern part of DTI. The intersection of water currents was an important hydrological factor in forming the high resource density area of nekton. Changes in the number of nekton were driven by the contribution of the two economically valuable dominant species of fish Harpodon nehereus and crab Portunus trituberculatus. The mean value of H’ of nekton abundance was higher than that of nekton biomass. The species diversity of nekton in the sea near DTI was relatively low and community structure was in a relatively unstable state. The impact of human development activities on the nekton resources cannot be ignored, further research is essential.
Research on the Application of Radar Echo Model Based on LSTM in Immediate Weather Forecast
Authors: Xu Wei
Published: April 2021

This research analyzed the issue of radar echo extrapolation based on the Long Short-Term Memory (LSTM), established the echo extrapolation algorithm on the basis of the LSTM model, and explored the practical application of this algorithm in the prediction of rainfall volume and in the comprehensive similarity of cloud images. The practiced extrapolation test showed that the average comprehensive similarity of the radar echo extrapolation algorithm based on the LSTM model in the extrapolation within 15 minutes and 20 minutes was 87% and 80% respectively, and the similarity exceeded 70% in the extrapolation test in a relatively longer term. In the rainfall prediction of the next 20 frames of images, this algorithm got an instant hit rate of 64.1%, a false rate of 20.6%, and a key success index of 43.8%. Compared with the traditional radar echo extrapolation algorithm, this echo extrapolation algorithm based on the LSTM model had an excellent application effect in the aspect of weather forecast. The contents of this research can provide scientific and effective reference materials for the subsequent application researches of the technology in weather forecast.
Evaluation of Coral Reefs’ Restoration in the South China Sea
Authors: Shan Zixuan
Published: April 2021

As one of the toughest environmental problems Earth is facing, climate change brings many negative impacts, such as rising sea levels, increasing number of natural disasters, adverse changes in the marine environment, and biodiversity loss. The rising sea-level and marine environment changes pose a massive threat to islands and coral reefs in the South China Sea. This paper reviews the evaluation of coral reefs’ restoration in the South China Sea. The result shows that these methods are practical, and they will benefit the restoration and expansion of coral reefs globally.
Application of high density resistivity method in landslide detection
Authors: Di Qi , Jian-Jun Niu
Published: April 2021

Landslide geological hazards often occur and are relatively harmful, which seriously threaten the safety of people’s lives and property. Therefore, accurate detection of slope stability is of great interest. Based on the full understanding of the geological conditions of the test area, this paper uses the physical property of the difference in the resistivity of the rock and soil of the landslide mass, and uses the high-density resistivity exploration method to detect the potential sliding surface of the slope in the test area, and finally through inversion. The resistivity profile is calculated, the spatial distribution characteristics of different rock and soil layers in the test site are determined, and the geological interpretation map is formed according to the analysis results, which delineates the potential landslide surface of the slope, and provides an accurate basis for future landslide disaster prevention and control projects.
3D laser scanning and surveying adjustment in traffic infrastructure management
Authors: Guo Runhua , Shi Pengcheng , Liu Siquan , Geng Jingjie
Published: April 2021

In view of difficulties in automatic and refined management of traffic infrastructure, road lamps and signboard in the test road section are taken as examples, an application framework for automatic and refined management of traffic infrastructure is proposed by using 3D laser scanning technology combined with GPS (Global Positioning System) and QGIS (Quantum Geographic Information System). The advantages of 3D lidar sensor, such as high precision, strong anti-interference ability and good real-time performance are fully used. Through data fitting by using total least squares method, digital management of infrastructure is carried out and its precision is high. Combined with GPS and QGIS, the spatial information of infrastructure is developed. In this way, manpower and efficiency of management of infrastructure are saved and improved.
Dilution Diffusion Model Research of Offshore Deep-sea Discharge in Coastal Area
Authors: LiYa Xia , XuBin Wen , YongLiang Dong
Published: April 2021

The sewage diffusion effect under deep water was carried out between different diffuser design parameters based on the hydraulic model test. According to the test of diffuser length, riser spacing, riser number, riser nozzle number, horizontal azimuth angle and jet angle, the specific parameters of diffuser need to be determined comprehensively considering the water surface sewage field, sewage diffusion degree, project cost, etc. We used a coastal marine disposal project in China as an example. The article analyzes the influence of diffuser technology on the dilution and diffusion of sewage under the condition of large water depth, and puts forward the engineering design schemes of different horizontal azimuth angle, different jet angle and different diffuser length.
Thoughts on innovation and development of Geomechanics
Authors: Li Huijun , Song Licai , Zhang Linyan
Published: April 2021

Geomechanics is a discipline invented based on geological backgrounds of China, and has made great contributions to national key demands in both theoretical and practical aspects. However, both theoretical and practical challenges are facing this discipline. In this article, the authors analysed the developing history of Geomechanics, new demands raised by current social and theoretical development, its advantages, and pointed out business layout for developing Geomechanics in fulfilling national demands.
An extraction method of cultivated land in karst area based on Landsat time series
Authors: Wang Limeng , Wang Jiasheng
Published: April 2021

It is of great significance to grasp the distribution of cultivated land in karst area for protecting cultivated land and maintaining regional food security. Based on Landsat 8 OLI remote sensing images, this paper took Fuyuan County of Yunnan Province as an example, used a classification method combining multi-feature construction with random forest to extract the distribution of cultivated land in Fuyuan County in 2019. The experimental results showed that the overall accuracy was 0.93, and the Kappa coefficient was 0.90. This method could reduce the interference of mixed pixels to a certain extent and had a better classification effect. The cultivated land area in Fuyuan County was 1200.42 km2. The cultivated land was distributed in all townships of the whole county, and it was mainly concentrated in the northwest, central and part of the southern regions of Fuyuan County, such as Housuo Town, Zhong’an Town, Dahe Town, Yingshang Town, Zhuyuan Town, and Shibalianshan Town.
Prediction of Riverbed Evolution under Different Operation Modes of Three Gorges Reservoir at A Reach with Beaches in Flood Seasons
Authors: Ge Hua , Wang Min , Deng Chunyan
Published: April 2021

Different reservoir operation modes in flood seasons will have a profound impact on the evolution of the downstream reach of the dam. In this paper, a sandy reach with beaches in the downstream of the dam is selected. Based on the water and sediment conditions output from the Three Gorges Reservoir under different operation modes in flood seasons, the erosion and deposition trend in the reach is predicted and calculated. The results show that the total inflow of the reach is basically the same during the operation period, but with the decrease of the controlled discharge, the action time of the bank full discharge increases, and the total scouring amount of the reach slightly increases, which is conducive to the development of the channel.
Early Cretaceous magmatism of the Southern Qiangtang terrane and its tectonic significance
Authors: He Haiyang , Wang Tingting , Zhang Yuqian
Published: April 2021

The tectonic evolution of the Bangong-Nujiang Tethys is known as the most important event in the late Mesozoic in the central Qianghai-Tibet Plateau. Magmatism is a probe and window for detecting deep crust, which also records the process of tectonic evolution. The magmatic arc formed at Early Cretaceous in the Southern Qiangtang subterrane, was products of the Mesozoic magmatism during the long-term subduction of the Bangong-Nujiang Tethys oceanic lithosphere and the subsequent Qiangtang-Lhasa terrane collision. This article summarizes zircon U-Pb geochronology, major and trace elements, and Sr-Nd-Pb-Hf isotopic data for the Early Cretaceous magmatic rocks located in the southern Qiangtang subterrane of central Tibet. However, there are three hypotheses about the tectonic background of the Early Cretaceous magmatism of the South Qiangtang subterrane: (1) oceanic ridge subduction; (2) slab roll-back; (3) slab break-off.
Image of seismological anomaly before the February 18, 2020 Changqing M4.1 magnitude earthquake
Authors: Zhao Jinhua , Cui Huawei , Li Cuiqin , Gai Dianguang
Published: April 2021

An earthquake of magnitude M4.1 occurred in Changqing County, Shandong Province (36.46°N, 116.65°E) on February 18, 2020. In this paper, we found from the image analysis of seismic activity and wave velocity ratio calculation before this earthquake that the magnitude M4.1 (No special markings on the magnitude of the earthquake: M for magnitude 5 (including magnitude 5) and above, M
L for below magnitude 5) in the 1-year scale before the Changqing M4.1 earthquake, inland Shandong and In the Bohai Sea, there is an orderly distribution of magnitude 2 earthquakes, multiple small earthquake sequences, a concentration with active of magnitude 3 earthquakes, the Changdao “earthquake window” “open” several times, and an abnormally low value of wave velocity ratio etc. Phenomena.
Discrimination of AVO Types in Shallow Reservoirs Based on Random Forest Algorithm
Authors: Liu Haonan , Wen Xiaotao , He Jian , Chen Qianshu , Zhang Xiaoqi
Published: April 2021

As we all know, AVO technology can be used to identify gas-bearing reservoirs and is of great significance to oil and gas exploration. The manual identification of AVO types of reservoirs has large human interference factors, low identification accuracy and long time-consuming. Therefore, this paper introduces the random forest algorithm, uses bootstrap repeated sampling and branch and leaf node splitting techniques to generate a large number of decision tree classifiers, and realizes the identification of the AVO type of the reservoir by counting the classification results of all decision trees. Firstly, a velocity density model is established based on logging data in the working area. Secondly, use the Shuey approximation formula to calculate the AVO curve and obtain the fitted polynomial corresponding to the curve. Thirdly, the morphological feature parameters are extracted according to the fitting polynomial as the input parameters of the training data set of the random forest algorithm, and the artificial AVO type recognition results are used as the output parameters to train and obtain a decision tree classifier. Finally, using the characteristic parameters of the AVO curve of the actual pre-stack seismic data as input parameters, the classification of the AVO type of the reservoir in the working area is obtained through the classification of the random forest decision tree. By comparing the results with the approximate support vector machine algorithm, it can be seen that the two algorithms approximate the AVO type discrimination results of the reservoir, and both have high accuracy, but the random forest algorithm requires fewer feature attributes, shows stronger generalization and has better universality.
Timber transportation using two types of trucks in industrial plantation forests, North Sumatra, Indonesia
Authors: Muhdi  , Lestari Bianti Dwi , Hanafiah Diana Sofia , Sahar Asmarlaili , Zaitunah Anita
Published: April 2021

The timber transportation is expensive, because wood besides having a light weight, is also deep implementation is often constrained by limited access, steep slopes and distances far away. The purpose of this study was to determine the productivity of timber transportation in industrial plantation forests of PT. Toba Pulp Lestari, North Sumatra, Indonesia. This research was conducted in the area of PT. Toba Pulp Lestari, North Sumatra, Indonesia. The research was carried out by taking a sample of twenty trucks with two different types of trucks by purposive sampling. The results showed that the shortest working time in activities transportation is the activity of unloading. The average volume capacity of truck was 10 m3 and 32 m3, respectively. The results of this study indicate that the average productivity produced by both types of trucks was 0.57 m3/hour and 1.46 m3/hour, respectively.
Earned value concept analysis on project monitoring (Case study: Faculty of Forestry Universitas Sumatera Utara building construction phase 1)
Authors: Syahrizal  , Jaya Indra , Putri Indarti Tamara
Published: April 2021

Construction projects have a high level of project complexity. Sometimes there are some late progress or cost overruns on project construction. Monitoring is the first step to control the project so that it can be seen as a large deviation in costs and schedules that occur. Therefore, to improve the effectiveness of monitoring, the earned value concept method can be used. The research began with data collection from the research location. After obtaining supportive data, it is continued with ACWP, BCWP, and BCWS data analysis. It is closing with the final results of all analyzes conducted. From the study of the concept of the value of the works reviewed until the 20th week, the BCWS value was IDR 14,816,705,720, the BCWP value was IDR 4,614,975,520, and the ACWP value was IDR 4,153,562,199. The CPI value is 1.111, while the SPI is 0.311, which means that the project is experiencing delays in terms of schedule but incurs actual costs that are less than the work already done. The final estimated project cost (EAC) is IDR 20,301,199,616, while the ECD value is 52 weeks for the project completion time.
Mixed-use building concept with energy conservation approach
Authors: Lubis Mohammad Dolok , Fachrudin H T , Claudya Bellinda , Ardiansyah Irwan
Published: April 2021

Humans have a variety of necessities of life contained in space and buildings. The mixed-use building design is an effort to unite several functions together in one building. The mixed-use building design considers the needs of the area to be designed, the surrounding environment, and the building user. The application of the concept of energy conservation in mixed-use building design aims to meet human needs and provide comfort for its users. The method used is mixed methods with observation and comparative studies with buildings that apply the concept of energy conservation. The mixed-use building concept will utilize solar panels as a passive design in the recreation zone, which can be a source of electricity in the recreation area at night. The mixed-use building models that are designed can be used to meet the principles of energy conservation that can be used in urban areas.
Unit cost analysis for road construction sustainability: A case study of national road in West Java Province, Indonesia
Authors: Anas Ridwan , Suyono Rudi S , Surbakti Medis S , Puji Hastuty Ika
Published: April 2021

Cost estimation of road construction is required at the early stages of a project used to describe the process of predicting a project’s cost before construction through the tender process. Unit cost for road construction has a different characteristic for each area, this is caused by the component that forms unit cost is different in each area, starting from the material, equipment to human resources. The unit cost of road construction is affected by several factors, such as project location, whereas the distance to the project location can affect the transportation cost of equipment and material, other than that there is an external cost for each road project. This study describes the variants of unit cost between the estimated cost and actual (contractual) cost, based on collected data for 62 awarded road construction projects during the last 3 years especially for major items of work in West Java Province. The result describes that cost under-estimates are more implemented than cost over-estimates in national road construction projects. The variances of unit cost can be used by the government as a reference for estimating the cost item because the high accuracy of unit cost is crucial for completing the road projects.
The utilization of plastic waste in a mixed pair of concrete brick walls
Authors: Nursyamsi N , Indrawan I , Surbakti MS , Glory O
Published: April 2021

Plastic is a daily consumable material due to its easy accessibility and affordability. The high production of plastic waste contributes to the increase risk of hazardous environment which is difficult to be processed and decomposed. One of the solutions is to recycle plastic waste. In this study, the types of High Density of Polyethylene (HDPE) and Polypropylene (PP) were utilized as substation material with 10% of ratio to be mixed in pair with concrete brick walls. The sample study was concrete bricks characterized with dimensions of 40x20x10 cm3 and 15x15x15 cm3. The addition of admixture SikaPayer HC-1ID and silica fume as additive was carried out to improve the performance of testing samples. Samples of concrete bricks were then attached on the wall as a mixed pair with dimension 105x95 cm2, and compression properties were performed. The results showed that visual appearances, content weight, and adsorption ability of two samples were classified as concrete brick type I, and the addition of HDPE and PP to the concrete bricks walls contributed into type II which were able to with-stand load around 2200 and 2800 Psi respectively. The other eminence that was observed from the addition of HDPE and PP was milder weight compared to neat concrete bricks.
Effect of using clamshell ash as stabilization material for clay
Authors: Hastuty Ika Puji , Rahman Aulia
Published: April 2021

Clamshells are the waste of clams which are usually consumed by people. Clamshells contain 66.70% of CaO, the chemical compounds that have pozzolanic properties, which can be used as a substitute for cement. The purpose of this study was to determine the effect of the addition of clamshell ash to the index value of soil properties, soil classification, soil plastic properties, free compressive strength value, and CBR value. The test was carried out with Unconfined Compression Test (UCT) and California Bearing Ratio (CBR). The result showed that according to AASHTO this soil was classified as A-7-6 (9) and according to USCS it was classified as CL (Clay - Low Plasticity). The original soil sample had a moisture content of 34.43%; specific weight of 2.65%; liquid limit of 47.33%; plastic limit of 17.45%; and plasticity index of 29.88%. The values of unsoaked design CBR and UCT for the original soil were 6.29% and 1,42 kg/cm2. Meanwhile, among all the variations, the mixture of 12% clamshell ash reached the optimum value of soaked design California Bearing Ratio and free compressive strength in Unconfined Compression Test which were 8.13% and 2.39 kg/cm2.
Geographical information system and satellite imagery for landslides analysis in Karo Regency based on human factors
Authors: Hastuty Ika Puji , Ellysses Pratama Oktarino
Published: April 2021

Mapping of landslide potential areas was carried out in Karo Regency using an estimation model based on the Minister of Public Works Regulation No.22 of 2007. This regulation states that human activity is one of the aspects that causes landslides to occur. There are 7 factors in human activity that can cause landslides, namely; cropping patterns, excavating and cutting slopes, pond construction, slope drainage, building construction, population density, and mitigation efforts. All of these indicators are searched for their respective scores using the Q-Gis application which produces a total score to determine the class of landslide hazard levels. Based on the analysis, the level of landslide hazard in Karo Regency is divided into 3 classes, namely; low hazard level with an area of 1699.01 km2 covering the sub-districts of Mardingding, Laubelang, Tigabinaga, Juhar, Munte, Kutabuluh, and Tiganderket. The moderate hazard level with an area of 259.34 km2 covers the sub-districts of Payung, Simpang Empat, Naman Teran, Merdeka, Brand, and Barusjahe. The high hazard level with an area of 168.77 km2 includes the sub-districts of Kabanjahe, Berastagi, Tigapanah, and Dolat Rayat.
Design and analysis of RC corbel based on SNI 2847:2019 and analysed using computer aided strut-and-tie model
Authors: Aswin M , Sonny  , Tonny
Published: April 2021

In this study, the corbel has been reviewed by considering its design and analysis based on Strut-and-Tie Model (STM). Many studies on corbels had been carried out in order to obtain an effective design approach. SNI 2847-2019 is one code that regulate to design and analyse corbel using STM. For initial stage, dimensions and steel reinforcements of corbel are designed using SNI 2847-2019 based on the empirical formulas. Afterward, design and analysis corbel were conducted using two different truss models. Aside from that, the Computer Aided Strut and Tie (CAST) software was applied on last analysis stage. Each analysis was required to generate the force ratio (FR), so it can be determined reliability of the used truss models. The design results based on the used models exhibited that the steel reinforcements of corbel are quite similar. In addition, the average force ratio for Model-1 and Model-2 are gained of 0.6204 and 0.6147, respectively. Meanwhile, the CAST analysis results also provided similar force ratio, namely 0.5805 and 0.5985 for each Model-1 and Model-2. Accordingly, STM and CAST can be used to design and analyse corbels.
Effect of use of corn leaf ash on concrete compressive strength
Authors: Aswin M , Maranatha E S , Nola L
Published: April 2021

Cement as one of concrete materials can cause the negative effect on environmental, starting from taking raw materials, production process to the resulting ash pollution. Therefore, it needs an alternative material that can be used as a substitute material of cement. Potentially, organic waste can be utilized, such as corn leaf, rice husks, palm oil waste, etc. The corn leaves are one organic waste on agricultural area which still very poorly in processing. Accordingly, this study will investigate utilizing the corn leaf ash on the concrete. The corn leaf ash was used as the cement replacement material (CRM). There are eight different percentages, namely 0%; 2.5%; 5%; 7.5%; 10%; 12.5%; 15% and 17.5%. The concretes-based corn leaf ash (ADJ) were tested at the curing ages of 7, 14, and 28 days. The test results showed that the compressive strength of ADJ of 2.5%, 5% and 7.5% increased. ADJ of 7.5% provided the maximum compressive strength. These results proved that corn leaf ash can be used as CRM.
Design of RC deep beam based on SNI 2847:2019 and analysed using STM and CAST
Authors: Aswin Muhammad , Tonny  , Sonny
Published: April 2021

Up to present, many studies and researches on reinforced concrete (RC) deep beams had been carried out in order to obtain an effective design approach. The strut-and-tie model is the most widely known and has even been included in various design codes. SNI 2847:2013 lately introduced new code provisions in designing on RC deep beam which is improved in SNI 2847:2019. Design which using the manual calculations takes quite a lot of time, accordingly, for saving time of design and analysis, the modelling program such as CAST (Computer Aided Strut and Tie) can be used. CAST is Strut-and-Tie (STM)-based, easy to be used, and presents a complete package of both design and analytical tools. This study is aim to introduce Indonesian code (namely SNI 2847:2019) in design and analysis of RC deep beam based on STM, which analysed by using CAST. The results have shown that design and analysis based on SNI 2847:2019 quite effective. The force ratio of analysis results either STM and CAST is less than 1 (one), meaning that the design result can be applied.
Optimization of water flow speed in dams
Authors: Tarihoran Lusiana , Tulus  , Sawalluddin
Published: April 2021

Utilization of the dam in controlling the flow of water is the basis for researchers to obtain optimal results of fluid dynamics in the levee. Base on the simulation results, using the COMSOL Multiphysics 5.5 software that the dam model can withstand shifts at a maximum point of 12 with a computing time of 1.9 s. if the shifting continues it will result in the collapse of the dam so that a barrier material is a gift that can withstand the shifting value of the dam material.
Groundwater feasibility test system by using wireless sensor network
Authors: Andayani U , Hizriadi A , Junaidi A
Published: April 2021

Water is one of the most important natural resources for human life. Water is used by the community for bathing, drinking, cooking and for other consumptive needs. Therefore, the water quality must be maintained cleanly. It is not uncommon to find water that is not suitable for use because it is turbid and smelly from its source. Things that must be considered to assess good water quality are pH, oxygen levels dissolved in water, conductivity, water temperature, water turbidity, salinity (salt content), zinc content and so on. The testing of groundwater quality is a better alternative than the testing that has been done manually and requires expensive costs. The measuring devices are made by using sensor circuit that is controlled by Arduino. Monitoring is done by using a web application that is stored on a server where the server also communicates with Arduino with the help of the SIM800L module. The results showed that the system ran well. The sensors succeed in detecting water quality and data communication between sensors, servers and clients ran well.
Application of Geographic Information System (GIS) for mapping of spatial distribution characteristics of the Sumatran Tigers (Panthera tigris sumatrae) prey in Besitang
Authors: Sulistiyono N , Maulana M I , Patana P , Purwoko A
Published: April 2021

This research is an example of GIS applications used in the field of conservation and landscape ecology. Sumatran tiger habitat management begins with knowing Sumatran tiger prey distribution. Information on Sumatran tiger prey distribution will be very useful in identifying the suitability of habitat for Sumatran tiger. This study objective to determine the spatial distribution of Sumatran tiger prey in Besitang forest. The method used is to overlay the coordinates of the tiger prey findings with the trigger factors that influence the distribution of Sumatran tiger prey using GIS. The results showed animals prey of Sumatran tiger in the Besitang area occurs mostly in sloping areas with low topography and regions that are relatively far to the road and near to the river