bluuebunny/crossref_metadata_2025 huggingface dataset:
Research in system design of AC and DC distribution network based on flexible substation
Authors: Fu Shouqiang , Chen Xiangyu , Yang Lin , Liu Haijun , Song Jieying , Qi Huanhuan , Chen Lei
Published: September 2020

In recent years, distribution network is developing rapidly from current to future advanced form. Under the tendency, this article puts forward a new AC and DC distribution network technology based on flexible substation. There is no mature design experience and complete theory for designing, equipment manufacturing and engineering construction, etc. in this technology. In this paper, system design method of AC and DC distribution network based on flexible substation are given systematically. And design of overall system, key equipment parameters, control and protection are researched and discussed. All of the research results above are adopted in the first AC and DC distribution network demonstration project based on flexible substation. The paper will provide theoretical and experimental experience for system design in the future AC and DC distribution network projects.
Research on nondestructive measurement solving algorithm based on grid slice volume
Authors: Gan Yong , Luan Junkai , Zhang Qiufeng , Jia Cuiyun
Published: September 2020

In this paper, an improved discrete binary particle swarm optimization (BPSO) for large scale 0-1 integer programming is proposed. Firstly, a large-scale 0-1 integer programming model based on the multi-directional slice volume of the virtual grid element is constructed, and the optimization objective function is constructed to change the problem of solving the equations into the problem of seeking the optimal solution. Secondly, the 0-1 model intelligent solution algorithm based on the improved BPSO algorithm is designed, and the model solution system based on the grid slice volume measurement is designed. Finally, through the analysis of the experimental results, it shows that the improved discrete particle swarm optimization algorithm has a significant improvement on the convergence and calculation efficiency of the fitness function, which shows that the algorithm has a good optimization performance.
Design of “One-key” security measures system for smart substation
Authors: Jin Xinming , Ren Jiangbo , Bu Mingxin , Tan Chang , Chen Haibin , Geng Shaobo , Mao Jianzhong
Published: September 2020

With the continuous advancement of technology and the ever-increasing demand for information digitization in power systems, smart substations have become the most mainstream substations currently used in China. The secondary circuit and pressure plate of the intelligent substation are virtual forms constructed by internal software. There is no obvious electrical disconnection point, so there is a big difference in operation and maintenance and repair methods from conventional substations. Combined with the requirements of the intelligent station maintenance business, this paper proposes to deploy a “one-click” security system in the station control layer monitoring system of the intelligent substation. This system is only used as an additional module and does not depend on the software and hardware structure of the station control layer. It is of great significance to effectively improve the efficiency of intelligent secondary equipment operation inspection and better guarantee the safe and stable operation of the power grid.
Design of multi-parameter auto-detecting instrument system for hydrological hole pumping test based on single-chip microcomputer
Authors: Jiang Shanchao , Wang Liming , Yang Bengong
Published: September 2020

In order to meet the requirements of modern hydrogeo-logic investigation, one multi-parameter auto-detecting instrument system for hydrological hole pumping test based on single-chip microcomputer is designed. The pumping test system contains one lower computer module and one upper computer module. The lower computer module uses the STM32 single chip microcomputer as the central module of the controller, supplemented by the sensor module, the power module, the communication module and the display module to realize the automatic detection of the multi-parameters of the hydrological hole pumping test It can display the information of pumping speed, water level, water temperature and water flow in real time and realize the function of pumping timing switch. The upper computer module allows users to check hydrological hole pumping test information and control the whole system operation. The information transmission between the lower computer module and the upper computer module is completed by Narrow Band Internet of Things (NB-Iot). By analyzing the data of pumping test system after compensation, the max relative error of liquid level is all less than 1%. All these data confirm that the pumping test system proposed in this paper has certain application value.
Study on transient electric field of multi-layer composite insulation structure during polarity reversal
Authors: Zhang Shiling
Published: September 2020

Outgoing line device is an important structure of converter transformer. Multilayer composite insulation structure is widely used in the outgoing line device. Polarity reversal is special working state of converter transformer. In the process of polarity reversal, due to the influence of the space charge on the interface of composite insulation structure, there will be instantaneous high field strength, which threatens the normal operation of the outgoing line structure. In this paper, starting from the typical multi-layer composite insulation structure in the outgoing line device, the change rule of interface space charge and transient electric field in different polarity reversal time is analyzed under the condition of the equal temperature and temperature gradient. On this basis, the research object of the overall composite insulation structure of the outgoing line device is analyzed, and the change rule of the transient electric field in the process of polarity reversal is analyzed. The research in this paper can provide a theoretical basis for the development of the outgoing line structure of converter transformer.
Load reduction algorithm for power grid low-frequency optimization
Authors: Wang Shunjiang , Xu Huiwen , Pu Baoming , Ge Weichun , Liu Qianwei
Published: September 2020

Dynamic monitoring and effective control of system frequency is the key to ensure the normal operation of power system. In this paper, a hierarchical load shedding algorithm model is constructed, which can prevent the frequency from continuously decreasing when the system affects stability due to increased load, so as to avoid large area blackouts and system collapse. It is of great significance to the safe and stable operation of power system and the national economy. It has opened up a train of thought for studying the current system frequency control methods in smart grid.
Research on operational effectiveness evaluation based on information entropy method
Authors: Wang Jianjun , Yu Tao , Liu Xiaolin , Meng Su
Published: September 2020

In the face of the future systematic warfare pattern and the development demand of argumentation and demonstration of equipment system in China, it is of great significance to carry out the research of equipment system in order to realize the transformation from single platform technology advantage to combat system capability advantage. Equipment system integrates many factors, such as combat mission requirements, equipment operational capability and weapon operational allocation. In order to construct and optimize equipment system efficiently, it is often necessary to rapidly and dynamically evaluate the operational effectiveness of equipment system. Therefore, the scientific and effective evaluation method of operational effectiveness of equipment system has important reference value for optimizing the performance of weapons and equipment and choosing the direction of equipment pre-research.
False data injection attacks detection on power systems with convolutional neural network
Authors: Lu Min , Wang Lijian , Cao Zhangjie , Zhao Youguo , Sui Xiangyang
Published: September 2020

False data injection attack (FDIA) could manipulate measurement information collected by supervisory control and data acquisition (SCADA) system, which tempers with decisions of power grid and threatens the state estimation of smart grid. Aiming at the state estimation of smart grid, the principle of FDIA under the AC power flow model is studied and a FDIA detection model based on improved convolutional neural network CNN is constructed By adding the gate recurrent unit (GRU) to the fully connected layer in CNN, the CNN-GRU network is designed to train and update network parameters based on historical measurement data of power grid, and extract spatial and temporal characteristics of the data to implement efficient and real-time FDIA detector. Finally, in the IEEE 118 bus test systems, experiments are carried out to verify the effectiveness of the proposed method.
Software implementation of automatic fault identification based on the Duval Pentagon
Authors: Hu Hong , Wang Dong , Fu Jing , Mao Yanfang , Zhang Ziwei , Wu Denghai
Published: September 2020

Dissolved Gas Analysis (DGA) is one of the most widely used monitoring technology for oil immersed power transformers. The Duval Pentagon method is a graphic interpretation method of DGA. Besides the six typical faults usually interpreted by DGA, this method also can be used alone to bring auxiliary information about the internal faults of power transformers. Based on Duval Pentagon method, this paper presents a detailed software implementation process of automatic fault identification for power transformers. Moreover, this paper also offers clear threshold conditions which indicate the abnormality of DGA results before applying the Duval Pentagon method to improve the practical use of this DGA interpretation method. Thus, the program developed by this paper can provide a commercial system of DGA interpretation.
The multi-objective optimal allocation method of static var compensator based on transient voltage security control
Authors: Zhu Yongchang , Liao Weiping , Nie Chunhong , Xie Wuchao , Xu Jianxiong , Li Yun
Published: September 2020

Based on the detailed consideration of the dynamic characteristics of Static Var Compensator (SVC), the mathematical method for installing location and optimal capacity of SVC considering transient voltage security is proposed. Firstly, the trajectory sensitivity index is used to determine the key fault set and SVC candidate location. Then, transient voltage security constraint of the bus voltage is restored to 0.75pu within 1s and the bus voltage is restored to 0.9pu within 3s after remove fault, Finally, considering the transient voltage recovery characteristics and dynamic characteristics of SVC, the minimum of bus voltage deviation after fault removed and minimum of installtion capacity of SVC as objective function for hybrid optimal allocation model. The bus voltage and capacity of SVC are introduced as variables into the Crisscross Optimization Algorithm (CSO) for solving. The effectiveness of the proposed SVC installation location and capacity optimization method is verified by the time domain simulation of the IEEE39-bus system.
Vital signs monitoring system based on piezoelectric film sensors
Authors: Xu Jiyong , Wang Yan , Li Bin , Bian Lipan
Published: September 2020

The demand for health services for the elderly has become an urgent problem to be solved. In order to solve the problems of elderly people who are prone to sudden disease during sleep, difficulty in night care, and the unconstrained requirements for health monitoring, an unconstrained vital signs mattress monitoring system was proposed. An intelligent mattress with built-in thin film piezoelectric sensors was developed to realize the real-time monitoring of vital signs such as heart rate, respiratory rate and body movement state. At the same time, medical and health resources are integrated to provide personalized and precision health care services for the elderly including safety monitoring, health management, etc. and build a smart health and elderly care service system. The experimental application shows that the system can effectively prevent accidents, improve both the efficiency of care and the level of health care services.
Research on full-bridge LCL resonant converter as constant current source in the ZVS condition
Authors: Xue Tao , Hu Xiangnan , Fang Chun’en , Zeng Chunyan , Fu Xuhui , Zhang Ning , Chen Junping
Published: September 2020

A LCL-based resonant converter is shown to behave as a constant-current source when operated at resonant frequency in this paper. This paper focuses on the realization of zero voltage switching (ZVS) in the case of constant-current in LCL resonant converter and how to reduce the influence of high harmonics on the output current. First, the principle of LCL resonant converter as a constant-current source is described. Second, when the switching frequency of the converter deviates from the resonant frequency point, the current gain curves corresponding to different quality factor Q and the boundary curves realizing ZVS turn-on are analyzed. Third, the influence of the ratio (m) of resonant inductors on the output current of the converter and ZVS turn-on is analyzed, and the value of m is determined. Finally, Pexprt software was used to design the magnetic component model, and combined with Simplorer software for combined-simulation. A simulation circuit model with output 80W/0.32A was designed and experimental results are presented. The correctness of the theoretical analysis has been verified.
Low signal-to-noise ratio speech classification with wavelet
Authors: Huang Yeguang , Peng Yifen , Zhao Wenjing , Cao Zhong
Published: September 2020

This paper evaluates the potential of wavelet in low signal-to-noise ratio (SNR) speech classification. A wavelet feature extraction method is proposed, which includes wavelet analysis, wavelet denoising and sliding variance. The potential of wavelet feature extraction method is evaluated on two different datasets with Convolutional Neural Network. The results of our model and comparation show that the performance is significantly improving comparing with other state-of-the-art approaches.
A function detection method of MMC SM in VSC-HVDC
Authors: Chen Kun , Yao Qixin , Ye Pangqi , Dai Weiqian , Wang Ting
Published: September 2020

Aiming at the problems of large workload, low efficiency and incomplete function coverage in the maintenance process of VSC-HVDC project, this paper studies the SM detection technology of MMC. Firstly, it analyzes the background and significance of this research, then based on the elaboration of the working principle of SM, a SM function detection method is proposed. This method can not only realize the automatic detection of multiple mmc-sms, but also cover all the power components except the thyristor of SM, which greatly simplifies and improves the detection steps and efficiency. The feasibility and effectiveness of the method are verified by simulation analysis.
Speed sensorless control employing adaptive sliding mode adjustable model MRAS for induction motors at low speed range
Authors: Li Jie , Wang Dong , Yang Xiaoxiao
Published: September 2020

For the sensorless speed control of induction motors, at low speed range, there exist the common problems such as low speed estimation accuracy, weak loading capacity and poor dynamic performance. When the flux-based model reference adaptive system methods are adopted, the performance of the flux estimation will determine the accuracy of the speed estimation to a large extent. In this paper, an adaptive sliding mode observer was introduced to replace the adjustable model of the traditional model reference adaptive system. The adaptive gain is designed in order to estimate the flux more accurately, and a new speed adaptive law is proposed to improve the dynamic performance and the accuracy of the speed estimation at low speed range. Simulation results verify the correctness and effectiveness of the proposed method.
Multi-objective flexible job shop scheduling problem with triple bottom line theory-based sustainable objectives
Authors: Cao Ya , Zhang Zhenzhong , Guo Zhaoxia
Published: September 2020

The triple bottom line theory (TBL) is widely used in the field of sustainable development research. Based on the triple bottom line theory, this paper investigates a multi-objective flexible job shop scheduling problem with the consideration of sustainable objectives. A multi-population evolutionary algorithm with single-objective guide (MPEA/SG) is modified to solve this problem effectively by extending the MPEA/SG to discrete optimization problems. Our experiments show that considering TBL-based objectives in job shop scheduling is more conducive to the sustainability of the production process, and can effectively reduce the carbon footprint, E/T penalty cost and income difference.
Flow field simulation of grain milling based on fluent
Authors: Mo Haijun , Ling Tao , Hong Rongbin
Published: September 2020

In order to study the flow field characteristics and pressure distribution in the grinding chamber during the working process of the grain milling machine of the grain mill, explore the influence of different working parameters of the milling mechanism on the milling effect, and study the use of Fluent to move the milling mechanism. The numerical simulation of the grinding flow field under different working parameters such as 750 r/min, 1000 r/min, 1500 r/min and feeding speeds of 0.5 kg/min, 0.75 kg/min and 1 kg/min were carried out. The results show that the dynamic pressure contour in the flow field is distributed in a ring shape, and its value increases as the radius of the grinding disc increases and the disc gap decreases. When the shape of the grinding disc changes, the dynamic pressure value will increase sharply, that is, the pressure of the powder particles increases, and it is more likely to be broken. Therefore, the shape of the grinding disc can be changed to increase the dynamic pressure and improve the grinding effect. When the disc clearance is 0.05 mm, the optimum grinding effect is obtained when the rotating disc speed is 1500 r/min, and the maximum grinding speed is between 0.5 kg/min and 0.75 kg/min.
Multi-equipment maintenance decision-making method for high temperature reactor based on maintenance event correlation
Authors: Che Shuping , Gao Jianyong , Zhang Yanpeng , Geng Jie
Published: September 2020

The composition of the high temperature reactor system is complex, effective maintenance management strategy can reduce the number of shutdowns and reduce maintenance costs during the operation of the equipment and caused by deterioration, improve system reliability, and also avoid system failures, maintain or restore the system to the most appropriate standard of reliability, availability and safety. This paper proposes a methodology on maintenance decision making with target of minimal downtime by analyse the associated relationships of different maintenance activities to realize merge maintenance.
Study on straightness prediction of centerless grinding of slender rod based on PCA and Markov
Authors: Chen Xinchun , Ding Peng , Wang Can , Yan Naiqing
Published: September 2020

In order to optimize the processing parameters of slender rods and achieve high-precision machining, a method of straightness prediction of centerless grinding based on PCA and Markov is proposed. A straightness measuring device for slender rod is developed to collect data. The accumulated straightness data is divided into typical processing conditions. The parameters that affect the straightness of centerless grinding of slender rod are analyzed based on PCA. According to the correlation between the parameters and the degree of influence on the straightness, the construction of the processing conditions is further simplified. On this basis, the straightness prediction model based on PCA and Markov is established to predict the processing conditions of centerless grinding of slender rods. Taking the centerless grinding of the piston rod of a hydraulic cylinder as an example, the machining experimental research is conducted. The predictive value is compared with the actual measured value, and the result shows that the average error rate is 3.94%, which indicates the effectiveness of the prediction method and meets the needs of actual production. This study provided technical support for parameters optimization of centerless grinding of slender rods parameter optimization and high-precision machining.
In Situ estimate of ultimate tensile strength for part optimization in extrusion-based additive manufacturing
Authors: Gooshki Sadegh Nouri , Hough Fabian , Limoge Damas W , Nirmaleswaran Aswin Raghav , Pinsky Vadim , Putman Matthew
Published: September 2020

Uncertainty in the final mechanical characteristics of an extrusion-based additive manufacturing process is a major challenge for the field. Estimating these mechanical characteristics of the specimen during printing can save cost and resources, allowing for the application of optimization methods to correct for natural error. We propose a deep learning based computer vision approach to continuously estimate the tensile strength using recent images of each printed layer, and acting to critique the efficacy of the extrusion process. This predictive model is useful for in situ part optimization, maximizing the output prediction.
Simulation study on steel pipe deformation behavior in retained mandrel pipe mill
Authors: Zhang Dazhi , Guan Mingsheng , Zhang Qingdong , Wang Aiguo , Zhou Xinliang
Published: September 2020

Continuous rolling technology of seamless steel pipe is the leading technology in the production of steel pipes in recent years. However, due to the complicated pipe rolling process, the rolling parameters must be adjusted according to the rolling conditions after many trials of rolling. This paper focuses on a Φ180mm retained mandrel pipe mill, and the continuous rolling process finite element analysis model of seamless steel pipe is established by using ABAQUS software. The finite element model is validated by the measured wall thickness and pipe diameter data of industrial production, and the model is designed to reveal the evolution of rolling pressure distribution, metal flow, strain, wall thickness and pipe diameter during the continuous rolling process. The simulation results support key structural design of the rolling mill, the determination of rolling process parameters and the optimization of process parameters in engineering commissioning.
Microcracks UHMWPE assessment using the wavelet transform
Authors: Pérez-Martínez Israel , Torres-San Miguel Christopher René , Rodríguez-Martínez Rafael , Murillo-Martínez Cesar
Published: September 2020

Previous studies have indicated that one of the main problems in the prosthesis inserts of ultra-high-molecular-weight polyethylene UHMWPE, is the destruction apparently by delamination, due to wear. Fatigue in polymeric materials is the leading cause of failure due to the cyclic or random application of the load in a component. Damage inspection techniques, such as ultrasound and microtomography, are used to detect internal microscopic damage. However, the high cost of these two techniques allows us to propose new inspection methods. The present work shows a simulation of signal processing techniques, as well as the use of the wavelet transform to obtain a representative image of the possible emergence of microcracks. The results show a low-cost test of the acoustic impedance contrasts, which represent the changes in velocity propagation in the medium, which translates into cracking.
Role of temperature on bio-printability of gelatin methacryloyl bioink in two-step cross-linking strategy for tissue engineering applications
Authors: Janmaleki Mohsen , Liu Jun , Kamkar Milad , Azarmanesh Milad , Sundararaj Uttandaraman , Nezhad Amir Sanati
Published: September 2020

Additive manufacturing has shown promising results in reconstructing three-dimensional (3D) living tissues for various applications, including tissue engineering, regenerative medicine, drug discovery, and high-throughput drug screening. In extrusion-based bioprinters, stable formation of filaments and high-fidelity deposition of bioinks are the primary challenges in fabrication of physiologically relevant tissue constructs. Among various bioinks, gelatin methacryloyl (GelMA) is known as a photocurable and physicochemically tunable hydrogel with a demonstrated biocompatibility and tunable biodegradation properties. The two-step crosslinking of GelMA (reversible thermal gelation and permanent photo-crosslinking) has attracted researchers to make complex tissue constructs. Despite promising results in filament formation and printability of this hydrogel, the effect of temperature on physicochemical properties, cytocompatibility, and biodegradation of the hydrogel are to be investigated. This work studies the effect of thermoreversible, physical crosslinking on printability of GelMA. The results of 3D printing of GelMA at different temperatures followed by irreversible chemical photo-crosslinking show that the decrease in temperature improves the filament formation and shape fidelity of the deposited hydrogel, particularly at the temperatures around 15 °C. Time dependant mechanical testing of the printed samples revealed that decreasing the extruding temperature increases the elastic properties of the extruded filaments. Furthermore, our novel approach in minimizing the slippage effect during rheological study enabled to measure changes in linear and non-linear viscoelastic properties of the printed samples at different temperatures. A considerable increase in storage modulus of the extruded samples printed at lower temperatures confirms their higher solid behavior. Scanning electron microscopy revealed a remarkable decrease in porosity of the extruded hydrogels by decreasing the temperature. Chemical analysis by Fourier-transform infrared spectroscopy and circular dichroism showed a direct relationship between the coil-helix transition in hydrogel macromers and its physical alterations. Finally, biodegradation and cytocompatibility of the extruded hydrogels decreased at lower extruding temperatures.
Anthropogenic influence would increase intense snowfall events over parts of the Northern Hemisphere in the future
Authors: Chen Huopo , Sun Jianqi , Lin Wenqing
Published: September 2020

Snowfall is an important element of the climate system and generally has particularly large economic and human impacts. Simulations with climate models have indicated a decline in mean snowfall with warming in most regions. The response of intense snowfall events to a changing climate, however, is unclear. Thus, the degree which anthropogenic influence is responsible for intense snowfall change and how intense snowfall will respond to the changing climate in the future are addressed here using new simulations from Coupled Model Intercomparison Project phase 6 models. The results show that anthropogenic influences on changes in snowfall are detectable across the lands of the Northern Hemisphere and generally result in a decreasing trend in snowfall events. However, increased anthropogenic activity has increased intense snowfall occurrences over most parts of Asia, North America, and Greenland. With additional warming in the future, while the length of the snowy season will be shortened and the areas where snowfall occurs will be reduced, the occurrence probability of an intense snowfall event is projected to significantly increase with a level of high confidence over these regions by the end of this century. This suggests that these regions, including most parts of northern China, would suffer from more intense snowfall events in the future due to a continuous increase in anthropogenic influence.
The effect of wood ash and styrofoam on the characteristics of AC-WC mixture
Authors: Yusputri R M , Saleh S M , Isya M
Published: September 2020

In this study, two types of substitutions, wood ash, and styrofoam, were used in asphalt concrete. The substitution of wood ash and styrofoam for asphalt concrete’s filler is expected to enrich the variations of the asphalt concrete material as well as to reduce the existing industrial waste. This study objective is to determine the effect of the asphalt mixture, which filler was substituted with the wood ash, on the Marshall test results. The initial stage of the research is to examine the physical properties of the asphalt and aggregate. Then, the optimum asphalt content (OAC) of the asphalt mixture was estimated. Then, the asphalt mixture’s filler was substituted with the wood ash and the asphalt material was substituted with the styrofoam. The result of this study is the best combination of the wood ash in asphalt mixture, which is 25% of the total filler, and the best combination of the styrofoam in asphalt mixture, which is 9% of the total asphalt content. With these best combinations of the wood ash and the styrofoam, the obtained Marshall stability of the asphalt concrete was 1,249.01 kg, which fulfills the ‘2018 Bina Marga’ requirement.
Travel cost budget distributions among household life stages considering bus users in Banda Aceh
Authors: Putri A , Sugiarto S , Saleh S M , Basrin D
Published: September 2020

This study aims to investigate the average travel cost budget (TCB) distributions among household life stages (HLS) groups considering the bus users of Trans-Koetaradja in Banda Aceh, capital of Aceh province. This research was conducted within three corridors of Trans Koetaradja. The onboard survey is performed to collect bus users related information such as their monthly travel budget, socio-economic attributes, and travel/mobility characteristics. In this study, we only consider to analysis the distributions and characteristics obtained data sets by deeply investigating socio-demographics and travel attributes of bus users. The analysis result reveals that the group 3 (families with pre-school children) spent the highest average of TCB (0.442 million IDR/month) and group 1 (single person) spent the lowest TCB (0.280 million IDR/month). While group 2 (childless couple) has portion the lowest average of TCB about 10.2% from their monthly income, and group 3 (families with pre-school children) has shared the highest TCB accounting up to 14.4% from their monthly income compared to the remaining groups. This result depicts that an average TCB across HLS groups is considerably high, especially early household life stages development. It is may partially due to a limitation on their monthly income and lack of affordable transport mode for them.
The analysis of roadside obstacles to the performance of Syiah Kuala Street
Authors: Musita R , Anggraini R , Sugiarto S
Published: September 2020

Urban roads are the segments that have permanent and continuous development, at least on one side of the road. The purpose of this study is to evaluate the performance of the road due to side constraints on Syiah Kuala Street, to find out how much the operational costs of the vehicle (BOK) based on the side obstacles on Syiah Kuala Street section, and to find out traffic management recommendations by considering subscriber scenarios. The research result indicates that the maximum volume of the vehicle at peak hour is 1987 pcu/hour (on Monday), and the corresponding roadside obstacle is 551.7, which is categorized in the high class. Based on this data analysis result, it is shown that the capacity on Monday is 1998 pcu/hour with the corresponding degree of saturation as much as 0.99. As a result, the level of service is E (unstable flow, obstructed, with intolerable delay). The average travel speed is around 25 km/hour; v/c ratio is 0.85 - 1.00.
The effect of porous zigzag-type breakwaters on the coastline changes in Neuheun village, Aceh
Authors: Pagihariadi P , Fatimah E , Syamsidik S
Published: September 2020

The process of changing the coastline has always been a challenge for coastal communities. Beach erosion has been a threat with the coastline withdrawing from its previous position. Coastal protection buildings are needed to overcome coastal erosion problems, and alternative construction also needs to be developed. The zig-zag type porous breakwater is quite effective in reducing erosion based on several small-scale physical models that have been developed. Therefore a prototype was built and tested to observe its usefulness, and how it was applied in the field. This study aims to assess the effect of installing zigzag type porous breakwaters on coastline changes. This research began with the installation of construction and continued with observing changes in the coastline. Observations are carried out periodically at any time, to see changes in the contour of the beach that occurs. Observations were made by leveling the beach surface against several transverse profiles. Changes in coastline due to construction will be analyzed by looking at the relation to the wind direction. The results obtained from several observations show that the construction of a zig-zag type porous breakwater has a positive effect in reducing erosion, as long as the breakwater distance with the coastline does not exceed the breakwater length.
Joint operation of parallel reservoir with interconnected tunnel
Authors: Iqbal K , Limantara L M , Soetopo W , Andawayanti U
Published: September 2020

Reservoir operation is strongly influenced by water balance conditions in the catchment area. The amount of inflow, reservoir capacity, and water requirement are major factors in arranging the reservoir operation rules. The purpose of this research is to obtain the extent of the parallel reservoir operation reliability that performed simultaneously by utilizing water transfer from wet to dry watershed. Simulation method used to operate the parallel reservoir with interconnecting tunnel between. From simulated results on three seasons, there are obtained that the water potential to be transferred to the dry watershed. By utilizing this water potential, further simulation for 25 years will come to see the reliability of the joint operating rule in this location.
Hard bearing layers identification of escape hill design for facing tsunami - earthquake disaster at Deah Baroe rural area for natural disaster risk reduction
Authors: Munirwansyah M , Munirwan R P , Sungkar M , Yunita H , Munirwan H , Saharuddin  , Fachrurrazi F , Widilestari W
Published: September 2020

Aceh is surrounded by the Indo-Australia and Euro-Asia subduction plate, which has a profound effect on the occurrence of large tectonic earthquakes above 5 SR which may cause the tsunami. The tsunami which occurred in Aceh on December 26th, 2004 had the large number of the casualties during the 9.3 magnitude earthquake was affected by the lack of temporary evacuation like escape hill. The government’s lack of preparedness for escape hill in order to deal with several serious threats such as the earthquake which may cause tsunami disaster in Banda Aceh. To deal with this serious threat, it is necessary to prepare a place of salvation to face the tsunami, in this case is an escape hill (artificial hill). The objective of this research is to determine the carrying capacity of the hard bearing layers identification of escape hill design and the amount of the settlement, due to the load of the embankment height (Hcrit) and the safety factor value. This research is conducted in Ulee Lheue Banda Aceh which was calculated by the Plaxis 8.2 finite element analysis. The research results found that the settlement value of 17.45 cm still within in the tolerance limits and the bearing stratum is still able to withstand the embankment load. Furthermore, the safety factor value is 1.04 shows that the bearing stratum is still in the safe condition (hard soil) and it does not indicate the failure.
Passenger’s choice in responding to inter-city railway operation for Makassar - Parepare line: a conditional logit model based on stated preference method
Authors: Ramli M I , Yatmar H , Dharmowijoyo D B E , Adisasmita S A , Pasra M , Arif A , Dwiatmoko H , Irawan M Z
Published: September 2020

The present paper aims to model the passenger’s choice in responding to the inter-city railway operation for Makassar-Parepare line. The railway line is the first railway track in Eastern Part of Indonesia, and it is still under construction. In this regard, the study attempted to construct the passenger’s preferences through a conditional logit model approach based on the stated preference method. The study considered some main attributes of transport mode services, i.e., travel cost, travel time, and frequency. In further, the study also taking account into the model two additional attributes of the mode, i.e., transfer travel time and transfer travel cost. The data collection of the study carried out an interview method using questionnaire sheet based the stated preference method. The study experimented with varying the level of service for the main attributes of the two available travel modes, i.e., railway and private car modes. The study results showed that passengers prefer to choose one of both travel modes when the mode has travel time faster than the other one, as well as for the lower travel cost. In addition, the inter-city travelers more considered the transfer travel cost attribute than the transfer travel time attribute, when they face both travel mode choice, the new railway mode, and the existing private car mode.
Effect of utilizing geopolymer fly ash on potential and corrosion rate of reinforcement in high-strength concrete
Authors: Aulia T B , Muttaqin M , Afifuddin M , Zaki M , Firdaus
Published: September 2020

With the increasing use of high-strength reinforced concretes as a structural element of construction, their resistance to corrosion in environmental conditions needs to be studied. It is well known that cement manufacturing at plants is un-environmental friendly due to plenty of fuel consumption and CO2 emission to the atmosphere leading to greenhouse effect. Therefore, substituting cement with environmentally friendly natural materials and natural wastes become a smart solution. This study aims to measure the potential level and corrosion rate of reinforcing steel in high-strength concrete with variations in cement replacement by geopolymer fly ash, environmental conditions, and concrete covering thickness. Corrosion potential measurement was carried out with the half-cell potential mapping method, while the corrosion rate used the linear polarization resistance method. Data collection was executed every two weeks during eight weeks of immersion. High-strength concrete beams with compressive strength target 70 MPa having dimension 15cm x 20cm x 80cm were substituted with 15% coal fly ash (CFA), 15% palm oil blast furnace slag fly ash (POSFA), and 10% pozzolanic fly ash (PFA) from cement weight. High-strength concrete specimens without fly ash substitution were made as a comparison (HSCWFA). It was installed 4 longitudinal reinforcement 010 mm and 7 stirrups 6 mm with a distance of 10 cm. The concrete covering thickness was 2 cm and 4 cm. Immersion medium uses artificial seawater (3.5% NaCl) and shallow well water. The results showed that specimens resulting in the lowest corrosion rate were PFA, CFA, POSFA, and HSCWFA respectively. Corrosion potential was obtained at low to medium levels, while corrosion rates were at low corrosion level criteria. It can be clearly concluded that the utilizing of a geopolymer fly ash could increase the permeability of high-strength concretes through their higher resistance to the penetration of chloride ions.
Noise mitigation based on noise barrier for railway Makassar - Parepare line
Authors: Hustim M , Ramli I , Zakaria R , Evianista E
Published: September 2020

This research aimed to analyze the noise reduction based on the noise barrier along the Makassar-Parepare railway. The measurement was conducted on Makassar-Parepare line, which consists of 4 types of areas. Six of the observation points are in residential areas, 1 point in commerce area, 1 point in the green open space area, and 1 point in the station area. Each region has 6 measurement points. So that the whole measurement points are 54 measurement points. The noise level measurement was conducted using simple SLM (sound level meter) placed at 3 meters from the side of the road with a height of 1.2 meters from the road surface and omitted the background noise by using windscreen from the SLM. Measurements were operated every 10 minutes for four-time intervals which are 06.00-09.00, 09.00-14.00, and at 14.00-17.00. The research result shows the settlement areas consisting of 36 measurement points, in which 69% has exceeded the quality standard, and 31% are still below the standard. For the green open space area which includes six measurement points, 17% has exceeded the quality standard, and 83% are still below the standard. For the commerce area and stations which consist of 6 measurement points, 100% of the areas are still below the standards. The noise barrier design could reduce the noise level 5.0 until 7.7 dB.
Steady flow in a rapidly rotating spheroid with weak precession: Part 2
Authors: Kida Shigeo
Published: September 2020

This is a continuation of our companion paper (Kida 2020b Fluid Dyn. Res.) in which the steady flow in a precessing spheroid is studied in the strong spin and weak precession limit, and the elliptic flow with uniform vorticity, the direction of which is perpendicular to the spin axis on the plane spanned by the spin and the precession axes, is shown to be excited in the interior inviscid region. In this paper we examine the boundary-layer flow connected to this elliptic flow and also the higher-order inviscid flow modified by this boundary-layer flow. The explicit expression of the velocity and pressure fields is obtained for arbitrary aspect ratiocof the polar and equatorial radii of the spheroid. The boundary-layer approximation breaks down at two critical circles on which the boundary-layer thickness as well as the normal component of velocity diverge to infinity. The flow field in the neighborhood (called the critical regions) of the critical circles is analyzed to find the same structure, up to scales, as that for a sphere. The radial component of velocity in the critical region induces the conical shear layers along the characteristic cones in the inviscid region. They reflect on the spheroid surface, and the reflection takes place endlessly in general. On the other hand, it is proved that for a spheroid of which the aspect ratio is expressed asc=3cot[(π/2)(m/n)](m/nbeing an irreducible fraction) the reflection terminates at (n − 2) times and the conical shear layers form a regular pattern. Since such special values ofcare distributed densely over all the positive numbers, we may observe practically always a regular pattern of the conical shear layers. Such closed conical shear layers are clearly visualized by the pressure field numerically calculated in the asymptotic formulation. Furthermore, the total angular momentum of the steady flow is expressed explicitly up to the non-trivial leading order for all the three components over the whole range of the aspect ratio.
Measurements of the currents induced in coaxially confronted superconducting rings
Authors: Paredes E , Galán G Briones , Veira J A , Mosqueira J , Romaní L , Domarco G
Published: September 2020

Very high currents can be induced in pairs of current-carrying superconducting rings when they are coaxially brought closer. If the currents are uniformly distributed through the cross-section of the rings their magnitude can be derived from the mutual inductance of interacting rings. However, if the currents are not uniformly distributed that calculation procedure should be no longer applicable. The aim of this paper is to report on an alternative procedure to determine the induced currents by measuring the magnetic flux density around the rings and applying the Ampre’s circuital law. Our results show that in axially confronted rings the induced currents may be significantly larger than the critical current of an isolated ring, which may be explained in terms of a reduction of the magnetic self-field.
Masters of asymmetry – lessons and perspectives from 50 years of septins
Authors: Spiliotis Elias T. , McMurray Michael A.
Published: September 2020

Septins are a unique family of GTPases, which were discovered 50 years ago as essential genes for the asymmetric cell shape and division of budding yeast. Septins assemble into filamentous nonpolar polymers, which associate with distinct membrane macrodomains and subpopulations of actin filaments and microtubules. While structurally a cytoskeleton-like element, septins function predominantly as spatial regulators of protein localization and interactions. Septin scaffolds and barriers have provided a long-standing paradigm for the generation and maintenance of asymmetry in cell membranes. Septins also promote asymmetry by regulating the spatial organization of the actin and microtubule cytoskeleton, and biasing the directionality of membrane traffic. In this 50th anniversary perspective, we highlight how septins have conserved and adapted their roles as effectors of membrane and cytoplasmic asymmetry across fungi and animals. We conclude by outlining principles of septin function as a module of symmetry breaking, which alongside the monomeric small GTPases provides a core mechanism for the biogenesis of molecular asymmetry and cell polarity.
FCSlib: an open-source tool for fluorescence fluctuation spectroscopy analysis for mobility, number and molecular brightness in R
Authors: Pinto-Cámara R , Linares A , Moreno-Gutiérrez D. S , Hernández H. O , Martínez-Reyes J. D , Rendón-Mancha J. M , Wood C. D , Guerrero A
Published: September 2020

FCSlib is an open-source R tool for fluorescence fluctuation spectroscopy data analysis. It encompasses techniques such as Fluorescence Correlation Spectroscopy, Number and Brightness, Pair Correlation Function and Pair Correlation of Molecular Brightness.

Availability and implementation

Source code available at https://cran.r-project.org/web/packages/FCSlib/ for Linux, Windows and macOS platforms. Sample data as well as a user's guide are available at https://github.com/FCSlib/FCSlib.

Supplementary information

Supplementary data are available at Bioinformatics online.
Development of assisted reproductive technologies forMus spretus†
Authors: Hasegawa Ayumi , Mochida Keiji , Matoba Shogo , Inoue Kimiko , Hama Daiki , Kadota Masayo , Hiraiwa Noriko , Yoshiki Atsushi , Ogura Atsuo
Published: September 2020

The genus Mus consists of many species with high genetic diversity. However, only one species, Mus musculus (the laboratory mouse), is common in biomedical research. The unavailability of assisted reproductive technologies (ARTs) for other Mus species might be a major reason for their limited use in laboratories. Here, we devised ARTs for Mus spretus (the Algerian mouse), a commonly used wild-derived Mus species. We found that in vitro production of M. spretus embryos was difficult because of low efficacies of superovulation with equine chorionic gonadotropin or anti-inhibin serum (AIS) (5–8 oocytes per female) and a low fertilization rate following in vitro fertilization (IVF; 15.2%). The primary cause of this was the hardening of the zona pellucida but not the sperm’s fertilizing ability, as revealed by reciprocal IVF with laboratory mice. The largest number of embryos (16 per female) were obtained when females were injected with AIS followed by human chorionic gonadotropin and estradiol injections 24 h later, and then by natural mating. These in vivo-derived 2-cell embryos could be vitrified/warmed with a high survival rate (94%) using an ethylene glycol-based solution. Importantly, more than 60% of such embryos developed into healthy offspring following interspecific embryo transfer into (C57BL/6 × C3H) F1 female mice. Thus, we have devised practical ARTs for Mus spretus mice, enabling efficient production of embryos and animals, with safe laboratory preservation of their strains. In addition, we have demonstrated that interspecific embryo transfer is possible in murine rodents.