bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization study on magnetorheological fluid components and process parameters of cluster magnetorheological finishing with dynamic magnetic field for sapphire substrates
Authors: Pan Jisheng , Zheng Kun , Yan Qiusheng , Zhang Qixiang , Lu Jiabin
Published: September 2020

Sapphire is used as the base material of high-brightness LED devices, high-speed and high-frequency wireless communication devices, and solar photovoltaic conversion chips. Its surface quality determines the performance of the device. Magnetorheological (MR) finishing can avoid scratches and surface/subsurface damage caused by uneven abrasive particles due to the viscoelasticity of the polishing pad. When MR polishing was used to polish sapphire substrates, the adaptability of the MR fluid components and the rationality of polishing process was the key to quickly obtain high-quality workpiece surface. In this study, sapphire substrates were polished using cluster MR finishing with dynamic magnetic fields formed by multiple synchronous rotation magnetic poles. The components of the MR fluid were optimized by single-factor experiments, and the polishing process parameters were optimized through orthogonal experiment. The results showed that an ultra-smooth surface of Ra 0.27 nm could be obtained when sapphire substrate was polished 8 h by using the optimized MR fluid, which contained 120 nm silica sol with a mass fraction of 8 wt% and W3 carbonyl iron powders with a mass fraction of 16 wt%, also with the optimized process parameters as the machining gap, the workpiece speed, the magnetic pole speed and the rotation speed of the polishing disc were 1 mm, 350 r min−1, 45 r min−1 and 40 r min−1, respectively.
From the Jaynes–Cummings model to non-abelian gauge theories: a guided tour for the quantum engineer
Authors: Kasper Valentin , Juzeliūnas Gediminas , Lewenstein Maciej , Jendrzejewski Fred , Zohar Erez
Published: September 2020

The design of quantum many body systems, which have to fulfill an extensive number of constraints, appears as a formidable challenge within the field of quantum simulation. Lattice gauge theories are a particular important class of quantum systems with an extensive number of local constraints and play a central role in high energy physics, condensed matter and quantum information. Whereas recent experimental progress points towards the feasibility of large-scale quantum simulation of abelian gauge theories, the quantum simulation of non-abelian gauge theories appears still elusive. In this paper we present minimal non-abelian lattice gauge theories, whereby we introduce the necessary formalism in well-known abelian gauge theories, such as the Jaynes–Cumming model. In particular, we show that certain minimal non-abelian lattice gauge theories can be mapped to three or four level systems, for which the design of a quantum simulator is standard with current technologies. Further we give an upper bound for the Hilbert space dimension of a one dimensional SU(2) lattice gauge theory, and argue that the implementation with current digital quantum computer appears feasible.
Nonlocal vibrations and instability of three-dimensionally accelerated moving nanocables
Authors: Kiani Keivan , Efazati Mahdi
Published: September 2020

By considering the small-scale parameter, bilateral vibrations of a moving nanocable with three components of velocity and axial acceleration are investigated. The equations of motion associated with the transverse vibrations are derived using the Hamilton principle in the framework of Eringen’s elasticity theory. The newly developed governing equations are then solved for natural frequencies using Galerkin approximation and the exact methods for fixed-end conditions. To ensure the accuracy of the calculations, the results of the Galerkin method are compared with those of the method, and the capability of the Galerkin method in predicting the vibrational behavior is proved. The influence of the small-scale parameter, length, tensile force, and diameter on the mechanical behavior of the three-dimensionally moving nanostructure is investigated carefully. It is observed that by increasing the small-scale parameter and the diameter, the critical speeds and the fundamental frequency would lessen. Additionally, with increasing the tensile force and the axial acceleration, the lateral stiffness of the nanocable grows, leads to an increase of the critical speed as well as the fundamental frequency.
Bifurcation of Periodic Solutions and Its Maximum Number in a Circular Mesh Antenna System with 1:2 Internal Resonance
Authors: Jiang Lishuang , Li Jing , Zhang Wei
Published: September 2020

In this paper, we study the bifurcation of periodic solutions for a four-dimensional deployable circular mesh antenna system. The tools for proving these results are the averaging theory and Brouwer degree theory. Based on constructing displacement maps, we study the bifurcation of the periodic solutions of linear center, and to discuss the maximum number of periodic solutions in certain parameter control conditions. The results in this paper are helpful to the study of nonlinear dynamic characteristics and vibration control of deployable circular mesh antenna model.
Influences of Encapsulated HfO2 Film on the Performance of Graphene Filed Effect Transistors
Authors: Zhang Zhaohao , Wei Qianhui , Li Yudong , Zhang Qingzhu
Published: September 2020

Although the sensitivity of the traditional electrolyte-gated graphene FET is high, the graphene channel is easy to be polluted because of the direct contact between graphene and electrolyte, which leads to the poor stability of the device and not reusable. Ion sensitive field-effect transistors based on graphene (G-ISFET) with top dielectric layer could address the problems. However, deposing dielectric layer on graphene channel is a kind of doping process which debases the performance of G-ISFET. Therefore, the influences from the top dielectric layer in G-ISFET are important and should be studied. In this work, a bottom gate G-ISFET is designed and fabricated, which uses graphene as channel and insulating layer HfO2 as the protective film of graphene. Besides, through a series of electrical characterization, the influence of the deposited HfO2 top layer on graphene FET is analyzed, and the device’s characters as pH sensor is further explored.
Effect of Beam Oscillating Parameters on Laser Welding of Mg/Ti Joints
Authors: Dong Wen , Huang Rongrong , Zhao Hongyun , Tan Caiwang
Published: September 2020

Laser oscillating welding of AZ91 and Ti-6Al-4V was carried out and the influence of oscillating parameters on morphology and mechanical property was investigated. The joint strength obtained with beam oscillating was enhanced compared that without oscillating. With oscillating frequency increased, welding width of Mg improved while the melting amount of Ti decreased. The tensile strength improved initially and then decreased when oscillating frequency increased.
Structural Evolution of β’-In2Se3 under Pressure
Authors: Liang Juan , Jin Haolin , Zhang Jiang , Chen Xi
Published: September 2020

The structural evolution from β’ phase to β phase of the In2Se3 under high pressure is studied by X-ray diffraction (XRD) and Raman scattering. The XRD spectra show that the crystal transforms from β’ phase to β phase at 11.5 GPa, which is consistent with the previous studies. However, the red shift of Ag
4 Raman mode shifts at pressure ranging from 8.8 GPa up to 15.2 GPa which associates with the stretching In-Se bonds under high pressure. The result indicates that the change from low-symmetric phase to high-symmetric phase of the layered In2Se3.
Influencing Factors in Regional Income Gap in Guangdong
Authors: Xie Xiuzhen , Huang Hongwu
Published: September 2020

The widening income gap may lead to a “middle income trap”. As a province of economic strength in China, Guangdong’s widening regional income gap will have a negative impact on its economic development. By adopting a time series regression research method, this paper found that changes in educational human capital and traffic facility have a significant influence on the widening regional income gap. Therefore, it is suggested to narrow the regional income gap by increasing education expenditures, allocating education expenditures in various regions, as well as planning traffic routes rationally.
Simulation of Solidification Process of BGA Tin-Lead Solder ball Based on Cellular Automaton Method
Authors: Li Xiang , Gao Tianming , Guo Shuhan , Li Yang , Huo Shixing , Wang Hengrui , Li Shuai , Zhang Tao , Li Shu
Published: September 2020

A method based on cellular automata was established to simulate the solidification process of solder balls used in ball grid array (BGA) packaging technology. For the uniform and constant temperature distribution inside the droplets, the equiaxed crystal morphology and the equiaxed crystal solute field were studied. The simulation results are also shown for solidification process with the BGA tin-lead solder ball prepared by uniform droplet spray (UDS) process under the condition that the cooling rate of is invariable.
On Living Dam Planning for Earthquake Prevention and Disaster Reduction
Authors: Li Youfang , Zhao Shigang , Qin Xue , Li Dahua
Published: September 2020

Based on the comprehensive research on the technology of “geographical name code”, “modern nonmetallic structure”, “high temperature fermentation biogas digester waste disposal power generation”, “Internet plus earthquake prevention and disaster mitigation APP” and “new theory of securities public investment”, this paper puts forward a new concept of “earthquake prevention and disaster reduction” in dam, which will obviously alleviate the shortage of farmland, cross river traffic, small hydro-power development in mountainous areas, and environmental protection waste. One belt, one road area, and the county level place code are proposed to lay the foundation for the new intelligent platform for earthquake emergency international earthquake preparedness and disaster reduction. The basic theory of securities public investment and its application in the PPP project for earthquake prevention and disaster mitigation are put forward, and the specific planning plan and budget for the construction of the dam in the poverty-stricken mountainous area are put forward. We will demonstrate the one to one belt, one road and one country. This paper is originated from practice and has a new idea, which will obviously promote the new development of human earthquake prevention and mitigation.
Facile Synthesis of Au Nanoparticles Supported on TiO2 Inverse Opals with Biosensor
Authors: Chen Zhe , Fu Ming , Wu Zheli , Li Caixia , Jiang Jingwen
Published: September 2020

In this paper, a three-dimensional porous structure of TiO2 inverse opals loaded the large area gold nanoparticles (AuNPs) was used as an advanced material for detection of L-cysteine and Avidin molecule concentrations. We think that functionalized gold nanoparticles combined with TiO2 inverse opals of low cost can couple out a characteristic reflection peak. After biomolecules were successively linked to the gold particles supported on TiO2 inverse opals, it is found that the peak position linearly red shifted with a change of avidin concentration. The lower limit of detection concentration can be up to 2x10−7M. This maybe provide a kind of biosensor for detecting biomolecules in the future.
Tebeigai Soil Conditioner Can Increase Eggplant Yield, Reduce Heavy Metal Content and Improve Soil Acidification
Authors: Huang Dongfeng , Luo Tao , Li Yu , Qiu Xiaoxuan
Published: September 2020

The acidification of farmland soil in the red soil region of South China has led to the decrease of agricultural products, quality and soil degradation, which is in urgent need of improvement. In this paper, a field trial was implemented to study the effect of applying different amount of Tebeigai soil conditioner (namely 750, 1125, 1500, 1875 and 2250 kg/ha) on eggplant’s yield, heavy metal content and basic physical and chemical properties of soil in red soil area. The results showed that: compared with the control treatment, the application of different doses of Tebeigai soil conditioner could increase eggplant yield by 15.5%~55.8%; reduce As content of eggplant fruit by 12.8%~51.8%, Cr content by 33.7%~57.1%, Pb content by 1.9%~19.2%, Cd content by 14.3%~30.4%; at the same time, the soil pH increased by 5.8%~18.6%, exchangeable acid (potential acid) decreased by 37.6%~82.3%; and the contents of available Pb, Cd and Cr were decreased by 7.0% ~ 21.6%, 15.1% ~ 29.6% and 1.0% ~ 21.4%, respectively.
Study on Fault Characteristics of Lower Cretaceous in Lishu Fault Depression of Songliao Basin
Authors: Qu Shaodong
Published: September 2020

As one of the most important geological structures, faults are widely developed in the crust, and the formation of faults is closely related to the regional stress field. The study of the fault characteristics can reflect the properties of the regional stress field in different periods. The regional stress field in Lishu fault depression, southeast uplift area of Songliao Basin is analyzed based on the statistical analysis and the study on the strike and length of the faults in different periods. The results illustrated that the Lishu fault depression went through three stages, the NW-SE extension in Huoshiling period, the left-lateral extrusion in Shahezi period, and the NW-SE extension in Yingcheng period, in which research the maximum value of regional stress field. With its special tectonic characteristics, Lishu fault depression reflects and records the tectonic regime and the main stages of innovation, transformation and evolution in geodynamic environment since the Mesozoic of northeast Asia tectonic domain.
Experimentation on Biogas Motor Generator Valves
Authors: M.E. Emetere , R. Ekelekhomen , S.A. Afolalu , S.O. Banjo
Published: September 2020

The sudden switchover from the fossil-fuel energy machineries to renewable energy would throw 13% of the work force into joblessness. It would take close to two decades to reintegrate existing energy players in developing countries to renewable energy option. In this research we proposed a green solution where existing energy player can be integrated into renewable energy option at no cost. The biogas motor generator was proposed so that the poorest homes could afford it. The technicalities of the biogas motor generator was discussed i.e., considering the vital role of control valve in sending 52% methane into the generator. It was observed that a valve of cross-sectional area 0.8 mm2 would withstand the anomalies of designing a biogas generator without the purifier chamber.
Analysis on Single Slit Diffraction Experiment Based on MATLAB Simulation
Authors: Xing Qiongyong , Li Yang
Published: September 2020

Computer simulation of optical experiments plays an important role not only in scientific and engineering calculations, but also in optical teaching. MATLAB software development tools provide a simple and efficient programming environment for computer dynamic simulation of abstract and complex physical phenomena. In this paper, based on the analysis of the mathematical model of the single slit diffraction phenomenon, a method for computer simulation of the single slit diffraction phenomenon using MATLAB development tools is proposed.
Failure Criterion and Parameter Calibration Methods of Aluminum Brass Alloy based on J-C Model
Authors: Cui Kaibo , Sun Yezun , Yuan Qingxu , Wen Zhenggang
Published: September 2020

As the impact resistance of metal varies from different material property, therefore, the failure criterion has been adopted as theoretical or empirical formula to describe the capacity of ultimate load and deformation for materials. The paper has improved Johnson-Cook failure criterion equation and identified parameters of failure criterion through combination of experimental data, analogue simulation and numerical fitting, so as to lay the foundation for simulated analysis.
Opto-Electronic Properties of Methyl-Ammonium Lead Halide: A First Principle Approach
Authors: Mehtab-Ur-Rehman  , Jin Xin , Wang Qun , Jadoon Atif Mehmood
Published: September 2020

Using first principle approach, based on Density functional theory (DFT), we have investigated the ground state opto-electronic properties of methyl-ammonium lead halide (MLH). CH3NH3PbX3 where (X=Cl, Br, I), the key materials for opto-electronic applications, especially for efficient and low cost solar cell. The halide contents are important in electronic and optical behavior such as band structure, density of states, absorption, optical conductivity etc. The nature of calculated band structure (BS) and density of states (DOS) clarify that these are semiconductor. Further-more CH3NH3PbPbI3 has effective band gape and can be utilized in opto-electronic applications especially in solar cell.
Construction of Intelligent Service Management Platform for College Sports Teams
Authors: Deng Chenliang , Tang Zhaohua , Zhao Zhangzhi
Published: September 2020

This research takes the training, competition, management and talent database of college sports teams as the entry point, and the cross theory of computer, sports and management as the basis, aiming to build the intelligent service management platform of college sports teams. In order to achieve this goal, this study combined with the survey results and big data analysis, carried out a detailed program design for the training, competition and management of college sports teams. Then, combined with the data collected by wearable devices, an intelligent service management platform for college sports teams is designed and built. The platform is used to help sports teams to carry out competition, training and management in a more convenient, efficient and scientific way, provide data support for scientific decision-making, and provide integrated information resources, interactive information network and personalized information services for scientific training, competition and management of college sports teams. Solve the current cumbersome offline process and work mode of college sports teams, collect all data online, improve the overall control and data accumulation, improve the quality of reserve of college sports teams, and consolidate the foundation of sports reserve talents.
Lightweight Design of Honda Energy-Saving Racing Single-Shell Body based on Carbon Fiber Material
Authors: Li Jixiong , Wang Daoyong , Tian Ying , Pan Hanque
Published: September 2020

In order to obtain a lightweight Honda energy-saving race car body, the carbon fiber materials and monocoque technology were introduced into the design of the car body. Firstly, a lightweight structural monocoque body geometric model was constructed. Then the design geometric model was subjected to static strength, and the performance simulation analysis of the front collision condition and the rollover condition showed that the designed monocoque body can meet the requirements. Finally, the monocoque body model was processed and manufactured, which was assembled and integrated on the car for physics. The experiment results showed that the designed lightweight body meet the requirements of work performance.
Lightweight and Energy-Efficient Implementation of an Unclonable WSN Nodes on PSoC
Authors: Xue Ke , Chen Mengxian , Xu Rui , Zhang Ziqian , Cai Yiting , Ma Feng
Published: September 2020

An adversary can easily capture a wireless sensor network (WSN) node and extract the security information stored in the node, including keys, shared secrets and so on. Due the resources limitation, the traditional encryption and authentication protocols are impractical on WSN nodes. In this letter, we proposed a lightweight and energy-efficient anti-clone design for the WSN nodes, in which physical unclonable function (PUF) is adopted to enhance the security of the WSN nodes. The new structure aims at achieving a low cost and low energy method to prevent the node to be captured and cloned by the adversary. Unclonable WSN nodes are implemented on cypress PSOC 4, in which a configurable PUF structure is accomplished by use the universal digital block. Experimental results show that the proposed system can prevent the capture and clone attack in wireless sensor network, which is unavailable in previous WSN nodes.
Placement of the Assist Stop Areas in High-Speed Maglev System Considering Bidirectional Operation
Authors: Tian Yi , Geng Shuheng , Wang Yunfei , Xue Jiankang , Chen Lei
Published: September 2020

The location of the assist stop area in high-speed maglev system is closely related to the operation and maintenance of high-speed maglev train, which is the basic condition for continuous train operation. In this paper, a high-speed maglev assist parking area location setting method considering two-way operation is established. The method calculates the positions of assist stop area in both directions, and optimises the spacing and quantity to obtain the optimal placement of assist stop areas with the minimum quantity.
A Highly Portable Solution for MWD Data Remote Transmission
Authors: Ma Chaoqun
Published: September 2020

The remote transmission of drilling information is the development trend of modern drilling wells. However, due to historical reasons, the early MWD in China generally did not have the remote transmission function, or did not support the standard WITS protocol remote transmission function. Because of the number of such MWDs is large, the price of MWD is expensive, and the stability of the performance, ease of maintenance of MWD, now MWD is still in large use, so it is necessary to develop MWD remote transmission functions in order to make full use of these large amounts of MWD resources. However, because there are so many different domestic MWD brand models, and their decoding software is also different, and some of the early software development did not consider the remote design, so how to find a general and simple solution, to achieve the MWD remote transmission function, in order to make full use of MWD resources, has a realistic significance.

After carefully studying the existing various MWD data characteristics, this paper designs a common WITS remote transmission solution for the data storage structure of MWD, which is based on the data storage structure of MWD, and the storage mechanism. With this solution, the innovative data from the database is read and converted to the WITS format, using the TCP/IP protocol and the Serial Port protocol to send. Because this scheme reads data directly from the database file, it avoids communication restrictions with The MWD software and has a strong portability.

Using this solution, The WITS function was developed for HL-MWD and tested in the actual drilling. The results show that the solution is stable and feasible, portability is strong, has universal reference significance for other similar MWDs, and can be developed quickly on the basis of this solution for other MWDs.
Development of Urban Space Based on Student Migrants in Bandung City, Indonesia
Authors: Permana A Y , Akbardin J , Nurrahman H
Published: September 2020

Transformation is a total transition process from a form into a new figure which can be interpreted as the final stage of a process where space and time become greatly affect the changes to the ultimate stage. Changes are done by giving the response of the influence of external and internal elements that will lead to a change of shape that has been known previously. The title of “education city” to the city of Bandung past of history of its establishment. Education in Bandung began to show its development since the establishment of Hollandsch Inlandsche Kweekschool, shortened into HIK48, on May 13, 1868. It was established by some important figures, among others, were R. H. Muhammad Musa. Meanwhile, higher education began to grow since the establishment of Technische Hoogeschool (abbreviated as THS) in 1920 as part of the Ethical Policy of the Dutch Government to its colony. So since then, the life of higher education in the city of Bandung continues to grow and increase. THS is a forerunner to the birth of Bandung Institute of Technology (ITB now). The purpose of this study is to establish the theory that can explain how the transformation of urban space in Balubur Tamansari in Bandung City, so it can be seen adjusting the physical setting of the region as the city’s identity. The research method used was a qualitative grounded theory research method, the approach is focused on the discrete phenomenon in the field in order to disclose the meaning of the background of the city region space. This phenomenon was appointed through a process of snowball sampling. The process of data collection, analysis and theory building will be done at the same time in a period of time and iterative of process. This research generates knowledge building based on the knitting of the value system, the activity of perpetrator and physical setting in the region.
Improvement of Expansive Soils Stabilized with Rice Husk Ash (RHA)
Authors: Daryati  , Ramadhan M A
Published: September 2020

This study aims to stabilize expansive soil with RHA by 0%, 3%, 6% and 9%. The index properties test with existing soil included lean clay (CL). The existing soil was repaired by adding stabilizing material in the form of RHA as an added material. Based on the specific gravity test, it can be concluded that the addition of RHA reduced the value of specific gravity, made the plastic limit (PL), liquid limit (LL) and plasticity index (IP) decrease, which means that it could improve the properties of the existing physical soil. Standard Proctor Compaction Test (SPCT) with unsoaked method was conducted by giving 3 different number of blows, i.e. 10, 25, and 56 blows in 3 layers. The results show that the optimum moisture content (OMC) was almost constant, while the maximum dry density (MDD) slightly increased and most were added to an additional 6% of RHA. CBR test results show that the existing soil was 0.053 and after adding RHA, increased to 130% in the addition of 6% of RHA.
The Local Aggregates Performance’s Test Against Severe Environment on Different Quarry
Authors: Pramudiyanto  , Ma’arif F
Published: September 2020

A concrete structure reinforced with reinforcing bars formed an important part on current infrastructures. The high compressive strength of concrete combined with a high tensile strength of steel give an ideal composite material which offer a wide range of application within civil engineering structures. The aim of this research is to observe the corrosion process on reinforcing bars of reinforced concrete structure which is made by local aggregates which have the compressive strength ranged from 25 to 30 MPa, with different quarry in the area of Special Region of Yogyakarta. The ASTM G-109 and Florida Test of Method FM 5-522 are chosen to conduct this research. The test was conducted 45 to 60 days with following data to be taken: water salinity (pH), voltage reading relative difference, reinforcing bar’s mass loss. The data processed to obtain corrosion current density (CCD) and corrosion rate (CR). The results as follow : (1) the voltage difference’s reading on each specimens attempt to be similar, (2) the CCD on each specimens behave differently with relative differences of 1,68%, (3) the CR on each specimens behave differently with relative differences of 0,66%, (3) the specimens behave similarly regardless the differences between two of them.
Reliability-based Design Optimization for Structures Using Particle Swarm Optimization
Authors: Gaby G , Prayogo D , Wijaya B H , Wong F T , Tjandra D
Published: September 2020

Studies on structure design optimization have been conducted extensively over the past decades because it can increase structural efficiency and maximize the engineers’ profit. One of the significant current discussions is the reliability aspect of structure design in addition to optimal design. This problem becomes more important especially in sizing and shaping optimization of truss structures. To address the problem, this paper applies Reliability-based Design Optimization (RBDO) by combining Latin Hypercube Sampling (LHS) and metaheuristic algorithms which are Particle Swarm Optimization (PSO) and Barebone PSO (BBPSO). The presence of uncertainty is modeled using LHS and the reliability constraint is added to measure the probability of structural failure. This study aims to investigate the performance of these metaheuristic algorithms in optimizing the structure design while still satisfying the reliability constraints. Two case studies, a welded beam design problem and 15-bar planar truss problem, are used in this study. The performance of these two algorithms will be compared. The obtained results indicate that BBPSO has a better performance than PSO.
Study of Utilizations of Recycled LDPE Plastic and Stone Ash Waste from Remaining Split Stone Fragments for Block Paving Application
Authors: Arnandha Y , Rakhmawati A , Ali H H
Published: September 2020

Several waste materials have been continuously investigated for possible use as substitutes for materials in the field of civil engineering; one of them is plastic waste, due to the fact that plastic waste is simultaneously increasing. In this study, the block paving was made from recycled plastic bag (LDPE) with the addition of stone ash from stone crusher process waste for the value of 0%; 2.5%, 5%, 7.5%, and 10%. These additions of stone ash were intended in order to increase water absorption and increase surface roughness. Several physical and mechanical tests were carried out according to SNI-03-0691-1996. From the compressive test, the highest compressive strength is 13.43 MPa. Based on the results of the sodium sulphate resistance test and the external appearance tests, it showed that all block paving was in good condition with solid surface. In accordance toSNI-03-0691-1996, the paving block was included in the class-C quality which can be used for pedestrians.
Prediction of Concrete Properties Using Ensemble Machine Learning Methods
Authors: Prayogo D , Santoso D I , Wijaya D , Gunawan T , Widjaja J A
Published: September 2020

One of the most commonly used materials in civil engineering is concrete; not only is it cheap and strong, but it is also efficient and convenient. The efficiency of concrete is based on the easiness to place and to compact, which is usually known as workability. However, concrete strength and workability works in different ways; hence it is important to divide concrete into two groups: concrete with low workability and concrete with high workability, in order to achieve a more accurate prediction. Since there is a lot of variations of concrete mix designs, the relationship between each mixture is complex and, thus, requires advanced prediction methods in order to find the most accurate relationships between concrete mix proportion and its compression test result.–Recently, many studies have been conducted on applying multiple artificial intelligence (AI) methods in building different complex and challenging prediction models. Thus, this research employs ensemble machine learning methods to precisely forecast compression strength of concrete mix proportion. The accuracy of the proposed method was calculated using two performance measurements. Subsequently, the study has successfully built the prediction model that can accurately map the relationship between concrete mix proportion and compressive strength.
Bamboo Reinforcement Concrete Beam as Innovation for Low-cost Earthquake Resistant House
Authors: Hidayat N , Aldo A
Published: September 2020

The aim of study is to know about shape, specification, strength, and reduction bamboo reinforced concrete cost construction percentage against reinforced concrete. This study was conducted with a comparative quantitative method. The comparison examined includes cost reduction that occur when using bamboo. Study was using one of bamboo species called Bambusa Vulgaris which has great growth potential in Tidore City, especially Rum District. Bambusa Vulgaris is a strong and recommended bamboo for application as a construction material. Based on the analysis results, bamboo reinforced concrete has enough strength to replace the type of steel-reinforced concrete construction on sloof beam and ring beam. The use of bamboo as reinforced concrete for simple houses projects could save projects cost up to 10.4 million rupiahs. It reflects that Rum Village and Tidore City has tremendous bamboo potential to be used as a structural material. That fact expected that the results of this study can be empirically tested in the laboratory to determine mechanical properties of bamboo reinforced beams originating from Tidore City. For the long term, it is hoped that the local government can move together with the society of the Tidore City to cultivate bamboo seriously and sustainably.
Sediment Transport Modeling at Jelitik Estuary, Sungailiat - Bangka Regency for the Design of Sediment Control Structures
Authors: Wibowo M , Hendriyono W , Rahman R A , Susatijo G , Kongko W , Istiyanto D C , Widagdo A B , Nugroho S , Khoirunnisa H , Wiguna E , Aziz H , Santoso B
Published: September 2020

Since 2014 sedimentation at the estuary of Jelitik river, Sungailiat, Bangka has continued to increase. At this estuary, the ship traffic is very busy and there is National Fisheries Port Sungailiat. When the tide is low, the river mouth closes thus disrupting ship traffic. The Bangka Belitung Provincial Government is currently planning to build a sediment control infrastructure to reduce the sedimentation rate. To plan and determine the effectiveness of the jetties requires knowledge of sedimentation patterns around Jelitik estuary. Therefore this study was conducted to determine the pattern of sedimentation (distribution and rate) at the existing and ultimate conditions. The methods are field survey, analysis of field data, and computational modeling of sediment transport. Modeling of sediment transport was done using the Sand Transport Module of MIKE 21. Two scenarios were simulated for the existing and ultimate conditions. Based on this modeling, the sedimentation rate at Jelitik estuary is found uneven. In the existing condition, a large rate of sedimentation occurs on the southern side of the Jelitik River estuary, which reaches a maximum value of 2.75 m/year, with an average of 4.44 cm/year. Whereas in the ultimate condition, the sedimentation rate decreases to 0.0377 m/year.
The Tsunami Model of Mount Anak Krakatau Landslide in 2018 and Its Future Potential Hazard to the Coastal Infrastructures in Sunda Strait
Authors: Kongko W , Karima S , Daryono
Published: September 2020

This study is motivated by the tsunami event caused by Mount Anak Krakatau flank collapse on 22nd December 2018 which affected vital areas in Southern Sumatera and Western Java. A tsunami simulation will be carried out by using a 2D Non-Linear Shallow Water Equation Model to estimate the volume of the initial source as well as their tsunami mode at shores. Various scenarios of initial water volume replicating the tsunami source were applied, where the tsunami heights and their periods reach shores are validated with mareogram data at four Stations. The fact that the remaining materials of Mount Anak Krakatau after the 2018 event are still potential to generate a hazardous tsunami in the future and threaten the coastal infrastructures along the coastal Sunda Strait area. In this study, the validated parameters resulting from the 2018 event above are applied to model of the plausible worst scenario where the entire of the flank of Mount Anak Krakatau potentially collapses in the future. The study is important to estimate the tsunami hazard potential in the future that obviously influencing major activities and life’s in vital industrial-urban area in Southern Sumatera and Western Java.
Sustainable Design for Passage Boat Ports in Remote Areas in Era Construction 4.0 at Sidoarjo East Java Indonesia
Authors: Hermawan S , Harsono K , Bong N
Published: September 2020

Humans activities can not separate from transportation. In the remote area, one of the favourite types of conventional water transportation was Passage Boat. However, this transportation less pays attention to the safety factor and the facility. The research location in Jabon Subdistrict, Sidoarjo, where many people identified falling into the river in 2019. To reduce the number of accidents, it requires to design and hydrodynamic data at the location. However, the data are too expensive. The goal of this research is to utilise economic devices measurement based on the industrial revolution 4.0 with hydrodynamic methods models in the field of civil engineering and to make a sustainable design for passage boat ports. The methodology in this research initially does measurement nearshore bathymetry data. Then, the numerical hydrodynamic model is carried out for an approach to estimate the hydrodynamics of coastal waters, including tides, currents and water levels using the open-source Delft3D software. The outcomes of this study prove that hydrodynamic modelling can use to determine the height of the water level at maximum tides and low tides and to determine the current velocity to create a suitable passage boat ports design that is safe for the community and environmentally friendly.
The Influence of the Physicochemical Parameters on the Ortho Phosphate and Total Phosphate Concentrations of Maninjau Lake
Authors: Komala P S , Primasari B , Ayunin Q
Published: September 2020

The study was conducted in order to examine the relationship between the physicochemical parameters (temperature, DO and pH) with the orthophosphate (OP) and total phosphate (TP) concentrations based on the depth of Maninjau Lake. Samples were taken at the center of the lake near to a domestic area, endemic fisheries and a hydropower site. The OP concentration ranged from 0.182 - 0.570 mg/L and the TP of 0.265 - 0.603 mg/L indicated that Maninjau Lake was hypertrophic. This does not meet the quality standards regulated by the Indonesian Government. The physicochemical parameters of temperature, pH, and DO have a strong negative correlation with OP and TP concentrations with a correlation value of 0.828-0.982. ANOVA showed that depth stratification affects the OP and TP concentrations while the variation of sampling time does not affect the concentrations. The highest total phosphate concentration value was at the aquaculture cage location which exceeded the second class quality standard based on Government Regulation No. 82 of 2001. It shows that the aquaculture activities result in excess phosphate loads that can trigger lake eutrophication.
The Effect of Crib Installation with Placement Variations in River Bends Using Laboratory Model Tests
Authors: Wibowo D E , Purwantoro D , Pradipta D A
Published: September 2020

Scour or landslide is a problem that occurs at river bends. Many methods are used for scouring or landslide protection. One of the protections for scouring construction is crib model by using gabions and current-aligning bamboo. The purpose of this study is to determine of the effect of variations in the placement of the crib by using of gabions model and the current-aligning bamboo on the river bends. This research is an experimental test of the hydraulic model using river flume model with 5m on bend length, 0.8m width, 0.5m height and a constant discharge of 7.07lt/sec. The test consists of testing control, that is a bend without reinforcement and testing with reinforcement at the bends. The reinforcement at the bends using placement variation was twice carried out with the variation 1 consisted of 3 current-aligning bamboo, 4 gabions, 3 current-aligning bamboo and the variation 2 contains the opposite. The test results showed that the maximum scouring occurs in variation 1 with -5.4cm, -5.2cm on landslides and 0.61cm on scour. The results of the Surfer App and cross sections of stations P00 until P07 are more effective using gabions, while P08 through P24 are more effective using current-aligning bamboo.
Leadership, Cultural Values and Motivation on Employees Performance about Green Hospital
Authors: Susanto A J , Nopiyanti E
Published: September 2020

The Hospital’s often lose their image because of poor services and poor management. The employee’s performance about green hospital is based on responses to environmental problems for hospitals, such as management’s actions in the process of using natural resources efficiently and effectively. Some variables that are expected to influence employee’s performance about green hospital are leadership, cultural values, and motivation. The purpose of the study was to obtain information and find out the direct effects of leadership, cultural values, and motivation on employee’s performance about green hospital. The research is associative causal using a quantitative approach and applying a path analysis. The results show that there is a positive direct effect of leadership, cultural values and motivation on employee’s performance about green hospital. It can be concluded that employee’s performance about green hospital is influenced by leadership, cultural values, and motivation.
The role of location and social impacts of protected areas on subjective wellbeing
Authors: Jones Nikoleta , Malesios Chrisovalantis , Kantartzis Apostolos , Dimitrakopoulos Panayiotis G
Published: September 2020

Beneficial impacts on wellbeing levels of communities living near Protected Areas (PAs) is a key factor for meeting biodiversity conservation targets. Recent studies suggest that the proximity of communities to a PA influence to a significant extent their wellbeing levels. This paper explores further this argument by analysing data from approximately 800 respondents living inside or near four PAs of international importance in Greece. A Bayesian regression modelling approach testing which factors influence subjective wellbeing was applied. While wellbeing is explained by a combination of factors, the results of the study reveal that it is mainly PAs’ social impacts that have an effect on subjective wellbeing levels followed by the geographical location. This finding suggests that more effort needs to be invested in the equal distribution of PAs benefits in order to increase wellbeing and public support for these areas.
Composition and Characterization of Actinomycetes Isolated from Nipah Mangrove Sediment, Gastrointestinal and Fecal Pellets of Nipah Worm (Namalycastis Rhodhocorde)
Authors: Yanti A H , Setyawati T R , Kurniatuhadi R
Published: September 2020

Nipah worm (Namalycastis rhodochorde) belongs to the Polychaeta group that lived in the Nypa fruticans mangrove sediment in West Kalimantan. It has the potential to be cultivated because it has a high economic value in aquaculture. Feed aspect is an essential part of its cultivation, through improving the quality of feed by using probiotics isolated from its natural habitat, such as actinomycetes. These bacteria are known capable of producing secondary and primary metabolites. These metabolites are expected to increase immunity and biomass of worms. The purpose of this study was to isolate and determine the composition and characteristics of actinomycetes derived from mangrove sediment, gastrointestinal and faecal pellets of nipah worm that are potential as probiotic for feed formulation. Isolation and characterization of actinomycetes was conducted by pour plate method on SCA, ISP2, ISP3, ISP4, and ISP5 media; while characterization was by determining morphological characteristics of colonies, cell structure, and biochemical tests. Identification of the isolates referred to Bergey’s Manual of Determinative Bacteriology. The results showed that twelve isolates of actinomycetes had been found. Six isolates were from mangrove substrate, four isolates from fecal pellets and two isolates from the gastrointestinal tracts. All isolates were closely related to the genus Streptomyces.
Bioaccumulation of Heavy Metal in Avicennia sp. from Blanakan Riparian, Subang, West Java
Authors: Ayujawi S A , Takarina N D
Published: September 2020

The heavy metals from an aquatic environment can be absorbed, transported, and stored in mangrove tissues. This study aims to assess accumulations of Cu and Zn in the sediment, root, and stem ofAvicenniasp. as affected by human activity in Blanakan riparian, West Java.Avicenniasp. root, stem, water, and sediment samples were collected from 2 stations located in Blanakan riparian. The concentrations of Cu and Zn in samples were measured using an atomic absorption spectrophotometer (AAS). Bioconcentration factor (BCF) and translocation factor (TF) equations were used to analyse the Cu and Zn accumulations inAvicenniasp. Based on the sediment quality guidelines, the sediment samples were not polluted for Cu (2.23–2.26 mg/kg) and moderately polluted for Zn (92.83–95.86 mg/kg). Moreover, the Cu and Zn in the water have BCF values of root ranging from 257.5–295 and 97.07–390.29, while BCF values of stem ranging between 590–990 and 90.23–330.21, respectively. Furthermore, the Cu and Zn in the sediment have BCF values of root ranging from 0.23–0.26 and 0.30–0.57, while BCF values of stem ranging between 0.53–0.88 and 0.30–0.48, respectively. In addition, the TF values ranged from 2.29–3.36 for Cu and 0.85–0.93 for Zn. To summarize, the root and stem ofAvicenniasp. have the ability to translocate Cu from water and sediment in Blanakan riparian.
Estimation of Carbon Stocks in Mangrove Stands at Bagek Kembar Mangrove Ecotourism Sekotong West Lombok
Authors: Candri D A , Athifah  , Farista B , Virgota A , Rohyani I S , Ahyadi H
Published: September 2020

The Bagek Kembar mangrove ecotourism area, Sekotong, West Lombok has been designated as one of the mangrove essential ecosystem areas in West Nusa Tenggara. One of the ecological services of a mangrove ecosystem is carbon storage. Mangrove forests can store carbon four times higher than the world’s tropical rainforest. This study aimed to assess the amount of carbon stored in mangrove stands in the Bagek Kembar mangrove ecotourism area, Sekotong West Lombok. This study uses a random sampling method, which is the placement of random plots in each mangrove zoning. The mangrove zoning is divided based on the distance from the sea and the river starting from 50 meters, 100 meters, 150 meters, 200 meters, 250 meters, and 300 meters. In addition, the mangrove area was divided into two mangrove statuses, which are natural mangrove succession and rehabilitation, and 10% of the 5x5 meter observation plot sample was taken. So that there were 286 observation plots obtained. Calculation of mangrove biomass using allometric equations. The results of the estimation study of carbon deposits on mangrove stand biomass in the Bagek Kembar Mangrove Ecotourism area of a average of 6 zonings amounted to 10,738.49 kg/ha2.