bluuebunny/crossref_metadata_2025 huggingface dataset:
Bearing fault diagnosis by combining a deep residual shrinkage network and bidirectional LSTM
Authors: Tong Yizhi , Wu Ping , He Jiajun , Zhang Xujie , Zhao Xinlong
Published: November 2021

Bearings are indispensable and key components in rotating machinery. To ensure the safe and reliable operation of rotating machinery, bearing fault diagnosis plays a crucial role. To explore the spatial and temporal information in vibration signals, a novel bearing fault diagnosis method is proposed by combining a deep residual shrinkage network (DRSN) and bidirectional long short-term memory (Bi-LSTM) network in this study. Firstly, a DRSN is employed to extract the spatial features from noise-related vibration signals. Then, a Bi-LSTM network is adopted to further address the long-term dependencies problem in vibration signals, where the temporal information is exploited. By integrating DRSN and Bi-LSTM, the spatial and temporal information of vibration signals is fully extracted. Finally, a fully connected layer with Softmax is used to offer the diagnostic results. Experimental results using two case studies demonstrate the effectiveness of the proposed method by comparison with other state-of-the-art methods.
New refined analytical models for various bonding conditions of an adhesively bonded smart PZT transducer using the EMI technique
Authors: Parpe Aditya , Saravanan T Jothi
Published: November 2021

The electro-mechanical impedance (EMI) technique has emerged as a cost-effective and non-destructive technique to detect the possible damages in the structure using a piezoelectric transducer, especially, lead zirconate titanate (PZT). The adhesive bond layer plays an important role in the PZT patch-host structure interaction for monitoring structural damage. Two bonding conditions are investigated in this research paper. Primarily, the debonding phenomenon of the adhesive bond layer may misinterpret the EMI response on the damage caused in structure. Subsequently, the investigation included the protective layer at the top of the PZT transducer to avoid sensor degradation. However, the analytical models developed so far have not considered a protective layer at the top of the PZT transducer. This paper presents the novel two-dimensional (2D) analytical model for incorporating debonding concepts and the new refined 2D analytical model to include a protective layer in the study of surface-bonded PZT transducers. The proposed analytical models are verified with the experimental studies. The experimental and analytical results show good agreement, which confirms the effectiveness of the new models. This paper also incorporated the effect of each bonding condition for monitoring structural damage by implementing the EMI technique. For the simulation, the numerical investigations on the PZT transducer bonded on the metallic (aluminum and steel) and concrete blocks are performed using coupled field analysis through finite element (FE) modeling. It is found that each bonding condition has influenced the resulting signatures. The signatures obtained from developed theoretical models and numerical simulations using three-dimensional FE models for each bonding condition are compared to highlight the influence on structural damage detection. The trend of signatures is found to be matching satisfactory. Several parametric studies have been conducted to show the efficacy of the new refined model with a protective layer. It considers the different input properties of an adhesive layer, host structure, and temperature conditions. The influence of debonding of the protective layer is also studied, and the obtained results support the need for a protective layer in the models.
Electromechanical feedback control of nanoscale superflow
Authors: Varga E , Davis J P
Published: November 2021

Superfluid 4He is a promising material for optomechanical and electromechanical applications due to its low acoustic loss. Some of the more intriguing aspects of superfluidity—the macroscopic coherence, topological nature of vorticity, and capability of supporting non-classical flows—remain, however, poorly explored resources in opto- and electro-mechanical systems. Here, we present an electromechanical coupling to pure superflow inside a nanofluidic Helmholtz resonator with viscously clamped normal fluid. The system is capable of simultaneous measurement of displacement and velocity of the Helmholtz mechanical mode weakly driven by incoherent environmental noise. Additionally, we implement feedback capable of inducing self-oscillation of the non-classical acoustic mode, damping the motion below the ambient level, and tuning of the mode frequency.
North Celestial Region Observed with 21 CentiMeter Array
Authors: Zhao Bi-Xuan , Zheng Qian , Shan Huan-Yuan , Guo Quan , Li Kuan-Jun
Published: November 2021

The 21 CentiMeter Array (21CMA) is a radio interferometer in western China. The key science objective of 21CMA is statistically measuring the redshifted H i 21 cm signal of the Epoch of Reionization (EoR). In order to achieve this, a catalog of radio sources is necessary for both calibration and foreground removal. In this work, we present a catalog of 832 radio sources within a radius of 5° around the North Celestial Pole region observed with 21CMA. Three days of data taken in 2013 are used in the analysis, with a frequency coverage from 75 to 200 MHz and an angular resolution of about two arcminutes at 200 MHz. Flux densities and estimated spectral indices of the radio sources are provided in the source catalog. For simplicity, only the east–west baseline is used for the observations to avoid the so-called w − term in the data analysis. The longest baseline along the east–west direction is 2780 m. Comparing our source counts with other radio observations, we find a good agreement with the observations made with the Giant Metrewave Radio Telescope and Murchison Widefield Array. Our data reduction is still limited by grating lobes of very bright sources in the field due to the redundant configuration of 21CMA. We note that understanding the properties of radio sources, and modeling and removing the radio sources are challenges for the EoR experiments.
Specifics of using multifrequency pumping to register CPT resonances
Authors: Savinov K N , Dmitriev A K , Krivetskii A V
Published: November 2021

When pumped by a diode laser, the injection current of which is modulated simultaneously by microwave and HF signals, CPT resonances are recorded in absorption, spaced from each other by an amount equal to half of the HF modulation frequency.
Method for stabilization of the microwave modulation index in order to suppress the light shift of the coherent population trapping resonances
Authors: Yudin V I , Yu Basalaev M , Taichenachev A V , Radnatarov D A , Andryushkov V A , Kobtsev S M
Published: November 2021

For the resonance of coherent population trapping (CPT), we show that in the case of a spatially inhomogeneous light shift (for example, due to the Gaussian transversal profile of the light beam intensity), the zero position of the error signal, formed by the use of phase-jump technique, depends on the integration time of the spectroscopic signal. Basing on this effect, we propose two-loop method to stabilize the microwave power at the point where the light shift vanishes.
Light shifts in the rubidium CPT atomic clock with laser current modulation at 3.4 and 6.8 GHz
Authors: Ignatovich S M , Mesenzova I S , Skvortsov M N , Kvashnin N L , Vishnyakov V I
Published: November 2021

In the paper presents results of an experimental comparison of the CPT parameters of the resonance at the D1 line in 87Rb when the laser current is modulated at frequencies 3.4 GHz and 6.8 GHz. Resonances are investigated for slope to noise ratio (Q-factor) and shifts from the microwave power. The reproducibility of the parameters of VCSEL lasers required to obtain long-term stability of an atomic clock is considered. The obtained CPT instabilities of the atomic clock for 1 second were 1.2·10−11 for the case of 3.4 GHz and 4·10−12 for 6.8 GHz.
Detection of THz waves in GaSe:S crystals by femtosecond laser radiation with a telecom wavelength of 1.55 μm
Authors: Shevchenko O N , Nikolaev N A , Kokh K A
Published: November 2021

In this work, we study Ga50%Se50-x%Sx crystals (where x = 0, 1.5, 6, 8, 11) as an electrooptic detector of terahertz pulses using probing femtosecond laser radiation with the wavelength of 1.55 μm. It was found that the sample with x = 6 provides the highest detection efficiency. The efficient value of the electrooptic coefficient of GaSe:S crystals is estimated to be about twice higher than those of GaAs in the same conditions.
Controlling the type and intensity of low-frequency waves generated by laser plasma clots in a force tube of magnetized plasma
Authors: Berezutsky A G , Tishchenko V N , Chibranov A A , Miroshnichenko I B , Zakharov Yu P , Shaikhislamov I F
Published: November 2021

In this work, we study the influence of the parameters of a magnetized background plasma on the intensity of whistler waves generated by periodic laser plasma bunches in a magnetic field tube. It is shown that at 0.3 < Lpi> 0.4 Alfvén waves and whistlers are generated. In the region Lpi> 0.5, intense whistlers with an amplitude of δBmax/ B0∼ 0.24 are generated.
On the opportunity of Laser Plasma simulation of Plasma Jets formation in moderate magnetic fields ∼ kGs
Authors: Zakharov Yu P , Neznamov V P , Terekhin V A , Shaikhislamov I F , Posukh V G , Trushin P A , Chibranov A A , Berezutsky A G , Rumenskikh M S , Efimov M A
Published: November 2021

Today a number of various experiments with Laser-Produced Plasmas (LPP), done at very-high Magnetic Fields (up to B0
> MG) are using to model the physics of Astrophysical and Space Jets, a various processes of their formation and possible long-range propagation at various angles S to magnetic fields. We discuss the opportunity and present the first results of new-type experiments on simulation of Jets with LPP at KI-1 facility of ILP, at moderate magnetic field ∼ kGs, oriented quasi-transverse (S ≍ 600) of LPP-blob expansion (with velocity V
0) relative to B
0. They were done on the base of all our preliminary studies, both at large-scale, high-vacuum chamber (0120 cm of KI-1) and others devices with LPP (oriented earlier at V0 transverse to B0, with $ = 900).
Mathematical Modeling and Functional Order Pursuits with Separated Dynamics
Authors: Mamatov Mashrabjon , Alimov Xakimjon
Published: November 2021

This work is devoted to the study of the pursuit problem in controlled systems described by a fractional-order equation with divided dynamics. For fixed player controls, representations of solutions are established in the form of analogs of the Cauchy formula using generalized matrix functions. Sufficient conditions are obtained for the possibility of completing the pursuit. Specific types of fractional differential equations and models of fractional dynamical systems are considered. The qualitative dynamics, issues of stability and controllability of such systems are discussed. Considered, try which, the motion of the equation is described with irrational orders. Problems of the type under study are encountered in modeling the processes of economic growth and in problems of stabilizing dynamic systems.
Explicit Exact Solutions of Space-time Fractional Drinfel’d-Sokolov-Wilson Equations
Authors: Lin Hongkua
Published: November 2021

The space-time fractional Drinfel’d-Sokolov-Wilson equations (DSWEs) has attracted many researchers’ attention in recent years. In this study, combining the (G’/G,1/G)-expansion method and a fractional wave transformation, we derive abundant explicit exact solutions of the DSWEs with the conformable fractional derivative. All of the resulting solutions include triangle, hyperbolic and rational function type. It shows this technique is effective and reliable to find exact solutions of other similar nonlinear fractional partial differential equations (NFPDEs).
Numerical Simulation of Granular Column Collapse with Fractal Particle Size Distribution Using Discrete Element Method
Authors: Lai Zhiqiang , Pan Li , Wang Zhongmei , Wang Jiayi , Ren Yanfen
Published: November 2021

This study conducts numerical simulations of the granular column collapse with Fractal Particle Size Distributions (FPSDs) via the Discrete Element Method (DEM) and investigated kinetic behaviours of dry granular flows. The aim of this paper is to explore the effects of the fractal dimension of FPSD on the kinetics of dry granular flows. When the fractal dimension of the flows consisting of granular materials increases, the horizontal particle translational velocities become greater and the mobility improves, whereas the particle rotational velocities decrease. Meanwhile, the change in the potential energy increases, and the particle kinetic energy in the rotational form reduces; thus, the particle kinetic energy in the translational form increases. The reducing particle rotational movement may be related to the reducing particle shearing behaviours because only the contact shearing can affect particle rotational motion. In conclusion, a larger fractal dimension of FPSD of a dry granular flow leads to a longer spreading distance and a smaller rotational velocity.
An Echo Sequence Profile Image Based Ship Target Classification Algorithm for Low-Resolution Radar
Authors: Hang Duoduo , Zhang Ji , Chang Chuanwen , Zhu Wei , Wu Beibei , Zhang Hua , Wang Junbo
Published: November 2021

Ship target classification is of great significance in both military and civilian fields. We propose a ship target classification algorithm for low-resolution radars with echo sequence profile images. This algorithm can be realized in the following steps. First, we collect radar profile image data. We use five perspectives of a radar target, including target shape, Radar Cross Section (RCS), echo amplitude, motion attribute, and features of two-dimensional grayscale maps, to extract eight-dimensional feature vectors. The proposed algorithm uses the Support Vector Machine (SVM) as the classifier, and the parameters of the classifier are optimized by either grid search or the Particle Swarm Optimization (PSO) algorithm. The proposed algorithm is verified through real data classification tests.
Numerical Modeling of A New Virtual Trajectory Password Architecture
Authors: Chen Yuanyuan , Chen Jing , Li Mingzhu
Published: November 2021

With the development of digital technology, Computer technology, communication technology and multimedia technology gradually infiltrate into each other and become the main core of information technology. In information technology, digital, text, graphics, images, sound, video, animation and other information carriers are spread through computers and the Internet. Due to the openness, sharing, dynamic and other characteristics of the Internet, information security is threatened and interfered. Information security has become a strategic issue that people must pay attention to, which is related to social stability, economic development and national security. This paper studies a new kind of virtual track cryptography, which breaks through the traditional character memory method and transforms it into memory graphics by using mathematical modeling, and changes the surface memory method from memorizing numbers and characters to memorizing trajectory graphics, so as to make the traditional process of people memorizing passwords easier.
Weapon-Target Assignment Problem Using Modified Water Wave Optimization Algorithm
Authors: Wei Yuanfei , Luo Qifang , Zhou Yongquan
Published: November 2021

The weapon-target assignment (WTA) is a classic problem. The WTA mathematical model is that warship formations are reasonably equipped with weapons resources for each weapon system to attack the air threaten targets. The purpose of targets optimization is to maximize combat effectiveness, that is to say, the mathematical expectation is maximum. We adopt the greedy strategy and improved propagation operation is to strengthen the water wave optimization (WWO) search performance. This article elaborates a modified water wave optimization (MWWO) to solve the WTA problem, which can detect optimized allocation decision matrix and search for the maximum mathematical expectation. Based on parameter optimization, the overall performance of the MWWO is more stable, the search speed is accelerated and the accuracy is improved. The experiment results indicate that the MWWO are verified and avoids local optimum, and can be more convenient for solving the WTA and obtain better performance.
Spinneret Image Region of Interest Segmentation Algorithm
Authors: Li Dejun , Zhou Guiyang , Cheng Kang , Wang Cheng , Wang Yifan , Li Guanglong
Published: November 2021

In order to improve the accuracy of spinneret defect detection, a spinneret image region of interest segmentation algorithm is proposed for the problem that the complex background of spinneret image interferes seriously with the subsequent detection. The mask image is obtained by separating the fixed plate area and the spinneret wall area using the diffuse water filling method, and the minimum external circle and the maximum internal circle in the mask image are found using contour detection to obtain the mask image of the spinneret area, and then the spinneret area, i.e. the Region of Interest (ROI), is extracted. The experimental results show that this method can effectively separate the spinneret region and reduce the background interference.
Abnormal Detection to Big Data Using Deep Neural Networks
Authors: Zheng Jian , Li Zhaoni , Li Jiang , Liu Hongling
Published: November 2021

It is difficult to detect the anomalies in big data using traditional methods due to big data has the characteristics of mass and disorder. For the common methods, they divide big data into several small samples, then analyze these divided small samples. However, this manner increases the complexity of segmentation algorithms, moreover, it is difficult to control the risk of data segmentation. To address this, here proposes a neural network approch based on Vapnik risk model. Firstly, the sample data is randomly divided into small data blocks. Then, a neural network learns these divided small sample data blocks. To reduce the risks in the process of data segmentation, the Vapnik risk model is used to supervise data segmentation. Finally, the proposed method is verify on the historical electricity price data of Mountain View, California. The results show that our method is effectiveness.
Dynamic Performance Simulation Analysis of Electric Forklift Truck Based on ADVISOR
Authors: Zhang Li
Published: November 2021

According to the power system selection and technical parameters of the lithium titanate electric forklift that have been matched, the ADVISOR simulation software modeled the parameters of the drive motor, lithium titanate battery, reducer and other major components of the system. The acceleration ability, climbing ability and energy consumption of lithium titanate-electric forklift are simulated, and its technical parameters are obtained, which provides a basis for testing the rationality of system parameter matching.
Design and Simulated Analysis of Low Heat Flux Cold Plate for High-power Power Electronics Equipment
Authors: He Xunan , Kang YuanLi , Li Peng
Published: November 2021

The thesis has carried out design and simulated analysis of low flux cold plate for high-power power electronics equipment. First, according to heat distribution and design requirements, two kinds of flow passage for low flux cold plate is designed. Then performance characteristics simulation of different flow passage for cold plate is performed. And the heat dissipation characteristics of two kinds of flow passage can both meet the design requirements. Finally, from the perspective of high temperature, temperature difference, pressure drop and so on, the simulated results are comparative analysis. And it is helpful to the design and optimizing of cold plate for high-power power electronics equipment.
Engine Fault Detection Approach Based on Angle Domain Signal Model
Authors: Zeng Hai , Zeng Ning , Han Jin , Ding Yan
Published: November 2021

Engine vibration signals include strong noise and non-stationary signals. By the time domain signal processing approach, it is hard to extract the failure features of engine vibration signals, so it is hard to identify engine failures. For improving the success rate of engine failure detection, an engine angle domain vibration signal model is established and an engine fault detection approach based on the signal model is proposed. The angle domain signal model reveals the modulation feature of the engine angular signal. The engine fault diagnosis approach based on the angle domain signal model involves equal angle sampling and envelope analysis of engine vibration signals. The engine bench test verifies the effectiveness of the engine fault diagnosis approach based on the angle domain signal model. In addition, this approach indicates a new path of engine fault diagnosis and detection.
Modeling and Algorithm Research on Identification of Wrong Wiring Power Supply Region based on Classification Analysis
Authors: Li Zongpeng , Yu Liang , Liu Jian , Su Liangli , Tan Huang , Zhao Jiakui , Lin Xiaojing , Cheng Hui , Zhang Hao
Published: November 2021

The wrong wiring of the power supply region directly affects the accuracy of the metering data. This paper based on the existing data of the power supply regions, defined four indicators which include minimum negative line loss rate, maximum positive line loss rate, minimum power factor and maximum number of negative power values. Then by using the four indicators before and after the wrong wiring rectification of the historical wrong wiring regions and the decision tree algorithm, the wrong wiring regions identification model was built. The identification model was used to identify the wrong wiring regions in all regions of the power company, and the regions identified as wrong wiring by the model were inspected on-site. The inspection result shows that the precision of the model is satisfactory, which can effectively improve the inspection and rectification efficiency of the wrong wiring regions.
Verification Simulation and Development of New Marine Transport Model
Authors: Zhang Jing
Published: November 2021

The structure of the global supply chain creates an imbalance in trade between regions of the world. It creates many empty containers on the ocean shipping route. Focusing on this problem, we will develop an empty container relocation plan for empty containers in a marine container logistics network connecting multiple bases and propose a model that minimizes the total cost of container transportation. The proposed model was verified by the simulation designed and developed in this study, and the effectiveness of the proposed model was shown by the data of the marine transportation company.
Simulation and Research of Urban Intelligent Traffic Light Control System
Authors: Sun Chunling , Liu Fuhai
Published: November 2021

Intelligent traffic light control system belongs to the field of transportation public safety control. So far, the traffic light control system on the market cannot change the working time of the traffic lights according to the actual traffic flow, which is not conducive to the easing of the traffic flow and easy to cause traffic jams. Therefore, it is necessary to solve the problem of the existing traffic light control system which cannot adjust the working hours of the traffic light according to the actual road conditions, so as to alleviate the traffic jam at the intersection to a certain extent. In this paper, the design of intelligent traffic light control system uses AT89C51 MCU as the core device. The system controls the traffic of different times and different conditions, and it can alleviate traffic jam to a certain extent. This paper analyzes the hardware and software designes of intelligent traffic light control system, and simulates traffic light control by simulation software. The system of this paper is simple in structure, economical and practical, reliable in operation and it can effectively dredge the traffic.
Short-Term Wind Speed Forecasting Using Meta Learning-based Elman Neural Network
Authors: Madhiarasan M.
Published: November 2021

Adequate power provision to the customer and wind energy penetration into the electrical grid is necessitated for accurate wind speed forecasting in the short-term horizon to realize the scheduling, unit commitment, and control. According to the various meteorological parameters, the wind speed and energy production from wind energy are affected. Therefore, the author performs the multi-inputs associated Meta learning-based Elman Neural Network (MENN) forecasting model to overcome the uncertainty and generalization problem. The proposed forecasting approach applicability evaluated with real-time data concerning wind speed forecasting on a short-term time scale. Performance analysis reveals that the meta learning-based Elman neural network is robust and conscious than the existing methods, with a least mean square error of 0.0011.
Simulation of the Performance Metrics for Securing DSDV Routing Protocol Based on Trusted Environments
Authors: Feng Chiang Ling
Published: November 2021

To organize the network in an efficient way to minimize the risk of illegal node and to safeguard protected information, a security mechanism is required to secure communication. In addition, a security mechanism is also required to ensure that received information have not been tampered with. In this paper, a more efficient mechanism for Securing the Destination Sequenced Distance Vector Routing Protocol (SDSDV) is proposed. This paper comprehensively investigates the performance impacts by varying the number of maximum connections and mobility on securing the ad hoc network with Destination Sequenced Distance Vector Routing Protocol (DSDV) Routing Protocol. From simulation results, we explore the causes for performance degradation. Based on the investigation, we indicate that we have to impose restrictions on the maximum connections to acquire an expected performance. These results also reveal that the performance decreases with the increment of the mobility and maximum connections that is unequal to 60. If we want to obtain the optimal performance, the number of nodes in a network should be constrained to be 60 if the maximum connections are 60.
The molten wood’s metal initial velocity variations effect on breaching simulation by MPS method
Authors: Hidayati A N , Waris A , Mustari A P A , Irwanto D , Aprianti N A
Published: November 2021

Series of MPS simulations have been conducted using two-dimensional geometry. The simulation was based on Sudha’s experiment (2018) about initial velocity variations on molten Wood’s Metal (WM). The molten WM would be flowed through nozzle with the diameter was 6 mm. It would impinge to the Woods Metal Plate (WMP) which 270 mm below the nozzle. The WMP diameter was 470 mm. The temperature of molten WM and WMP were set at 573 K and 300 K, respectively. The initial velocity of molten WM was varied at 0.327 m/s, 0.397 m/s, 0.498 m/s in the y-negative direction. The simulation was calculated by using 2D MPS with additional procedures such as heat transfer calculation and defining a new type of wall particle. The results showed some different spread patterns, leading edge and phase fraction change for each initial velocity. It can be concluded that with varying the initial velocity will affect on the radial spread pattern but not so much effect occurs on the phase volume fraction change.
Mathematical modelling of soybean var. anjasmoro plant growth
Authors: Aditiawati P , Viridi S , Palupi S , Rostiani R , Samosir M D , Primaresti P D
Published: November 2021

Thorough understanding of interactions between all factors involved in soybean plant cultivation process is needed to increase the yield. This study is aimed to determine which interaction has the highest correlation according to the Pearson correlation coefficient, to define a certain model for said interaction, and to confirm the identicality of all samples that were observed using destructive sampling method. After being tested using Pearson correlation coefficient, the highest r value is 0,81 which is between plant height and number of leaves, proving they are highly related. Both parameters were simulated in several different ways until it was found that number of leaves variable is best described as function of plant height variable, the equation is y1 = 0,85x1 + c1 where y1 represents number of leaves and x1 represents plant height. Identicality between all plants is not confirmed, thus destructive sampling method is not recommended to be applied for similar studies.
Physical protection system effectiveness calculation in nuclear reactor facility using EASI code: case study sabotage scenario
Authors: Andiwijayakusuma D , Mardhi A , Asmoro T , Setiadipura T , Purqon A , Su’ud Z
Published: November 2021

Every nuclear facility must pay attention to the 3S aspect (Safety-Security-Safeguard) to prevent nuclear accidents. One element in the nuclear security aspects includes a reliable Physical Protection System (PPS), which aims to ward off security disturbances and other illegal acts, i.e., sabotage, theft, Etc. This study evaluates the PPS performance by adversary-path analysis approach using the EASI code for hypothetical nuclear reactor facility to anticipate sabotage attacks as the highest consequences scenario. We perform the probability of interruption (PI) calculation as represented by the effectiveness of the PPS. The study results show that in the PPS design, calculating the PI value using the EASI code confirms the need to pay attention in determining the MVP. The results provide feedback for the PPS designer to accept the current design or strengthen it to obtain a reliable PPS.
Preliminary Neutronic Analysis of 150 MWt High-Temperature Gas Reactor to Produced Electricity in Small Area
Authors: Yuningsih Nining , Irwanto Dwi
Published: November 2021

There are small areas in Indonesia with insufficient electricity. High-Temperature Gas Reactor (HTGR) is a promising nuclear power plant that can be used in such areas as its capability to produce electricity and co-generation applications. A preliminary study on the neutronic aspect of the 150 MWt HTGR design is performed in this research. High Temperature Engineering Test Reactor (HTTR) is used as a basic model. The calculation was performed by Standard Thermal Reactor Analysis Code (SRAC) code, and Japanese Evaluated Nuclear Data Library (JENDL) 4.0 as nuclear data library. As a result, by increasing HTTR fuel assembly geometry to 1.5 times its original and using higher uranium enrichment, the reactor can be operated for five years.
Neutronics performances of gas-cooled fast reactor for 300-600 MWt Output Power with Modified CANDLE burn-up scheme in radial direction
Authors: Irka F H , Suud Z , Irwanto D , Khotimah S N , Sekimoto H
Published: November 2021

Gas-Cooled Fast Reactor-GFR is a Generation IV reactor that is helium-cooled and has a closed fuel cycle. Due to the target operation on 2022-2030, this reactor type still needs further research and development technologies. We investigated the neutronics performances of a GFR balance type core with some modification of CANDLE (Constant Axial shape of Neutron flux, nuclide densities and power shape During Life of Energy production) burn-up scheme in the radial direction. The output power varied from 300 to 600 MWt. The neutronics calculation was performed using SRAC 2002 with JENDL 4.0 nuclear data library. The analysis indicate the reactor could operate critically for ten years without refueling with burn-up level 20% HM.
Comparative of blanket reactor design in assuring of tritium self-sufficiency
Authors: Maemunah I R , Su’ud Z , Waris A , Irwanto D , Yazid P I
Published: November 2021

The comparison of four blanket modules in DEMO made up the optimization material having a reasonable requirement as blanket material in this study. Either neutron flux distribution in blanket material or material endurance under neutron irradiation, from four modules, the WCLL has a high tolerance neutron distribution and the best neutron irradiation endurance. Furthermore, many suggestions closed to the statement to use the benefits of water coolant and lithium lead (compose Li-6) as a material component in the blanket.
Physical forces driving chlorophyll-a variability in the South Java Sea Shelf: a spatio-temporal analysis
Authors: Budiman A S , Bengen D G , Arifin Z , Nurjaya I W , Ismail M F A
Published: November 2021

The wind and current are two physical forces that strongly influence the biogeochemistry in coastal waters. Both of these forces could enhance the Chlorophyll-a (Chl-a) concentration through the upwelling process. Here we examine the contribution of the wind and current to the Chl-a variability in the South Java upwelling system in terms of wind stress and bottom stress respectively using satellite-derived and reanalysis data from 2002 to 2017. Ten longitudinally cells were used for further analysis. A long-term Chl-a shows a strong longitudinal gradient of Chl-a with the highest value on the shelf. Seasonal and Inter-annual Chl-a analysis shows the evidence of the monsoonal winds and other forcing effects relevant to the previous studies. Wind stress (τwx
) has a strong seasonal variation which is upwelling- favorable during southeast monsoon coincide with higher Chl-a suggesting wind as the main forces during that time, while bottom stress (τbx
) has more complicated variations, but it’s seen that τwx
mostly downwelling-favorable or eastward circulations. There were about 39.92- 52.94% of positive Chl anomalous events generated by the combination of upwelling- favourable τwx
and downwelling-favorable τbx
, higher than other combinations. In terms of Oceanographic drivers, the wind has a higher effect on enhancing Chl-a through a negative correlation. τwx
leads the Chl-a anomalies by about 15 – 24 days with a correlation coefficient of more than 0.6.
Surface currents modeling based on tidal cycles and monsoon in tropical estuary, Indonesia
Authors: Najamuddin  , Prartono T , Sanusi H S , Nurjaya I W , Pembonan R E , Umasangaji H , Mutmainnah  , Tahir I , Inayah
Published: November 2021

The modeling uses a software-based numerical model DHI MIKE user interface developed by The Danish Hydraulic Institute (DHI) Water and Environment, Denmark. Simulation of current uses a 2-dimensional model (averaging to depth) with a finite element approach. Modeling of currents was conducted to know current dynamics by tidal cycle and seasonal variation (west and east monsoon). The models were validated using correlation coefficient value (r) by comparing direct measurement and model output. The r-value for current velocity during west monsoon was 0.653 and east monsoon was 0.697 and for current direct during west monsoon was 0.887 and the east monsoon was 0.857. While the r-value for the tide was 0.858. All these r values showed a strong correlation and these indicated the models were valid. The result of the simulation of the current models showed that the surface currents were strongly influenced by the tidal cycles. The currents direct flowed to the south at flood tide and to the eastern at ebb tide. The maximum current velocity during the west monsoon was 0.50 m/sec and during the east monsoon was 0.40 m/sec. The averages of currents direct were more dominant eastward of Jeneberang estuary.
Distribution of some natural and anthropogenic radionuclides in the sediments and seawater along the coastal areas of North Sulawesi
Authors: Putra D I P , Prihatiningsih W R , Makmur M , Yahya M N , Priasetyono Y , Untara
Published: November 2021

Studies on the radionuclide distribution of some naturally occurring radioactive materials (NORM) and anthropogenic radionuclides in the sediments of the coastal areas of North Sulawesi were conducted to provide baseline data for the effective monitoring of radioactive fallout in these areas. Sediment samples were collected by a van Veen grab samples about 100 – 300 m from the shoreline, and 60 L of seawater was pre-concentration to precipitated 137Cs. Activity concentration of the three main natural radionuclides (222Ra, 232Th, and 40K) and 137Cs were determined using a high-resolution HPGe gamma-spectroscopy system and presenting background about the radiological levels and assessing the associated hazards. The activity of 226Ra ranged from 2.1 to 9.5 Bq kg−1 with an average value of 5.9 Bq kg−1. The activity of 232Th varies from 2.4 to 10.4 Bq kg−1 with an average value of 5.2 Bq kg−1. The 40K ranges between 169.1 to 492.7 Bq kg−1 with an average value of 238.8 Bq kg−1. The average activity concentration of 40K (238.8 Bq kg−1) in the sediment samples was lower than the worldwide average concentration (420 Bq kg−1). The current level of activity 137Cs varied from 0.05 to 0.40 Bq kg−1 in sediment samples and 0.98 to 1.33 Bq m−3 in seawater samples. 134Cs in all samples were not detected or below the detection limit. This fact indicated that radioactive cesium in Celebes Sea areas of North Sulawesi still originated from global fallout and insignificant influenced by the FDNPP accident. All radionuclide radiation values in the recent study are lower than the world average. Therefore, the potential danger of radiation generated from the surrounding environment has not yet caused a radiological health impact for the people living on the coast of North Sulawesi. Natural and artificial radionuclide activity data in this study will be used as the basis for sedimentary activity along the coast of North Sulawesi.
Accumulation and distribution of heavy metals in Gerres abbreviatus (Bleeker 1850) and Parastromateus niger (Bloch, 1795) in Kao Bay, North Maluku, Indonesia
Authors: Pertiwi R T A , Iksan K H , Ariyanto D
Published: November 2021

Heavy metals have a relationship with fish organs. The aim of this study was to determine the distribution of heavy metals in various organs of Gerres abbreviatus and Parastromateus niger. The research was conducted in Kao Bay waters from April to September 2019. Samples obtained were prepared at the aquatic science laboratory of Khairun University and were analyzed at the Environmental Productivity Laboratory of IPB University Bogor using the AAS instrument to determine heavy metals concentrations. The result of the heavy metals accumulation in Gerres abbreviatus meat was Zn > Cu > Pb > Ni > Hg > Mn > Cd. Meanwhile, the heavy metals accumulation in Roi fish (Parastromateus niger) meat was Zn > Mn > Ni > Hg > Pb > Cd > Cu.
Non-specific immune response of Pacific white shrimp Litopenaeus vannamei by supplementation of sodium alginate of Sargassum collected from Lampung Indonesia
Authors: Setyawan A , Riana  , Supono  , Hudaidah S , Fidyandini H P
Published: November 2021

This study aims to determine the effectiveness of supplementation of sodium (Na) alginateSargassumsp. from Lampung waters to enhance the non-specific immune response and the resistence of Pacific white shrimp (Litopenaeus vannamei) against white spot disease. This study used a completely randomized design with 3 treatments, namely feeding without alginate supplementation (A) or control, dietary Na alginateSargassumsupplementation at a dose of 2.0 (B), and 4.0 g kg−1feed (C), each with four replications, for 14 days. Hemolymph sampling was performed on days 0, 7 and 14 to observe the parameter of shrimp hematology includedtotal haemocyte count(THC),phagocytocyte activity(PA),phagocytic index(PI), and total plasma protein (TPP). The hepatopancreas histology profile and water quality were observed at the end of treatment. Data were analyzed by Anova at 95% of confidence interval and continued with Duncan test. Result showedthat the supplementation of Na alginat fromSargassumsp. significantly enhance several shrimp immune response namely THC, PA, and TPP. Meanwhile, the histology of the hepatopancreas of both shrimp treatment and control showed not significantly effect on tissue damage. The water quality was still in normal condition during the treatment. The results of this study indicate that the application ofSargassumalginate supplementation at a dose of 2gr/kg of feed is the best treatment to enhance the immune response of Pacific white shrimp.
Biodegradation mechanism of naphthalene using marine sponge symbiotic bacteria
Authors: Marzuki I , Nisaa K , Asaf R , Armus R , Kamaruddin M , Sapar A , Emelda A
Published: November 2021

Generally, all petroleum processing industries produce oil sludge or sludge. Polycy-clic Aromatic Hydrocarbons (PAH), one of the components contained in sludge, are hazardous and toxic waste material with toxic, carcinogenic and mutagenic properties. The research objective was to understand the biodegradation mechanism of naphthalene by utilizing a marine sponge symbiotic bacterial isolate. Partial bacteriaBacillusSp strain AB353f (BC), sponge isolate Neopetrosia sp andAcinetobacter Calcoaceticusstrain PHCDB14 (AC) isolate sponge Callyspongia (Aerizusa) as biomaterial for PAH degradation. Biodegradation method integrates bacterial suspension with 10,000 ppm naphthalene for 25 days. Every 5 days, the bio-degradation indicators were observed and the products of the destruction of naphthalene components were measured using FTIR and GC-MS. The results showed that BC isolates and AC isolates from sponge symbionts could degrade naphthalene. The biodegradation performance of BC bacteria tended to be more dominant than AC against naphthalene. Based on the functional groups resulting from FTIR, three types of biodegradation products were identified, namely: alcohol, aldehyde and carboxylic acid and one transition product in the form of a cate-chol. Maximum naphthalene bio-degradation occurs at an interaction period of 20 - 25 days.
Inclusions of probiotics and prebiotics in diet for coral trout, Plectropomus leopardus nursery
Authors: Marzuqi M , Giri I N A , Mahardika K , Mastuti I , Asih Y N
Published: November 2021

Coral trout is one of marine fishery commodities with high economic value. This grouper fish has limited ability in the utilization of artificial feed. The aim of this study was to obtain information on the effectiveness of probiotics and prebiotics inclusions in diet to increase growth of coral trout. Fish was reared in fiber tanks 300-L with a density of 30 fish/tank. Fish weight and length were 3.7±0.1 g and 6.3±0.1 cm, respectively. Each tank was equipped with a flowing water system and aeration as a source of oxygen supply. The feed was formulated with 48% protein and 9% lipid. Treatments were inclusion of probiotics in diet (diet A), inclusion of mannan oligosaccharide/MOS (diet B), inclusion of probiotic + mannan oligosaccharide/MOS (diet C), and diet D as control. The study was conducted in a complete randomized design (CRD) with 4 treatments and 4 replications. Fish fed trial diets with a frequency of 3 times a day at satiation. The parameters observed were growth, feed efficiency, feed digestibility, bacteria density and immunity. The data obtained were analysed with anova followed by LSD. The results showed that diet with the probiotic content promoted better growth and feed efficiency of coral trout compared to the other treatments. The highest growth of coral trout fingerlings was obtained by fish fed diet A (added with probiotics) with a weight gain of 794.86%. While fish fed diet containing probiotics and prebiotic (diet C) showed a lower growth response (weight gain 641.26%) than those fed diet with probiotics and prebiotics (MOS) separately. Survival during the study for all treatments ranged from 90.00% to 93.33%.
Fish hydrolysate supplemented diet improved feed efficiency and growth of coral trout (Plectropomus leopardus)
Authors: Giri N A , Astuti N W W , Sudewi  , Marzuqi M , Asih Y N
Published: November 2021

Fish hydrolysate contains hydrolyzed protein which comprised of peptides and free amino acids that are easily digested and absorbed by fish. This study aimed to determine the effectiveness of fish hydrolysate in improving feed efficiency and growth of coral trout. Five experimental diets were formulated to contain 47% protein and 12% lipid with different sources and levels of fish hydrolysate. Diet-1 and diet-2 were added with crustacean hydrolysate at 2% and 4% levels, respectively. Whereas diet-3 and diet-4 were supplemented with 2% and 4% of tuna hydrolysate. Diet-5 was formulated without fish hydrolysate supplementation (control). The diets were prepared as dry pellet with 3 mm diameter. Coral trout juveniles were produced in the hatchery of Institute for Mariculture Research and Fisheries Extension (IMRAFE), Gondol-Bali with the average body weight of 7.6 ± 0.9 g. The juveniles were maintained in 15 fiber tanks, 400L in volume, with a density of 40 fish/tank. The experiment was designed with a completely randomized design (CRD) with 5 treatments (different diets) and 3 replications for each treatment. The fish were fed the experimantal diets three times every day at satiation level for 84 days of feeding experiment. Results of the experiment showed that increased supplementation of fish hydrolysate from 2% to 4% in diet tended to improve fish growth performance. However, the best growth performance, in term of weight gain (WG) and specific growth rate (SGR), was obtained in fish fed diet supplemented with 4% crustacean hydrolysate. This growth performance was significantly higher than of the other treatments (P<0.05). The best feed efficiency (FE) and protein efficiency ratio (PER) were also obtained in fish fed diet supplemented with 4% crustacean hydrolysate. The results of the present study showed that supplementation of 4% crustacean hydrolysate in diet effectively improved the growth and feed efficiency of coral trout.
Acclimatization of transformed seaweed Kappaphycus alvarezii carrying lysozyme gene in culture flask and the cultivation in floating net cage in Pangkep coastal
Authors: Suryati E , Tenriulo A , Fadilah S
Published: November 2021

The in vitro transformation of the lysozyme gene in seaweed K. alvarezii has been successfully executed to increase the viability against ice-ice disease. There were two major stages in this research; (1) transformation of lysozyme gene in seaweed K. alvarezii which was carried out on laboratory scale and the cultivation of gene-transformed explants in the culture flask stored in “culture chamber”; (2) the acclimatization in floating net cages of green nets (mesh size of 1 mm) with cage size of 50 x 50 x 50 cm, the population density of 200 explants and cultivated for two weeks. The explants were then transferred to blue nets (mesh size of 2 mm) with a cage size of 50 x 50 x 50 cm for four weeks of rearing. The plants were then enlarged using a long-line method in the floating net cage, by tying the seaweed using a double line with a gap of 15 cm each. The measurement of weight, bud lengths, and water quality was carried out within 2 weeks. The result shows that the daily growth rate of the transformed seaweed during the regeneration stage in the culture flask was around 0.33-0.4%/day, meanwhile during the acclimatization stage in the green nets the was 0.65-1.6%/day, and even more, increased during the acclimatization stage in the blue nets with DGR of 2.28-2.3%/day. During the enlargement stage in the floating net cages, the lysozyme-transformed seaweed showed an even higher DGR with a value of 3.2-8.2%/day. The results of the integration of the lysozyme gene in seaweed were indicated by the presence of a 670 bp of amplification products, that is the same total length of the 35 S-F promoter fragments and Nos T-R in the expression vector. Based on these results, the lysozyme gene was successfully transformed in K. alvarezii seaweed.