bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and detection of fault for substation GIS insulating part based on integrated automation system data
Authors: Liu Hongbing , Xiao Yongli , Qiu Shou , Zhao Xiaoyu , Chen Xin , Liu Zheng , Sun Jun
Published: June 2022

Insulators are important components in gas-insulated metal-enclosed switchgear (GIS), and their safe operation is of great engineering significance. In an air leakage fault accident caused by the cracking of the insulating part of the grounding knife switch of 500kV HGIS equipment, the following measures were taken to find out the cause of the failure: disassembly inspection, equipment assembly review, insulation performance test and residual stress analysis during casting and curing. It turned out that the failure was caused by a lack of cache firmware in the production process. The thermal conductivity and thermal expansion coefficient of the central copper conductor and epoxy resin are different. When the two are solidly adhered, the incompletely reacted insulating parts shrink too quickly when the temperature difference is too large. The copper conductor locally produces excessive residual stress to the epoxy resin, which causes the insulation to crack. According to the causes of the fault, suggestions are put forward, such as replacing the central copper conductor with aluminum material, adding secondary pre-curing procedure in the production process, and adding Remote longitudinal Wave probe on the Insulated Basin side to monitor residual stress in real time.
An individual pitch control method for floating offshore wind turbine
Authors: Luo Xiaosuo
Published: June 2022

As the vast deep-water wind resource represents a potential development of a superior resource in comparison to the coast and land, the floating offshore wind turbine (FOWT) represents a viable solution for increasing renewable energy generation. However, above the rated wind speed region, the influence of turbulent wind loads is more severe on the floating offshore wind turbine. Thus, the control system’s primary objective should be to minimize fatigue loads and irregular power output swings to achieve smooth power output. This paper proposes a feedback method of individual pitch control for FOWT that, by utilizing a feedback control strategy, effectively reduces asymmetric aerodynamic loads and platform motion. The effectiveness of the method is verified through simulation verification.
Generative Rendering Network based on U-shape Discriminator
Authors: Mu Chen , Zhao Huaici , Liu Pengfei
Published: June 2022

This paper introduces a generative rendering network(GRN) based on a U-shape discriminator for novel view image synthesis. Recently, some generative adversarial networks start to explore 3D space and synthesize new images by rendering methods. Compared with 2D-only networks, they have achieved impressive results in synthesizing novel view images. However, they still have a common shortcoming: the discriminator cannot provide more detailed information for training a strong generator. For this problem, we design an U-shape based discriminator to extract both global information and pixel-wise information. This innovative discriminator will feedback more instructive clues to train a better generator. Benefit from this strategy, our synthesis results on ShapeNet v2 “cars” and “chairs” and celebA have achieved better performance than comparative methods.
Feature Matching technology of Visible and Infrared Fusion Image based on VIFB
Authors: Luo Yixue , Zeng Qinghua , Li Yineng , Qiu Wenqi , Zhang Yizhou
Published: June 2022

In view of the needs of all-time navigation tasks, visual navigation technology based on visible and infrared images has received extensive attention. At present, visible and infrared fusion technology is mostly used in remote sensing detection, target recognition and other fields, but it has not been widely used in the field of navigation and lacks a representative technology evaluation system. Therefore, a feature matching performance evaluation framework for visible and infrared fusion image based on the VIFB framework is proposed in this paper. A variety of typical indoor and outdoor target scenes are designed to test 20 visible and infrared image fusion algorithms. Then the ORB feature matching method is used to test the feature matching effect of image pairs before and after fusion. A variety of qualitative and quantitative evaluation indexes are designed to evaluate the VIFB framework. The feature matching performance of the images before and after processing is comprehensively evaluated. The experiments show that the fusion image can effectively deal with poor lighting and smoke occlusion. In various test scenarios, NSCT_SR, HMSD_GF and LatLRR algorithms show better feature matching performance, and CNN, MST_SR algorithms better integrate visible details and infrared salient structural information. The images fused by ADF, DLF, FPDE algorithms have good grayscale equalization effect.
Research on Nondestructive Testing Signal Processing Method for Intermittent Fault of Circuit Structure
Authors: Huang Zhangyu , Ling Long , Xiao Qixun
Published: June 2022

In the process of nondestructive testing of circuit structural units, considering that the eddy current intensity and distribution formed under the action of electromagnetic coupling will inevitably cause the change of voltage or impedance of electromagnetic induction testing coil, this kind of phenomenon reflects the signal change information caused by defects such as insulation wear, corrosion, cavitation and so on. In order to fully avoid the sudden faults such as short circuit, open circuit or arc discharge caused by hidden dangers, which force the equipment to stop for maintenance, this paper studies the principle of intermittent fault detection system of circuit structure, designs the circuit structure of typical modules, and establishes the defect prediction model based on Smoothing Technology. It provides a theoretical basis for effectively detecting intermittent fault signals, analyzing the propagation trend of intermittent faults and identifying defect modes, and can be extended to the acquisition and processing of intermittent fault signals of electronic equipment.
SwinF: Swin Transformer with feature fusion in target detection
Authors: Li Te , Wang Huajun , Li Guangzhi , Liu Songshan , Tang Li
Published: June 2022

In recent years, transformer has made great achievements in the field of NLP and is gradually applied to Computer Vision. However, due to the particularity of images, the computational complexity of transformer is quite high. The windowing operation proposed by Swin transformer effectively solves this problem. We find that Swin transformer has the same hierarchical structure as CNN, so we propose SwinF network with feature fusion based on Swin transformer. On the coco type dataset, Swin transformer achieves 40.3mAP, while SwinF achieves 42.5mAP in the field of target detection.
Study of simulation parameters of refining solidification microstructure on Ti-55531 via a suction casting
Authors: Fu Yabo , Liu Xiaoli , Cao Xiangbo , Jin Guobao , Liu Gang , Sun Shuyu
Published: June 2022

Ti-55531 is difficult to achieve samples by a vacuum suction casting. Therefore, the experimental parameters of the suction casting are simulated, and the properties of Ti-55531 alloy with the microscale refining solidification microstructure are studied. The results show that the preparation parameters simulated through the ProCAST on Ti-55531 are obtained. Pouring temperature of 1662 °C is selected as the experimental temperature. Suction casting speed of 2 m/s is selected owing to it with a greater influence on the filling rate. Model temperature of 20 °C is selected with the low temperature. The copper casting mold is selected as the heat transfer coefficient of mold has very small effect on filling rate. The solidification time is not significantly affected by the pouring temperature and the mold temperature. The properties of Ti-55531-0.1 % La are further improved, due to the solidification structure with the microscale refining solidification microstructure for an average spacing of 3.6 μm in the edge. The hardness and strength in the edge both are 11.1 % higher than that in the centre due to refined structure. This study provides a new idea for the formation of a fine microstructure of titanium alloy.
Effects of modified plant fiber on properties of wood plastic composite
Authors: Li Rui
Published: June 2022

The surface of plant fiber was modified by HDTMS, and the modified plant fiber-PE wood-plastic composite was prepared by blending with PE. The experimental data of the sample characterization test, natural aging performance and thermal interaction performance were analyzed. The use of modified plant fibers to prepare PE-based composite materials can improve the performance indicators of materials and has certain social value.
Effect of mixed plastic hardening on the cyclic contact between a sphere and a rigid flat
Authors: Mo Yafei , Du Rou , Liu Xiaoming
Published: June 2022

This paper studies the effect of mixed plasticity mode (combined with isotropic and kinematic hardening law) on the cyclic contact between an elastic-plastic sphere and a rigid flat. Assuming power-law hardening with different levels of mixed plasticity for the sphere, we derived a semi-analytical expression of load versus interference during the first loading and unloading process. During cyclic loading, our results indicate that the isotropic plasticity model shows no variation of residual interference, while kinematic plasticity has the cyclic effect on the residual interference, and this effect is bigger for the material with a higher hardening exponent. In addition, we provided the semi-analytical expression for the evolution of residual interference, which is accurate for the strain hardening exponent from 0.1 to 0.5.
Vibration characteristics of cracked compressor blades with different materials
Authors: Zhou Z.T. , He X. , Liu Y.B.
Published: June 2022

Aiming at the influence of different material properties on the vibration characteristics of cracked gas turbine compressor blades, the vibration characteristics of cracked compressor blades with three different materials were studied by numerical calculation. The first order bending vibration of a cracked cantilever beam was simplified to a single degree of freedom system. The breathing crack stiffness model was introduced to change the elastic modulus and other parameters of the material. The fourth-order Runge-Kutta method and fast Fourier transform were used to obtain the cantilever beam vibration characteristic diagram, and the relationship between the material properties and the structural vibration was analyzed. The results show that the elastic modulus of the material is proportional to the stiffness, and the stiffness of the material affects the vibration displacement response of the cantilever beam, and the larger the stiffness is, the smaller the vibration displacement is.
Effect of shock-induced substructure evolution on the dynamic reloading mechanical behavior of Ti-17 alloy
Authors: Li Zheng , Tan Chengwen , Ren Yu
Published: June 2022

The effect of shock-induced substructure evolution on the dynamic reloading mechanical behavior of a metastable β titanium alloy, Ti-5Al-2Sn-2Zr-4Mo-4Cr (Ti-17), was systematically investigated in this paper. The preshock treatment with the shock stress amplitude of 6, 10 and 14 GPa were applied on the Ti-17 alloy with equiaxed β microstructure. Then the dynamic reloading tests at strain rate of 3000 s-1 were carried out on these shock-prestrained samples. The results show that, the shock-induced substructure in Ti-17 with equiaxed β microstructure involves shock-induced α" martensite, shock-induced ω phase, dislocation proliferation and slip band. The shock-induced substructure evolution directly influences the mechanical properties of Ti-17 alloy during dynamic reloading.
The mechanical property of different morphology Ti-Ni solder in brazing of BN ceramic and stainless steel
Authors: Zhao Yuhang , Fan Ruicheng , Gao Ying , Li Yifan , Wang Rui , Zhang Yunfeng
Published: June 2022

BN ceramic and stainless steel metal had been connected by vacuum brazing technology. The surface morphology and the micro-structure of solder were observed by optical microscope and scanning electron microscope. The mechanical property of solder was tested by the experiment. The experimental results show that: titanium powder/ Ni powder alloy solder can not form a valid connection due to osteoporosis and porous surface after high temperature heating. Ti powder /Ni foil solder can produce certain effects of connection, but BN ceramic occurs exfoliation in the process of cooling. Because of the affection of impurity elements, eutectic melting temperature of Ti-Ni based solder decreases, and the multiple solder alloy has formed with high density.
Research on the adsorption of RhB on CTMAB modified zeolite: adsorption kinetics, isotherm and thermodynamics studies
Authors: Ma Hongfei , Li Wei , Li Zhuqing , Li Judi , Han Qiuju
Published: June 2022

Cetyltrimethylammonium bromide (CTMAB) modified zeolite was used as the adsorbent, the adsorption behavior of simulated rhodamine B (RhB) dye wastewater was studied. The effects of adsorbent dosage and pH on RhB adsorption by the modified zeolite were investigated. The results show that the increase of the dosage of modified zeolite can improve the removal rate of RhB. The change of pH has a certain influence on the adsorption effect of RhB. The pseudo-second order kinetic model can accurately describe the adsorption kinetics. The study of adsorption equilibrium shows that Freundlich model can better fit the adsorption process than Langmuir model, and the maximum adsorption capacity was 15.97mg/g (303k). The thermodynamic calculation results show that the adsorption of RhB on cetyltrimethylammonium bromide (CTMAB) modified zeolite was an endothermic process, and the increase of the temperature was conducive to the reaction.
Investigation of Flow Characteristics of Flow Passage Components in Francis Turbine under No-load and 50% Load operating conditions
Authors: Li Hongxiang , Xu Liangyu , Zhao Feng , Zhang Fan , Deng Yaxin , Li Haoyu , Cheng Yongguang , Zheng Yuan , Kan Kan
Published: June 2022

Due to the varying demand of power grid for the electric supply of hydraulic power stations, the units are often under low-load operating condition and no-load standby state, causing a significant flow instability in hydraulic generator units. To further investigate the inside flow characteristics of hydraulic turbines under such operating conditions. In this study, a CFD (computational fluid dynamics) numerical simulation with applying RNG (Renorm alization Group) k-ε turbulence model is performed to study the inside flow characteristics of each flow passage components of a Francis turbine under no-load and 50% load conditions. The results indicate that under the two operating conditions, the flow distribution inside and outside the draft tube pier is significantly nonuniform. Simultaneously, the large-scale vortex in the runner area caused by the high-speed flow in the vane-free area with small opening and the nonuniform flow velocity distribution in the straight cone section of the draft tube are the main reasons for the increase of hydraulic loss and the decrease of efficiency.
Fire ant rafts elongate under fluid flows
Authors: Ko Hungtang , Yu Ting-Ying , Hu David L
Published: June 2022

Fire ants survive flash floods by linking their bodies together to build waterproof rafts. Most studies of fire ant rafts consider static water conditions, but here, we consider the influence of flow. In particular, when floating on shallow water, the raft can run aground on vegetation, generating stresses in the raft as the water continues to flow around it. In this combined experimental and numerical study, we film the 10 h response of a fire ant raft caught on an anchor and subjected to water flows of 6 cm s−1. In this situation, ant rafts elongate from circular to more streamlined shapes, doubling in aspect ratio before eventually contracting back into smaller circular shapes as they enter dormancy. Ants in upstream regions of the raft exhibit less exploration activity than those downstream, suggesting that ants migrate to areas of lower fluid stress. While the raft is rough, hydrophobic, and heterogeneous in height, we may gain some insight by performing both fluid-structure interaction and agent based simulations on smooth rafts. Elongation to the degree observed is associated with a 48% drag reduction. Moreover, a purely elastic raft does not elongate, but conversely increases its bluff body cross-sectional area. We conclude that ant raftsmust reconfigure to generate the elongated shape observed. This work may provide insights into designing intelligent robotic swarms that can adapt to fluid flows.
Microstructure, mechanical strength, chemical resistance, and antibacterial behavior of Ti–5Cu–x%Nb biomedical alloy
Authors: Pandey Anurag Kumar , Gautam R K , Behera C K
Published: June 2022

Titanium-based biomedical alloys are susceptible as they are used as a substitute for human bone. In this study, titanium alloy, Ti–5Cu–x%Nb (x = 0, 5, 10, 15) (%wt) was developed by powder metallurgy route. The effect of alloying niobium with Ti–5Cu alloy and its effect on the microstructure, mechanical strength, corrosion resistance, and antibacterial properties have been evaluated. The results show that the sintered alloy has both α-Ti and Ti2Cu phases. With increasing niobium content in the alloy, β-Ti was also detected. Additionally, it was found that the micro-hardness and compressive strength of the studied alloy was better than commercially pure titanium (cpTi), while the Young’s modulus was lower than cpTi. These properties are highly favorable for using this alloy to replicate the human cortical bone. The alloy was also tested for anticorrosive property in Ringer’s solution. The antibacterial activity was also examined for Staphylococcus aureus and Escherichia coli bacteria. The alloy showed promising anticorrosive and antibacterial ability.
Climate policy for a net-zero future: ten recommendations for Direct Air Capture
Authors: Sovacool Benjamin K , Baum Chad M , Low Sean , Roberts Cameron , Steinhauser Jan
Published: June 2022

Direct Air Capture with Carbon Storage (DACCS) technologies represent one of the most significant potential tools for tackling climate change by making net-zero and net-negative emissions achievable, as deemed necessary in reports from the Intergovernmental Panel on Climate Change and the European Green Deal. We draw from a novel and original dataset of expert interviews (N = 125) to distil ten recommendations for future DACCS policy. After providing a literature review on DACCS and explaining our methods of data collection, we present these recommendations as follows: (a) follow governance principles that ensure ‘negative’ emissions; (b) prioritize long-term carbon storage; (c) appreciate and incentivize scale; (d) co-develop with capture, transport, and storage; (e) phase in a carbon price; (f) couple with renewables; (g) harness hub deployment; (h) maintain separate targets; (i) embrace certification and compliance; and (j) recognize social acceptance. All ten recommendations are important, and all speak to the urgency and necessity of better managing and shaping the potentially impending DACCS transition.
On Schrödinger operators with δ′-potentials supported on star graphs
Authors: Pankrashkin Konstantin , Vogel Marco
Published: June 2022

The spectral properties of two-dimensional Schrödinger operators with δ′-potentials supported on star graphs are discussed. We describe the essential spectrum and give a complete description of situations in which the discrete spectrum is non-trivial but finite. A more detailed study is presented for the case of a star graph with two branches, in particular, the small angle asymptotics for the eigenvalues is obtained.
Millimeter-wave gas spectroscopy for breath analysis of COPD patients in comparison to GC-MS
Authors: Rothbart Nick , Stanley Victoria , Koczulla Rembert , Jarosch Inga , Holz Olaf , Schmalz Klaus , Hübers Heinz-Wilhelm
Published: June 2022

The analysis of human breath is a very active area of research, driven by the vision of a fast, easy, and non-invasive tool for medical diagnoses at the point of care. Millimeter-wave gas spectroscopy (MMWGS) is a novel, well-suited technique for this application as it provides high sensitivity, specificity and selectivity. Most of all, it offers the perspective of compact low-cost systems to be used in doctors’ offices or hospitals. In this work, we demonstrate the analysis of breath samples acquired in a medical environment using MMWGS and evaluate validity, reliability, as well as limitations and perspectives of the method. To this end, we investigated 28 duplicate samples from chronic obstructive lung disease patients and compared the results to gas chromatography-mass spectrometry (GC-MS). The quantification of the data was conducted using a calibration-free fit model, which describes the data precisely and delivers absolute quantities. For ethanol, acetone, and acetonitrile, the results agree well with the GC-MS measurements and are as reliable as GC-MS. The duplicate samples deviate from the mean values by only 6% to 18%. Detection limits of MMWGS depend strongly on the molecular species. For example, acetonitrile can be traced down to 1.8 × 10−12 mol by the MMWGS system, which is comparable to the GC-MS system. We observed correlations of abundances between formaldehyde and acetaldehyde as well as between acetonitrile and acetaldehyde, which demonstrates the potential of MMWGS for breath research.
Plant Success Rate in Program Forest and Land Rehabilitation in Unity Batutegi Forest Management
Authors: Widodo L M , Safe’i R , Winarno G D , Yuwono S B
Published: June 2022

Forest and Land Rehabilitation is one of the right solutions to overcome the problem of critical land. Efforts to overcome critical land are difficult to obtain in a short time to return the situation to its original state, but efforts are being made by the government to overcome the existence of critical land and the expansion of critical land, including through land conservation and reforestation. This study aim to determine the success of plants in a forest and land rehabilitation program in the village of Datar Lebuay in the Air Naningan district of Tanggamus regency. The study was carried out in June 2021. Field data collection was carried out by making plots using the Systematic Sampling with Random Start method, namely the first plot was made randomly and the next plots were made systematically. Sampling Intensity (IS) is 5%. The results showed that the success rate of RHL activities with a percentage of life was 79.74% which was classified as successful. Factors that are thought to influence the low success rate of plants are the condition of the planted seeds that are already in a damaged state and the planting season is not right.
Design and Build Remote Watering System Based on Internet of Things (IoT) (Case Study Of Yogyakarta Code Tourism Park)
Authors: Haryanto E , Fitriastuti F , Setiyorini A , Haryanto E M O N , Lukmanfiandy S
Published: June 2022

The combination of IoT (Internet of Things) technology and solar cell technology can be used to ease human work in everyday life. This research will design and build an Internet of Things (IoT)-based automatic plant sprinkler system by utilizing solar cells as electrical energy. The implementation of this system is carried out at the Code Tourism Park in Cokrodiningratan Village, Jetis District, Yogyakarta City. This research was conducted using the waterfall method with systematic stages. Solar panels have succeeded in producing AC electricity with a voltage of 220V so that it can be used to supply electricity to IoT device controllers. The watering mode consists of an automatic mode with a schedule that can be set from a web-based IoT platform and a remote watering mode via the internet. Both watering modes worked well and successfully watered the plants at the study site. For watering a garden with an area of 197.2 m2, the water consumption required per minute is approximately 20 liters. The coverage of watering plants in the Code Tourism Park is 197.2 m2. At the watering location, 15 sprinkler points are installed, so 1 sprinkler point can cover an area of approximately 13.15 m2.
Distribution Mapping of Cadmium on Water and Soil in Rice Fields Around The Industrial Area of Sidoarjo Regency
Authors: Fitrianah L , Yahya M , Noer Hamidah L , Rosyidah E , Rahmayanti A , Octavia L , Widiyanti A , Tamyiz M
Published: June 2022

The development of industrial estates in the western part of Sidoarjo Regency include Taman District, Krian District, Balongbendo District, and Tarik District have a major influence on population growth. The existence of the rice fields around the industry indirectly affects the quality of the environment due to industrial activities. The purpose of this research is to identify the spatial distribution of Cadmium heavy metal content in the water in rice fields around the industrial area of Sidoarjo Regency and to identify the spatial distribution it. The parameters taken are cadmium content in soil and water samples in the rice fields. The method used in the study was a survey and laboratory, mapping used the kriging method. The result of the research showed The highest cadmium content is in the rice fields of the Taman sub-district. cadmium content in water is 1.90 ppm while in the soil is 2.43 ppm. The quality level at the four locations was declared to exceed the environmental quality standard. The distribution map showed the area of the Taman sub-district is the highest compared to other sub-districts.
Effectiveness of the Prohibition of Farming Land Splitting Policy (Study on Land Sale and Purchase)
Authors: Wibawanti E S , Murjiyanto R , Anggraeni R
Published: June 2022

This study aimed to determine whether prohibiting the division of agricultural land into too small (less than 2 Ha) parts is still practical and relevant to society’s current situation. The literature used in this study was supported by data from Land Deed Making Officials (PPAT). According to the results, the policy is no longer effective in limiting the minimum agricultural land ownership and preventing agricultural land splitting. This policy is also no longer relevant because: first, the common area of agricultural land owned by farmers is less than 05 ha; second, many residents are forced to sell their agricultural land; and third, the prohibition encourages agricultural landowners to transfer land functions. Therefore, it is time for the government to reevaluate the minimum land ownership policy and the prohibition on breaking up agricultural land, considering the conditions and developments of community needs and the existing land area.
Environmental Licensing After the Job Creation Act in the Perspective of a Decentralized Unitary State
Authors: Iskatrinah  , Periani Aniek , Hariadi Wahyu , Ningrum Esti
Published: June 2022

This research is motivated by the existence of one of the laws that are affected by Law Number 11 of 2020 concerning Job Creation, namely Law Number 32 of 2009 concerning Environmental Protection and Management, which is related to changes in the concept of environmental licensing, which creates differences There is a perception among the public that there are contradictory objectives in the two laws, that goals that are oriented towards attracting investment and employment have the potential to ignore sustainable environmental conservation. Changes in the concept of environmental licensing into environmental approvals in the work copyright law which then gives more authority to the Central Government regarding the formation of a Feasibility Test Team formed by the Feasibility Testing Agency of the Central Government, and the types of activities and businesses are also determined by the Central Government, so there are efforts to reduce the authority provincial and district/city areas, this is not in accordance with the implementation of decentralization on the principle of regional autonomy mandated by the constitution. This study aims to restore the function of environmental licensing as a controlling instrument in environmental activities/businesses that are attached to the central, provincial and district/city governments, using a qualitative normative juridical method with a library research approach.
Emulsion Polymers of Carboxymethyl Cellulose and Methyl Methacrylate with Tetrabutylammonium Hydroxide Surfactant as Soil Stabilizer
Authors: Abidin A Z , Nuriman R B E T , Pradipto N A , Putra R P
Published: June 2022

Carboxymethyl cellulose (CMC)-based emulsion polymers stabilized with surfactants are of great importance for designing effective soil stabilizing agents that can efficiently bind soil particles. Grafting of CMC with other monomers is considered a promising alternative to enhance the binding capability of polymer with soil particles that can improve the mechanical properties of soil. In this work, CMC-methyl methacrylate (CMC-MMA) emulsion polymers were synthesized using various MMA to CMC weight ratios. Tetrabutylammonium hydroxide was employed as a cationic surfactant to control the sorption and diffusion of water in the emulsions. The materials were further investigated for their compressive strengths using dry and wet procedures by mixing them with laterite soil. The results showed that the materials were obtained in high monomer-to-polymer conversion using MMA to CMC weight ratios of 6.67 - 8.89. Characterization using Fourier transform infrared verified the formation of MMA-CMC-O-(MMA)
n
. The viscosity of the emulsion polymers was in the range of 3.52-8.61 cP. Overall, the rise in the number of cross-linked MMA and CMC monomers resulted in the enhanced compressive strength of the soil due to increased Van der Waals forces and hydrogen bonds between the polymer and soil particles.
Application of cytochrome oxidase subunit 1 partial gene for species validation of Macrobrachium sintangense from Lake Lido, West Java
Authors: Hakim Agus Alim , Sidabutar Yessi Natalina , Mashar Ali , Zairion  , Imran Zulhamsyah , Wardiatno Yusli
Published: June 2022

Lake Lido is one of the habitats for Sunda river prawn (Macrobrachium sintangense), but the species was reported not to be found in December 2015-May 2017. This prawn has an economic value both alive for consumption and dead for bait. Shrimp identified morphologically as M. sintangense required reinforcement using molecular techniques for species certainty. This study aimed to validate Sunda river prawn (Macrobrachium sintangense) based on a molecular approach using cytochrome oxidase subunit 1 (COI) partial gene markers. Species certainty is important as basic information in management. The specimens (n=15) were obtained from Lido Lake and transported to the laboratory for genetic analysis. The analysis includes DNA extraction, polymerase chain reaction (PCR), electrophoresis, and sequencing. Three samples were successfully aligned using MEGA X software. Based on BLASTn in NCBI, the sequences have high similarity with Macrobrachium sp. sequence by 95%. However, nucleotide bases of M. sintangense were found in a database with access code MF622027.1, but it did not match with the samples. Phylogeny analysis showed the different clade positions with M. sintangense database. The prawn samples have been identified morphologically as M. sintangense but have not been validated as the same species by COI partial gene markers. So, it is necessary to validate using other gene markers to obtain species certainty for management.
Temporal variation in abundance of bully sleepers (Pisces: Eleotridae) larvae and juveniles in Cisolok Estuary, Palabuhanratu Bay, Indonesia
Authors: Prabowo T , Simanjuntak C P H , Affandi R , Baihaqi F , Annida S B , Ervinia A , Budiman M S
Published: June 2022

Larvae and juveniles of bully sleepers are the primary targets for the local community surrounding Cisolok River, and this traditional fishing activity is called nyalawean. The present study aims to uncover fish larval diversity and recruitment of bully sleepers in the Cisolok river estuary. Fish sampling using a lift net was conveyed monthly from December 2020 to February 2021. Fish specimens were identified to the lowest taxon through a morphological approach and DNA Barcoding. Catch per unit effort measured the abundance of fish larvae and juveniles (CPUE, Ind.h−1). Only one species was found during the study period, namely Bunaka gyrinoides. A total of 7,353 larvae and juveniles of B. gyrinoides were captured, consisting of flexion (45 individuals; 4-5.9 mm BL), postflexion (6,887; 6-11 mm BL), and early juvenile (441; 11.1-14.8 mm BL). Postflexion larvae were the most abundant specimens, contributing 88.4-95.5%; 96-81.1%, 94.2-97.8% to the total catches in December, January, and February. Larvae and juveniles were more abundant during daylight (671-1591 Ind.h-1) rather than nighttime (147-567 Ind.h-1). These findings indicate that bully sleepers recruit and migrate upstream into the freshwater area of the Cisolok River during the day and nighttime synchronized with the tidal fluxes.
Antibacterial activity of Nephrolepis biserrata extract against Aeromonas hydrophila and Vibrio parahaemolyticus
Authors: Maulianawati D , Suharni S
Published: June 2022

Fish farming has become a significant sector in producing animal protein. However, a disease caused by bacteria such as Aeromonas hydrophila and Vibrio parahaemolyticus has become obstacle factors in these farming activities. Among the various procedures for preventing bacterial attacks, the use of natural ingredients deserves to be considered. This study aimed to test the ability of gray nail extract (Nephrolepis biserrata) in inhibiting the growth of A. hydrophila and V. parahaemolyticus in vitro. N. biserrata were extracted using methanol (EPM) and chloroform (EPC). EPM and EPC were then challenged with A. hydrophila and V. parahaemolyticus bacteria to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The test results showed that an inhibition zone of EPM against A. hydrophila and V. parahaemolyticus were 8.2 and 8.3 mm, respectively. EPC has been unable to inhibit the activity of both bacteria, whereas EPM could. The MIC value for both bacteria was 50 mg/mL, and MIB concentration was more than 50 mg/mL. The results of this study indicate that the N. biserrata extract could inhibit bacteria.
Application of compost in the different of pen culture substrates type for the intensification of sea cucumber, Holothuria scabra (Jaeger 1883) culture
Authors: Sabilu K , Supriyono E , Nirmala K , Subhan  , Ketjulan R , Hamzah M , Rahman A , Patadjai R S , Alwi L O , Sabilu M
Published: June 2022

Intensification of aquaculture is directed at the effort to increase productivity by carrying capacity of production factors. This study was conducted to evaluate the growth performance of Holothuria scabra cultured intensively through the application of compost fertilizer. H. scabra were reared for 90 days (20 individuals/m2 of density), using a pen culture method on the three different substrates, namely fine sand, seagrass mud, and coarse sand, where each treatment was made as four replicates. The amount of compost used for the type of each substrate was the same. The results showed that applying compost in sea cucumbers culture using the pen culture method was proven to be effective in increasing the growth performance of sea cucumbers H. scabra, with the weight gain, growth rate, and survival, respectively, ie: 49.10±1.62 g; 1.26±0.03% g/day and 90.00% on seagrass mud substrate; 46.00±6.92 g; 1.23±0.11% g/day and 89.00% on a fine sand substrate and the lowest is 42.05±g; 1.13±0.08% g/day and 87.50% were found on a coarse sand substrate. The growth response was not significantly different between the three substrate types (Duncan’s test, p>0.05), indicating that the availability of nutrient sources in substrates is one of the key factors for the intensification of H. scabra culture.
Fishing trials of portable fad on purse seine fisheries
Authors: Yusfiandayani Roza , Baskoro Mulyono S. , Sutioso William , Kholilullah Ibrahim
Published: June 2022

Fish Aggregating Devices (FADs) are tools for collecting fish by using various attractors from solid objects that attract fish to gather. Portable FAD uses sound frequency attractors that can be operated in various fishing areas. Portable FAD is not placed permanently in the waters and can be stored until fishing operations are carried out. The purpose of this activity is to calculate the buoyancy and gravity of portable FAD, determine the composition of the catch, and determine the distribution pattern of fish in the morning, afternoon, and evening. For 17 (seventeen) days, this activity was carried out in Yamdena waters, Ambon. The calculation results of the total buoyancy force of portable FAD were 20554.69 gs, total sinking force was 5460.69 gs, and the extra buoyancy value was 73%. The dominant fish caught using purse seiner were skipjack tuna (Katsuwonus pelamis) of 37.41%, yellowfin tuna (Thunnus albacares) of 33.53%, scad fish (Decapterus russeli) of 11.62%, tuna (Euthynnus affinis) by 8.12%, and sunglir fish (Elagatis bipinnulata) by 5.14%. Portable FAD can attract fish from 15 minutes and continue to increase to a peak at 105 minutes with 160 fish approaching. The highest fish approach to portable FAD was recorded in the morning at 105 minutes at a depth of 20-25 m were 89 fish, the lowest was in the afternoon at 15 minutes at a depth of 5-10 m were 7 fish. The best use of portable FAD is in the morning and evening.
Procedure for catches data collection and its implementation: a case study of fishing ports in Jakarta
Authors: Darmawan  , Andayani Nina D , Mustaruddin
Published: June 2022

Unreported catches data is one of the main problems which causes data inaccuracy in estimating fish stock. There are indications of missing data at fishing ports. Hence further research is needed to investigate how fish catch data was collected and collated. This study aims to identify critical points for missing data in the catches data collection process at fishing ports, analyze the performance of the data collection system, and recommend suggestions for improvements to the data collection system. Direct observations on catches data collection activities and in-depth interviews with key stakeholders were conducted to gain information. The comparative analysis compared information gathered with the ports data collection procedures. The research shows that the probability of missing data during the data collection process in PPS Nizam Zachman, PPN Muara Angke, and PP Cilincing is 13.3%, 33.3%, and 100%, respectively. This is mainly because no national Standard Operation Procedures are applied to regulate the collection of catches data; hence officers cannot collect catch data correctly and adequately. Other problems that potentially cause data loss are poor infrastructure, limited human resources or enumerators, and low awareness of the data value.
Efficiency of set long lines before moratorium and regulations of shrimp trawls and fish nets in Arafura Waters: case study in Probolinggo
Authors: Hufiadi  , Baihaqi  , Mahiswara  , N Yusuf Helman , Pane Andina R P
Published: June 2022

Before the moratorium and regulations of prohibition of trawls and fish nets in Arafura Waters, there were three major fishing gears that intensively caught demersal fish in the Arafura Sea, that are fishnet, shrimp trawl, and set long lines. Interaction between fish net and set long lines in exploiting the same species target can affect the fishing capacity of set long lines. The technical efficiency measurement of set long lines fisheries is expected to reference the level of set long lines fishing capacity before the moratorium and regulations of prohibition of trawls and fishnets. The data was collected in fishing company based Probolinggo in the period of 2010-2014. Measuring technical efficiency of set long lines was expected to be a reference point for set long lines fishing capacity basis before the provisions of the moratorium and destruction on shrimp trawl and fishnet. The fishing efficiency measurement by season approaches and the analysis showed that during the western and east monsoon season, fishing efficiency of set long lines was relatively low, which was <0.50. Reducing excess fishing capacity in both seasons will produce output optimally.
In situ transplantation of soft coral Sarcophyton sp in concrete pool
Authors: Subhan Beginer , Saputra Didit Aditya , Arafat Dondy , Madduppa Hawis , Ayu Inna Puspa , Ervinia Ayu , Akbar Nebuchadnezzar , Soedharma Dedi , Revany Retia , Lestari Dea Fauzia , Hidayat Silki Anisa , Wiyanto Dwi Budi
Published: June 2022

Coral habitats; however, this is not easy. Strong currents, temperature fluctuations, competition with other organisms, predators, and food availability are problems in coral transplantation. The obstacles are eliminated by transplanting coral under controlled environmental conditions. This study was aimed to determine the growth of transplanted soft corals Sarcophyton sp in a concrete pool. The increase in length, width, and area of coral fragments only occurs at certain times. The growth rate of length, width, and soft corals fluctuates every week and tends to decline. The growth rate reached the highest at week-6, 0.388 cm for the coral without additional feeding and 0.744 cm for corals with supplementary feed. However, after that, the rate of growth fluctuated again. Despite the decline in development, all soft corals transplanted had a 100% survival rate until the end of life care. In addition, all the soft corals were in healthy condition.
Fish larvae spatial distribution and composition in FMA 711
Authors: Taufik M , Wagiyo K , Priatna A , Ernawarti T
Published: June 2022

The South China Sea is the western part of Sunda Shelf, divided into shallow water in the southern part and deeper in the north. The Indonesian Fishery Management Area (FMA) 711, located in the southern part of this area inside the country’s territorial waters, was one of fertile and high in biodiversity in terms of fish species. The collection of fish larvae was conducted as part of biological parameters on a stock assessment cruise survey in October 2017 using the Baruna Jaya IV research vessel. Results showed that there were 47 families of fish larvae found in 31 sampling stations. Abundance ranges from 16,2 – 2342,2 ind/1000 m3 with an average of 413.6 ind/1000 m3. The number of Families varies in every station from 2 – 22 with an average of 11. The dominant taxon was Engraulidae with 21.47%; followed by Nemipteridae, Scaridae, and Pomacentridae with 11,55%, 7,72%, and 7,34% respectively. Family with the highest distribution was Nemipteridae and Pomacentridae which cover 80,65 % of the sampling area. Others that also have high coverage are Carangidae, Scaridae, and Labridae with 64,52 %, 61,29 %, and 58,06 % respectively. This result indicates the high biodiversity of the area.
Coral disease on fungiidae at Sop Island, Sorong, Papua Barat
Authors: Subhan Beginer , Rahmawati Fadhilah , Arafat Dondy , Bramandito Aditya , Khairudi Denny , Royhan Q Muhammad , Madduppa Hawis , Santoso Hendi , Fauzi Firli Rahman Hakim , Revany Retia , Wiyanto Dwi Budi , Prehadi  , Rizqydiani M
Published: June 2022

This research is located at Sop Island, Sorong, West Papua. The data was collected using the Belt Transect method, stretching a line for 50 meters with a width of vision for 2.5 meters to the left and 2.5 meters to the right. The depth of the transect is 5 meters, recorded all genera from Family Fungiidae. Five genera were found on The Sop Island, namelyCtenactis, Fungia, Herpolitha, Polyphyllia, andSandalolitha, but onlyCtenactis, Fungia, andSandalolithawere found on the three sites of observation.Fungiais the most abundant genera found at Sop Island. So, however, the study also found many unhealthy symptoms that infectedFungia. Of the three observation sites, six categories of unhealthy coral are found: Tissue Loss - non-predation - Coloured Band Disease, Tissue Discoloration - White, Tissue Discoloration non-white, Compromised Health Growth Anomalies, and Unknown. The most common categories infected with the Fungiidae at Sop Island are Tissue Loss - non-predation - Coloured Band Disease, Tissue Discoloration - White. Agonizingly, researchers found coral disease at every site.
Analysis of trophic status in estuaries in Banten Bay
Authors: Sugiarti  , Rohaningsih Denalis , Rahmadya Aldiano
Published: June 2022

The fish population could expand in a healthy habitat with adequate water quality and fertile conditions. Banten bay estuaries were known as an area with high fishing activities and were a source of income for fishermen. Many human activities occur in the vicinity of estuaries, which can impact water quality and aquatic fertility. This study aims to determine the trophic status of the fourth estuary in Banten Bay. Water was sampled in the estuarine area of the Banten Bay, namely Wadas, Karangantu, Cengkok, and Pamong, in May, July, and October 2013, as well as in April 2021. pH, water temperature, salinity, conductivity, turbidity, and dissolved oxygen are all measured in situ. Other values like nitrite, nitrate, ammonia, chlorophyl-a, Total Nitrogen, and Total Phosphorous were measured in the lab. TRIX techniques were used to determine trophic status. In four Banten Bay estuaries, a nutrient-rich water environment could still support an abundance of fish.
Community of juvenile hard corals (Scleractinia) in different geomorphological type and reef benthic communities
Authors: Abrar M , Hadi T A , Handayani T , Zamani N P , Suharsono  , Bengen D G
Published: June 2022

Juvenile corals are an important stage in the life history and demographics of coral populations in nature however, their survival is influenced by the physical environment and benthic coral reef communities. The study of juvenile coral communities with a maximum size of 10 cm on the reefs of Pulau Weh, Sabang, Aceh was conducted to observe juvenile coral communities and determine their relationship with geomorphological types and benthic reefs communities. A total of 9 sites with 72 sampling squares were distributed in different geomorphological; tectonic type with hard substrates of lava and limestone, volcanic type with predominantly sand substrate, and dead coral with algae with the presence of hot springs in the vicinity. In total, we found 25 genera of juvenile corals from 12 families, and the abundance reached 449 colonies with an average of 37.41 colonies per site. The mean density was 6.66 ± 5.99 colonies/m2 (±SD) and varied significantly between sites (p=4.878-7; <0.05), which was dominated by the genera Porites, Pavona, Acropora, Montipora, and Favia. Live coral cover (HC), dead coral algae (DCA), and hard rock substrate (RK) did not affect, however rubble coral (R) was significantly affected (p=1.9-2; <0.05). Geomorphological conditions and benthic reef cover did not show a significant effect (p = 0.48; < 0.05), although juvenile corals were very common and better in the tectonic type than the volcanic type. The survival of juvenile corals was low, where the smaller size was significantly high compared to the larger size (p=4.5-5; <0.05). Our study provides up-to-date information and data on juvenile coral communities based on geomorphological conditions and local benthic reef communities.