bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance study of the supplemental combustion type compressed air energy storage system
Authors: Guo Zuogang , Xu Min , Xu Shen , Tan Yingjie , Liu Tong , Hao Xinyue , Chen Guangming
Published: September 2023

Compressed air energy storage technology is considered to be the most promising energy storage technology, but it has not been applied commercially on a large scale, partly because of the low system efficiency, with the existing efficiency being about 70%. To improve the round trip efficiency of the system, this paper proposes a supplementary combustion compressed air energy storage system based on adiabatic compressed air energy storage. The system adds supplementary combustion equipment to increase expansion machines’ inlet air temperature by burning fuels such as syngas, hydrogen, and natural gas to increase the power generation of the system. The thermodynamic performance analysis has been conducted through the thermodynamic model of the system, and the effects of parameters such as compressor discharge temperature, supplementary combustion, and air-fuel ratio on the system performance have been further investigated. The research results show that the efficiency of the system is improved by nearly 6% compared with the conventional adiabatic compressed air energy storage system. Meanwhile, the system’s round-trip efficiency can be further increased by appropriately raising the compressor discharge temperature and supplemental combustion quantity.
Efficiency and Feasibility Analysis of Wind Turbines in Tandem in a Vortex Tube
Authors: Chen Jinlu , Zou Libing , Su Dianpeng , Xiao Mingye , Yang Ruyan , Zheng Xiang Yuan
Published: September 2023

Polar scientific research is of great importance for the human. The exploitable wind energy of the polar region accounts for more than 20% in the worldwide sense. However, the harsh polar storms, extreme wind speed (up to 100 m/s), ice crystals and sand in the wind all hinder the exploitation of wind resources. Therefore, in order to protect the power generation infrastructure and to maximize the power generation window, this paper proposes an innovative concept of power generation first. This concept, placing multi wind turbines in tandem in a vortex tube, is based on the Venturi principle which allows the wind in a funnel-shaped air inlet to accelerate. Meanwhile, the large-scale vortices and associated turbulent kinetic energy in the tube are diminished through the inlet honeycomb grid, thus driving the multi-turbines in tandem to generate more power. Second, to verify the efficiency of this concept, the CFD simulation technology is employed to investigate the wake characteristics in two distinct flow fields, namely the open space and the vortex tube space. The simulation results are then compared with prototype site tests. The comparison confirms the superior performance of this vortex tube scheme accommodating multi-turbines and the use of a honeycomb at the inlet.
Optimization Method of Photovoltaic Microgrid Energy Storage System Based on Price-based DR
Authors: Li Jiayu , Dang Bin , Miao Guixi , Wang Xin , Yuan Liang , Xi Shengzhe
Published: September 2023

Extreme events lead to an increasing number of power outages in the distribution network. It is currently the most effective method to restore power supply after distribution network failure to connect distributed photovoltaic to the distribution network in the form of microgrids. However, the randomness of distributed PV output and load is the biggest obstacle limiting its development. Therefore, an optimization method of photovoltaic microgrid energy storage system (ESS) based on price-based demand response (DR) is proposed in this paper. Firstly, based on the influence of the uncertainty of the time of use (TOU) and load on the price-based DR, a price-based DR model is built. Then, taking the minimum difference between photovoltaic output and load demand as the optimization objective, the optimal operation model of price-based DR based on the fuzzy chance constrained program (FCCP) is established, and an optimization model of photovoltaic microgrid ESS based on FCCP is obtained. Finally, the fuzzy chance optimization problem is converted into a deterministic optimization problem through constraint equivalent treatment. The proposed method is verified by numerical simulations.
Analytical Calculation of Hybrid Excitation Transverse Flux Permanent Magnet Synchronous Linear Motor Based on Schwarz–Christoffel Mapping
Authors: Zhang He , Liu Hao , Sun Chao
Published: September 2023

An analytical calculation method of thrust and suspension force based on Schwarz–Christoffel (SC) mapping is presented for hybrid excitation transverse flux permanent magnet synchronous linear motor (HETFPMSLM) applied to a maglev train. The effectiveness of the analytical calculation is verified by three-dimensional finite element analysis. Firstly, the structure and principle of HETFPMSLM are analyzed, and its longitudinal two-dimensional SC mapping model is proposed. The magnetic field of HETFPMSLM is calculated by MATLAB’s SC Toolbox. Then the suspension force and thrust are calculated by the Maxwell stress tensor method, which is compared with the 3D finite element to verify the accuracy of the analytical calculation.
Thermal Analysis and Optimization of Energy Storage Battery Box Based on Air Cooling
Authors: Wang Lulu
Published: September 2023

For energy storage batteries, thermal management plays an important role in effectively intervening in the safety evolution and reducing the risk of thermal runaway. Because of simple structure, low cost, and high reliability, air cooling is the preferred solution for the thermal management. Based on a 50 MW/100 MW energy storage power station, this paper carries out thermal simulation analysis and research on the problems of aggravated cell inconsistency and high energy consumption caused by the current rough air-cooling design and proposes the optimal air-cooling design scheme of the energy storage battery box, which makes the structure of battery module more reasonable and the temperature distribution between the batteries more uniform. It has a certain guiding significance for energy saving, consumption reduction, and stable operation of energy storage systems.
Research on Control Strategy of Hybrid Energy Storage System Participating in Primary Frequency Regulation of Power Grid
Authors: Wei Ning , Yan Xin , Han Xinglei , Ma Xiaolu , Cui Jian , Sun Weitao
Published: September 2023

With the ongoing development of China’s power system, there is a gradual increase in the proportion of new energy power generation. However, the randomness and volatility associated with new energy power generation can lead to increased frequency fluctuations in the power grid, posing a significant challenge to power system frequency regulation. In this paper, we investigate the control strategy of a hybrid energy storage system (HESS) that participates in the primary frequency modulation of the system. We analyze the advantages and disadvantages of various types of new energy storage from both technical and economic perspectives and perform an applicability analysis system to select lithium batteries and supercapacitor energy storage for forming a HESS. We propose a virtual droop control strategy to regulate the output of the HESS in the primary frequency regulation of the system. Finally, we build a simulation model that includes the HESS and power grid on the MATLAB/Simulink simulation platform and conduct a simulation analysis. The results show that the proposed strategy is superior and effective in controlling the HESS’s output when participating in the primary frequency modulation of the system.
Wide frequency band oscillation mechanism and suppression measures for grid-interfaced PV inverters based on impedance analysis
Authors: Zhao Chaofan , Chen Laijun , Su Xiaoling , Yang Jun , Kang Pengpeng
Published: September 2023

With the rapid development of PV and wind power, the energy structure of the power grid is changing dramatically. The dominant power supply role played by conventional power sources such as hydropower and thermal power is gradually replaced by PV and wind power. All the power electronics-based equipment makes the power system stable form more complex, and one of the most significant challenges is wide frequency band oscillation (WFBO). This paper proposes an impedance analysis method for PV inverters in high proportion to new energy-integrated power systems. First, we investigate WFBO mechanism caused by the PV inverter based on its impedance model, and then a detailed impedance model of parallel PV inverters is developed to study WFBOs in PV stations. Finally, the WFBO suppression measure based on active damping control is proposed. Simulation results prove the correctness and feasibility of the active damping control strategy.
A study of the impact of voltage sag on sensitive loads at low-voltage distribution areas
Authors: Xu Tao , Yang Junqian , Wang Wei , Chen Jiong , Zhang Wen , Jiang Yihao , Zheng Xinying , Wang Qianggang
Published: September 2023

Under the background of the dual carbon goal and the new power system, the power system becomes more complex and diverse, and voltage sag events caused by short-circuit faults, overloads, switching operations, large motor starting, and distributed generation access are more frequent. On the other hand, with the increasing sensitivity of low-voltage distribution network electrical equipment to power quality, especially for precision process control equipment using computers, power electronics, and automation technology, new energy generating units, and electric vehicle charging facilities, voltage sag accidents will cause difficult-to-estimate losses in equipment production and operation, and frequent voltage sag events have become one of the main power quality problems affecting reliable power supply and normal equipment operation. To address this problem, this paper analyzes the impact of voltage sag on low-voltage substation loads from a mechanism perspective, establishes a voltage sag tolerance curve for electronic appliances through experimental research, and simulates and verifies the effectiveness and correctness of the method in this paper using a 3 MW-rated induction generator connected to the distribution network as an example.
Short-Term Load Forecasting Based on Improved VMD and KELM
Authors: Liu Liyuan , Zhou Bonan , Wang Yongqian , Luo Xianjue
Published: September 2023

To address the problem of low accuracy of short-term load prediction in the past, this thesis uses a prediction model with neural network LSTM as the main body and constructs an adaptive and dynamically adjusted rolling load prediction model to meet our load prediction needs through VMD decomposition, kernel limit learning machine, and correlation analysis techniques. To reduce the maximum load error and the overall result error, a correction algorithm is proposed to improve the VMD to minimize the impact of load decomposition; after that, the model is used to analyze a load of a day in a region to verify the superiority of the prediction model. The example shows that the load forecasting method can help to make more accurate predictions of short-term loads.
Study on Compression Ratio Optimization of M100 Methanol Engine
Authors: Chen Chen , Han Dong , Ma Zhicheng
Published: September 2023

A turbocharged and intercooled diesel engine was transformed into an ignited M100 methanol engine by adding a spark plug to the cylinder head. A one-dimensional model of the methanol fuel engine was established using the bench test data as the boundary conditions, and the accuracy and accuracy of the model were verified. Methanol has better octane number and explosion resistance than traditional fuels, increasing the compression ratio of the engine will improve the power and fuel efficiency of the methanol engine. Based on the original compression ratio of 12, 8 compression ratio simulation schemes were selected, including 11.4, 11.7, 12, 12.3, 12.6, 12.9, 13.2, 13.5, etc., and the engine performance and the combustion state in the cylinder changed with the compression ratio were analyzed by simulation calculation, and the engine was optimized and improved. The results show that when the engine compression ratio reaches 12.9, the engine performance reaches the optimal value.
Key technologies research and application of green power traceability based on blockchain
Authors: Wen Tingting , Li Da , Duan Tingting , Guo Qinglei , Zhao Lihua
Published: September 2023

Green power traceability is a crucial link to ensure the green power transactions’ authenticity, effectiveness and credibility. It’s an essential means to promote the large-scale development of green power. However, there are many links in the whole chain of green power. The data involves multiple departments and institutions. So it is not easy to trace the authenticity. This paper first introduces the entire chain of green power traceability and critical information. Secondly, it proposes the green power traceability scheme and key technologies. Then, it designs the system and functional architecture of green power traceability based on blockchain. Finally, it analyses the application effect of the system in green power trading and the Winter Olympics. This research provides the technical reference for the authenticity and traceability of green power. It helps the green-low-carbon transformation of energy consumption structure.
Cascaded H-bridge Type Power Electronic Transformer Electromagnetic Interference Study Based on Parallel Simulation
Authors: Sun Haifeng , Liu Xiaopeng
Published: September 2023

Power electronic converter (Power Electronic Transformer, PET) is widely used in power systems, so the research on PET electromagnetic disturbance (Electro Magnetic Interference, EMI) cannot be ignored. PET consists of many insulated gate bipolar transistors (Insulate-Gate Bipolar Transistor, IGBT). A large number of converter levels will cause problems such as small simulation steps and long simulation times. To solve the above problems, firstly, the IGBT and its anti-parallel diodes are modeled by an 8-node model to reduce the complexity of the system; secondly, after dividing the model into fine-grained models, CUDAC coding is used to realize the parallel operation of the system on the graphics processing unit (Graphics Processing Units, GPU). Finally, the feasibility of the proposed method is compared with the PSCAD simulation results.
Influence of Large-scale Distributed Photovoltaic Access on Harmonic Characteristics of Distribution Network
Authors: Hong Xiaoai , Tian Lijun , Yin Xunpeng , Xu Minghua , Han Lei , Liu Xingjian
Published: September 2023

With the development of PV on a large scale, developable rooftop distributed PV becomes a high-quality resource to achieve the double carbon goal. Compared with single-node and low-permeability PV access, large-scale photovoltaic access makes the power grid present high-power electronic characteristics, which has a more complex impact on the harmonic characteristics of the distribution grid. To comprehensively reveal the influence of large-scale distributed photovoltaic access on the harmonicity of the distribution network, this paper first conducts a theoretical analysis of the harmonic generation mechanism. On this basis, build a simulation model based on Matlab/Simulink, considering the measurement indexes of low harmonics and supraharmonics, and the influence of grid-connected location, grid-connected capacity, background harmonics, access mode, and other factors on the harmonic characteristics of the distribution network is simulated and analysed. According to the simulation results, large-scale distributed PV access significantly increases the content of low and supraharmonics in the distribution network, which has a great impact on the harmonic characteristics of the distribution network.
Analysis Method for Photovoltaic Absorption Capacity of Distribution Network Based on Risk Quantification and Network Reconstruction
Authors: Xue Guiting , Zhang Bowen , Zhao Yuan , Qi Hong , Liu Kaixin , Yang Xuetao , Xiao Xiangtao
Published: September 2023

The random characteristics of photovoltaic (PV) power will cause changes in node voltage and line power, which is an important factor affecting the photovoltaic absorption capacity of the distribution network (DN). So as to accurately evaluate the impact of photovoltaic randomness on the absorption capacity of DN, an analysis method of photovoltaic absorption capacity of DN is proposed based on risk quantification. Firstly, a photovoltaic absorption capacity evaluation model is proposed based on risk quantification, which considers the randomness of load and PV power and can improve the accuracy of photovoltaic absorption capacity assessment. Secondly, the photovoltaic absorption capacity DN is calculated with the network topology and photovoltaic access capacity of the DN as the optimization variables. The probabilistic power flow is performed by linear power flow, which effectively improves the calculation speed. Finally, the proposed PV absorption capacity analysis method is simulated and analyzed. The simulation results show that the proposed method can effectively take into account the impact of load and photovoltaic randomness and improve the photovoltaic absorption capacity of DN.
Application of Gray Wolf Optimization Algorithm in Urban Electricity Load Forecasting Model
Authors: Tian Hailin , Wang Fang
Published: September 2023

A combined prediction model based on long short-term memory neural network (LSTM) and convolutional neural network (CNN) is proposed in order to increase the prediction accuracy of short-term load. To address the issue that the gray wolf optimization (GWO) search process is prone to falling into local optimum. An improved grey wolf algorithm (IGWO) is proposed to update the convergence factor using the lower incomplete gamma function to improve the global optimization performance. The Dropout technique is used to improve the generalization ability of the model; the network layers are improved by increasing the initialization of weights; the model is trained using an adaptive moment estimation (Adam) optimizer, test data are input to the trained neural network model, and finally, the optimized model is used for prediction. The high prediction accuracy of the proposed method is demonstrated experimentally.
Research on Multi-carrier PWM Technology Based on Modular Multilevel Inverter
Authors: Guo Yifeng , Shi Qingyu , Huang Limin , Guo Shicheng , Zhang Li , Fan Dakun
Published: September 2023

The modular multilevel inverter circuit structure is introduced, three traditional multi-carrier PWM modulation strategies for modular multilevel inverter circuits are studied and analyzed, and the inverter-side output voltage spectrum is analyzed by simulation. Based on the traditional multi-carrier PWM modulation strategy, this paper uses the PWM technology combining multi-reference wave and multi-carrier to analyze and simulate, and builds a modulation model and a circuit model of the modular multilevel inverter circuit in the Matlab/Simulink environment. Compared with the simulation results of the traditional multi-carrier PWM strategy, the multi-carrier modulation algorithm of the multi-reference wave can slightly reduce the total harmonic distortion rate. At the same time, the multi-carrier modulation algorithm of multiple reference waves can ensure that the capacitor voltage values of each submodule of the modular multilevel inverter circuit are equal so that there is no circulation phenomenon between each phase. Finally, a physical platform is built to verify the authenticity of the simulation experiment.
Topology of Wind Power DC Collection Converter Based on Double Bus Structure and Its Power Balancing Control Strategy
Authors: Lu Yajun , Zhong Qidi , Wang Shuai , Liu lin , Sun Jinping
Published: September 2023

Wind power collection technology is the key to grid-connected wind power generation. Compared with AC wind integration, DC wind power collection is more advantageous. Using a triple active bridge (TAB) converter as a submodule, this paper proposes a wind power DC converter topology and its control strategy for medium-voltage dc (MVDC) grid connection. The converter adopts a double bus structure, with the MVDC bus connected to the grid and the low-voltage dc (LVDC) bus handling the mismatched power. It has independent maximum power point tracking (MPPT) control, power balancing, and autonomous voltage balancing on the output side. The converter system is simulated and verified on the MATLAB/SIMULINK software platform. The simulation results show the effectiveness of the control strategy and the ability of the converter to operate stably under multiple conditions.
Automatic generation method of power grid maintenance operation ticket based on GA-ANN optimization algorithm
Authors: Chen Zhangguo , Hu Chao , Qiao Zhizhong
Published: September 2023

The automatic generation method of power grid maintenance operation ticket based on the GA-ANN optimization algorithm is designed. An automatic generation model of power grid maintenance operation ticket, including data communication, power grid information topology, task planning, path search, path selection, operation ticket generation and simulation of rehearsal agent, is built. This paper takes the operation sequence generated by different equipment performing operation tasks as the training sample of the GA-ANN model, obtains the change rule of operation sequence of each equipment agent, and realizes the automatic generation of maintenance operation tickets for different equipment. It is verified by experiments that the time of automatic generation of operation tickets is fast and can complete the maintenance and invoicing of various equipment.
Research on the operation control strategy of optical storage and DC microgrid
Authors: Wu Jinming , Xu Aoran , Peng Ye , Zhang Xiaotong , Li Zezheng , Feng Yuexin
Published: September 2023

Compared to traditional alternating current (AC) power grids, direct current (DC) microgrids have outstanding technical and economic advantages and bear great development potential and application value. In this paper, the operation control strategy of optical storage DC microgrid is studied. Firstly, the structural composition and related characteristics of the DC microgrid are systematically analyzed. Secondly, the coordinated control strategy for the DC microgrid during off-grid operation, grid connection operation, and load optimization is studied, and the mathematical model of the DC microgrid is established. Finally, the simulation analysis of the model of the DC microgrid is conducted, and the results show that the coordinated control strategy can effectively stabilize the output power, promote the power balance of the power grid, and provide fundamental guidance and reference for the efficient conversion and control of power grid, which has important practical significance.
Adopting multiple vision transformer layers for fine-grained image representation
Authors: Sun Fayou , Ngo Hea Choon , Yu Yelan , Xiao Zhengyu , Meng Zuqiang
Published: September 2023

Accurate discriminative regions proposal has an important effect for fine-grained image recognition. The vision transformer (ViT) brings about a striking effect in computer vision duo to its innate muti-head self-attention mechanism. However, the attention maps are gradually similar after certain layers and since ViT adds classification token for perform classification, it is unable to effectively select discriminative image patches for fine-grained image classification. To accurately detect discriminative regions, we propose a novel network AMTrans, which efficiently increases layers to learn diverse features and utilizes integrated raw attention maps to capture more salient feature. Specifically, we employ DeepViT as backbone to solve the attention collapse issue. Then, we fuse each head attention weight within each layer to produce attention weight map. After that, we alternatively use recurrent residual refinement blocks to promote salient feature detection and then utilize semantic grouping method to propose the discriminative feature region. A lot of experiments prove that AMTrans acquires the SOTA performance on three widely used fine-grained datasets under the same settings, involving Stanford-Cars, Stanford-Dogs and CUB-200-2011.
Optimization of ICANet lightweight human pose estimation based on HRNet
Authors: Hou Qing , Li Kun , Xu Zhen
Published: September 2023

The existing high-resolution human pose estimation models have low applicability in practical applications due to their large parameter quantity and high computational complexity. To address these issues, this paper proposes a human pose estimation network with a lightweight inverted residual coordinate attention network (ICANet) based on the high-resolution network (HRNet). With the introduction of CoordAttention mechanism and the inverted residual module, this paper proposes two lightweight network modules, namely ICAneck and ICAblock, which not only reduce model parameter quantity and computational complexity, but also achieve feature enhancement of long-range dependence and precise position information in spatial directions of the feature map. Experimental results show that compared to HRNet, the ICANet model proposed in this paper reduces its parameter quantity by 53.7% and computational complexity by 32.4% on the COCO validation set, and lowers its parameter amount by 53.7% and computational complexity by 32.6% on the MPII validation set. Practical applications prove that ICANet still achieves high-precision detection of human key points with fewer parameters and lower computational complexity, and has higher applicability and practicality compared with common human pose estimation networks such as the Stacked Hourglass Network (Hourglass), Cascaded Pyramid Network (CPN), and SimpleBaseline, and therefore has better applicability and practicality.
Comparative evaluation for alternative variable importance rankings for pedestrian injury severities
Authors: Cheng Yichi , Zhang Yongping
Published: September 2023

Little research is dedicated to evaluating the performance difference of various metrics in ranking predictor importance in the traffic safety field. To this end, the main objective of the current paper is to evaluate and quantify different methods for sorting the variable importance related to crash severity. A comprehensive database for pedestrian-related crashes in the state of California was developed. Four popular measurement metrics used in the past were chosen for evaluation purpose: Mean Decrease Accuracy (MDA), Mean Decrease Gini (MDG), log-likelihood ratio test associated with multinomial logit model, and Principal Component Analysis (PCA). The former two metrics come under the same umbrella of the Random Forest (RF) technique, while the latter two are methods belonging to different domains. The results show the alternative methods yield different variable importance rankings with PCA being isolated from others. The two methods under the same domain of the random forest, or MDG and MDA, have the most common results, but still reveal a 17% ranking difference. It is anticipated that the results could raise more awareness of the importance of selecting the appropriate metrics to evaluate the predictor importance from different perspectives.
Monte Carlo simulations of LUOSHU: a new 46-meter small-angle neutron scattering instrument in China
Authors: Tang Y.F. , Zhong S.Y. , Yan G.Y. , Chen J.
Published: September 2023

The LUOSHU small-angle neutron scattering spectrometer is one of the neutron scattering instruments under construction at China Mianyang Research Reactor. Quantitative characterization of nanoparticles is now in a higher demand for research interests in material science, physics, chemistry, biology. Therefore, as a general-purpose small-angle scattering spectrometer, LUOSHU is aimed to provide a large accessible Q range, flexible resolution and sufficient neutron flux. Monte Carlo simulations have been performed on LUOSHU from the neutron source to sample platform to optimize the parameters of the bender part, collimation system, and the velocity selector. And the instrument layout is optimized base on the simulation results. Finally, the maximum neutron intensity of the neutron beam at the sample stage can reach 1.01 × 107 N·s-1·cm-2 and its divergence is 0.63.
Time and Energy Resolving Time-over-Threshold ASIC for MPPC module in TOF-PET system (ToT-ASIC2)
Authors: Orita T. , Uenomachi M. , Shimazoe K. , Ikeda H.
Published: September 2023

ToT-ASIC2 is a new custom front-end application specific
integrated circuit (ASIC) to readout silicon photomultiplier (SiPM)
and multi-pixel photon counter (MPPC) for time-of-flight positron
emission tomography (ToF-PET). ToT-ASIC2 is a 64-channel ASIC
fabricated using a commercial 0.25 μm CMOS process. Each
channel has an input-current buffer that sends signals to the SLOW
and FAST paths, which are used for incident radiation energy and
timing information, respectively. Time-over-Threshold (ToT) signals
from these paths are combined into one ToT signal to be output
outside the ASIC. The power consumption is approximately 2.9 mW per
channel.

This study developed a detection system comprising an MPPC with
coupled GAGG pixelated scintillators, a front-end board with
ToT-ASIC2 and ToT-DAQ. Consequently, energy and timing measurement
experiments were performed using this system to confirm the
ToT-ASIC2 energy- and timing-resolving capability. Prototype
positron emission tomography experiments with 22Na indicated an
energy resolution of 6.7% for 511 keV with the coincidence timing
resolution being 215 ps.
Investigating whether the inclusion of humid heat metrics improves estimates of AC penetration rates: a case study of Southern California
Authors: Peplinski McKenna , Kalmus Peter , Sanders Kelly T
Published: September 2023

Global cooling capacity is expected to triple by 2050, as rising temperatures and humidity levels intensify the heat stress that populations experience. Although air conditioning (AC) is a key adaptation tool for reducing exposure to extreme heat, we currently have a limited understanding of patterns of AC ownership. Developing high resolution estimates of AC ownership is critical for identifying communities vulnerable to extreme heat and for informing future electricity system investments as increases in cooling demand will exacerbate strain placed on aging power systems. In this study, we utilize a segmented linear regression model to identify AC ownership across Southern California by investigating the relationship between daily household electricity usage and a variety of humid heat metrics (HHMs) for ~160000 homes. We hypothesize that AC penetration rate estimates, i.e. the percentage of homes in a defined area that have AC, can be improved by considering indices that incorporate humidity as well as temperature. We run the model for each household with each unique heat metric for the years 2015 and 2016 and compare differences in AC ownership estimates at the census tract level. In total, 81% of the households were identified as having AC by at least one heat metric while 69% of the homes were determined to have AC with a consensus across all five of the heat metrics. Regression results also showed that the r
2 values for the dry bulb temperature (DBT) (0.39) regression were either comparable to or higher than the r
2 values for HHMs (0.15–0.40). Our results suggest that using a combination of heat metrics can increase confidence in AC penetration rate estimates, but using DBT alone produces similar estimates to other HHMs, which are often more difficult to access, individually. Future work should investigate these results in regions with high humidity.
The role of eddy-wind interaction in the eddy kinetic energy budget of the Agulhas retroflection region
Authors: Zhu Yanan , Li Yuanlong , Yang Yang , Wang Fan
Published: September 2023

The Agulhas retroflection (AR) region possesses the highest eddy kinetic energy (EKE) level in the Indian Ocean. However, mechanisms regulating EKE of the AR remain uncertain. Here, by analyzing an eddy-resolving coupled model simulation with improved EKE representation, we show that the upper-ocean EKE of the AR is mainly generated through barotropic instability in its upstream and leakage zones and is by nonlocal transport in its downstream zone. The interaction between mesoscale eddies and local winds plays a key role in EKE dissipation. The lack of eddy-wind interaction results in flawed EKE budget in the leakage zone in ocean-alone models, leading to severe biases in EKE distribution with overestimation and over-strong penetration into the South Atlantic. Our results highlight the essence of mesoscale air-sea interaction in the dynamics of the AR, with implications for understanding the inter-basin transport of the Agulhas leakage.
Uncertainty relation for non-Hermitian operators
Authors: Bagarello F
Published: September 2023

In this paper we discuss some aspects of the Heisenberg uncertainty relation, mostly from the point of view of non self-adjoint operators. Some equivalence results, and some refinements of the inequality, are deduced, and some relevant examples are discussed. We also begin a sort of dynamical analysis of the relation, in connection with what has been recently called γ-dynamics and γ-symmetries, and we discuss in some details the role of different scalar products in our analysis. The case of self-adjoint operators is recovered as a special case of our general settings.
The heat kernel of the asymmetric quantum Rabi model
Authors: Reyes-Bustos Cid
Published: September 2023

In this paper we derive an explicit formula for the heat kernel of the asymmetric quantum Rabi model, a symmetry breaking generalization of the quantum Rabi model (QRM). The method described here is the extension of a recently developed method for the heat kernel of the QRM that uses the Trotter–Kato product formula instead of path integrals or stochastic methods. In addition to the heat kernel formula, we give applications including the explicit formula for the partition function and the Weyl law for the distribution of the eigenvalues, obtained from the corresponding spectral zeta function.
Route optimization model design to support multi-cluster commodity distribution in the Moluccas islands
Authors: Afifudin M T , Sahar D P , Muspida  , Faisal M , Loppies L R , Indah A B R
Published: September 2023

This study aims to design a route optimization model to support commodity distribution in the Moluccas archipelago zone. The model is designed using an integer programming approach for multi-depot multi-cluster with the aim of minimizing distance. In this case, several points on the island must be serviced. Each service point will only choose one port to serve. Sea transportation routes are formed from selected port nodes with a ring-ring-star hierarchical structure. A model designed to complement transportation routes in meeting the demand for service points by considering local, regional and global route distribution. Each level route will select one or more depots which will represent set to the top route level. The model is applied to several scenarios to see the best distance recommendations from island sample characteristics and point and island sizes.
The effect of stabilizer type on the stability of snakehead fish (Channa striata) extract dispersion
Authors: Irwan  , Tawali A B , Rusdin I , Sulaiman M R R A
Published: September 2023

Snakehead fish (Channa striata) extract in the form of dispersion is one of the innovations in the development of snakehead fish products. Snakehead fish extract dispersion is a product in the form of a mixture of syrup (dispersion) made from snakehead fish extract raw materials, honey, and other additives. However, the syrup/dispersion products produced in previous studies have not been completely stable. This is indicated by the presence of precipitation during dispersion storage. Therefore, it is necessary to choose the right type of stabilizer to overcome this. The aims of this study were to obtain the best stabilizer for producing a stable snakehead fish extract dispersion. The method in this study was to make a dispersion of snakehead fish extract with three different stabilizers, namely xanthan gum (0.3%), carrageenan (0.1%), and carboxymethyl cellulose (CMC) (0.6%). Then we analyzed the viscosity, phase separation ratio, and redispersibility. The results showed that xanthan gum has a better level of stability than carrageenan and CMC, with a viscosity value after storage of 1, 3, 5, and 7 days, respectively 53.97 mPa.s, 51.67 mPa.s, 51.50 mPa.s, and 51.17 mPa.s. While the viscosity value of carrageenan during storage is 1, 3, 5, 7 days, respectively 5.27 mPa.s, 5.20 mPa.s, 4.90 mPa.s, and 4.50 mPa.s, and storage of CMC 1, 3, 5, and 7 days, respectively 642.67 mPa.s, 505.33 mPa.s, 452.00 mPa.s, and 297.33 mPa.s. The results of the phase separation ratio analysis showed that the stabilizers xanthan gum and CMC did not experience phase separation during storage for 1, 3, 5, and 7 days. Meanwhile, the carrageenan stabilizer at storage 1, 3, 5, and 7 days has a successive phase separation ratio of 43.81%, 40.34%, 39.47%, and 39.47%. The results of the redispersibility analysis showed that the CMC stabilizer and xanthan gum were not redispersible during storage 1, 3, 5, and 7 days. While the carrageenan stabilizer has the same redispersibility value during storage 1, 3, 5, and 7 days is one time shuffling.
Strategies for developing extension worker’s performance during the covid-19 pandemic in Bulukumba Regency
Authors: Jamil M H , Rukka R M , Sulaiman A , Viantika N M , Anisa A
Published: September 2023

Extension activities in Indonesia and even the world have experienced many changes since the outbreak of the Covid-19 virus pandemic. This study aims to formulate a strategy for developing extension workers performance that can be applied during the Covid-19 pandemic in Bulukumba Regency. Descriptive qualitative method with analysis SWOT applied. The results of this study show the effectiveness of individual face-to-face communication and communication with cellular telephone media, increasing the competence of extension workers in terms of information technology and communication, the assimilation of supporting facilities and infrastructure in the form of telecommunications devices (computers/laptops and internet quotas, including the improvement of an internet connection system that is evenly distributed throughout the region and p Social network strengthen and trust between extension workers, farmers, and other stakeholders is an important strategy to implement to develop the performance of extension workers in the Covid-19.
Indonesian consumers’ willingness to pay for organic coffee
Authors: Khaliqi M , Ramadhani Ariella , Pane T C , Sinaga F H , Darmansyah D , Sari I R M
Published: September 2023

The use of organic certification benefits farmers as well as the environment. Organic coffee farmers, on the other hand, face the challenge of determining how much consumers are willing to pay for the organic coffee they produce. The purpose of this study was to investigate the factors that influence Indonesian consumers’ willingness to pay for organic coffee, as one of the indicators that influence consumer purchasing decision behavior. A structural equation model analysis was used to collect data by distributing questionnaires to a total of 766 respondents. The model was created by combining variables from the Theory of Planned Behavior and consumer awareness. This study was successful in demonstrating the direct impact of attitude, subjective norms, PBC, and consumer awareness on consumers’ willingness to pay for Indonesian organic coffee. On the other hand, health and environmental sustainability factors had an indirect influence on consumers’ willingness to pay for organic coffee. Meanwhile, regional development factors had no effect on consumers’ willingness to pay, either directly or indirectly.
Sago value chain analysis in Luwu and North Luwu District, South Sulawesi
Authors: Nisa’a Nursyami , Mahyuddin  , Syamsuri Prayudi
Published: September 2023

As the center of sago production, sago business in Luwu District and North Luwu District has long been the main livelihood of the local community. This study as a whole examines the linkage of the sago value chain with government intervention. The method of determining the location by purposive sampling with the consideration that Luwu District and North Luwu District are the center of sago production in South Sulawesi. The analytical method used for value chain research is chain analysis with value chain mapping from ACIAR (2012) and qualitative descriptive analysis, namely content analysis and thematic analysis. The sago value chain in Luwu District and North Luwu District involves various actors, such as farmers/producers, collectors, and retailers in the sago production and distribution process. Government intervention in this study included providing training and procurement of equipment to sago farmers. The results of this study show that government intervention only focuses on reducing the workload of sago farmers. Government intervention in this study does not directly impact other sago value chain actors, but reducing farmers’ workload can potentially have an overall positive effect by increasing the availability of sago raw materials they obtain from farmers.
Comparative analysis of profitability of catfish business using conventional and biofloc systems in Maros District
Authors: Augustiawan  , Rukman Didi , Rahmadanih
Published: September 2023

Maros Regency is one of the coastal and marine areas that has the potential to develop large inland and marine fisheries in South Sulawesi. Catfish is a freshwater fish that has economic value. This research aims to analyze the profitability of the catfish business in Turikale District and Mandai District, Maros Regency using conventional and biofloc methods. This research method uses the quantitative analysis method with the location chosen deliberately, namely Turikale and Mandai Districts. Sampling was carried out using snowball sampling. Data collection techniques using interview techniques. Data analysis using qualitative and quantitative analysis. The results of the research are the total profits obtained by catfish farming with conventional techniques in the Mandai and Turikale Districts of IDR 10,493 and 854.71/harvest profits for conventional techniques of IDR 4,669,332.40 and for the Biofloc technique. IDR 5,824,522.31 which means the advantage of the biofloc technique is greater than conventional
Production and chemical quality of sweet corn with single fertilizer combination (SFC) on upland in West Papua
Authors: Jambang N , Hakim L , S Witman , I A Sunante
Published: September 2023

Sweet corn is popular in West Papua. This study was aimed at determining the production and chemical qualities of sweet corns using single fertilizer combination (SFC). A completely randomized design experiment was used with 5 treatments and 3 replications. The treatments were without fertilization (P0), with a concentration of P1 (22.4g/plant); P2 (23.52/plant); P3 (24.64g/plant); P4 (25.76g/plant). Variables observed were weight, length, diameter, pH, water, ash and fat content. The data obtained were analysed using analysis of variance continued with the Honest Significant Difference Test. Results showed that different concentrations gave a very significant difference (P<0.01) on cob weights (gr) (P0, P1, P2, P3, P4 were 51.39; 115.40; 133.06), cob lengths (mm) (78.45; 107.37; 113.92; 131.54;141.02), and cob diameters (mm) (24.56; 31.22; 34.29; 36.21; 37.55); did not give a significant difference (P>0.05) on pH (5.47; 5.37; 5.41; 5.40; 5.38), moisture content (%) (60.41; 60.75; 60.29; 60.08; 60.08), ash content (%) (1.95; 2.07; 2.05; 1.96; 1.92), and fat content (%) (0.62; 0.53; 0.43; 0.52; 0.40). The conclusion was that different concentrations of SFC did not give a different effect on pH, water, ash, fat content and gave a very significant difference effect on weight, length, diameter of sweet corn cobs.
A meta-analysis of the effects of gamma irradiation on biochemical and physical characteristics of honey
Authors: Ujilestari T , Damayanti E , Sholikin M M , Febrisiantosa A , Permadi S N , Ivanti L , Jayanegara A , Wahyono T
Published: September 2023

Gamma irradiation can be used to sterilize honey products. Many previous reports related to biochemical, physical characteristics and antibacterial activity on irradiated honey have not been combined into one quantitative report. Therefore, this study was conducted to determine the effects of gamma irradiation on biochemical and physical characteristics of honey. The source of data in meta-analysis study was conducted on search engines (Scopus®, PubMed®, and Google scholar®), searched with “irradiation”, “gamma”, and “honey” as keywords. Data on gamma irradiation dosage and characteristics of honey were extracted from 12 articles and 44 studies (control vs. irradiated honey). The meta-analysis results showed that gamma irradiation reduced moisture content (p < 0.01). However, gamma irradiation had no effect on viscosity, sugars, total soluble solids, and ash content. It is interesting to note that gamma irradiation significantly increased flavonoid and phenolic compounds (p < 0.01). Gamma irradiation also reduced the level of microorganism in honey (p < 0.01), as reported in total aerobic plate count variable. In summary, except for moisture and vitamin C, gamma irradiation did not influence biochemical characteristics of honey. Gamma irradiation also had no effect on viscosity as physical parameters.
Grain color measurement and nutrient content of local pigmented rice from South Sulawesi
Authors: Manwan Sri W , Hanifa Arini P , Dewayani W , Suriany  , Ardah M I
Published: September 2023

This study is aimed at measuring the color and nutrient contents of local pigmented rice from South Sulawesi. Five grams of husked rice grains are placed on a 60 mm petri dish before attaching the TES 135 colorimeter. Total protein content was measured using the Kjeldahl method. Total fat content was measured using Soxhlet. Selected varieties were analyzed further for zinc (Zn) and iron (Fe) content using Atomic Absorption. Spectroscopy. Data were analyzed using a one-way ANOVA, followed by the Duncan Multiple Range Test at 5%. The results showed that the Le’leng variety showed the lowest values of L*, a*, and b*, which means that it has the darkest color. The highest protein content is found in Le’leng and Kobo. The protein content of local pigmented rice is higher but tends to be similar in fat content to modern rice. It can be concluded that colorimetry grain color measurement follows the grains’ visual appearance. The darker the grain color, the lower the L*, a*, and b* parameters. Local pigmented rice from South Sulawesi has significant protein, fat, Fe, and Zn. Color appearance can be a preliminary visual indicator of the bioavailability of compounds with health benefits in pigmented rice..