bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Sparse Terahertz Synthetic Aperture Imaging Algorithm
Authors: Wang Ningbo , Qi Feng
Published: June 2023

For the terahertz synthetic aperture near-field imaging problem, this paper proposes a SAR imaging method based on sparse reconstruction, which solves the problems of slow scanning speed, a large amount of data, and complicated calculations in the terahertz synthetic aperture imaging process. The targets in space are sparsely sampled and reconstructed using a compressed sensing reconstruction method. Simulation results show that high-quality target reconstruction can be achieved at low sampling conditions.
Pre-control of shell expansion fracture process by high energy beam
Authors: Xin Bi Wei , Bing Li Wei , Luo Yu Song , Xin Yu Jia , Bin Li Wen , Wang Xiao Ming
Published: June 2023

Aiming at the dynamic deformation and fracture response of high-energy precontrolled shell under high strain rate,the expansion and fracture process of 40CrMnSiB steel precontrolled shell was studied by numerical modeling and experiment.The results show that:In detonation loading condition,the high energy beam precontrol shell expansion fracture process can be divided into three stages of free expansion,precontrol fracture and matrix fracture.Firstly, the brittle fracture occurs in the fusion region, and the crack starts at the bottom of the cavity region and propagates along the fusion region to the outer wall of the shell. After the brittle fracture is completed, the adiabatic shear fracture occurs in the matrix, and the normal line between the fracture surface and the inner wall of the fragment is 45 °.The recovered fragment shape is in the shape of precontrolled quadpyramid,and the fragment quality is concentrated in the precontrol area. the fragment dispersion has a good distribution law,which better verifies the pre-control effect of high-energy beam pre-control technology on the fragment shape and the direction of dispersion,and provides technical reference for further optimization of high-energy beam pre-control warhead structure.
Ignition sensitivity and flame propagation of titanium powder cloud
Authors: Wang Y X , Zheng C , Han J L , Huang W M , Zhang Q X , Zhao J B , Wang X , Chen X H , Yang X Y
Published: June 2023

The ignition sensitivity and flame propagation of titanium dust cloud were investigated to evaluate the risk of combustion and explosion of titanium powder. The minimum ignition temperature(MIT) was determined by Godbert-Greenwald furnace and the minimum ignition energy(MIE) was determined by Hartmann apparatus. The flame propagation behavior in the Hartmann apparatus was recorded by high-speed camera and infrared thermal imager. The results show that the spherical titanium powder with a median diameter of 12.5μm had a minimum ignition temperature of 400°C, a minimum ignition energy of less than 1mJ, and a maximum flame temperature of 1666°C. The dust concentration had a greater influence on the minimum ignition temperature than the dispersion pressure, titanium dust cloud had high ignition sensitivity and fast flame propagation speed. The experimental results can provide a reliable basis for judging the explosive risk of titanium powder.
Study of armor-piercing self-sharpening properties of 88WC-12Co material
Authors: Yin G X , Zhang Q , Chen P , Hong B H , Jiang N , Gao D C
Published: June 2023

In this paper, the armor piercing power of 93W-4Ni-3Fe and 88WC-12Co with the same target velocity and core size is compared through experiments. The craters formed by the penetration of the same size projectile core made of 88WC-12Co and 93W-4Ni-3Fe into the semi-infinite Q235 steel target at the velocity of 1300 m/s–1500 m/s were compared. The penetration depth of 88WC-12Co is 12.5% –35% lower than that of 93W-4Ni-3Fe ( including residual projectile core ), and the pore size is about 12%–26% smaller. At the velocity of 1300 m/s-1480 m/s, there are more residual projectiles at the bottom of 93 W projectile pit. When the velocity is higher than 1510 m/s, the residue is less and the utilization rate of core material is higher. The aperture caused by the penetration of 88WC-12Co projectile core is slender and smooth, and the residual at the bottom of the crater is less than 93W. This proves that 88WC-12Co material has certain armor piercing self-sharpness. It is speculated that 88WC has a similar or even higher penetration ability to 93W when the initial kinetic energy of the two cores is the same.
Simulation and experimental study of fragment penetration into armored steel plate
Authors: Zhang Wen-juan , Yang Xu , Tan Kun , Zhang Cun-wang , Liu Zun-fei , Liu Hou-gang , Li Jun-lin
Published: June 2023

In order to study the penetration ability of fragment simulation projectile(FSP) to armored steel target, and to detect the protection ability of target plates with different thicknesses. Combined with numerical simulation and experiment, the penetration process of FSP on armored steel target plates with different thickness ratios is studied. The design and implementation preparations were made for the damage of the steel target plate by the fragments, and the relevant data were obtained and analyzed. The analysis results show that the finite element analysis and the experimental study are in good agreement, and the ballistic limit of armored steel targets with different thicknesses and the calculation formula of the residual velocity of the FSP are obtained. The research results provide the basis and support for the evaluation, design and improvement of armored vehicle protection capability.
Experimental investigation of blast resistance of steel structures with different elastomeric coatings subjected to underwater explosive loading
Authors: Dai Lihui , An Fengjiang , Wu Cheng
Published: June 2023

Elastomeric material is used as blast-resistant structure because of its good mechanical properties.A series of underwater near-field explosive tests at different standoff distances were conducted to investigate the anti-explosion performance of steel structures covered with rubber and polyurea coatings. The experimental results demonstrated that both rubber and polyurea could enhance the blast resistance of test plates, and the polyurea coating performed better in reducing the deformation of steel plate and damage of steel structure. Compared with rubber, the polyurea has excellent mechanisms of energy absorption and dissipation, its mechanical behavior and molecular structure of elastomeric material determines the different ways of energy absorption and dissipation.
Study on damage law of projectile charge penetrating three-layer steel plate
Authors: Qu kepeng , Hu Xueyao , Bi chao , Guo Xiang , Xiao Wei
Published: June 2023

Aiming at the problem that the projectile charge is easy to be damaged when penetrating multi-layer targets, which affects the safety of use, the light gas gun was used as the loading source to carry out the experiment of projectile penetration into single-layer, two-layer and three-layer 45# steel plates. The damage states of projectile charge were obtained by industrial CT technology. Combined with the numerical simulation results, the formation and evolution mechanism of projectile charge damage was analyzed. The results show that when the projectile charge penetrates the three-layer steel plate at an angle of 15 ° at the speed of 400m / s, the charge damage appears after penetrating the second layer steel plate, and mainly occurs at the tail of the charge. When penetrating the third layer steel plate, the damage expands along the axial and transverse direction; The tensile wave formed by the reflection of the free surface at the tail of the charge is the main reason for the formation of damage. The repeated action of compression and tension of the charge leads to the continuous evolution and expansion of cracks.
The fragments distribution of the nonaxisymmetric directional-focusing warhead
Authors: Li Xiang , Huang Guang-yan , Guo Zhi-wei , Feng Shun-shan
Published: June 2023

Charge structure, which can instantly release much energy, is a significant research point in explosive protection and warhead. A nonaxisymmetric directional-focusing warhead based on a quadrangular charge structure was designed, and the distribution of fragments from the warhead involved was studied. Numerical calculation research was carried out based on the ABAQUS finite element calculation software. The witness targets of fragments were obtained from an equal-scale explosion experiment, which provided experimental support for numerical simulation research. The results show that the nonaxisymmetric directional-focusing charge structure has a coupling effect on the directional and focusing of the fragments, and the fragments can form a concentrated damaging area. In this paper, the fragments distribution of the nonaxisymmetric directional-focusing warhead was obtained, and the damaging effect of the warhead involved was verified, which provides a foundation for the design and application of the nonaxisymmetric directional-focusing warhead.
An experimental and numerical study on the ballistic performance of a lightweight ceramic composite armor
Authors: Dong Gaoxiong , Li Xiangdong , Ji Yangziyi
Published: June 2023

In this paper, the ballistic limit velocity of 12.7mm armor-piercing incendiary projectile impacting a typical lightweight ceramic composite armor made of boron carbide ceramic and multi-layered composite materials (carbon fiber/aramid fiber/ultra-high molecular weight polyethylene fiber) was obtained experimentally. The process of impact was numerically simulated by the FEM-SPH method, and the results pointed out the characteristics of the penetration and the energy dissipation rule of each component of the ceramic composite armor. On this basis, the influence of thickness changing of the carbon fiber core layer on the ballistic performance of ceramic composite armor was studied with a typical “sandwich” structure, and the results showed that: when the thickness ratio of ceramic tile to the backing panel is about 1.5, the thickness changing of the carbon fiber core layer has the greatest effect on the ballistic performance. Under this thickness ratio, when the ratio of ceramic tile thickness to bullet diameter is greater than 1, the increase of carbon fiber core layer thickness will cause the ballistic performance index (BPI) of the target to decrease while the ratio is less than 1, the BPI increases or holds at first, and then decreases.
Penetration behavior of reactive projectiles impacting TC4 plates
Authors: Yuan Ying , Liu Aoxin , Xie Jianwen , Yu Qingbo
Published: June 2023

The reactive projectile presents a tremendous potential to induce the combined damage effect of kinetic energy and chemical energy to the plate. A series of ballistic impact experiments and numerical simulation studies were carried out to study the penetration behavior of reactive projectile against TC4 plate. The experimental results showed that with the impact velocity of the reactive projectile increasing from 537m/s to 682m/s, the damage mode of the plate gradually changes from bulge, cross crack to plug. According to the experimental results, the ballistic limit velocity of reactive projectile perpendicular penetrating 5mm TC4 is 648.33m/s. The numerical simulation results showed that the reactive projectile reaches GPa high pressure within a few microseconds when it impacted with the plate. During reactive projectile penetrating TC4 plate, the chemical energy release significantly improves the projectile penetrating ability, and the contribution of chemical energy to projectile penetrating can reach 55.07%.
Research on numerical simulation of submunition dispenser under different dispersion state
Authors: Shi Z , Wang S Y , Kang H B
Published: June 2023

In order to study the process of submunition airbag dispersal under different dispersion state, the p-t curve of gas generator combustion obtained by closed bomb test was transformed into the mass flow rate-time curve to simulate the process of airbag inflation. As the initial condition, it was input into the finite element model of submunition dispersal established by LS-DYNA software, and the results were compared with the literature data to verify the accuracy of the calculation method. Then, through the numerical simulation of airbag dispersion of submunition with different centroid positions and initial placement angles, the simulation results show that the dispersal velocity of the submunition decreases with the increase of the offset of the centroid in the x direction and the placement angle. The peak overload decreases with the increase of centroid offset and placement angle. The angular velocity of the submunition rotating around the y axis increases with the increase of the offset of the centroid in the x direction; the velocity of submunition rotating around x axis increases with the increase of the offset of centroid in y direction.
The penetration performance and matching design method of tandem warhead against ultra-high strength concrete
Authors: Si Xuena , Yu Rui , Wang Ping , Ji Long , Yu Wanqian , Li Rui , Liu Rongqiang
Published: June 2023

The penetration performance of the tandem warhead against ultra-high strength concrete and the matching relationship between the precursor shaped charge and the following kinetic energy warhead of the tandem warhead are researched to enhance the damage effect. For the precursor shaped charge, the formation and penetration properties of jet are studied in a combined experimental and numerical way. The value of kinetic energy/target borehole volume of C130 ultra-high strength concrete under the penetration of titanium alloy jet is obtained and the relationship of the depth and diameter of the precursory penetrating cavity is developed. For the following kinetic energy warhead, the numerical simulation of penetrating the pre-damage C130 ultra-high strength concrete is carried out and significant influence of the pre-damage crater’s depth and diameter on the relay penetration depth is observed. The matching method for the pre-damage crater resulting from the precursor shaped charge and the follow-through depth of the following kinetic energy warhead is set up on the basis of obtained penetration rules of two stages, which could provide helpful reference for the preliminary fast design of tandem warhead against ultra-high strength concrete.
Influence and its Mechanism of Non-reactive Fillers on the Dispersion Characteristics of the Fragments from Charge Structures
Authors: Liu Han , Zhao Yao , Guo Zhi-wei , Huang Guang-yan , Feng Shun-shan
Published: June 2023

With the diversified development of innovative warheads and the increasing threat of improvised explosive devices (IEDs), the charge structure filled with both explosives and non-reactive materials has attracted the attention of researchers, which is few studied. In order to obtain the fragmentation of the charge structure with part of the non-reactive filler, the X-ray radiography explosion experiment was carried out for an axisymmetric charge structure partially filled with nylon that serves as a typical non-reactive filler. The fragmentation and fragment dispersion characteristics of the charge structure were observed. Based on the results of X-ray experiments, the influence mechanism of shell breakage and fragment dispersion characteristics of the charge structure filled with non-reactive filler are analysed by using SPH numerical calculation method. The results show that the non-reactive filler will significantly affect the fragmentation of the shell and considerably reduce the fragment velocity of the fragments in the filling direction. However, the fragment dispersion direction of the charge structure is not affected by the non-reactive filler. The conclusions could be a foundation and reference for further research on new charge structures.
Improvement of high-power thyristor trigger circuit with switching-mode power supply for differential-mode noise reduction
Authors: Wei Jiufu
Published: June 2023

This paper focuses on the differential-mode (DM) noise of high-power thyristor (HPT) trigger circuit with switching-mode power supply (SMPS) in capacitive pulsed power supply (CPPS). Parasitic parameter models of components are discussed and analyzed. Based on the parasitic parameter models of components, a DM noise prediction model of HPT trigger circuit with SMPS is developed. The generation mechanism and propagation paths of the DM noise in HPT trigger circuit with SMPS are investigated. To reduce the DM noise, a capacitive SMPS technique is adopted in the HPT trigger circuit with SMPS. Simulation results validate the theoretical analysis.
Research on electromagnetic coupling characteristics of UAV circuits in the Complex electromagnetic environment
Authors: An Yashuai , Pan Xuchao , He Yong , Fang Zhong , Zheng Zhikai , Hao Yu , Du Wei , Zhou Yu , Chang Geng
Published: June 2023

The overall circuit model and Complex electromagnetic environment model of a typical UAV are built to explore the survivability of multirotor in the complex electromagnetic environment. The composite theoretical calculation model of the metal cavity aperture coupling and internal circuit coupling is constructed using the established UAV circuit model, which is based on the equivalent magnetic dipole algorithm and the FDTD algorithm. The terminal coupling voltage in the UAV circuit and the electromagnetic field distribution inside the metal cavity are estimated. CST software is used to simulate the response of UAV circuits in the same condition, and the correctness of the theoretical calculation model is confirmed. Then, the terminal coupling voltage of the PCB is used to create an electromagnetic coupling efficiency model. The findings reveal that the constructed composite theoretical model can accurately characterize the electromagnetic coupling characteristics of UAV circuits in the complex electromagnetic environment, with an error range of 1%~8%. When comparing the terminal coupling voltage of PCB in various complicated electromagnetic environments, the High-power microwave (HPM) has the maximum coupling efficiency. HPM initially causes the UAV circuits to attain the damage threshold under identical event conditions and target specifications. The findings could be used as a guide for multirotor circuit board protection in the complex electromagnetic environment, as well as for the development of high-power electromagnetic pulse weaponry.
Numerical Simulation of High Power Microwave Coupling to Typical Individual Inertial Device
Authors: Zheng Zhikai , Pan Xuchao , An Yashuai , Hao Yu , Du Wei , Zhou Yu , Chang Geng , Wang Siwei
Published: June 2023

HPM (high-power microwave) weapons become the major threat to individual equipment which is developing to be unmanned and intelligent. A typical inertial device of individual equipment is taken as the research object to find out its coupling paths based on the analysis of function and structural characteristics, and the effects of HPM coupling to the typical inertial device are simulated by the numerical simulation software CST. The results shows that power and signal cables of MEMS (Micro-Electro-Mechanical System) accelerometer are the main coupling paths of HPM; The power cable has size coupling effect which is strongest when the sum of the cable length and twice the distance to the “ground” is equal to odd times of quarter wavelength, and weakest when the cable length is equal to even times of quarter wavelength; The signal cable has wavelength coupling effect that is positively correlated with cable length which is less than wavelength, and not affected by cable length which is greater than wavelength; The screen in signal cable not only greatly reduces the peak value of coupling voltage, but also effectively reduces the influence of cable length on the coupling effect. The research results provide support for the protection of individual inertial devices, and also provide a reference for the design of HPM weapons.
Study of mechanical properties of cylinder under transient multi-physical field coupling conditions
Authors: Tian N , Liu J G , Gao Y , Wang K , Liu Z C
Published: June 2023

The use of lightweight metal cylinders is of great significance to artillery weapon systems in terms of significant mass reduction, service life extension, power consumption reduction and operational effectiveness. Based on the load conditions provided by the classical internal ballistic theory, a high precision finite element model is solved by the explicit integration algorithm with central difference. The results show that the maximum stress of the thin-walled cylinder increases linearly with the increase of the initial clearance, while the maximum extraction force increases first and then decreases, while the influence of temperature on the extraction force cannot be ignored. Therefore, the design of the initial gap between the thin-walled cylinder and the thick-walled cylinder should be designed to ensure that the maximum stress of the thin-walled cylinder does not exceed the maximum permissible stress and to meet the minimum extraction force, while choosing the correct extraction timing can effectively reduce the extraction force.
Research on testing method of attitude angle in projectile bore of small caliber electromagnetic weapon
Authors: Li Shili , Cao Zhiyuan , Lei Qiang , Qin Peiyu
Published: June 2023

Aiming at the influence of the attitude angle in the bore of a small calibre electromagnetic weapon on the stability of the projectile, a method for measuring the attitude angle of a projectile in the bore of a small caliber electromagnetic weapon is presented in this paper. According to the launching environment of the electromagnetic weapon and the structural characteristics of body tube, an integrated simulating missiles of anti-high overload is developed to convert the measurement of the attitude angle in the bore of the projectile into the measurement of laser spot displacement, the motion trajectory of the laser beam on the target plate in front of the muzzle is captured by a high-speed camera, and the displacement trajectory of the laser spot is measured by using adaptive spot displacement tracking technology based on centre of mass identification, and then the attitude angle of the projectile is obtained by trigonometric function calculation. Through laboratory verification and the theoretical analysis, the test error is ≤0.1′,it can realize high precision measurement of attitude angle in projectile bore. Finally, through the live firing test, the attitude angle of the projectile in the chamber of a certain electromagnetic weapon is obtained, and the effectiveness of the method is verified.
Performance Study of a Permanent-Magnet Eddy Current Damper for Guns Recoil Control
Authors: Liu Ning , Wang Nan-nan , Shen Yan-ping , Wang Biao-biao
Published: June 2023

Eddy current damper (ECD) is a promising device for dissipating kinetic energy in dynamic systems, this study is conducted to analyze the dynamic characterization and structural optimization of linear ECD under guns launch load. The recoil resistance of ECD under guns launch load is highly nonlinear at high recoil velocity, and the recoil resistance curve shows an increase-decrease-increasing shape like a “saddle”, which is not conducive to the stability of ECD during operation. The effects of several structural parameters on the dynamic characterization of ECD were studied in details. Results show that the air-gap size, the thickness of the magnetic conduction tube and conductive tube all have a notable influence on the recoil resistance curve of ECD. Moreover, BP neural network and genetic algorithm were used for structural optimization and the optimal value was verified by FEM. The optimization results indicate that the “saddle” shape of optimized recoil resistance curve is basically invisible. The fullness of the recoil resistance curve is significantly improved from 84.93% to 92.1%, which guaranteeing a smooth recoil movement. Finally, an impact loading test system for eddy current damper was built and the experimental results were basically consistent with the simulation results.
Research on Vibration Reduction design of Rifling Machining Tool for Gun barrel
Authors: Xu Xiangdong , Chen Guoguang , Guan Shixi , Zhang Bin , Li Shuai , Zhao Fuchun
Published: June 2023

The tool damping groove can effectively reduce the vibration amplitude, suppress vibration and avoid the occurrence of resonance. The output damping of the tool system is affected by the distribution of the damping groove on the outer surface. Therefore, four different distribution modes of vibration reduction grooves on the outer surface of the tool system were designed: pit distribution, vertical distribution, spiral distribution and horizontal distribution. Firstly, the Fluent software was used to simulate the damping flow field of the damping groove on the outer surface of the tool system under five different distribution modes including no damping groove, and it was found that the output damping effect of the damping channel with horizontal distribution of damping groove was better. Secondly, Simulink software is used to simulate its dynamic model, and it is intuitively shown that the flutter effect of the 3×4×4 horizontal distribution of the damping groove is better.
Superconductors in strong electric fields: Quantum Electrodynamics meets Superconductivity
Authors: Amoretti Andrea
Published: June 2023

A static electric field has always been thought to play little role in the physics of ideal conductors, since the screening effects of mobile carriers prevent it from penetrating deep into the bulk of a metal. Very recently however, experimental evidence has been obtained which indicates that static electric fields can be used to manipulate the superconductive properties of metallic BCS superconducting thin films, weakening the critical current. In this paper I will show how possible explanations to this striking effect can be found relying on the analogy between Superconductivity and Quantum Electrodynamics noticed by Nambu and Iona-Lasinio in the sixties. I will show that, following this parallelism, it is possible to predict a new phenomenon: the superconducting Schwinger effect. Secondly I will explain how this new microscopic effect can be connected to a modified Gizburg-Landau theory where additional couplings between electric field and the superconductive condensate are taken into account. Eventually I will connect these theoretical predictions to the experiments, proposing them as a possible explanation of the weakening of superconductivity due to an external electric field.
Quantum field corrections of the equation of state in cosmological space-time
Authors: Becattini F. , Roselli D.
Published: June 2023

A proper quantum statistical field theory framework for the decoupling of the cosmological plasma in curved space-time implies the appearance of corrections to the classical kinetic form of the stress-energy tensor of freely streaming particles. Such quantum corrections can become relevant even at long times after the decoupling and can significantly modify the relation between energy density and pressure, that is the equation of state.
A numerical solver for investigating the space charge effect on the
electric field in liquid argon time projection chambers
Authors: Tu Shuang Z. , Jiang Chao , Junk Thomas R. , Yang Tingjun
Published: June 2023

This paper reports the development of a numerical solver aimed to simulate the interaction
between the space charge (i.e. ions) distribution and the electric field in liquid argon time
projection chamber (LArTPC) detectors. The ion transport equation is solved by a time-accurate,
cell-centered finite volume method and the electric potential equation by a continuous finite
element method. The electric potential equation updates the electric field which provides the
drift velocity to the ion transport equation. The ion transport equation updates the space charge
density distribution which appears as the source term in the electric potential equation. The
interaction between the space charge distribution and the electric field is numerically simulated
within each physical time step. The convective velocity in the ion transport equation can include
the background flow velocity in addition to the electric drift velocity. The numerical solver has
been parallelized using the Message Passing Interface (MPI) library. Numerical tests show and
verify the capability and accuracy of the current numerical solver. It is planned that the
developed numerical solver, together with a Computational Fluid Dynamics (CFD) package which
provides the flow velocity field, can be used to investigate the space charge effect on the
electric field in large-scale particle detectors.
Laser calibration of the ATLAS Tile Calorimeter during LHC Run 2
Authors: Agaras M.N. , Ahmad A. , Blanco A. , Boumediene D. , Bonnefoy R. , Calvet D. , Calvetti M. , Chadelas R. , Conde Muino P. , Cortes Gonzalez A. , Crouau M. , Crozatier C. , Daudon F. , Davidek T. , Di Gregorio G. , Fiorini L. , Galhardo B. , Gris Ph. , Klimek P. , Lafarguette P. , Lambert D. , Leone S. , Maio A. , Marjanovic M. , Martins F. , Mlynarikova M. , Pereira B. , Pedro R. , Petukhova K. , Polacek S. , Rosten R. , Santoni C. , Scuri F. , Simon D. , Smirnov Y. , Solodkov A. , Solovyanov O. , Van Woerden M. , Veloso F. , Wilkens H.
Published: June 2023

This article reports the laser calibration of the hadronic
Tile Calorimeter of the ATLAS experiment in the LHC Run 2 data
campaign. The upgraded Laser II calibration system is described. The
system was commissioned during the first LHC Long Shutdown,
exhibiting a stability better than 0.8% for the laser light
monitoring. The methods employed to derive the detector calibration
factors with data from the laser calibration runs are also
detailed. These allowed to correct for the response fluctuations of
the 9852 photomultiplier tubes of the Tile Calorimeter with a total
uncertainty of 0.5% plus a luminosity-dependent sub-dominant
term. Finally, we report the regular monitoring and performance
studies using laser events in both standalone runs and during proton
collisions. These studies include channel timing and quality
inspection, and photomultiplier linearity and response dependence on
anode current.
A high-resolution real-time imaging system for observing the trajectories of neutron induced particles in a scintillator
Authors: Yamamoto Seiichi , Yoshino Masao , Nakanishi Kohei , Kamada Kei , Yoshikawa Akira , Kataoka Jun
Published: June 2023

High-resolution imaging of neutron induced particles is required in such methods as neutron radiography. However, the scintillation spots in a neutron-sensitive scintillator have not yet been imaged nor measured for size. We developed a high-resolution, real-time neutron induced particle imaging system for observing these particles' trajectories in a scintillator. The developed system is based on a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera combined with a lithium-containing silver-doped zinc sulfide (Li-ZnS(Ag)) scintillator plate. Neutrons from a californium-252 (252Cf) source were irradiated to the Li-ZnS(Ag) scintillator and imaged with the system. Using our system, we measured the scintillation spots of the neutron induced particles having different shapes in real time. In some of these measured scintillation spots, those with elliptical shapes were observed due to the trajectories of the particles in the scintillator. The spatial resolution calculated from the widths of the scintillation spots was ∼56 μm. Consequently, the developed imaging system is promising for research on neutron imaging that requires high spatial resolution.
Differentiation of greenhouse gases in corporate science-based targets improves alignment with Paris temperature goal
Authors: Bjørn Anders , Lloyd Shannon , Schenker Urs , Margni Manuele , Levasseur Annie , Agez Maxime , Matthews H Damon
Published: June 2023

Companies are increasingly setting greenhouse gas (GHG) emission reduction targets to align with the 1.5 °C goal of the Paris Agreement. Currently, companies set these science-based targets (SBTs) for aggregate GHGs expressed in CO2-equivalent emissions. This approach does not specify which gases will be reduced and risk misalignment with ambitious mitigation scenarios in which individual gas emissions are mitigated at different rates. We propose that companies instead set reduction targets for separate baskets of GHGs, defined according to the atmospheric lifetimes and global mitigation potentials of GHGs. We use a sector-level analysis to approximate the average impact of this proposal on company SBTs. We apply a multiregional environmentally extended input output model and a range of 1.5 °C emissions scenarios to compare 1-, 2- and 3-basket approaches for calculating sector-level SBTs for direct (scope 1) and indirect (scope 2 and upstream scope 3) emissions for all major global sectors. The multi-basket approaches lead to higher reduction requirements for scope 1 and 2 emissions than the current single-basket approach for most sectors, because these emission sources are usually dominated by CO2, which is typically mitigated faster than other gases in 1.5 °C scenarios. Exceptions are scope 1 emissions for fossil and biological raw material production and waste management, which are dominated by other GHGs (mainly CH4and N2O). On the other hand, upstream scope 3 reduction targets at the sector level often become less ambitious with a multi-basket approach, owing mainly to substantial shares of CH4and, in some cases, non-CO2long-lived emissions. Our results indicate that a shift to a multi-basket approach would improve the alignment of SBTs with the Paris temperature goal and would require most of the current set of companies with approved SBTs to increase the ambition of their scope 1 and scope 2 targets. More research on the implications of a multi-basket approach on company-level SBTs for all scope 3 activities (downstream, as well as upstream) is needed.
Elevation dependency of future degradation of permafrost over the Qinghai-Tibet Plateau
Authors: Zhang Guofei , Mu Cuicui , Nan Zhuotong , Wu Xiaodong , Cheng Guodong
Published: June 2023

Global warming has caused widespread permafrost degradation, but the geographic regularity of permafrost degradation is unknown. Here, we investigated the three-dimensional features of future permafrost degradation on the Qinghai-Tibetan Plateau. Our findings show that permafrost degradation under shared socioeconomic pathways (SSPs) has obvious three-dimensional characteristics. In comparison to latitude and aridity, permafrost degradation is closely related to elevation, i.e. it slows with elevation, a phenomenon known as elevation-dependent degradation. The pattern of elevation-dependent degradation is consistent across four subzones and is strongly linked to thermal conditions that vary with elevation. Under SSP2-4.5, SSP3-7.0, and SSP5-8.5 scenarios, remarkable elevation-dependent warming (EDW) is observed at 3600–4900 m, but changes in mean annual ground temperature of permafrost and EDW as altitude rises are anti-phase. Under any SSP, the magnitude of mean annual air temperature along altitude belts determines the degree of permafrost degradation (R
2 > 0.90). This research provides new insight on the evolution of permafrost.
Yours, mine, and ours: gender, intra-household dynamics, and financing solar home systems in Tanzania
Authors: Gill-Wiehl Annelise , Ojong Nathanael
Published: June 2023

The financing of off-grid solar is a crucial component for the expansion of electricity access, particularly across sub-Saharan Africa. Emerging literature in energy access research analyzes the role of gender and inequalities in access and subsequent outcomes; however, beyond gendered outcomes, the field has yet to interrogate the intra-household dynamics of obtaining access. The literatures of the intra-household dynamics of budgeting and energy access have remained distinct. Bridging these literatures, we present the first analysis of if and how intra-household dynamics relate to how individuals obtain energy access through our specific case of financing solar home systems (SHSs). Drawing on 113 interviews across four districts in Tanzania, we employ qualitative thematic analysis and quantitative generalized linear model-based prevalence ratio estimates. We find five categories of how SHS adopters describe gender and intra-household dynamics relating to the financing of their SHS. We find it inappropriate to treat the household as a single entity as in half our sample, women are either solely or jointly responsible for financing the SHS. Female headed households have a higher prevalence of relying on debt to finance their SHS, while households with female financial decision-making power have a higher prevalence of relying on savings. The unitary model of a household limits the sector’s ability to efficiently support multi-adult households as they navigate individual needs and preferences in the financing and ultimate acquisition of the SHS. Researchers, policy makers, and the private sector could further acknowledge and explore intra-household dynamics and consider shifting the focus away from debt-based financing towards energy-dedicated savings accounts for female customers and improving borrowing conditions for female headed households.
Schrödinger equation driven by the square of a Gaussian field: instanton analysis in the large amplification limit
Authors: Mounaix Philippe
Published: June 2023

We study the tail of p(U), the probability distribution of

U
=
|
ψ
(
0
,
L
)

|
2

, for

ln
U
≫
1

,

ψ
(
x
,
z
)

being the solution to

∂
z

ψ
−

i

2
m

∇

⊥

2

ψ
=
g
|
S

|
2

ψ

, where

S
(
x
,
z
)

is a complex Gaussian random field, z and x respectively are the axial and transverse coordinates, with

0
⩽
z
⩽
L

, and both

m
≠
0

and g > 0 are real parameters. We perform the first instanton analysis of the corresponding Martin-Siggia-Rose action, from which it is found that the realizations of S concentrate onto long filamentary instantons, as

ln
U
→
+
∞

. The tail of p(U) is deduced from the statistics of the instantons. The value of g above which

⟨
U
⟩

diverges coincides with the one obtained by the completely different approach developed in Mounaix et al (2006 Commun. Math. Phys.
264 741). Numerical simulations clearly show a statistical bias of S towards the instanton for the largest sampled values of

ln
U

. The high maxima—or ‘hot spots’—of

|
S
(
x
,
z
)

|
2

for the biased realizations of S tend to cluster in the instanton region.
Can weight hysteresis in a neural network judge the continuity/discontinuity of a phase transition?
Authors: Nakamura Katsumi , Fuchizaki Kazuhiro
Published: June 2023

We often encounter hysteresis associated with short-term memory stored in our brain when we see continuously varying pictures in back-and-forth directions. We expect a neural network (NN) to also experience hysteresis in recognizing information back and forth depending on its continuity. This study shows that using equilibrium configurations obtained from the well-defined models undergoing the phase transitions as learning data, the weights of an NN can exhibit hysteresis behaviors against sequential learning, increasing (or decreasing) an external field or temperature. Indeed, the weights’ hysteresis clearly shows up when an NN learns back and forth a series of configurations passing through a continuous transition or a crossover, whereas no hysteresis arises for discontinuous transitions. This fascinating finding opens up a new application of machine learning to judge the order of a phase transition from the suitably visualized changes in microscopic configurations without setting a specific model.
Quality of mangosteen on registered and non-registered farmers in Payakumbuh West Sumatra to supporting exports
Authors: Sulistyaningrum A. , Qomariah Hayati N. , Mulyono D. , Prabawati S. , Laila Sayekti A. , Marlina L. , Jawal Anwarudin Syah M. , Sjafrina N. , Noviarli  , Alfia Anugrah Cahyati R.
Published: June 2023

The demand for mangosteen exports is wide open, but the ability to meet the quota is still low. In this regulation, the Packing House Operation (PHO) requires that the mangosteen for export must come from registered farmers. But in reality only rely on registered farmers cannot meet the quota. The purpose of this study was to analyze the quality of mangosteen from registered and non-registered farmers. This research was conducted by using the T-test by comparing the quality of the mangosteen on registered and non-registered farmers. The results showed that the registered and non-register mangosteen originating from Payakumbuh showed no significant differences in the seven parameters, namely peel color, yellow latex in the peel, yellow latex in the flesh, scars on the peel, fruit weight, total soluble solids, and acid content. Meanwhile, the parameter of vitamin C content was significantly different with a significance value of 0.045. So that the export policies of registered and non-registered farmers need to be reviewed, because it is less effective and efficient. Because of the findings in the field, mangosteen from registered and non-registered farmers entered the PHO.
Characteristics of gluten-free cookies from konjac, jack beans and dragon fruit (Hylocereus undatus)
Authors: Nurfirdausi A , Aini N , Dwiyanti H
Published: June 2023

The development of gluten-free cookies can be done using fiber-rich konjac flour. The addition of protein sources will reduce the GI of the ingredients so that the addition jack bean flour which is a local food is expected to increase its functional properties. To improve its appearance and functional properties, dragon fruit which is rich in anthocyanins is added as a functional component. The aim of the study was to determine the right formulation to produce gluten-free food from konjac tubers, jack bean and dragon fruit with good nutritional and sensory values and favored by panelists. The study used a factorial Completely Randomized Design with 2 factors. The first factor is the proportion of konjac flour: jack bean flour consists of 3 levels, namely 80:20, 70:30 and 60:40. The second factor was the proportion of dragon fruit consisting of 3 levels, namely 10, 20 and 30%. The variables studied at this stage are nutritional values including levels of total protein, fat, minerals, water, ash, yield, and carbohydrates as well as sensory properties including aroma, texture, taste, colour, aftertaste, flavour, and overall acceptability. The conclusion from this study is that the ratio of the use of konjac tuber flour and jack bean flour, as well as the proportion factor of the use of dragon fruit concentrate have an effect on moisture content, ash content, fat content, total protein content, carbohydrate content, and yield of the resulting cookies. In addition to the results of sensory analysis, the results showed a significant effect of the use of the ratio of flour and dragon fruit concentrate, on the attributes of color, aroma, taste, texture, flavour, aftertaste, and overall acceptance of cookies.
Agronomic performance and correlation of growth components, yield components and production on 30 F3 lines of new plant type of black rice specific to highland ecosystems
Authors: Limbongan Yusuf L , Parari Trisday Y , Limbongan Amelia A , Palese Menatopan M
Published: June 2023

Many high-yielding varieties of rice have been released, but generally lack good quality. This study aimed to examine the agronomic performance of several new plant types of black F3 rice lines at two medium altitude. The research was carried out on rice fields in Tallunglipu District, North Toraja Regency with an altitude of 850 m above sea level. This research took place from May 2020 to November 2022. This study used the Single Seed Descend selection method which was arranged in randomized block design pattern at each location. The genetic material tested consisted of 30 F3 lines resulting from two combinations of crosses between Toraja local black rice, each of which was crossed with a national superior variety and 3 comparison varieties, namely Pare Ambo, Pare Lallodo and Inpari 4 which were repeated 3 times. The observational data were analyzed for variance and if there was a significant effect, then the Honestly Significant Difference was 5% and the value of closeness between characters was tested for correlation and weighted analysis (WINDEX) was performed to select the strains. The results showed that the character had a close correlation with productivity, namely the character of the weight of pithy grain per clump, the maximum number of tillers and the number of pithy grain per panicle. The lines with the best productivity were F3UKIT104-2-194 (5.7 tons/ha) and F3UKIT104-2-197 (5.4 tons/ha). The selected strains based on Windex selection are UKIT104-2-197, UKIT 104-2-194, UKIT 104-2-298, UKIT 104-2-089, UKIT 104-2-127, UKIT-101-2-131, UKIT-101-2-218, UKIT 104-2-003, UKIT 104-2-148, UKIT-101-2-002, UKIT-101-2-003, UKIT-104-2-046, UKIT 104-2-064, and UKIT 104-2-001.
Modeling green roofs in tropical housing to support micro-scale food security
Authors: Yuliani Sri , Triratma Bambang
Published: June 2023

Research on green roofs in tropical residential buildings has the opportunity to be a substitute for productive green spaces. This research implements several vegetable plants as building roof covering elements, i.e., peanut, eggplant, chili, and tomato. Experimental research was applied jointly for six months on four types of vegetables on a green roof covering an area of sixteen square meters. The green roof model consists of a green roof model on concrete and corrugated zinc through a floating technique as a roof model engineering. The aim of this research is to examine the roof as a substitute for green space in buildings. The results showed that the four types of vegetables could grow well on both roof models, both types of green roof have the opportunity to be implemented in residential areas, resulting in fruit that could be consumed on a household micro scale.
Application method of check all that apply on sensory evaluation of black garlic supplemented yogurt
Authors: Priadi G , Setiyoningrum F , Afiati F , Millatina N R N
Published: June 2023

The sensory analysis can assess and describe the sensory attributes of food products. The aim of this study was to describe all the sensory attributes present in black garlic incubation 21 days at humidity 70-90 and temperature 70°C supplemented yogurt using the Check All That Apply (CATA) method, one of the methods that are simple and rapid. The test used 75 selected panellists with the criteria of liking yogurt and frequently consuming yogurt. Black garlic supplementation on yogurt causes attributes of granular mouthfeel, granular texture, garlic flavor, pungency, licorice aftertaste, and salty on yogurt. The attributes are different from standard yogurt according to the selected panellist’s perceptions. Plain flavor, milk flavor, and milk aroma are the high liking attributes of the product.