bluuebunny/crossref_metadata_2025 huggingface dataset:
The reduction of Netspeak in Mandarin computer-mediated communication: a least effort motivation at the utterance level
Authors: Zhou Yong , Wu Yicheng
Published: June 2024

This article addresses the phenomenon of Netspeak reductions with special reference to Mandarin computer-mediated communication. A tentative classification of Chinese Netspeak reductions is first provided, namely, two-, three-, or four-character reductions occurring at both the lexical and the syntactic levels and other atypical reductions. It is then proposed that Zipf’s Principle of Least Effort, which usually works at the lexical level, can work as well at the utterance level and can account for the increasing number of Netspeak reductions in daily communication, that is, the frequency of using Netspeak reduction determines its vitality and distribution.
Navigating the uncertainty: the impact of a student-centered final year project allocation mechanism on student performance
Authors: Yuan Hang , Yuan Wenwen , Duan Sixuan , Yong Ruiqi , Jiao Keran , Wei Yan , Leach Mark , Li Na , Zhang Xiaojun , Lim Eng Gee , Song Pengfei
Published: June 2024

The Final Year Project (FYP) is one of the most important courses for every undergraduate student, and the effective operation of the FYPs in higher education still faces challenges, such as uneven resource distribution and limited efficiency. This study reports a mixed-methods approach to study the impact of a student-centered FYP allocation mechanism on student performance. This research aims to investigate how aligning students’ FYP choices with their interests can inspire motivation and enhance academic performance. More importantly, this mechanism improves students’ academic resilience, enabling them to navigate unexpected contextual factors. The study’s findings take into account various aspects, including student satisfaction with the allocation process, future improvement methods, and the relationship between interest and context. The outcomes observed in this study support our hypotheses, indicating the improvements in students’ academic performance as well as the pass and completion rates. Moreover, this research contributes to ‘resilience theory’ by exploring students’ adaptability to contextual changes and their enhancement of academic resilience. This study proposes recommendations for cultivating a dynamic student-centered classroom environment. Future work could pay attention to addressing the limitations of this study, exploring other factors influencing FYP allocation, and integrating more quantitative measures for a comprehensive assessment of its impact.
Violent conflict and multinational enterprises: identifying key frontiers in international business policy research
Authors: Liu Chang , Eden Lorraine , Li Dan
Published: June 2024

Violent conflicts are events that involve the purposeful use of violence by state and/or non-state actor(s) to achieve political objectives, which result in disruptions to the institutional environment where actors such as civil society and multinational enterprises (MNEs) are situated. Examples of violent conflicts include civil and interstate wars and terrorist attacks. Violent conflicts typically have multiple, often devastating consequences that pose difficult policy challenges for governments and MNEs. This perspective offers an international business (IB) research and policy agenda to advance our understanding of the linkages between violent conflict and MNEs, focusing on three IB research and policy frontiers: the mechanisms through which MNEs are exposed to violent conflicts globally, MNE strategies and violent conflicts, and the interplay between MNEs and violent conflict environments. We also discuss appropriate datasets and research methods for studying MNEs and violent conflict.
Band structure transformation of the avoided crossing type in impure graphene
Authors: Skrypnyk Yuriy V. , Loktev Vadim M.
Published: June 2024

We show that the electronic spectrum in graphene, not unlike in other low-dimensional systems, can manifest a sharp impurity resonance near the Dirac point due to the presence of a single weakly coupled impurity described by the Fano model. It is demonstrated that, according to the established scenario, the electronic band structure of graphene undergoes a kind of transformation, specifically of the avoided crossing type, when the concentration of such short-range impurities increases. In this transformation process, main events unfold close to the impurity resonance energy, and, therefore, they relate to the most intriguing domain of the energy spectrum of graphene. The avoided crossing transformation develops in a threshold manner. Namely, it starts when the impurity concentration exceeds a critical value determined by the considerable spatial overlap of individual impurity states. Unlike former cases of such band structure transformations in low-dimensional systems, our findings unveil the formation of a new—impurity—Dirac point in the spectrum alongside the original shifted one, which doubles their number in the disordered system. The resulting electronic spectrum also features a single worthy of attention concentration broadening area or mobility gap of a substantially reduced width around the impurity resonance energy. Band edge smearing areas at old and newly formed Dirac points, where electronic states are also localized, are found to be negligibly narrow. Our analysis suggests that controlling the position of the Fermi level in the disordered system under study may allow observation of the re-entrant metal–insulator transition. The Fermi level entering and exiting the mobility gap causes the metal–insulator and insulator–metal transitions.
Studying mechanism of anisotropic crack generation on C-, R-, A-, and M-planes of sapphire during ultra-precision orthogonal cutting using a visualized slip/fracture activation model
Authors: Kwon Suk Bum , Min Sangkee
Published: June 2024

With the growing demand for the fabrication of microminiaturized components, a comprehensive understanding of material removal behavior during ultra-precision cutting has become increasingly significant. Single-crystal sapphire stands out as a promising material for microelectronic components, ultra-precision lenses, and semiconductor structures owing to its exceptional characteristics, such as high hardness, chemical stability, and optical properties. This paper focuses on understanding the mechanism responsible for generating anisotropic crack morphologies along various cutting orientations on four crystal planes (C-, R-, A-, and M-planes) of sapphire during ultra-precision orthogonal cutting. By employing a scanning electric microscope to examine the machined surfaces, the crack morphologies can be categorized into three distinct types on the basis of their distinctive features: layered, sculptured, and lateral. To understand the mechanism determining crack morphology, visualized parameters related to the plastic deformation and cleavage fracture parameters are utilized. These parameters provide insight into both the likelihood and direction of plastic deformation and fracture system activations. Analysis of the results shows that the formation of crack morphology is predominantly influenced by the directionality of crystallographic fracture system activation and by the interplay between fracture and plastic deformation system activations.
RBF neural network dynamic sliding mode control based on lambert W function for piezoelectric stick–slip actuator
Authors: Li Yan , Fan Piao , Zhang Zhenguo , Li Yuelong , Yang Shitong , Lu Xiaohui
Published: June 2024

This paper presents a novel approach for increasing the precision of high-precision positioning control experiments for a piezoelectric stick–slip actuator system. This is achieved through dynamic sliding mode control with a radial basis function neural network (RBFNN) based on the Lambert W function. The proposed control strategy is divided into two parts: scanning mode control and stepping mode control. For scanning control, a dynamic sliding mode controller was designed to solve the jitter problem in traditional sliding mode control. The introduction of the RBFNN avoids the effects of uncertainty terms and unknown disturbances in the model; reduces the controller gain, which must be adjusted; and improves the robustness of the system to disturbances. The stability of the dynamic sliding mode controller based on the RBFNN was verified through a Lyapunov analysis, and the Lambert W function was introduced to optimize the controller parameters responsible for the time lag in the closed-loop control system. This optimization improved the system’s robustness against time delays, which can adversely affect its performance. Simulation and experimental results indicated that the proposed control strategy achieved a positioning control accuracy of <40 nm during the scanning phase and was robust in the presence of a load. In long-distance positioning control experiments, the control strategy achieved a control target of 40 μm while maintaining the positioning control accuracy and reducing the impact of time lag on the system.
Electron beam profile measurement using enhanced dual-techniques in high heat flux test facility at Institute for Plasma Research
Authors: Belsare Sunil , Bhope Kedar , Mehta Mayur , Khirwadkar Samir , Patel Tushar , Swamy Rajamannar , Sahu Srikanta , Mokariya Prakash , Patel Nikunj
Published: June 2024

During operation of an ITER-like plasma fusion device, Plasma Facing Components (PFCs) of a divertor are subjected to steady-state and transient heat loads of up to 20 MW/m2. At High Heat Flux Test Facility (HHFTF) at Institute for Plasma Research, PFCs are subjected to such heat flux scenarios using 200 kW electron beam (EB). A heat flux distribution on PFCs is significantly influenced by the EB profile and scanning technique. A novel dual-technique approach is used to measure EB cross-sectional profiles in HHFTF. A single setup is designed, fabricated, and installed in HHFTF consisting of (1) the knife-edge technique involving graphite and tungsten rectangular tiles bonded on a copper block adjacent to each other to form a sharp edge and (2) the wire scanner technique wherein tungsten wires are placed at equal distances. Current collected by the setup is measured as EB is rastered across the wire and tile boundaries. Current measured as a function of EB position is used to calculate the EB profile using a customized LabVIEW software application. Experiments are conducted by varying EB power from 28 to 200 kW and correspondingly the full width at half maximum of the EB profile grows from 5.30 to 16.04 mm, as observed by both these techniques. The COMSOL Multiphysics simulation of the wire scanner technique is performed to verify the experimental results. X-ray and infra-red imaging diagnostics of HHFTF are also used to measure the EB profile in a unique and first-of-its-kind way, and they are found to agree well with the dual-technique measurements.
A novel coupled hydrothermal–mechanical model and numerical analysis of unsaturated bentonite considering the influence of salt ions
Authors: Chen Peipei , Jin Ming , Wang Yueqian , Yin Fengling , Xu Tao , Zhu Ruisong
Published: June 2024

The quantitative research on swelling properties of bentonite considering the influence of salt ions under the effect of hydrothermo-mechanical coupling is relatively weak. Based on a calculation model for the swelling characteristics of bentonite from a fractal perspective, this work proposes a novel coupled multifield control equation for unsaturated bentonite considering the influence of salt ions. The numericalization of the coupling control equation was completed by secondary development of a numerical analysis platform. The new theoretical model’s dependability and validity were validated by comparing it to experimental data. The evolution of the related-field quantities under the multifield coupled effect in salt-bearing environments was obtained, and the effect of salt ion concentration was analyzed. The calculation showed that the temperature of bentonite changed periodically with changing ambient temperature. Temperature gradient induces migratory movement of water from high to low temperature regions. The hollow axisymmetric soil sample gradually saturated from outside to inside with increasing water injection rate at the outer cylindrical surface. The swelling pressure of bentonite will increase with an increase in water content, whereas the presence of salt ions weakened the swelling behavior. Temperature and relative humidity were less affected by salt ion concentration.
Selective area grown photonic integrated chips for completely suppressing the Stokes shift
Authors: He Rui , Wang Yongxiang , Song Yijian , Ran Junxue , Yang Jiankun , Wu Jin , Hu Qiang , Wei Xuecheng , Wang Junxi , Wei Tongbo
Published: June 2024

In this work, we report on the selective area growth (SAG) of InGaN multiple quantum well (MQW) structures to completely suppress the phenomenon of the Stokes shift in monolithically integrated photonic chips. The original green MQW region is designed as the integrated photodetector (PD), while the SAG blue MQW region acts as the integrated light-emitting diode (LED). The detection spectra of the PD can completely cover the emission spectra of the LED, greatly improving the on-chip optical connection by the complete suppression of the Stokes shift. Thus, the bottleneck of on-chip optical connection based on spectra-tail overlap in integrated photonic chips has been broken. Under the same operating current, the photocurrent of the SAG integrated PD reaches 11.8 μA, while the conventional chip achieves only 0.6 μA. By SAG method, the photo-to-dark current ratio of integrated PD exhibits about two orders of magnitude increase under 0 V bias. Undoubtedly, the SAG technology provides a strategy to further improve the on-chip optical signal transmission efficiency of the MQW structure integrated photonic chips.
Orthogonal experimental study of ultrasound-assisted fused deposition molding
Authors: Wang Haixiong , Liu Shuhao , Ying Jun
Published: June 2024

To improve the quality of fused deposition molding (FDM), we introduced ultrasonic vibration into the molding process to enhance the strength of the tensile samples. We used the response surface method to optimize the FDM molding process. We carried out orthogonal experiments to investigate the effects of ultrasonic power and process parameters (extrusion temperature, hotbed temperature, and delamination thickness) on the mechanical properties of fused deposition acrylonitrile butadiene styrene products. We obtained the quadratic regression equations and response surfaces of the data through analysis of variance and significance analysis by software. Last, we received the optimum combination of process parameters for tensile strength as extrusion temperature 233.85 °C, hotbed temperature 93.38 °C, delamination thickness 0.1 mm, and ultrasonic power 43.09 W.
Unveiling hemodynamic pulsatile flow dynamics in carotid artery stenosis: Insights from computational fluid dynamics
Authors: Kaid Noureddine , Benyamina Leila , Menni Younes , Alkhafaji Mohammed Ayad , Bayram Mustafa , Alshammari Badr M. , Kolsi Lioua
Published: June 2024

This paper presents a comprehensive model of hemodynamic pulsatile flow within the carotid artery, examining both normal conditions and those affected by stenosis. The primary focus lies in visualizing shear stress along the inner walls, aiming to elucidate how stenosis alters blood flow characteristics and subsequently impacts plaque deposition. Utilizing advanced computational fluid dynamics simulations, temporal variations in flow patterns, velocity profiles, and pressure gradients resulting from stenosis are captured, thereby elucidating the mechanical forces exerted on arterial walls. Moreover, this study analyzes the influence of hemodynamic parameters, such as Reynolds number, Womersley number, and arterial geometry, on flow disruption and stagnation points. Such insights are critical in understanding the mechanisms underlying plaque formation and progression. Critical thresholds of shear stress and flow patterns contributing to endothelial dysfunction and atherosclerotic lesion initiation are identified by comparing hemodynamic environments in healthy vs stenotic arteries. The results demonstrate significant differences in hemodynamic characteristics between stenosed and normal arteries, particularly near systolic peaks. Stenosed arteries exhibit notably higher velocities at arterial bifurcations during systole than normal arteries, indicative of altered flow dynamics. In addition, stenosis disrupts flow patterns, leading to vortex formation at locations beyond systolic peaks. Overall, findings from this research advance our understanding of cardiovascular disease pathogenesis and provide valuable insights into the hemodynamic effects of arterial stenosis.
Calorie restriction and calorie-restriction mimetics activate chaperone-mediated autophagy
Authors: Jafari Maryam , Macho-González Adrián , Diaz Antonio , Lindenau Kristen , Santiago-Fernández Olaya , Zeng Mei , Massey Ashish C. , de Cabo Rafael , Kaushik Susmita , Cuervo Ana Maria
Published: June 2024

Chaperone-mediated autophagy (CMA) is part of the mammalian cellular proteostasis network that ensures protein quality control, maintenance of proteome homeostasis, and proteome changes required for the adaptation to stress. Loss of proteostasis is one of the hallmarks of aging. CMA decreases with age in multiple rodent tissues and human cell types. A decrease in lysosomal levels of the lysosome-associated membrane protein type 2A (LAMP2A), the CMA receptor, has been identified as a main reason for declined CMA in aging. Here, we report constitutive activation of CMA with calorie restriction (CR), an intervention that extends healthspan, in old rodent livers and in an in vitro model of CR with cultured fibroblasts. We found that CR-mediated upregulation of CMA is due to improved stability of LAMP2A at the lysosome membrane. We also explore the translational value of our observations using calorie-restriction mimetics (CRMs), pharmacologically active substances that reproduce the biochemical and functional effects of CR. We show that acute treatment of old mice with CRMs also robustly activates CMA in several tissues and that this activation is required for the higher resistance to lipid dietary challenges conferred by treatment with CRMs. We conclude that part of the beneficial effects associated with CR/CRMs could be a consequence of the constitutive activation of CMA mediated by these interventions.
The dissociation of H2O on the γ-U (110) and (100) surfaces: an ab initio study
Authors: Yang Yue , Zhu Songlin , Xie Minghong , Tian Xiaofeng
Published: June 2024

The dissociation of H2O on γ-U (110) and γ-U (100) surfaces has been studied by using ab initio molecular dynamics simulations at an elevated temperature of 800 K. The simulation results show the dissociation of H2O into the OH group and H atom, which are finally adsorbed on the uranium surface. The dissociation results from electronic interactions between surface uranium 6d/5 f states and the s orbitals of H and the 2p orbitals of O. Additionally, the hybridization between the 6d orbital of surface uranium and the 2p orbital of oxygen plays a dominant role in dissociative adsorption. A significant charge transfer from the uranium surface to the O and H atoms is observed, indicating the formation of U–O and U–H chemical bonds. Specifically, for γ-U (110) surface, the most preferred site for OH is the 3-fold hollow site and H occupies the bridge site or the 3-fold hollow site. On the other hand, for γ-U (100) surface, OH prefers to adsorb on the bridge site and H occupies the 3-fold hollow site or the bridge site. Furthermore, when H2O is placed on the TOP site, its initial dissociation on the γ-U (110) surface is easier compared to the γ-U (100) surface.
The surface chemistry of the atomic layer deposition of metal thin films
Authors: Zaera Francisco
Published: June 2024

In this perspective we discuss the progress made in the mechanistic studies of the surface chemistry associated with the atomic layer deposition (ALD) of metal films and the usefulness of that knowledge for the optimization of existing film growth processes and for the design of new ones. Our focus is on the deposition of late transition metals. We start by introducing some of the main surface-sensitive techniques and approaches used in this research. We comment on the general nature of the metallorganic complexes used as precursors for these depositions, and the uniqueness that solid surfaces and the absence of liquid solvents bring to the ALD chemistry and differentiate it from what is known from metalorganic chemistry in solution. We then delve into the adsorption and thermal chemistry of those precursors, highlighting the complex and stepwise nature of the decomposition of the organic ligands that usually ensued upon their thermal activation. We discuss the criteria relevant for the selection of co-reactants to be used on the second half of the ALD cycle, with emphasis on the redox chemistry often associated with the growth of metallic films starting from complexes with metal cations. Additional considerations include the nature of the substrate and the final structural and chemical properties of the growing films, which we indicate rarely retain the homogeneous 2D structure often aimed for. We end with some general conclusions and personal thoughts about the future of this field.
Geothermal Exploration in Hululais Geothermal Field, Lebong Regency, using a 1D Magnetotelluric Approach to Estimate The Depth of Reservoir Rocks
Authors: Suhendra  , Johan Henny , Refrizon  , Ikhlas Fadli Darmawan , Halauddin  , Mandela Afrizen , Syakban Idris Beni , Lidiawati Liza , Purqan Aulia
Published: June 2024

Indonesia continues to rely heavily on hydrocarbon energy sources. However, in order to ensure the country’s long-term economic growth, it must diversify its energy investments and use renewable energy sources. Through tapping into the country’s vast untapped geothermal resources, the country can meet its rising energy needs in a sustainable and effective manner, all while contributing to mitigating climate change’s worst effects. Lebong Regency, Bengkulu, Indonesia, is the site of the Hululais Geothermal Field. Geothermal energy could be extracted from the area’s hydrothermal systems, as evidenced by the existence of surface hot springs and sulfur craters. In order to determine how deep the geothermal reservoir rocks at Hululais go, a thorough investigation of the area has been carried out using the magnetotelluric (MT) technique to probe the underlying lithological conditions. More than 10 kilometers of MT data were collected across 4 different survey stations for this study’s 1D inversion. The information was gathered with the help of a Metronix ADU-07e MT instrument. The 1D occam inversion results explain the resistive zone connected to the flow of thermal fluid. Hot springs and sulfur craters can be seen on Hululais’s surface, indicating the fluid flows beneath the island’s crust. 1D Occam inversion of MT data measured in the Lebong District can identify geothermal reservoir, where the depth of the geothermal reservoir is 400 meters in subsurface, which is indicated by a high resistivity value (> 500 Ω.m).
Preliminary Study on Structure of Carbon Derived from Palm Oil Shell
Authors: Wardhani Mas’udah Kusuma , Tiara Permatasari Gabriella , Astuti Fahmi , Asih Retno , Darminto Darminto
Published: June 2024

Palm shells are waste that is produced every year due to the large demand for palm oil. The potential for carbon derivatives in palm shell charcoal waste that can be extracted is more like activated carbon. Therefore, this research aims to provide an explanation of the ability of palm shell charcoal carbon as a residual component of palm oil processing that is affordable and abundantly available, which if maximized properly will be the forerunner to the development of technology that has added value. The capabilities of Palm Shell Charcoal can be applied for technical applications with further development. It is hoped that this study will provide initial information for scientists and policy makers in the fields of environmental conservation and technology. Palm shell charcoal (ACKS) that has been washed, dried and made into powder is subjected to DSC-TGA, FTIR, XRD, SEM-EDX testing. The XRD results show that there is a main broad peak that appears around the 2θ ∼23° angle which corresponds to the (002) plane and also a narrow peak appears at the 26° angle which indicates graphite growth. Meanwhile, the FTIR results show that many of the bonds formed are C=O, C-O, C=C and O-H bonds which indicate the presence of hard carbon.
In-situ Synchrotron Radiation XRD Crystal Structure and Microstructure Analysis of CaO-ZrO2 solid-solution at 1100°C with Prolonged Heating
Authors: Hariyanto Budi , Eka Wahyuni Afra , Ely Sufilman , Wannapaiboon Suttipong , Saiyasombat Chatree , Yani Purwaningsih Sri , Pratapa Suminar
Published: June 2024

The structural analysis of the CaO-ZrO2 solid-solutions was carried out using in-situ synchrotron radiation X-ray diffraction (SR-XRD). CaO-ZrO2 solid-solutions with 0, 2.5, and 5 at.% CaO contents were synthesized via a solid-solid ball milling technique. The amorphous ZrO2 powder was synthesized via co-precipitation using ZrCl4 and NH4OH as precursors, while the CaO powder was purified from a local limestone. In-situ SR-XRD measurements were conducted on the CaO-ZrO2 mixtures by independently heating them to 1100°C for different holding times of 0, 12, 24, and 36 minutes using a DHS furnace. Qualitative analysis of all SR-XRD patterns showed that only tetragonal zirconia (t-ZrO2) was present. The crystallite size of tetragonal zirconia ranged from 17 to 22 nm, depending on calcination holding time and CaO addition. Further analysis showed that the tetragonality (c/a) parameter remained relatively constant over the 36-minute holding time. However, the introduction of CaO led to an insignificant reduction in tetragonality, averaging 0.292%.
Characterization of the structure, morphology, and optical properties of titanium dioxide thin film deposited by spray pyrolysis technique for self-cleaning glass
Authors: Shabrina N. , Salsabila N. K. , Sudarsono S. , Yudoyono G.
Published: June 2024

The research in material science has actively pursued the creation of self-cleaning materials, especially for windows. Titanium dioxide (TiO2) is considered a promising substance for developing hydrophilic self-cleaning surfaces due to its photocatalytic activity. In this research, TiO2 nanoparticles were synthesized using TiCl3 as the precursor and co-precipitation as the experimental method in order to obtain anatase phase. The nanoparticles, then, was deposited by spray pyrolysis technique with different spraying time; 1, 2, 3, and 4 minutes and different types of TiO2 nanoparticles—synthesis and commercial—as the primary variations. TiO2 thin film was formed using ethyl cellulose as binder and isopropyl alcohol as solvent. The synthesized TiO2 nanoparticles and deposited thin film were, then, characterized using XRD, Maud software, UV-Visible Spectrophotometer, optical microscope, and SEM. The higher band gap energy value of TiO2 thin films was obtained with the average of 3.746 eV and 3.744 eV for TI(S) and TI(C), respectively, as a result of ethyl cellulose composition on the thin film. The thin film was categorized as hydrophilic.
Evaluation of Effective Doses of Radiation and Risk Factors in Thorax-Testing CT Scans of Patients with Lung Cancer Cases
Authors: Nasori Nasori , Putri Fadhilah Syifa H. , Farahdina Ulya , Hartanti Aditya Surya
Published: June 2024

Human organs have a certain dose tolerance to receive X-ray radiation, one of which can be received from radiodiagnostic radiation using a CT scan. The aim of this research is study to estimate the effective dose received by CT scan thorax patients then compare it with the Dose Limit Value (DLV) advised by the Nuclear Energy Regulatory Agency (BAPETEN). An estimated effective dose value can be created by calculating the dosage that an organ got from radiation during irradiation using a CT scan. IndoseCT v20b software and manual calculations using empirical tissue weight factors are used in this study to estimate the effective dose received by CT scan thorax patients. This estimated effective dose is then compared with the Dose Limit Value (DLV) advised by the Nuclear Energy Regulatory Agency (BAPETEN) for CT scan thorax patients. The effective dose also can be used to identify cancer risk factors as well as organs at risk in the chest cavity. The basic patient data for this study, including the computed tomography dose index vol (CTDIvol) and dose length product (DLP) values, were collected through observation. Then, on the basis of patient data from a thorax CT scan, data processing was done using the IndoQCT and IndoseCT v20b software programs as well as manual calculations utilizing empirical tissue weight factors. According to this information, the patient who received the greatest effective dose according to calculations made manually and using the IndoseCT program was 38.61 mSv and 35.75 mSv. The results of this study show that the both effective dose value from the two calculation results is still below the DLV recommended by BAPETEN so it is acceptable and considered safe for patients. The thymus gland, heart, and trachea-bronchi are the three organs that receive the highest effective dose values, which increases the possibility of damage after CT scan of the thorax in patients.
Software Design for Radial and Angular Directional Magnetic Field Measurement System of DECY-13 Cyclotron
Authors: Kurniawan I , Wibowo K , Puspitasari A J , Diah F I , Mulyani E
Published: June 2024

The Research Center for Accelerator Technology (PRTA) is currently developing the DECY-13 cyclotron in Yogyakarta for an energy level of 13 MeV. A critical component of the cyclotron is the magnet system, which is essential for deflecting and focusing the particle beam. Achieving isochronous criteria is of utmost importance in the design of this magnetic system. To ensure compliance with these criteria, a magnetic field mapping system has been developed consisting of two main component: mechanical system and control and instrumentation system (CIS). The mechanical system was developed in 2021 and in 2022, the focus shifted to the design of CIS. The CIS design involves four key stages: hardware identification, determination of operation procedures, and identification of main parameters. Following these stages, the operation flowchart and Human-Machine Interface (HMI) are created. Subsequently, the testing phase includes assessing the angular, radial, and auto-mapping movements. The test results revealed several errors in the movement, attributed to mechanical system malfunctions. Despite these challenges, the software’s basic functions meet the requirements for driving the mechanical system of the DECY-13 cyclotron. Addressing and rectifying the identified errors in the mechanical system is crucial for optimizing the overall performance of the DECY-13 cyclotron.
Tetrad formalism in the solution of spherically symmetric spacetime in general relativity
Authors: Wulandari Nadya E. S. , Subagyo Bintoro A. , Rahmani M. H.
Published: June 2024

Spherically symmetric solutions in general relativity are the most fundamental solutions to the Einstein field equation. The first exact solution of the Einstein field equation is the spherically symmetric solution given by the Schwarzschild metric, as easily found in any standard textbook on general relativity. The FLRW (Friedmann-Lemaitre-Robertson-Walkers) metric is another spherically symmetric solution of Einstein’s equation describing the standard model in Cosmology. The standard approach to solving Einstein’s equations is by considering the metric. However, we can also adopt a tetrad-based method or tetrad formalism. We review these two solutions by the tetrad formalism as an alternative approach. In addition, we give some more cases, including the cosmological constant and the Taub-NUT metric.
Understanding the Theoretic Study of Alkali Metal (Sodium, Na) Properties from Ab Initio Calculations
Authors: Enaroseha Omamoke O. E. , Apanapudor Joshua S. , Oyibo Obed , Oho Michael O.
Published: June 2024

We applied the first-principles calculations and examined the phonon dispersion, electronics band structure and mechanical properties of sodium. The usefulness of this method has been applied in determining the attribute of several metallic elements. Our results show that, the potential origin of the phonon oscillations arises from the existence of Fermi surface which emanates from the long range charge density. For Density of state, we observed sharp rise which is attributed to the conductivity of the Sodium electrons which combine both the s and p type electrons from Helium, hence the energy bands are fairly densely clustered and to some degree parallel. The calculated result of the heat capacity show a successive increase with raising temperatures starting from 0K and suddenly dropped to zero after attaining its peak at 300K. In general, the obtained results agrees with other theoretical and experimental data discussed in the literature.
Methane (CH4) Detection System Using The TGS2611 Sensor and MQ-4 Sensor
Authors: Ainur Rahma Mellynia , Suweni Muntini Melania , Sugriwan Iwan
Published: June 2024

This research focused on cow dung digesters as measurement samples, utilizing the TGS2611 and MQ-4 sensors, both known for their affordability. The objective was to develop a low-cost gas sensor system for monitoring methane gas concentrations through a straightforward web-based data acquisition platform. The DHT11 sensor was employed to measure air temperature and humidity. The electronic sensor circuit in this research utilized a voltage divider circuit. Testing the performance of the low-cost gas sensor involved integrating it with an anaerobic digestion system. For both the TGS2611 and MQ-4 sensors, the graph illustrating the relationship between sensor voltage (volts) and methane gas concentration (ppm) formed a logarithmic or non-linear pattern. The measurement range for the system was around 4700 ppm to 6300 ppm for TGS2611 and 4000 ppm to 5100 ppm for MQ-4. The sensor sensitivity was determined as 0.5433 Volts/ppm for TGS2611 and 0.5639 Volt/ppm for MQ-4. The TGS2611 sensor exhibited a higher response to changes in methane gas concentration, while the MQ-4 sensor successfully detected methane gas within its designated range. Interestingly, the TGS2611 sensor accurately detected methane gas concentrations above its specified range. The gas sampling procedure involved automatic gas sampling in a vacuum chamber for measurement, a strategy potentially enhancing sensor robustness. This research successfully amalgamated sensor advantages, circuit control, and data analysis to realize an economical yet reliable monitoring system.
Website-Based Monitoring System for Methane (CH4) Concentration, Humidity, and Temperature
Authors: Isnaini Nur , Suweni Muntini Melania , Sugriwan Iwan
Published: June 2024

The research developed a monitoring system that focuses on the development of a system and the acquisition of its readings into a simple website. This research was conducted in an effort to obtain data that can be used for managing methane gas pollution in the environment. Methane gas (CH
4) is a natural gas consisting of one carbon atom and four hydrogen atoms. Methane gas is one of the greenhouse gases that contribute to global warming, while humidity and temperature can increase or decrease methane gas productivity. Therefore, in this research, a monitoring system was created for methane gas concentration using TGS2611 sensor, humidity and temperature using DHT11 sensor through the creation of a chamber connected to test materials such as cow dung digesters and tofu wastewater as a source of methane gas production. The results obtained indicate that, in the development of the monitoring system as a measuring tool, it successfully detects the concentration of methane gas, humidity and temperature for each test material using calibration through characteristic equation V = 0,5591 ln(n) − 2,2657. For data acquisition in the form of methane gas concentration parameter readings by the TGS2611 sensor, humidity and temperature by the DHT11 sensor to the ESP8266 microcontroller to be displayed on the serial monitor, LCD, and the website that has been created in real-time. To display the data acquisition of the monitoring system, each component of the system is connected. Starting from software, hardware, and test materials. Data acquisition begins with sensor readings by ESP8266 through a program from Arduino IDE displayed on the serial monitor and LCD. Once connected to wifi or a hotspot and the data is successfully sent, the data will be checked by notepad++ and entered into the phpMyAdmin website database for storage. From this database. The data will then be displayed on the website that has been created in real-time. Additionally, humidity and temperature affect the increase and decrease in methane gas concentration productivity.
Comparison of Feature Histograms and Co-occurrence Matrix on Analysis of the Light Spectrum Effect for Identification of Surface Roughness with Speckle Images
Authors: Bustomi M A , Utama E W
Published: June 2024

Speckle imaging is a technique that can be used for digital image analysis. Speckle imaging technology essentially uses a laser to create a pattern of dots through the laser’s interference with an object. The advantage of speckle photography is that it is safe and does not require direct contact with the subject. In this study, speckle imaging techniques were used to analyze the surface roughness of objects. Speckle imaging techniques are used to investigate the influence of the choice of laser spectrum on the determination of the surface roughness of an object. For objects with rough surfaces, it comes in 80 sheets of coarse sandpaper and 2000 sheets of fine sandpaper. This study aims to compare the accuracy of identification results using Histogram Features and Co-occurrence Matrix Features when analyzing the influence of laser wavelength on object spot image identification. The research procedures included identifying rough objects, collecting point image data on rough surfaces using a series of experiments, pre-processing the point images, extracting features using histograms and co-occurrence matrices, and using a naive Bayes classifier. It includes determining surface roughness and performing comparisons between them. The resulting feature histogram and feature appearance matrix. This study shows that the use of Histogram Features and coexistence matrix features yields similar conclusions regarding the influence of the laser beam spectrum in determining the surface roughness of an object. The difference between Histogram Features and Co-occurrence Matrix Features lies in the pattern of detection results. Differences in the detection result patterns may be caused by differences in the characteristics of the Histogram Features and Co-occurrence Matrix Features of each speckle image used in the study. Although the detection result patterns of the Histogram Feature amount and the Co-occurrence Matrix feature amount are different, the accuracy of the detection result is equivalent. The similarity in the accuracy of the detection results may be caused by the similarity in the effectiveness of the two features in detecting the speckle image pattern.
Preliminary Study of Resonance Systems States in Surface Plasmon Resonance Systems
Authors: Faza R. A. , Chalimah S. , Sudarsono S. , Yudoyono G.
Published: June 2024

Resonance between light and collective electrons is known as Surface Plasmon Resonance or SPR. The development of SPR-based sensors can generate the use of a Kretschmann configuration prism. Otto configuration dielectric medium between prism and gold thin film. For the Kretschmann configuration, a gold thin film between the prism and dielectric medium. So, this research focuses on the use of the Kretschmann configuration in the SPR system because the setup of the half-cylindrical prism is less complicated than using the Otto configuration. In this research, we compare the reflectance of an uncoated half-cylindrical prism and a half-cylindrical prism coated with a gold thin film to see the resonance effect. The beam reflected by the back surface of the prism was detected using a photodiode sensor (OPT-101, Texas Instruments). The photodiode sensor is connected to Arduino Uno, and the voltage reading results are processed with Arduino Ide software. Adjusting the He-Ne laser light’s angle of incidence and the prism’s angle of impact 30° – 50°. The experimental results show that the TIR (total internal reflection) phenomenon occurs in half-cylindrical prisms without a gold coating. Meanwhile, in the half-cylindrical prism coated with gold, a resonance phenomenon can be seen, this case, at a particular angle of incidence, can be detected through a reduction in the beam’s intensity of the reflected light. The photodiode sensor detects a decrease in voltage value, which indicates an intensity decrease, which was originally 4.34 volts to 2.52 volts when the incident angle of the light beam was 45°.
The evaluation of Indigofera seed production and quality in different environments
Authors: Sari E D , Abdullah L , Kumalasari N R , Fanindi A
Published: June 2024

Seed production and quality are pivotal factors in the success of Indigofera cultivation as forage crop for livestock. This study aims to evaluate the seed production and quality of Indigofera in different environments of Seed Production Unit (SPU). Seven distinct SPU’s, namely BPPIB-TSP Bunikasih, BBIB Singosari, BPTU-HPT Denpasar, BPTU-HPT Pelaihari, BPTU-HPT Sembawa, BBPTU-HPT Baturraden, and CV Cahaya Baru Semarang selected as the observed locations. Environmental data pertaining to elevation (m a.s.l.), annual rainfall (mm/year), temperature (°C), humidity (%), and light intensity (Lumen-hour) were collected for each unit. Seed production parameters were seed yield (g) and seed weight (g per 1,000 seeds). Seed quality parameters encompassed water content (%), purity (%), and viability (%). The analysis in this study involved assessing the mean differences in these parameters through the application of analysis of variance (ANOVA). The result showed the seed production and quality were diverse across SPUs, with BPTU-HPT Sembawa and CV Cahaya Baru Semarang demonstrating outstanding seed production, while BPTU-HPT Pelaihari maintains high-quality standards. The highest positive correlation emerged between elevation and water content (r = 0.72), highlighting the influence of altitude on the moisture content of seeds. The strongest negative correlation was observed between temperature and water content (r = -0.76), emphasizing the role of temperature in drying seeds.
Analysis of added value and market share in porang value chain in wonogiri regency
Authors: Handayani S M , Widadie F , Rahayu E S , Irianto H , Setyowati  , Sundari M T , Rachmanto F
Published: June 2024

Porang is an agricultural commodity with high economic value recently. However, the high economic value does not have much impact on farmers due to low added value and market share. This study aimed to analyse the added value and market share of the porang value chain in Wonogiri regency. Cost, and marketing margin were examined to determine each actor’s added value and market share in the chains of Porang in Wonoiri. Data was collected through interviews with all chain actors, such as farmers, rural collectors at the village and district level, wholesalers, and processors. The results show that the highest added value and market share of Porang is in a processor, with 97.88% and 95.14%, respectively. While the lowest one is in farmers, there are no added value activities, and the market share is 5.84%. There is a big gap in added value and market share among actors in the Porang value chains. Strategies to upgrade velue chains at farmer level are to upgrade governance structures, added value activities, and network structures.
Potential of nitrogen-fixing and phosphate-solubilizing rhizobacteria from indigenous dryland flora
Authors: Maulida E I , Cahyono O , Yunus A. , Dewi W S
Published: June 2024

Rhizobacteria inhabit the root area of flora and can act as nitrogen fixers and phosphate solvents. This study aims to determine the potential of indigenous dryland rhizobacteria for fixing dissolved nitrogen and phosphate in an artificial medium. Rhizobacteria isolated from rice varieties Inpago 12 and understorey (Eleusine indica L.) have the potential for nitrogen fixation and phosphate solubility. The outcome of morphological observations obtained two types of NFB isolates from each isolate source, while PSB obtained three types of isolates. The highest total NFB population was in the T1J1 isolate at 1.46 x 105 CFU/g, while the highest PSB was in the U2P2 isolate at 8.2 x 104 CFU/g. Further study is needed to determine the potential of rhizobacteria from rice varieties Inpago 12 and understorey (Eleusine indica L.) in dryland for quantitative nitrogen fixation and phosphate solubility.
Exploration and Characterization of Johar (Cassia siamea) Accession as a Source of Raw Material for Antimalaria Drug
Authors: Widiyastuti Yuli , Subositi Dyah , Haryanti Sari , Mujahid R , Siswanto Usman
Published: June 2024

Johar is a medicinal plant belonging to the Fabaceae family, often planted as a roadside shade. Empirically, johar leaf is used for traditional medicine, including malaria, itching, scabies, diabetes, fever, wounds, and tonic. The active compound responsible for the antimalarial activity, Casiarine A, has been successfully isolated and identified from the johar leaf. The availability of johar plants with a high content of Casiarine A as the active compound is very necessary. For this reason, exploration and characterization of johar were carried out to provide superior accessions with high biomass production and bioactive compound content. The research was conducted in an exploratory accession of the plants from certain Central and East Java areas. The sample plants were morphologically characterized, and productivity tests were investigated, including the simplicia dry yield, total extract content, and phytochemical profile. The results showed that 13 johar accessions were obtained from 13 growing regions with similar morphological characters. The main differences observed were in the size, color, and shape of the leaves. The growth location affects dry yield, total extract content, and phytochemical profile. Based on the measured parameters, Johar accessions were grouped into lowland, midland, and highland clusters according to their growth locations.
Pedological Factors, Classification, Physical-Chemical Properties and Management Strategies of Inceptisols in the Boca Formation of Temanggung, Cetral Java, Indonesia (Study: Horticultural Land Management)
Authors: Fauziah L
Published: June 2024

The purpose of this research is to see the development of soil and management strategy of the boca formation in the Temanggung, Central Java, Indonesia. The boca range in Temanggung are hills located in Danurejo, Central Java, which are part of the old Sumbing mountain formation. This area is thought to be an intrusion area of cracks from the old Sumbing mountain, located at the foot of the mountain between Sumbing and Sindoro mountains. The boca formation is located at 705.9 m above sea level (m asl), in general the Boca formation consists of breccia, andesite, anglomerate and tuff. Vegetation that grows in the boca range includes bamboo and cotton. Soil genesis in the boca range has not yet reached an advanced stage of development characterized by the formation of an argillic horizon. The observed soil shows a diagnostic horizon, the cambic horizon. The soil acidity level (pH 5-6.5), falls into the slightly acidic class, with a texture dominated by geluhan. Based on the data obtained through field survey and laboratory analysis, the soils in the boca range are classified into Inceptisols based on USDA, Cambisols based on PPT and Cambisols based on WRB with ustic regime.