bluuebunny/crossref_metadata_2025 huggingface dataset:
Edge-Based Viscous Method for Mixed-Element Node-Centered Finite-Volume Solvers
Authors: Liu Yi , Diskin Boris , Nishikawa Hiroaki , Anderson William K. , Nastac Gabriel C. , Nielsen Eric J. , Walden Aaron , Wang Li
Published: September 2023

A novel, efficient, edge-based viscous (EBV) discretization method has been recently developed and implemented in a practical, unstructured-grid, node-centered, finite-volume flow solver. The EBV method is applied to viscous-kernel computations that include evaluations of mean-flow viscous fluxes, turbulence-model and chemistry-model diffusion terms, and the corresponding Jacobian contributions. Initially, the EBV method had been implemented for tetrahedral grids and demonstrated multifold acceleration of all viscous-kernel computations. This paper presents an extension of the EBV method for mixed-element grids. In addition to the primal edges of a given mixed-element grid, virtual edges are introduced to connect cell nodes that are not connected by a primal edge. The EBV method uses an efficient loop over all (primal and virtual) edges and features a compact discretization stencil based on the nearest neighbors. This study verifies the EBV method and assesses its efficiency on mixed-element grids by comparing the EBV solution accuracy and iterative convergence with those of well-established solutions obtained using a cell-based viscous (CBV) discretization method. The EBV solver’s memory footprint is optimized and often smaller than the memory footprint of the CBV solver. An EBV implementation of a nonlinear extension of the Spalart–Allmaras turbulence model, SA-neg-QCR2000, is also presented and verified. The SA-neg-QCR2000 model is used for simulating turbulent corner flows. Multifold speedup is demonstrated for all viscous-kernel computations, resulting in significant reduction of the time to solutions for several benchmark mixed-element-grid computations, including simulations of subsonic flows around a hemisphere–cylinder configuration and a NASA juncture-flow model, a supersonic flow through a long square duct, and a hypersonic, chemically reacting flow around a blunt body.
Dynamic Stall Control for a Vertical-Axis Wind Turbine Using Plasma Actuators
Authors: Yu Haocheng , Zhang Ao , Zheng Jianguo
Published: September 2023

Dynamic stall is a major challenge for vertical-axis wind turbines (VAWTs) as it negatively impacts the aerodynamic performance of VAWTs, resulting in a reduction in net power output from the turbines. This study explores the use of alternating current dielectric barrier discharge plasma actuators for controlling dynamic stall on a VAWT. The flow control process is resolved using a two-dimensional unsteady Reynolds-averaged Navier–Stokes equations simulation with a Reynolds stress turbulence model adopted. The macro-effect of the plasma discharge on mean flow is modeled by an empirical body force model. The detailed flow actuation procedure is simulated. Numerical results show that the flow control process is dominated by the spanwise vortices, which result from the interaction between the plasma discharge and separated flow. The spanwise vortices not only prevent the development of a leading-edge separation bubble into a dynamic stall vortex, but also suppress the flow separation at the trailing edge. The application of plasma forcing has been found to greatly enhance the aerodynamic performance of the turbine in terms of the moment coefficient and averaged power coefficient of the turbine blades. Furthermore, we examine how the positioning of the plasma actuators and the freestream wind velocity affect flow control. The optimal actuation location is determined, and the plasma actuators are seen to be able to substantially enhance the net power output of the blades at all freestream speeds.
Large-Eddy Simulation for Slowly Oscillating Turbulent Flow Using Harmonic Balance Approach
Authors: Iwamoto Yuma , Teramoto Susumu , Okamoto Koji
Published: September 2023

Herein, harmonic balanced large-eddy simulation (HB-LES) is proposed for the efficient high-fidelity simulation of slowly oscillating turbulent flows such as cascade flutter in turbomachinery or transonic airfoil buffet. The harmonic balance method for unsteady Reynolds-averaged Navier–Stokes simulation is introduced to large-eddy simulation (LES), utilizing the difference in timescales between the periodic flow and the turbulent fluctuations. Considering their nonlinear mutual interaction, periodic flow and turbulent fluctuations are computed by iterating short-time LES and the harmonic balance method. The HB-LES is applied to the analysis of a Stokes boundary-layer problem at the Reynolds number based on the Stokes boundary-layer thickness of 1790. The characteristics and evolution of the turbulent structures near the wall are consistent with those observed in the results of conventional LES. Both the phase-averaged periodic component and the turbulence statistics show good quantitative agreement with the experimental results and conventional LES. Furthermore, nonlinearity of the periodic component caused by the mutual interaction between turbulent fluctuations and the periodic component is reproduced as a rapid increase in wall-shear stress. The proposed HB-LES demonstrated approximately a 10-fold improvement in computational efficiency.
Pulsating Heat Pipe Experiments for Microgravity Sounding Rocket Tests
Authors: Guessi Domiciano Kelvin , Krambeck Larissa , Mantelli Marcia Barbosa Henriques , Alonso Betancur Arboleda Luis
Published: September 2023

Two flat plate diffusion-bonded pulsating heat pipes (PHPs) for the thermal management and heat dissipation of concentrated heat flux in electronics applications, such as aboard satellites and spacecraft, were specially developed for future tests aboard a sounding rocket in microgravity conditions. Both devices contain 26 channels with round cross sections, one with ultrasharp lateral grooves in the evaporator. Two heat sinks were tested: a water-cooling bath for the thermal characterization of the PHPs, and a copper box with a phase change material (dodecahydrate bibasic sodium phosphate) to be qualified as the heat storage for future microgravity tests. Water was used as the working fluid. The best filling ratio (relative to the total internal volume of the PHPs) was experimentally determined to be 50%, for which the devices presented the earliest startup and the lowest thermal resistance, around 0.033°C/W for the grooved PHP. This research proposes an efficient and alternative cooling method, the phase change material storage, to be used as a heat sink in future microgravity tests. Also, the microgravity effect on the thermal performance of such PHPs can be assessed by comparing the present results with future microgravity data obtained in an experimental module aboard a sounding rocket.
Utilization of Activated Carbon/Magnesium(II) Composites in Decreasing Organic Materials
Authors: Ullica Dheasi Rani , Zaharah Titin Anita , Silalahi Imelda Hotmarisi
Published: September 2023

This study aimed to determine the characteristics, adsorption capacity, and isotherm of the adsorbent AC/Mg(II) composite in decreasing organic matter in peat water. Activated carbon was produced from empty fruit bunches of oil palm containing high levels of lignocellulose. Carbon was synthesized through the carbonization process and then activated with CH3COONa. The activated sample was composited with magnesium nitrate hexahydrate through an in-situ method under alkaline conditions using NaOH. The adsorbent AC/Mg(II) composite that had been prepared was characterized using FTIR, showing the presence of Mg-O bonds at the absorption wave number of 403.12 cm-1. The results showed that the moisture content of the adsorbent was lower compared to activated carbon, namely 1.30%. Furthermore, the best mass was 2 g AC/Mg(II) with an adsorption of 2.26 mg/g and an organic matter adsorption percentage of 14.41%. Furthermore, the optimum contact time was 15 minutes with an adsorption of 2.42 mg/g and a percentage of 17.15%. The mechanism occurring in the AC/Mg(II) composite with peat water organic matter followed the Langmuir isotherm equation, which formed a monolayer. The equation gave R2, adsorption capacity (Qo), and adsorption constant (k) values of 0.9994, 0.2340 mg/g, and 0.0047, respectively.
Learning Obstacle Materi Pengukuran Sudut Siswa Kelas IV di SD Negeri 32 Palembang
Authors: Lorenza Dela , Fuadiah Nyiayu Fahriza , Surmilasari Nora
Published: September 2023

Penelitian ini dilatarbelakangi oleh adanya hambatan belajar (Learning Obstacles) yang dialami siswa di SD Negeri 32 Palembang. Jenis hambatan belajar yang menjadi fokus dalam penelitian ini adalah hambatan ontogenik, hambatan didaktis, dan hambatan epistemologis. Metode penelitian ini adalah deskriptif kualitatif dan instrumennya berupa tes pada materi pengukuran sudut, analisis materi, analisis bahan ajar, analisis RPP dan wawancara. Hambatan belajar diperoleh dengan menganalisis hambatan belajar yang dialami siswa dilihat dari 4 (empat) yaitu tes diagnostik hambatan belajar, aspek analisis bahan ajar, analisis RPP, dan wawancara dengan guru kelas dan siswa. Hasil penelitian ini menemukan hambatan belajar dikategorikan menjadi 3 jenis, yaitu hambatan ontogenik, hambatan didaktis, dan hambatan epistemologis. Jenis hambatan belajar yang dialami siswa adalah kurangnya penguasaan konsep dasar materi dan kesulitan dalam memecahkan masalah yang merupakan hambatan ontogenik, hambatan didaktis, terkait dengan perangkat pembelajaran yang digunakan guru, dan hambatan epistemologis, yaitu keterbatasan konteks pemahaman yang dimiliki siswa
Pengembangan Modul Pembelajaran Matematika Materi Statistika Kelas IV Sekolah Dasar
Authors: Cahyanti Windi Dwi , Fuadiah Nyiayu Fahriza , Surmilasari Nora
Published: September 2023

Penelitian ini bertujuan untuk mengembangkan modul pembelajaran matematika materi statistika kelas IV yang valid, praktis dan untuk mengetahui keefektifan modul yang telah dikembangkan. Berdasarkan hasil wawancara didapatkan bahwa peserta didik tidak dapat memahami materi secara mandiri harus dengan penjelasan dari pendidik yang secara berulang-ulang, dan pendidik menyatakan bahwa hasil belajar peserta didik masih rendah, sehingga perlu dikembangkannya bahan ajar untuk mendukung proses pembelajaran yaitu modul. Penelitian ini termasuk dalam penelitian dan pengembangan, mengacu pada pengembangan model 4-D yang dibatasi menjadi 3-D dengan tiga tahapan yaitu (1) Define (pendefinisian). (2) Design (perancangan). (3) Develop (pengembangan). Penelitian bertempat di SDN 195 Palembang. Subjek penelitian yaitu peserta didik kelas IV SD. Pengumpulan data dilakukan dengan instrumen penilaian validasi modul, instrumen penilaian kepraktisan (guru), instrumen penilaian kepraktisan (peserta didik), dan data hasil tes soal peserta didik. Hasil penelitian menunjukkan bahwa modul yang dikembangkan mendapatkan presentase 96,09% dengan kategori ’’sangat valid’’. Hasil penilaian kepraktisan (guru) mendapatkan 92,64% dengan kategori ’’sangat praktis’’. Hasil uji skala kecil mendapatkan presentase 90,41%. Hasil tes soal peserta didik mendapatkan presentase 88,88% dengan kategori ’’sangat efektif’’. Sehingga dapat disimpulkan bahwa modul pembelajaran matematika materi statistika kelas IV SD termasuk ke dalam modul yang valid, praktis, dan efektif
Upaya Meningkatkan Kualitas Produk Dengan Pendekatan Fault Tree Analysis (FTA) Pada UPT X Di Kabupaten Magetan
Authors: Toni Toni , Zainal Muttaqin Aan , Isnaini Wiladanul
Published: September 2023

AbstrakUPT X berlokasi di Kabupaten Magetan memproduksi kulit yang memiliki beragam mesin yang digunakan untuk proses penyamakan. Banyak industri kulit menengah (IKM) yang bergerak dibidang penyamakan dan produk kulit dari Jawa Timur, khususnya dari wilayah Magetan dan sekitarnya yang mengelola kulit di UPT X  yang bertugas untuk mengelola bidang pelayanan kulit dan sebagai bahan baku pembuatan sepatu dan tas yang terbuat dari kulit. Penelitian ini mengunakan metode FTA (Fault Tree Analysis) untuk mengidentifikasi masalah kualitas produk dan menggambarkan kondisi yang menyebabkan kejadian cacat pada produksi. Berdasarkan penelitian yang dilakukan  di bulan November 2021 sampai April 2022  didapatkan nilai terbesar dari presentase  rework terdapat pada  mesin fleshing dengan bobot sebesar  22%. Untuk cacat mesin fleshing adalah sobek pada permukaan kulit yang disebabkan oleh beberapa faktor seperti rusaknya pada mata pisau, mesin tidak bekerja secara maksimal, terdapat goresan pada permukaan kulit, bolong atau sobek, lingkungan produksi yang menyengat, suara kebisingan, suhu panas dan kurangnya pencahayaan, rekomendasi perbaikan perlu adanya maintenance secara berkala untuk mengurangi cacat pada produk.
 

Kata Kunci : Kualitas, Penyamakan Kulit, , FTA

 

Abstract

UPT X is located in Magetan Regency, producing leather which has a variety of machines used for the tanning process. Many medium-sized leather industries (IKM) engaged in tanning and leather products from East Java, especially from the Magetan area and its surroundings, manage leather at UPT X which is tasked with managing the leather service sector and as raw material for making shoes and bags made of leather. This study uses the FTA (Fault Tree Analysis) method to identify product quality problems and describe the conditions that cause defects in production. Based on research conducted in November 2021 to April 2022, the largest value of the percentage of rework is found in the fleshing machine with a weight of 22%. For fleshing machine defects, there are tears on the skin surface caused by several factors such as damage to the blade, the machine does not work optimally, there are scratches on the skin surface, holes or tears, a stifling production environment, noise, heat and lack of lighting, repair recommendations need regular maintenance to reduce product defects.

 

Keywords: Quality, Tannery, FTA
Development and Application of Hybrid AIMD/cDFT Simulations for Atomic-to-Mesoscale Chemistry
Authors: Song Duo , Bylaska Eric , Sushko Maria , Rosso Kevin
Published: September 2023

Many important geochemical and biogeochemical processes involve reactivity and dynamics in complex solutions. Gaining a fundamental understanding of these reaction mechanisms is a challenging goal that requires advanced computational and experimental approaches. However, important techniques such as molecular simulation have limitations in terms of scales of time, length and system complexity. Furthermore, among currently available solvation models, there are very few designed to describe the interaction between the molecular scale and mesoscale. To help address this challenge, here we establish a novel hybrid approach that couples first principle plane-wave density functional theory (DFT) with classical density functional theory (cDFT). In this approach, a region of interest described by ab initio molecular dynamics (AIMD) interacts with the surrounding medium described using cDFT to arrive at a self-consistent ground state. cDFT is a robust but efficient mesoscopic approach to accurate thermodynamics of bulk electrolyte solutions over a wide concentration range (up to 2 molar concentrations). Benchmarking against commonly used continuum models of solvation such as SMD, as well as experiment, demonstrates that our hybrid AIMD/cDFT method is able to produce reasonable solvation energies for a variety of molecules and ions. With this model, we also examined solvent effects on a prototype S$_N$2 reaction of the nucleophilic attack of a chloride ion on methyl chloride in solution. The resulting reaction pathway profile and the solution phase barrier agree well with the experiment, showing that our AIMD/cDFT hybrid approach can provide insight into the specific role of solvent on the reaction coordinate.
Tribological Behaviour of Aluminium-Copper-Cullet Metal Composite
Authors: Hussain Nuhu Awwal , Jikan SUZI Salwah , Asman SALIZA , Badarulzaman NUR AZAM , Tijjani ABDULLAHI , Khalid MUNIRA
Published: September 2023

An Aluminium composite metal, Al-Cu-CP was fabricated from recycled raw materials. The composite was fabricated by means of stir casting method due to its simplicity and economic worth. The composite and the unreinforced Al were both analysed for chemical and mechanical properties. The Al-Cu-CP metal composite produced has shown appreciable level of wear resistance and corrosion resistance in artificial seawater (3.5 g/L NaCl) and allowed to stand for 96 h at room temperature. Different loads were considered for the wear resistance tests, 5 N, 10 N, 15 N and 20 N while 150 rpm, 250 rpm, 350 rpm and 450 rpm were the speeds selected for the adhesive wear resistance test. Improved properties were observed after heat treatment of the Al-Cu-CP metal composite. The heat treated composite was more resistant to corrosion than the untreated composite and it has been confirmed that the corrosion resistance of the materials under study has direct relationship with the immersion period. When the maximum load was applied to the three (3) sets of the samples (unreinforced, treated and treated composites), severe degrees of wear manifested on their various surfaces. Optical images from morphological analysis revealed that wear severity was highest on the surface of the unreinforced matrix, followed by the untreated metal composite and the heat-treated composite was found to be the least affected. Due to these enhanced properties of the Al-Cu-CP metal composite, it could be recommended where high strength with light density product is required such as automobile brake shoes and brake disc as a result of its upgraded mechanical properties.
A multimodal view at cancerous liver tissue by chemical bioimaging and image segmentation strategies
Authors: Kronenberg Katharina , Werner Julia , Seeba Marten , Rave Hennes , Linsen Lars , Steiger Katja , Jeibmann Astrid , Bohrer Peter , Paprottka Philipp Marius , Braren Rickmer Früdd , Lohöfer Fabian Karl , Karst Uwe
Published: September 2023

Six complementary biomedical imaging modalities are combined providing substantial correlation capabilities between optical, elemental and molecular tissue characteristics. Diseased rat liver tissue with hepatocellular carcinoma (HCC) was investigated, as liver cancer is a leading cause of tumor-related mortality. Bright field microscopy, autofluorescence microscopy and histological examination of hematoxylin-eosin-stained tissue displayed comprehensive optical tissue characteristics. Elemental imaging by non-destructive micro x-ray fluorescence (µXRF) and quantitative laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) revealed lower content for nine elements in HCC and lesions compared to the liver. Non-destructive quantum cascade laser (QCL)-based infrared microspectroscopy visualized higher lipid, protein, and nucleic acid content in the liver compared to HCC, and glycogen accumulations in lesions. Matrix-assisted laser desorption/ionization-trapped ion mobility spectrometry-mass spectrometry (MALDI-TIMS-MS) unveiled individual lipid distributions to characterize HCC, connective and adjacent liver tissue. Detailed image segmentation was facilitated by (bisecting) k-means clustering and interactive clustering using uniform manifold approximation and projection (UMAP) embeddings.
Asymmetric q-Gaussian functions to fit the Raman LO mode band in Silicon Carbide
Authors: Sparavigna Amelia Carolina
Published: September 2023

Previous studies (Sparavigna, 2023) have demonstrated the Tsallis q-Gaussian functions suitable for the analysis of Raman spectra. Here we consider two asymmetric forms of them, with the aim of further improving the fitting of Raman spectra. The first asymmetric form, that we are here proposing for the first time, is a generalization of the Breit-Wigner-Fano function. The other profile is that made by two different half q-Gaussian functions, chosen to fit the two sides of a Raman band. The case study that we will discuss in detail is that of the Raman LO mode of Silicon Carbide.
Indoor Air Quality Implications of Germicidal 222 nm Light
Authors: Barber Victoria , Goss Matthew , Franco Deloya Lesly , LeMar Lexy , Li Yaowei , Helstrom Erik , Canagaratna Manjula , Keutsch Frank , Kroll Jesse
Published: September 2023

One strategy for mitigating the indoor transmission of airborne pathogens, including the SARS-CoV-2 virus, is irradiation by germicidal UV light (GUV). A particularly promising approach is 222 nm light from KrCl excimer lamps (GUV222); this inactivates airborne pathogens and is thought to be relatively safe for human skin and eye exposure. However, the impact of GUV222 on the composition of indoor air has received little experimental study. Here, we conduct laboratory experiments in a 150 L Teflon chamber to examine the formation of secondary species by GUV222. We show that GUV222 generates ozone (O3) and hydroxyl radicals (OH), both of which can react with volatile organic compounds to form oxidized volatile organic compounds and secondary organic aerosol particles. Results are consistent with a box model based on known photochemistry. We use this model to simulate GUV222 irradiation under more realistic indoor air scenarios, and demonstrate that under some conditions, GUV222 irradiation can lead to levels of O3, OH, and secondary organic products that are substantially elevated relative to normal indoor conditions. The results suggest that GUV222 should be used at low intensities and in concert with ventilation, decreasing levels of airborne pathogens while mitigating the formation of air pollutants.
Predicting Poisson's Ratio: A Study of Semi-supervised Anomaly Detection and Supervised Approaches
Authors: Hammad Raheel , Mondal Sownyak
Published: September 2023

Auxetics are a rare class of materials that exhibit a negative Poisson's ratio. The existence of these auxetic materials is rare but has a large number of applications in designing exotic materials. We build a complete machine learning framework to detect Auxetic materials as well as Poisson’s ratio of non-auxetic materials. A semi-supervised anomaly detection model is presented which is capable of separating out the auxetics materials (treated as an anomaly) from an unknown database with an average precision of 0.64. Another regression model (supervised) is also created to predict the Poisson’s ratio of non-auxetic materials with an R² ≈ 0.82. Additionally, this regression model helps in finding the optimal features for the anomaly detection model. This methodology can be generalized and used to discover materials with rare physical properties.
Auger-Meitner and X-ray absorption spectra of ethylene cation: Insight from conical intersection dynamics
Authors: Nunes Cabral Tenorio Bruno , Pedersen Jacob , Barbatti Mario , Decleva Piero , Coriani Sonia
Published: September 2023

We present a theoretical investigation into the near-edge X-ray absorption fine structure and the Auger-Meitner decay spectra of ethylene and its cation. Herein, we demonstrate that our method, coupled with the nuclear ensemble approach, successfully reproduces the natural bandwidth structure of the experimental resonant Auger-Meitner decay spectra of ethylene, which is not very well reproduced within the Franck-Condon approximation. Furthermore, we have analyzed the Auger-Meitner decay spectra of the ethylene cation in the light of minimum energy conical intersection structures involving the two lowest cationic states (D1 and D0), providing valuable insights into the ultrafast D1/D0 relaxation dynamics. Our results suggest that Auger-Meitner electron spectroscopy can help elucidate the mechanism behind the initial 20 fs of the relaxation dynamics.
Thermo-/mechano-chromic Chiral Coordination Dimer: Formation of Switchable and Metastable Discrete Structure through Chiral Self-sorting
Authors: Takimoto Kazuyoshi , Shimada Takumi , Nagura Kazuhiko , Hill Jonathan P. , Nakanishi Takashi , Yuge Hidetaka , Ishihara Shinsuke , Labuta Jan , Sato Hisako
Published: September 2023

Although strong chiral self-sorting (e.g., sergeants and soldiers principle, majority rules) often emerges in extended covalent or supramolecular polymers, the phenomenon is generally weak in discrete assemblies (e.g., dimers, oligomers) of small molecules due to the lack of a cooperative growth mechanism. Consequently, chiral self-sorting has been overlooked in the design of switchable and metastable discrete supramolecular structures. Here we report a benzo[h]quinoline-based iridi-um(III) complex (Ir) with helical chirality at its metal centre, which forms preferentially a homochiral dimer and exhibits thermo-/mechano-chromism based on a monomer-dimer transformation. While a five-coordinate monomer is formed in ra-cemic or enantiopure Ir solution at 25 °C, a six-coordinate homochiral dimer complex is formed almost exclusively at low temperatures, with a higher degree of dimerization in enantiopure Ir solution. Estimation of dimerization binding constants (K) and thermodynamic parameters (ΔH and ΔS) based on variable temperature UV-Vis and 1H NMR spectra reveal a strong preference for homochiral dimerization (largest known value for coordination complex, Khomo/Khetero > 50) as a result of steric repulsions of peripheral alkyl chains in Ir heterochiral dimers. Notably, crystals of homochiral dimer are metastable, under-going a distinct colour change upon grinding (from yellow to red) due to mechanical cleavage of coordination bonds (i.e., a dimer to monomer transformation). Ir dimerization involves both strong homochiral self-sorting preference and connected thermo-/mechano-chromic behaviour, leading to emergence of dynamic functionality based on the rational design of discrete chiral assemblies.
Benchmarking Density Functional Theory Methods for Metalloenzyme Reactions: The Introduction of the MME55 Set
Authors: Wappett Dominique , Goerigk Lars
Published: September 2023

We present a new benchmark set of metalloenzyme model reaction energies and barrier heights, which we call MME55. The set contains ten different enzymes, representing eight transition metals, both open and closed shell systems, and system sizes of up to 116 atoms. We use four DLPNO-CCSD(T)-based approaches to calculate reference values, against which we then benchmark the performance of a range of density functional approximations with and without dispersion corrections. Dispersion corrections improve the results across the board, and triple-ζ basis sets provide the best balance of efficiency and accuracy. Jacob's ladder is reproduced for the whole set based on averaged mean absolute (percentage) deviations, with the double hybrids SOS0-PBE0-2-D3(BJ) and revDOD-PBEP86-D4 standing out as the most accurate methods for the MME55 set. The range-separated hybrids ωB97M-V and ωB97X-V also perform well here and can be recommended as a reliable compromise between accuracy and efficiency; they have already been shown to be robust across many other types of chemical problems as well. Despite the popularity of B3LYP in computational enzymology, it is not a strong performer on our benchmark set, and we discourage its use for enzyme energetics.
The Expectations of Others
Authors: Garcia-Lembergman Ezequiel , Hajdini Ina , Leer John , Pedemonte Mathieu O. , Schoenle Raphael S.
Published: September 2023

Based on a framework of memory and recall that accounts for social networks, we provide conditions under which social networks can amplify expectations. We provide evidence for several predictions of the model using a novel dataset on inflation expectations and social network connections: Inflation expectations in the social network are statistically significantly, positively associated with individual inflation expectations; the relationship is stronger for groups that share common demographic characteristics, such as gender, income, or political affiliation. An instrumental variable approach further establishes causality of these results while also showing that salient information transmits strongly through the network. Our estimates imply that the influence of the social network overall amplifies but does not destabilize inflation expectations.
The role of a discount rate in a transmission mechanism and its influence on the deposits market
Authors: Maistrenko O.
Published: September 2023

The article focuses on the analysis of the dynamics of the discount rate as a key monetary policy tool. It examines how the discount rate, through the transmission mechanism, influences fluctuations in interbank interest rates and the bank deposit market. The study examines the indicators of Ukraine's banking sector over the past 5 years, considering the impact of external shocks such as the COVID-19 pandemic and large-scale armed aggression by Russia. These factors have resulted in inflation and interest rate growth in developed countries, a stronger US dollar, decreased business activity, and negative business expectations, all of which significantly impact Ukraine's small open economy. Consequently, the National Bank of Ukraine has implemented measures to stimulate creditworthiness, support entrepreneurship during lockdowns, and ensure access to profitable long-term financing, while also maintaining stability in the banking system during crises. The study analyzes the effects of the regulator's policy of increasing the discount rate and curtailing anti-crisis measures to curb inflation, which have had positive consequences during the most challenging crisis periods and the initial stages of economic recovery. It also highlights macroeconomic measures and restrictions imposed by the central bank to stabilize the economy in the face of a full-scale Russian military invasion, including state interventions to offset costs in priority areas of the economy. Despite the ongoing impact of tight monetary policy on the domestic market, a potential slowdown in inflation, stabilization of the exchange rate, and the funding market may contribute to the revival of the interbank market, bank lending, and potential revision of the discount rate and/or dollar exchange rate in the long term. The study further conducts a simulation of the balanced level of the discount rate using the classic Taylor equation, indicating the possibility of revising and gradually relaxing tight monetary conditions in 2023. However, it suggests that the rate reduction may be moderate, around 0.5-1.5 percentage points in the short term and 2 to 4 percentage points in the medium term. Overall, the study underscores the importance of the discount rate as a monetary policy tool and its implications for Ukraine's banking sector, given the external shocks and challenges faced by the country.
Possibilities and prospects for airport revenue recovery by applying international strategies of economic development
Authors: Kim T. , Kryvtsov O.
Published: September 2023

The global air transportation market has tremendously changed over the past three years. Worldwide quarantine restrictions complicated the process of aeronautical communication both at the domestic and international levels. Lockdown resulted in a sharp decrease in the volume of world passenger traffic - a vital source of airport revenues. This article studied global airport revenues and classified airport services by type and revenues according to the sources of their receipt. The structure of aeronautical and non-aeronautical revenues was given, and the most common airport charges were characterized. The state and forecasts of world passenger air transportation volume during 2015-2025 and the impact of the COVID-19 pandemic on them were studied in this article. In particular, the way it redistributed shares of non-aeronautical revenues with an increase in the share of rental revenues. Attention to the impact of a full-scale Russian invasion of Ukraine on the global aviation industry was paid. The current forecasts for the recovery of the global air transportation market were studied. Analysis of the current state of aeronautical and non-aeronautical airport revenues allowed to identify possible strategies for increasing their volume under post-pandemic aeronautical market recovery conditions. Among the possible measures for airports, the following were highlighted: implementation of dynamic pricing based on demand and airport workload, using the diversification strategy for organizing income sources with a focus on non-aeronautical services and air cargo transportation. The importance of greening economic activity in the long term was noted to ensure the investment attraction of airports.
Sharing economy and insurance in the hospitality industry
Authors: Kalaitan T. , Danchevska I.
Published: September 2023

The purpose of the article is to study the peculiarities of insurance in the shared use sector of the hospitality industry, taking into account the specifics of this sector of the economy. To achieve this goal, the authors sets the following tasks: (1) to determine the specifics of the sharing economy; (2) to assess current trends and prospects for the development of the hospitality industry market in the sharing sector; (3) to study foreign experience of insurance in the field of short-term rental housing through online sharing platforms. The study found that the sharing economy is growing rapidly, gaining significant market share in some sectors. Experts predict that global revenue in this area will grow to USD 335 billion in 2025. An analysis of statistical data has shown that the shared-use sector in the tourist accommodation sector in some EU regions not only recovered in 2022 but even exceeded the figures for 2019. This trend is quite logical, as during financal crisis, people tend to save money and choose budget holiday options. The analysis showed that user protection (health and safety, asset security, quality issues) is not fully guaranteed in the sharing economy. Standard home insurance policies in the US, for example, do not provide adequate coverage for paying guests in a private home. In addition, they do not protect homeowners from claims from guests. A positive example of how to address insurance issues in the sharing economy is the approach taken by Airbnb, which, in cooperation with insurance companies, provides protection for hosts and their guests. This experience will be useful for Ukrainian practice in the post-war period, given that in difficult economic conditions, demand in the sharing economy accommodation sector is growing significantly.
Historical aspects of the profit category formation and its modern interpretation for enterprises of the hotel and restaurant business
Authors: Vyslobodska H. , Kalaitan T.
Published: September 2023

The study purpose is (1) to examine the historical aspects of the economic category “profit” formation, (2) to determine the modern characteristics of the category "profit" and (3) of the profit formation features for enterprises of restaurant and hotel business. A systematic review of scientific literature on the topic was used to study the historical aspects of the profit category formation and of its current state. In order to assess the profit economic importance as a basis for the state development, time series analysis was used, as well as a graphical method based on Excel. Modelling was applied to assess the impact of factors on profit formation in the hotel and restaurant business. The results of the analysis of the scientific literature referred to the topic of the study show the ambiguous attraction of the profit category in the historical aspect of its development. Profit is a multifaceted and complex category that has constantly evolved from antiquity to modern times. The meaning of profit is evidenced by the fact that it is the main source of financial resources at the micro- and macro- levels. Income tax is important for formation of state budget revenues. The analysis of profit tax revenues and its share in Ukraine’s consolidated budget shows that the profit tax share in the revenues structure of the Ukraine consolidated budget fluctuates over the past 7 years within the range of 6–11%. Hotel and restaurant businesses belong to the service sector. At the same time, restaurant enterprise accomplishes the functions of production, trade, and service provision. An analytical study of the influence of factors on the formation of profit requires a qualitative analytical model that would take into account the specified specifics. Such a model should be based on a marginal approach.
Treasury single account, revenue generation and utilization among nigerian universities - A pre–post assessment
Authors: Tomori Abdulfatai Adeyinka
Published: September 2023

This study empirically examined the impact of Treasury Single Account (TSA) on revenue generated and its utilization in the federal government-owned universities. University of Ilorin was used for the study. The objectives of the study was to find out the level of fund accumulation and utilization at the University of Ilorin before TSA implementation, and find out the level of fund accumulation and utilization at the University after TSA implementation. Two null hypotheses were formulated for the study. Secondary data was utilized for the study. Total fund and its utilization at the University of Ilorin for the period 2012 – 2017 were collected from the Unilorin Annual Reports. The data collected was divided into two, i.e. pre and post TSA period, that is 2012 to 2014 and 2015 to 2017, respectively. A pre-post analysis was carried out using SPSS version 20. Findings show that TSA implementation has improved revenue generation at the University of Ilorin. Further findings revealed that University's revenue utilization improved after TSA implementation from N6, 691,451,094.41 billion to N8, 928,707,239.14 billion. Since, the P-value of both hypotheses is less than the significance level (0.05), the two null hypotheses could not be accepted. It was recommended that government at all levels should prioritize universities education funding. In addition, Universities must find a way to increase their internally generated funding levels and finally, Nigerian Universities should take advantages of TSA policy to enhance their development by key into every aspect of the policy drive.
Budgetary control at mangalore chemicals and fertilizers ltd.: An empirical study during FY 2011-12
Authors: Ravinarayana K. S.
Published: September 2023

The study conducted on the budgetary control at MCF to examine the following points. In MCF the annual operational plan was prepared for ascertaining the budgeted performances with actual performances. The actual sales of the company is increased from 2007-08 to 2011-12 as compared to budgeted sales. The study is based on the data made th available by Mangalore Chemicals and Fertilizers Limited. The analysis was conducted for a period of 6 weeks from 10th December 2012 to 19th January 2013. The study is based on secondary data, collected from the information's provided by the company and by interview with the executives of the company. The t-test was used to evaluate the accuracy of the budget by comparing budgeted figures with actual figures. From the study it can be concluded that budgetary control is treated as one of the better techniques for minimizing cost and maximizing profit in Mangalore Chemicals and Fertilizers Limited.
Sugar palm starch (Arenga pinnata) modification using microwave and
acetylation: effect of moisture content and microwave power on physicochemical
characteristics
Authors: Hehamahua Z.N. , Aziezah E.A. , Supriyadi  , Ningrum A. , Ardhi A.
Published: September 2023

Sugar palm starch (Arenga pinnata) can be utilized for food and non-food products. The
natural properties of native starch are high viscosity, fast retrogradation problems,
unstable to heat and acid, and low paste resistance. Therefore, modifying sugar palm
starch is necessary to improve its physicochemical characteristics. Microwave and
acetylation are reported to be effective modification methods. In this research,
modification using a microwave was carried out at 13%, 18%, 23%, and 28% moisture
content, with a power of 200 W, 300 W, and 399 W. In general, increasing moisture
content and microwave power could decrease starch, amylose content, and swelling power
while solubility increases. The higher power applied reduced the starch granule size and
changed the pasting properties. All the treatments in this research did not change the
functional groups of the starch. The results showed that the starch with a moisture content
of 13% and a microwave power of 300 W could most effectively reduce the granule size
and swelling power. Subsequently, this condition opted for a combination modification
method with acetylation. The combination of acetylation and microwave modification on
sugar palm starch significantly decreased the starch and amylose content, swelling power,
solubility, and granule size and changed the pasting properties of the starch. However, the
combination of acetylation and microwave treatment had different effects on starch
content and solubility compared to the single acetylation modification in particular.
Overall, this result has demonstrated that dual modification of sugar palm starch could
improve the limitation of its native characteristics in terms of granule size, swelling
ability, gelatinization temperature, and retrogradation stability, which might be
advantageous for specific purposes of food processing.
Planthopper population monitoring in Malaysian rice granary as a pre-requisite
in releasing new rice varieties
Authors: M. Mohd Fitri , I. Zairul Azrin
Published: September 2023

Brown planthopper (BPH) and green leafhopper (GLH) are among the major insect pest in
Malaysian rice cultivation. The existence of a high population with a serious infestation of
these insects can result in low rice yield for the farmers. The importance of these insect
pests is among those taken into account in the development of new rice varieties. Thus, in
the assessment of new rice varieties in the field trial plot, BPH and GLH population
monitoring activities were carried out at nine selected rice fields for two seasons of rice
cultivation. The results showed that there were significant differences between the
location of trial plots for BPH and GLH populations in the fields. Seberang Perai, Pulau
Pinang had the highest BPH population (mean, 1.37 hoppers) and Pendang, Kedah had the
lowest (mean, 0.27 hoppers). The GLH population is the opposite, with Seberang Perai,
Pulau Pinang having the lowest population (mean, 0.05 hoppers) and Pendang, Kedah
having the highest population (mean, 1.80 hoppers). The insect monitoring conducted in
Seberang Perak, Perak for the main season of rice cultivation recorded a high BPH
population and exceeded the economic threshold level (ETL). It’s almost the same in
Sungai Besar, Selangor for the off-season of rice cultivation. In Pendang, Kedah, the GLH
population is high and exceeds the economic threshold level (ETL) during the main
season of rice cultivation. The presence of BPH and GLH populations varies by location
as well as the rice planting season.
دراسات حول المنظمات العامة المستدامة
Authors: Khudair Al-Kubaisy Amer
Published: September 2023

تناول هذا الكتاب استدامة المنظمات العامة، التي تُعَدّ السبيل إلى ترجمة إستراتيجيات وخطط وبرامج التنمية المستدامة، فالاستدامة أصبحت اليوم "البرادايم العلمي والعملي" الذي تطرحه الأمم المتحدة من خلال منظماتها ومؤتمراتها واتفاقاتها الدولية.
وحرص الكتاب على رسم خارطة طريق للمنظمات العامة العربية يمكن أن تتحول عبرها من واقعها التقليدي إلى مستقبل واعد من خلال الاستدامة.
وجاء الكتاب في عشرة فصول:
تناول الفصل الأول خصائص المنظمات المستقبلية وأدوارها التي تميزها عن المنظمات التقليدية، وبيان مبررات التحول نحو استدامتها، كما استعرض أهم المداخل والآليات والنظريات والعمليات، التي يمر خلالها هذا التحول.
وتناول الفصل الثاني القيادات الإدارية والتنظيمية ودورها في تحويل المنظمات التقليدية إلى منظمات مستدامة.
وتناول الفصل الثالث دور الجامعات في تحقيق التنمية المستدامة مع بيان متطلبات التعليم المستدام.
وخُصِّص الفصل الرابع للمستشفيات المستدامة.
وتناول الفصل الخامس المنظمات الأمنية ودورها التنموي المستدام.
 واستعرض الفصل السادس السياحة المستدامة.
وتناول الفصل السابع مفهوم الوقف الخيري، مستعرضًا أنواع الوقف وخصائصه ودوره في تنشيط برامج التنمية البشرية والاجتماعية، وإسهامات الوقف السعودي.
وتناول الفصل الثامن منظمات المجتمع المدني ودورها.
واستعرض الفصل التاسع مفهوم المدن المستدامة بوصفها البيئة التي تحتضن جميع المنظمات على اختلاف مجالاتها وتخصصاتها.
وعرض الفصل العاشر بعض التجارب الرائدة، مثل: تجربة المملكة العربية السعودية في الاستفادة من الطاقة الشمسية، وتجربة دولة الإمارات العربية المتحدة في توجهها نحو الاقتصاد الأخضر وخفض الغازات الدفيئة. كما تناول هذا الفصل تجربة الأردن في مجال التنوع الحيوي وإعادة تأهيل المناطق الساخنة. وأيضًا تجربة الجزائر في إنشاء الصناديق الوطنية للرسوم البيئية وفي السياحة المستدامة. وتمت الإشارة إلى البرامج المستدامة التي طُبِّقت في بعض الدول المتقدمة في هذا المجال وأهمها: كندا وألمانيا وماليزيا والصين.
وفي خاتمة الكتاب عُرِضت بعض المنطلقات والمفاهيم التي يمكن الاسترشاد بها من أجل تحويل المنظمات العامة والمدنية والخاصة من طابعها التقليدي ومن أهدافها التي رُسِمَت لها، إلى أهداف الألفية الثالثة.
مواجهة الحملات الإعلامية المضادة عبر مواقع التواصل الاجتماعي
Authors: Abdulrahman Makki Um Alsaad
Published: September 2023

سعى هذا الكتابُ إلى إبراز دور الجهود الأمنيَّة المبذولة في التصدِّي للحملات الإعلاميَّة للتنظيمات الإرهابيَّة عبر مواقع التواصل الاجتماعي، التي أصبحت مسرحًا لارتكاب مختلف الجرائم السيبرانيَّة، وذلك بحكم نقل التنظيمات الإرهابيَّة نشاطها إلى الإنترنت للترويج لبرامجها وأفكارها وأعمالها.
وبيَّن الكتابُ أيضًا خطورة الجرائم الإلكترونية (المستحدثة)، ومتطلبات وآليات مواجهتها، لاحتواء خطورة تلك الظاهرة، بغرض التصدي لأعمال التنظيمات الإرهابية، وما تقوم به من نشاطات تخريبية، تستهدف النيل من مؤسسات الدول، وتُلحِق الضرر بالأفراد.
وجاء الكتاب في خمسة فصول:
جاء الفصل الأول مدخلاً للدراسة. 
وتناول الفصل الثاني مفهوم وخصوصية الجريمة السيبرانية والمواجهة الأمنية.
وتناول الفصل الثالث الحملة الإعلامية المضادة: المفهوم، الإستراتيجية، الآليات، من خلال التعريف بمفهوم الحملة الإعلامية بصفة عامة وخطوات إدارتها، وأهدافها، ومميزاتها، ومقوماتها، وأنواعها. كما تناول هذا الفصل أيضًا المفهوم الرئيس في الكتاب وهو (الحملة الإعلامية المضادة)، والإستراتيجية المعتمدة من طرف الجهة القائمة بالحملة، وأغراض الحملة، وجمهورها، ووسائلها، وآثارها، ومنطلقاتها ومرتكزاتها، كما أوضح آليات مواجهة الحملة الإعلامية المضادة.
وبيَّن الفصل الرابع استخدام (فيسبوك) في إدارة الحملة الإعلامية المضادة، من خلال التعريف بمواقع التواصل الاجتماعي عمومًا، وإيضاح التطور المسجل في عدد مستخدميها.
واستعرض الفصل الخامس، الذي يُمَثّل الدراسة التطبيقية ذات الطبيعة التحليلية، آليات المواجهة الأمنية (فيسبوكيًّا) للحملة الإعلامية المضادة، وذلك بناء على الرسائل والمضامين التي أدرجها كل من جهازي الأمن الجزائري والفرنسي على صفحتيهما (الفيسبوكية)، باعتبارهما يمثلان المجال (المكاني) للدراسة. كما تناول الفصل تحديد آليات المواجهة الأمنية للحملات الإعلامية المضادة عبر صفحتي (فيسبوك) الخاصتين بجهازي الأمن الجزائري والفرنسي، من خلال تحليل كل صفحة على حدة، من ناحيتي الشكل والمحتوى.
وأخيرًا عرض الكتاب الخاتمة والنتائج.
ومن أهم النتائج:
- التدقيق في هويات المستخدمين أمر ضروري؛ للتصدي لجرائم انتحال الصفة، وسرقة البيانات، والحسابات بهويات مستعارة؛ لمواجهة مختلف الإشكاليات المثارة حول الهوية الرقمية والأمن المعلوماتي.