bluuebunny/crossref_metadata_2025 huggingface dataset:
How Simulation and Modeling Lower Prototype and Startup Costs
Authors: Luellen Joseph
Published: September 2024

From concept and design to production readiness, introducing a new product or service can be expensive. Because of the lower cost of smart technologies, it is now possible to validate designs with less rounds of prototyping and testing. This leads to savings in the design phase, improved product quality, and less materials and energy being used to bring the product or service to market. The sum total of these savings’ lower startup costs.
Film Properties of Si-DLC Intermediate Layer with Different Gas Compositions and DLC with C2H2 Gas
Authors: Okano Atsuki , Nishimoto Akio
Published: September 2024

Diamond-like carbon (DLC) coatings, which improve wear resistance and extend component service life, have gained considerable research attention as an approach for conserving limited resources. The DLC coating is a highly functional film with high hardness and excellent low-friction, wear-resistance, and corrosion-resistance properties; however, it has high residual stress and low adhesion between the substrate and the film. Existing studies have focused on using DLC containing metallic elements (Me-DLC) as an intermediate layer to minimize residual stress, thereby improving adhesion. Si-DLC is deposited using a mixture of hydrocarbon gases, such as methane (CH4) and acetylene (C2H2), and silicon gases, such as tetramethylsilane (TMS: Si(CH3)4), H, and Si, to form the DLC coating. The composition, hardness, Young’s modulus, and friction coefficient of the film can be controlled by changing the composition of the gas mixture. This study investigated the effect of the flow rate ratio of source gases (CH4 and TMS; C2H2 and TMS) on the properties of the DLC film when Si-DLC is deposited as an intermediate layer on austenitic stainless steel SUS304 using plasma-enhanced chemical vapor deposition. The coating time was adjusted to ensure that the thicknesses of the Si-DLC layer and DLC film were 1.0 and 0.2 μm, respectively, under both conditions. The results demonstrated that the durability of the DLC film improved and adhesion decreased with a decrease in the TMS ratio in the Si-DLC intermediate layer. Durability improved and adhesion decreased when C2H2 was used as the source gas, as compared to when CH4 was used.
Advancements in Steel Hardening Distortion Control Using a 4-Dimension High-Pressure Gas Quenching (4DQ) System
Authors: Hart Tom
Published: September 2024

It is well known that distortion has and continues to present a challenge to the heat treater when hardening steel. However, recent advances in quenching technology are improving the opportunity for improved distortion control. 4 Dimension High-Pressure Gas Quenching (4DQ) is a unique gas quenching process that uses both quenching chamber design and part motion to minimize distortion during the quenching process. To understand 4DQ’s potential, the challenges of traditional batch quenching and press quenching techniques will be explored, emphasizing issues such as geometric distortion, residual thermal stresses, non-uniform microstructure transformation, safety, environmental, and handling concerns.

In contrast, 4DQ is a process that enhances quenching uniformity and minimizes distortion by use of a specialized cooling chamber. Within the chamber it provides three-dimensional (3D) quenching by enveloping the part at specific areas with cooling gas while introducing the fourth dimension (4D) of part rotation during quenching that further optimizes quench uniformity. 4DQ gives the ability to “engineer” the quenching process by controlling quench pressure, gas velocity, gas manifold design, table rotation, table oscillation, and time-dependent gas flow. The system’s flexibility allows users to customize the quenching process for reduced distortion, repeatability, and precise accuracy. A case study on hypoid hears and coupling sleeves will demonstrate the effectiveness of the 4DQ system in minimizing distortion and achieving dimensional consistency. Results illustrate the system’s advantages over traditional quenching methods in terms of quality, repeatability, and cost-effectiveness.

Considering the challenges of steel hardening processes, the 4DQ system has the potential to be a transformative solution for achieving enhanced quenching uniformity and reduced heat treatment distortion in manufacturing scenarios.
Post-Process Heat Treatment of Tool Steel Dies Repaired by Laser Direct Energy Deposition
Authors: Pellizzari Massimo , Zhao Zhao , Tronconi Edoardo , Perini Matteo , Amirabdollahian Sasan , Deirmina Faraz
Published: September 2024

Mold repair is a viable strategy for saving energy and reducing CO2 emissions. Papers in the literature show that repairing a limited damaged area of the mold instead of producing a new one is becoming increasingly attractive, especially considering the latest European and international regulations introduced with the green deal. In this paper, the authors are pleased to present some preliminary results related to the repair of AISI H13 tool steel molds by Laser-Directed Energy Deposition. Steel blocks (20 x 55 x 100 mm3), previously tempered at 435±10 HV, were machined to reproduce the material removal of the damaged part of the mold. Subsequently, the region was repaired by L-DED using commercial H13 powder. The process parameters were optimized to obtain a defect-free welded area. Since the microstructure of the deposited tool steel consists of hard (730±10 HV) and brittle (7 J Charpy impact toughness) martensite, a series of post-process heat treatments were performed at different temperatures to restore a hardness compatible with that of the base steel. However, this goal was only partially achieved due to the different tempering behavior of L-DED-deposited and bulk H13 steel. In particular, the tempering temperature had to be limited to avoid softening of the base steel. In the best case, double tempering at 620 °C resulted in a toughness recovery of up to 42 J. Thermal fatigue tests showed better resistance to crack propagation after tempering, as evidenced by the shallower penetration depth compared to the as-built material.
Hot Ductility of 70/30 Copper-Nickel Alloys
Authors: Caruso Matthew , Crowley Samuel , Frame Lesley
Published: September 2024

Ductility dip cracking (DDC) is a detrimental solid-state cracking phenomenon that can occur during welding of copper-nickel (Cu-Ni) alloys used in naval vessels. The presence of these cracks has several deleterious effects, including reduced fatigue life and increased susceptibility to corrosion. The mechanism of DDC remains highly debated and understudied, especially in material systems outside of Ni-Cr-Fe alloys. The predominant mechanisms that have been proposed include: 1. Grain boundary sliding, 2. Precipitate-induced strain, and 3. Impurity element segregation. In the present body of research, thermal-mechanical testing over a wide range of strain rates and temperatures was performed using a Gleeble 3500. Both flow-stress and fracture morphology of wrought 70/30 Cu- Ni are considered. Following fracture, microstructural analyses using both scanning electron microscopy and optical microscopy were conducted to observe and quantify intergranular cracking and fracture surface features. Results show a strong correlation among fracture morphology, ductility, and temperature.
Effects of Thermal Processing History on Microstructure and Local Hardness in a Bainitic TRIP Steel
Authors: Shields Mitchell H. , Speer John G. , Findley Kip O. , Haddad Fares
Published: September 2024

Carbide free bainitic microstructures can be developed via different thermal processing routes, and the details affect the scale and morphology of the microstructural constituents. In this study, bainitic microstructures are formed by either a controlled cooling process or an austempering process to evaluate the relationship between microstructure and mechanical properties in a 0.2C - 2Mn - 1.5Si - 0.8Cr steel containing small amounts of Nb, Ti, B, and N, and the results are compared to a 4140 steel processed via quenching and tempering. The resulting microstructures are characterized with scanning electron microscopy. When compared to microstructures produced via austempering, microstructures produced with a controlled cool exhibit an increased variety of transformation products, specifically regarding size and distribution of martensite-austenite constituents within a lath-like bainitic ferrite matrix. Nanoindentation testing shows that different transformation products exhibit significantly different local hardness. In all (primarily) bainitic conditions tested for these materials, the martensite/austenite constituent exhibits the highest hardness, followed by the lath bainitic ferrite/retained austenite constituent. Granular bainite and coarse bainitic constituents exhibit the lowest relative hardness in the conditions where they are observed.
Effect of Quench Rate on PFZ Width in 7xxx Aluminum Alloys
Authors: MacKenzie D. Scott
Published: September 2024

The effect of quench rate on the width of precipitate free zone was examined in aluminum alloys 7075 and 7050. It was determined that at quench rates greater than 60°C/sec., vacancy depletion dominated. At slower quench rates, it was determined that solute depletion dominated the precipitate free zone. The critical vacancy concentration for precipitation was established as a function of quench rate.
Overview of Professor Tatsuo Inoue’s Contributions to the Field of Heat Treatment Simulation
Authors: Arimoto Kyozo
Published: September 2024

Prof. Tatsuo Inoue passed away on September 23, 2023, at the age of 83. He held a professorship at Kyoto University from 1983 to 2003 and made significant contributions to the theory of heat treatment simulation, which is now widely used. His theory was reported at an international conference in Linkoping, Sweden in 1984. Fundamental equations in his theory cover metallurgical coupling effects caused by changes due to phase transformation, temperature, and inelastic stress/strain as well as carbon diffusion during the carburizing process. Prof. Inoue designated these effects as “metallothermo- mechanical coupling”. Software applying his theory was presented at ASM International’s 1st International Conference on Quenching and the Control of Distortion in 1992, where its advanced nature was recognized. In 1994, Prof. Inoue published a paper on the application of heat treatment simulation to the quenching of Japanese swords, revealing changes in temperature, curving, microstructure, and stress/strain in their model during the traditional quenching process. In 2017, he published “The Science of Japanese Swords” with Sumihira Manabe, a swordsmith, to communicate his specific achievements to the general public.
True Gas Sensing in Vacuum and Atmosphere, Where RGAs Fail to Go
Authors: Brindley Joe , Daniel Benoit , Massey Kieran , Bellido-Gonzalez Victor , Monaghan Dermot , Wingens Thomas
Published: September 2024

The nature of vacuum based processing is inherently problematic as the vacuum quality can be adversely affected by a range of effects that can contaminate the environment. If the level of such contamination exceeds acceptable limits, the quality of the produced parts will fall below standard and result in lower productivity and higher costs. The larger and more complex the vacuum processing chamber, the higher the probability of contamination, and the bigger the disruption to efficient production. Prediction and measurement of contamination within a vacuum is possible by residual gas analysis (RGA). Residual gas analysis can detect the presence and quantity of the gaseous species present, and as such is the most universal tool available to combat the difficulties experienced whilst vacuum processing. Traditionally vacuum residual gas analysis is performed by quadrupole mass spectrometry. A new method of residual gas analysis based upon remote plasma optical emission spectroscopy has overcome the drawbacks of using quadrupole based RGAs on large scale industrial vacuum systems. This remote plasma type of RGA operates over a wide range of vacuum pressures and is highly robust which guarantees continuous operation and avoids maintenance. The data provided can be used for smart digital control and monitoring of most forms of vacuum processes and ultimately ensures improved productivity.
Modeling Alloy Carbide Formation and Coarsening during High-Temperature Tempering of Ferrium C64 Steel
Authors: Meyer Jason , Li Zhichao (Charlie)
Published: September 2024

High-alloy steels, like Ferrium C64, are used in powertrain components due to their corrosion resistance and high temperature resistance properties. These steels undergo a tempering temperature that is well above traditional steel, and during this process alloy carbides or compounds form, increasing the materials hardness, mechanical strength, and high temperature resistance properties. In the early stages of tempering, softening occurs due to the formation and coarsening of iron carbide, followed by a hardening as the alloy elements combine to form nano-scale dispersoids. These alloy carbides block the path of dislocations in the grain, strengthening the material. At longer tempering times or high temperatures, the coarsening of these alloy carbides and compounds can cause softening. A predictive material model for the high-tempering response of steels is needed to ensure peak hardening properties are met. For a robust heat treatment model, the material response for every step of the process needs to be modeled. These material properties include austenitization rates and thermal expansion during heating, carbon diffusivity and saturation limits for carburization, phase transformation rates and thermal contraction rates per phase during cooling and quenching, deep-freeze kinetics for further martensitic transformation, tempering kinetics for formation of the tempered martensite phase, and carbide kinetics for formation, coarsening, and size. Additionally, mechanical properties of each phase as a function of carbon need to be defined to ensure the proper mechanical response during and after heat treatment. After the material model is developed it can be used to design and optimize the high-temperature tempering process for any part using the same material.
Effects of Surface Induction Hardening on the Torsional Fatigue Performance of Previously Carburized Modified 4121 Steel
Authors: Tanous Benjamin H. , Findley Kip O. , Cryderman Robert L. , Moor and Emmanuel De , Farago Jim , Fantauzzi Chris , Marshall Brian , Goldstein Robert C.
Published: September 2024

Carburizing and induction hardening are two surface heat treatments commonly used to increase wear resistance and fatigue performance of steel parts subject to cyclical torsional loading. It was originally hypothesized that performing an induction surface hardening heat treatment on parts previously carburized could provide further increased fatigue life, however initial torsional fatigue results from previous work indicated the opposite as the as-carburized conditions exhibited better torsional fatigue strength than the carburized plus induction surface hardened conditions. The aim of this work is to further elucidate these torsional fatigue results through metallography and material property characterization, namely non-martensitic transformation product (NTMP) analysis, prior austenite grain size (PAGS) analysis, and residual stress vs depth analysis using x-ray diffraction (XRD).

A carburizing heat treatment with a case depth of 1.0 or 1.5 mm and an induction hardening heat treatment with a case depth of 0, 2.0, or 3.0 mm were applied to torsional fatigue specimens of 4121 steel modified with 0.84 wt pct Cr. The carburized samples without further induction processing, the 0 mm induction case depth, served as a baseline for comparison. The as-received microstructure of the alloy was a combination of polygonal ferrite and upper bainite with area fractions of approximately 27% and 73% respectively.

The only conditions that exhibited NMTP were the as-carburized conditions. These conditions also exhibited larger average PAGS and higher magnitude compressive residual stresses at the surface compared to the carburized plus induction hardened conditions. The compressive residual stresses offer the best explanation for the trends observed in the torsional fatigue results as the conditions with NMTP present and larger PAGS exhibited the best torsional fatigue performance, which is opposite of what has been observed in literature.
Surface Modification of Copper by Resin Particle Peening Treatment
Authors: Nambu Koichiro , Kunimatsu Ryuji
Published: September 2024

Copper is expected to be increasingly used in electric vehicle components because of its high electrical and thermal conductivity. On the other hand, copper has the disadvantage of low fatigue strength compared to structural members such as steel and aluminum alloys. Therefore, the peening treatment is used in this study to increase the strength of copper. However, the projectile used in conventional peening treatments is much harder than copper, which may lead to deterioration of surface properties. Therefore, we decided to use a resin particle peening treatment that uses soft resin particles. For the projectile material, we used particles made from crushed walnut, apricot, and peach, which are natural material particles. Ceramic particles were used for comparison. Hardness measurements revealed that the near-surface hardness increased even when resin particles were used. In addition, compressive residual stresses were observed on the surface. Fatigue tests revealed that the fatigue strength improvement effect was higher than that of nontreated materials or hard particles. These results indicate that the resin particle peening treatment is an effective method for strengthening copper.
Innovation in AlSl M2 Steel through Additive Manufacturing and Induction Heat Treatment
Authors: Nachazelova D. , Koukolikova M. , Brazda M. , Urbanek M.
Published: September 2024

Additive manufacturing is increasingly used in a variety of applications. Directed Energy Deposition (DED) technology using powder feedstock enables the production of materials in combinations that would be very problematic using conventional technologies. DED is a technological process where the fed material is melted directly at the desired location using a laser beam. The research described here deals with the additive manufacturing and subsequent induction heat treatment of a functional deposited layer of M2 high-speed steel. Induction treatment has the advantage that only the functional layer of the component can be heat treated without affecting the base material. It is therefore possible to heat treat a combination of completely different materials with different properties without degrading the base material. Hardness values reached 950 HV (68 HRC) both after additive manufacturing and after additive manufacturing and induction treatment. Induction heat treatment of the deposited M2 layer ensured removal of traces of the original melt pools produced by the additive manufacturing. Investigation of the microstructure and mechanical properties of M2 tool steel after induction heat treatment produced by DED highlights its potential for high performance tooling and machining applications.

The main objective of this research is to improve the final properties and tool life of forming tools when the tool is made of less expensive low-alloy steel and its functional layer is made of M2 high speed steel using additive manufacturing technology.
A Novel Oxygen Free Ferritic Nitro Carburizing Process
Authors: Gundel P.H.
Published: September 2024

Anti-wear, anti-galling and scratch resistance are well-known properties associated with FNC processes. The marked demand for expansion of the scope of processes in equipment available, has led to the development of tailored FNC process for application to low alloyed steel, and alloyed steel. The process had to be oxygen free, as the equipment is also applied in expanded austenite processes for corrosion resistant alloys. Utilizing our mass flow controller equipped furnaces the tight control of the parameters is possible resulting in high repeatability and a consistent compound layer formation.

The process has been applied to a number of different alloys, showing good results for unalloyed steels and steels in quenched and tempered condition.
Who is the Bearded Man and the Young Boy Standing Next to Him?
Authors: Amir H. Zekrgoo
Published: September 2024

The SMNA Library is custodian to an interesting manuscript that contains two interesting poetry books bound in a single leather binding. The manuscript is both exciting and – in almost every instance – misleading! Its peculiar features are riddle-like, confusing and alerting at the same time. The volume is incomplete from both ends; the beginning of the first part (Leylī va Majnῡn) is missing, and so is the end of the second part (Khosrow va Shīrīn), and several sections in between. And whatever remains also is not in right arrangement. And to these major imperfections, I may add a consistent terrible handwriting all-through! One may therefore conclude that the volume is of no significance. Yet, a careful assessment of the text, illustrations, seal impressions, marginal writings, and doodling sketches, will bring the manuscript to a new light of literal, historical, social, and artistic significance.
Industrial robotics in Russia under the conditions of sanctions
Authors:   Russian State Scientific Center for Robotics and Technical Cybernetics, Nikolaev Alexander
Published: September 2024

The article in question is a brief analytical review based on the materials of open publications of the state of indus-trial robotics in Russia on the eve and after the introduction of sanctions by the West related to the implementation of Special military operation. Despite the lack of official information, the estimated quantitative characteristics of the domestic industrial robotics market in the specified period are given and the main factors influencing its devel-opment are listed with appropriate conclusions.
Accumulation of Cd and Pb in soils irrigated with sewage and non-sewage water in Prayagraj, India
Authors: VERMA JEETENDRA , MANI DINESH , SAHU VIPIN , SHUKLA DEVI PRASAD , VISHWAKARMA HIMANCHAL , KUMAR MANOJ , OJHA RUPESH KUMAR
Published: September 2024

Unmanaged agricultural fields and the extended usage of sewage irrigation water can raise the concentration of heavy metals (Cd and Pb) in the soil, turning it into barren soil. The study was conducted during 2022-23 at four sewage and non-sewage irrigated sites in Prayagraj namely Naini, Baxibandh, Rasulabad and Draupadi Ghat. The representative soil samples were taken at depths of 0-15, 15-30, 30-45 and 45-60 cm. Di-acid mixture method was used for the estimation of heavy metals (Cd and Pb) in the soil sample by AAS (Atomic Absorption Spectrophotometer) (AAnalyst600, Perkin Elmer Inc., MA, USA). Contamination factor (CF) and enrichment factor % (EF) of different sites showed various results which fulfill the basic criteria of present and future prospective of research. The highest concentration of Cd and Pb was found in the surface layer (0-15 cm) of sewage and non-sewage irrigated sites at Naini i.e., Cd (4.46±0.42 and 1.05±0.08 mg/kg) and Pb (6.53±0.62 and 1.18±0.12 mg/kg) respectively. The lowest concentration of Cd and Pb was found in the sub-surface layer (45-60 cm) of sewage and non-sewage irrigated sites at Draupadi Ghat i.e., Cd (1.02±0.09 and 0.16±0.01 mg/kg) and Pb (1.68±0.12 and 0.18±0.01 mg/kg) respectively. The concentration of heavy metals cadmium (Cd) and lead (Pb) declined with soil profile depth in both sewage and non-sewage irrigated soils. The long-term persistence of heavy metal contamination in soil can lead to severe issues; therefore, regular monitoring of sewage-irrigated soils is necessary to minimize heavy metal pollution.
Enhancing cadmium phytoremediation in contaminated soil using sunflower (Helianthus annuus L.) with EDTA and vermicompost amendments
Authors: KUMAR MANOJ , MANI DINESH , SAHU VIPIN , VERMA JEETENDRA , OJHA RUPESH KUMAR , PATEL SURAJ
Published: September 2024

The study hypothesis posits that EDTA, an effective chelating agent, can effectively mobilize cadmium from soil, augmenting the sunflower's natural ability to absorb and sequester heavy metals. Concurrently, vermicompost, rich in organic matter and beneficial microorganisms, enhances soil health and supports plant growth, thereby fortifying the sunflower's phytoremediative potential. The pot experiment was carried out as an overall completely randomized design (CRD) at the Sheila Dhar Institute (SDI) experimental farm, University of Allahabad, Prayagraj, in the Kharif season during the years 2023-2024. Plants were cultivated in pots with soil (5 kg) that contained varying concentrations of Cd (0, 15, 30, and 50 mg/kg), vermicompost (0 and 10 g/kg), and EDTA (0 and 2.5 mmol/kg). Plants were also cultivated in containers with clean soil (T1) as control treatment. For analyzed heavy metal (Cd) in plants with a tri-acid mixture (15 ml) containing concentrations of HNO3, H2SO4, and HClO4 in 5:1:2 ratios, use the Atomic Absorption Spectrophotometer (AAS). The result showed that the combined Treatment (T3) pot of application of Cd 0+ EDTA (2.5 mmol/kg) and vermicompost (10 g/kg) was the maximum dry biomass (14.43 g/pot) of the sunflower plant. While the maximum dose combined treatment (T12) application of Cd 50 mg/kg+ EDTA 2.5 mmol/kg and vermicompost 10 g/kg is greater than before, the maximum accumulation of Cd in the shoot and root of Helianthus annuus L. by shoot 37.16% and root 31.16%, respectively as compared to the control treatment pot Cd-50. The results indicate that the combined application of EDTA and vermicompost significantly increased cadmium uptake by sunflowers compared to untreated controls, demonstrating their synergistic effect in improving phytoremediation efficiency.
Stochastic models for time complexity of computing tasks: II. Description of interaction with databases
Authors: Borisov A. V. , Ivanov A. V.
Published: September 2024

The paper contains the second part of an investigation devoted to the design of the mathematical models for the execution time of user tasks carried out on the virtual calculating nodes. We provide the performance of the proposed model for the description of the data processing fulfilled in the databases. As a testbed for stress testing, we choose a prototype of the anonymization system of the passengers’ personal data. There are stochastic models describing two types of user tasks: personal data anonymization procedure and calculation of the sample statistical characteristics. The paper contains a detailed description of the stress test planning and fulfillment for both models. The obtained mathematical models developed by the real data demonstrate high performance.
On the optimal control function diagrams in the problem of the movement of a platform with oscillators
Authors: Kayumov O. R.
Published: September 2024

We consider the problem of the time-optimal movement of a rigid body moving translationally along a horizontal straight line and carrying n-linear oscillators. The only control force is applied to the platform and is limited in magnitude, there is no friction. The system is transferred from a state of rest to a specified distance with vibration damping. The evolution of optimal control functions depending on the distance of movement is investigated. A general approach to constructing a visual diagram reflecting such evolution is proposed. To do this, a geometric interpretation of the necessary optimality conditions is used as properties of an auxiliary “control” curve in n-dimensional space. Numerical examples of constructing diagrams of optimal control functions for a platform with three oscillators are given.
Analisis Efisiensi Boiler Menggunakan Metode Direct dan Indirect pada PLTU Jeneponto 2×135 MW
Authors: Habibuddin Musdholifah , Anshar Muhammad , Firman Firman
Published: September 2024

Salah satu mesin industri yang perannya sangat penting yaitu boiler. Boiler dalam perusahaan ini merupakan asset yang sangat penting bagi perusahaan, apabila terjadi masalah pada sistem boiler, maka kelancaran steam (uap) akan terganggu sehingga efisiensi boiler akan mengalami penurunan, oleh karena itu sangat diperlukan untuk mengkaji ulang kinerja mesin agar tidak terjadi pemborosan energi. Objek utama pada penelitian ini ialah Boiler PLTU Jeneponto 2 × 135 MW. Metode yang digunakan untuk menentukan efisiensi boiler yaitu metode langsung (Direct Method) dan metode tak langsung (Indirect Method). metode langsung (Direct Method) yaitu energi yang didapat dari fluida kerja (air dan steam) dibandingkan dengan energi yang terkandung dalam bahan bakar boiler, sedangkan metode tak langsung (Indirect Method) yaitu efisiensi merupakan perbedaan antara kehilangan panas (Heat loss) dan energi yang masuk. Penelitian ini bertujuan untuk mengetahui seberapa besar penurunan efisiensi boiler. Berdasarkan hasil penelitian dengan metode langsung (Direct Method) efisiensi boiler di tahun 2021 dan 2022 yaitu 42,63 % dan 64,11 % sedangkan dengan metode tak langsung (Indirect Method) efisiensi boiler sebelum dan sesudah overhaul yaitu 80,09 % dan 80,71 %.  Nilai kehilangan panas (Heat Losses) karena gas buang yang kering (Ldg) sebelum dan sesudah overhaul sebesar 6,40 % dan 5,87 %. Kehilangan panas karena penguapan air yang terbentuk oleh adanya H2 dalam bahan bakar (LH) sebesar 6,25 % dan 6,21 %. Kehilangan panas karena penguapan kadar air dalam bahan bakar (Lmf) sebesar 5,50 % dan 5,48 %. Kehilangan panas karena kadar air dalam udara (Lma) memiliki nilai yang sama yaitu 0,26 % , dan kehilangan panas karena radiasi dan kehilangan lain yang tak terhitung (Luc) sebesar 1,5 % .
Parametric optimization and comparative study of machine learning and deep learning algorithms for breast cancer diagnosis
Authors: Jain Parul , Aggarwal Shalini , Adam Sufiyan , Imam Mohsin
Published: September 2024

Breast Cancer is the leading form of cancer found in women and a major cause of increased mortality rates among them. However, manual diagnosis of the disease is time-consuming and often limited by the availability of screening systems. Thus, there is a pressing need for an automatic diagnosis system that can quickly detect cancer in its early stages. Data mining and machine learning techniques have emerged as valuable tools in developing such a system. In this study we investigated the performance of several machine learning models on the Wisconsin Breast Cancer (original) dataset with a particular emphasis on finding which models perform the best for breast cancer diagnosis. The study also explores the contrast between the proposed ANN methodology and conventional machine learning techniques. The comparison between the methods employed in the current study and those utilized in earlier research on the Wisconsin Breast Cancer dataset is also compared. The findings of this study are in line with those of previous studies which also highlighted the efficacy of SVM, Decision Tree, CART, ANN, and ELM ANN for breast cancer detection. Several classifiers achieved high accuracy, precision and F1 scores for benign and malignant tumours, respectively. It is also found that models with hyperparameter adjustment performed better than those without and boosting methods like as XGBoost, Adaboost, and Gradient Boost consistently performed well across benign and malignant tumours. The study emphasizes the significance of hyperparameter tuning and the efficacy of boosting algorithms in addressing the complexity and nonlinearity of data. Using the Wisconsin Breast Cancer (original) dataset, a detailed summary of the current status of research on breast cancer diagnosis is provided.
Tipping the Balance Between Cognitive Reserve, Frailty, and Dementia in the Very Old?
Authors: Ottaviani Silvia , Tagliafico Luca , Muzyka Mariya , Page Elena , Ottaviani Ennio , Ponzano Marta , Signori Alessio , Nencioni Alessio , Monacelli Fiammetta
Published: September 2024

Background: As the population ages, the concept of frailty becomes increasingly relevant and may be considered a precursor between aging and the development of dementia in later life. Similarly, the construct of cognitive reserve (CR) is an accepted model of cognitive resilience that may account for individual differences in trajectories of brain aging, mitigating the clinical expression of dementia. Objective: We aim to estimate the role of CR and frailty in moderating the prediction of dementia in the population aged over 80 who are attending an Italian outpatient memory clinic. Methods: Comprehensive Geriatric Assessment, Clinical Frailty Scale (CFS) to screen for frailty, and Cognitive Reserve Index questionnaire (CRIq) to evaluate CR, were used to assess patients systematically. We performed multivariate logistic regression to assess associations with dementia. Model performance and interaction between frailty and cognitive reserve were then evaluated. Results: 166 patients were consecutively enrolled (mean age was 85.7 years old, females composed 68%); 25% had a diagnosis of amnestic mild cognitive impairment, and 75% had a diagnosis of dementia. Multivariate regression analysis showed that CRIq and CFS were the main clinical assessment tools associated with the presence of dementia, even after collinearity adjustment. No significant interaction of CFS*CRIq was found. Conclusions: To our knowledge, this is the first study to investigate the association between CR, frailty, dementia, and their related interacting terms in a real-world population of very old patients. Our findings may suggest that both CR and frailty shape an individual’s resilience throughout their lifetime. This may potentially counteract the effects of brain neuropathology, in line with the hypothesis that meaningful associations exist between CR, frailty, and cognition in later life.
Emphasizing the Vital Role of Robust Peer Review: A Series of Publications Highlighting Potential Errors in Results Reporting and a Plea to Editors
Authors: Bornstein-Quevedo Leticia , Dueñas-Gonzalez Alfonso
Published: September 2024

PURPOSE: We present a series of publications on lung cancer in several well-recognized medical journals that present potential errors in the analyses and results of survival data. Our work stresses that a publication in a 'peer-reviewed journal' may not guarantee complete fact-checking or accuracy.

METHODS: We gathered publications on lung cancer on which we previously established communication with editors via formal letters to the editor and direct communications with them to comment on these works.

RESULTS: We present our analysis of survival results from seven publications in different journals. We found that these works did not meet the basic survival analysis principles. First, the progression-free survival (PFS) or overall survival (OS) percentages visually estimated from the curves do not match the number of events described in the figures or text at the median follow-up times of reporting. Secondly, death events are more common than progression events, resulting in higher PFS than OS curves. These two issues may severely jeopardize the authors' conclusions. Surprisingly, the journal editors communicated via formal letters or direct correspondence did not find mistakes or did not answer. Our work is beyond consideration as to whether these mistakes were deliberate or came from an honest error by the authors.

CONCLUSIONS: We state that journal editors should play a more active role in ensuring the accuracy of publications. Inaccurate data can significantly influence physicians' treatment decisions, potentially leading to ineffective treatments. This underscores the importance of our work and the need for improved accuracy in medical publications, as it directly impacts the professional practice of physicians.
Polarita v teorii mezinárodních vztahů
Authors: Kratochvíl Petr
Published: September 2024

Cílem stati je objasnit jak vývoj konceptu polarity, tak i jeho současné postavení a následně vytyčit směr, kterým by se výzkum v oblasti polarity měl ubírat, pokud budeme usilovat o zachování polarity jako teoreticky relevantní kategorie. Nejprve se stať věnuje definici polarity samotné i pojmů, kterés polaritou souvisejí (polarizace a koncentrace). Stať se dále zabývá vývojem chápání polarity ve druhé polovině 20. století se zvláštním zřetelem k Morgentahauovu a Kaplanovu pojetí, aby se následně přesunula k nejvýznamnějšímu tématu diskuze o polaritě, tj. k souvislosti mezi polaritou a systémovou stabilitou. Tato diskuze probíhala především mezi zastánci stabilní multipolarity (např. Deutsch a Singer) a jejich odpůrci, kteří naopak argumentovali ve prospěch stabilní bipolarity (např. Waltz). Tato neprůkazná diskuze vyústila v trojí reakci. Část vědců se pokusila o její řešení pomocí behavioralistické metodologie, druhá skupina badatelů usilovala o zpřesnění konceptu polarity a o jeho větší analytičnost a třetí proud polaritu zcela odmítl jako nástroj, který nemá dostatečnou vypovídací schopnost. Stať analyzuje i současný stav diskuze o polaritě. Velká pozornost se soustřeďuje na určení nedostatků polarity a návrhů na jejich řešení. K nejvýraznějším posunům patří rozdělení mocenské polarity na polaritu jednotlivých složek moci, které mj. umožní přesnější měření polarity. Další změnou je odpoutání polarity od neorealismu a větší příklon k historičtějšímu popisu reality a zaměření i na nestátní aktéry, popřípadě implikace plynoucí z výzkumu "nemateriálních" složek polarity.
Nacionalismus a komunismus ve světle vztahu mezi státem a menšinou na Balkáně
Authors: Tesař Filip
Published: September 2024

Autor ve své stati vychází z teze, že nacionalismus a komunismus se shodují v tom, že předkládají určitou správnou vizi společenské organizace, ve jménu jednoty (národní, lidové) připouštějí represi, součástí obou systémů je snaha očistit společenství od "nesprávných" prvků a oba rovněž předpokládají splnění nereálných cílů. Nacionalismus je tedy - jak uvedl Adam Michnik - možné v určitém smyslu považovat za poslední stadium komunismu. Přitom jde podle Gellnerovy definice o princip, který usiluje o uskutečnění shody mezi politickou a národní jednotkou. Autor si dále všímá konkrétní situace na Balkáně, a to jak z historického hlediska, tak i v současnosti. Rozlišuje přitom následující fáze: komunistické hnutí jako konkurenta nacionalistických hnutí, vítězství komunismu a zrovnoprávnění menšin, začlenění národní myšlenky do komunistické ideologie, nacionalismus jako integrální součást komunistické politiky. Situaci v Jugoslávii, respektive dnes v samostatných státech, srovnává se situací nejen v Rumunsku, v Bulharsku, ale též ve střední Evropě (tj. v Maďarsku, v Polsku, v České republice a na Slovensku).
Mezinárodní obchod s nebezpečným odpadem - volný trh versus environmentální regulace
Authors: Musil Michal
Published: September 2024

Jonathan Krueger: International Trade and the Basel Convention. Trade and Environment Series. 1st ed. London: The Royal Institute of International Affairs/Earthscan, 1999, 133 s., ISBN 1853836214.
Alois Holub a kol.: Metamorfóza světové ekonomiky na sklonku 20. století a její výhled
Authors: Hřích Jan
Published: September 2024

Alois Holub a kol.: Metamorfóza světové ekonomiky na sklonku 20. století a její výhled. 1. vydání. Praha: Oeconomica, 2002, 262 stran, ISBN 80-245-0318-2.
Detection of Avian Metapneumovirus Subtypes A and B in Moroccan Broiler Farms
Authors:   Laboratorios HIPRA S.A., Amer, Spain., Mernizi Amine , Kadiri Oumaima ,   Avian Pathology Unit, Department of Pathology and Veterinary Public Health, Agronomic and Veterinary Institute of Hassan II, Rabat, Morocco., Criado Rius Juan Luis ,   Laboratorios HIPRA S.A., Amer, Spain., Bouslikhane Mohammed ,   Microbiology, Immunology, and Infectious Diseases Unit, Department of Pathology and Veterinary Public Health, Agronomic and Veterinary Institute of Hassan II Rabat, Morocco., Ghram Abdeljelil ,   Epidemiology and Veterinary Microbiology Laboratory, Institute Pasteur of Tunis, Tunis, Tunisia., Mohamed Mouahid ,   Mouahid’s Private Vet Clinic, Temara, Morocco., Catelli Elena ,   Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy., Nassik Saâdia ,   Avian Pathology Unit, Department of Pathology and Veterinary Public Health, Agronomic and Veterinary Institute of Hassan II, Rabat, Morocco.
Published: September 2024

Background: Avian metapneumovirus (aMPV) is a widespread infectious respiratory pathogen affecting turkeys and chickens, with co-predominance of the subtypes A and B. Objectives: There is no official reports in Morocco about the subtypes of aMPV circulating. Hence, using quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) subtypes-specific A and B, we aimed at detecting and identifying the potential subtype(s) circulating. Methods: We conducted a longitudinal study on three broiler flocks that were strictly not vaccinated against aMPV and were located in two different geographical regions. We studied two flocks that expressed typical swollen head syndrome (SHS) and sampled them once. Furthermore, we sampled dead birds of one flock confirmed seropositive from a previous study. A total of 118 swabs pooled in 24 samples were subjected to RNA extraction and amplified using a triplex RT-PCR for specific detection of aMPV subtypes A and B. Additionally, serum samples were taken at slaughtering age to cross-check the molecular results. A total of 84 sera were analyzed with a commercial indirect enzyme-linked immunosorbent assay (ELISA) kit to detect and titer antibodies against the two subtypes. Results: Avian metapneumovirus was detected by qRT-PCR in all flocks. About 87.50% of the samples were positive for aMPV-B, and 16.67% for aMPV-A and aMPV-B simultaneously. All flocks showed seropositivity, confirming the molecular findings. Conclusion: The present investigation is the first molecular study in Morocco to elucidate the circulation of aMPV-A and aMPV-B in broiler farms in Morocco with a dominance of aMPV-B and the possibility of co-presence of both subtypes.
Omental Lipoma in a Slaughtered Lamb
Authors:   Department of Public Health, Faculty of Health, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran., Mahaki Mohammad Ebrahim , Chaleshtori Sirous Sadeghian ,   Department of Internal Medicine, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran, Azarabad Hasti ,   Department of Pathology, Hamidreza Fattahian Pet Hospital, Tehran, Iran., Shokri Arman ,   Department of Internal Medicine, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
Published: September 2024

Lipoma is a benign tumor of well-differentiated adipocytes that has been reported in some domestic animals. Omental lipomas in human and domestic animals are rare and reported as a case report. This study aimed to report an omental lipoma in a slaughtered sheep. In the observational examination of a sheep in a slaughterhouse in Tehran Province, Iran, and during the inspection of the abdominal area, a mass was seen on the greater omentum. The mass was sampled and placed in 10% formalin for histopathology. The mass was single, soft, dense, capsuled, oval, weighing 150 g, and 4.5×3.5 cm in size. Microscopic examination showed omental mass composed of uniform and mature lipocytes encased within a thick layer of immature connective tissue. The final diagnosis was primary benign lipoma. Lipoma can occur anywhere in the body where there are fat cells, and probably obesity and trauma are important risk factors for its occurrence. The size of the lipoma mass may help predict the age of the mass.
A Histopathological Study on the Changes in the Central Nervous System of Dead Cats With Neurological Symptoms
Authors:   Department of Veterinay Pathology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran., Ramezanpour Eshkevari Shahb , Sasani Farhang ,   Department of Veterinay Pathology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran., Shokrpoor Sara ,   Department of Veterinay Pathology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran., Mardjanmehr Seyed Hossein ,   Department of Veterinay Pathology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran., Akbarein Hesameddin ,   Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran., Ashrafi Iradj ,   Department of Microbiology and Immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
Published: September 2024

Background: Neurological conditions constitute approximately 10% of feline cases referred to veterinary clinics. Such cases often present manifestations of central nervous system (CNS) damage, including inflammatory lesions, neoplastic growth and structural and cellular transformations. Objectives: This study aimed at identifying histopathological changes in the CNS of cats that had succumbed to neurological symptoms. Methods: Microscopic evaluation of different sections within the CNS was conducted on 20 cats that had either died naturally or were euthanized due to neurological signs. After performing a necropsy, we examined the CNS tissues and conducted PCR testing to screen for possible viral infections, including feline infectious peritonitis (FIP), feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). Results: The majority of cases showed characteristic histopathologic lesions, notably mononuclear and suppurative meningoencephalitis, perivascular cuffing, disseminated intravascular coagulation (DIC), granulomatous meningoencephalitis, acute neuronal necrosis, liquefactive necrosis, epididymitis, thrombosis and demyelination. Among the 20 cats studied, 12 tested positive for FIP by PCR analysis, while 5 cats exhibited positive results for FIV. Also, FeLV PCR tests displayed positive results in 4 cats. No evidence of feline spongiform encephalopathy (FSE) was observed. Conclusion: This study is the first of its kind conducted in Iran. Based on the results, the most prevalent viral agents infecting cats’ CNS were FIP, FIV and FeLV. The investigation revealed no evidence of FSE in cats with neurological signs.