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ABSTRACT How is it that the millions of visitors who flock to science centers each year are able to make use of the exhibits there? How do they discover the properties of previously unknown machines? How much time does it take? What is the significance of the process? An issue of particular interest to us is how visitors figure out what they can do with an exhibit and how they can do it. We interpret this as a process of instrumentalization, transforming an object into an instrument of human activity. Drawing on the Instrumented Activity Situations Model, this paper focuses on the instrumentalization of exhibits and the sense‐making process within the visitor–exhibit physical interaction. After discussing two empirical cases of children (9 and 11 years old) interacting with an open‐ended dynamical exhibit, we claim that by instrumenting an exhibit under a set of inherent constraints, visitors develop new enactive competence (coordinated motor action tethered to new perceptual orientation), just as one would learn to ride a bicycle or to work with a lathe machine. We argue that the attention of researchers, hitherto focused primarily on content‐based knowledge development, should be equally focused on the kind of procedural knowledge development evident in “making a machine one's own.” [ABSTRACT FROM AUTHOR]

In 2009, during research of a cemetery of the Wielbark culture in Czarnówko (Lębork District, Pomerania), an inhumation grave was discovered, which contained the remains of a wooden bowl with copper alloy fittings. Inside it, several hazelnuts were preserved. This vessel, in the light of the analysis carried out, was made of alder wood using a turning technique. Discoveries of this type are not only rare in the area of the Wielbark culture, but also in the rest of Central European Barbaricum. This article presents the results of the archaeobotanical research and demonstrates the bowl in the broader context of Roman Period discoveries. [ABSTRACT FROM AUTHOR]

Wood is a sustainable, benign, and high-performing green structural material readily available in nature that can be used to replace structural materials. However, insufficient mechanical performance (compared to metals and plastic), moisture sensitivity, and susceptibility to microorganism attack make it challenging to use wood as it is for advanced engineering applications. We here present an efficient approach to fabricating densified wood with minimal time and waste generation, demonstrating high mechanical strength, and decreased water penetration on the surface. Wood slabs were treated with deep eutectic solvents (DESs) to solubilize the lignin, followed by in-situ regeneration of dissolved lignin in the wood. Then, the slabs were densified with heat and pressure, turning the wood into a functionalized densified material. Lignin regeneration and morphological changes were observed via two-photon microscopy and Scanning Electron Microscopy (SEM), respectively. The final product is less susceptible to water absorption on the surface and has enhanced flexural strength (> 50% higher), surface hardness (100% increased), and minimal set recovery compared to natural wood. The improved mechanical performance is due to regenerated lignin which acts as a glue and fills spaces present within the interconnected cellulose network inside the wood, forming a highly dense composite during densification. Such enhancement in the properties of DES-densified wood composite makes it a favorable candidate for advanced structural and engineering applications. [ABSTRACT FROM AUTHOR]

This paper delves into a critical aspect of Computer-Aided Production Planning (CAPP): the automated detection of the main rotational axis in turning parts within Computer-Aided Designs (CAD). The identification of the principal turning axis in CAD models presents numerous opportunities in the field of CAPP. In this study, the authors employ advanced surface segmentation techniques to analyse the surface geometry, pinpointing rotational surfaces within the CAD model. Subsequently, significant features are extracted from these identified rotational surfaces, and the necessary data for rotational centers are gathered. By fine-tuning the weighting of the data gathered, the approach can be tailored to suit various planning strategies. This approach has the potential to significantly enhance both the efficiency and accuracy of the automated production planning process for turning parts in CAPP. [ABSTRACT FROM AUTHOR]

Dyes are frequently used in industries such as textile, leather, paper and printing, to water sources causes harmful effects on the environment and human health. Therefore, it is crucial to effectively remove colored contaminants from water in order to protect the environment and public health, maintain biodiversity and preserve the esthetic aspects of water resources. In this study, wood chips obtained from Pinus brutia (PB) tree grown in many parts of the world were turned into biochar and then modified and used for the removal of malachite green, a cationic dye. For this purpose, biochar (PBB) was made by collecting PB wood and turning it into chips (PB). Later, PBB was modified to gain nano-magnetic properties. The structure of the obtained PBB and nM-PBB adsorbents was characterized by FT-IR. pH (2–9), temperature (25 °C–55 °C), time change (15 min-240 min), adsorbent amount change (0.05 g–0.45g) and MG concentration (25 mg/L–250 mg/L) were investigated in MG removal of PBB and nM-PBB. The process was found to be pseudo-second-order and spontaneous endothermic reaction. PBB and nM-PBB were found to be suitable for Langmuir isotherm in MG removal (qmax=13.004 mg/g for PBB, qmax=18.215 mg/g for nM-PBB). Various adsorbents are used to remove different substances from water. The use of pinus brutia tree, which is a biochar product, in the removal of malachite green dyes from aqueous solutions has not been found in the literature. The findings revealed that Pinus brutia could be used to extract malachite green, a cationic dyestuff. Pinus brutia is a widely distributed, easy-to-access, low-cost species with many uses. Our study, in which Pinus brutian is used as an adsorbent, will contribute to the literature in this respect, and its use in the removal of different anionic and cationic dyes will be discussed in the future. [ABSTRACT FROM AUTHOR]

In this paper, the influence of ultrasonic vibration on the forming forces and surface quality of products formed using an ultrasonic-assisted incremental sheet forming (UISF) method was investigated and compared with an incremental sheet forming (ISF) method. The elements and parameters used for research include a sheet of Al 5052 aluminum alloy with thickness of 1.0 mm, a lathe with a feed rate of 70-130-225 rpm, and step size of 1.0-1.5-2.0 mm. The results show that ultrasonic vibration significantly reduces the forming forces, of which the main forming force Fzmax is reduced by about 20%. Besides, the results also show that the surface quality of products formed via UISF is significantly improved compared to that formed by ISF. [ABSTRACT FROM AUTHOR]

Line-shaped beam-based Doppler distance sensors enable 3D shape measurements of rotating objects, for instance for working lathe monitoring with a simultaneous, multipoint velocity, and distance measurement. The velocity and distance estimations are fundamentally referred to the interference fringe spacing of the sensors. In this case, the fringe spacing variation-caused measurement error is significant; however, a complete, accurate model of the fringe geometry distribution for the line-shaped fringe volume is still missing and required to identify and minimize the error. Therefore, this work presents a high-accuracy 3D model for the fringe spacing evaluation of the sensors with experimental investigations. The model is derived from the phase expression of Gaussian beams introducing extension ratio, and can be universally applied to describe fringe geometry distribution throughout the intersection volume of spherical and line-shaped beams. With an experimental setup of a laser Doppler sensor, a full-field fringe spacing estimation using a high-resolution matrix camera is performed with dual-wavelength beams. The numerical modeling and experimental results show an average relative difference below 0.6 % . [ABSTRACT FROM AUTHOR]

In the engineering world, the machining of advanced materials like titanium alloys, which is having their superior applications in a variety of domains, that is, bio-implants, biomedical, aerospace, and so on, has been a challenge for many decades to the researchers. The optimised surface topography for such alloys has been revealed as a function of various input parameters. In this study, an attempt has been made by conducting the experimental investigation on the surface integrity and the quality machined work surface in turning of titanium alloy, that is, Ti6Al4V through employing cryogenically treated and non-cryogenically processed CBN inserts. The surface quality and the integrity of processed titanium alloy work-surface have been investigated under the influence of various considered input factors. The design of experimentation was constructed for planning the experiments. The analysis of variance test has been attempted for the studied response, that is, surface roughness and the mathematical models for the studied surface roughness (with both CBN inserts; cryogenically and non-cryogenically treated) have also been developed. The attained optimised parametric conditions for surface roughness are; feed rate – 0.067 mm/rev, cutting speed – 63.852 m/min, and depth of cut – 0.526 mm; and feed rate – 0.066 mm/rev, cutting speed – 59.450 m/min, and depth of cut – 0.309 mm, for non-cryogenically and cryogenically treated CBN inserts, respectively. Artificial neural network (ANN)-based modelling has also been attempted to predict and analyse the dataset of experiments. There is a variation of 1.43% between ANN predicted data of NC CBN and NC CBN experimental data. Further, there is an error of 0.2% between ANN predicted data of Cryo-CBN and Cryo-CBN experimental data. The microstructure analysis of the turned titanium surface reflected the presence of few tearing and groove lines with both the CBN inserts employed. The scratches and bamboo lines have been due to the built-up edges produced in the inserts. [ABSTRACT FROM AUTHOR]

By exploring the career of the German forester Johann Albrecht v. Monroy from the 1920s to the 1950s, this article seeks to further differentiate and expand the historiography on development. It reveals that experts like Monroy who were deeply involved in the National Socialist quest for hegemony in Europe took an active part in shaping the Food and Agriculture Organization's (FAO) forest-related development activities after the Second World War. The article provides two explanations why Monroy became a lauded development pioneer: Firstly, he was a widely acknowledged and well-connected member of a transatlantic expert community that he had helped to shape in the 1920s and 1930s. Secondly, he enormously benefitted from German expansionist policies. In the 1930s, Monroy became a senior official responsible for turning forestry and wood processing industries into a central branch of Germany's war economy. During the war, he was in charge to establish the most modern wood processing plant in Slovakia. Monroy based this project on a specific approach to development that he had elaborated since the mid-1930s and that adapted schemes shaped for colonial contexts to the very special international environment of German-controlled Europe. That Monroy could realize this project in Slovakia turned him into an expert wanted by the FAO due to an almost unrivalled experience. [ABSTRACT FROM AUTHOR]

The purpose of the research in this paper is to investigate the impact of cutting conditions on the load on servo motors at a three-axis computer numerically controlled (CNC) Hitachi Seiki Seicos lathe. The analyzed parameters (cutting speed, feed, and depth of cut) play a crucial role in the turning process. It is significant that each cutting condition directly alters the value of the load on the power system and has a significant effect on cutting forces, which in turn affect the load on the servo motors at the CNC lathe during the process. [ABSTRACT FROM AUTHOR]

Cutting force in lathe work is closely related to tool wear and affects the turning quality. Direct measurement of the cutting force by measuring the strain of the tool holder is challenging because the tool holder design aims to be highly rigid in order to undertake large cutting forces. Accordingly, the most popular dynamometer designs modify the standard tool holder by decreasing the structural rigidity of the holder, which reduces the machining precision and is not widely accepted. In order to solve the issue of the low stiffness of the dynamometer reducing the machining precision, in this paper, the ultra-low strain on the tool holder was successfully detected by the highly sensitive semiconductor strain gauges (SCSG) adjacent to the blade cutting insert. However, the cutting process would generate much heat, which increases the force measuring area temperature of the tool holder by about 30 °C. As a result, the readout drifted significantly with the temperature changes due to the high temperature coefficient of SCSG. To solve this problem, the temperature on the tool holder was monitored and a BP neural network was proposed to compensate for temperature drift errors. Our methods improved the sensitivity (1.14 × 10−2 mV/N) and the average relative error of the BP neural network prediction (≤1.48%) while maintaining the original stiffness of the tool holder. The smart tool holder developed possesses high natural frequency (≥6 kHz), it is very suitable for dynamic cutting-force measurement. The cutting experiment data in the lathe work show comparable performance with the traditional dynamometers and the resolution of the smart tool holder is 2 N (0.25% of total range). [ABSTRACT FROM AUTHOR]

In 1920, Casey Albert Wood (1856–1942), a prominent Canadian ophthalmologist and bibliophile, began what was essentially a second career as an amateur ornithologist and author. This paper examines the path Wood followed as he learned more about birds and developed a network of colleagues that aided his transition to a respected member of the American Ornithologists' Union (AOU) and prolific author on ornithology. It also seeks to place Wood's ornithological writings within the contemporary scientific and popular literature on birds. After his retirement from medical practice in 1920, Wood and his wife Emma (née Shearer) (1859–1951) travelled extensively and Wood's ornithological observations were published in journals varying from scientific publications like the AOU's The Auk and the Cooper Ornithological Society's The Condor, to more popular magazines like the Audubon Society of the Pacific's The Gull. Wood's contributions often combined natural history observation with literary allusions and personal reminiscence. Towards the end of his second career, Wood turned to his bibliophile interests, publishing a catalogue of the McGill Library holdings in vertebrate zoology as well as a translation co-authored with his niece Florence Marjorie Fyfe (1892–1965) of Frederick II of Hohenstaufen's De arte venandi cum avibus. Wood was representative of an earlier generation of gentlemen ornithologists, eulogized in his obituary in The Auk as "probably the most broadly cultured and deeply learned of his generation in our Union". [ABSTRACT FROM AUTHOR]

Numerous training simulators have been developed using virtual reality (VR) owing to their various advantages. Systems for training machine operations with physical movements face differences in the operational feel between actual and virtual machines. Moreover, virtual training is problematic in safety education because trainees in safe virtual environments can exhibit unsafe behavior in reality. To solve these problems, a previous study developed a virtual reality (VR) system to train a lathe operation with mixed reality using a motion capture system. This study included a function to teach the procedure and safety precautions for straight turning operations using a lathe. To evaluate the training effectiveness of this system, an experiment was conducted to compare learning using a video. Testees were divided into a simulator group, who learned with the system, and a video group, who learned with the video material. Work on the actual lathe by each testee after learning, was evaluated. Consequently, the actual work by the testees who used this system had fewer errors and shorter standstill times in which they attempted to recollect the next phase task. Although the number of trainees was small, this relationship had a statistical advantage. In the actual work, all the testees in the video group entered the danger area; however, only half of the testees in the simulator group entered the danger area. Therefore, a trainee using a simulator can remember the work process more reliably and accurately and perform it safely. Moreover, trainees who have undergone training several times should be able to perform actual work without making operational errors or engaging in unsafe behaviors. [ABSTRACT FROM AUTHOR]