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In the manufacturing industries, noise is one of the most common health hazards at workplaces. In wood machining, for instance, circular sawing processes in particular produce high noise emissions that often exceed the permitted limits. The main source of noise is the rotating circular saw blade, whose aeroacoustic behavior is influenced by air turbulence on the tool contour. So far, no numerical approach to study and optimize the aeroacoustic noise emissions from circular saw blades has been investigated. This paper addresses this deficit and presents a methodology for modeling the flow-induced sound generation on rotating circular saw blades based on computational fluid dynamics (CFD) simulations. With the implementation of the acoustic analogy according to Ffowcs-Williams/Hawkings, the sound pressure levels could be calculated with sufficient accuracy. With deviations between 7 and 10%, the influence of the rotational speeds could be plausibly modeled. Based on the validated numerical model, geometry variants with various modifications were investigated regarding their potential for reducing sound pressure levels. Based on a conventional reference geometry, different chip space volumes and various modifications to the tooth rim and tooth shape were investigated and evaluated as part of simulative parameter studies. Sound pressure level reductions in the range of 2.2–10.8 dB were achieved. The results obtained and the systematic approach investigated provide a suitable set of instruments for industrial practice. Digital prototypes can be designed at an early stage in the product development phase of circular saw blades regarding their aeroacoustic properties. [ABSTRACT FROM AUTHOR]

Stubble cutting is a critical step in the mechanized harvesting of mulberry trees. Poor stubble cutting quality can lead to root decay, and even the death of the trees, reducing the rate of rejuvenation. In view of the relatively high damage rate of stubble cutting in the mulberry harvesting operations, this paper has conducted in-depth research and designed a mulberry branch harvesting and stubble cutting test machine. The overall structure and key technical parameters of the machine were determined and the design of critical components was theoretically analyzed. Field tests identified an optimized set of cutting parameters that effectively reduced stubble damage and energy consumption. The optimal parameter combination included a saw blade line speed of 74 m/s, a star-wheel ground clearance of 727 mm, and a cutting speed ratio of 93, resulting in a cutting energy consumption within 1 m of 241 mJ and a stubble score of 8.5. These parameters met the quality standards for mulberry harvesting. This research provides valuable data support for analyzing and optimizing the cutting parameters of mulberry stubble-cutting machines, laying a solid foundation for advancing mechanized harvesting technology for mulberry trees. [ABSTRACT FROM AUTHOR]

In order to enhance the efficiency of stone sculpture machining while reducing natural stone waste and environmental pollution, a method for the efficient and green sawing of natural stone sculptures using industrial robots is proposed. The model contour is used as the directrix of the ruled surface to construct a ruled surface model that minimizes volume. The contour curve corresponding to this minimized-volume ruled surface model serves as the machining path for an integrated robotic diamond wire cutting system. A ruled surface model of Stanford Bunny was obtained by sawing a marble block using the robotic diamond wire cutting system. The experimental results show that the material removal rate of the robotic diamond wire cutting is 1.37 times that of saw blade cutting and 2.30 times that of grinding. The volume of stone powder generated during the processing was 0.16×10⁷mm³, accounting for only 1.47% of the total stone powder produced during the grinding process. In summary, the proposed method not only enhances processing efficiency but also reduces natural stone waste and mitigates environmental pollution. [ABSTRACT FROM AUTHOR]

Circular saw blades, a large diameter-to-thickness ratio tool, are widely used in the aerospace and transportation sectors. However, it is limited due to its thinning tendency and weak stiffness. In this study, a novel tool tensioning technique was developed using the ultrasonic surface rolling process (USRP) to improve the tool performance of circular saw blades by changing the microstructure and residual stress distribution. Archimedean spiral curve textures were successfully created on both sides of a circular saw blade using an ultrasonic rolling experimental platform. The results show that USRP induced a gradual change in the dislocation structure from a microstrip mixing pattern to a lamellar band structure, accompanied by an increase in high-angle boundaries and a decrease in dislocation cell size. These textures result in a "low–high-low" trend in the radial residual stress distribution along the radius of the circular saw blade, and this residual stress variation improves the tool dynamic performance of the circular saw blade by more than 10% based on real-time x-direction (feed direction) cutting vibrations. In addition, a rolling tensioning evolution mechanism is proposed to explain how the synergistic effect of ultrasonic vibration and rolling force generates the residual stress field. This study elucidates the evolutionary mechanism of USRP-induced tensioning of thin circular saw blades, paving the way for a high-quality, cost-effective tensioning process. [ABSTRACT FROM AUTHOR]

The benefits of a new woodworking system are considered. Ongoing adjustment of sawblade tension is possible in the new system. A self-locking device for raising the upper shaft of the saw assembly also ensures tension of the saw blades in six modules. The parameters of the electrical micromotors and the reliability of the mechanisms ensuring blade tension are determined. [ABSTRACT FROM AUTHOR]

High energy consumption and poor processing quality are common problems in wood sawing. To address these issues, in this article, specific cutting energy and surface roughness were investigated with saw blade speed as control variables. Analysing the effect of parameters on specific cutting energy and surface roughness. The sawing parameters were optimised with the objectives of minimum specific cutting energy and minimum surface roughness. The findings indicate that specific cutting energy and surface roughness reduction with increasing rake angle; specific cutting energy and surface roughness decrease with increasing spindle speed; specific cutting energy decreases and surface roughness increases with increasing feed rate. ANOVA analysis reveals that sawing speed (n) has the most significant impact on specific cutting energy during oak cutting. The optimal solution derived from TOPSIS suggests a specific cutting energy of 2E7 J/m3 and a surface roughness of 1.758 μm. The innovation of this paper is the study of the specific cutting energy and the optimisation of parameters. These findings provide valuable theoretical and practical guidance for enhancing the efficiency and quality of oak processing while minimizing energy consumption. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cemented carbide circular saw blades are widely used for wood cutting, but they often suffer from vibration and noise issues. This study presents a multi-objective optimization method that integrates ANSYS and MATLAB to optimize the design of noise reduction slots in circular saw blades. A mathematical model was developed to correlate the emitted sound power with the overall vibration intensity. A multi-objective optimization model was then formulated to map the slot shape parameters to the deformation, equivalent stress, and vibration intensity during sawing. The ABAQUS thermal–mechanical coupling analysis was used to determine the sawing force and temperature field. The NSGA-II algorithm was applied on the ANSYS–MATLAB platform to iteratively compute slot shape parameters and conduct optimization searches for a globally optimal solution. Circular saw blades were fabricated based on the optimization results, and experimental results showed a significant reduction in sawing noise by 2.4 dB to 3.0 dB on average. The noise reduction effect within the specified frequency range closely agreed with the simulation results, validating the method's efficiency. This study provides a feasible and cost-effective solution to the multi-objective optimization design problem of noise reduction slots for circular saw blades. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental investigation of the influence of electrode configuration on corona discharge and particle collection under ambient climatic conditions in Blade-to-Plane Electrostatic Precipitator (BP-ESP). In an experimental-scale electrostatic precipitator (BP-ESP), electrodes of different shapes (blade, saw blade with small tooth, and saw blade with large tooth) were tested. The experiments were performed with three types of dust particles having a mean size of about 5 µm, 10 µm, and 45 µm. An aerosol spectrometer was used to characterize the chemical composition of these dust particles injected into the ESP. Different DC-applied voltages have been taken into account for both positive and negative polarities. Results showed that a high current was generated with a saw blade electrode with large teeth which increased the particle collection efficiency, for both polarities. The negative corona discharge is overall more effective than the positive one for the different configurations of electrodes and dust particles used. [ABSTRACT FROM AUTHOR]

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Leaf and scape anatomy of Allium glandulosum Link & Otto, Allium kunthii G. Don, Allium scaposum Benth., and Allium durangoense Traub were studied comparatively for the first time. The aim was to analyze and provide characters with a possible taxonomic value. The samples collected in the field were processed using a conventional paraffin-embedding technique. Some characteristics of foliar anatomical characters of Amerallium Traub were confirmed. The shape of the blade seen in cross-section presents an obovate depressed shape, except in A. glandulosum, which was obtriangular. Anatomical characteristics of the leaf and scape, such as the prominent cells of the epidermis, the thickening of cells adjacent to the vascular bundles, and the type of cuticle, allow the four species to be differentiated. The presence of papillose cuticle and prominent cells, as well as stomatal occlusive cells with anterior extensions, is reported for the first time for the genus. Leaf and scape anatomy supports the recognition of the four species analyzed. [ABSTRACT FROM AUTHOR]

Copyright of Diamond & Abrasives Engineering is the property of Zhengzhou Research Institute for Abrasives & Grinding and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vibroacoustic metamaterials represent an innovative technology developed for broadband vibration reduction. They consist of an array of local resonators and are able to reduce vibrations over a wide frequency range, commonly referred to as a stop band. Vibroacoustic metamaterials may be a promising strategy to reduce out-of-plane vibrations of thin-walled, disk-shaped structures, such as saw blades. However, their behavior in rotating systems has not yet been fully understood. In this study, a vibroacoustic metamaterial integrated into a circular disk for the reduction of out-of-plane vibrations is experimentally investigated in the rotating and non-rotating state. Derived from the predominant frequency range of noise emitted by saw blades, a vibroacoustic metamaterial with a numerically predicted stop band in the frequency range from 2000 Hz to 3000 Hz, suitable for integration into a circular disk, is designed. The resonators of the metamaterial are realized by cutting slots into the disk using a waterjet cutting machine. To experimentally examine the structural dynamic behavior, the disk is excited by an impulse hammer and observed by a stationary optical velocity sensor on a rotor dynamics test stand. The results of the rotating and the non-rotating state are compared. The measurements are carried out at two different radii and at speeds up to 3000 rpm. A distinct stop band characteristic is shown in the desired frequency range from 2000 Hz to 3000 Hz in the rotating and non-rotating state. No significant shift of the stop band frequency range was observed during rotation. However, adjacent modes were observed to propagate into the stop band frequency range. This work contributes to a better understanding of the behavior of vibroacoustic metamaterials in the rotating state and enables future applications of vibroacoustic metamaterials for vibration reduction in rotating, disk-shaped structures such as saw blades, brake disks or gears. [ABSTRACT FROM AUTHOR]

A multi-objective optimization design method based on the MATLAB/ANSYS co-simulation non- dominated aorting genetic algorithm II (NSGA-II) was proposed and implemented in this paper. The method was used to complete the design of silencing slits for ultra-thin circular saw blades. Topology optimization was performed in Inspire software by using the variable density method to determine the design domain of the silencing slit. The location, angle, and width of the silencing slit were taken as the design variables. Maximum deformation, maximum equivalent force, and overall amplitude were taken as the design objectives. On this basis, a multi-objective optimization model was established. The optimized solution of the model was carried out by the strategy of MATLAB/ANSYS co-simulation in collaboration with NSGA-II. The results showed that all the four optimized solutions can effectively reduce the deformation and overall amplitude of the saw blade during sawing, which provided a wider range of choices for decision makers. The study provided a possible solution to the problem of multi-objective optimal design of silencing slits for circular saw blade. [ABSTRACT FROM AUTHOR]

In order to explore the influence of textured sawteeth on saw blade cutting and wear performance, linear micro textures perpendicular to the chip flow direction were fabricated on the rake face, main flank face, and secondary flank face by laser machining, respectively. The cutting tests were carried out on sawing platform with different cutting speeds under lubrication conditions. The cutting forces, noise, temperatures, machined surface quality, and sawtooth wear were investigated. The results indicated that textures fabricated on the secondary flank face can effectively reduce friction with the machined surface and improve the surface quality, and the roughness Ra decreased about 2.5 ~ 12.5% compared with traditional saw blade. The improvement of saw blade cutting performance by machining micro textures on the main flank face was greater than the textures fabricated on the rake face. Due to the synergistic action of textures on different cutting faces, the cutting force, noise, and temperature of saw blades with textures prepared on all cutting surfaces were the lowest. The main wear forms of sawteeth were tip wear, surface adhesion wear, and oxidation wear. Although the derivative cutting phenomenon occurred, the micro textures were not completely filled, which signified that the micro textures still played the role of stored cutting fluids, reduced contact area, and formed lubrication film. [ABSTRACT FROM AUTHOR]

In order to enhance the quality of diamond composite materials, this work employs a Cu-Co-Fe and Ni-Cr-Cu pre-alloyed powder mixture as a transition layer, and utilizes laser-welding technology for saw blade fabrication. By adjusting the laser-welding process parameters, including welding speed and welding power, well-formed welded joints were achieved, and the microstructure and mechanical properties of the welded joints were investigated. The results demonstrate that the best welding performance was achieved at a laser power of 1600 W and a welding speed of 1400 mm/min, with a remarkable tooth engagement strength of up to 819 MPa. The fusion zone can be divided into rich Cu phase and rich Fe phase regions, characterized by coarse grains without apparent preferred orientation. The microstructure of the heat-affected zone primarily consists of high-hardness brittle quenched needle-like martensite, exhibiting a sharp increase in microhardness up to 550 HV. Fracture occurred at the boundary between the fusion zone and the heat-affected zone of the base material, where stress concentration was observed. By adjusting the welding parameters and transition layer materials, the mechanical properties of the joints were improved, thereby achieving a reliable connection between diamond composite materials and the metal substrate. [ABSTRACT FROM AUTHOR]

Bone loss from the kerf of the sawblade may influence the final outcomes when employing three-dimensional-printed surgical guides. However, no studies have systematically addressed saw blade-induced bone loss. This study aims to quantify bone loss and propose a reduction guide to minimize the fracture gap. The postoperative gap tended to decrease as the amount of gap compensation increased. Osteotomy gaps can be attributed to the thickness of the saw blade, and the proposed methodology addresses this surgical error. Surgeons can proactively plan and design reduction guides with applied compensation using the method described in this study. [ABSTRACT FROM AUTHOR]

This study is an attempt for comprehensive, combining experimental data with advanced analytical techniques and machine learning for a thorough understanding of the factors influencing the wear and cutting performance of multi-blade diamond disc cutters on granite blocks. A series of sawing experiments were performed to evaluate the wear and cutting performance of multi blade diamond disc cutters with varying diameters in the processing of large-sized granite blocks. The multi-layer diamond segments comprising the Iron (Fe) based metal matrix were brazed on the sawing blades. The segment's wear was studied through micrographs and data obtained from the Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray (EDS). Granite rock samples of nine varieties were tested in the laboratory to determine the quantitative rock parameters. The contribution of individual rock parameters and their combined effects on wear and cutting performance of multi blade saw were correlated using statistical machine learning methods. Moreover, predictive models were developed to estimate the wear and cutting rate based on the most significant rock properties. The point load strength index, uniaxial compressive strength, and deformability, Cerchar abrasivity index, and Cerchar hardness index were found to be the significant variables affecting the sawing performance. [ABSTRACT FROM AUTHOR]

Cemented carbide saw blades offer significant advantages like high cutting efficiency and good cutting performance in the processing of metal materials, especially hard-to-cut alloy materials. The appropriate interface state between carbide and metal matrix is a critical factor for achieving its machining performance. In this study, the joint of WC-Co10 and B318 steel was numerically investigated for various temperatures and thermal cycle parameters in terms of the joint's stress and strain. The elastic-plastic properties of materials with temperature were followed to conduct simulations. The minimum temperature caused a plastic strain in the joint was determined. Additionally, effects of the temperature parameters on the stress distribution shape and plastic zone along the interface were presented by equivalent stress/strain in detail. As a result of the study, it was determined that obvious stress concentration appeared in the vicinity of the WC-Co/steel interface under temperature, and when the temperature reaches 176 °C, plastic behavior took place at both ends of the joint. The plastic region extended towards the interface center with increasing temperature. During the thermal cycling, the thermal ratcheting of plastic strain occurred at points of the joint, and it was also determined that there was a moderate correlation between ratcheting shakedown state and times of thermal cycles, although the cycle temperature ranges were different. [ABSTRACT FROM AUTHOR]

This study examines the possible utilization of machine learning and decision-making in the woodworking sector. This refers to the recognition of certain sounds produced during tool idling. The physical and geometric properties of the circular saw blade result in different noises being generated during idling. It was assumed that the respective circular saw blades can be recognized by these noises. The noises of three different circular saw blades were examined while idling at the same speed. In order to obtain useful data for the deep learning process, the coarse signals were subjected to frequency analysis. A total of 240 noise samples were taken for each circular saw blade and later subjected to signal processing. Frequency-power spectra were created using a custom program in Matlab Campus Edition software, such as for the spectrograms. A short Fourier transform was used to create the average spectral density plot using self-made software. The input data for the deep learning network was created in Matlab using a custom program. The GoogleNet deep learning network was used as a data classifier. After training the network, an accuracy of 97.5% was achieved in recognizing circular saw blades. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To determine the effects of using either a linear or curvilinear oscillating, battery-powered saw blade on the extent of bone resection, bone fissure or fragmentation, soft tissue trauma, and surgical time for femoral head and neck excision (FHNE) in feline cadavers. ANIMALS: 18 feline cadavers. METHODS: Paired feline cadaveric femora were randomly assigned to either a 10 mm linear or 12 mm curvilinear blade for FHNE by 2 surgical residents. CT of each femur pre- and postoperatively were used to create 3D reconstructions of each femur. The residual remaining or excessively resected bone volume at the ostectomy site was compared to an "ideal" ostectomy line made by a board-certified surgeon on preoperative CTs. RESULTS: There were no significant differences in residual or excessive bone resection by a saw blade (P = .84), between surgeons (P = .65), or in surgery time (P = .39). When compared to the "ideal" ostectomy, the linear saw blade removed slightly less bone compared to the curvilinear blade, but was not statistically significant (P = .82). No fissures or fractures were noted; however, the curvilinear blade removed the entire lesser trochanter in 1 cadaver and the linear blade partially removed the greater trochanter in 1 femur and 2 lesser trochanters in 2 femora. CLINICAL RELEVANCE: The use of a curvilinear blade may be a viable option for performing FHNE in cats. In vivo studies are warranted to determine its efficacy in clinical cases where FHNE is performed and the incidence of complications postoperatively. [ABSTRACT FROM AUTHOR]

The combined rock breaking method with the saw blade and conical pick is proposed to improve the rock breaking efficiency. The numerical simulation of combined rock breaking with the saw blade and conical pick is established to investigate the rock damage mechanism. And verified and modified the numerical simulation model with the rock breaking comprehensive test bench, the quantitative analysis error is less than 0.05, indicated quantitative analysis system is accuracy. The result indicated that the cutting parameters of the saw blade and conical pick affect the rock damage. And the cutting parameters of conical pick and structural parameters of rock plate have been studied to influence rock breaking volume. The research result could help optimize the cutting parameters of the saw blade and conical pick to improve the rock breaking efficiency. [ABSTRACT FROM AUTHOR]

The presented work focuses on the experimental investigation of a vibroacoustic metamaterial integrated into a spinning circular saw blade. Vibroacoustic metamaterials are a novel technology for broadband vibration reduction. Built from an array of local resonators, a broadband vibration reduction characteristic in the frequency domain (a so-called stop band) can be achieved. A design of a vibroacoustic metamaterial suitable for integration into a circular saw blade is developed and a numerical stop band prediction is performed. The resonators of the vibroacoustic metamaterial are integrated into the saw blade with a water jet cutting machine to create slots, forming flaps that are free to oscillate. The structural dynamic behavior of the saw blade with integrated vibroacoustic metamaterial is experimentally investigated on a rotor dynamic test bench and compared to that of a standard saw blade. The saw blades are excited by an automatic impulse hammer and the resulting out-of-plane vibrations are measured with a laser vibrometer at two different radii. Measurements are conducted at different rotational speeds up to 1800 rpm. Up to rotational speeds of 1000 rpm a stop band characteristic in the frequency range of 1900-2500 Hz is observed. [ABSTRACT FROM AUTHOR]

Sawing is a commonly utilized undercutting process for machining in the steel and forging industries. With the continuous improvement of modern processing requirements and increasing demands for higher sawing efficiency, accuracy, and surface quality of workpieces, bi-metal band saw blades are facing greater challenges. In addition, the development of new and difficult-to-cut materials such as nickel-based alloys, titanium alloys, and other heterogeneous alloys has presented novel challenges to band sawing technology. However, the wear of the band saw blade has become a major hindrance to the application and development of sawing processing technology for new materials, high efficiency, high precision, etc. Based on the principle of metal cutting using a band saw blade and considering the wear process of teeth, this paper provides a comprehensive analysis of the impact of cutting parameters, cutting fluid, heat treatment, and surface treatment technology on tooth wear. Additionally, measures to enhance wear resistance are summarized. Furthermore, an overview is presented regarding the latest advancements in monitoring wear for bi-metal band saw blades. Finally, the future direction of research on wear in bi-metal band saw blades is anticipated. [ABSTRACT FROM AUTHOR]

The band saw blade, used on the wood log cutting, is exposed in service manufacturing to applications which can cause mechanical damages and affect the quality of the tool and the wood produced. To related applications, the shear stress is essential to the correct wood machining. the proposal of this paper was the numerically analyze the influence of the parallel shear force, applied vertically at the saw blade tooth, in response to the normal longitudinal tensions (sy) in service. A numeric model was constructed, by using of the commercial software based on the Finite Elements Method (FEM). In a first analysis, only a tensile stress was applied to the model on the upper edge of the blade, the deformation results obtained were used in the secondary analysis, with the simultaneous application of vertical point loads on the saw teeth. [ABSTRACT FROM AUTHOR]

Cemented carbide circular saw blades are widely used in the metal and nonmetal manufacturing industry for cut-off and cut-tail production. High energy consumption and intense noise emission from conventional-type blades are urgent environmental issues to be solved. Hence, a laminated-resin blade is proposed to study the effect of adding a damping structure to the blade body on its cutting performance. Apart from reduced energy consumption, lower noise and high-quality surfaces are required by manufacturers. In this work, a laminated-resin blade and a conventional blade were compared regarding the details of cutting force and energy consumption, noise emission, and surface integrity. In addition, the effect of cutting fluid on conventional saw blades was analyzed in terms of cutting force and noise emission. Experimental results show that the cutting force and noise of the laminated-resin blade were less than that of the conventional one, indicating reductions of 27.8% and 18 dB, respectively. Especially a reduction of more than 20 dB sound level was achieved in the high-frequency band. Lower cutting force attained by the laminated-resin blade showed that smoother cuts could be achieved. Cutting with cutting fluid is superior to dry cutting in cutting performance. The research sheds new light on the design of damping structures on saw blade bodies and quantitative analysis of the cutting performance. [ABSTRACT FROM AUTHOR]

Several studies have been conducted to reduce the idling noise of circular saws because the sound level is extremely high and harms the environment. However, conventional noise suppression technology only controls the vibrations of the circular saw itself, whereas idling noise can be generated when the air inside the enclosure is resonant. In this study, the relationship between the rotational speeds of the circular saw blade and the frequencies of the resonance sound when the circular saw blade is running idle in an enclosure was examined. Additionally, the sound pressure modes and frequencies of the air in the enclosure were analyzed using the finite element method of acoustic analysis. The results showed that resonance sound was generated only when the circular saw blade was enclosed. The frequencies of the resonance sound generated by a circular saw blade made of acrylic plastic were the same as those generated by a steel saw blade. The resonance sound was generated regardless of the outer diameter of the circular saw blade. The peak resonant frequencies formed a step-like line during the analysis in which the rotational speed of the saw blade was steadily increased. [ABSTRACT FROM AUTHOR]

Bone sawing is one of the most common operations during traditional dental and cranio-maxillofacial surgery and training systems based on virtual reality technology. It is necessary to predict and update conditions (including the sawing force, temperature and tool wear) in real time during VR surgical training and surgical simulation. All the specimens used in this study were fresh bovine scapula. The forces and temperatures were measured during the sawing process. Additionally, the thermal conductivity was measured via a laser flash instrument. Response surface methodology (RSM) was adopted to analyze and model the sawing force and sawing temperature. Meanwhile, tool wear was observed using a scanning electron microscope. The regression models of the sawing force and temperature rise under different experimental conditions were acquired. To obtain the minimum force within the recommended parameter ranges of commonly used medical reference parameters for bone sawing, a higher rotational speed combined with a lower feed rate were recommended. When considering the sawing force and temperature rise comprehensively, the rotational speed should not be extremely high (about 13,000 rpm is recommended). Meanwhile, abrasive wear is the main wear mode of saw blades. In order to avoid surgery failure, it is necessary to replace the saw blade in time. The experimental data were confirmed to be scientific and accurate for the predicted models of sawing conditions. To minimize the main cutting force, a feed rate of 40 mm/min combined with a rotational speed of 13,700 rpm is recommended. High cutting temperatures have the potential to cause irreversible tissue damage, so surgeons using dental reciprocating saws need to avoid excessively high-speed gears. [ABSTRACT FROM AUTHOR]

Objective: Field amputations are a low-frequency, high-risk procedure. Many prehospital personnel utilize the reciprocating saw. This study compares the efficiency, speed, and degree of tissue damage of different reciprocating saw blades found commercially. Methods: Amputations were performed on two human cadavers at different levels of the upper and lower extremities. Four different blades were used, each with a different teeth-per-inch (TPI) design. The amputations were timed, blade temperature was recorded, subjective operator effort was obtained, amount of splatter was evaluated, and an orthopedic physician evaluated the extent of tissue damage and operating room repair difficulty. Results: The blade with fourteen TPI was superior in overall speed to complete the amputations at 1.07 seconds per one centimeter of tissue (SD = 0.49 seconds) and had the lowest fail rate (0/8 amputations). The three TPI, six TPI, and ten TPI blades all required a "rescue" technique and were slower. The blade with fourteen TPI caused the least amount of tissue damage and was deemed the easiest to repair. Secondary outcomes demonstrated the fourteen TPI blade had generated the least amount of heat and produced the least amount of splatter. All blades had a perceived effort of "easy" to complete the amputation. Conclusion: While all blades were able to achieve an amputation, the overall recommendation is use of a fourteen TPI blade. It did not require any rescue techniques, provided the most straightforward amputation to repair, had the least amount of biohazard splatter and temperature increase, and was the fastest blade overall. [ABSTRACT FROM AUTHOR]

There are many complicated factors affecting sawing of wood structural component, so it is difficult to measure and evaluate accurately. In this study, the sawing speed of the wood component, the tooth shape of the circular saw blade, the number of teeth, and the wood component material were selected as the test factors to explore their influence on the sawing performance. Based on the multi-factor orthogonal test analysis method, the visual analysis method was used to comprehensively explore the impact of rotary speed of 1 000, 2 000, 3 000 r/min, circular saw blade flat teeth, ladder flat teeth, left and right teeth, number of teeth 60, 96, 120, spruce, fiberboard and bamboo scrimber on the cutting performance of wood components. The sawing-cutting power of wood components was used as the evaluation index of sawing-cutting performance of wood components, and multiple groups of experimental analysis were carried out to determine the best sawing scheme of wood components under different materials. The results showed that: 1) the primary and secondary order of the influence of each test factor on the maximum power consumption in the sawing process was: circular saw blade speed, specimen material, circular saw blade teeth number, circular saw blade teeth shape. The optimal process for sawing spruce was 1 000 r/min, 60 teeth and flat tooth shape. 2) The optimal process for sawing fiberboard was 1 000 r/min, 96 teeth and ladder flat teeth. 3) The optimal process for sawing bamboo scrimber was 2 000 r/min, 60 teeth and flat tooth shape. [ABSTRACT FROM AUTHOR]

In response to the problems of low efficiency and difficulty of pruning operations in modern dwarf dense orchards, an adjustable position saw blade pruning machine was designed, mainly consisting of a pruning device, a regulating device and a hydraulic system. Through the mechanical and modal analysis of the circular saw blade, the limit speed of the circular saw blade was derived. A finite element model of the sawing process was established, and a single-factor simulation analysis was conducted for three important parameters: feed rate, circular saw blade speed and branch diameter, and a three-factor, three-level quadratic regression orthogonal test was designed to derive the best matching sawing parameters, which was verified in field tests. The test results showed that the average passing rate was 92.8% at the feed rate of 4 km/h under the circular saw blade speed of 2800 rpm, which was higher than 88.8% at 3 km/h and 88.9% at 5 km/h. The optimum sawing parameters were: the circular saw blade speed of 2800 rpm and feed rate of 4 km/h, which were consistent with the simulation results, and the passing rate of the cut was high at this time, meeting the technical requirements of orchard pruning. [ABSTRACT FROM AUTHOR]