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Stab-resistant body armor (SRBA) is used to protect the body from sharp knives. However, most SRBA materials currently have the disadvantages of large weight and thickness. This paper aims to prepare lightweight and high-performance SRBA by 3D printing truss structure and resin-filling method.

The stab resistance truss structure was prepared by the fused deposition modeling method, and the composite structure was formed after filling with resin for dynamic and quasi-static stab tests. The optimized structural plate can meet the standard GA68-2019. Digital image correlation technology was used to analyze the local strain changes during puncture. The puncture failure mode was summarized by the final failure morphologies. The explicit dynamics module in ANSYS Workbench was used to analyze the design of the overlapped structure stab resistance process in this paper.

The stab resistance performance of the 3D-printed structural plate is affected by the internal filling pattern. The stab resistance performance of 3D-printed structural parts was significantly improved after resin filling. The 50%-diamond-PLA-epoxy, with a thickness of only 5 mm was able to meet the stab resistance standard. Resins are used to increase the strength and hardness of the material but also to increase crack propagation and reduce the toughness of the material. The overlapping semicircular structure was inspired by the exoskeleton structure of the demon iron beetle, which improved the stab resistance between gaps. The truss structure can effectively disperse stress for toughening. The filled resin was reinforced by absorbing impact energy.

The 3D-printed resin-filled truss structure can be used to prepare high-performance stab resistance structural plates, which balance the toughness and strength of the overall structure and ultimately reduce the thickness and weight of the SRBA.

This paper aims to design a composite, aiming to improve the static puncture resistance through polyurethane impregnated treatment with five concentration gradients.

The relationship between polyurethane concentration, the number of polyester nonwovens, component fiber type (filament or staple) and the static puncture resistance is explored respectively and elaborately.

This study provides a new perspective to design flexible composites with better static puncture resistance, feasible preparation process as well as low cost.

The results show that the static puncture resistance of nonwovens impregnated by polyurethane is improved obviously. Meanwhile the puncture strength-T of nonwovens increases first and then decreases with the increase of the number of layers, and the maximum puncture strength-T is found at 20 layers. Moreover, the composite with filaments illustrates better mechanical resistance.

The purpose of this paper is to propose a robotic system for percutaneous surgery. The key component in the system, a robotic arm that can manipulate a puncture needle is presented. The mechanical design, the motion control and the force control method of the robotic arm are discussed in the paper.

The arm with an arc mechanism placed on a 3D Cartesian stage is developed as a puncture needle manipulator to locate the position of the needle tip, tune the needle’s posture and actuate the puncture motion under the visual guidance of two orthogonal X-ray images of a patient by a surgeon. A focusing method by using two laser spots is proposed to automatically move the needle tip to a surgery entry point on the skin. A dynamics model is developed to control the position of the needle mechanism and an explicit force control strategy is utilized to perform the needle insertion.

With the surgical system, a surgeon can easily perform puncture operation by taking two orthogonal real-time X-ray images as a visual feedback and accurately navigating the needle insertion. The laser-guided focusing method is efficient in placement of the needle tip. The explicit force control strategy is proved to be effective for holding constant and stable puncture force in experiments.

The robotic arm has an advantage in easy redirection of the needle because the rotation and the translation are decoupled in the mechanism. By adopting simple laser pens and a well-developed kinematics model, the system can handle the entry point, locating task automatically. The focusing method and the force control method proposed in the paper are useful for the present system and could be intuitive for similar surgical robots.

In line with the fast development of information technology, the Internet of Medical Robotic Things (IoMRT) is gaining more ground in health care. Sharing patients' information effectively and securely can improve sensing data usage and confidentiality. Nevertheless, current IoMRT data sharing schemes are lacking in terms of supporting efficient forward secrecy; when secret key for a robotic nurse as a data requester is compromised, all the historically shared data with this robotic nurse will be leaked.

The presented paper suggests an efficient puncturable attribute-based data sharing scheme enabling guaranteed firm security and versatile access control over health sensing data in IoMRT. This scheme integrates attribute-based and puncturable encryption to avail a shared secret key for data sharing that can be encrypted by an access structure over the Data Requester (DR) attributes. Additionally, the establishment of the shared key and the mutual authentication is simultaneously done between the cloud servers and DRs.

The proposed scheme can achieve forward secrecy by adopting the bloom filter technique that efficiently helps the updating of a private key with no need for the key distributor to reissue the key. The security proof illustrates that this scheme adheres to the security model. Besides, the performance evaluation expresses the feasibility of the suggested scheme.

The main goal of designing a puncture algorithm is to devise an updated key from the ciphertext and a secret key, allowing the decryption of all ciphertexts except the one that has been punctured on. This research illustrates the first effort to develop a puncturable attribute-based encryption scheme to achieve efficient finegrained data sharing in IoMRT.

This study aims to determine the effect of aromatherapy used in reducing the pain caused by fistula puncture in hemodialysis patients.

In this study, the effect of aromatherapy application on fistula puncture was analyzed and carried out by scanning the relevant literature. The literature review was conducted between August and October 2020. While reviewing the literature, the authors used “aromatherapy,” “pain,” “fistula,” “puncture,” “hemodialysis” keywords and various combinations of these; moreover, Google scientist, Pubmed, Cochrane, ScienceDirect, Web of Science, Medline and Ovid databases and studies, which were conducted in the last 10 years were reviewed. As a result of the literature review, 1183 studies were reached and seven of them were included in the study by taking the inclusion criteria into account.

The randomized controlled studies are six studies and nonrandomized controlled experimental 1 study were added to the scope of the study and seven studies were included in the sample. In these studies, personal information forms developed by the researchers as data collection tools and the VAS scale, Numerical pain rating, the numeric rating scale were used to evaluate pain.

It has been determined that aromatherapy application in hemodialysis patients has positive effects on reducing pain due to puncture fistula intervention.

This study provides reduction or elimination of fistula needle insertion pain in hemodialysis patients.

The purpose of this paper is to propose a statistical approach, which enables the prediction of the risk of the appearance of discharge bearing currents in a given drive that can damage the motor bearings. Using such an approach, the drives for the decisive but expensive, long‐term destructive investigations can be selected. A comparative analysis is presented to show the applicability of the presented statistical model.

In the paper, a statistical approach to large data sets of measured bearing currents is presented. Weibull distribution has been chosen to describe the amplitudes of bearing currents, whereas exponential distribution is used for the approximation of the awaiting times to puncture. In order to check the hypothesis that these distributions are independent two tests has been conducted: F‐Snedecor, to check equality of mean values and Bartlett's to check variance equality. On this basis, joint distribution is expressed as the product of independent marginal distributions.

The comparative analyses show that special caution is required for a proper selection of EMI filters. The additional inductance of the filter in a common mode (CM) current path decreases the damping factor of the circuit and significantly increases the risk of bearing damage caused by electric discharge machining currents. The CM transformer is a cheap and effective solution that reduces CM current without increasing the rate and the amplitudes of bearing currents.

This paper presents a new approach to bearing currents that allows prediction of the risk of bearing damage in a given drive.

This paper aims to estimate the performance of protective clothing used to resist puncture (anti-stab property).

Seven single-layer (one layer) samples were investigated in this research. The first three samples were already used for the purpose of (anti-stab property), manufactured from Du-Pont product (commercial samples). The rest of the samples were locally designed and manufactured for the same purpose. These seven samples have then been examined after been added in conjunction with WL Kevlar XP (S 104) witness multilayers (eight layers) panel to create which are called multilayer samples.

The results of the statistical analysis for one-way ANOVA illustrated significant effect for single layer samples for all properties. While for multi-layer samples, the results showed a significant difference for all variables except displacement. The Tukey post hoc test observed a significant effect for some samples; also, other samples show a non-significant effect between samples.

It was observed that the locally manufactured samples serve the purpose as (anti-stab samples) compared with the commercial samples. The radar chart shows that for single-layer sample, the fifth sample fulfill the highest radar chart area, whereas for multi-layer samples, the sixth sample achieved the highest radar chart area.

With the increasing development of the surgical robots, the opto-mechatronic technologies are more potential in the robotics system optimization. The optic signal plays an important role in opto-mechatronic systems. This paper aims to present a review of the research status on fiber-optic-based force and shape sensors in surgical robots.

Advances of fiber-optic-based force and shape sensing techniques in the past 20 years are investigated and summarized according to different surgical requirement and technical characteristics. The research status analysis and development prospects are discussed.

Compared with traditional electrical signal conduction, the phototransduction provides higher speed transmission, lower signal loss and the immunity to electromagnetic interference in robot perception. Most importantly, more and more advanced optic-based sensing technologies are applied to medical robots in the past two decades because the prominence is magnetic resonance imaging compatibility. For medical robots especially, fiber-optic sensing technologies can improve working security, manipulating accuracy and provide force and shape feedback to surgeon.

This is a new perspective. This paper mainly researches the application of optical fiber sensor according to different surgeries which is beneficial to learn the great potential of optical fiber sensor in surgical robots. By enumerating the research progress of medical robots in optimization design, multimode sensing and advanced materials, the development tendency of fiber-optic-based force and shape sensing technologies in surgical robots is prospected.

The paper aims to use the Trilobal® polyester (Y cross-section) for producing fabrics suitable for fencing suits and evaluating their various properties.

Double weave structure was chosen to produce the samples by using six different face structures and two back structures divided into two groups according to the back structures. They were evaluated by their physical and mechanical properties such as tensile strength, puncture resistance, air permeability and humidity properties in horizontal and vertical wicking, drying rate and water vapor transmission.

Fencing sport recently is one of the most growing sports in the world, which necessitates special requirements and properties of fencing suit, either mechanical properties, which allow the easily and freely movement for the athlete, or the comfort properties that save the player’s effort and energy for a long time to improve his performance.

ANOVA test analysis showed highly significant results in some properties comparing back and face structures of the double weave fabric high correlation coefficient were found between packing density factor of produced fabric and the weft material types. The final results showed the produced sample that weaved with plain 1/1 for back structure and warp rib 2/2 for face structure achieved the best results, followed by the produced sample weaved with plain 1/1 for back structure and weft rib 2/2 for face structure compared with the other produced samples.

AFTER BRIEFLY considering the surface areas of aircraft for which lightning strikes are a major factor in the selection of constructional materials, a review is made of published information concerning the effects of lightning on these various materials. The materials are considered under three headings: metallic, non‐conducting (e.g. glass‐fibre‐reinforced‐plastics) and semi‐conducting (e.g. carbon‐fibre‐reinforced plastics). Simulated lightning current tests are the main source of information and the review is primarily concerned with the results of such tests. To aid assessment of the relevance of the test currents that have been used, an outline of the current characteristics of lightning discharges is also given.