Attachment Devices Research Articles

Incline-dependent adjustments of toes in geckos inspire functional strategies for biomimetic manipulators

Geckos show versatility by rapidly maneuvering on diverse complex terrain because they benefit from their distributed, setae-covered toes and thus have the ability to generate reliable and adaptive attachment. Significant attention has been paid to their adhesive microstructures (setae), but the effectiveness of the gecko’s adaptive attachment at the level of toes and feet remains unclear. In order to better understand the geckos’ attachment, we first focused on the deployment of toes while challenging geckos to locomote on varying inclines. When the slope angle was less than 30°, their feet mainly interacted with the substrate using the bases of the toes and generated anisotropic frictional forces. As the slope angle increased to 90°, the participation of the toe bases was reduced. Instead, the setae contribution increased for the middle three toes of the front feet and for the first three toes of the hind feet. As the incline changed from vertical to inverted, the adhesive contribution of the toes of the front feet became more equal, whereas the effective adhesion contact of the hind feet gradually shifted to the toes oriented rearwards. Second, a mathematical model was established and then suggested the potential advantages of distributed control among the toes to regulate foot force. Finally, a physical foot model containing five compliant, adjustable toes was constructed and validated the discoveries with regard to the animals. Using the gecko toes’ control strategies, the artificial foot demonstrated diverse behavior regulating attachment forces. The success of the foot prototype not only tested our understanding of the mechanism of biological attachment, but also provided a demonstration for the design and control of gecko-inspired attachment devices, grippers and other manipulators.

Home-based transcutaneous tibial nerve stimulation for overactive bladder syndrome: a randomized, controlled study.

PurposeTranscutaneous posterior tibial nerve stimulation (TPTNS) for the treatment of overactive bladder syndrome (OAB), with or without urge urinary incontinence (UUI) using electrodes imbedded in the fabric of a conventional sock and an attachable battery-operated stimulation device (ZIDA®—Exodus Innovations, Sufa, Israel), was compared for effectiveness and safety to a sham procedure in a prospective, blinded, randomized, controlled trial.MethodsForty patients with diagnosed with OAB were recruited from a single site. There were two groups: a treatment group (21 patients, mean age 64), which used an active ZIDA® activation device (ZIDA) and a sham control group (SCG, 19 patients, mean age 72) randomized in a 1:1 ratio. After individual fitting of the sock and face-to-face instruction in the use of the device, patients in both groups self-administered the treatment once weekly for 30 min at home for a duration of 12 weeks. Prior to randomization and in Week 12, patients completed two 3-day bladder diaries and a quality-of-life (QOL) survey. Treatment success was defined as at least a 50% reduction in urgency voids with or without incontinence or at least a 30% reduction in 24-h frequency from baseline to Week 12. The key secondary endpoint was change in QOL from baseline to Week 12.ResultsThe success rate for the primary endpoint in the ZIDA group was 80% (n = 16/20) versus 39% (n = 7/18) in the SCG (p = 0.02). For QOL, the least squares mean difference in change from baseline to Week 12 between the ZIDA and sham control arms total score was − 12.7 (95% CI − 20.2 to − 5.1). No significant adverse effects were observed.ConclusionTPTNS using the ZIDA home-based stimulation device offers a safe and effective treatment for patients with OAB syndrome and improves QOL. Trial regestrationTRN: NCT04470765.

Improved adenoma detection by a novel distal attachment device-assisted colonoscopy: a prospective randomized controlled trial

WingCap (A&A Medical Supply LLC, Seongnam, South Korea) is a novel distal attachment device for colonoscopy that combines a cap and an existing mucosal exposure device, such as Endocuff Vision (Arc Medical Design Ltd, Leeds, UK) and AmplifEYE (Medivators Inc, Minneapolis, Minn, USA). We aimed to investigate whether WingCap-assisted colonoscopy can improve the adenoma detection rate (ADR) and adenoma per colonoscopy (APC) and simultaneously shorten cecal intubation time compared with standard colonoscopy. We conducted a single-center, prospective, randomized controlled trial for outpatients aged≥18 years undergoing colonoscopy. The primary outcome was ADR differences with the assistance of WingCap. Secondary outcomes were APC and other colonoscopy quality indicators, such as cecal intubation and withdrawal times. In total, 537 patients were randomized for WingCap-assisted or standard colonoscopy. Their mean age was 59.3 years, and 48.5% were men. ADR was significantly higher in the WingCap group than in the control group (37.2% vs 26.6%, P= .012). APC was greater with WingCap than with standard colonoscopy (.72 ± 1.34 vs .45 ± 0.97, P= .008), prominently for nonpedunculated (.65 ± 1.25 vs .42 ± .95, P= .015) and diminutive (.42 ± .94 vs .20 ± .64, P= .002) adenomas. With WingCap, ADR and APC significantly increased for beginner endoscopists, whereas a modest increase was seen for experienced endoscopists. There were no differences in cecal intubation and withdrawal times between the 2 arms. No serious adverse event was associated with the use of WingCap. WingCap-assisted colonoscopy was tolerable and efficacious for improving ADR and APC compared with standard colonoscopy, especially for nonpedunculated and diminutive adenomas and for beginner endoscopists. (Clinical trial registration number: KCT0005214.).

Remote Sensing System for Motor Nerve Impulse.

In this article, we present our research achievements regarding the development of a remote sensing system for motor pulse acquisition, as a first step towards a complete neuroprosthetic arm. We present the fabrication process of an implantable electrode for nerve impulse acquisition, together with an innovative wirelessly controlled system. In our study, these were combined into an implantable device for attachment to peripheral nerves. Mechanical and biocompatibility tests were performed, as well as in vivo testing on pigs using the developed system. This testing and the experimental results are presented in a comprehensive manner, demonstrating that the system is capable of accomplishing the requirements of its designed application. Most significantly, neural electrical signals were acquired and transmitted out of the body during animal experiments, which were conducted according to ethical regulations in the field.

Preclinical Assessment of a Rapid Anastomotic Device for HeartMate 3 Apical Cuff Implantation

<h3>Purpose</h3> The HeartMate3 (HM3) LVAD requires an apical cuff (AC) to left ventricle (LV) anastomosis. We developed an AC attachment device for the standard HM3 AC with 12 anchors and 4 compression plates. A Gen1 delivery tool requires a hand-held driver and sequential anchor delivery. A Gen2 delivery tool with a targeting system and improved anchors has a planetary gear mechanism that drives all anchors simultaneously. The study purpose was to assess functionality and hemostasis of HM3 AC anastomosis. <h3>Methods</h3> Standard HM3 ACs were implanted without cardiopulmonary bypass (CPB) in 8 calves (110 to 130 kg): left thoracotomy (n=2), median sternotomy (n=6). Implant time was from epicardial contact to complete anchor deployment. Blood pressure (BP) was measured by arterial line. After anchor deployment and AC attachment heparin was administered to ACT over 400 seconds. Fibrillation (n=2), rapid pacing (n=1) and vena cava inflow occlusion (n=5) were used for LV coring and custom AC plug insertion with resuscitation to baseline BP. Functionality and hemostasis were qualitatively assessed. Supraphysiologic testing (norepinephrine, 0.15 mcg/kg/min) was assessed in 4 cases (Gen1, n=3; Gen2, n=1). <h3>Results</h3> Implants were simple. Gen1 (n=6) implant time range was 63 to 94 seconds. Gen2 (n=2) times were 26 and 32 seconds. Prior to anticoagulation hemostasis was excellent. Five cases were assessed for post-plug hemostasis (2 fibrillated and 1 paced could not be resuscitated). After resuscitation there was minimal to no bleeding in 3 cases (2 Gen 1, 1 Gen 2). In 2 cases (1 Gen1, 1 Gen2) sutures were required at a single anchor site: 1 Gen1 had localized bleeding due to a single anchor failure (cap separation), 1 Gen2 had bleeding at a coronary artery perforation. Excellent hemostasis was maintained at supraphysiologic pressures (n=4, systolic BP range 211-248 mmHg). <h3>Conclusion</h3> Rapid HM3 apical cuff attachment is feasible. Hemostasis was excellent even at significant supraphysiologic blood pressure. Advantages are: 1) No HM3 AC manufacturing changes are required, 2) Implant time is greatly decreased, 3) Implant is easy without CPB, 4) Implant site targeting is precise, 5) The area of impacted myocardium is limited to the area under the AC sewing skirt, and 6) Low device profile permits use with mini-thoracotomy access. Suturing buttressing is feasible and may be necessary in case of coronary artery perforation.

The effects of substrate porosity, mechanical substrate properties and loading conditions on the attachment performance of the Mediterranean medicinal leech (Hirudo verbana).

The ectoparasitic lifestyle of the Mediterranean medicinal leech (Hirudo verbana) requires reliable functioning of its attachment organs (i.e. anterior and posterior suction discs) on multiple habitat- and host-specific surfaces under both normal and shear stresses. In addition to some intrinsic properties of the attachment devices, however, only a few extrinsic factors (e.g. substrate roughness and porosity) have been considered in previous studies on leech suckers. Using centrifugal force experiments, we analysed the attachment performance of H. verbana under different types of loading on artificial substrates differing in porosity and their mechanical properties. Whereas the substrate porosity significantly influenced leech attachment under normal and shear loading, the different mechanical properties did not noticeably affect attachment within the considered parameter limits. Furthermore, suction was confirmed to be the primary attachment mechanism independent of the prevailing loading condition. The question of whether the suction cups of H. verbana are adapted to a specific loading condition could not be answered. In any case, our results again highlight the high functional resilience of leech suckers guaranteeing a successful ectoparasitic lifestyle.

Like parent, like child – Ontogenetic development of claws of intertidal arthropods (Acari, Oribatida) from different ecological niches

The shape of claws of adult air-breathing intertidal oribatid mites shows a strong correlation with ecology. As nothing is known about juvenile characteristics of this trait, the ontogenetic development of these attachment devices was studied for the first time with comprehensive geometric morphometric methods. In nine investigated species, claws of immature stages can be classified into the same ecological categories as adults, i.e. juveniles of several rock-dwelling species already show higher and stronger curved claw shapes with smaller claw angles, while juvenile instars of the single investigated mangrove-dwelling species possess lower and less curved claws with wider claw angles. For each species, claw curvature is almost static during the complete development and claw length grows directly proportional with increasing body size. Developmental changes in body size and weight are thus mainly compensated by a simple relative growth in size. Despite the finding that claw shapes of early developmental stages are already classifiable into ecological categories, their shapes also change slightly during development to become more ‘rock’, ‘mix’ or ‘mangrove’-like, respectively. The present results demonstrate that ecology is also the most important factor in shaping the claws of immatures and that attachment in the intertidal environment is vital for the survival of each mobile stage.

Phoresy Involving Insects as Riders or Rides: Life History, Embarkation, and Disembarkation

AbstractThe ability to disperse is vital for all organisms, but especially for those whose habitats deteriorate, necessitating relocation to better feeding or breeding sites. Phoresy is assisted dispersal in which one organism uses another as its vehicle. In this review, phoresy will be largely restricted to cases wherein the rider is not parasitic on the vehicular stage used for dispersal, and in which insects are riders or rides. Phoresy occurs in organisms with limited mobility, and in secondarily brachypterous or completely wingless insects. Intraspecific phoresy also occurs. Generally, immature stages resistant to environmental assaults, such as dauers in nematodes, triungulins in beetles, or deutonymphs in mites, undertake phoresy. A size differential between rider and rider enables several conspecifics to board the same vehicle, likely ensuring mating opportunities at the destination. Riders may have special attachment devices or adhesive secretions to ensure safety during travel. Life cycles of riders and vehicles are often synchronized, and when phoresy is mutualistic, vehicles may also employ chemical tactics to achieve this synchrony. Chemical cues help to identify the appropriate vehicle, for disembarkation, or to lure the vehicle towards riders. Most riders prefer female vehicles, possibly to ensure access to rich nesting sites. Density-dependent selection may operate to limit the number of riders on a vehicle and phoresy may also facilitate sexual selection among riders. Whether vehicles can avoid phoresy is barely understood. This review attempts to place phoresy within a broad evolutionary context and points out the paucity of knowledge in certain research areas.

High-Definition Colonoscopy Compared With Cuff- and Cap-Assisted Colonoscopy: Results From a Multicenter, Prospective, Randomized Controlled Trial

Mucosal exposure devices including distal attachments such as the cuff and cap have shown variable results in improving adenoma detection rate (ADR) compared with high-definition white light colonoscopy (HDWLE). We performed a prospective, multicenter randomized controlled trial in patients undergoing screening or surveillance colonoscopy comparing HDWLE to 2 different types of distal attachments: cuff (CF) (Endocuff Vision) or cap (CP) (Reveal). The primary outcome was ADR. Secondary outcomes included adenomas per colonoscopy, advanced adenoma and sessile serrated lesion detection rate, right-sided ADR, withdrawal time, and adverse events. Continuous variables were compared using Student's t test and categorical variables were compared using chi-square or Fisher's exact test using statistical software Stata version16. A P value <.05 was considered significant. A total of 1203 subjects were randomized to either HDWLE (n= 384; mean 62 years of age; 81.3% males), CF (n= 379; mean 62.7 years of age; 79.9% males) or CP (n= 379; mean age 62.1 years of age; 80.5% males). No significant differences were found among 3 groups for ADR (57.3%, 59.1%, and 55.7%; P= .6), adenomas per colonoscopy (1.4 ± 1.9, 1.6 ± 2.4, and 1.4 ± 2; P= .3), advanced adenoma (7.6%, 9.2%, and 8.2%; P= .7), sessile serrated lesion (6.8%, 6.3%, and 5.5%; P= .8), or right ADR (48.2%, 49.3%, and 46.2%; P= .7). The number of polyps per colonoscopy were significantly higher in the CF group compared with HDWLE and CP group (2.7 ± 3.4, 2.3 ± 2.5, and 2.2 ± 2.3; P= .013). In a multivariable model, after adjusting for age, sex, body mass index, withdrawal time, and Boston Bowel Preparation Scale score, there was no impact of device type on the primary outcome of ADR (P= .77). In screening patients, CF resulted in more neoplasms per colonoscopy (CF: 1.7 ± 2.6, HDWLE: 1.3 ± 1.7, and CP: 1.2 ± 1.8; P= .047) with a shorter withdrawal time. Results from this multicenter randomized controlled trial do not show any significant benefit of using either distal attachment devices (CF or CP) over HDWLE, at least in high-detector endoscopists. The Endocuff may have an advantage in the screening population. (ClinicalTrials.gov, Number: NCT03952611).

New high fidelity (hi-fi) three-dimensional thermophone CNT sponge

A novel, high-fidelity (hi-fi) thermophone based on three-dimensional porous CNT sponge is designed for attachable and wearable sound generation devices. In addition to its simple structure and easy fabrication, CNT sponge thermophone exhibits excellent thermoacoustic and mechanical characteristics, particularly its wideband frequency response, due to its highly efficient energy conversion capability through the CNT nano-structural materials. In this paper, the hi-fi sound response of suspended CNT sponge thermophones is analyzed by theory and experiment. A theoretical thermoacoustic model for CNT sponge thermophone is proposed and the corresponding analytical solutions are established. To explore applications of CNT sponges, a flexible thermophone and a hi-fi thermoacoustic loudspeaker are developed and investigated by experiment. The flexible CNT sponge thermophone presents stable sound response before and after it is attached to some complicated surfaces. The CNT sponge thermoacoustic loudspeaker shows a wide bandwidth, high-quality audio output, and stable sound response. Such premium characteristics ensure its feasibility as a potential replacement for the conventional voice coil and piezoelectric loudspeakers.

Evaluation of facial tissue stresses under medical devices post application of a cyanoacrylate liquid skin protectant: An integrated experimental-computational study.

Medical device‐related pressure ulcers (PUs) (injuries) are a subclass of PUs, associated with pressure and/or shear applied by a medical device onto the skin. Clinical application of a cyanoacrylate liquid skin protectant (CLSP) under the contours of skin‐contacting medical devices to shield an intact skin from the sustained mechanical loads that are applied by medical devices is a preventative option, but no computer modelling work has been reported to assess the biomechanical efficacy of such interventions. Here, we investigated the biomechanical protective effect of a polymerised cyanoacrylate coating using three‐dimensional, anatomically realistic finite element models of the ear with oxygen cannula and the mouth with endotracheal attachment device, informed by experimental studies. We have compared tissue stress exposures under the devices at these facial sites between conditions where the cyanoacrylate skin protectant has been applied or where the device was contacting the skin directly, without the shielding of the cyanoacrylate coating. The CLSP considerably reduced the skin stress concentration levels and overall tissue stress exposures under the aforementioned medical devices. This demonstrates strong biomechanical effectiveness of the studied cyanoacrylate‐based skin protectant in prevention of facial medical device‐related injuries at small, curved and thereby difficult to protect facial sites.

Computer-aided detection versus advanced imaging for detection of colorectal neoplasia: a systematic review and network meta-analysis

Computer-aided detection (CADe) techniques based on artificial intelligence algorithms can assist endoscopists in detecting colorectal neoplasia. CADe has been associated with an increased adenoma detection rate, a key quality indicator, but the utility of CADe compared with existing advanced imaging techniques and distal attachment devices is unclear. For this systematic review and network meta-analysis, we did a comprehensive search of PubMed/Medline, Embase, and Scopus databases from inception to Nov 30, 2020, for randomised controlled trials investigating the effectiveness of the following endoscopic techniques in detecting colorectal neoplasia: CADe, high definition (HD) white-light endoscopy, chromoendoscopy, or add-on devices (ie, systems that increase mucosal visualisation, such as full spectrum endoscopy [FUSE] or G-EYE balloon endoscopy). We collected data on adenoma detection rates, sessile serrated lesion detection rates, the proportion of large adenomas detected per colonoscopy, and withdrawal times. A frequentist framework, random-effects network meta-analysis was done to compare artificial intelligence with chromoendoscopy, increased mucosal visualisation systems, and HD white-light endoscopy (the control group). We estimated odds ratios (ORs) for the adenoma detection rate, sessile serrated lesion detection rate, and proportion of large adenomas detected per colonoscopy, and calculated mean differences for withdrawal time, with 95% CIs. Risk of bias and certainty of evidence were assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. 50 randomised controlled trials, comprising 34 445 participants, were included in our main analysis (six trials of CADe, 18 of chromoendoscopy, and 26 of increased mucosal visualisation systems). HD white-light endoscopy was the control technique in all 50 studies. Compared with the control technique, the adenoma detection rate was 7·4% higher with CADe (OR 1·78 [95% CI 1·44-2·18]), 4·4% higher with chromoendoscopy (1·22 [1·08-1·39]), and 4·1% higher with increased mucosal visualisation systems (1·16 [1·04-1·28]). CADe ranked as the superior technique for adenoma detection (with moderate confidence in hierarchical ranking); cross-comparisons of CADe with other imaging techniques showed a significant increase in the adenoma detection rate with CADe versus increased mucosal visualisation systems (OR 1·54 [95% CI 1·22-1·94]; low certainty of evidence) and with CADe versus chromoendoscopy (1·45 [1·14-1·85]; moderate certainty of evidence). When focusing on large adenomas (≥10 mm) there was a significant increase in the detection of large adenomas only with CADe (OR 1·69 [95% CI 1·10-2·60], moderate certainty of evidence) when compared to HD white-light endoscopy; CADe ranked as the superior strategy for detection of large adenomas. CADe also seemed to be the superior strategy for detection of sessile serrated lesions (with moderate confidence in hierarchical ranking), although no significant increase in the sessile serrated lesion detection rate was shown (OR 1·37 [95% CI 0·65-2·88]). No significant difference in withdrawal time was reported for CADe compared with the other techniques. Based on the published literature, detection rates of colorectal neoplasia are higher with CADe than with other techniques such as chromoendoscopy or tools that increase mucosal visualisation, supporting wider incorporation of CADe strategies into community endoscopy services. None.

Apexoconnection: A Novel Technique to Determine Working Length.

PurposeThe aim of this study was to evaluate and compare the accuracy of working length (WL) determination when using the conventional electronic WL (EWL) technique versus using the novel Apexoconnection technique involving EWL with a connector (EWLc).Materials and MethodsSixty extracted posterior teeth with a total of 118 root canals were selected for the study. The real WL (RWL) of each canal was verified using a dental microscope under 25.6x magnification. Root canal lengths were measured with an apex locator using the attachment device directly attached to the hand file in the root canal and then adding another hand file as a connector between the attachment device and the file in the root canal. The distance from the file’s stopper to its tip was measured using a digital caliper. Statistical analysis was carried out to analyze the data between experimental groups.ResultsThe results of the statistical test showed that the differences in the WL determined by either technique and the proper length as determined under the microscope were not statistically significant. The results of the statistical test comparing the groups were also not statistically significant.ConclusionIn this in vitro study, both the novel and conventional techniques were equally accurate for determining WL when compared with the RWL.

Reduction in Insect Attachment Caused by Different Nanomaterials Used as Particle Films (Kaolin, Zeolite, Calcium Carbonate)

In the present investigation, we compared the reduction in attachment ability of the southern green stinkbug Nezara viridula (Hemiptera: Pentatomidae) to glass induced by three different nanoparticle (kaolin, zeolite, and calcium carbonate) films. Using traction force experiments, behavioral experiments, and scanning electron microscopy observations, we analyzed the insect attachment ability and linear speed on untreated and treated glass with the three particle films. The three nanomaterials strongly reduced insect attachment ability mainly owing to contamination of attachment pads. The ability to reduce insect attachment was different for the three tested particle films: kaolin and zeolite induced a significantly higher reduction in N. viridula safety factor than calcium carbonate. The coating of the surface was more uniform and compact in kaolin and zeolite compared to calcium carbonate particle film. Moreover, kaolin and zeolite particles can more readily adhere to N. viridula attachment devices, whereas calcium carbonate particles appeared less adherent to the cuticular surface compared to the two aluminosilicate (kaolin and zeolite) particles. Only the application of kaolin reduced insect linear speed during locomotion. Nanoparticle films have a great potential to reduce insect attachment ability and represent a good alternative to the use of insecticides for the control of pentatomid bugs and other pest insects.

Physical constraints lead to parallel evolution of micro- and nanostructures of animal adhesive pads: a review.

Adhesive pads are functional systems with specific micro- and nanostructures which evolved as a response to specific environmental conditions and therefore exhibit convergent traits. The functional constraints that shape systems for the attachment to a surface are general requirements. Different strategies to solve similar problems often follow similar physical principles, hence, the morphology of attachment devices is affected by physical constraints. This resulted in two main types of attachment devices in animals: hairy and smooth. They differ in morphology and ultrastructure but achieve mechanical adaptation to substrates with different roughness and maximise the actual contact area with them. Species-specific environmental surface conditions resulted in different solutions for the specific ecological surroundings of different animals. As the conditions are similar in discrete environments unrelated to the group of animals, the micro- and nanostructural adaptations of the attachment systems of different animal groups reveal similar mechanisms. Consequently, similar attachment organs evolved in a convergent manner and different attachment solutions can occur within closely related lineages. In this review, we present a summary of the literature on structural and functional principles of attachment pads with a special focus on insects, describe micro- and nanostructures, surface patterns, origin of different pads and their evolution, discuss the material properties (elasticity, viscoelasticity, adhesion, friction) and basic physical forces contributing to adhesion, show the influence of different factors, such as substrate roughness and pad stiffness, on contact forces, and review the chemical composition of pad fluids, which is an important component of an adhesive function. Attachment systems are omnipresent in animals. We show parallel evolution of attachment structures on micro- and nanoscales at different phylogenetic levels, focus on insects as the largest animal group on earth, and subsequently zoom into the attachment pads of the stick and leaf insects (Phasmatodea) to explore convergent evolution of attachment pads at even smaller scales. Since convergent events might be potentially interesting for engineers as a kind of optimal solution by nature, the biomimetic implications of the discussed results are briefly presented.

Effect of Stretching on the Air Permeability of Recycled Polyester/Virgin Cotton and Its Blended Socks

Abstract Socks are considered to be one of the important accessories for humans in everyday life. Socks undergo irregular stretching in multiple directions during usage. The amount of stretching that occurs in socks is proportionate to the level of foot movement and the foot shape. The comfortability of socks lagely depends on the air permeability and thermal comfort properties. In general, the air permeability of the socks was measured in unstretched conditions. However, in real-time situations, the socks get stretched in multiple directions while being used. Stretch is one of the key factors that largely influences the air permeability of the socks. Few researchers have addressed this area; hence, the air permeability of the socks under various percentages of stretch is primarily focused on in this study. A novel automated fabric stretching attachment device was used to study the effect of stretching on the air permeability of recycled polyester/virgin cotton and its blended socks. The results were statistically investigated by two-way analysis of variance by using SAS 8.0. A statistical analysis proved that the effect of the stretching and blend ratio was statistically significant on the air permeability properties of socks.

Design of a dual safety device for excavator attachment

본 연구는 건설 현장과 기타 산업 현장에서 폭넓게 사용되는 굴삭기 부착장비 중 퀵 커플러의 탈착, 낙하사고 방지를 위한 안전장치 디자인에 관한 것이다. 굴삭기는 각 작업의 특성에 따라 버켓, 크랴샤, 쉐어 등의 장비를 부착해 사용하는데 부착장비의 빠른 교체를 위해 퀵 커플러가 사용된다. 이때 사용된 퀵 커플러는 부착장비의 탈착 및 장착 시간을 획기적으로 줄이지만 탈착과 낙하사고를 일으키는 주 요인이 되기도 한다. 이러한 문제들을 해결하기 위해서는 퀵 커플러의 이동후크가 연결핀을 구속할 수 있어야 하고, 부착장비 교체 후 안전장치가 자동으로 작동해 연결핀이 체결되도록 구성되어야 한다. 아울러 퀵 커플러의 이동후크가 동작해 부착장비의 연결핀을 구속하면 작업자의 의도와 상관없이 안전장치가 작동하고, 작업자의 실수나 판단 착오 등에 의해 안전장치가 해제되지 않아야 한다. 본 연구는 굴삭기 부착장비의 탈착 및 낙하사고를 방지하기 위한 해결방안을 찾기 위해 수행되었으며, 이번 연구를 통해 굴삭기 부착장비를 이용한 굴삭작업, 도로 정리 작업, 삼림작업, 제설작업, 상하차 작업 등 산업 현장에서 벌어질 수 있는 안전사고를 크게 줄일 수 있을 것으로 기대된다. 작업자의 안전의식이 부족해 사고가 발생한다는 접근만으로는 안전사고 차단이 어렵기 때문에, 근본적인 문제해결을 위한 디자인적인 솔루션을 도출하게 된 것이다. 이번 연구를 통해 작업자의 실수에 의한 사고가 줄어들 뿐만 아니라 작업의 편의성을 높여 생산성도 함께 개선될 것으로 기대하고 있다. 후속 연구에서는 굴삭기 부착장비 2중 안전장치 디자인으로 시제품을 제작해 실질적인 데이터를 기반으로 한 실증적인 분석연구가 진행될 계획이다.This study is about the design of safety devices to prevent the Quick coupler from detaching or falling, as one of the excavator attachments equipment widely used at construction sites and other industrial sites. The excavator is used by attaching equipment such as buckets, kryasha, shears depending on the characteristics of each work and the Quick coupler is used to quickly replace the attached equipment. At this time, the Quick coupler greatly reduces the detachable and mounted time of attachment equipment, but it can also be the main cause for detachable and falling accidents. To solve these problems, the Quick coupler s moving hook must be able to bind the connecting pin, and after equipment replacement, the safety device shall be operated automatically so that the connection pin is engaged. In addition, if the Quick coupler s moving hook will bind the connecting pin of the attachment equipment, the safety device should operate regardless of the operator s intention, and the safety device should not be released due to the operator s mistake or error in judgment. This study was conducted to find solutions to prevent detachment and fall accidents of excavator attachment equipment, and it is expected that this study will greatly reduce safety accidents at industrial sites such as excavation, road cleaning, deforestation, and up and down. Because it is difficult to block safety accidents just by approaching that accidents occur due to a lack of safety awareness of workers, design solutions for fundamental problem solving have been derived. Through this study, it is expected that not only will accidents caused by mistakes by workers be reduced, but also productivity will be improved by increasing the convenience of work. In a follow-up study, a prototype will be produced with a dual safety device design for excavator attachment equipment and empirical analysis research based on practical data will be conducted.

Detection of Varroa mites from honey bee hives by smart technology Var-Gor: a hive monitoring and image processing device

The major honey bee parasite Varroa destructor reduces hive vitality and honey yields by preventing growth of heathy bees and causes drastic loss in apiculture. Therefore, mite infestation in honey bee needs to be constantly controlled by beekeepers. To minimize this loss, a system called Var-Gor has been developed with the aim of controlling Varroa mite infestation before/just after entering the hive instead of the late period. Var-Gor is a hive entrance attachable device box consist of bee passage tunnels (width: 25 mm, height: 15 mm, and depth: 50 mm), autofocus detection camera combined with interface (process sensor: IV-HG10) and supportive image capturing equipment. Energy requirement of the device was provided by sustainable and eco-friendly solar panels and power batteries placed close to hives. Additionally, a Wi-Fi-like network connection and easy to use mobile application software was designed for the early warning of the beekeepers in case of Varroa destructor infestation. All the systems were designed compatible with cloud storage and 5G smart technology developments. Var-Gor was trained with 60% Varroa mite containing honey bees (Apis mellifera L.) and 40% not containing ones. The matching range of shapes to regular honey bee and Varroa mite was 70%. Following the training system, it was able to detect existing Varroa mites with the highest accuracy within the trained samples. Even though the system requires further training based on the location and color of the mite on bee, it is a promising smart technology device for early detection of the Varroa mites.

Vertical Drain Tube Attachment Device

Biomedical Safety & Standards: June 15, 2021 - Volume 51 - Issue 11 - p 85 doi: 10.1097/01.BMSAS.0000753772.75451.37

The ways to increase the durability of cutting tools (sintered carbide knives) in the production of steel fiber

One of the ways to increase the strength and reliability of building structures is the use of steel – fibre reinforced concrete. Steel – fibre reinforced concrete has significant advantages over conventional concrete. A high degree of resistance to cracking contributes to an increase in such physical and mechanical parameters as compressive, tensile and bending strength, water resistance, frost resistance, resistance to water and chemical penetration. In steel – fibre reinforced concrete, steel – fibre is used as a reinforcing material, evenly distributed over the volume of concrete.In the process of steel – fibre production, the fiber is cut with carbide knives. The article deals with the issues of increasing the wear resistance of carbide knives used for cutting steel – fibre, and suggests ways to increase the durability of cutting tools. The influence of the quality of tungsten-cobalt hard alloy on the wear resistance of knives is analyzed, and a knife attachment device is developed.