Sleeve System Research Articles

Performance Assessment of Base Plate Connections with Anchor Rod Sleeves

This research presents findings from a study focused on evaluating the performance of exposed base plate connections featuring anchor rods under cyclic loading conditions. The study introduces an innovative sleeve system approach designed to enhance the ductility of column base connections. The inclusion of a steel sleeve with defined geometric characteristics between the base plate and the anchor rod washer modifies the load path within the connection, resulting in a more ductile response. The study utilizes a validated finite element (FE) model to analyze exposed base plate connections featuring different sleeve shapes, illustrating the concept behind this novel method. The innovative approach discussed in this research has the potential to significantly increase the rotational capacity of connections without compromising their inherent strength.

Fitting of Different Intraradicular Composite Posts to Oval Tooth Root Canals: A Preliminary Assessment.

The purpose of the present study was to perform a preliminary analysis of the fitting of different fiber-reinforced composite (GFRC) posts to tooth root canals and determine the resin cement layer thickness. The following GFRC posts were assessed: bundle posts (Rebilda GTTM, VOCO, Germany), sleeve system (SAPTM, Angelus Ind, Brazil), and accessory posts (ReforpinTM, Angelus, Brazil). Twenty-four freshly extracted mandibular single-rooted pre-molars were endodontically treated and divided into six groups, according to the type of GFRC post and resin cement (self-adhesive or conventional dual-cured). Then, specimens were cross-sectioned and inspected by optical microscopy regarding the cement layer thickness and presence of defects such as pores, voids, or fissures were assessed. Bundle and accessory posts revealed a regular distribution of resin cement with a lower number of voids than found with sleeve systems. The sleeve system posts showed poor fitting at the apical portion of the root canals. The type of resin cement did not affect the thickness of the interface, although both bundle and accessory posts allow a better distribution of resin cement and fibers. The present preliminary study reveals interesting insights on the fitting of bundle and accessory posts to root dentin and resin cement layer thickness in oval-shape root canals. The sleeve system posts showed adequate fitting only at the coronal portion of the canals.

Experimental study on joint’s seismic performance of a PCSW with thermal insulation elements

Precast coupled shear walls with thermal insulation elements (PCSW-T) are structurally and thermally efficient systems, which are deemed promising in precast structures. Nevertheless, the beam-wall joint may still function as a weak region during seismic events, which remains a fraught issue. In this paper, an innovative connection using double-section mechanical sleeve (DMS) systems was presented and investigated experimentally. Two monolithic and four PCSW-T joint specimens, evenly divided into two groups, were tested under reversed cyclic and pushover loadings, with beam shear-span ratios of 2.5 and 0.75, respectively. Experimental results revealed that the PCSW-T joints displayed similar damage modes to the monolithic ones under different shear-span ratios, while their seismic behaviors in terms of strength, deformation, stiffness, ductility, and energy dissipation were even better. Consequently, the PCSW-T structure can fulfill the design criterion of “equivalent to cast-in-place”.

Improvement of Mechanical Properties of Materials for Magnesium alloy Die-casting by Heated Sleeve Systems

Improvement of Mechanical Properties of Materials for Magnesium alloy Die-casting by Heated Sleeve Systems

Rotational capacity of exposed base plate connections with various configurations of anchor rod sleeves

This paper presents a new approach that can enhance the rotational capacity of exposed base plate connections without degrading the initial stiffness or strength of the standard configuration. By inserting a steel sleeve with a designated geometry between the base plate and the anchor rod washer, the load path between the end plate and the rod can be interrupted, promoting a more ductile response. Exposed base plate connections with various sleeve geometries are numerically investigated using a validated FE model to demonstrate the concept of the proposed method. It was concluded that the proposed sleeve system substantially enhances the rotational capacity of the exposed column bases. An elastic response consistent with standard base plate connections is maintained indicating that the proposed system is compatible with existing codified elastic design approaches without modification.

Influence of New Sleeve Composite on Fracture Behavior of Anterior Teeth with Flared Root Canals.

We evaluated the fracture strength and failure mode of non-ferrule teeth with flared root canals that were restored using new experimental sleeve composites. Fifty endodontically treated anterior teeth with flared root canals were restored with direct restorations utilizing different techniques. Group A had teeth (non-ferrule) restored using commercialized MI glass fiber post + Gradia Core as core build-up. Group B had teeth (non-ferrule) restored with commercialized i-TFC glass fiber post + sleeve system. In Group C, the teeth (non-ferrule) were restored with an experimental sleeve composite with commercialized MI glass fiber post and Gradia Core. Group D, teeth (non-ferrule), were restored using custom-made tapered E-glass filling post and Gradia Core. Group E, teeth (with ferrule), were restored with commercialized MI glass fiber post + Gradia Core. After core construction, all specimens underwent direct composite crown restoration and were loaded until fracture using a universal testing machine. Average fracture loads were compared, and the failure modes were observed. Group C exhibited significantly greater fracture strength than other groups (p < 0.05). Favorable fracture teeth ratio of group C was more than that of the other groups. Thus, the new experimental sleeve composite could be clinically useful for core construction of non-ferrule teeth.

Smart Steering Sleeve (S3): A Non-Intrusive and Integrative Sensing Platform for Driver Physiological Monitoring.

Driving is a ubiquitous activity that requires both motor skills and cognitive focus. These aspects become more problematic for some seniors, who have underlining medical conditions and tend to lose some of these capabilities. Therefore, driving can be used as a controlled environment for the frequent, non-intrusive monitoring of bio-physical and cognitive status within drivers. Such information can then be utilized for enhanced assistive vehicle controls and/or driver health monitoring. In this paper, we present a novel multi-modal smart steering sleeve (S) system with an integrated sensing platform that can non-intrusively and continuously measure a driver’s physiological signals, including electrodermal activity (EDA), electromyography (EMG), and hand pressure. The sensor suite was developed by combining low-cost interdigitated electrodes with a piezoresistive force sensor on a single, flexible polymer substrate. Comprehensive characterizations on the sensing modalities were performed with promising results demonstrated. The sweat-sensing unit (SSU) for EDA monitoring works under a 100 Hz alternative current (AC) source. The EMG signal acquired by the EMG-sensing unit (EMGSU) was amplified to within 5 V. The force-sensing unit (FSU) for hand pressure detection has a range of 25 N. This flexible sensor was mounted on an off-the-shelf steering wheel sleeve, making it an add-on system that can be installed on any existing vehicles for convenient and wide-coverage driver monitoring. A cloud-based communication scheme was developed for the ease of data collection and analysis. Sensing platform development, performance, and limitations, as well as other potential applications, are discussed in detail in this paper.

Influence of the macrodesign of an implant and the sleeve system on the accuracy of template-guided implant placement: A prospective clinical study

Statement of problemThree-dimensional (3D) implant planning facilitates determining the optimal position and number of implants, in terms of function and esthetics, by taking into account adjacent structures. Template-guided implant placement is an established procedure for implementing this planning, although the accuracy between the planned and the actual implant position is subject to many influences. The influences of the macrodesign of the implants and the sleeve materials used have rarely been investigated clinically. PurposeThe purpose of this prospective clinical study was to investigate the accuracy of template-guided implant placement according to the macrodesign of different implants and the design of the drill sleeve. Material and methodsImplants were placed in 60 participants within 3 groups (n=20): tapered implant with a metal sleeve (T-MS), tapered implant with a polymeric sleeve (T-PS), and progressive tapered implant with a polymeric sleeve (XT-PS). After overlaying the 3D implant planning image with the postoperative intraoral scan, deviations were 2-dimensionally related to the implant shoulder (S) and the apex (A) in terms of height (2DHS/2DHA), mesiodistal (2DSmd/2DAmd) and buccolingual (2DSbo/2DAbo), as well as 3-dimensionally on the implant shoulder (3DS), on the apex (3DA), and on the axis deviation (Axis).The groups were compared by using the analysis of variance. The Tukey post hoc test was performed for normally distributed data to identify significant differences among groups (α=.05). ResultsThe errors for 2DSmd and 2DSbo were 0.26 to 0.40 mm across all groups. The 3DS group varied between 0.67 and 0.87 mm. No significant differences were found in terms of the material of the sleeves or the macrodesign of the implants (P>.05). Significant differences were found for 2DHS (P=.029) and 2DHA (P=.016) between the groups with the different sleeves. Group T-PS showed the least height deviation. ConclusionsIn terms of height deviation, significant differences were found among the groups, with deviations depending on the implant type and the sleeve type. Overall, the method showed a high level of accuracy, providing good predictability of the prosthetic rehabilitation.

Physical modeling of deformation of a steel bushing under axial compression of an elastic-plastic vibration-damping element of a milling mandrel

To reduce vibrations when milling thin-walled steel sleeves, compression is applied from the inside by uniformly distributed forces created by axial compression of an elastoplastic element made of polyurethane or rubber. It was hypothesized that the pressure at the point of application of the axial compressive force of the elastoplastic element will be higher than at the opposite end, which will lead to uneven elastic deformations of the fixed sleeve and, accordingly, to additional processing errors. When the base-push bush is pressed, the initial force builds up pressure in the first ring. In this case, the initial length of the set of washers will be reduced to a value at which the washers begin to deform and reach contact with the steel sleeve. Then, when you try to move the first ring virtually, the force of its pressing on the second will decrease by the friction force between the first ring and the steel sleeve. The theoretical dependences of the pressure distribution between sequentially located compressible elastoplastic elements are derived as functions of the friction coefficient and geometric parameters of the vibration damping sleeve system. The calculation examples show that in cases where rubber or polypropylene inserts are used as elastoplastic elements, the pressure already on the first element should be completely, and even in excess, blocked by the friction force of the elastoplastic element on the steel sleeve. To resolve this contradiction, physical modeling of the process under study was carried out. 3 rubber washers were inserted inside the steel sleeve. The set of washers was acted upon by two plungers extending into the sleeve by 2 mm. Experimental data show that the central part of the sleeve is most susceptible to deformations, the diameters of the ends also increase, but to a much lesser extent, and approximately the same, which refutes the hypothesis of uneven distribution of pressure and deformation along the length of the sleeve.The reported study was conducted under fi nancial support of RFBR within the framework of the scientific and research project &laquo;Postgraduates&rdquo; No. 20-38-90248.

A new idea to improve the cyclic performance of end plate beam–column connections

This paper presents a new idea to improve ductility and energy dissipation of seismic beam–column end plate connections by improving the contribution of the bolts to the rotation capacity. The load path in the connection is interrupted by inserting a steel sleeve, with a designated wall curvature, between the washer and the end plate, promoting a more ductile response, particularly when the sleeve is the weakest element in the load path. An analytical solution is firstly proposed to define the sleeve parameters that satisfy the sleeve fails before the failure of any other connection components. Subsequently, the cyclic performance of the end plate connection with various sleeve parameters is investigated through validated FE models. Results showed that the ductility and energy dissipation of the proposed sleeved connection are 2.86 and 3.88 times that of the standard configuration, respectively. Furthermore, the elastic response is consistent with the standard configuration indicating that the proposed sleeve system is compatible with existing codified elastic design approaches without modification.

Sleeve for Knee Angle Monitoring: An IMU-POF Sensor Fusion System.

The knee flexion-extension angle is an important variable to be monitored in various clinical scenarios, for example, during physical rehabilitation assessment. The purpose of this work is to develop and validate a sensor fusion system based on a knee sleeve for monitoring of physical therapy. The system consists of merging data from two inertial measurement units (IMUs) and an intensity-variation based Polymer Optical Fiber (POF) curvature sensor using a quaternion-based Multiplicative Extended Kalman Filter (MEKF). The proposed data fusion method is magnetometer-free and deals with sensors' uncertainties through reliability intervals defined during gait. Walking trials were performed by twelve healthy participants using our knee sleeve system and results were validated against a gold standard motion capture system. Additionally, a comparison with other three knee angle estimation methods, which are exclusively based on IMUs, was carried out. The proposed system presented better performance (mean RMSE 3.3 °, LFM coefficients, a1 = 0.99 ± 0.04, a0 = 0.70 ± 2.29, R2 = 0.98 ± 0.01 and ρC 0.99) when compared to the other evaluated methods. Experimental results demonstrate the usability and feasibility of our system to estimate knee motion with high accuracy, repeatability, and reproducibility. This wearable system may be suitable for motion assessment in rehabilitation labs in future studies.

Thermomechanical Modeling of a Sleeve Rehabilitation System for Pressure Pipes

Abstract The thermomechanical modeling of a sleeve rehabilitation system for pressure pipes is studied including temperature effect on system behavior. The rehabilitation system consists of a multicylinder axisymmetric layer system, with an intermediate layer of epoxy resins and two outer steel covers that are longitudinally welded forming a sleeve. The analysis is conducted over several stages; initially, the incidence of temperature on the rigidity of three types of resins currently available on the market is experimentally evaluated. Then, nonlinear relationships between rigidity and temperature are established from the evaluation of the resins, which are typical of an inhomogeneous material. The resins exhibit a significant loss of rigidity with temperature, generating a risk of delamination that could drastically reduce the effectiveness of the rehabilitation system in the event of possible temperature rises. An analytical model was developed to calculate contact pressures between the resin layer and the external sleeve, internal pipeline displacements, stresses, and deformations. Finally, contour plots were developed for different temperature, pressure levels, and pipe thickness as a graphics tool to predict pipeline failure due to plastic deformation or rupture.

A comparison of the use of a suprapatellar Chinese Aircraft-shaped Sleeve System versus suprapatellar intramedullary nailing for tibial shaft fractures: Outcomes over a one-year follow-up

IntroductionThis study aimed to investigate the effectiveness and safety of the Chinese Aircraft-shaped Sleeve (CASS) system on the clinical outcomes of tibial intermedullary nailing using a suprapatellar approach for the treatment of tibial fractures in a cohort of adult Chinese patients over a minimum one-year follow-up. MethodsAfter institutional review board approval, skeletally mature patients with Orthopaedic Trauma Association (OTA) type 42 tibial shaft fractures were randomized into either a SP approach using CASS group or a conventional SP approach group after informed consent was obtained. The operations were performed by a single senior orthopaedic surgeon according to group assignments. A group of 33 patients were treated using the CASS system and the other group of 34 patients were treated using a conventional SP approach. Both groups fully complied with research requirements and completed 12 months of follow-up. Magnetic resonance images (MRI) were obtained for the evaluation of the patellofemoral joint (PFJ) and residual debris preoperatively, as well as one week and 12 months postoperatively. Radiographs were used to assess alignment and union, visual analog scores (VAS) were used to assess anterior knee pain, and range of motion (ROM) and the Lysholm knee scoring scales were used for evaluating the operated knee at the 12-month follow-up. ResultsDifferences in cartilage lesion changes observed by MRI between the two groups were statistically significant (P = 0.030 at 1 week postoperatively; P = 0.025 at 12 months postoperatively). No significant differences were evident with respect to debris residue, malalignments, nonunion, VAS, ROM and Lysholm knee scoring scale with the exception of stair climbing (P = 0.02). ConclusionBased on the data of this one-year clinical follow-up study, the SP approach using the CASS system offers the potential to benefit patients suffering from tibial shaft fractures, who will be treated with intramedullary nailing especially for smaller patients.

Experience of application of multistage hydraulic fracturing technology in a cased vertical well

This article presents the results of the first multi-stage hydraulic fracturing in a vertical well at a field in the Aktobe region. The field has been developed from the very beginning as one development object. The total height of the deposits in some places reaches 400 m; accordingly, since the start of development, all productive formations were perforated through without segregation. Field trial carried out on a well with perforation with a total thickness of 182 m revealed 4 productive formations. In order to open all productive layers with fractures and involve them in the development, it was decided to use a 4 stage layout with a hydraulic fracturing sleeve system with a repeated opening / closing cycle. As a result, after multi-stage hydraulic fracturing using this technology, a 4-fold increase in oil production was obtained. In the future, it is planned to apply this method to other candidate wells.

Heating canarian greenhouse with a passive solar water–sleeve system: Effect on microclimate and tomato crop yield

Heating greenhouses is indispensable for plant development particularly in winter when air temperature is lower. In that sense, passive solar heating is a promising alternative compared to classic methods such as fossil fuels that are cost impacted and harmful to the environment.The current work is devoted to the study of the effect of a solar heating system using black plastic sleeves filled with water on the microclimate, tomato yield and the dynamic population of the tomato key pest, Tuta absoluta (Lepidoptera: Gelechiidae) in canarian greenhouses.The results show that the use of this heating system, improves the nighttime temperature inside the greenhouse by 3.1 °C and reduce by 10% the relative humidity compared to the control greenhouse. This microclimate improvement has a positive impact on the tomato production. It has increased by 35% compared to the control greenhouse. It was also noted that the presence of this heating system lead to a decrease in the development the population of T. absoluta in the heated greenhouse.Based on these results, the solar passive water–sleeve heating system can be an eco-friendly tool to prevent intensive use of fuel fossil and negative effect on the environment.

Application of the Chinese Aircraft-shaped Sleeve system in the treatment of tibial shaft fractures using a suprapatellar approach for tibial intramedullary nailing: a randomised controlled trial

BackgroundThe use of the suprapatellar approach for intramedullary nailing has recently become popular for the treatment of tibial fractures. This study aimed to investigate the effectiveness of using the Chinese Aircraft-shaped Sleeve (CASS) system on the clinical outcomes of tibial intermedullary nailing using a suprapatellar approach for the treatment of tibial fractures in a cohort of adult Chinese patients.MethodsMagnetic resonance images (MRI) of the knee joints of 212 healthy adults with normal lower limb function from May 2011 to May 2015 were obtained from a level I Chinese regional trauma centre. Sixty inpatients at the same trauma centre who underwent treatment for tibial shaft fractures from June 2015 to June 2018 were enrolled. Tibial intramedullary nailing fixation of tibial shaft fractures via the suprapatellar approach was performed with either a CASS system or a conventional sleeve. The measurements of patellofemoral joint anatomy, the surgical time, the assessments of the patellofemoral joint cartilage conditions, and information of residual debris based on arthroscopic analysis were subsequently collected.ResultsThe mean patellar angle (PA), sulcus angle (SA), sulcus width (SW) and sulcus depth (SD) were 135.40 ± 6.20°, 142.37 ± 5.33°, 33.37 ± 2.73 mm, and 4.29 ± 0.63 mm, respectively. The surgical time until entry reaming commencement and the irrigation time were significantly lower in the CASS group (P < 0.001). The difference in cartilage damage rate between groups was statistically significant (P = 0.031); the difference in residual debris conditions was not statistically significant (P = 0.1967).ConclusionThe use of the CASS system could improve clinical outcomes of intramedullary nailing via suprapatellar approach for patients with a small patellofemoral joint space.

Design of RFID-based sliding sleeve control system

Design of RFID-based sliding sleeve control system

Andrews bridge revisited: A new custom cast ribbed bar and sleeve design fixed removable partial denture

The loss of teeth invariably is followed by the loss of soft tissue. There is a high incidence (91%) of residual ridge deformity following anterior tooth loss reported in literature; the majority of these are Class III defects that require soft-tissue surgery to augment the ridge defects. Esthetic surgical replacement is difficult and unpredictable, particularly when papilla in the esthetic zone needs to be restored. One choice is a fixed removable prosthesis retained by an Andrews bar and sleeve system. The prosthesis is designed to meet the requirements for esthetics, comfort, phonetics, hygiene, and favorable stress distribution to the abutment and soft tissues. One of the major advantages of an Andrews's bridge over fixed prosthesis is that it can be removed by the patient for improved oral hygiene access. This article describes the procedure for fabricating a new custom cast “ribbed” bar and sleeve design Andrews bridge.

Mechanical and thermal properties of glass fiber–vinyl ester resin composite for pipeline repair exposed to hot-wet conditioning

Fiber-reinforced composites are a well-recognized option for repair and rehabilitation of the pipelines for the oil and gas industry. Infilled composite sleeve system provides an effective rehabilitation solution, where the sleeve acts as prime reinforcement without any direct contact with steel. However, the long-term performance of the repair is dependent, in part, on the effect of hygrothermal ageing of the composites. In this publication, glass transition temperature and mechanical properties are compared for glass-fiber reinforced vinyl ester composite, both as-manufactured and after hot-wet conditioning at 80℃. The tensile and shear strength reduced substantially during conditioning, whilst the elastic modulus was relatively stable. The average glass transition temperature of the composite dropped from the as-manufactured value of 110℃ to 97℃ and 101℃, after 1000 and 3000 h of conditioning, respectively, indicating that it is stable and that the composite is suitable for use as a pipeline repair material operating at 80℃. The results indicate that a 1000 h conditioning period, specified as a minimum period in ISO/TS 24817 is suitable for representing long-term properties for stiffness-based designs for the composite material and conditioning temperature investigated.

TU‐H‐BRA‐08: The Design and Characteristics of a Novel Compact Linac‐Based MRI Guided Radiation Therapy (MR‐IGRT) System

Purpose:To describe the design and characteristics of a novel linac‐based MRI guided radiation therapy system that addresses RF and magnetic field interference and that can be housed in conventional radiotherapy vaults.Methods:The MR‐IGRT system will provide simultaneous MR imaging combined with both simple (3D) and complex (IMRT, SBRT, SRS) techniques. The system is a combination of a) double‐donut split solenoidal superconducting 0.345T MRI; and b) a 90 cm isocenter ring‐gantry mounted 6MV, flattening filter‐free linac coupled with a stacked doubly‐focused multileaf collimator with 4 mm resolution. A novel RF shielding and absorption technology was developed to isolate the beam generating RF emissions from the MR, while a novel magnetic shielding sleeve system was developed to place the magnetic field‐sensitive components in low‐magnetic field regions. The system design produces high spatial resolution radiation beams with state‐of‐the art radiation dose characteristics and simultaneous MR imaging.Results:Prototype testing with a spectrum analyzer has demonstrated complete elimination of linac RF inside the treatment room. The magnetic field inside of the magnetic shielding was well below the specification, allowing the linear accelerator to operate normally. A novel on‐gantry shimming system maintained &lt; 25 ppm magnetic field homogeneity over a 45 cm spherical field of view for all gantry angles.Conclusion:The system design demonstrates the feasibility coupling a state‐of‐the art linac system with a 0.345T MRI, enabling highly conformal radiation therapy with simultaneous MR image guidance.S. Mutic's employer (Washington University) has grant with ViewRay; D. Low is former ViewRay scientific advisory board member (ended October 2015); T. Chmielewski, G. Fought, M. Hernandez, I. Kawrakow, A. Sharma, S. Shvartsman, J. Dempsey are employees of ViewRay with stock options (Dempsey has leadership role and Dempsey/Kawrakow have stock).