Horizontal Joints Research Articles

The "elongate chelicera problem": A virtual approach in an extinct pterygotid sea scorpion from a 3D kinematic point of view.

Chelicerae, distinctive feeding appendages in chelicerates, such as spiders, scorpions, or horseshoe crabs, can be classified based on their orientation relative to the body axis simplified as either orthognathous (parallel) or labidognathous (inclined), exhibiting considerable diversity across various taxa. Among extinct chelicerates, sea scorpions belonging to the Pterygotidae represent the only chelicerates possessing markedly elongated chelicerae relative to body length. Despite various hypotheses regarding the potential ecological functions and feeding movements of these structures, no comprehensive 3D kinematic investigation has been conducted yet to test these ideas. In this study, we generated a comprehensive 3D model of the pterygotid Acutiramus, making the elongated right chelicera movable by equipping it with virtual joint axes for conducting Range of Motion analyses. Due to the absence in the fossil record of a clear indication of the chelicerae orientation and their potential lateral or ventral movements (vertical or horizontal insertion of joint axis 1), we explored the Range of Motion analyses under four distinct kinematic settings with two orientation modes (euthygnathous, klinogathous) analogous to the terminology of the terrestrial relatives. The most plausible kinematic setting involved euthygnathous chelicerae being folded ventrally over a horizontal joint axis. This configuration positioned the chelicera closest to the oral opening. Concerning the maximum excursion angle, our analysis revealed that the chela could open up to 70°, while it could be retracted against the basal element to a maximum of 145°. The maximum excursion in the proximal joint varied between 55° and 120° based on the insertion and orientation. Our findings underscore the utility of applying 3D kinematics to fossilized arthropods for addressing inquiries on functional ecology such as prey capture and handling, enabling insights into their possible behavioral patterns. Pterygotidae likely captured and processed their prey using the chelicerae, subsequently transporting it to the oral opening with the assistance of other prosomal appendages.

Investigation of Microstructure and Mechanical Properties of High-Depth-to-Width-Ratio Horizontal NG-GMAW Joint for S500Q Steel.

A novel high depth-to-width ratio of 15:1 narrow-gap gas metal arc welding technique was developed for the welding of S500Q steel in a horizontal butt joint. The bead arrangement of the I groove was optimized to produce a high-quality connection with the upper sidewall of the joint. The microstructure and mechanical properties were observed and evaluated by optical microscopy, scanning electron microscopy, tensile testing, and micro-hardness and impact toughness testing at 1/5, 2/5, 3/5, and 4/5 thickness of the joint. The 3/5 T position exhibited the highest strength, which was attributed to the presence of finer carbide precipitates. The highest micro-hardness appeared at 4/5 T. The highest impact toughness appeared at 3/5 T. The formation of coarse granular bainite was the major reason for the decrease in impact toughness in other regions. A microscopic fracture at 1/5 T and 3/5 T was further analyzed. It was observed that the width of the fibrous zone at 3/5 T was significantly larger than that at 1/5 T. The radial zones at 1/5 T were observed to exhibit cleavage, with secondary cracks on the fracture surface.

Experimental study on direct shear resistance of horizontal grouted joints in PC shear walls under compression and in-plane bending moment

The upper and lower panels of the prefabricated concrete shear wall are usually connected via horizontal grouted joints to maintain structural integrity. The horizontal grouted joints are typically under compression and in-plane bending moment. In the current design practice, it is generally considered that the direct shear resistance of the horizontal grouted joint is identical to that of the new-old concrete joint, and not affected by the bending moment if no bending failure occurs. In fact, as far as the authors know, both considerations lack experimental evidences. In this study, eight horizontal joint specimens were tested, including four grouted joints and four new-old concrete joints, to investigate their direct shear performances under constant compression and different in-plane eccentricities. Test results indicated that the ultimate direct shear resistance of the grouted joints was averagely 15.9 % lower than that of the new-old concrete joints. For the joints under small eccentricities associated with full shear plane in compression, the ultimate direct shear resistances remained unchanged compared to the cases under no eccentricity. However, for the grouted joints under large eccentricities associated with partial shear plane in tension, the ultimate direct shear resistances reduced up to 27.8 % compared to the grouted joint under no eccentricity. In addition, the shear transfer mechanism was investigated with the aid of the extended shear-friction model. Finally, recommendations were proposed for direct shear design of the horizontal grouted joints.

Strain energy dependent numerical simulation of rock fracture initiation and propagation using soundless cracking demolition agents (SCDA): Effects of SCDA-filled rock joints

Soundless Cracking Demolition Agents (SCDA) are gaining traction as an innovative technique for controlled rock fracturing in applications such as underground energy, mineral extraction, and excavation. This paper presents a novel numerical approach to simulate SCDA-charged rock fracture initiation using the strain energy density of SCDA. This approach eliminates the need for prior knowledge of the peak expansive pressure developed in a rock, a common requirement in conventional SCDA modelling. An empirically derived model is presented which captures the rate of energy release in SCDA as a function of applied strain to the surrounding material. The model was implemented in the 3-dimensional Distinct Element Code by applying an exponential strain-rate decay function. The proposed fracture stimulation method accurately mimics the expansion behaviour and finite strain energy release from SCDA expansion. The method was extended to simulate SCDA expansion in rock joints. The SCDA expansion method was assessed by creating a numerical model in which a central injection well was intersected by a horizontal joint and SCDA expansion was simulated in the injection well and the joint. The simulations were verified against laboratory fracture experiments. The model was extended to evaluate the fracturing performance of SCDA under varying joint roughness and confining pressures. SCDA expansion in rock joints introduces an additional compressive stress field that inhibits fracture initiation and propagation near the joint. Increasing fracture roughness suppressed fracture growth, but led to more fracture nucleation points around the injection well and shear damage at the joint interface. The simulation method employed shows sensitivity to confining pressures and simulates the fracturing potential of SCDA in different rocks subjected to confining pressures without requiring further calibration of the SCDA expansion parameters. The proposed numerical simulation method improves the accuracy in investigating the fracturing potential of expansive agents over existing simulation methods for SCDA.

Investigation on the influence of previous in-plane loading on the out-of-plane behavior of the innovative damped masonry infill wall

The damped masonry infill wall (DMIW) is an innovative masonry infill wall (MIW), wherein multiple horizontal subpanels, also called masonry units, are subdivided by inserting the horizontal damping layer joints (DLJs). While existing research on DMIW primarily focuses on its pure in-plane (IP) and pure out-of-plane (OOP) behavior, it is crucial to account for the interaction effect between IP and OOP behaviors to accurately assess OOP performance, Failure to consider this interaction may lead to an overestimation of OOP capacity, a concern previously highlighted in traditional MIW studies. Addressing this gap, this study conducts a sequential experiment involving IP cyclic quasi-static loading followed by OOP monotonic quasi-static loading. The aim is to examine the influence of previous IP cyclic loading on OOP behavior, considering factors such as OOP damage evolution, performance parameters, deformation patterns, and resistance mechanisms. The results show that, in DMIW, the effect of previous IP cyclic loading on the reduction of OOP performance is significantly lower compared to traditional MIW. Furthermore, the fundamental OOP resistance mechanism of DMIW remains unchanged under IP-OOP sequential loading. However, the OOP deformation pattern is altered due to the previous horizontal cracks developed in the masonry units under IP cyclic loading. Finally, a simple bi-linear equation is derived to quantify the effect of the previous IP cyclic loading on the primary OOP performance parameters of the DMIW.

Is it inevitable to have dynamic horizontal acromioclavicular joint instability with a single tightrope?

Background and purpose Literature showed that single Tightrope fixation in acromioclavicular joint (ACJ) dislocation cases does not secure horizontal joint stability. A positive clinical cross-body adduction test is a usual outcome finding. We hypothesized that some cases might have some degree of horizontal stability, which might be confirmed with ultrasound examination. Methods This clinical study was performed on 27 patients who underwent single Tightrope application in acute ACJ dislocation. Patients were divided into group A which had an arthroscopic technique, and group B which had an open technique augmented with trans-ACJ fixation using two k-wires for 6 weeks. A clinical examination of the operated shoulders was done, and the results were compared with the sound shoulder examination in the same patient at the last 24 months postoperative follow-up visit. Besides, the results of the cross-body adduction test were correlated with ultrasound findings at the same visit. Records, operative details, and postoperative radiography were reviewed to assess if any factors would diminish the dynamic horizontal stability of the ACJ. Body mass index (BMI) was calculated per case. Results Group A had 17 patients (three patients had grade III dislocations, and 14 patients had grade V dislocations). Group B had 10 patients (four patients had grade III dislocations, and six patients had grade V dislocations). The clinical cross-body adduction test gave gross positive results in 14 patients out of group A patients while it gave gross positive results in six patients out of group B patients. Group A patients with negative results were 3, while group B patients with negative results were 4. By ultrasound, differences in horizontal translation of the clavicle within the ACJ in resting and cross-arm positions were more obvious in all operated shoulders than in all sound shoulders. Conclusion The less the Rockwood grading, the more potential to secure more horizontal stability. An open approach also gives more horizontal stability. With increased BMI, horizontal instability is usually masked. So, some factors may diminish, or mask clinical dynamic horizontal instability, which can be confirmed or rolled out with ultrasound usage.

An In Vitro Study Demonstrating the Significance of Acromioclavicular Ligament Repair in Restoring Horizontal and Rotational Acromioclavicular Joint Stability.

The principle of joint reconstruction surgery is to try to recreate the native joint biomechanics and stability. With respect to acromioclavicular joint (ACJ) surgery, much focus to date has been on restoring the superoinferior stability. There is concern that persistent horizontal instability following ACJ reconstruction could lead to poorer patient outcomes; therefore, we evaluated whether acromioclavicular (AC) ligament repair offers improved horizontal stability in conjunction with ACJ reconstruction. A whole-body human cadaver was used. The ACJ was exposed and subjected to a constant 70N load on the lateral end of the clavicle to test the anteroposterior (AP), superoinferior (SI), and horizontal pivot angle (HPA) around the ACJ. The AC and coracoclavicular (CC) ligaments were subsequently divided, and the above three parameters were re-tested. Ligament augmentation and reconstruction system (Corin Group, Cirencester, UK), LockDown (LockDown Medical Limited, Redditch, UK), Endobutton (Smith and Nephew Inc.,London, UK), and Neoligament implant (Xiros Ltd., Leeds, UK) were used to reconstruct the CC ligaments and tested with and without AC repair. The native ACJ allowed an average 2.48 mm AP and 3.88 mm SI translation with a 27° HPA. All synthetic implants significantly improved the vertical stability of the ACJ but allowed up to a four-fold increase in AP translation. Coupled with ACJ repair, all the reconstructions were far superior, especially in restoring horizontal stability. The implants varied in their approach to fixation and concentrated primarily on the reconstruction of CC ligaments. Our study was able to demonstrate that AC repair significantly improves the stability of the construct and significantly reduces vertical and horizontal instability.

China’s Urban Waste Resource Management Systems: A Case of the Yangtze River Basin

ABSTRACT Urban waste management is vital for environmental protection and sustainable development. Understanding the characteristics and innovative paths of waste management systems in the Yangtze River Delta urban cluster is of significant importance. Analyzing 285 policies implemented from 2003 to 2022, the research employs methods like stage evolution text quantification and network structure analysis to reveal distinct characteristics of policy evolution in urban waste management. The study identifies a four-stage pattern of policy development: policy pilot stage, policy implementation stage, policy regulation stage, and policy dissemination stage. The findings highlight an increasing diversification of policy initiators and improvements in multisector collaboration. The central government plays a pivotal role in guiding urban waste management, while local governments follow suit through demonstration, indicating a preference for individual local autonomy over horizontal joint management.

Experimental investigation of the effect of horizontal construction joints on the behavior of deep beams

Abstract Construction joints serve as interruption points in the concrete placement process, which is necessary because it is often not feasible to pour concrete continuously in many structures. The quantity of concrete that can be poured at a single instance depends on the batching and mixing capacity, as well as the strength of the formwork. An effective construction joint must ensure sufficient flexural and shear continuity across the junction. Many studies investigated the construction joints in the reinforced concrete (RC) normal beams, but there are no studies investigating the effect of construction joints on the behavior of the RC deep beams. This study was prepared to show the behavior of deep beams having horizontal construction joints (HCJs) extended through their entire length. The parameter studied in this research was the location of the HCJ within the beam height. Four simply supported RC deep beams were tested under a two-point static load up to failure. One of these beams was without a construction joint and was considered a reference beam. Each one of the other beams has only one horizontal construction. The location of these joints was below, at, or above the beam mid-height. The crack patterns, the strain distributions, the mode of failure, deflection, and failure load are discussed. It was found that the existence of construction joints below, at, or above the beam mid-height results in a decrease in load failure load by 9, 11, and 1% compared with the reference beam. It can be concluded that the best location of the HCJ in the RC deep beam is in the upper part of the beam.

Optimized Design of Robotic Arm for Tomato Branch Pruning in Greenhouses

Aiming at the robotic pruning of tomatoes in greenhouses, a new PRRPR configuration robotic arm consisting of two prismatic (P) joints and three revolute (R) joints was designed to locate the end effector to handle randomly growing branches with an appropriate posture. In view of the various spatial posture of the branches, drawing on the skill of manual pruning operation, we propose a description method of the optimal operation posture of the pruning end effector, proposing a method of solving the inverse kinematics of the pruning arm based on the multi-objective optimization algorithm. According to the spatial distribution characteristics of the tomato branches along the main stem, the robotic arm structure is compact and the reachable space is maximized as the objective function, and a method of optimizing the key geometric parameters of the robotic arm is proposed. The optimal maximum length of the arm’s horizontal slide joint was determined to be 953.149 mm and the extension maximum length of its telescopic joint was 632.320 mm. The verification test of the optimal structural parameter showed that the optimized robotic arm could reach more than 89.94% of the branches in the pruning target area with a posture that meets the pruning requirements. This study is supposed to provide technical support for the development of a tomato pruning robot.

Experimental study on bond-slip behavior of vertical connecting rebar in the horizontal joints of double- superimposed shear wall

The horizontal joint of double-superimposed shear wall is the important part affecting the seismic performance of the wall. The horizontal joint mainly relies on the synergistic action between the vertical connecting rebar and the cast-in-place concrete to transfer the horizontal and vertical loadings and coordinate the deformation. Therefore, it is necessary to study the bond-slip behavior between the vertical connecting rebar and the cast-in-place concrete. In this paper, the effects of the cast-in-place layer thickness, the concrete strength, the anchorage length, and the diameter of rebar on the interface bond properties of vertical connecting rebar were analyzed through pullout tests. Based on the experimental results, the calculation formulas for bond strength and peak slip were proposed. According to the distribution of bond stress along the anchorage length, the bond-slip constitutive model optimized by the bond position function was established to describe the bond-slip behavior between the vertical connecting rebar and the cast-in-place concrete.

Bearing capacity of horizontal joints of UHPC prefabricated shear walls with vertical bars splicing by cold-extrusion sleeves

To study the shear performance of the horizontal joints of ultra-high-performance concrete (UHPC) prefabricated shear walls with vertical bars splicing by cold-extrusion sleeves, unidirectional loading tests for three samples have been conducted and a method to calculate the shear bearing capacity of the horizontal joint has been proposed. The influence of the reinforcement ratio and axial compression ratio on failure mode, cracking morphology, load-displacement curve, and shear bearing capacity of the horizontal joints has been analyzed in the tests. In addition, the failure process of the three samples has been simulated using finite element method. The results showed good agreement between the test results and numerical results, which certified the validity of the proposed calculation method for the shear capacity of the horizontal joint. The test results showed that the cold extrusion sleeve connection can effectively transmit the stress of the reinforcement, and the shear bearing capacity of the horizontal joints of the UHPC prefabricated shear wall can be enhanced by increasing the axial compression and reinforcement ratios.

Coracoclavicular and acromioclavicular ligament reconstruction with a double-bundle semitendinosus autograft and cortical buttons for chronic acromioclavicular joint dislocations: clinical and imaging outcomes

BackgroundThere are few clinical and radiographic studies of coracoclavicular (CC) ligament reconstruction in chronic acromioclavicular (AC) joint dislocation. Additionally, reported AC joint reduction rates vary. HypothesisArthroscopically assisted double-bundle semitendinosus tendon autografts with CC and AC ligament reconstruction for AC joint reconstruction provide AC joint stability and improved function at the final visit. MethodsIn this retrospective study of prospectively collected data, 21 patients surgically treated for chronic AC joint dislocation (Rockwood III–V) were assessed clinically and radiographically preoperatively, and at day 1, 3 months, 12 months, and at a final visit (> 24 months) postoperatively. Clinical assessments included Constant and ASES scores. The CC vertical distance (CCD) on the affected and unaffected sides [CCD ratio (%)] on the anterosuperior view were measured. AC joint vertical reduction loss was defined as an increase in the CCD ratio of > 25%. Horizontal AC joint instability was evaluated on axillary views. Pearsons’ correlation coefficients were generated to examine the relationships among postoperative clinical scores, CCD ratio, interval from injury to surgery, and age at the time of surgery. ResultsTwenty-one shoulders in 21 patients (mean age, 40.0 years at the time of surgery; 16 men, 5 women) were evaluated with a mean 31.7-month follow-up period. The mean Constant scores, ASES scores, and CCD ratios significantly improved from preoperatively to the final visit [57.4 ± 10.1, 49.1 ± 12.1, 101.6 ± 64.1 preoperatively; 89.6 ± 5.3, 96.5 ± 4.2, 9.9 ± 34.5 at the final visit, respectively (P < 0.001 for all)]. Vertical AC and horizontal AC joint instability were observed in four shoulders (19.0%) and in one shoulder (4.8%), respectively. However, there was no significant correlation between the increase in CCD and clinical scores at the final visit (Constant score; r = 0.179, P = .438: ASES score; r = -0.260, P = .256) or the interval from injury to surgery (r = 0.099, P = .669) or age at the time of surgery (r = 0.019, P = .935). No clinical complications were associated with clinical symptoms. ConclusionsPatients who underwent the index procedure achieved significant improvement in shoulder function without complications related clinical symptom after a mean follow-up interval of 31.7 months. In contrast, the rates of total ACJ instability in the vertical and horizontal planes were unsatisfactory but compatible with those in previous studies.

Seismic performance of precast concrete sandwich walls with bolt-steel plate connection

The bolt-steel plate connection stands as a dry connection method in precast structures characterized by its simplicity, high efficiency, ease of assembly and disassembly, and environmental protection. Five precast concrete sandwich walls (PCSWs) with glass fiber-reinforced polymer (GFRP) to connect the interior and exterior concrete wythes were designed and tested to investigate the seismic performance of such walls under cyclic loads. Ultra-high performance concrete (UHPC) was used to strengthen the bolt-steel plate connection joint. This study investigated the effect of the sandwich wall between the two bolt-steel plate connection joints, opening, and UHPC on the seismic performance of PCSWs. The findings revealed that the sandwich wall between the two bolt-steel plate connection joints, UHPC, and the interface between UHPC and ordinary concrete had a significant influence on the failure modes, including four failure modes: shear failure of bolt-steel plate connection joint, concrete crushing at the wall toe and through-crack of the shear oblique cracks and horizontal joint, shear failure at the interface between the solid and sandwich walls, and shear failure typified by a "Keyway" configuration. The use of UHPC to strengthen the bolt-steel plate connection area could significantly improve the load-bearing capacity and peak drift ratio. Whether the sandwich wall was used in the non-bolt-steel plate connection area in the horizontal joint zone had minimal influence on both the load-bearing capacity and peak drift ratio. For the walls without UHPC strengthening, the ultimate load and ultimate drift ratio could be increased by using the sandwich wall between the two bolt-steel plate connection areas, however, it was the opposite when UHPC strengthening was used. The paper also compared the sandwich walls with the solid walls, and the results showed that the sandwich wall with bolt-steel plate connections had good seismic performance.

Low-Cyclic Reversed Loading Tests on Full-Scale Precast Concrete Composite Wall Connected by Tooth Groove and Grouted Sleeve.

In this paper, a novel precast concrete composite wall connected by tooth groove and grouted sleeve was introduced, which is produced in factories by means of structure-insulation integrated prefabrication, and the prefabrication and assembly process were presented minutely. To verify the feasibility and reliability of this novel tooth groove and grouted sleeve connection method and explore the joint connection performance and the seismic performance of the precast concrete composite wall connected by tooth groove and grouted sleeve, low-cyclic reversed loading tests with an axial compressive ratio of 0.1 were performed on two full-scale precast concrete composite walls. Moreover, the failure mode, hysteretic curve, skeleton curve, stiffness degradation, displacement ductility, energy dissipation capacity, and reinforcement strain were comprehensively discussed. The research results showed that under the vertical axial load and low-cyclic reversed load, the distributed reinforcements in the wall panel only played a structural role, while the connecting reinforcements at horizontal joints can always effectively transfer stress without bond failure, and the tooth groove and grouted sleeve connection performance was reliable. In addition, the hysteretic curves of the precast concrete composite wall connected by tooth groove and grouted sleeve were full, showing good ductile deformation capacity and energy dissipation capacity. In general, the precast concrete composite wall connected by tooth groove and grouted sleeve not only possessed favorable seismic performance but also showed obvious advantages such as green energy saving, high assembly rate, and less on-site wet operation, which can be applied to practical engineering under reasonable design.

Coupling of horizontal joint and topography effects on seismic response of a single face slope

A concentration of building damage and slope failure near the slope crest has been observed during numerous earthquakes. Documented researches have shown that the combination of topography and geological structure (joint) significantly affects the seismic response of the slope. To investigate this issue, a series of numerical simulation analyses are performed for a slope containing horizontal joints by varying normalized joint stiffness (K), the ratio of normal stiffness to shear stiffness (kn/ks), joint spacing, the slope height, slope angle, and loading frequency. The acceleration amplification factor in the horizontal direction (AAF-X) in the slope distributes fluctuation characteristics when K is less than 1. The AAF-X at the slope crest increases with the increase of kn/ks. Meanwhile, the AAF-X at the slope crest increases first and then decreases with the increasing joint spacing. The AAF-X of jointed slope shows fluctuation change law along the slope surface with the increasing slope height while the AAF-X generally increases for homogeneous slope. The AAF-X at the slope crest of the jointed slope is amplified for different slope heights. A complex interaction exists between the topographic and joint effects on the seismic response of the slope and the two effects cannot be easily decoupled.

Numerical study on the design performance of wedge-type precast horizontal wall-slab joint for vertical load transfer

Construction of the residential buildings using large panel system (LPS) technology is an efficient and cost-effective way to provide housing to the populations at large scale. The main weakness of the system is the vertical load transfer at the joints. Horizontal wedge-type joints have known to perform well in load transfer from slab and the upper wall to the lower wall. However, limited research has focused on understanding the damage mechanism in the horizontal joints. This study is aimed at developing a finite element (FE) model of a horizontal wedge-type connection based on the experimental results. Parameters that affect the failure mechanism are transverse wall reinforcement, relative concrete strengths and slab bearing. These parameters were incorporated in the calibrated model to examine their effect on joint strength and damage progression. The results showed that the addition of transverse reinforcement improves the joint capacity and relative concrete strengths between joint and precast members influence the failure type. Furthermore, the comparison of simulation results with the existing design procedures showed that the design formulation, which is primarily focused on closed-type horizontal joints, shows good agreement with the simulation results and can therefore be used for the design of wedge-type joints.

Seismic performance test of bolted U-shaped steel assembled shear wall

A new type of assembled shear wall with energy dissipation and seismic damping function was proposed for the damage mechanism and weak points of typical assembled shear wall structures under strong earthquake effects. Using a combination of model tests and numerical simulations, four new assembled shear wall specimens with a scaling ratio of 1:1.54 and a shear-to-span ratio of 1.52 were designed and fabricated. The corresponding seismic performance tests were carried out. The effects of the number of bolts, axial compression ratio and longitudinal reinforcement ratio of edge members on the damage mode, hysteresis performance, bearing capacity, deformation performance, stiffness degradation and energy dissipation capacity of the specimens were systematically analyzed. The test results show that the damage mode of each specimen is basically the same as that of the common shear wall with the same shear-to-span ratio, which is bending-shear type damage However, the new assembled shear wall has more excellent hysteresis performance and energy dissipation capacity. Friction between the steel plates of the horizontal joints consumes a lot of energy and further inhibits wall damage. The energy dissipation value at the point of destruction of the wall is significantly higher than that of ordinary cast-in-place wall. The energy consumption value of the specimen PFSW is about 6 times that of a cast-in-place wall. When the number of bolts decreases, hysteresis performance decreases and wall deformation increases. The decrease of axial pressure ratio or longitudinal reinforcement ratio of edge members leads to the decrease of bearing capacity and increase of ultimate displacement of shear wall. Finally, the finite element model of the corresponding specimens was established by ABAQUS software. The simulation results were in good agreement with the test results, which indicated the correctness of the proposed model. And it can be applied to the analysis of new assembled shear walls.

Examination of a practical method to quantitatively evaluate the rolling over movement in a clinical setting.

[Purpose] We investigated the utility of wearable inertial and magnetic sensing modules for analyzing neck and trunk movements during the rolling over movement. [Participants and Methods] The participants were instructed to roll over from the supine to the side-lying position with three sensor units attached to their forehead, xiphoid process of the sternum, and abdomen. Experiments were conducted on two prescribed patterns: one emphasizing hip joint flexion and adduction, and the other focusing on scapular protraction and horizontal shoulder joint adduction in two healthy participants (one male and one female). The flexion and rotation angles of the neck and trunk were calculated using conventional spreadsheet software with data obtained from the sensors. The obtained values were compared for agreement with those derived from a three-dimensional (3D) motion analysis device. [Results] The cross-correlation coefficient for the flexion and rotation angles of the neck and trunk between the two measurement methods was approximately 0.85, and the root mean square (RMS) angle difference was approximately 5.0°. [Conclusion] Wearable inertial and magnetic sensors can be used to quantitatively evaluate neck and trunk movements during the rolling over movement.

Introduction and Related Research on Horizontal Joint Forms of Prefabricated Shear Walls

Introduction and Related Research on Horizontal Joint Forms of Prefabricated Shear Walls