Lifting Technique Research Articles

Lifting techniques in bovine recumbency

In most cases, bovine recumbency (downer cow syndrome) is a complication of periparturient hypocalcemia, but may also be caused by other metabolic disorders, trauma, toxic mastitis or metritis. An important treatment measurement in the recumbent cattle is to bring the cow to its feet, in order to avoid quickly occurring secondary damage. Various lifting systems are on the market, such as a cow lift with a supporting harness or hip clamps. Such lifting systems are easy to use and relatively inexpensive. However, these techniques can cause secondary injuries and ischemic pressure damage. An alternative method is the use of a specially designed flotation tank. The buoyancy of the water gently lifts the cattle avoiding secondary, neuromuscular lesions. The success rate in the therapy of recumbent cattle can be significantly improved by the correct and early use of suitable lifting techniques. In this review, the most common lifting techniques for recumbent cattle are summarized.

Squat Lifting Imposes Higher Peak Joint and Muscle Loading Compared to Stoop Lifting

(1) Background: Yearly, more than 40% of the European employees suffer from work-related musculoskeletal disorders. Still, ergonomic guidelines defining optimal lifting techniques to decrease work-related musculoskeletal disorders (WMSDs) has not been unambiguously defined. Therefore, this study investigates if recommended squat lifting imposes lower musculoskeletal loading than stoop lifting while using a complex full body musculoskeletal OpenSim model. (2) Methods: Ten healthy participants lifted two different weights using both lifting techniques. 3D marker trajectories and ground reaction forces were used as input to calculate joint angles, moments and power using a full body musculoskeletal model with articulated lumbar spine. In addition, the muscle activity of nine different muscles was measured to investigate muscle effort when lifting. (3) Results: Peak moments and peak joint power in L5S1 were not different between the squat and the stoop, but higher peak moments and peak power in the hip, knee, elbow and shoulder were found during squat lifting. Moment impulses in L5S1 were higher during stoop lifting. This is reflected in higher peak electromyography (EMG) but lower muscle effort in prior described muscles during the squat. (4) Conclusions: Squat lifting imposes higher peak full body musculoskeletal loading but similar low back loading compared to stoop lifting, as reflected in peak moments, peak power, and peak EMG.

Modeling and adaptive control of modified LUO converter

This study presents the implementation and modeling of adaptive control of a modified LUO converter which eventually result in the progression of the dynamic functioning of power converter. In general, LUO converters include two series, which are major and additional series. DC-DC conversion has been executed to employing LUO converter and fly back converter. It uses VL technique in order that output voltage is intensified in every stage. The most important advantages of the proposed structure are that it has the benefits of the switched capacitor and as well VL technique. PI Controller has been used in order to simulate the experimental set-up. Embedded C programming was employed to create the PI controller set up. Kp and Ki values have been calculated using the Ziegler Nichols technique. Simulation has been done using MATLAB. Boosting has been accomplished using the voltage lifting technique. Findings emphasized that LUO converters are likely to improve the power transfer gain in energy progression. Also, the proposed LUO converter in the research has been proven to be able to provide a topology which eventually lessens the output ripple and losses. To verify the proposed DC-DC power converter performance, the simulation and experimental setup has been tested with certain parameters, including source voltage and current, capacitors, etc. Several forms of LUO converter voltage lifting (VL) methods performance including ultra-lift, re-lift and self-lift have been compared with that of the performance of the proposed design. Comparison between different voltage gains of LUO converter topologies have also been carried out in this research. The results reveal that the proposed design gives better boost in voltage, compared with that of the existing designs.

Reconstruction of the bridge using heavy lifting technique

In work the problem of use of Heavy Lifting technology («Rise of heavy constructions») for dismantling of the flying structure of the bridge at its reconstruction is considered. The questions of development and application vertically of drawbridges are raised. Contribution of foreign designers to development of adjustable flights. Experience of modern construction of bridges, using a method, for mounting of metal constructions of bridges is considered. The importance of short-term repair and reconstruction of bridge constructions as most important components of a transport network of the country is noted. Reconstruction of the bridge through the Tobol River on federal highway R-404 in the Tyumen region is briefly considered. Works of authors, about technology of safe use of lifting frames for rise and lowering of segments of steel concrete bridges and beams for a sliding of flying buildings from previously strained concrete. Foreign and domestic experience of use of Heavy Lifting technology for mounting and dismantling of bridge constructions is considered. On the example of works on dismantling of the flying building at reconstruction of the bridge through the Yuganskaya River of a channel on km 740,863 highways R-404 Tyumen-Tobolsk-Khanty-Mansiysk are shown to feature of works on this technology, the arising problems and ways of their solution. It is noted that use of Heavy Lifting technology allows carrying out reconstruction to the shortest possible time, having saved considerable resources.

Fusion estimation for multi-rate linear repetitive processes under weighted try-once-discard protocol

In this paper, the fusion estimation problem is studied for a class of discrete time-varying multi-rate linear repetitive processes (LRPs) under weighted try-once-discard protocol. The LRPs are measured by multiple sensors that are allowed to have different sampling periods, and the state updating period of the LRPs is also allowed to be different from the sampling periods of the asynchronous sensors. To facilitate the estimator design, the lifting technique is applied to transform the multi-rate LRPs to single-rate ones. Moreover, due to limited communication capability, the weighted try-once-discard protocol is adopted to schedule the asynchronous sensors. A set of local estimators is designed such that the upper bounds on the local estimation error covariances are guaranteed, and such upper bounds are then minimized by appropriately designing the estimator gains. Furthermore, the estimates from the local estimators are fused by recurring to the sequential covariance intersection fusion method. Finally, a simulation example is given to demonstrate the effectiveness of the proposed fusion estimation scheme.

Koopman-Based Lifting Techniques for Nonlinear Systems Identification

We develop a novel lifting technique for nonlinear system identification based on the framework of the Koopman operator. The key idea is to identify the linear (infinite dimensional) Koopman operator in the lifted space of observables, instead of identifying the nonlinear system in the state space, a process which results in a linear method for nonlinear systems identification. The proposed lifting technique is an indirect method that does not require to compute time derivatives and is therefore well-suited to low-sampling rate data sets. Considering different finite-dimensional subspaces to approximate and identify the Koopman operator, we propose two numerical schemes: a main method and a dual method. The main method is a parametric identification technique that can accurately reconstruct the vector field of a broad class of systems. The dual method provides estimates of the vector field at the data points and is well-suited to identify high-dimensional systems with small datasets. This paper describes the two methods, provides theoretical convergence results, and illustrates the lifting techniques with several examples.

Using visual aids to influence manual lifting techniques: acute effects of viewing static images on spine motion

Purpose. This study aimed to determine whether untrained observers alter their spine as directed via static images of different lifting techniques. Methods. Ten men and eight women, who had no lifting or visual observation training, performed box lifts. Following a self-selected lifting technique trial, participants performed four experimental lifting trials (in randomized order) wherein they were instructed to execute lifts in accordance with the techniques pictured. These techniques differed by the amount of knee, trunk and spine flexion modeled. Peak lumbar flexion angles and flexion/extension velocities were quantified, and then statistically analyzed via general linear models with two within-participant factors (condition = technique; phase = lift/lower). Results. Lumbar flexion angles and flexion/extension velocities differed between conditions (p < 0.001), although the effects depended on the combination of postural characteristics pictured. A main effect of phase was observed for peak lumbar flexion velocity only (p = 0.001). No condition × phase interaction effects were detected for any dependent variables (p > 0.050). Conclusions. Acute changes in lifting mechanics can be elicited via visual observation of pictured techniques. However, if using pictures to attenuate peak lumbar flexion displacements and velocities when lifting, auxiliary instruction may be needed to direct observers’ attention to the spine curvature displayed.

Upper Lip Rejuvenation by Myocutaneous Subnasal Lift Technique

Background: With aging, the upper lip gradually loses itsyouthful pout and slowly droops downwards.Aim: In this study, we present a modification to thesubnasal lip lifting technique to improve scar quality andaesthetic outcome.Patients and Methods: This study included twenty-threeadult female patients. Elliptical subnasal excision includingskin and muscle was done. Assessment criteria included scarquality, lip height, vermillion and incisor show. In some cases,objective measurements of the lip was used.Result: All patients had accepted hidden scar. Total lipheight and prolabium length were significantly decreased andvermilion height increased. One case had minimal change inthe vermilion show, improved with filler injection. Finally,all patients showed overall satisfactory outcome.Conclusion: A wedge excision form the superficial partof the orbicularis oris muscle with skin excision reducestension on the scar of subnasal upper lip lift. The excisiondoes not affect upper lip muscle function and it can improvethe aesthetic outcome and achieve a younger pleasant look.Larger patient population studies are needed to confirm thedata. Our proposed preliminary objective assessment methodis a very interesting method that can validate future results.Evidence based medicine: Level IV, case series.

A new linear and conservative finite difference scheme for the Gross–Pitaevskii equation with angular momentum rotation

A new linear and conservative finite difference scheme which preserves discrete mass and energy is developed for the two-dimensional Gross–Pitaevskii equation with angular momentum rotation. In addition to the energy estimate method and mathematical induction, we use the lifting technique as well as some well-known inequalities to establish the optimal \(H^{1}\)-error estimate for the proposed scheme with no restrictions on the grid ratio. Unlike the existing numerical solutions which are of second-order accuracy at the most, the convergence rate of the numerical solution is proved to be of order \(O(h^4+\tau^2)\) with time step \(\tau\) and mesh size \(h\). Numerical experiments have been carried out to show the efficiency and accuracy of our new method. doi:10.1017/S1446181119000026

Nasolabial suspension of the malar fat pad: a new, minimally invasive and reversible technique for facial symmetrization in permanent facial paralysis

Introduction: For the treatment of asymmetry of the midface due to permanent peripheral facial nerve palsy of different etiologies - which means a great psychical burden for the patients - several surgical solutions have been described. Aim: Our goal was to elaborate a minimally invasive surgical technique, that, on one hand, restores an adequate nasolabial fold, which is the most determinative keystone of facial symmetry. On the other hand, our technique can give an appropriate lift for the malar fat pad with shorter operative time and burden, with much lower complication rate and shorter recovery period compared to the classic static sling suspension techniques. Method: Out method is based on the formation of a neo-nasolabial fold, which is then suspended to the temporal fascia by permanent threads thus restoring facial symmetry and giving a lifting effect on the midfacial soft tissues as well. Results: Between 2014 and 2017, six patients had been operated with this nasolabial lifting technique of the malar fat pad without any major complications under local anesthesia on an outpatient basis at our Department. Conclusions: As our surgical exploration is minimal, the postoperative period is shorter, no visible scars remain on the face and the complication rate is negligible. If necessary, suspension could easily be adjusted, and as the technique is reversible, no other possible facial reconstruction methods are excluded. Our method can symmetrize the face in resting position completely on the long term, which is the most important issue for our patients according to their feedback. Orv Hetil. 2019; 160(22): 869-872.

Variance-constrained H∞ state estimation for time-varying multi-rate systems with redundant channels: The finite-horizon case

This paper deals with the H∞ state estimation problem for a class of networked multi-rate time-varying systems with estimation error variance constraint. The redundant channel transmission scheme is employed to reduce the packet dropout rate and improve the quality of the data delivery. By utilizing the lifting technique, an augmented estimation error system is established with a uniform sampling rate. The objective of this paper is to design a time-varying state estimator such that, in the simultaneous presence of the asynchronous sampling, probabilistic packet dropouts as well as stochastic noises, the error dynamics of the state estimation satisfies both the prescribed H∞ performance requirement and the prescribed estimation error variance constraints. Through intensive stochastic analysis, sufficient conditions are established to ensure the existence of the desired estimator whose parameters are determined by solving a set of recursive linear matrix inequalities. A numerical example is presented to show the validity of the proposed estimation strategy.

MANUAL MATERIAL HANDLING IN THE ‘KARUNG’ LIFTING PROCESS USING BIOMECHANIC AND PHYSIOLOGI APPROACH

This study was aimed at minimizing musculoskeletal disorder (MSDs) in heavers on traditional markets by completing facilities and improving lifting techniques that are in accordance with ergonomic aspects. This research was conducted in traditional markets with heaver objects which are often carried out in the process of moving goods. This study used biomechanics and physiology methods to be able to analyze body posture so that it can prevent spinal damage. The data were then analyzed using Maximum Permissible Limit (MPL), which previously carried out data collection on the size of the body posture. The analysis of the results was done to determine the value of the compression force (FC). FC values are the basis for comparison with Action Limit (AL). The results show that FC values = 10,018,078N, FC&gt; MPL. Importantly, the position of the heavers’ posture is at a dangerous level. Proposed improvements using a tool and after being developed again will result in changes in FC values to 3370.94, FC &lt;AL means the position of the body in a safe condition. The results of this study are expected to provide an assessment that helps prevent spinal damage.MANUAL MATERIAL HANDLING PADA PROSES PENGANGKATAN KARUNG MENGGUNAKAN PENDEKATAN BIOMEKANIKA DAN FISIOLOGI Penelitian ini bertujuan untuk meminimumkan keluhan Musculoskeletal disorder (MSDs) pada pekerja kuli panggul di pasar tradisional dengan merancang fasilitas dan memperbaiki teknik memindahkan barang yang sesuai dengan aspek ergonomis. Penelitian ini dilakukan di pasar tradisional dengan objek kuli panggul yang sering melakukan proses pemindahan barang. Penelitian ini menggunakan metode pendekatan biomekanika dan fisiologi untuk dapat menganalisis postur tubuh sehingga dapat mencegah cedera tulang belakang. Data kemudian dianalisa menggunakan Maximum Permissible Limit (MPL) yang sebelumnya dilakukan pengambilan data ukuran postur tubuh pekerja tersebut. Analisis hasil dari perhitungan dilakukan untuk mengetahui nilai dari force compresion (FC). Nilai FC menjadi dasar untuk dibandingkan dengan Action Limit (AL). Hasil dari analisa didapat nilai FC = 10.018,078N, FC&gt;MPL. Artinya, posisi postur tubuh pekerja dalam level berbahaya. Usulan perbaikan dengan menggunakan alat bantu dan setelah dianalisis kembali maka akan menghasilkan perubahan nilai FC menjadi 3370,94; FC&lt; AL artinya posisi tubuh dalam keadaan aman. Hasil penelitian ini diharapkan dapat memberikan rekomendasi alat bantu sehingga dapat mencegah cedera tulang belakang.

The effect of control strategies for an active back-support exoskeleton on spine loading and kinematics during lifting

With mechanical loading as the main risk factor for LBP, exoskeletons (EXO) are designed to reduce the load on the back by taking over part of the moment normally generated by back muscles. The present study investigated the effect of an active exoskeleton, controlled using three different control modes (INCLINATION, EMG & HYBRID), on spinal compression forces during lifting with various techniques.Ten healthy male subjects lifted a 15 kg box, with three lifting techniques (free, squat & stoop), each of which was performed four times, once without EXO and once each with the three different control modes. Using inverse dynamics, we calculated L5/S1 joint moments. Subsequently, we estimated spine forces using an EMG-assisted trunk model.Peak compression forces substantially decreased by 17.8% when wearing the EXO compared to NO EXO. However, this reduction was partly, by about one third, attributable to a reduction of 25% in peak lifting speed when wearing the EXO. While subtle differences in back load patterns were seen between the three control modes, no differences in peak compression forces were found. In part, this may be related to limitations in the torque generating capacity of the EXO. Therefore, with the current limitations of the motors it was impossible to determine which of the control modes was best. Despite these limitations, the EXO still reduced both peak and cumulative compression forces by about 18%.

Generalized Low-Rank Optimization for Topological Cooperation in Ultra-Dense Networks

Network densification is a natural way to support dense mobile applications under stringent requirements, such as ultra-low latency, ultra-high data rate, and massive connecting devices. Severe interference in ultra-dense networks poses a key bottleneck. Sharing channel state information (CSI) and messages across transmitters can potentially alleviate the interferences and improve the system performance. Most existing works on interference coordination require significant CSI signaling overhead and are impractical in the ultra-dense networks. This paper investigates the topological cooperation to manage interferences in message sharing based only on the network connectivity information. In particular, we propose a generalized low-rank optimization approach in a complex field to maximize the achievable degrees of freedom (DoFs) by establishing interference alignment conditions for the topological cooperation. To tackle the challenges of poor structure and non-convex rank function, we develop the Riemannian optimization algorithms to solve a sequence of complex fixed-rank subproblems through a rank growth strategy. By exploiting the non-compact Stiefel manifold formed by the set of complex full column rank matrices, we develop the Riemannian optimization algorithms to solve the complex fixed-rank optimization problem by applying the semidefinite lifting technique and the Burer–Monteiro factorization approach. The numerical results demonstrate the computational efficiency and higher DoFs achieved by the proposed algorithms.

Tracking of Periodic Trajectories for Switched Systems Under Time-Varying Asynchronous Switching

In this technical brief, we provide an asynchronous modified repetitive controller design to address the periodic trajectory tracking problem for switched systems with time-varying switching delays between plant modes and controllers. In the feedback channel, a dynamic output feedback mechanism is adopted. By utilizing the lifting technique, the dynamic output feedback-based switched repetitive control system is transformed into a continuous-discrete two-dimensional (2D) model to differentiate the control and learning actions involved in the repetitive controller. For the transformed 2D model, by constructing a piecewise Lyapunov functional and utilizing a matrix decomposition approach, sufficient conditions in terms of linear matrix inequalities (LMIs) and the average dwell time are developed to guarantee closed-loop exponential stability. The performance of the proposed approach is illustrated via a switched RLC series circuit example and numerical simulations are provided.

A NEW LINEAR AND CONSERVATIVE FINITE DIFFERENCE SCHEME FOR THE GROSS–PITAEVSKII EQUATION WITH ANGULAR MOMENTUM ROTATION

A new linear and conservative finite difference scheme which preserves discrete mass and energy is developed for the two-dimensional Gross–Pitaevskii equation with angular momentum rotation. In addition to the energy estimate method and mathematical induction, we use the lifting technique as well as some well-known inequalities to establish the optimal $H^{1}$ -error estimate for the proposed scheme with no restrictions on the grid ratio. Unlike the existing numerical solutions which are of second-order accuracy at the most, the convergence rate of the numerical solution is proved to be of order $O(h^{4}+\unicode[STIX]{x1D70F}^{2})$ with time step $\unicode[STIX]{x1D70F}$ and mesh size $h$ . Numerical experiments have been carried out to show the efficiency and accuracy of our new method.

Direct Brow Lift - An Update of Current Literature

Eyebrow ptosis is the earliest manifestation of the aging forehead. Surgical procedures to lift the ptotic brow were first published in the early 1900s and since the introduction of the direct brow lift technique, there have been numerous minor refinements to this procedure, as well as some major developments in surgical techniques. It was modified to utilize a mid-forehead or a coronal incision, and then superseded by the endoscopic technique of brow lifting. Yet, with the armory of brow lifting techniques that currently exist, there still is a major role for the direct brow lift, herein described in detail.

Evaluation and comparison of lift styles for an ideal lift among individuals with different levels of training

Training for safe lifting techniques is used by employers to lower their workers' exposure to risk of workplace injuries. To determine effectiveness of training, 266 attendees at two professional conferences were asked to identify and demonstrate their preferred lift technique with the demonstration being an ideal floor-to-waist height lift of a10-kg weighted crate. ‘Bend your knees’ was the most frequent preferred cue for each of the self-reported participant groups: untrained (n = 65), trained (n = 86), and trainers (n = 115) according to safe lifting techniques. The demonstrations showed that this cue was incorporated into the skill of lifting by all groups. Trained participants showed a stronger conformity for depth of squat; but, the overall variability suggested a lack of consensus on the ideal depth of squat. The trained group experienced less loading at L5/S1 (p = .021) compared to untrained that was countered by higher loading of the knee (p = .046). Trainers showed lower knee (p = .006) and shoulder (p = .03) loading with similar L5/S1 loading as the trained participants suggesting a broader set of criteria for safe lifting. While the study population was likely biased towards a common understanding of safe lifting techniques given the conferences were for ergonomists and safety professionals, the results provided valuable insight into potential knowledge gaps, and key messaging that is being delivered and integrated into one's knowledge; a program review of lift training is recommended.

Classification of Lifting Techniques for Application of A Robotic Hip Exoskeleton.

The number of exoskeletons providing load-lifting assistance has significantly increased over the last decade. In this field, to take full advantage of active exoskeletons and provide appropriate assistance to users, it is essential to develop control systems that are able to reliably recognize and classify the users’ movement when performing various lifting tasks. To this end, the movement-decoding algorithm should work robustly with different users and recognize different lifting techniques. Currently, there are no studies presenting methods to classify different lifting techniques in real time for applications with lumbar exoskeletons. We designed a real-time two-step algorithm for a portable hip exoskeleton that can detect the onset of the lifting movement and classify the technique used to accomplish the lift, using only the exoskeleton-embedded sensors. To evaluate the performance of the proposed algorithm, 15 healthy male subjects participated in two experimental sessions in which they were asked to perform lifting tasks using four different techniques (namely, squat lifting, stoop lifting, left-asymmetric lifting, and right-asymmetric lifting) while wearing an active hip exoskeleton. Five classes (the four lifting techniques plus the class “no lift”) were defined for the classification model, which is based on a set of rules (first step) and a pattern recognition algorithm (second step). Leave-one-subject-out cross-validation showed a recognition accuracy of 99.34 ± 0.85%, and the onset of the lift movement was detected within the first 121 to 166 ms of movement.

Simultaneous Sparse Recovery and Blind Demodulation

The task of finding a sparse signal decomposition in an overcomplete dictionary is made more complicated when the signal undergoes an unknown modulation (or convolution in the complementary Fourier domain). Such simultaneous sparse recovery and blind demodulation problems appear in many applications including medical imaging, super resolution, self-calibration, etc. In this paper, we consider a more general sparse recovery and blind demodulation problem in which each atom comprising the signal undergoes a distinct modulation process. Under the assumption that the modulating waveforms live in a known common subspace, we employ the lifting technique and recast this problem as the recovery of a column-wise sparse matrix from structured linear measurements. In this framework, we accomplish sparse recovery and blind demodulation simultaneously by minimizing the induced atomic norm, which in this problem corresponds to the block $\ell_1$ norm minimization. For perfect recovery in the noiseless case, we derive near optimal sample complexity bounds for Gaussian and random Fourier overcomplete dictionaries. We also provide bounds on recovering the column-wise sparse matrix in the noisy case. Numerical simulations illustrate and support our theoretical results.