Stress Control Technique Research Articles

A Review: Structural Shape and Stress Control Techniques and their Applications

AbstractThis review article presents prior studies on controlling shape and stress in flexible structures. The study offers a comprehensive survey of literature concerning the adjustment and regulation of shape, stress, or both in structures and emphasizes such control’s importance. The control of systems is classified into three primary classes: nodal movement control, axial force control, and controlling the two classes concurrently. Each class is thoroughly assessed, showcasing diverse methods anticipated by various scholars. Furthermore, the paper discusses methods to reduce the number of devices (actuators) to adjust and optimize actuators’ placement to achieve optimal structural control, considering the cost implications of numerous actuators. Additionally, various actuators are presented in detail, their advantages and disadvantages are also discussed. Moreover, the applications of the presented techniques are reviewed in detail, the essential recommendations for future work are also suggested.

Реализация принципов безопасности труда при подземной разработке сложноструктурных рудных месторождений

Most of the metal ores are mined from the rock deposits by technologies with natural control of the state of rock massifs. Rationalization of the methods for controlling the state of an ore-bearing massif, considering their geomechanics, is becoming a priority direction for improving technologies for the development of complex structure ore deposits. The purpose of the study is to substantiate the possibility of managing the state of massifs based on the combination of filling mixtures in the conditions of the Sadon ore belt deposit. The complex of studies includes the engineering division of the massif with the allocation of engineering structural sections. By modeling on equivalent materials, a mechanism for the development of stresses in the vicinity of a working was established. It is determined that the studied massif is discrete with a gravitational-tectonic-structural stress field. Based on the experimental data, a model of the intensity of the ore-bearing massif is built on the basis of the hypothesis of wedging of the rocks of the bearing layer. The role of expansion stresses and backfill strength in the input of the massif into the volumetric compression mode is determined. A stress control technique is proposed by dividing the massif into geomechanically safe areas. It was proven that backfilling systems ensure the recovery of reserves, improve the quality of ores and preserve the earth surface, protecting the region from the negative impact of mining. The complexity of exploitation of ore-bearing massifs determines the need to monitor the geomechanics of ore-bearing rocks. The combination of technologies is a real step in improving mining production, as it allows to reduce ore dilution, increase labor productivity, and also improve the safety conditions of workers by increasing the reliability of technology parameters.

Research on Optical and Mechanical Compatible Design Technology of Multilayer Films

The stress’s accumulation will critically affect optical device stability, leading to components’ deviation and film peeling. Stress control techniques based on strain cancelation cannot precisely match film stress, and it is difficult to reduce the total stress of multilayer film to ultra-low levels. Existing software for film system design is mainly based on 2D design concepts such as wavelength-spectrum and does not consider 3D design concepts such as wavelength-spectrum-stress, but the stress parameter plays an essential role in film performance, and it is necessary to use it as an optimization index for film design. In this paper, we introduce mechanical synchronization design into film system design. The multilayer film’s optimal structure is precisely matched by the genetic algorithm, and an ultra-low stress and wide-spectrum optical film element is developed under the dual requirements of optical performance and mechanical performance. This technique incorporates computer-aided design and automatically seeks an optimal combination of layered film nanostructures through self-compiled optical and mechanical compatible design software. While ensuring invariant optical properties, it can effectively reduce the total stress of multilayer film. This can provide a new idea for film stress control.

The Effectiveness of Mitigation Schemes on Electric Field Intensity (Stress Control) for Overhead Line Glass Insulator

This paper presents the simulation results of electric field distribution within suspension insulators on different stress control techniques under dry-clean and polluted conditions. Finite element method (FEM) is adopted to estimate the electric field behaviour along the insulator profile. For this study, COMSOL Multiphysics version 5.3a is used to perform the modelling and executing the field analysis. The effectiveness of zinc-oxide (ZnO) micro-varistor and grading ring as mitigation tools for the electric field intensity enhancement was examined in this study. The reference data from the dry-clean condition was used as the benchmark to examine the effect of pollution on electric field distribution on the insulator surface. It was found that the application of the combined techniques of ZnO micro-varistor and grading ring is the best scheme for stress control as it reduced the electric field intensity up to almost 84% for both dry-clean and polluted conditions. This study also found that the positioning the grading and corona ring is crucial as it will affect the electric field intensity distribution

Assignment-specific stress inoculation training for highlyspecialized IT personnel

As a result of their institutional assignments, highly specialized information technology (IT) personnel often find themselves in unpredictable and complex situations with a high level of difficulty. The complexity of the tasks to be carried out and the management of these tasks have set new challenges for this category of personnel. It is all the more important, therefore, that the personnel employed should acquire differentiated stress control techniques during qualifying training to develop a long-term performance capability. Following up on the earlier mentioned challenges, an assignment-specific stress inoculation training for highly specialized IT personnel is being introduced against the background of relevant stressors in the context of IT.

Assignment-Specific Stress Inoculation Training for Highly Specialized IT Personnel

As a result of their institutional assignments, highly specialized information technology (IT) personnel often find themselves in unpredictable and complex situations with a high level of difficulty. The complexity of the tasks to be carried out and the management of these tasks have set new challenges for this category of personnel. It is all the more important, therefore, that the personnel employed should acquire differentiated stress control techniques during qualifying training to develop a long-term performance capability. Following up on the earlier mentioned challenges, an assignment-specific stress inoculation training for highly specialized IT personnel is being introduced against the background of relevant stressors in the context of IT.

Lifestyle effects on telomeric shortening as a factor associated with biological aging: A systematic review

BACKGROUND: Telomeres are structures located at the chromosome ends, whose function is protecting DNA from attrition caused during cell division. Telomeric length serves as a mitotic clock, activating senescence and cellular cycle arrest when it reaches a shortening limit, which causes aging. Lifestyle is a factor that can affect telomeric shortening. Unhealthy habits have been linked to accelerated telomeric shortening, while healthy lifestyles are known to reduce this process and slow down aging. Current community has expressed an interest in improving lifestyle choices; however, an increase in unhealthy habits and chronic stressors have been seen. OBJECTIVE: This review aims to show the influence that different lifestyles have on telomeric length. METHODS: The review was carried out following the PRISMA statement in three databases. Twenty-eight research articles and nine review articles were reviewed, identifying six main lifestyles habits. RESULTS: Regular moderate-vigorous physical activity, dietary patterns rich in vegetables and antioxidants, and the stress control techniques were related to greater telomeric lengths and improvements in the oxidative response by reducing the levels of oxidative stress markers. On the contrary, stress, obesity, smoking, and alcoholism showed a negative effect of shorter telomeres, which can be a factor of early aging. CONCLUSION: The previous demonstrates the influences of lifestyles on telomere shortening rates and aging, therefore they should be considered as areas of interest for future research, and personal and community health improvement.

Relaxation to relieve muscle tension to the upper trapezius level in young adults

Introduction: The tightness and reduction in the flexibility have been reported to be associated with the occurrence of back pain in adolescents and adults [1]. Chronic mechanical neck pain can have a complex clinical presentation and is often difficult to treat [2]. In the clinical population, stretching is used to deal with numerous pathophysiological conditions such as various musculoskeletal disorders in order to provide relief from pain [3]. The purpose of this study was to determine which of these techniques, relaxation of muscle stretching and Laura Mitchell method, is more effective in decreasing the tension of the upper trapezius muscle in young adults. Materials and methods: Sixty young university students with pain and muscle tension in neck, mean age of 22.1 ± 3.8 years old and 79% female, were randomly distributed into three groups. The control group (G1) attended a lecture on stress control techniques, one of the experimental groups (G2) was submitted to Laura Mitchel relaxation method and, the other (G3) was submitted to stretching muscle techniques. The techniques were applied to the respective groups for a period of three weeks, three sessions per week, with 45 to 60 min per session. The variables, pain and muscle tension, were quantified by applying the scale of EVA and electromyography, respectively. was approved by Egas Moniz institutional board. All participants gave their informed consent. Results: At the end of 3 weeks there were only significant differences (p<0.05) on muscle tension measurements, with a decrease, within G3, accompanied by a significant decrease in pain intensity. In G1 and G2 were observed only small variations in pain intensity. Discussion and conclusions: This study revealed that stretching muscle techniques, to relieve upper trapezius muscular tension and pain in young adults, was more effective than Laura Mitchell relaxation technique.

Uticaj hroničnog stresa na zdravlje i mehanizmi prevazilaženja stresa

Stress represents a negative life experience, closely followed by physiological, cognitive, emotional, and behavioral changes that focus on changing the event or adapting to its effects. Any situation or occurrence that requires adaptation can be experienced as a stress, even positive situations and circumstances may be stressful, whether they come from the outside world, or the sources of stress is internal. While acute stress does not necessarily have a negative effect, if it lasts for a long time, or is frequently repeated, it becomes chronic, and can cause various serious disorders. During chronic stress, there is an exhaustion of the body's capacity for an adequate reaction, which can lead to long-lasting immunological dysfunction, which significantly impairs health and quality of life. According to the WHO (2017), stress is one of the causes of even 60% known diseases, and in a number of mental disorders a direct connection with stress has been reported: in acute stress reactions, "posttraumatic stress disorder", adjustment disorders and other reactions to severe stress. In addition, in all categories of mental disorders (ICD-10), the stressful situation or event plays a significant role in occurrence of the symptoms. A particular category of stress-related disorders are psychosomatic disorders. These are functional disorders in which there is no pathoanatomic substrate. In contrast to these, psychosomatic diseases are the type of illness in which there are structural changes of tissues and organs, the etiology of which is based on chronic stress, in addition to a number of other factors (Adamović, 1983) and which occur when there is a biological predisposition. The paper presents the mechanism of development of these diseases and some of the ways of coping with stress. According to the DSM-V, psychosomatic diseases are divided into skin diseases, gastrointestinal diseases, respiratory diseases, heart and blood vessel diseases, disorders of endocrine glands, rheumatoid diseases, gynecological diseases and others. In order to overcome stress and preserve health, psychological strategies for coping with stress play an important role. Multiple strategies are used, which include various stress control techniques: relaxation techniques, meditation methods, and assertive training, biofeedback and stress inoculation techniques. Successful mastering of coping stressful situations, constructive problem solving in life crisis, relaxation techniques and contributions to better adaptation to unexpected changes in life are of key importance for both mental and physical health.

Optical sensitivity non-uniformity analysis and optimization of a tilt optical readout focal plane array

An optical readout focal plane array (FPA) usually has a differently tilted reflector/absorber at the initial state due to the micromachining technique. The angular deviation of the reflector/absorber has a strong impact on the optical sensitivity non-uniformity, which is a key factor which affects the imaging uniformity. In this study, a theoretical analysis has been developed, and it is found that the stress matching in SiO2-Aluminum (Al) bilayer leg could make a contribution towards reducing the optical sensitivity non-uniformity. Ion implantation of phosphorus (P) has been utilized to control the stress in SiO2 film. By controlling the implantation energy and dose, the stress and stress stability are modified. The optical readout FPA has been successfully fabricated with the stress-control technique based on P+ implantation. It is demonstrated that the gray response non-uniformity of optical readout FPA has decreased from 25.69% to 10.7%.

Innovative technique for tailoring intrinsic stress in reactively sputtered piezoelectric aluminum nitride films

Novel technical and technological solutions enabling effective stress control in highly textured polycrystalline aluminum nitride (AlN) thin films deposited with ac (40kHz) reactive sputtering processes are discussed. Residual stress in the AlN films deposited by a dual cathode S-Gun magnetron is well controlled by varying Ar gas pressure, however, since deposition rate and film thickness uniformity depend on gas pressure too, an independent stress control technique has been developed. The technique is based on regulation of the flux of the charged particles from ac plasma discharge to the substrate. In the ac powered S-Gun, a special stress adjustment unit (SAU) is employed for reducing compressive stress in the film by means of redistribution of discharge current between electrodes of the S-Gun leading to controllable suppression of bombardment of the growing film. This technique is complementary to AlN deposition with rf substrate bias which increases ion bombardment and shifts stress in the compressive direction, if required. Using SAU and rf bias functions ensures tailoring intrinsic stress in piezoelectric AlN films for a particular application from high compressive −700MPa to high tensile +300MPa and allows the gas pressure to be adjusted independently to fine control the film uniformity. The AlN films deposited on Si substrates and Mo electrodes have strong (002) texture with full width at half maximum ranging from 2° for 200nm to 1° for 2000nm thick films.

Study on Critical, Modern Technology for Mining in Gassy Deep Mines

Abstract To achieve safe and highly efficient mining in the gassy, deep mines of the Huainan collieries simultaneous coal and gas extraction, and the corresponding ventilation methods were developed. This includes a set of mining procedures and principles which help insure safe and efficient production. Furthermore, green mining, meaning the comprehensive use of emitted gas, proper treatment of the environment and appropriate mine temperature control, is now standard. The concepts of modern mining and the principles of pressure relief are described. Coal-gas simultaneous extraction and multi-pressure relief techniques were developed which require a combination of surface and underground gas extraction. The application of Y-ventilation systems, of roadways retained along goafs, of stress control techniques for highly fragile mine roofs and of powerful, automatic and reliable mining equipment contributes to safe operation of modern deep mines. Operating parameters for these techniques are described and the results of their use discussed.

Mobility enhancement in local strain channel nMOSFETs by stacked a-Si/poly-Si gate and capping nitride

A local strained channel nMOSFET has been fabricated by a stress control technique utilizing a stacked a-Si/poly-Si gate and a SiN capping layer. It is found that the transconductance (G/sub M/) of nMOSFETs increases as the thickness of a-Si is increased. We also found that the G/sub M/ of devices with the SiN capping layer exhibits a 17% increase compared to that of its counterparts. The stacked gate a-Si/poly-Si with the capping layer can improve the G/sub M/ further to 29% more than the single-poly-Si gate structure without SiN capping layer.

Stencil Mask Technology for Electron-Beam Projection Lithography

The development of silicon stencil masks for cell projection lithography (CPL), electron projection lithography (EPL), low-energy electron-beam-proximity-projection lithography (LEEPL), and low-energy electron-beam lithography (LEB) is described. To satisfy the required pattern accuracy of the stencil masks, such as critical dimension and image placement, we developed a high-aspect stencil pattern formation technique to achieve a side-wall angle of over 90 deg and a membrane stress control technique using a stress-correction layer. In addition, for fabricating low-magnification stencil masks, we developed a new mask substrate with a sputtered scattering silicon membrane and a sputtered intermediate stopper layer as an etching stopper. We selected CrNx as the intermediate layer material, which demonstrated high performance in stencil mask fabrication. By improving the CrNx film qualities, its durability to dry and wet etching of backside silicon was improved. In order to improve the pattern image placement accuracy caused by membrane stress changes during stencil pattern formation, we developed a new and simple technique using a stress correction layer, which also functions as a silicon deep-etching mask. By using this functional layer, the total stress change in the pattern field in a mask pattern formation process was reduced to within 5 N/m, which corresponds to less than a 10 nm pattern image placement (IP) error.