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1 – 10 of 80Zhen Yan Yu and Shan Cong
The few previous researches on the impact of calf compression garments (CG) on running performance while assessing physiological and perceptual factors. Therefore, this study…
Abstract
Purpose
The few previous researches on the impact of calf compression garments (CG) on running performance while assessing physiological and perceptual factors. Therefore, this study investigated how the clothing pressure of two types of Calf CG, CG1 and CG2, affects muscle fatigue and activation during running.
Design/methodology/approach
Five healthy amateur runners(three female and two male)were recruited for a 30-min running trial. They wear a Calf CG on their right leg (CG group), but not on their left leg(CON group). After obtaining the clothing pressure of Calf CG on the gastrocnemius lateral head (GL), gastrocnemius medial head (GM) and tibialis anterior(TA) of the right leg, surface electromyography (sEMG)of four muscles of GL, GM, TA and rectus femoris (RF) of the left and right legs were measured during running, and heart rate, cardiopulmonary rate, and human RPE were also measured. Blood bleed oxygen before and after the running trial were measured. The root mean square (RMS) of the characteristic values was selected as an index for the analysis of sEMG signals, and the data were analyzed using statistical and computational methods.
Findings
The results showed that the indexes of heart rate, blood oxygen, and RPE were significantly increased, indicating that the subjects had reached the fatigue level. The comparison of mean clothing pressure at GL, GM and TA locations reveals that the TA location consistently exhibits the highest pressure for both types of CG. When wearing CG1, the mean clothing pressure at the GL and GM test points is greater than that of CG2(CG1-GL = 0.2059 kPa > CG2-GL = 0.148 kPa; CG1-GM = 0.1633 kPa > CG2-GM = 0.127 kPa). This is attributed to the double-layered fabric on the sides of CG1, which precisely covers the GL and GM areas, thereby resulting in higher mean clothing pressure at these locations compared to CG2. Conversely, the mean clothing pressure at the TA location for CG1 is lower than that for CG2(CG1-TA = 0.3852 kPa < CG2-TA = 0.426 kPa). The pressure exerted by the CG1 on the lower limb test areas has both positive and negative effects, though neither are statistically significant. The pressure exerted by CG2 alleviates fatigue at the directly affected locations GL and GM, but exerts excessive pressure on TA, resulting in a negative effect. Additionally, CG2 pressure alleviates fatigue at the indirectly affected location RF on the same side. Based on the specific clothing pressure data, it is concluded that when the pressure at the GM location is 0.127 kPa, 30 min of running has a fatigue-relieving effect. However, the pressure should not be excessively high, at 0.1633 kPa it exhibits an insignificant adverse effect. At the TA location, a garment pressure mean between 0.3852 and 0.426 kPa does not alleviate fatigue after 30 min of running, and the negative effect becomes more pronounced as the pressure increases. The pressure exerted by the CG at GL, GM, TA and RF locations shows significant changes from the previous time period during the 15–18 min interval after running. Therefore, in the design of CG, attention should be paid to the changes in clothing pressure effects on muscles during this specific time period.
Originality/value
The few previous researches on the impact of calf compression garments (CG) on running performance while assessing physiological and perceptual factors. Therefore, this study investigated how the clothing pressure of two types of Calf CG, CG1 and CG2, affects muscle fatigue and activation during running.
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Yunchu Yang, Weiyuan Zhang and Cong Shan
The paper aims to provide an overview of the area of digital pattern developing for customized apparel.
Abstract
Purpose
The paper aims to provide an overview of the area of digital pattern developing for customized apparel.
Design/methodology/approach
The paper outlines several methods of digital pattern developing for customized apparel, and discusses the principles, characters and applications. Digital pattern developing process has two paths. One path develops apparel according to traditional 2D pattern‐making technology. There are three methods: parametric design, traditional grading technique, and pattern generating based on artificial intelligence (AI). Another path develops pattern through surface flattening directly from individual 3D apparel model.
Findings
For parametric method, it can improve greatly the efficiency of pattern design or pattern alteration. However, the development and application of parametric Computer‐Aided‐Design (CAD) systems in apparel industry are difficult, because apparel pattern has fewer laws in graphical structure. For grading technique, it is the most practical method because of its simple theory, with which pattern masters are familiar. But these methods require users with higher experience. Creating expert pattern system based on AI can reduce the experience requirements. Meanwhile, a great deal of experiments should be conducted for each garment with different style to create their knowledge databases. For 3D CAD technology, two methods of surface flattening have been outlined, namely geometry flattening and physical flattening. But many improvements should be done if the 3D CAD systems are applied in apparel mass customization.
Originality/value
The paper provides information of value to the future research on developing a practical made‐to‐measure apparel pattern system.
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Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…
Abstract
Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.
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This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper…
Abstract
This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.
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Minghao Wang, Ming Cong, Dong Liu, Yu Du, Xiaojing Tian and Bing Li
The purpose of this study is to designed a robot odometry based on three dimensional (3D) laser point cloud data, inertial measurement unit (IMU) data and real-time kinematic…
Abstract
Purpose
The purpose of this study is to designed a robot odometry based on three dimensional (3D) laser point cloud data, inertial measurement unit (IMU) data and real-time kinematic (RTK) data in underground spatial features and gravity fluctuations environment. This method improves the mapping accuracy in two types of underground space: multi-layer space and large-scale scenarios.
Design/methodology/approach
An IMU–Laser–RTK fusion mapping algorithm based on Iterative Kalman Filter was proposed, and the observation equation and Jacobian matrix were derived. Aiming at the problem of inaccurate gravity estimation, the optimization of gravity is transformed into the optimization of SO(3), which avoids the problem of gravity over-parameterization.
Findings
Compared with the optimization method, the computational cost is reduced. Without relying on the wheel speed odometer, the robot synchronization localization and 3D environment modeling for multi-layer space are realized. The performance of the proposed algorithm is tested and compared in two types of underground space, and the robustness and accuracy in multi-layer space and large-scale scenarios are verified. The results show that the root mean square error of the proposed algorithm is 0.061 m, which achieves higher accuracy than other algorithms.
Originality/value
Based on the problem of large loop and low feature scale, this algorithm can better complete the map loop and self-positioning, and its root mean square error is more than double compared with other methods. The method proposed in this paper can better complete the autonomous positioning of the robot in the underground space with hierarchical feature degradation, and at the same time, an accurate 3D map can be constructed for subsequent research.
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Yuan George Shan and Indrit Troshani
The study improves current understanding concerning the implications of digital corporate reporting technology on the informativeness of accounting information.
Abstract
Purpose
The study improves current understanding concerning the implications of digital corporate reporting technology on the informativeness of accounting information.
Design/methodology/approach
It looks at how XBRL, an exemplar digital corporate financial reporting technology, affects value relevance of accounting information in the US and Japan, two key jurisdictions where XBRL has been mandated. We operationalise stock price and return value relevance models to assess and compare predicted associations between selected accounting measures and market value of equity in these countries.
Findings
We predict that the selected accounting measures are more value relevant after XBRL was mandated than before. We find evidence to support our prediction for the US sample. We also predict and find that the contribution of XBRL to the value relevance of the selected accounting measures is greater in the US than in Japan. Overall, our evidence provides support that digital corporate reporting technology enhances relevance and reliability of accounting measures.
Originality/value
The study appears to be the first to have examined the impact of XBRL on value relevance whilst comparing between two major jurisdictions. The study extends emerging but limited literature concerning the benefits of digital corporate financial reporting for enhancing the communication between firms and users of financial information. The findings are useful to both users of financial information and standard setters.
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Jianli Cong, Hang Zhang, Zilong Wei, Fei Yang, Zaitian Ke, Tao Lu, Rong Chen, Ping Wang and Zili Li
This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration. Consequently, a low-cost, data-driven approach…
Abstract
Purpose
This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body acceleration. Consequently, a low-cost, data-driven approach was proposed for analyzing speed-related acceleration limits in metro systems.
Design/methodology/approach
A portable sensing terminal was developed to realize easy and efficient detection of car body acceleration. Further, field measurements were performed on a 51.95-km metro line. Data from 272 metro sections were tested as a case study, and a quantile regression method was proposed to fit the control limits of the car body acceleration at different speeds using the measured data.
Findings
First, the frequency statistics of the measured data in the speed-acceleration dimension indicated that the car body acceleration was primarily concentrated within the constant speed stage, particularly at speeds of 15.4, 18.3, and 20.9 m/s. Second, resampling was performed according to the probability density distribution of car body acceleration for different speed domains to achieve data balance. Finally, combined with the traditional linear relationship between speed and acceleration, the statistical relationships between the speed and car body acceleration under different quantiles were determined. We concluded the lateral/vertical quantiles of 0.8989/0.9895, 0.9942/0.997, and 0.9998/0.993 as being excellent, good, and qualified control limits, respectively, for the lateral and vertical acceleration of the car body. In addition, regression lines for the speed-related acceleration limits at other quantiles (0.5, 0.75, 2s, and 3s) were obtained.
Originality/value
The proposed method is expected to serve as a reference for further studies on speed-related acceleration limits in rail transit systems.
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Yongyao Li, Ming Cong, Dong Liu, Yu Du, Minjie Wu and Clarence W. de Silva
Rigid robotic hands are generally fast, precise and capable of exerting large forces, whereas soft robotic hands are compliant, safe and adaptive to complex environments. It is…
Abstract
Purpose
Rigid robotic hands are generally fast, precise and capable of exerting large forces, whereas soft robotic hands are compliant, safe and adaptive to complex environments. It is valuable and challenging to develop soft-rigid robotic hands that have both types of capabilities. The paper aims to address the challenge through developing a paradigm to achieve the behaviors of soft and rigid robotic hands adaptively.
Design/methodology/approach
The design principle of a two-joint finger is proposed. A kinematic model and a stiffness enhancement method are proposed and discussed. The manufacturing process for the soft-rigid finger is presented. Experiments are carried out to validate the accuracy of the kinematic model and evaluate the performance of the flexible body of the finger. Finally, a robotic hand composed of two soft-rigid fingers is fabricated to demonstrate its grasping capacities.
Findings
The kinematic model can capture the desired distal deflection and comprehensive shape accurately. The stiffness enhancement method guarantees stable grasp of the robotic hand, without sacrificing its flexibility and adaptability. The robotic hand is lightweight and practical. It can exhibit different grasping capacities.
Practical implications
It can be applied in the field of industrial grasping, where the objects are varied in materials and geometry. The hand’s inherent characteristic removes the need to detect and react to slight variations in surface geometry and makes the control strategies simple.
Originality/value
This work proposes a novel robotic hand. It possesses three distinct characteristics, i.e. high compliance, exhibiting discrete or continuous kinematics adaptively, lightweight and practical structures.
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This study aims to examine the relationship between objective and subjective aspects of financial well-being, the role of family financial support and depression symptoms of…
Abstract
Purpose
This study aims to examine the relationship between objective and subjective aspects of financial well-being, the role of family financial support and depression symptoms of Chinese older adults.
Design/methodology/approach
This study used two waves (2015 and 2018) of the Harmonized China Health and Retirement Longitudinal Study. Two financial ratios: the expenditure-to-income ratio and the financial assets ratio, were used to measure the objective aspect of financial well-being. Perceived money management difficulty was employed to measure the subjective aspect of financial well-being. Depression symptoms were measured using the Center for Epidemiologic Studies Depression Scale (CES-D) score. Three analytical models, including an ordinary least squares (OLS) model, an OLS model controlling for lagged depression and a random effects model using panel data, were used to examine the relationships between the objective and subject aspects of financial well-being and depression.
Findings
The results from the three models showed consistent relationships: the expenditure-to-income ratio was a positive contributor, while the financial assets ratio was a negative contributor to depression of older adults in China. The robustness check using binary-coded financial ratio thresholds showed that reaching the suggested thresholds was negatively associated with depression. Perceived money management difficulty contributed positively to depression. The robustness check using the fixed effects model showed no significance of the two ratios, while perceived money management difficulty was positively associated with depression. The insignificance might be due to data limitation (limited waves or rare changes across waves).
Originality/value
The findings indicate that both objective and subjective financial well-being matters in relation to depression symptoms and, therefore, to the overall mental health of the Chinese elderly. Developments in public policies are needed to promote accessible financial services, assistance programs, mental health services and facilities for the older population in China.
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Lucas Liang Wang, Qing Dai and Yan Gao
New venture status is the most prominent feature of entrepreneurial startups, but its performance implications have remained under-studied. This study aims to bridge this…
Abstract
Purpose
New venture status is the most prominent feature of entrepreneurial startups, but its performance implications have remained under-studied. This study aims to bridge this knowledge void and offer precise guidelines for startup managers in boosting performance.
Design/methodology/approach
The study develops and tests a multi-perspective model on the linkage between new venture status and firm performance by integrating I/O economics, resource-based view and dynamic capability perspective. The arguments from the first two perspectives point to an adverse effect of new venture status, which is contingent, respectively, on business differentiation and resource endowments. The third perspective grounds a positive relationship between new venture status and performance, which is more pronounced for firms with weaker dynamic capabilities.
Findings
Quantitative evidence from a sample of new and established firms in China shows that the direct effect of new venture status is negative but insignificant. Neither business differentiation nor dynamic capabilities moderate the relationship. Low resource endowments, however, reinforce the negative influence of new venture status. New venture status, thus, shapes firm performance through resource scarcity from resource-based view rather than competitive vulnerability from I/O economics or strategic flexibility from dynamic capability perspective.
Originality/value
Newness and new venture performance have both been extensively examined in literature. But the relationship between them has remained largely omitted. The multi-perspective model and the findings in this study help clarify the confusion as to whether newness is good or bad in the context of an emerging market and reveals the subtle mechanism the effect of newness unfolds.
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