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1 – 10 of 129Zhe Yu, Raquel Prado, Steve C. Cramer, Erin B. Quinlan and Hernando Ombao
We develop a Bayesian approach for modeling brain activation and connectivity from functional magnetic resonance image (fMRI) data. Our approach simultaneously estimates local…
Abstract
We develop a Bayesian approach for modeling brain activation and connectivity from functional magnetic resonance image (fMRI) data. Our approach simultaneously estimates local hemodynamic response functions (HRFs) and activation parameters, as well as global effective and functional connectivity parameters. Existing methods assume identical HRFs across brain regions, which may lead to erroneous conclusions in inferring activation and connectivity patterns. Our approach addresses this limitation by estimating region-specific HRFs. Additionally, it enables neuroscientists to compare effective connectivity networks for different experimental conditions. Furthermore, the use of spike and slab priors on the connectivity parameters allows us to directly select significant effective connectivities in a given network.
We include a simulation study that demonstrates that, compared to the standard generalized linear model (GLM) approach, our model generally has higher power and lower type I error and bias than the GLM approach, and it also has the ability to capture condition-specific connectivities. We applied our approach to a dataset from a stroke study and found different effective connectivity patterns for task and rest conditions in certain brain regions of interest (ROIs).
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The purpose of this paper is to suggest an emerging paradigm by synthesizing what is presented at an Asian Productivity Organization (APO) study meeting. The meeting focuses on…
Abstract
Purpose
The purpose of this paper is to suggest an emerging paradigm by synthesizing what is presented at an Asian Productivity Organization (APO) study meeting. The meeting focuses on business strategy development. The author acts as the Chief Facilitator during the meeting. The paradigm is intended to help CEOs of firms in Asia to re‐model their businesses in light of rising, innovative China.
Design/methodology/approach
The APO (Japan) and China Productivity Center (Taipei, Taiwan) recently organized a Taipei study meeting. The theme of the meeting was on “post‐global financial crisis, (small, medium sized enterprises) SMEs' business development strategy”. In‐depth, rich experiences were shared during the discussion following the presentations. Founding CEOs, Presidents and senior leaders from industry were involved from the following countries: India, Indonesia, Iran, Japan, Korea, Malaysia, Philippines, Singapore, Taiwan, Thailand, and Vietnam. Reflecting upon the materials presented, the author develops, through synthesis, an emerging Asian paradigm for evolving newer business models as part of organizational strategy development.
Findings
People always compete in the future. For businesses, besides keeping old customers, it is about the winning of contracts. For example, in the telecom industry, there is intense competition to produce newer, more innovative hand‐held devices. In the coming years, products using Chinese innovation will actively compete in the global marketplace. This pan‐Asia paradigm is useful for CEOs to begin to think about re‐shaping their business model to compete in the next wave.
Originality/value
Since the industrial age and up to very recently, ideas, concepts, methods, techniques, inventions, innovations and business models have been “borrowed” from the West by Asians and adapted to local environments. With the global crisis and consequently a deep weakening of Europe and the USA, there is a growing consensus among top management in Asia: that new thinking on management, for example in business modeling, ought to be drawn from the East. Thus, it is timely for the APO to be organizing such a study meeting.
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Juyan Zhang and Glen T. Cameron
In this historical analysis, Jacques Ellul’s theory of propaganda is applied to analyse the changes of China’s propaganda. It is found that China’s propaganda is undergoing…
Abstract
In this historical analysis, Jacques Ellul’s theory of propaganda is applied to analyse the changes of China’s propaganda. It is found that China’s propaganda is undergoing structural transformations from depending on human organisation to extensive control and use of media technology. Sociological propaganda as a complement to political propaganda has significantly expanded; integration propaganda replaced agitation propaganda. International image management by the government has become a new dimension of China’s propaganda. The research is one of the first to observe such structural changes.
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Purpose
The purpose of this paper is to propose a two-degrees-of-freedom wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring, in order to improve the robot’s athletic ability, load capacity and rigidity, and to ensure the coordination of multi-modal motion.
Design/methodology/approach
First, based on the rotation transformation matrix and closed-loop constraint equation of the parallel trunk joint mechanism, the mathematical model of its inverse position solution is constructed. Then, the Jacobian matrix of velocity and acceleration is derived by time derivative method. On this basis, the stiffness matrix of the parallel trunk joint mechanism is derived on the basis of the principle of virtual work and combined with the deformation effect of the rope driving pair and the spring elastic restraint pair. Then, the eigenvalue distribution of the stiffness matrix and the global stiffness performance index are used as the stiffness evaluation index of the mechanism. In addition, the performance index of athletic dexterity is analyzed. Finally, the distribution map of kinematic dexterity and stiffness is drawn in the workspace by numerical simulation, and the influence of the introduced spring on the stiffness distribution of the parallel trunk joint mechanism is compared and analyzed. It is concluded that the stiffness in the specific direction of the parallel trunk joint mechanism can be improved, and the stiffness distribution can be improved by adjusting the spring elastic structure parameters of the rope-driven branch chain.
Findings
Studies have shown that the wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism based on spring has a great kinematic dexterity, load-carrying capacity and stiffness performance.
Research limitations/implications
The soft-mixed structure is not mature, and there are few new materials for the soft-mixed mixture; the rope and the rigid structure are driven together with a large amount of friction and hindrance factors, etc.
Practical implications
It ensures that the multi-motion mode hexapod mobile robot can meet the requirement of sufficient different stiffness for different motion postures through the parallel trunk joint mechanism, and it ensures that the multi-motion mode hexapod mobile robot in multi-motion mode can meet the performance requirement of global stiffness change at different pose points of different motion postures through the parallel trunk joint mechanism.
Social implications
The trunk structure is a very critical mechanism for animals. Animals in the movement to achieve smooth climbing, overturning and other different postures, such as centipede, starfish, giant salamander and other multi-legged animals, not only rely on the unique leg mechanism, but also must have a unique trunk joint mechanism. Based on the cooperation of these two mechanisms, the animal can achieve a stable, flexible and flexible variety of motion characteristics. Therefore, the trunk joint mechanism has an important significance for the coordinated movement of the whole body of the multi-sport mode mobile robot (Huang Hu-lin, 2016).
Originality/value
In this paper, based on the idea of combining rigid parallel mechanism with wire-driven mechanism, a trunk mechanism is designed, which is composed of four spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism in series. Its spring-based wire-driven 4SPS/U rigid‒flexible parallel trunk joint mechanism can make the multi-motion mode mobile robot have better load capacity, mobility and stiffness performance (Qi-zhi et al., 2018; Cong-hao et al., 2018), thus improving the environmental adaptability and reliability of the multi-motion mode mobile robot.
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Rong Wang, Jin Wu, Chong Li, Shengbo Qi, Xiangrui Meng, Xinning Wang and Chengxi Zhang
The purpose of this paper is to propose a high-precision attitude solution to solve the attitude drift problem caused by the dispersion of low-cost micro-electro-mechanical system…
Abstract
Purpose
The purpose of this paper is to propose a high-precision attitude solution to solve the attitude drift problem caused by the dispersion of low-cost micro-electro-mechanical system devices in strap-down inertial navigation attitude solution of micro-quadrotor.
Design/methodology/approach
In this study, a three-stage attitude estimation scheme that combines data preprocessing, gyro drifts prediction and enhanced unscented Kalman filtering (UKF) is proposed. By introducing a preprocessing model, the quaternion orientation is calculated as the composition of two algebraic quaternions, and the decoupling feature of the two quaternions makes the roll and pitch components independent of magnetic interference. A novel real-time based on differential value (DV) estimation algorithm is proposed for gyro drift. This novel solution prevents the impact of quartic characteristics and uses the iterative method to meet the requirement of real-time applications. A novel attitude determination algorithm, the pre-process DV-UKF algorithm, is proposed in combination with UKF based on the above solution and its characteristics.
Findings
Compared to UKF, both simulation and experimental results demonstrate that the pre-process DV-UKF algorithm has higher reliability in attitude determination. The dynamic errors in the three directions of the attitude are below 2.0°, the static errors are all less than 0.2° and the absolute attitude errors tailored by average are about 47.98% compared to the UKF.
Originality/value
This paper fulfils an identified need to achieve high-precision attitude estimation when using low-cost inertial devices in micro-quadrotor. The accuracy of the pre-process DV-UKF algorithm is superior to other products in the market.
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Wu Yan and Lisa Catherine Ehrich
The purpose of this paper is to provide an understanding of principal preparation and training in China by providing a background discussion of principal preparation in a number…
Abstract
Purpose
The purpose of this paper is to provide an understanding of principal preparation and training in China by providing a background discussion of principal preparation in a number of countries. As an illustration, it provides an overview of the curriculum used in the initial preparation of school principals at Beijing Normal University.
Design/methodology/approach
The paper draws mainly on writing and research from China, Australia and the USA to explore principal preparation and training in China.
Findings
In addition to providing a rich description of principal preparation in China, the paper's main findings comprise seven key challenges that confront China as it endeavours to provide quality principal preparation. These challenges include China's diversity and uneven social, cultural and educational development; limited resources in some regions throughout China; the place and importance of study tours for principal preparation; the teaching approach used to train principals; the process used for assessing principal learning during their training programs; the limited transfer of learning from the classroom to the school environment; and the timing of training for principals.
Practical implications
Each of the challenges arising here raises important practical implications for developers of principal training programs.
Originality/value
The paper paints a picture of principal preparation in China and raises a number of issues and challenges with which it continues to grapple. Of note is that China is not alone in facing some of these ongoing concerns.
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Zhe Ouyang, Jiuchang Wei, Yu Xiao and Fei Wang
The purpose of this paper is to examine the impact of media attention on corporate disaster relief.
Abstract
Purpose
The purpose of this paper is to examine the impact of media attention on corporate disaster relief.
Design/methodology/approach
The authors used a matched sample research design, which is considered more appropriate than a random sample design for studying events that have low-occurrence rates in general. For each donor firm in the Yushu earthquake, the authors matched the firm with a non-donor firm in the same industry and with a firm size of within ±30 percent of the total assets in the year prior to the year of the occurrence of the Yushu earthquake. Then, using the Baidu engine, which is the most popular Chinese search engine, the authors captured the online media attention to the donor firms and their disaster relief.
Findings
The authors found that media attention drove corporate disaster relief.
Research limitations/implications
Although the authors highlighted the role of the media as an important stakeholder in influencing corporate disaster relief, the authors did not fully explore the media’s influence. Future research should delve more deeply into the impact of the tenor of media coverage on corporate disaster relief.
Originality/value
This study reveals that the media, a particularly powerful stakeholder, can be a corporate disaster relief driver in China.
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Chengxi Zhang, Jin Wu, Yulong Huang, Yu Jiang, Ming-zhe Dai and Mingjiang Wang
Recent spacecraft attitude control systems tend to use wireless communication for cost-saving and distributed mission purposes while encountering limited communication resources…
Abstract
Purpose
Recent spacecraft attitude control systems tend to use wireless communication for cost-saving and distributed mission purposes while encountering limited communication resources and data exposure issues. This paper aims to study the attitude control problem with low communication frequency under the sampled-data.
Design/methodology/approach
The authors propose constructive control system structures based on quantization and event-triggered methods for intra-spacecraft and multi-spacecraft systems, and they also provide potential solutions to shield the control system's data security. The proposed control architectures can effectively save communication resources for both intra-spacecraft and multi-spacecraft systems.
Findings
The proposed control architectures no longer require sensors with trigger-ing mechanism and can achieve distributed control schemes. This paper also provides proposals of employing the public key encryption to secure the data in control-loop, which is transmitted by the event-triggered control mechanism.
Practical implications
Spacecraft attempts to use wireless communication, yet the attitude control system does not follow up promptly to accommodate these variations. Compared with existing approaches, the proposed control structures can save communication resources of control-loop in multi-sections effectively, and systematically, by rationally configuring the location of quantization and event-triggered mechanisms.
Originality/value
This paper presents several new control schemes and a necessary condition for the employment of encryption algorithms for control systems based on event-based communication.
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