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Real‐time multimedia supervisory systems generally include a distributed system that delivers live video input captured with cameras at the watched person's site, using a PC or hand‐held device at the distant supervisor's site. The system comprises many entities such as cameras for image capture, transmission software, network connections, receiver software, a display device, multimedia processing software and hardware, control software, etc. The purpose of this paper is to realize a safe and convenient supervisory system that autonomously provides users with services that fulfill users' requirements related to quality and privacy in a ubiquitous information environment.

A system is designed by integrating environmental information acquired from the real world and knowledge related to human social activities. A real space understanding mechanism is proposed to infer the situations and relationships of users by combining sensing information and social knowledge. Social knowledge related to human relationships, the life style of the watched person, home structure, etc. is used with ontology to infer the situations of users.

An early prototype was implemented for supervising elderly people and some experiments were performed based on several scenarios. Results obtained from some experiments confirmed that this supervisory system can provide real‐time multimedia supervisory services for elderly people, with reasonable quality‐of‐service and privacy that meet the users' requirements.

The system described in this paper assesses the situation of users and surrounding environmental information to provide appropriate supervisory services. This paper provides insight into the design and development of ubiquitous application systems to realize comfortable and safe services using a combination of environmental information and social knowledge.

The purpose of this paper is to focus on sensor data fluctuations. Context‐aware applications in the real world adapt their behavior to contexts abstracted from real‐world situations sensed as physical quantities by heterogeneous and distributed sensors. Most of the adaptations are programmed as rules derived from human experience in making environments comfortable and efficient. Preparation of sufficient rules, however, is difficult because oversights and exceptional contexts are inevitable.

This paper, focuses on sensor data fluctuations and calculates the probabilities indicating the frequency of such fluctuations.

The results help to confirm the preset rules of the context‐aware applications and find previously unnoticed situations that the context‐aware applications should cope with.

The paper shows how this method is applied to log data captured in an office in order to evaluate the method's capabilities and consider the feasibility of abstracting the newly observed situations into rules.

Satellite networking will be an important component of future ubiquitous communications systems. Satellite networks will be especially useful to interconnect remote sensor networks. Therefore, satellite networks should provide the needed QoS, differentiation of services and at the same time keep the required scalability. The purpose of this paper is to propose a new Diffserv‐based scheme of bandwidth allocation during congestion, called proportional allocation of bandwidth (PAB).

The paper suggests a method for implementing PAB without storing per‐flow state, which makes the scheme scalable and simple and shows, by simulation, the advantages of using PAB in IP satellite networks.

The paper finds that PAB can be used in geostationary earth orbit, MEO and low earth orbit satellite networks. In PAB, during congestion all flows get a share of IP available bandwidth, which is in proportion to their subscribed information rate.

The simulations described in this paper show that the performance of PAB scheme is good on congested satellite networks.

Energy consumption is a fundamental concern in wireless multimedia sensor networks, even more than that in traditional wireless sensor networks. In fact, sensors are battery‐constrained devices, while multimedia applications, which require higher transmission rates and more extensive processing capacity, produce large quantities of data. The purpose of this paper is to propose a method which could save multimedia nodes' energy during their sleeping and transmitting phases and effectively bring down energy consumption.

Based on the location and direction angle of nodes, areas of the overlapping sensing region between adjacent nodes could be calculated and a sleeping strategy is carried out to reduce energy consumption of inactive nodes. Moreover, an improved image comparison and block transmission methods by utilizing the sequence similar detection arithmetic theory is brought up as well to further save the node's energy.

With the help of the mobile nodes and by dividing the network into grids, sensing direction of multimedia node as well as the area of the overlapping sensing region could be obtained which provide a basis for the sleeping strategy. Furthermore, energy consumption on transmission is also reduced by only transmitting the unmatched blocks. Simulation results show that this method obtains satisfactory performance on prolonging the networks' lifetime.

This paper is of value in presenting an effective energy‐saving strategy for wireless multimedia sensor networks.

Intelligent agents are becoming an essential part of collaborative virtual environments. The purpose of this paper is to present an architecture of a learning agent that is able to utilize machine learning techniques to monitor the user's actions.

A learning agent is developed and integrated into federated collaborative virtual workspace.

The experimental results showed that the combination of genetic algorithms and reinforcement learning algorithms provides the agent with better learning capability resulting in better predictions for the user.

This paper provides experimental results and a performance analysis in terms of accuracy of predictions, processing time, and memory utilization of the agent.

With the wide spread of the ubiquitous environment, it is necessary to provide adequate multimedia communication services for various users under various networked environments. In such situations, it is essential to organize multimedia software components dynamically to provide necessary services for effective service provision based on the system's operational environment during the run time of the system. The purpose of this paper is to propose a new scheme for observing and controlling behavior of the QoS‐aware agent organization, which provides a flexible QoS control of multimedia service components.

Two models are proposed in this paper: a flexible distributed system (FDS) model and a behavioral characteristics model (BCM), which were applied to the design of network middleware constructed as a QoS‐aware agent organization. Experiments were performed using the middleware prototype system.

Results confirmed that the proposed models provide an effective scheme for designers of multimedia communication services.

This paper shows that using the FDS model, a multiagent system can be designed and constructed systematically. In addition, using BCM, a multiagent system with flexible QoS control capability can deal with changes of the system's operational situations and thereby maintain the required QoS as well as its behavioral characteristics.

The purpose of this paper is to focus on the method to improve real‐time property of real‐time operating system (RTOS), one of the most essential problems in RTOS studies.

Improved task models are proposed based on the basic task and extended task models of OSEK operating system (OSEK OS). According to different task states, optimized scheduling algorithm was put forward. Some examples in a practical environment are described that illustrate the value of the method.

This method has been successfully implemented and evaluated in an OSEK compatible operating system, SmartOSEK OS. The time cost of context switching is decreased and the efficiency is enhanced.

The improvement gained depends on the ratio of each strategy applied. In case the strategy D is applied too many times, the performance will be lead to a depressing result. For real‐time system, a long‐lived process that maybe increase the ratio of strategy D is not the optimal selection.

Dividing the ready state of task into intermediate state and initial state, can optimize the process of task context switching for OSEK OS. The method has proven to be useful in improving the real‐time property of RTOS.

Anchored in the role of a social arbiter, the purpose of this study is to examine whether and how media coverage has an impact on CEO overconfidence and further explore how media ownership and Confucianism affect the relationship in the Chinese context.

Using a sample of 1,492 Chinese listed companies from 2010 to 2015, the study adopts random effects models to empirically analyze the effect of media coverage on CEO overconfidence and the roles of media ownership and Confucianism.

The paper finds that media coverage is significantly and positively associated with CEO overconfidence, and the positive relationship between media coverage and CEO overconfidence becomes stronger for state-controlled media. What is more, the influence of media coverage on CEO overconfidence is attenuated for those firms located in stronger Confucianism atmosphere. A further analysis reveals that different tenors of media coverage yield asymmetric effects.

The paper provides a new and solid support for the argument that media praise stimulates CEO overconfidence and increases the knowledge about under what conditions CEO overconfidence varies, broadly speaking which fosters the development of upper echelons theory (UET). Meanwhile, the results extend the literature on media effect and information processing. The findings are also beneficial to improve corporate decisions and government regulation on Chinese media systems.

This study examines how informal business networks achieve marketing goals in socially uncertain contexts. Drawing from multiple historical sources, Shangbangs, a type of business network that thrived in pre-1949 China, are analyzed.

The Critical Historical Research Method (CHRM) undergirds a study of Shangbangs’ historicity (i.e. their socio-historically embedded multiplicity, including organizational forms, activities and connotations.

As informal regional, professional, project-based, special-product-based or mixed marketing networks, Shangbangs relied on “flexible specialization” and coupled multiple business needs to market goods and services, business organizations, specific social values and, when necessary, to debrand business rivals.

This analysis extends theories about marketing networks by probing their subtypes, diverse marketing activities, multipronged channels and relationship building with social entities (including underground societies, business associations and guilds) in response to pre-1949 China’s market uncertainties. Substantiating an alternative approach to “flexible specialization” and marketing innovations within the pre-1949 Chinese economy shows how a parallel theoretical framework can complement western-based marketing theories.

This first comprehensive analysis of Shangbangs, an innovative historical Chinese marketing network outside the conventional market-corporate dichotomy, can inform theory building for marketing strategy-making and management conditioned by social contexts.