A network model of the entorhinal cortex layer II that consisted of stellate cells and an interneuron was constructed. The stellate cell reproduced subthreshold oscillations in the theta range as observed in physiolog...
详细信息
A network model of the entorhinal cortex layer II that consisted of stellate cells and an interneuron was constructed. The stellate cell reproduced subthreshold oscillations in the theta range as observed in physiological experiments. The subthreshold oscillations were recurrently synchronized through an inhibitory interneuron, and theta rhythm was generated. Anatomical evidences suggest that the layers II and V of the entorhinal cortex and the hippocampus may form a loop circuit with a delay time of about 25 ms for signals going around. With the loop circuit introduced to the present model, the stellate cells that represent spatial information fired successively at intervals of 25 ms, in depolarized phases of the theta cycles. The present entorhinal cortex model with the loop circuits reproduced the phase precession, which has been observed experimentally as a characteristic of place cells.
In this paper, we study how to collect n balls moving with constant velocities in the Euclidean plane by k robots moving on straight track-lines through the origin. Since all the balls might not be caught by robots, d...
详细信息
In this paper, we study how to collect n balls moving with constant velocities in the Euclidean plane by k robots moving on straight track-lines through the origin. Since all the balls might not be caught by robots, differently from Moving-Target TSP, we consider the following 3 problems in various situations: (i) deciding if k robots can collect all n balls, (ii) maximizing the number of the balls collected by k robots, and (iii) minimizing the number of the robots to collect all n balls. The situations considered here contain the cases in which track-lines are given (or not), and track-lines are identical (or not). For all problems and situations, we provide polynomial time algorithms or proofs of intractability, which clarify the tractability-intractability frontier in the ball collecting problems in the Euclidean plane.
It is possible to enjoy the quality of service related informations of a single node or a link between two nodes, which is understandable for the technical people only. Yet, there is no zone-based quality of service i...
详细信息
An increasing biped robot development may be viewed in terms of realization of autonomous works in real world, where robot motion with lifting and/or carrying of heavy objects must be designed. Such motion control of ...
详细信息
An increasing biped robot development may be viewed in terms of realization of autonomous works in real world, where robot motion with lifting and/or carrying of heavy objects must be designed. Such motion control of biped robot working by himself is an important issues, in which many configurations and motions appear depending on position of robot and object. Isaka et al. analyzed the lifting motion of skilled lifter and mentioned that the configuration of lifting is important to realize the efficient lifting with small burden to the lower back. In their analysis the motion was limited for weight lift, and the object's position was fixed. So, it is required to analyze various human lifting motions in many situations for new biped robot control. Our study aims at realization of biped robot that can walk and lifting heavy objects. In this paper, dynamic characteristics of human lifting movement are analyzed through lifting of barbell in various situations. Furthermore, based on the lifting analysis, the comparison of motion control between lifting and jumping is discussed.
Information technology is providing manufacturers with additional flexibility with regard to their supply chain network choices. Our research studies supply chain network organization structures categorized by the org...
Information technology is providing manufacturers with additional flexibility with regard to their supply chain network choices. Our research studies supply chain network organization structures categorized by the organic and mechanistic management control structures. The structural impacts on cost and fill rate performance are studied in two-echelon and two-supply-chain network organization models under different market coordination conditions using system dynamic simulations. Our results show significant effects of demand and network structural factors, and their interactions, on these measures. As demand becomes dynamic, the cooperative interaction model, where supply chains cooperate to satisfy customer demand, is found to have better system performance than the competitive supply chain model. The analysis also suggests that increasing the responsiveness at the downstream plant is particularly important to the overall system performance improvement.
We propose a method of semantically nonmonotonic reasoning in prioritized knowledge bases based on incomplete information systems and granular reasoning. Our nonmonotonic reasoning is characterized as "reasoning ...
详细信息
We propose a method of semantically nonmonotonic reasoning in prioritized knowledge bases based on incomplete information systems and granular reasoning. Our nonmonotonic reasoning is characterized as "reasoning with disregard of difference of detail." We provide granularized models and priority of each rule, and formulate the method of semantically non-monotonic reasoning based on the idea of ignored sets, rejected sets and possible tuples of atomic sentences that we propose.
The RFID system is attracting attentions in the field of automatic identification. Especially, they need a system that can identify a thousand of tags at a time in practical use. We proposed a communication scheme in ...
详细信息
The RFID system is attracting attentions in the field of automatic identification. Especially, they need a system that can identify a thousand of tags at a time in practical use. We proposed a communication scheme in combination of time hopping CDMA, CRC error-detecting, and repetition of transmission for error recovery to resolve collision problems by simple circuits. The scheme realizes identification of a thousand in 300 msec with low error rate of 1.214 /spl times/ 10/sup -11/. This paper presents an experimental tag circuit which achieves low power operation of 23.4 /spl mu/W with the core area of 12520 /spl mu/m/sup 2/.
This paper focuses on implementation issues of a virtual environment to support the interaction with a coordinate measuring machine (CMM), which is used to measure dimensions and form of mechanical parts. First, it gi...
详细信息
This paper focuses on implementation issues of a virtual environment to support the interaction with a coordinate measuring machine (CMM), which is used to measure dimensions and form of mechanical parts. First, it gives an overview of the implementation, presenting the software "Avalon" and the basic architecture of the developed application. Then, it describes the execution environment, including the description of equipments and devices, characteristics and constraints, and system execution. Finally, it presents the conclusions of the work.
This paper reports a new dynamic programming environment for FDNet. The FDNet was designed as a flexible system that can accept new functions by reforming the network itself. Another feature that the relation networks...
详细信息
This paper reports a new dynamic programming environment for FDNet. The FDNet was designed as a flexible system that can accept new functions by reforming the network itself. Another feature that the relation networks in FDNet are described by XML can help to expand the network scale easily. Our new dynamic editing system uses the feature, and communicates via TCP/IP network for editing. Some trials reported in this paper shows a capability of an automatic self-editing function in the imitating robot system.
Weather information is an excellent representation of atmospheric phenomenon. People with little or no atmospheric knowledge can understand weather forecasts and make good use of it in their daily life. Although Inter...
详细信息
Weather information is an excellent representation of atmospheric phenomenon. People with little or no atmospheric knowledge can understand weather forecasts and make good use of it in their daily life. Although Internet information flow does not include this system, it is essential for fitting both the technical and non-technical users. Users need to see the current traffic status of their own ISP or zone, even if some users curiously want to see other zones or the global traffic status. To fulfill this requirement for users, this paper approached a new model called the Ryuki model. In the four planes of the Ryuki model, we captured flow information from the bottom plane, estimated the flows, and introduced three mathematical indices in the second plane. The indices are Ryuki temperature, Ryuki pressure and Ryuki density. The third plane is the service plane where two types of services are introduced. And finally, the top plane represents the network status of the zone. Zone is used as an autonomous system (AS) in this document. A well-known network simulator is used in the simulation for collecting network traffic to estimate the service (QoS and CoS) related information.
暂无评论