A control method with pheromone information for a transport system

Since the control methods of a transport system between processing machines are specialized for each layout of the system, it is difficult to design prompt schedules and control logic for new complicated systems, especially in cases of machine faults or restructuring the system to modify the layout. In this article, we describe a multiagent transport control system which utilizes pheromone information. Each element of the system acts as an agent and estimates the appropriate path and time to drive out the products using information obtained by communication with other elements as well as pheromone information deposited on the tracks of the products.     

Navigation system for an autonomous robot using an ocellus camera in an indoor environment

Autonomous and mobile robots are being expected to provide various services in human living environments. However, many problems remain to be solved in the development of autonomous robots that can work like humans. When a robot moves, it is important that it be able to have self-localization abilities and recognize obstacles. For a human, the present location can be correctly checked through a comparison between memorized information assuming, it is correct, and the present situation. In addition, the distance to an object and the perception of its size can be estimated by a sense of distance based on memory or experience. Therefore, the environment for robotic activity assumed in this study was a finite-space such as a family room, an office, or a hospital room. Because an accurate estimation of position is important to the success of a robot, we have developed a navigation system with self-localization ability which uses only a CCD camera that can detect whether the robot is moving accurately in a room or corridor. This article describes how this system has been implemented and tested with our developed robot.     

Detection of environmental changes from network structure

We studied the networks of the temperature record in the atmosphere. They are made by the strength of the synchronization, including the delay between temperatures at locations on Earth. We consider these locations as nodes, and we consider a pair of locations as a link if the synchronization between them is stronger than a threshold. The network is scale-free, which is thought to contribute to the stability of the climate. This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27, 2007     

A counterexample to a proposed dynamic programming algorithm for optimal bid construction in an auction-based fully distributed manufacturing system

The paper by Veeramani and Wang (Int J Adv Manuf Technol 28:541–550, 2006) published in this journal offers a general bid construction scheme for minimizing the job flow time in auction-based manufacturing control and claims the optimality of the procedure. The purpose of this note is to provide a small example, in which their proposed new method fails to produce an optimal solution. We also address efficient correct algorithms so as to protect the readers from mistakenly believing that their new procedure is a better way of computing solutions.     

Magnetic Correlation in BETS2(Cl2TCNQ)

We carried out⁷⁷Se NMR measurements on BETS₂(Cl₂TCNQ) under pressure in order to investigate the magnetic properties of the insulating state which appears above 0.6 GPa. The relaxation rate 1/T₁ at 0.7 GPa shows small peak-like anomaly at 20 K, indicating a spin density wave transition as observed in BETS₂(Br₂TCNQ).     

Impact of Multimedia Traffic Characteristics on ATM Network Configuration

This paper proposes a new topological designmethod, named BXCQ, which optimizes logical networkconfiguration while guaranteeing Quality-of-Service(QoS) requirements for each service class in an ATMnetwork. The BXCQ method determines the optimum logicalnetwork topology associated with each service class soas to minimize network cost. In our previously proposedFull-Net architecture these different logical topologies can be suitably mapped at the sametime on the same ATM physical network by using theVirtual Channel Handler (VCH) to create differentlogical interconnection networks. The BXCQ method allows us to clarify the relations between multimediatraffic characteristics and desirable logical networkconfigurations in Full-Net. Evaluation results suggestthat a service class that is bursty, delay tolerant, and cell loss sensitive with small demandshould be supported by a loop-like topology. This studywill be useful for designing flexible and cost-effectivemultimedia networks that can also adapt to not-yet-known services.     

Feasibility of a 1,400 m Span Steel Cable-Stayed Bridge

This paper describes the feasibility of 1,400 m steel cable-stayed bridges from both structural and economic viewpoints. Because the weight of a steel girder strongly affects the total cost of the bridge, the writers present a procedure to obtain a minimum weight for a girder that ensures safety against static and dynamic instabilities. For static instability, elastoplastic, finite-displacement analysis under in-plane load and elastic, finite-displacement analysis under displacement-dependent wind load are conducted; for dynamic instability, multimodal flutter analysis is carried out. It is shown that static critical wind velocity of lateral torsional buckling governs the dimension of the girder. Finally, the writers briefly compare a cable-stayed bridge with suspension bridge alternatives.     

BaO—CaO—Na2O—CaF2—Cr2O3渣系的不锈钢脱磷

测定了１５００℃时磷在ＢａＯ－ＣａＯ－Ｎａ２Ｏ－ＣａＦ２－Ｃｒ２Ｏ３渣子和０．１２Ｃ－０．７１Ｓｉ－１８Ｃｒ不锈钢熔体之间的分配比，试验结果表明，该渣系的不锈钢脱磷能力比ＣａＯ基渣好，与ＢａＯ基渣相当。     

Inorganic/Organic Double‐Network Gels Containing Ionic Liquids

Highly robust ion gels, termed double‐network (DN) ion gels, composed of inorganic/organic interpenetrating networks and a large amount of ionic liquids (ILs), are fabricated. The DN ion gels with an 80 wt% IL content show extraordinarily high mechanical strength: more than 28 MPa of compressive fracture stress. In the DN ion gel preparation, a brittle inorganic network of physically bonded silica nanoparticles and a ductile organic network of polydimethylacrylamide (PDMAAm) are formed in the IL. Because of the different reaction mechanisms of the inorganic/organic networks, the DN ion gels can be formed by an easy and free‐shapeable one‐pot synthesis. They can be prepared in a controllable manner by manipulating the formation order of the inorganic and organic networks via not only multistep but also single‐step processes. When silica particles form a network prior to the PDMAAm network formation, DN ion gels can be prepared. The brittle silica particle network in the DN ion gel, serving as sacrificial bonds, easily ruptures under loading to dissipate energy, while the ductile PDMAAm network maintains the shape of the material by the rubber elasticity. Given the reversible physical bonding between the silica particles, the DN ion gels exhibit a significant degree of self‐recovery by annealing.     

Determining number of clusters and prototype locations via multi-scale clustering

In clustering algorithms, it is usually assumed that the number of clusters is known or given. In the absence of such a priori information, a procedure is needed to find an appropriate number of clusters. This paper presents a clustering algorithm that incorporates a mechanism for finding the appropriate number of clusters as well as the locations of cluster prototypes. This algorithm, called multi-scale clustering, is based on scale-space theory by considering that any prominent data structure ought to survive over many scales. The number of clusters as well as the locations of cluster prototypes are found in an objective manner by defining and using lifetime and drift speed clustering criteria. The outcome of this algorithm does not depend on the initial prototype locations that affect the outcome of many clustering algorithms. As an application of this algorithm, it is used to enhance the Hough transform technique.