Visiting pebbles on rectangular grids: coordinating multiple robots in mobile fulfilment systems

Intelligent Service Robotics - Multi-robot path finding and coordination is one of the key performance-affecting subsystems of the overall robotic order fulfilment process for use in warehouse...     

Design and control of JAIST active robotic walker

This paper presents the design and control of a novel assistive robotic walker that we call “JAIST active robotic walker (JARoW)”. JARoW is developed to provide potential users with sufficient ambulatory capability in an efficient, cost-effective way. Specifically, our focus is placed on how to allow easier maneuverability by creating a natural interface between the user and JARoW. For the purpose, we develop a rotating infrared sensor to detect the user’s lower limb movement. The implementation details of the JARoW control algorithms based on the sensor measurements are explained, and the effectiveness of the proposed algorithms is verified through experiments. Our results confirmed that JARoW can autonomously adjust its motion direction and velocity according to the user’s walking behavior without requiring any additional user effort.     

On the Delay of a CNTFET with Undeposited CNTs by Gate Width Adjustment

This paper deals with the performance of a Carbon Nano Tube Field Effect Transistor (CNTFET) in the presence of undeposited CNTs as defects. A simulation-based analysis of delay degradation due to different features (such as chirality and defective CNT distribution) is initially pursued. Two solutions to mitigate the change in delay are proposed; these approaches are based on adjusting the gate width of the CNTFET by lithography (and removing CNTs) as part of the fabrication process. These two methods reduce the average delay and its deviation, respectively. A probabilistic delay analysis is then presented. The performance of the proposed two adjustment methods is evaluated by considering CNT features (such as chirality and defect distribution) deterministically and probabilistically. By deterministic (probabilistic) simulation, the first method reduces on average the delay by 6.968 % (7.811 %) while the deviation is increased (decreased) by 32.444 % (9.788 %). The second method reduces deterministically (probabilistically) on average the deviation by 44.159 % (47.476 %) with 2.166 % (4.409 %) delay reduction.     

An Intelligent Product Recommendation Model to Reflect the Recent Purchasing Patterns of Customers

Mobile Networks and Applications - This study suggests a new product recommendation model to reflect the recent purchasing patterns of customers. There are many methods to measure the similarity...     

Monocular depth estimation with multi-view attention autoencoder

Multimedia Tools and Applications - Depth map estimation from a single RGB image is a fundamental computer vision and image processing task for various applications. Deep learning based depth map...     

Tracking multiple moving targets with swarms of mobile robots

This paper presents a distributed approach to enable mobile robot swarms to track multiple targets moving unpredictably. The proposed approach consists of two constituent algorithms: local interaction and target tracking. When the robots are faster than the targets, Lyapunov theory can be applied to show that the robots converge asymptotically to each vertex of the desired equilateral triangular configurations while tracking the targets. Toward practical implementation of the algorithms, it is important to realize the observation capability of individual robots in an inexpensive and efficient way. A new proximity sensor that we call dual rotating infrared (DRIr) sensor is developed to meet these requirements. Both our simulation and experimental results employing the proposed algorithms and DRIr sensors confirm that the proposed distributed multi-target tracking method for a swarm of robots is effective and easy to implement.     

Effects of high pressure processing on fatty acid composition and volatile compounds in Korean native black goat meat

This study investigated the effects of high pressure processing (HPP) on fatty acid composition and volatile compounds in Korean native black goat (KNBG) meat. Fatty acid content in KNBG meat was not significantly (p > 0.05) different among the control goats and those subjected HPP. The 9,12-octadecadienoic acid and octadecanoic acid, well-known causes of off-flavors, were detected from meat of some KNBG. A difference between the control and HPP treatment was observed in the discriminated function analysis using an electronic nose. The results suggest that the volatile compounds in KNBG meat were affected by HPP.     

High temperature cracking of tungsten polycide films on quartz substrate

Investigation of high temperature cracking of tungsten polycide films on quartz reveals that the average thermal expansion mismatch stress and process-related local stress due to the interfacial roughening and voids may be major factors generating cracks in tungsten silicide. The silicide reaction and silicon crystallization at high temperature are responsible for interfacial roughening in silicon-rich silicide (WSi_x>2.3)and local voids in tungsten-rich silicide (WSi_x<2.3): high temperature annealing of silicon-rich silicide on a-Si/quartz allows silicon growth into the silicide, resulting in the interfacial roughening and thus increasing the local stress near the tips of silicon intrusion; tungsten-rich silicide on a-Si/quartz produces interfacial voids during high temperature annealing, which initiates crack propagation on cooling.     

Decentralized formation control for small-scale robot teams with anonymity

This paper presents decentralized formation controls for a team of anonymous mobile robots performing a task through cooperation. Robot teams are required to generate and maintain various geometric patterns adapting to environmental changes in many cooperative robotics applications. In particular, all robots must continue to strive toward achieving the team’s mission even if some members fail to perform their role. Toward this end, formation control approaches are proposed under the conditions that robot teams are initially not allowed to have individual identification numbers (IDs), a predetermined leader, and agreement on coordinate systems. Therefore, all members are required first to reach agreement on their coordinate system and obtain unique IDs for role allocations in a self-organizing way. Then, employing IDs within a common coordinate system, two formation control approaches can be realized: leader-referenced and neighbor-referenced formations. Both approaches are verified using an in-house simulator and physical mobile robots. We detail and evaluate each formation control approach, whose common features include self-organization, robustness, and flexibility.     

Development of JARoW-II active robotic walker reflecting pelvic movements while walking

This paper addresses the problem of a novel walking assist scheme considering pelvic movements. Generally, pelvic motion includes pelvic tilt, pelvic rotation, and lateral pelvic displacement. When a human walks, the pelvis is meant to both tilt and rotate. Specifically, rotational movement on the pelvis’ transverse plane and tilting movement on its coronal plane are related to stride length and step width in walking and center-of-gravity swaying in the left-and-right direction, respectively. With these considerations, we introduce the innovative design of our second generation assist robotic walker (JARoW-II) for elderly people in need of supervision. And, this paper proposes a pelvic based walking-support control technique employing JARoW-II. By facilitating pelvic movements while walking, we try to enhance and/or maintain ambulatory performances such as stride length. As another important feature, the scheme is realized without use of specific manual controls or additional equipment. In detail, JARoW-II allows to accurately generate both the direction and location of walking movement and the pelvic movement in a way that corresponds to the user’s walking steps. In this paper, the implementation details based on the walking-support scheme are explained, and the effectiveness of the scheme by using JARoW-II is verified through extensive experiments in everyday environments.