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Information service is always a hot topic especially when the Web is accessible anywhere. In university, lecture information is very important for students and teachers who want to take part in academic meetings. Therefore, lecture news extraction is an important and imperative task. Many open information extraction methods have been proposed, but due to the high heterogeneity of websites, this task is still a challenge. In this paper, we propose a method based on fusing multiple features to locate lecture news on the university website. These features include the linked relationship between parent webpage and child webpages, the visual similarity, and the semantics of webpages. Additionally, this paper provides an information service based on a main content extraction algorithm for extracting the lecture information. Stable and invariant features enable the proposed method to adapt to various kinds of campus websites. The experiments conducted on 50 websites show the effectiveness and efficiency of the provided service.

Lower back pain accounts for more than half of all reported on-the-job ailments, escalating from a personal challenge to a broader societal challenge. Researchers have developed a power assist suit intended prototype to reduce the incidence of lower back pain in the workplace when process automation is not possible. Equipped with two pneumatic actuators, the prototype suit is lightweight, flexible, and efficient. The prototype suit can assist human motion using passive and active forces. In this study, researchers confirmed the effectiveness of passive assistive force. Two types of motion were considered: lifting and unloading in a crouching position and carrying. Researchers first analyzed the subject motions using video analysis software. Waist joint loads were estimated using motion analysis results and a human link model. Second, researchers determined the power assist suit's operational parameters and developed a power assist suit model. Lastly, researchers confirmed the passive force prototype suit's effectiveness based on measured changes in generated force and electromyography.

The most important benefits of flexible link manipulator include high payload-to-arm weight ratio. The reduction of weight leads to increase of the link elasticity that significantly complicates the control of the manipulator. The difficulty in control is caused by the fact that the link model is a distributed parameter plant. In this case, several elastic modes are required to achieve sufficiently high accuracy. Plus, the plant has several uncertain parameters (payload mass, hub and structural damping factors, etc.) that influence the systems performance. In this paper, Trajectory Tracking Controller is suggested by utilizing the hybrid controller approach to overcome the problem of vibration of tip position through motion which is a characteristic of the flexible link system. A modified version of the proportional-derivative rigid controller to track the hub position while sliding mode control was used for vibration damping. Also, a second controller (a fuzzy logic based proportional integral plus derivative control scheme was developed for both vibration damping and trajectory tracking. Results are illustrated in the robust performance of the proposed tip position tracking controllers over the payload variation. A good performance is obtained for the trajectory tracking. The stability of these controllers is also proved.

Gyroscope is well known as a sensor but also used as an actuator. In the beginning of 20th century, research that related with gyro-monorail by using a gyro-actuator was conducted. Later, the research on a gyro-bike system was reported in 1970's. Then, the self-sustaining body bike has been reported up until now. In this paper, we propose an unmanned self-sustaining driving control bike in a straight motion using gyro-actuator which is controlled by a computer. First, we use the link model to construct the linear equation of motion. Next, we develop the modeling of a gyro bike system by using the link model theory. Then, we conduct the experiments to confirm the result of the theory.

Spreading sequences are usually allocated to users irrespective of their channel conditions. In this paper we allocate sequences based on their channel conditions to improve the performance of the link model. We also propose an analytical model for the allocation scheme. We validate the analytical model on a down-link and evaluate its performance, to show an increased gain in the performance of the down-link model.

One of the issues with the use of satellite communications (SATCOM) in tactical networks is the disconnection between the planning and management of the satellite networks and the network operations including planning and management of the deployed tactical network. This paper attempts to bridge this gap, addressing how the router interface connected to a satellite terminal can be configured to optimize the use of the satellite resources. Tactical networking community stakeholders have suggested the weighted random early detection (WRED) as a means to provide functional capabilities for the military precedence-based assured service (PBAS). This paper argues that WRED configurations is not “one size fits it all”, thus derives formulas and procedures to analyze the WRED performances for various configurations. The paper presents a reference WRED design in application to optimizing the tactical SATCOM resources. For the SATCOM link model given, formulas and procedures to analyze the packet drop and delay characteristics are derived to help engineers to carry out the network performance analyses for various WRED configurations. Impact of packet buffer size on the network performances is investigated to provide a knowledge base for the WRED design. The applicable ranges of the WRED configuration parameters and their impact on performance variations are investigated to help understand and design the WRED. A reference WRED configuration is presented to guide the WRED design for the tactical SATCOM network. The thought process to establish the reference configuration is also given to help understand the reasoning behind the design procedures. The results on packet drop and delay characteristics obtained for various WRED configurations show that the presented analysis method is applicable to the WRED performance analysis and design for the tactical SATCOM.

In order to avoid machine related catastrophes, the early detection of cracks is in urgent demand. Sensors are put into the rotating parts of machine and vibration signal data are collected to diagnose machine health. This paper proposes a comprehensive method to look into the development of damage with multinomial logit model (MLM) and cumulative link model (CLM). We first select features according to analysis of variance (ANOVA), and then compare the MLM, CLM method with weighted k-nearest neighbor method (WKNN) — a black box machine learning algorithm and we conclude that these methods have their pros and cons in the diagnosis of faults.

In this paper we study a model of joint congestion control and routing in a ring network of sources with a single destination at the center (Figure 2). A utility maximization problem subject to routing constraints is posed and equations for its solution are presented. The distribution of traffic on routes available to a source is subject to an entropy constraint that controls the path diversity or degree of robustness of the allocation. Thus the utility/stability issue can be addressed directly and quantitatively in a way that differs from previous work on multiroute NUM problems. The dynamics of the model equations will be analyzed in the case of a constant route allocation defined by the allocation distribution entropy for a source. Motivated by earlier work on a two link network, the dynamics of the mean route costs for each source in the ring network are studied by deriving a continuous time approximation of the equations they satisfy. The equilibrium solutions of this approximation are used to greatly simplify the analysis of the model equations and the solution of the original optimization problem. We conclude with a discussion of the tradeoff between utility and path diversity (robustness) for two contrasting assignment of link capacities. Given a homogeneous assignment of capacities the network behaves like a two link model (Fig 1), while a heterogeneous assignment produces utilities displaying different tradeoffs for different sources.

This paper suggests a novel reaction force control design of two-link manipulators based on a bi-articular driving system. Considering muscles' viscoelasticity, the animal link model can control its reaction force against ground surface using a position feedback without a force feedback. To verify this characteristic, we explain the model of muscle and the animal link model. And then, the analogy between the force generating mechanism of muscle and a two degrees of freedom control is shown, and the intrinsic reaction force control of bi-articular driving system based on a position feedback is suggested. Finally, simulation results ensure this characteristic

Quantitative diagnosis of the knee joint dynamics is required to decrease the inner- and intra-observer variability. This paper proposes a noninvasive, unconstrained and free field of measurement system of 3 degree-of-freedom knee joint angles. The proposed system employs a compound sensor of inertial and magnetic sensors. Based on a rigid-body link model, the proposed method enables a measurement system. The experimental results showed that the proposed method estimated the flexion of knee joint angle with a mean displacement of 1.3 deg.

A behavioral, nonlinear radio-over-fiber (RoF) link model considering memory effects with low complexity is presented. Model validation against experimental results is demonstrated, with the effect of the memory length on the fitting accuracy being studied.

Network-in-the-loop is the direction that the military training simulation is advancing forward. Dynamic networking modeling is the key issue for constructing the network-in-the-loop training simulation. For this purpose, the fundamental architecture for the network-in-the-loop training simulation was analyzed and presented. Several features of dynamic networking modeling were researched. Based on a general view of the network, a set of networking models suitable for the network-in-the-loop training simulation were constructed, including the aggregated vehicle node model and latent link model. Now, these models are working well in a certain training simulation.

As aging progresses, fall accident of the person using the walker is an acute problem. It is necessary to know the situation of the userpsilas fall to prevent it. In this paper, we propose a method for estimating the userpsilas fall by modeling of the user in real time as a solid body link model, and pay attention to the center of gravity of the model. We also propose a method for controlling a passive intelligent walker to prevent the userpsilas fall according to the support polygon and the walking characteristic of the user. We experimented with passive intelligent walker in which we implement the proposed fall prevention control and show the effectiveness of the proposal method.

This paper describes an instruction assist system for instruction of Taijiquan in Intelligent Space. Taijiquan is a Chinese physical exercise whose practice is believed to be beneficial for maintaining one's health. The instruction system provides learners with two pieces of functionality. The first measures the position and posture of the learner and simultaneously displays the measurement results as a 3-dimensional computer graphics human model with expert's one measured in preliminary experiments. The measurement is performed with arrays of optical and ultrasonic sensors installed in the space. The second monitors load on knees of the learner, which is estimated with the measurement results and a load model, in order to avoid knee injuries which may occur in the practice. The load model is developed based on a human body link model and the measurement of electromyographic (EMG) signals from the muscles on thigh whereas the monitoring method doesn't need measurement of EMG signals in run time.

Presented herein are the time-domain simulation results for a multi-Gb/s I/O channel using three different modeling and simulation approaches. Time-domain simulation results based on a converted S-parameter model, segmented RLGC models, and a VNA extracted end-to-end channel measurement based model.

A new method for identifying rigid link models of human lower limbs has been proposed in this paper. The method was motivated by necessity of simulating human body movements for rehabilitation or for design of assistive devices. The method is based on combination of random search and least squares estimation techniques. Simulation and experimental results are given to illustrate the effectiveness of the proposed method.

In this paper, an elastic graph dynamic link model (EGDLM) is proposed to automate the satellite interpretation process (Dvorak technique) and provide an objective analysis for tropical cyclones. The method integrates dynamic link architecture (DLA) for neural dynamics and the active contour model (ACM) for contour extraction of tropical cyclone (TC) patterns. Using satellite pictures provided by National Oceanic and Atmospheric Administration (NOAA), 145 tropical cyclone cases from the period between 1990 to 1998 were extracted for the study. An overall correct rate for TC classification was found to be above 95%. For hurricanes with distinct "eye" formation, the model reported a deviation within 3 km from the "actual eye" location, which was obtained from the aircraft measurement of minimum surface pressure by reconnaissance.

Pulsed UWB (ultra wide band) signals are more nearly transient phenomena than they are continuous waves. Multipath effects for the most part manifest themselves as time delayed replicants of the pulses. Short pulses propagate with the free space law, and only when the differential delay among pulses and replicants is less than about half the pulse length do the signals exhibit destructive interference. The propagation model described here is based on the free space law with the additional effect of transmission losses through typical home or office walls. The conditions for destructive inference of pulses is also derived.

Soft handoff has a special importance to power controlled code division multiple access (CDMA) systems. We introduce a new analytical model for CDMA soft handoff with emphasis on interference statistics at a system level. The relationship between soft handoff and power control is further explored by integrating power control error and shadowing correlation into the model. A new forward link model is also devised to study the effects of soft handoff on forward link performance. It is observed that the performance degradation due to power control error increases with increase in soft handoff region and higher shadowing correlation lowers the interference contribution from nonhandoff mobile stations (MS). It is also found that, unlike the reverse link, the forward performance depends on both given soft handoff setting and system load.

This paper evaluates the controlled plane motions of elastic manipulator with electrodrives. The dynamics of rotary motions of the last link of manipulator is considered within the framework of elastic beam model. Time-optimal control of rigid link system is considered taking into account electromagnetic processes in electrodrives. Different rational control functions are investigated. These rational control functions are implemented in elastic link model. Evaluation of accuracy and amplitude of residual vibration is done. Methods of increase of operational accuracy are considered.

A new model for the dynamics of a rigid link robotic arm that is readily extendable to a flexible link model is developed. The corresponding flexible link model is the developed. A procedure is presented for extending the new rigid link model to the corresponding flexible link model.

The presence of force feedback in medical instruments has been proven to reduce tissue damage. In order to provide force feedback, information about the interaction forces between the instrument and the environment must be known. Direct measurement of these forces by commercial sensors is not feasible due to space limitations. Thus, in this study we propose to estimate the interaction forces using strain measurements from Fiber Bragg Grating (FBG) sensors. These measurements can also be used for shape sensing and as a result both force and shape can be sensed simultaneously. For force sensing two models are proposed and compared. The first is based on a Rigid Link approximation, while the second uses the Cosserat rod theory. The models are validated experimentally using a tendon-driven continuum manipulator that is subjected to forces at the tip. The force estimates from the models are compared to the measurements from a commercial force sensor. Mean absolute errors of 11.2 mN (6.9%) and 15.9 mN (8.3%) are observed for the Rigid Link model and Cosserat model, respectively.