Controller design and performance evaluation for deadlock avoidance in automated flexible manufacturing cells

In this paper, the design of a deadlock avoidance controller is described. The uncontrolled system is modeled using colored Petri nets. The system controller is based on a restrictive (not maximally permissive) deadlock avoidance policy to resolve deadlocks and control the real-time resource allocation decisions in the system. Performance evaluation of systems controlled by not maximally permissive algorithms is essential in determining the applicability and effectiveness of the control algorithms. The performance of the controlled system is compared with performance of optimal control policies to quantify the effects of the restrictiveness of the deadlock avoidance policy on system performance.     

Fuzzy-Logic Based Navigation of Underwater Vehicles

A fuzzy logic based general purpose modular control architecture is presented for underwater vehicle autonomous navigation, control and collision avoidance. Three levels of fuzzy controllers comprising the sensor fusion module, the collision avoidance module and the motion control module are derived and implemented. No assumption is made on the specific underwater vehicle type, on the amount of a priori knowledge of the 3-D undersea environment or on static and dynamic obstacle size and velocity. The derived controllers account for vehicle position accuracy and vertical stability in the presence of ocean currents and constraints imposed by the roll motion. The main advantage of the proposed navigation control architecture is its simplicity, modularity, expandability and applicability to any type of autonomous or semi-autonomous underwater vehicles. Extensive simulation studies are performed on the NPS Phoenix vehicle whose dynamics have been modified to account for roll stability.     

汽车防撞雷达系统滤波器的设计

针对调频连续波 (FMCW)汽车防撞雷达实际信号的特点 ,设计了一种用于该汽车防撞雷达有用信号提取的系统滤波器 ,分析了其前级宽带模拟带通滤波器和后级数字信号处理器 (DSP)程控自适应滤波器的设计原理与具体实现 .试验数据表明 ,该系统滤波器可以有效的去除干扰并实现有用信号的精确提取     

Amygdala Inactivation Blocks Expression of Conditioned Memory Modulation and the Promotion of Avoidance and Freezing.

Rats were exposed to shock-paired cues immediately after training on an appetitive preference task. Elevated levels of freezing in and active avoidance of the shock-paired compartment were observed, and memory for the appetitive task was improved when tested 24 hr later. Intra-amygdala muscimol injected before the posttraining exposure eliminated freezing, avoidance, and memory modulation. The blockade of both freezing and active avoidance, which involve competing behavioral tendencies, makes it unlikely that the amygdala itself generates either behavior. The elimination of conditioned memory modulation suggests that conditioned neurohormonal responses were blocked. These conditioned internal responses may comprise the intervening variable of "conditioned fear" and may promote observable behaviors, the form of which is determined by the environment in which they occur. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Forgiveness and Conflict Resolution in Marriage.

Two studies examined whether forgiveness in married couples is associated with better conflict resolution. Study 1 examined couples in their 3rd year of marriage and identified 2 forgiveness dimensions (retaliation and benevolence). Husbands' retaliatory motivation was a significant predictor of poorer wife-reported conflict resolution, whereas wives' benevolence motivation predicted husbands' reports of better conflict resolution. Examining longer term marriages, Study 2 identified three forgiveness dimensions (retaliation, avoidance and benevolence). Whereas wives' benevolence again predicted better conflict resolution, husbands' avoidance predicted wives' reports of poorer conflict resolution. All findings were independent of both spouses' marital satisfaction. The findings are discussed in terms of the importance of forgiveness for marital conflict and its implications for spouse goals. Future research directions on forgiveness are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

'It's the end of the world as we know it': Threat and the spatial-symbolic self": Correction to Burris and Rempel (2004).

Reports an error in 'It's the End of the World as We Know It': Threat and the Spatial-Symbolic Self" by Christopher T. Burris and John K. Rempel (Journal of Personality and Social Psychology, 2004[Jan], Vol 86[1], 19-42). The article contained two errors. On page 35, second column, line 14, two of the word fragments are notated incorrectly. The word shown as s[k]ull should be sk[u]ll, and the word shown as as[h]es should be as[h]e[s]. (The following abstract of the original article appeared in record 2003-11198-002.) According to amoebic self theory, the boundary defining the self encompasses 3 levels of self-representation--bodily, social, and spatial-symbolic. Study 1 related a newly developed measure of individual differences in sensitivity to boundary threat across these 3 domains to values and disgust sensitivity. Four subsequent studies focused on spatial-symbolic threat sensitivity and related it to right-wing authoritarianism, aversive reactions to unfamiliar out-groups, and revulsion to vermin. A final experiment illustrates how a salient spatial-symbolic threat (dust mites) can elicit reactions toward out-groups that closely parallel mortality salience effects observed in research inspired by terror management theory, even though dust mites do not elicit mortality concerns. The importance of preserving the familiar in order to preserve the self is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Drivers’ eye movements as a function of collision avoidance warning conditions in red light running scenarios

The intersection collision avoidance warning systems (ICAWSs) have substantial potentials in improving driving performance and reducing the number and severity of intersection collisions, through helping drivers timely detect hazardous conflicting vehicles in precrash scenarios. However, the influences of ICAWS on drivers’ visual performance have barely been discussed. This study focuses on exploring the patterns in drivers’ eye movements as a function of ICAWS’s warning conditions in red light running scenarios based on a driving simulation experiment. Two types of speech warning conditions including warning timings (varied form 2.5 s to 5.5 s) and directional information (with or without) are examined, and the no-warning condition is the baseline. The results revealed that more subjects would be likely to benefit from the ICWAS under the earlier warning timings. The warning condition of 4.5 s ahead of a collision had the best effectiveness in terms of visual performances. Under such a warning timing, drivers had shorter fixation duration and higher frequency of searching for the red light running (RLR) vehicles. Compared to the warning condition without directional information, the directional warning information could capture drivers’ attention more efficiently, help driver direct fixations toward the RLR vehicles more quickly and lead to more scanning activities. Compared to female drivers, male drivers had more scanning activities when approaching intersections, detected the RLR vehicles more quickly and were more likely to avoid the RLR collisions. Besides, the experiment results indicated that the female drivers were more inclined to trust the warning information and got more benefits from the RLR-ICAWS in terms of the crash risk reduction rate than male drivers. Finally, the conclusions lead the way toward warning condition design recommendations for improving the effectiveness of the RLR-ICAWSs.     

An algorithm for multi-robot collision-free navigation based on shortest distance

This paper presents a new approach for multi-robot navigation in dynamic environments, called the shortest distance algorithm. This approach uses both the current position and orientation of other robots to compute the collision free trajectory. The algorithm suggested in this paper is based on the concept of reciprocal orientation that guarantees smooth trajectories and collision free paths. All the robots move either in a straight line or in a circular arc using the Bresenham algorithms. The current approach is tested on three simulation scenarios.     

The effects of SNS communication: How expressing and receiving information predict MERS-preventive behavioral intentions in South Korea

Individuals use social network sites (SNSs) as an effective tool for communicating relevant information with others during the outbreak of infectious diseases. However, little is known about the underlying mechanism through which communicative behaviors influence preventive behaviors. Thus, in the context of Middle East respiratory syndrome (MERS) in South Korea, this study investigated how two communicative behaviors (message expression and reception) in SNSs affected the communicators’ intentions to engage in MERS-preventive behaviors. Using data collected from a nationally representative panel survey of 1000 Korean adults aged 19 or older, we examined a theoretical expression and reception effects model. Results support the presence of effects from expressing and receiving MERS-related information via SNSs and their underlying mechanism during South Korea’s MERS outbreak. Public health officials and communication professionals should actively use SNS communication in coping with public health crisis caused by emerging infectious diseases.     

Who avoids location-based advertising and why? Investigating the relationship between user perceptions and advertising avoidance

This study investigates how perceptual factors are associated with mobile consumers’ avoidance of location-based mobile advertising (LBA), and whether the relationships between the perceptual factors and LBA avoidance are influenced by consumers’ mobile device usage levels. The results of a national web survey with 605 Singaporean mobile consumers show that those who find LBA impedes goals, requires sacrifice, and lacks utility are more likely to avoid it. When examining the differences of heavy, medium, and light mobile device users, the analyses reveal that the effects of perceived utility and entertainment on LBA avoidance are greater for medium and heavy users than for light users. Theoretical and practical implications of our findings are discussed, as are the limitations and suggestions for future research.