Improving search order for reachability testing in timed automata

Standard algorithms for reachability analysis of timed automata are sensitive to the order in which the transitions of the automata are taken. To tackle this problem, we propose a ranking system and a waiting strategy. This paper discusses the reason why the search order matters and shows how a ranking system and a waiting strategy can be integrated into the standard reachability algorithm to alleviate and prevent the problem respectively. Experiments show that the combination of the two approaches gives optimal search order on standard benchmarks except for one example. This suggests that it should be used instead of the standard BFS algorithm for reachability analysis of timed automata

Assessing a chemosterilant for fertility control of rats

Fertility control of rodents could be used as an additional approach for the sustainable management of pest populations in agricultural production systems. One potential technique is the use of chemosterilants which induce long-term infertility in female animals. The aim of my research was to assess the effects of an industrial chemical, 4-vinylcyclohexene diepoxide (VCD), on reproduction of female and male laboratory rats (Rattus norvegicus). In addition, the uptake of bait types and basic formulations with potential to deliver a fertility control agent to the ricefield rat, Rattus argentiventer, a target species for fertility control in Southeast Asia, was undertaken. In female rats, the effects on ovarian follicle populations were assessed after a period of oral treatment (500 mg VCD/kg/day for 10 days), which was then repeated either once or twice at 14 and 21 day intervals. The effect of three periods of VCD treatment on fertility was examined by mating with fertile, untreated males for 4 breeding cycles. In male rats, the effects of a single 5-day period of oral administration (500 mg VCD/kg/day) on reproductive tissues of juvenile and adult rats were assessed at different times after treatment (days 16 to 90). The effect of VCD treatment on the fertility of adult males was determined by mating with fertile, untreated females for 5 breeding cycles. In the bait-uptake study, laboratory evaluations of bait acceptance by ricefield rats were conducted using different physical forms of bait, vegetable oils, food additives and types of cereal. Based on these laboratory results, the most accepted bait formula plus Rhodamine B (RB) as a bait marker was used under field enclosure conditions to determine the proportion of animals consuming bait and the rate of bait consumption per individual. In females, oral administration of VCD (500 mg/kg) for all treatment schemes induced significant depletion of primordial and primary follicles in the ovaries. Three periods of VCD treatment significantly enhanced ovarian follicle depletion and induced delayed but irreversible infertility. In male rats, a single oral VCD treatment for 15 days did not induce any effects on either reproductive tissues or fertility suggesting an absence of effect on the reproductive status of male rats. Under laboratory conditions, bait in kibble form, containing cereal-base (1O% broken rice, 30% wheat and 30% rice flours), 5% coconut oil, 20% intralipid (a fatty emulsion), and 5% sugar was shown to be most preferred by ricefield rats. Under field enclosure conditions, this bait formula was highly accepted with approximately 90% of ricefield rats consuming bait, and at a high rate per individual (approximately 9.5% body weight). This research has demonstrated that VCD has potential as a candidate for fertility control of rats, and that a cereal-based bait formula derived in this study could potentially be used as a carrier for oral delivery of fertility control agents in ricefield rats. In the future, fertility control could be used as an additional integrated tool for improved management of pest rodents and thus could significantly contribute to food security and poverty alleviation programs in developing countries

A Prototype of Automated Chayote Peeling Machine

Fruit peeling seems a simple performance, but it is the consist of many elements such as the peeler, the way we grasp and move the blade and cutting speed, etc. - all these factors play a role, and interact with each other. This paper describes the prototype of a chayote peeling machine. The machine has been designed with a simple and low-cost approach. To improve chayote peeling rate and ensure pulp quality, a proposed structure was designed, manufactured and tested in laboratory. The experimental results are examined to demonstrate the efficiency of the peeling machine. It proves that the proposed machine could be widely applied in the fruit peeling technology

THE EFL 8TH GRADERS’ ATTITUDES TOWARDS THE USE OF COMPETENCY-BASED INSTRUCTION IN LISTENING COMPREHENSION AT A SECONDARY SCHOOL IN KIEN GIANG, VIETNAM

Listening skill is a vital component of language acquisition on the grounds that it can foster the improvement of other language skills. Therefore, enhancing students’ listening is constantly gaining the prominent attention of most English teachers at secondary schools. Besides, applying competency-based instruction into teaching listening is a novel method that helps teachers attain students’ attitudes, affecting their listening comprehension. Therefore, this current study aimed to examine students’ attitudes toward using competency-based instruction in listening for a main idea and specific information. The study employed a qualitative approach to determine 45 8th graders’ attitudes at a secondary school in Kien Giang province. The students’ diaries were the critical data collection. The study’s findings showed that their views affected their listening skills. Most of them had positive attitudes toward the utilization of competency-based instruction in listening comprehension.  Article visualizations

Interface de contrôle automatisé d’un système de caméras robotisées pour la télétraumatologie

De nos jours, la télémédecine est appliquée universellement dans plusieurs domaines de la médecine comme la radiologie, la pathologie et la psychiatrie. Depuis 2004, le Centre hospitalier universitaire de Sherbrooke (CHUS), la Faculté de médecine et des sciences de la santé et la Faculté de génie de l’Université de Sherbrooke développent un système des caméras robotisées permettant à un traumatologue d’interagir à distance avec un médecin intervenant en salle d’urgence, dans un contexte de télétraumatologie. Ce système demande au traumatologue de contrôler et de positionner les caméras tout en observant l’intervention. Afin qu’il puisse se concentrer le plus possible sur l’intervention chirurgicale au lieu de s’attarder au contrôle du système, une assistance de positionnement des caméras s’avérerait utile. L’objectif de ce projet est de concevoir une interface qui permet de positionner automatiquement les caméras robotisées tout en laissant la possibilité à l’opérateur de les déplacer directement au besoin. Pour ce faire, l’interface de contrôle automatisé utilise des algorithmes de traitement d’images permettant le suivi d’éléments visuels, la détection d’obstructions dans la scène observée et l’approximation de coordonnées tridimensionnelles d’un point dans l’image. Elle exploite deux modes de contrôle : l’opérateur sélectionne une zone d’intérêt directement dans la vue vidéo, ou identifie une région d’intérêt qui est suivie automatiquement par le système, et qui permet au besoin que les deux bras regardent simultanément le dit objet de deux points de vue différents. Avec la détection d’obstructions, l’interface est en mesure de repositionner automatiquement les caméras pour garder la vue sur la zone ou la région d’intérêt. Des tests pré-cliniques menés au Laboratoire de robotique intelligente, interactive et interdisciplinaire de l’Université de Sherbrooke permettent d’évaluer l’efficacité et la pertinence de l’interface de contrôle automatisé. Malgré certaines limitations inhérentes à la rapidité de traitement des commandes de positionnement des caméras intégrées au système, l’analyse des résultats suggère que l’interface de contrôle automatisé est conviviale et diminue la charge cognitive des opérateurs. La performance avec l’interface de contrôle automatisé permettant la sélection de la zone d’intérêt est plus élevée que l’interface de contrôle nonautomatisé (dite manuel, demandant le positionnement manuel des bras robotisés et des caméras), tandis que la performance de l’interface de contrôle automatisé permettant de sélectionner et de suivre une région d’intérêt simultanément par les deux caméras est moins élevée que l’interface de contrôle manuel

Performance of export-oriented small and medium-sized manufacturing enterprises in Viet Nam

The study recommends the formulation of policies that support the development of business linkages and networking, and which promote subcontracting arrangements between small and large enterprises or between domestic firms and foreign investment enterprises. It is also necessary to support and facilitate the direct involvement of SMMEs in exporting or indirectly through large manufacturing enterprises.Export-oriented, SME,SMME, Viet Nam

Integrated Design and Application of Inerter on Vehicle Suspension to Optimal Oscillation

芝浦工業大学201

Why Liveness for Timed Automata Is Hard, and What We Can Do About It

The liveness problem for timed automata asks if a given automaton has a run passing infinitely often through an accepting state. We show that unless P=NP, the liveness problem is more difficult than the reachability problem; more precisely, we exhibit a family of automata for which solving the reachability problem with the standard algorithm is in P but solving the liveness problem is NP-hard. This leads us to revisit the algorithmics for the liveness problem. We propose a notion of a witness for the fact that a timed automaton violates a liveness property. We give an algorithm for computing such a witness and compare it with the existing solutions