Effects of the user model on simulation-based learning of dialogue strategies

Over the past decade, a variety of user models have been proposed for user simulation-based reinforcement-learning of dialogue strategies. However, the strategies learned with these models are rarely evaluated in actual user trials and it remains unclear how the choice of user model affects the quality of the learned strategy. In particular, the degree to which strategies learned with a user model generalise to real user populations has not be investigated. This paper presents a series of experiments that qualitatively and quantitatively examine the effect of the user model on the learned strategy. Our results show that the performance and characteristics of the strategy are in fact highly dependent on the user model. Furthermore, a policy trained with a poor user model may appear to perform well when tested with the same model, but fail when tested with a more sophisticated user model. This raises significant doubts about the current practice of learning and evaluating strategies with the same user model. The paper further investigates a new technique for testing and comparing strategies directly on real human-machine dialogues, thereby avoiding any evaluation bias introduced by the user model. © 2005 IEEE.

Ornamental fish resources of Manipur: potentials, problems and strategies for development

The study revealed 125 species of fishes in Manipur of which 95 species belonging to 48 genera and 22 families have ornamental value. Fifty percent of these belonged to the family Cyprinidae, 7% to Cobitidae, 5% to Sisoridae 7% to Balitoridae, 3% to Channidae, 8% to Bagridae, 2% each to Chandidae and Mastacembelidae. Species representation in other families (16%) includes 1.6% each in Belonidae, Nandidae, Notopteridae, Psilorhynchidae, Schilbeidae and 0.8% each in Amblydpitidae, Anabantidae, Aplocheilidae, Belonidae,Chacidae, Clupeidae, Mugilidae, Symbranchidae, Siluridae and Tetradontidae. The conservation status of fishes showed that 25.6% of them have not been evaluated, 21.6% are vulnerable, 16.0% are endangered and 2.4% are critically endangered. "Low risk near threatened" category amounted to 25.6% and only 6.4% in "low risk least concern" category. Hence a cautious and regulated approach needs to be adopted while promoting ornamental fish trade. Suitable strategies for developing a viable ornamental fish trade in the state are discussed.

Diversification strategies in emerging industries: A supply network perspective

The sustainable translation of scientific and technical innovation into global products and services is key to capturing value from emerging industries. For industrial practitioners, choosing the appropriate entry mode into these industries will often determine their level of success in sharing in this value capture. © 2011 IEEE.

Identification of causes of Thai pangas mortality in ponds and their control strategies

Mass mortality of Thai pangas (Pangasius hypophthalmus) is reported to be a big threat to monoculture of the species in Bangladesh. Twenty affected and twenty control Thai pangas ponds were investigated around Mymensingh district in order to identify the causes of pangas mortality. Sixty affected and sixty unaffected fish samples were examined and compared to find the fish-level variables associated with the disease. A range of haemorrhagic signs on snout, skin and fins were recorded during examination with naked eyes. Aeromonas spp. and Edwardsiella spp. were isolated from 87% and 80% of the affected fish, respectively. Even 4% of the seemingly healthy fish carried Aeromonas spp. on their skin. Among the four water quality parameters monitored, remarkably higher total ammonia (1.5 ppm) was found in water of the affected ponds compared to that of the unaffected ones (0.4 ppm). High ammonia in affected water caused by excessive organic decomposition and poor pond management might have reduced the immunity of fish, which predisposed them for bacterial invasion and consequent disease outbreak.

Threat and management strategies of potentially invasive insects in China

The Global Invasive Species Database, GISD, comprises 27 species of the most significant invasive alien insects in the world (through November, 2005), 6 of which are originally native to China, 11 are established in China, and 10 have a potential invasion

Effect of Co-administration of Morphine and Cholinergic Antagonists on Y-maze Spatial Recognition Memory Retrieval and Locomotor Activity in Mice

吗啡和胆碱能系统的相互作用已在多项研究中提到,本实验想查明吗啡是否能和胆碱能拮抗剂、东莨菪碱以及阿托品共同作用对小鼠的Y迷宫空间识别记忆提取产生影响.采用测试前腹腔给药的方法,选用3种剂量的吗啡(5、1.5、0.5mg/kg),两种剂量的东莨菪碱(1、0.1mg/kg),以及两种剂量的阿托品(0.5、0.1mg/kg),剂量由高到低相配对作为联合给药的手段.其结果表明:1)0.5mg/kg低剂量吗啡与0.1 mg/kg低剂量的东莨菪碱,或与0.1 mg/kg低剂最的阿托品联合给药的小鼠,在记忆提取测试中, 空间探查行为(各臂停留时间百分比)对新异臂没有偏好,而新奇探索行为(各臂访问次数百分比)仍保持了对新异臂的偏好,而相应剂最药物单独给药的小鼠记忆提取均没有被损害;2)吗啡能和东莨菪碱相互作用使小鼠的活动性显著增强.暗示吗啡和胆碱能拮抗剂对小鼠空间记忆提取的破坏存在一定程度的相互作用.

Effect of adrenalectomy and corticosterone replacement on prepulse inhibition and locomotor activity in mice

1 Stress is a risk factor in psychiatric illnesses such as schizophrenia. The aim of the present study was to investigate the effect of different circulating levels of the adrenal steroid corticosterone (CORT) on locomotor hyperactivity and prepulse inhibition of acoustic startle, two behavioural animal models of aspects of schizophrenia. 2 Male C57BL/6J mice (n = 10 per group) were anaesthetised with isoflurane and sham-operated or adrenalectomised (ADX). ADX mice were implanted with 50 mg pellets consisting of 100% cholesterol, or 2, 10 or 50 mg of CORT mixed with cholesterol. CORT pellet implantation dose dependently increased plasma CORT levels 3 weeks after surgery. Starting 1 week after surgery, mice were tested for prepulse inhibition after injection of saline or 5 mg kg(-1) of haloperidol. 3 In intact mice and in mice implanted with 10 mg of CORT, haloperidol treatment significantly increased prepulse inhibition (average values from 38 - 42 to 52%). Similar results were observed when testing the mice for amphetamine-induced locomotor hyperactivity (5 mg kg(-1)). In contrast, there was no significant effect of haloperidol in mice implanted either with cholesterol or 2 or 50 mg of CORT. 4 These results in behavioural animal models of schizophrenia suggest an important role of the stress hormone CORT in modulating dopaminergic activity in this illness.

Strategies for sustainable use of living aquatic resources

Recommendations of the Department of Environment and Natural Resources (Philippines) to conserve biodiversity, maintain the integrity of the environment, protect fishery stocks, involve fishing communities in the management, and use environment-friendly technologies for enhancing fishery production.