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When it comes to robotic agents operating in an uncertain world, a major concern in knowledge representation is to better relate high-level logical accounts of beliefs and actions to the low-level probabilistic sensorimotor data. Perhaps the most general formalism for dealing with degrees of belief in formulas, and in particular, with how that should evolve in the presence of noisy sensing and acting is the first-order logical account by Bacchus, Halpern, and Levesque. The main advantage of such a logical account is that it allows a specification of beliefs that can be partial or incomplete, in keeping with whatever information is available about the domain, making it particularly attractive for general-purpose cognitive robotics. Recently, this model was extended to handle continuous probability distributions. However, it is limited to finitely many nullary fluents and defines beliefs and integration axiomatically, the latter making semantic proofs about beliefs and meta-beliefs difficult. In this paper, we revisit the continuous model and cast it in a modal language. We will go beyond nullary fluents and allow fluents of arbitrary arity as is usual in the standard situation calculus. This necessitates a new and general treatment of probabilities on possible worlds, where we define measures on uncountably many worlds that interpret infinitely many fluents. We then show how this leads to a fairly simple definition of knowing, degrees of belief, and onlyknowing. Properties thereof will also be analyzed. In this paper, we focus on the static setting and conclude with some thoughts about extending this account to actions as the next step and what challenges might arise.

This article proposes a network security protection scheme for power system embedded devices based on chip-level trusted computing, gives the overall architecture of power equipment chip-level trusted computing, introduces the principle of trust chain transfer within power terminals, and proposes the method of using the on-chip SRAM inside the main control chip of power system embedded devices as the PUF to construct the trusted root. Furthermore, we propose a complete trust transfer mechanism from booting trust to the loading that trust on operating system and application, and give the corresponding program design framework and program logic. The chip-level trusted computing program designed in this article was applied in a distribution automation DTU device equipped with the FUXI chip that is developed by the China Southern Power Grid and the Sylix OS operating system. Finally, we carry out the security protection test. The validity of the designed program is verified by running malicious programs to attack the power equipment. The results show that the designed program can effectively detect and intercept illegal programs, and provide an effective solution for the security protection of power equipment in the open network environment.

Cys-loop receptors are ligand-gated ion channels that play a significant role in the central nervous system regulating numerous central nervous diseases. Members of the Cys-loop receptor family include nicotinic acetylcholine (nACh), γ-amino butyric acid (GABAA), 5-hydroxytryptamine(5-HT3) and glycine (Gly) receptors. These receptors share an overall similar structure and mode of action. As targets for drugs, these receptors modulate and relieve symptoms of diseases including epilepsy and Alzheimer’s Disease. AM-3607 and AM-1488 are two modulators of Glycine receptors (GlyRs) that were reported recently by Amgen. Structural studies and co-crystallisation with the human α3 GlyR identified these compounds as belonging to a novel class of positive allosteric modulators (PAMs) with a binding site not previously reported in any Cys-loop receptor. The compounds bind to a pocket just above the glycine binding pocket from where they enhance the binding affinity and potency of glycine. In the present project we aimed to investigate if a site in a similar position in other Cys-loop receptors also could act as a PAM site. Overall, this thesis aims to identify the existence of this binding site on other Cys-loop receptors. To achieve this, the 3D structure of AM-3607 co-crystallised with human α3 glycine receptor was analysed to identify residues lining the binding site. Subsequently, corresponding residues in all other Cys-loop receptor subunits were identified based on a sequence and protein structure alignment to identify the subunits and subtype most similar to the glycine α3 subunit. Together with considerations regarding common existence and ease of handling in pharmacological experiments, the α1β2 GABAA receptor was selected for further studies. A total of 6 residues were then mutated to introduce a binding site on α1β2 GABAA receptor similar to the AM-3607 binding site on the glycine receptor. In an alternative attempt, due to a structural difference result from the different length of a Tyr78 containing loop connecting two β strands, a chimeric α1 GABAA receptor was prepared incorporating the loop from the glycine receptor. The effect of mutant and chimeric receptors was subsequently evaluated with GABA and GABA in combination with AM-1488 using two-electrode voltage clamp electrophysiology. The concentration response curves revealed EC50 values for (α1)3(β2)2 and (α1)2(β2)3 GABAA receptors of 2.59 μM and 1.08 μM in agreement with literature values. Mutant receptors, GABAA (α1M)3(β2)2, (α1M)2(β2)3, (α1)3(β2M)2, (α1M)3(β2M)2, (α1M)2(β2M)3 and chimeric receptors (α1C)3(β2M)2 and (α1C)2(β2M)3 showed EC50 values of 0.65 mM, 0.65 mM, 11.8 μM, 3.38 mM, 5.60 mM, 0.62 mM, 0.92 mM, respectively. For all constructs involving mutant β2 subunit, potency was significantly impaired compared to wild type receptors. Further, none of the constructs were potentiated when AM-1488 was co-applied with GABA. This research identified that AM-1488 had no potentiating effect on the mutated GABAA receptors but in most cases, mutations affected the potency and efficacy of GABA. Despite the negative results, evaluation of the mutant receptors showed that residues in the area corresponding to the AM-1488 pocket had great effect on GABA potency and efficacy and it cannot be excluded that the site has modulatory properties in wild type receptors if a complementary molecule to fit the pocket can be identified.

Based on the intelligent organism through a variety of sensory information to identify the object's cross-modal perception, this paper proposes a kind of cross-over model based on multi sensor information fusion robot taste 1 recognition strategy that formally introduces subjective judgment and intuition into statistical inference and decision analysis so as to establish the basis for synthesis information inference and decision analysis process. This strategy can be based on the uncertainty information of multi sensor, the problem of incomplete representation of single sensor information is solved to achieve the purpose of taste recognition. In the simulation experiment, when using the initiative olfactory of the robot to search for and judgment the odor source, the smell and visual information are used to identify the suspected odor source quickly and effectively through the cross-over model taste recognition strategy, which proves the effectiveness of the strategy.

In this paper, a robot bionic odor source localization algorithm based on kinesis response and tropotaxis behavior of flatworm is proposed, the algorithm does not need to detect wind direction information and odor absolute concentration information. Experiments show that the proposed algorithm is not affected by both wind direction and wind speed, only by judging the rate of change of odor concentration, which improves the searching efficiency, has good stability and environmental adaptability. it is a reliable initiative olfactory strategy with simple, search speed, high efficiency advantages.