Research on the Key Technologies of Network Security-Oriented Situation Prediction

In today’s increasingly severe network security situation, network security situational awareness provides a more comprehensive and feasible new idea for the inadequacy of various single solutions and is currently a research hotspot in the field of network security. At present, there are still gaps or room for improvement in network security situational awareness in terms of model scheme improvement, comprehensive and integrated consideration, algorithm design optimization, etc. A lot of scientific research investments and results are still needed to improve the form of network security in a long and solid way. In this paper, we propose a network security posture assessment model based on time-varying evidence theory for the existing multisource information fusion technology that lacks consideration of the problem of threat occurrence support rate over time and make the threat information reflect the law of time change by introducing a time parameter in the basic probability assignment value. Thus, the existing hierarchical threat posture quantitative assessment technique is improved and a hierarchical multisource network security threat posture assessment model based on time-varying evidence theory is proposed. Finally, the superiority of the proposed model is verified through experiments.

Some Soical Postures of Five Species of Rattus

Adult male wild rats of the species Rattus norvegicus, R. rattus, R. villosissimus, R. fuscipes and R. lutreolus have been observed during encounters in large cages designed for observation and photography. In each encounter one male was a resident; the other an intruder of the same species. The postures and patterns of movement adopted during encounters are described and illustrated. Details of some interactions are given. Methods of maintenance are described. Behaviour patterns which are probably apotreptic (tend to cause withdrawal by a conspecific) include an arched back 'threat posture', and attack (leap occasionally accompanied by biting). Among probable epitreptic acts. (those that encourage approach or inhibit attack) are crawling under or over another rat. Allogrooming appears to be sometimes apotreptic, sometimes epitreptic. There is, however, little quantitative evidence on these apparent signals. A complete display, or pattern of social signals, probably includes sounds, odours, and tactile stimuli, as well as visible postures. Proposals are made on the names and classification of the postures. The actual or hypothetical roles of the various signals are reviewed.

The tortoise and the rail

Giant tortoises ( Geochelone gigantea ) on Aldabra respond to light tactile stimulation of their soft posterior regions by adopting an immobile erect stance, previously thought to be a threat posture. It is argued that this is probably a cooperative posture assisting any potential symbiont to clean ectoparasites from the areas of soft skin thus exposed. Most Aldabran tortoises over 25 cm long respond in this way and the response appears to be unaffected by activity, sex, time of day and ectoparasite abundance. The visual stimulus of a white-throated rail Dryolimnas cuvieri within 1 m may also elicit this response, and rails were observed removing ectoparasites from tortoises which had adopted the cooperative posture. The distributions of the tortoise and the rail overlap only slightly and the mutualism is thought to be ecologically unimportant to both the ectoparasites and the rail. Comparisons are made with the mutualism involving Galapagos giant tortoises, Geochelone elephantopus , and the ground finches Geospiza fuliginosa and G.fortis ,and the mockingbird, Nesomimus parvulus .

Ontogeny of the Orienting-Jump Response of the Rabbit

The ontogeny of a defensive-threat posture of the adult rabbit, designated the orienting-jump response, was studied in New Zealand white rabbits from birth by stimulating one side of the body with a blunt probe. A number of components of this response were found to develop at different rates postnatally: oriented jump towards side of stimulation; hind limb thrust; vocalization; fore-limb stab; bite-attack; directed escape; striking ground with hind-limb (appel). It was shown therefore, that several components become incorporated during ontogeny into a complex species-specific response, which might, in the absence of ontogenetic evidence, be thought to be a simple fixed action pattern. It is hypothesized that the tendency to escape from and to orient towards a noxious stimulus (such as a predator) might contribute to the erratic zig-zag escape pattern in this species.

Behavioural Effects of Electrical Stimulation in the Forebrain of the Pigeon Ii. Protective Behaviour

Responses that showed a very good conformity to the normal defence and escape behaviour have been released by means of electrical stimulation at di- and telencephalic structures in the forebrain in unanaesthetized, freely moving pigeons (Columba livia). The defense response consisted of the characteristic threat posture of the species with crouching, ruffling of the feathers, wing erection and the growling vocalisation. The response could be very intense with defensive attacks, either in empty space or towards a threatening object. The attacks were accompanied by a short and hard call. The escape response was shown either by flying or running away. The defence and escape responses were obtained from a linked substratum extending from the hypothalamus and the diencephalic paraventricular gray via the area ventralis and the posterior parts of the cerebral peduncles up into the paleo- and archistriatum. The defence reactions were released from more medial sites compared to the escape reactions. The spatial arrangement of the active area within the forebrain shows similarities with the neural projection of the same category of behaviour in mammals. Combined data from this and a previous investigation show that a field involved in the coordination of an "agonistic" behaviour complex including aggressive and defensive threat and escape can be traced in the di- and telencephalon of the pigeon. The results produce further evidence that functionally linked actions at a high level also have a linked central representation.

Observations On the Incidence of Following of Visual and Auditory Stimuli in Naive Mallard Ducklings (Anas Platyrhynchos)

The responses of naive mallard ducklings to simple moving models and to simple calls (rapidly repeated "kom") were studied at different posthatch ages, ranging from 3 to 240 hours. i. The proportion of ducklings following moving models, not accompanied by calls, gradually decreased from 58 % at io-20 hours to 17 % at 240 hours. 2. The proportion of ducklings responding to moving models by avoidance rose steeply with increasing age, beginning with 46% at I0-20 hours and reaching ioo% at 240 hours, or probably earlier, between 80 and 240 hours. 3. The proportion of ducklings ready to follow auditory stimuli showed a steep initial rise, culminating in a maximum of 85% reached at 40-5o hours, and followed by a final decrease, although not so marked as in the case of visual stimuli. At 240 hours, the proportion of followers was still as high as 50 %. 4. Ducklings which had not initially followed moving objects could be induced to do so by presenting the model in combination with auditory stimuli. After this procedure, they followed the model even when no auditory stimuli were presented. 5. Some ducklings reacted to moving models by aggressive behaviour (threat posture and attack), or by pumping head movements similar to the pre-copulatory display of the adult mallard. 6. The discrepancy between the long persistence of the following tendency in naive ducklings and the existence of an early critical period found by HESS is discussed. It is suggested that the departure of mallard ducklings from the nest often takes place at an age well past the critical period. Under these circumstances the long persistence of a high level of responsiveness to stimuli releasing the following reaction must have a high adaptive value, particularly in connection with the dangerous journey of the brood from the nest to the nearerst water. The curve for the following of auditory stimuli probably reflects the true state of the following tendency more closely than the curve for the following of visual stimuli, which is depressed by escape tendencies in older ducklings. Ignorance of the long persistence of the responsiveness to unconditioned stimuli eliciting the following response may have been a source of error in some current work on imprinting.