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Using the complex stratigraphic structure model, we study the changes in remaining oil on the millimeter scale in different structural parts during the different water flooding development methods. According to the actual geological structure characteristics of the oil layer, We designed and produced the meter-level experimental model, which ensures the similarity between the model structure and actual oil layer structure. The recovery rate of the primary water flooding stage is 10.36%. The stage recovery rate addition of the change flow direction stage is 7.85%. The final recovery rate is 41.36%. The physical interlayer structure has an influence on the oil saturation change in the nearby layers. The oil saturation reduction value is highest in the left part of layer 3 in the primary water flooding stage, the reduction range is 24.81%. There are 2 parts and 1 part where the oil saturation decreases by more than 10.0% in the second boost flooding stage and the change flow direction stage, respectively.

The article of record as published may be found at https://doi.org/10.1002/bmc.4478 Isaria cicadae is one of the fungi used in traditional Chinese medicine with the longest tradition. It is used not only as a herbal medicine but also as a health food in Asia, together with cultured cordyceps and mycelia of the fungus used as substitute. However, the differences in their metabolite are unknown. Using a high‐performance liquid chromatography–mass spectrometry (HPLC–MS)‐based metabolomic method, we found that the fungus varies in its metabolism during growth on wild insects, artificially raised insects and artificial medium. There were 109 discriminatory metabolites detected in the samples by orthogonal projection to latent structure discriminant analysis and one‐way ANOVA. High level of nonribosomal peptides (NRPs) only existed in the insect portions of the wild cordyceps (WI) and cultured cordyceps (CI), revealing that immunostimulation of the host insects enhanced the synthesis of NRPs in the fungus. The finding of a signifi- cantly higher level of sphingolipids in both the insect portions (WI, CI) and the coremia of the wild cordyceps (WC) and cultured cordyceps (CC) but not in cultured mycelia (CM) of I. cicadae implies that the immunostimulation of the live insects can induce the fungus to produce more sphingolipids, and this enhanced ability is probably heritable. Apart from NRPs and sphingolipids, the insect portions also contained higher levels of bioactive compounds such as lateritin, anisomycin, streptimidone and ustiloxins. In contrast, the coremium groups (WC, CC) and CM contained 10‐fold less NRP but much higher levels of sanative metabolites such as tocotrienol, 3′‐deoxy‐ hanasanagin, γ‐aminobutyric acid and phospholipids than the insect portions. The significantly higher content of antioxidants in WC, CC and CM than in WI and CI suggests that environmental oxygen has a significant effect on the metabolites. The temperature stress which the wild cordyceps encounters during growth is responsible for the relatively high content of trehalose. These findings indicate that the immunity of the host insect and growth environment have a strong impact on the metabolomic variation in Isaria cicadae. The variation in metabolites suggests differential utilization value for the insect portions, coremia and mycelia of the fungus. National Natural Science Foundation of China, Grant/Award Numbers: 31471821 and 31570024; Natural Science Foundation of Anhui Province, Grant/Award Numbers: 1808085MC89 and KJ2015ZD21 National Natural Science Foundation of China, Grant/Award Numbers: 31471821 and 31570024; Natural Science Foundation of Anhui Province, Grant/Award Numbers: 1808085MC89 and KJ2015ZD21

In order to improve the measurement precision of the position tracking system when the test signal is weaker, put forward a kind of improved gain intelligent adjustment control algorithm(GIACA), learning the change rate of the signal strength automatically, forecasting the signals change value in the next time, adjusted the signal gain for the next signal sample according to this algorithm, to make the input signal to achieve maximum, so as to improve the resolution of the input test signal. and also when the input signal is powerful, the GIACA algorithm will make the gain smaller, so the input signal will be no more than the maximum input range. To achieve the quick tracking location to the goal, define a fast tracking location interval for the sensor, when signals change in this linear interval of the sensor, the relation between the moving target and the output signal of the sensor is linear, so the moving target can be located by one step. Experiments show that when the signal is weaker, this algorithm can make the control accuracy within 0.022mm.

A model for computing the albedos and BRDF (bidirectional reflectance distribution function) of inhomogeneous land surfaces consisting of two different components has been developed. An empirical equation, based on the model results, for calculating albedos of inhomogeneous land surfaces and avoiding errors caused by shadowing effect was set up.

The Pragmatic-context acts as an important role in pragmatic web oriented services discovery where the context is changing rapidly. This paper proposes a method for services discovery fitting to the dynamic environment called pragmatic-context. We figure out the ways include how to represent the context, how to determine it, and how to use it to influence the activation of user preferences to provide user with more tailored personalized services.

In order to improve independence and autonomy capability in Web services deployment and publishment, and enhance understanding or updating capability of service knowledge between service agents in service discovery and composition. Following a conjunctive study of agent and Semantics Web services technology, service knowledge model and extended service description layers are proposed to accommodate agent negotiation, and design methods for revising and updating service agent’s belief knowledge. It finally overcomes those defects that Semantics Web service can only comprise straightforward computational procedures with passive and predictable behaviors.

Pragmatics Web Service is a novel pattern for designing and deploying Web Services with the concept of pragmatics as its knowledge foundation. It primarily concerns preference, context, communication and negotiation of service participants, so that the real meaning for conveyed message can be apprehend by the service requester or provider. In this paper, we propose an agent negotiation framework towards Pragmatics Web Service. First, we abstract the rule and policy for access control to private information about context, preference towards the Pragmatics Web Service. Second, we have formalized the access control rules, context information and preference policy, and stored them in the service ontology base possessed by service agent. Finally, we implement the ContractNet protocol negotiation by a house-leasing case under control of the rules, and compare experimentally the utility value of various negotiation strategy between service requester and service provider.

In order to better make an agreement on both the discovery results of Semantic Web services and the intentions of the service requester, advance the accurate rate of service discovery, and improve the automation performance in service discovery and selection. We add the context knowledge of service provider and requester to service representation, and employ the planning method to achieve the understanding for the private ontology concepts between service participants. Experiments using the standard services test sets show that the performance of service discovery is improved significantly, though the time of discovery is delayed. Especially, when domain ontologies which are used to describe concerning services have many semantics difference, the result of discovering services is more precise. The innovations of this paper are to propose a semantics concept model for the Pragmatics Web service and a service discovery algorithm based concept planning understanding.

In order to improve the scalability, reliability and stability of the semantic Web service composition system, and to achieve ontology-based semantic Web services composition efficiently, this paper presents a P2P-based Semantic Web services (P2PSWS) composition system architecture. This architecture combines the advantages of centralized and decentralized structures. It distributes the functions of UDDI to the local Web nodes, and groups Web nodes and public Web nodes. This paper designs a localized mechanism of semantic Web services in CAN-based P2P networks to ensure that each service is registered in a specific node of the public Web. The registration services of public Web nodes are divided by the area and shared by all nodes. The running result of finished prototype system shows that the P2PSWS structure helps to overcome the problem "the failure of a single node" on the traditional structure of public Web services and expands the capacity of a P2P system, and that the P2PSWS structure achieves an efficient ontology-based semantic Web services composition.

The basic purpose of QoS management is to provide differentiated services and quality guarantee for users. Then how to evaluate the services provided by the system is very important. In the paper, a multi-level QoS management and evaluation architecture for network services is proposed, which supported adjustable selection and reconfiguration of QoS evaluation indexes. With the number of evaluation indexes increasing, eliminating the correlation between indexes is a key issue before QoS evaluation. Reference to Dijkstra shortest path algorithm, a dynamic index reduction algorithm is proposed. To eliminate the correlation of synthetic indexes is to get a set of indexes which the correlation degree is minimum. Examples show that the more indexes, the more efficient the dynamic algorithm can be.

Co-stimulations are very important in LAN AISs, but there are few automatic co-stimulation algorithms or approaches at present, and almost all of co-stimulations are implemented by network-administrators. We try to find an automatic co-stimulation algorithm to replace the administrators in LAN AISs. Detectors employed to detect abnormal packets are called NS-detectors. Detectors employed to detect normal packets are called PS-detectors. Each NS-detector can detect a different kind of potential abnormal packets. Each PS-detector can describe a different kind of normal network behaviors. The NS-detector generation algorithm and the PS-detector generation algorithm are presented first. Based on them, an automatic co-stimulation algorithm for LAN AISs is described in detail. Co-stimulations in LAN AISs can be implemented automatically with the algorithm. The administrators can still implement co-stimulations, but their co-stimulations are not important. The feasibility of the algorithm is illustrated with our experiments in laboratory. Our further work is to illustrate more the feasibility of the algorithm in the Internet environment.

Anomaly detection can detect unknown or new intrusions, and there are increasing interest in it. A normal network behavior model is necessary in any anomaly detection. Assuming that abnormal network behaviors are obviously different from normal ones, there should be some abnormal network packets that are obviously different from normal packets. Normal network packets are disassembled into binary strings whose lengths are l, and all the strings construct a set Unormal. The normal network behavior model is a set Umodel. The length of each element in Umodel is also l. Umodel is made up of those elements each of which matches at least one element in Unormal and doesn't match any other element in Umodel. Normal network behaviors hide in Umodel. The size of Umodel is discussed. Experimental results indicate that abnormal network behaviors can feasibly be detected with Umodel. Further work is to construct a more feasible Umodel to put into practice.

In this paper, we concentrate on the problem of routing and bandwidth assignment in GMPLS networks. We proposed a new restoration routing algorithm in GMPLS networks with optimized bandwidth. In this new algorithm, we consider multiple network optimizing objectives to setup a LSP with maximize profit and shortest path under the limited resources. By comparing and analyzing with the traditional algorithm, it is much better than the algorithm, which only considers one optimizing objective. In practice it is enough to find a solution, which does not use more bandwidth than the available technology allows.

A nonlinear dynamic model combined TCP and UDP under RED mechanism has been presented in this paper by modified a previously developed one. We linearized the model and added the feedback control mechanism that is introduced by RED, and then educed a proposition. Based on this proposition, we analyzed the impact of several parameters on the system stability, and we can present design guidelines for choosing network parameters that lead to stable operation of the linear feedback control system. We also performed simulations using NS2, and the results show that our analysis is suitable.

A fluid-based model combined TCP and UDP under RED mechanism has been presented in this paper based on a previously developed one. We linearized the model and added the feedback control mechanism that is introduced by RED, and then educed three propositions. Based on these propositions, we can present design guidelines for choosing network parameters that lead to stable operation of the linear feedback control system. We also performed simulations using NS2, and the results show that our analysis is suitable.

JASIAC (Java-based Active-network Secure Inter Active Application Communication) provides a mechanism to solve the security problem for active application communication for active networks. JASIAC can work against "un-authorization access" and "masquerading" quite well and work efficiently with "malicious access " and "direct DoS attack". It stores the variables and methods to be published in a public variable pool and public method pool respectively, so it makes the security manageable and efficient; it also provides multilevel security mechanisms such as timed variable, hiding inner name, parameter by value and read-only parameter to make the security reliable and flexible.

Modern requirement of dynamic Web Services rely increasingly on composing concurrent, distributed, mobile, re-configurable and heterogenous services, and substantial progress has already been made towards composed Web Services. In this paper, first, we proposed a life cycle of composed Web services, then designed a model named Service-Cloud model based on the process of forming clouds in nature. Finally, based on Service-Cloud model, we design and implement a prototype.

As a new programmable network architecture, the active network supports the development, verification and deployment of new network protocols and services. It is not used widely as we expected. The main reason is that its security has not been resolved. We introduce an active network security prototype designed by a pluggable module. It implements three aspects of security, including cryptography and digital signatures; authentication and authorization; revocation; etc. Especially, cryptography solves the integrity and confidentiality of active codes, and the decode mode implements cryptography's replacement and extensibility. Our system is dual nonrepudiation on both. Nonrepudiation on both is that the sender cannot deny that he sends the message; dual nonrepudiation means that nonrepudiation has been done in digital signature authentication and authorization authentication. The section of revocation designed according to the active network guarantees the validity of active code's execution. We measured latency and throughput of the experimental active network on two services: a prototype for active networks, a prototype of security for active networks. In fact, the security techniques applied in our system have little influence on the latency and throughput of active networks.

In this paper, we present a knowledge discovery system, Data Fusion Supported Frequent Episodes Discovery (DFSPED), for service-oriented proactive fault management in communication networks. The concept of network service topology is proposed first, and context-free grammars and network service dependence graph are used to model the service-oriented proactive fault management. Secondly, with the approaches of data fusion, two catalogues of important fault-pertinent data sources, i.e., service-oriented trouble-reporting data and real time alarm messages, are fused by temporal and spatial associations. KDD techniques are applied to perform incremental mining in the fused sequential events, finding frequent episodes among faults, alarms and service. Fast restoration of key service interruption, fault prediction and preventive maintenance benefit a lot from the discovered episodes.

The culture medium of Beauveria amorpha Hohn. exhibited strong radical scavenging properties. Activity-directed fractionation assisted by a radical scavenging assay on TLC afforded two active compounds which were identified as 6-methyl-2,4-dihydroxyphenyl 4-O-methyl-beta-D-glucopyranoside (1) and (-)-terredionol (2). Compound 1 displays radical scavenging and lipid peroxidation inhibitory activity comparable to those of TroloxC, ascorbic acid or quercetin.