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As for a pipe-line system subjected to complex operations, an approach is proposed to synthesize the controller via Petri nets (PNs) such that the plant is run as concurrently as possible and the loads of equipments are balanced. A P-timed and labeled PN is designed to model the whole process of a pipe-line system, where tasks, including transporting material from one tank to another and cleaning tank, are represented by operational places, and level sensors amounted in tanks are represented by labels assigned to transitions. Further, monitor places are designed to resolve the conflict relations among tasks due to the shared valves and pipes. An method is presented to translate an PN controller into a CIF3 (Compositional Interchange Format) model, which can be converted into a PLC program in the CIF3 tool. A beer filtration plant is taken as an example to illustrate the approach, and its simulation experiments are carried out to verify the theoretic results.

A formal approach is proposed for planning a team of mobile robots such that no collision occurs and tasks represented by a Boolean specification are satisfied. It should be specially noted that the order, by which the given tasks are executed, is taken into account by the specification. First, a team of mobile robots and their environment are modeled as a Petri net (PN). Second, a method is presented to design place nodes enforcing a given specification on the PN model. Consequently, the resultant PN can be used to model the robot team’s behaviors that satisfy the specification. Third, an optimal problem, minimizing the total traveling distance that the robots take to perform given tasks, is formulated as an integer linear programming (ILP) problem via the PN model. By solving the ILP problem, the optimal action sequence is obtained, which actually means an optimal strategy to schedule robots.

The routing of automated guided vehicles (AGVs) is playing an increasingly important role in modern logistics. AGVs routing problem is a complex combinatorial optimization problem. It fails to get the desired results of solving this problem using meta-heuristic algorithms due to its high real-time demand. Large AGVs systems in engineering are usually simplified by adding regulations, which may lead to getting only sub-optimal solutions. In this paper, we present a deep reinforcement learning algorithm to solve the AGVs routing problem. Firstly, the AGVs routing problem is modeled by a Markov decision process (MDP), enabling real-time routing. Secondly, according to the properties of the working scene of AGVs, asynchronous DQN (deep Q-network) is exploited to serve as the base framework of reinforcement learning. More importantly, the map of the working scene is discretized and represented using the embedding technique. Compared with one-hot mode, the input size of the embedding mode is much smaller, greatly improving the training speed. The extracted embeddings are built into conflict vectors, which are finally processed by LSTM (long short-term memory). Experiments show that the proposed algorithm has effectiveness both in real-time responding speed and getting high-quality solutions.

Siphon control has been utilized as a general methodology for systems of simple sequential process with resource (S3PR) deadlock systems. Although siphon control imposes additional control places on S3PR systems, it cannot guarantee that the maximum permissiveness is achieved. To solve the problem of deadlock prevention for S3PR, a new policy to design a deadlock-free supervisor with the maximally permissive system is proposed using additional transitions. Additionally, this approach can solve the problem of deadlock prevention for systems of sequential systems with shared resources (S4PR) system models.

Objective To develop and validate a radiomics prediction model for individualized prediction of perineural invasion (PNI) in colorectal cancer (CRC). Methods After computed tomography (CT) radiomics features extraction, a radiomics signature was constructed in derivation cohort (346 CRC patients). A prediction model was developed to integrate the radiomics signature and clinical candidate predictors [age, sex, tumor location, and carcinoembryonic antigen (CEA) level]. Apparent prediction performance was assessed. After internal validation, independent temporal validation (separate from the cohort used to build the model) was then conducted in 217 CRC patients. The final model was converted to an easy-to-use nomogram. Results The developed radiomics nomogram that integrated the radiomics signature and CEA level showed good calibration and discrimination performance [Harrell's concordance index (c-index): 0.817; 95% confidence interval (95% CI): 0.811-0.823]. Application of the nomogram in validation cohort gave a comparable calibration and discrimination (c-index: 0.803; 95% CI: 0.794-0.812). Conclusions Integrating the radiomics signature and CEA level into a radiomics prediction model enables easy and effective risk assessment of PNI in CRC. This stratification of patients according to their PNI status may provide a basis for individualized auxiliary treatment.

As for a class of automated guided vehicle systems (AGVS) that are partially controllable and with undeterministic behavior, a method is presented to design a maximally permissive controller that avoids any collision among vehicles via labeled Petri nets. It is not sure which area a vehicle enters after it leaves one because of insufficient sensors. Furthermore, a vehicle may uncontrollably enter some areas because of insufficient activators. By modeling the former case by multiple transitions labeled by a same symbol, and the latter case by an uncontrollable transition, an AGVS is represented by a labeled Petri net that is partially controllable. The whole net is partitioned into a set of dangerous regions that are controllable such that the uncontrollable issue is addressed. A method is proposed to compute the consistent marking set for a given observed sequence. By the resultant consistent marking set, the marking of each dangerous region is computed, and can be used to design a control action t o prevent each vehicle from entering each dangerous region where there is one AGV already. As a result, the maximally permissive controller is obtained.

Fixing the phases is one of the common methods to control an urban traffic network. Once a road is filled with a high traffic flow approaching its capacity, the conventional traffic light controller is not able to handle this traffic congestion phenomenon well. In this paper, we propose a novel regulatory traffic light control system to handle such traffic congestion by using synchronized timed Petri nets (STPNs). Three kinds of intersections in an urban traffic network are defined and employed to demonstrate our new regulatory traffic light control system models. Finally, the liveness and reversibility of the proposed STPN models are proven through the reachability graph analysis method. To our knowledge, this is the first work that solves a traffic congestion problem with a regulatory traffic light control technique that is effective in preventing vehicles from entering traffic congestion zones.

We prepared activated carbons (ACs) from coal samples ranking from lignite to anthracite. The pore structures and surface functional groups of the obtained ACs were examined by nitrogen adsorption isotherm, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, and Boehm’s titration method. Isothermal adsorption experiments using methylene blue (MB) solution were conducted to evaluate the adsorption capacities of the ACs. The obtained ACs had different sorption properties due to their differences in structural characteristics and surface chemical groups. The maximum adsorption was achieved using the ACs made from low-ranked lignite coals. The MB adsorption process could be described well by the intra-particle diffusion model with a wide range of effective diffusion coefficients. The results indicated that both the proportion of mesopores and the number of basic sites within the ACs mainly governed the MB adsorption capacities.

Considering the great potential of electric vehicles (EVs) in relieving energy and environmental crisis, this paper proposes an integrated motion and battery control method for the eco-driving of EVs. The goals are to satisfy the power demand of certain driving cycles with minimal energy consumption and to guarantee safe operations of the battery at the same time. Specifically, we consider both the vehicle level motion dynamics and the battery dynamics for an integrated EV eco-driving model. Model predictive control (MPC) is utilized to handle the multiple conflicting objectives and system constraints. To reduce the possible heavy computational burden of the online optimization problems, a successive linearization approach in the framework of MPC is applied to the prediction model to achieve a trade-off between control performance and computational complexity. Standard driving cycles are employed to test the effectiveness of the proposed algorithms. Simulation results show that the integrated motion and battery control can achieve the eco-driving goals in various test scenarios.

Purpose: Besides the smoking and occupational exposures, heritable factors have been proven to be a risk factor for lung cancer by several population-based studies, which would misestimate the risk of lung cancer. Patients and methods: To quantify the magnitude of the high risk of lung cancer with family history, we performed a case-based study with 1373 enrolled individuals, which may be more accurate than a population-based study. Results: Risk of lung cancer was higher in people with lung cancer family history than in the control group (OR 2.50, p

Once a road is with a high traffic density over its loading, the traffic management has to face the fact that how to alleviate the traffic congestion and how to prevent new traffic jams from being happening in the neighbourhood. This study presents a new control strategy for alleviating the traffic congestion. For this purpose, the authors employ VISSIM to simulate and analyse of an urban traffic congestion problem. In addition, two kinds of traffic light orders are involved. On the other hand, an urban traffic network with three kinds of intersection is used to evaluate their new congestion control policy. Finally, they also demonstrate three scenario cases low, middle, and heavy traffic flow works to compare with normal regular traffic light control rules, the multiline control strategies and their new control policy. Simulation results show that their new proposed traffic control policy is the best one among the others. It is worthy of note that their new proposed policy not only alleviates successfully the congestion problem but also prevents new traffic jams from being happening in the neighbourhood.

Advanced information and communication technologies can facilitate traffic incident management. If an incident is detected and blocks a road link, in order to reduce the incident-induced traffic congestion, the incident information should be announced to the travelers who drive to the blocked link. This work focuses on the design of an incident message dissemination strategy by selectively delivering incident information to those potentially affected drivers in a traffic network. Time-dependent shortest path algorithms are used to generate a subnetwork whose vehicles should receive such information. To evaluate the performance of the proposed strategy, a simulation approach based on a detailed cell transmission model is used. The results can be used in advanced traveler information systems to improve the state of the art in preventing urban road traffic congestion caused by incidents.

Timed Petri nets (TPNs) are useful for performance evaluation of discrete event systems due to their mathematical formalism. This paper focuses on their use to model the preemption of emergency vehicle systems. The advantage of the proposed approach is the clear presentation of traffic light behaviors in terms of conditions and events that cause the preemption of phases being changed. The resulting models allow one to identify and thus avoid urgent spectacles in such systems by conditions and events of the model that control the phase of traffic light alternations. Moreover, this work proposes a new emergency vehicle preemption policy to ensure that emergency vehicles can pass through intersections with no or less delay. The analysis is performed to demonstrate how the models enforce the phase of traffic transitions by a reachability graph with time information. The liveness and reversibility of the proposed model are verified. To our knowledge, this is the first work that employs TPNs to model an emergency vehicle preemption system and identify its urgent spectacles for the purpose of their complete avoidance. This helps advance the state-of-the-art in traffic safety related to the intersection of roadways.

Some population-based studies involving lung cancer patients have reported that inherited susceptibility is responsible for the familial aggregation observed in non-smoking lung cancer patients; however, it has been found that the false-negative rates in clinic-ascertained probands are significantly lower than population-ascertained probands. In this clinic-based study, we sought to determine the relationship between a family history of cancer and lung cancer risk in Chinese never-smokers.In this clinic-based case-control study, all 318 probands and 509 controls were Chinese. The data on demographic characteristics, age, gender, race, lung disease history, living environment, occupational exposure, and smoking history were collected from a structured questionnaire. Multiple conditional logistic regression was used to estimate adjusted odds ratios (aOR) and 95% CIs after adjusting for possible confounders.The risk of lung cancer was increased in individuals with a family history of lung (aOR, 3.21; p0.001) or any other cancer (aOR, 1.79; p0.001). Analyses were carried out using stratified relative gender; first-degree female relatives tended to have a higher risk than first-degree male relatives. Similarly, the aOR for a female developing a malignant tumor was two times greater than controls.Our analysis provides further evidence of the importance of genetic factors underlying lung cancer in patients who are never-smokers, especially in patients with a maternal history of cancer.

Mass amount of equipment and harsh operating condition in steel plants require comprehensive management system, along with lubrication techniques such as lubricating oil quality improvement, used oil monitoring, etc., to ensure proper tribological condition for all mechanical components. In that case, cost management is essential to evaluate the performance of tribology management. This paper is intended to discuss the system establishment, scope of work and actual applications of tribology management in China Steel.

Islanding detection is an essential protection requirement for distributed generators for personnel and equipment safety. This study presents a new active islanding detection method via current injection disturbance using intelligent tracking control of the active and reactive power commands. First, an active islanding detection method based on injecting a disturbance signal into the system through the d-axis current which leads to a frequency deviation at the terminal of the RLC load when the grid is disconnected is proposed. The feasibility of the proposed method is evaluated under the UL1741 anti-islanding test configuration. Then, to further improve the performance of the islanding detection method, an Elman neural network intelligent controller is adopted to replace the proportional-integral controller used in the traditional injection method for islanding detection. Moreover, the network structure and the online learning algorithm are described in detail. Finally, the feasibility and effectiveness o...

Cognitive radio (CR) is a promising method suitable for solving inefficiency spectrum policy by opportunistically identifying the vacant portions of the spectrum that are used by primary users (PUs). In cognitive radio ad hoc networks (CRAHNs), secondary users (SUs) can opportunistically utilize the spectrum that is available from PUs. In this paper, we propose a neighbor-aware distance estimated medium access control (NMAC) protocol for CRAHNs to mitigate the hidden and exposed terminal problems of multichannel CRAHNs. In this study, transmitter power control is based on the neighbor-aware estimated distance between SU communication pairs; this increases throughput, and reduces PU outage probability. We also compare our proposed scheme with existing MAC protocols for CRAHNs. We show that the NMAC will improve the channel spatial reuse, the normalized throughput, and reduce PU outage probability.

Wafer fabrication tends to small batch, and single wafer processing is effective in cluster tools. With the decrease of processes, redundant processing modules are adopted to improve the utilization of cluster tools. The scheduling of mixed-processing of multi-variety wafers should be developed for dual-armed cluster tools. Based on resource oriented Petri net model, we analyze the process by the traditional swap strategy, then wafer processing cycle time and robot cycle time are obtained. A theorem of the schedulability is achieved by analyzing the processing parameters of multi-variety wafers. The schedule is obtained by a scheduling determining programming. Finally, illustrative examples are presented to show the usage of the programming.

In the paper, the loading test of jointed rock mass is simulated by the finite element software. The numerical simulation experiment was completed on the intact rock mass, and results are compared with the laboratory test. Results show that numerical simulation method to study mechanical characteristics of jointed rock mass is feasible. Based on numerical simulation results on jointed rock mass, four types of failure of jointed rock mass are put forward, which are rock mass loading failure, joint loading failure, shear failure and approximate shear failure. Relative the joint thickness, the joint angle has more influence for shear strength properties of jointed rock mass. The elastic modulus of jointed rock mass is greatly influenced by the joint thickness and joint angle. With the different joint thickness, the elastic modulus of jointed rock mass is basically reached the minimum value when the joint angle is 10°~25°.

Timed Petri nets (TPNs) are useful for performance evaluation of discrete event systems due to their mathematical formalism. This paper proposes the use of TPNs to model parallel railroad level crossing traffic safety control systems. Double-track railroad lines using TPNs are illustrated. The resulting models allow us to identify and thus avoid critical scenarios in such systems by using conditions and events of the model that control the phase of traffic light alternations. Their analysis is performed to demonstrate how the models enforce the phase of traffic transitions using the method of a reachability graph with timed information. The liveness and reversibility of the proposed model are verified. This helps advance the state-of-the-art in traffic safety related to the intersection of railroads and roadways.

Timed Petri nets (TPNs) have been utilized as visual formalism for the modeling of complex discrete-event dynamic systems. They illuminate the features in describing the properties of causality and concurrency. Moreover, it is well known that a synchronized TPN (STPN) allows us to present all of the concurrent states in a complex TPN. In this paper, we propose a new methodology to design and analyze an urban traffic network control system by using the STPN. In addition, the applications of the STPN to eight-phase, six-phase, and two-phase traffic-light control systems are modularized. The advantage of the proposed approach is the clear presentation of the behaviors of traffic lights in terms of the conditions and events that cause phase alternations. Moreover, the size of the urban traffic network control system can be easily extended with our proposed modular technique. An analysis of the control models is performed via a reachability graph method to demonstrate how the models enforce the transitions of the traffic lights.

The objective of this study was to analyze the predictive roles of VEGF/KDR/Ras/MAPK gene expression in patients with advanced non-small-cell lung cancer (NSCLC) treated with bevacizumab plus chemotherapy. Twenty-five patients participating in an open-label phase IV trial (SAiL, MO19390) with available tumor tissues were analyzed. The mRNA expression levels of VEGF, kinase insert domain receptor (KDR), Ras, and mitogen-activated protein kinase (MAPK) in tumor tissues were detected using real-time quantitative PCR methods. The relationships between gene expression and disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were assessed. Patients with lower Ras expression had a longer PFS and OS than patients with higher expression (median PFS, 9.9 vs 5.5 months, χ(2)=3.944, P=0.047; OS, 19.3 vs 7.1 months, χ(2)=9.384, P=0.002). The PFS and OS of patients with lower and higher MAPK expression exhibited a marginal and significant difference (median PFS, 9.9 vs 5.5 months, χ(2)=3.464, P=0.063; OS, 19.3 vs 9.7 months, χ(2)=5.298, P=0.021), respectively. Multivariate analyses using Cox's proportional hazards model showed that Ras is an independent predictor of OS (χ(2)=9.384, P=0.002). No differences in DCR were found according to Ras expression level. The results indicate that Ras is an independent predictor of OS. Thus, patients with lower Ras expression are most likely to benefit from bevacizumab plus chemotherapy treatment regimen. Patients with higher levels of Ras should receive other inhibitors that target Ras. The results also suggest that gene therapies that decrease RAS expression combined with bevacizumab may improve lung cancer treatment. Although there is a very important implication to patient selection in the target therapy, the data in this study are very preliminary owing to the too small sample size. Therefore, further research involving large numbers of patients and a prospective assessment of low and high RAS mRNA expressions getting the same treatments need to be done before conclusions can be made.

An active islanding detection method using d -axis disturbance signal injection with intelligent control is proposed in this study. The proposed active islanding detection method is based on injecting a new disturbance signal into the system through the d -axis current that leads to a frequency deviation at the terminal of the resistance inductance and capacitance (RLC) load when the grid is disconnected. The feasibility of the proposed method is evaluated under the UL1741 anti-islanding test configuration. The proposed d -axis disturbance signal-injection method is intended to achieve a reliable detection with quasi-zero non-detection zone, minimum effects on power quality and easy implementation without additional sensing devices or equipments. Moreover, in order to achieve accurate tracking control of active and reactive power and rapid response of the islanding detection of the distributed generator (DG) system, a wavelet fuzzy neural network (WFNN) intelligent controller is proposed to replace the conventional proportional-integral controller for the control of the DG system. Furthermore, the network structure and the online learning algorithm of the WFNN are introduced in detail. Finally, the feasibility and effectiveness of the proposed d -axis disturbance signal-injection method are verified with experimental results.

A transition-controlled deadlock detection and recovery prevention policy is presented for a subclass of Petri nets used to model flexible manufacturing systems. The subclass is called systems of simple sequential processes with resources (S 3 PR). The proposed policy is different from the standard deadlock prevention policies. Instead of adding control places, this policy adds a controlled transition to solve a group of deadlocked markings that have the same graph-based property. Finally, the results of our study indicate that the proposed policy appears to be more permissive than those existing ones that add control places.

There is no published overview of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) failure modes in advanced non-small-cell lung cancer (NSCLC). This study aimed to classify the diversity of EGFR-TKI failure, and to investigate the usefulness of clinical modes in subsequent management and prognosis.One-hundred and twenty consecutive clinical trial patients with EGFR-TKI failure were enrolled as the training set to establish a clinical model based on clinical factors. Another 107 routine patients were enrolled as the validating set according to a Bayes discriminant analysis. EGFR mutations and c-MET amplification were analyzed. Kaplan-Meier survival analysis was used to test the differences among three clinical modes and subsequent management.The duration of disease control, evolution of tumor burden, and clinical symptom were verified as feasible grouping variables. A correct grouping rate achieved 87.9%. The cohort was classified into three groups, as follows: 130 patients with dramatic progression, 42 with gradual progression, and 55 with local progression. Progression-free survivals (PFSs) for the dramatic progression, gradual progression, and local progression groups were 9.3, 12.9, and 9.2 months, respectively (P = 0.007). Overall survivals for the groups (OSs) were 17.1, 39.4, and 23.1 months, respectively (P0.001). TKI continuation was superior to switching chemotherapy in a subsequent setting for gradual progression (39.4 months vs. 17.8 months; P = 0.02). The difference of EGFR or c-MET among the three groups was not significant.Clinical modes of EGFR-TKI failure could favor strategies for subsequent treatment and predicting a survival benefit in advanced NSCLC.

Firstly analyzed the stability of blocks with block theory and secondly evaluated the stability of blocks with three-dimensional limit equilibrium method and finally evaluated the whole stability of slopes. Stability analysis for the slope of Maerdang hydropower station shows that natural slopes which belong to the upstream of Hadehei ditch on the right bank will not occur wedge slide, tailrace slopes of hydropower station have not sliding slopes searched which are in potential slide, if taking some measures to reinforce the stability of man-made slopes on the face rock-fill hub, which may meet the demand of the specification.

Amending the normal stress over the slip surface based on the stress field by numerical analysis, applying the three-dimensional global limit equilibrium method to the stability analysis of tension-slackened rock mass in the right bank of Yagen hydropower station. Stability analysis shows that if do not take any measures, the loose rock mass stability can cater to the Specification demand, but some small sliders is in the limit state under the water and earthquake condition, if use the cutting slope and unloading scheme, the whole loose rock mass and the all small sliders can meet the Specification standard stability requirements.

The theory of regions is an important method to derive an optimal and liveness-enforcing supervisor for a flexible manufacturing systems based on Petri nets. It first partitions the reachability graph into a live zone (LZ) and a deadlock zone (DZ). Then, activity places are used to construct place invariants (PIs) to prevent the system from entering DZ and permit all markings in LZ. This work studies the reduction of the number of places to be considered in the optimal PI designs. First, the concepts of critical transitions and critical activity places are defined, and an algorithm is provided to compute the sets of critical and uncritical activity places. Then, the proof of that only critical activity places need to be considered in such optimal PI designs is established.

A formal approach is proposed for optimal scheduling and control problems in a batch chemical system. First, a method is presented to model it as a P-timed Petri net (PN), which can graphically describe how it may operate according to recipes, and which valve and pipeline are required by each operation. Second, this P-timed PN model is simplified according to the conflicts caused by the shared valves, and, in turn, it is utilized to define a linear programming where the optimal objective is the minimal processing time. Further, the A* algorithm is used to solve this programing to obtain an optimal strategy. Finally, via the P-timed PN model, a method is obtained to compute a control matrix for valves that can guarantee the optimal strategy. A typical batch system is used to illustrate the theoretic results.

Based on the wedge stability analysis method specified in Design Specification for Concrete Dams (DL5108-1999, in Chinese), the limit state equation applied to deep-seated sliding stability under the earthquake has been deduced, and the safety factor of limit state to quantitatively assess the deep slide of gravity dams has been established. The computation for the project shows that the limit state equation is accurate and applicable.

Deadlocks are an important problem in resource allocation systems such as flexible manufacturing systems. The theory of regions and the siphon-based method are usually used in the most deadlock prevention policies. The theory of regions that can obtain a maximally permissive controller is usually considered to be a natural solution with seasonable computational cost for flexible manufacturing systems. The selective siphon method allows one to use fewer control places than the conventional one. This paper employs both methods above. The former can identify the set of curial marking/transition–separation instance; the latter can reduce the computational cost. We can infer that the novel policy is the most efficient policy than the traditional methods, and also, the maximal permissive behavior of Petri net models can still be obtained.

An intelligent-controlled doubly fed induction generator (DFIG) system using probabilistic fuzzy neural network (PFNN) is proposed in this study. This system can be applied as a stand-alone power supply system or as the emergency power system when the electricity grid fails for all sub-synchronous, synchronous, and super-synchronous conditions. The rotor side converter is controlled using the field-oriented control to produce three-phase stator voltages with constant magnitude and frequency at different rotor speeds. Moreover, the grid side converter, which is also controlled using field-oriented control, is primarily implemented to maintain the magnitude of the DC-link voltage. Furthermore, an intelligent PFNN controller is proposed for both the rotor and grid side converters to improve the transient and steady-state responses of the DFIG system at different operating conditions. The network structure, online learning algorithm, and convergence analyses of the PFNN are introduced in detail. Finally, the feasibility of the proposed control scheme is verified using some experimental results.

To evaluate the efficacy and safety of nedaplatin/gemcitabine (NG) and carboplatin/gemcitabine (CG) in the management of untreated advanced non-small cell lung cancer (NSCLC).Sixty-two patients with previously untreated advanced NSCLC were recruited between June 2006 and November 2007. Subjects were randomly assigned to the NG arm (n=30) and the CG arm (n=32). Only patients (24 and 25 in the NG and CG arms, respectively) who completed ≥2 chemotherapy cycles were included in the data analysis. The primary outcome measure was the objective response rate (ORR). The secondary outcome measures included progression-free survival (PFS), overall survival (OS) and adverse events.There were no statistically significant differences in the efficacy measures (ORR, P=0.305; median PFS, P=0.198; median OS, P=0.961) or in the major adverse events (grade 3/4 neutropenia, P=0.666; grade 3/4 anemia, P=0.263; grade 3/4 thrombocytopenia, P=0.212) between the two treatment arms. However, there was a trend towards higher ORR (37.5% vs. 24.0%), longer PFS (6.0 vs. 5.0 months), and less adverse events in the NG arm.NG regimen seems to be superior over CG regimen for advance NSCLS, but further investigation is needed to validate this superiority.

The theory of regions has been recognized as the powerful method of deadlock prevention policy for obtaining maximally permissive controllers. All legal and live maximal behavior of Petri net models can be preserved by using marking/transition-separation instances or event-state-separation-problem methods. However, they encountered great difficulties in solving all sets of inequalities that is an extremely time consuming problem. Additionally, the number of linear programming problems of legal markings is also exponential with net size when a plant net grows exponentially. This work proposes a novel methodology to reduce the above contributions. In this paper, the reachability condition equations in the theory of region can be reduced under the reduction approach. The problem of the issue can then be reduced. Moreover, a crucial marking/transition-separation instances is developed in our deadlock prevention policy that allows designers to employ few marking/transition-separation instances to deal with deadlocks. The advantage of the proposed policy is that a maximally permissive controller can be obtained with drastically reduced computation.

Deterministic and stochastic Petri nets (DSPNs) are well utilized as a visual and mathematical formalism to model discrete event systems. This paper proposes to use them to model parallel railroad level crossing control systems. Their applications to both single and double-track railroad lines are illustrated. The resulting models allow one to identify and thus avoid critical scenarios in such systems by conditions and events of the model that control the phase of traffic light alternations. Their analysis is performed to demonstrate how the models enforce the phase of traffic transitions by a reachability graph method. Their important properties are verified. In this paper, we employ DSPNs to model a parallel railroad level crossing system and identify its critical scenarios for the purpose of their complete avoidance. This helps advance the state-of-the-art in traffic safety related to the intersection of railroads and roadways.

Based on hyperbolic nonlinear elastic constitutive model of unloading rock mass, the anchoring rock mass of excavation spillway of a hydropower station has been taken for the study. And considering the impact of excavation unloading process, three reinforcement programs are compared and analyzed. Overall, the constraint by system anchors on deformation of the spillway slope is limited. If the limit on the slope deformation is higher, pre-stressed cables are necessary.

Deadlock prevention problem is an important issue in essence for flexible manufacturing systems (FMS). Many works make efforts in the issue. Theory of regions is recognized as one of the powerful deadlock prevention method for obtaining maximally permissive controllers. All legal and live maximal behavior of Petri net models can be preserved by using marking/transition-separation instance (MTSI) or event-state-separation-problem (ESSP) methods. However, solving all sets of inequalities are an extremely time consuming problem since all MTSIs and ESSPs need to be considered in the reachability graph of a deadlock FMS. In our previous work, we propose crucial MTSI (CMTSI) method to improve computational difficulty successfully. In this work, we further enhance the computational efficiency of CMTSI by combining critical markings and CMTSI methods. Experimental results reveal that this approach is more practical than the conventional methods.

Petri nets are employed to model flexible manufacturing systems (FMSs). However, the system deadlocked are possible happened. The conventional deadlock prevention policies are always to forbid the system entering the deadlock by using the control places. To obtain a live system, some dead markings must be sacrificed in the traditional policies. Therefore, the original reachability states of the original model can not be conserved. However, this paper is able to maintain all the reachability states of the original net and guaranty the control system live. Under our control policy, all number of reachability states of the original net will be preserved. Finally, two examples are performed that can reach the maximal permissiveness for FMSs using Petri net models (PNMs).

Statechart has been utilized as a visual formalism for the modeling of complex systems. It illuminates the features on describing properties of causality, concurrency and synchronization. The reachability structure is used to represented dynamic model by a Boolean function. In this paper, we try to describe State invariant method and equation function for hierarchical tree diagram. Finally, we used them to analyze the urban traffic control systems which are modeled by using Statecharts. Their formalism provides a concept of propositional logic for presenting control strategy.

A novel approach for probabilistic timed structure that is based on combining the formalisms of timed automata and probabilistic automata representation of the system is proposed. Due to their real-valued clocks can measure the passage of time and transitions can be probabilistic such that it can be expressed as a discrete probability distribution on the set of target states. The usage of clock variables and the specification of state space are illustrated with real value time applications. The transitions between states are probabilistic by events which describe either the occurrence of faults or normal working conditions. Additionally, the passage of discrete time and transitions can be probabilistic by mean of the theory of expectation sets to obtain a unified measure reasoning strategy.

Deadlock prevention, deadlock detection and deadlock avoidance strategies are used to solve the deadlock problems of flexible manufacturing systems (FMSs). The conventional prevention policies were always attempt to prevent the system entering the deadlocked situation by using a few control places. On can know that one prohibits the deadlocked markings, some dead markings will be sacrificed. Therefore, the reachability states will become less than the initial net. However, our goal is to preserve all the reachability states of the initial net. Under our control policy, the deadlocks or deadlock zone will be channelized to live markings such that all the dead markings in reachability states will be conserved. Finally, an example is performed and can obtain the maximal permissiveness of a Petri net model. The other examples are all getting the same result. To our knowledge, this is the first work that employs the channelized method to prevent the deadlock problem for FMSs.

Timed Petri net (TPN) has been utilized as a visual formalism for the modeling of complex discrete event dynamic systems. It illuminates the features on describing properties of causality and concurrency. Moreover, it is well-known that synchronized timed Petri net (STPN) allows us to present all of the concurrent states in complex TPN. In this paper, we propose a new methodology to design, analyze and implement an urban emergency vehicle preemption control system by using STPN. The applications of STPN to two-phase traffic lights and emergency vehicle preemption are illustrated. The advantage of the proposed approach is the clear presentation of traffic lights’ behaviors in terms of conditions and events that cause the preemption phases alternations. Finally, a two-phase traffic lights control system with emergency vehicle preemption will be realized by using STPN. To our knowledge, this is the first work that employs STPN to model a two-phase traffic lights control system with emergency vehicle preemption system.

Statechart has been utilized as a visual formalism for the modeling of complex systems. It illuminates the features on describing properties of causality, concurrency and synchronization. In this paper, we try to describe a behavioral logical operations language by using Statecharts. The logical operation is a data structure that is used to represent by a Boolean function. This paper used them to analyze the models which are modeled by using Statecharts. Their formalism provides a concept of propositional logic for presenting control strategy. Finally, an example of level crossing traffic control systems is examined successfully.

We sought to find blood-based biomarkers that can be used to predict efficacy in advanced non-small cell lung cancer patients treated with bevacizumab plus chemotherapy. Blood was collected before treatment and after 6 weeks of therapy from patients who were participating in a phase 4 trial. Plasma vascular endothelial growth factor (VEGF) levels were evaluated by ELISA. A total of eight single nucleotide polymorphisms in four candidate genes were analyzed by PCR and sequencing. A total of 45 patients enrolled in a clinical trial at Guangdong General Hospital between August 2007 and March 2008 were used as subjects. The median survival times of OS was 25.6 and 13.4 months in the low and high groups, respectively, when the median posttreatment plasma VEGF level (46.63 pg/ml) was used as the cut-off point (P = 0.0284). Patients carrying the AA genotype at the −6C > A polymorphism in laminin 5 (LN5) were more likely to exhibit reduced hemoglobin compared with patients carrying the CA/CC genotype (OR = 8.364, χ2 = 5.34, P = 0.021). Similar associations were found at the −89A > G and −260C > A polymorphisms in LN5. Patients with the CC genotype at the −6C > A polymorphism in LN5 had an increased risk of neutropenia than those with the CA/AA genotype (OR = 4.444, χ2 = 5.116, P = 0.030). Our results show improved survival in patients with lower posttreatment plasma VEGF levels treated with bevacizumab plus chemotherapy; thus, the posttreatment plasma VEGF level may be a promising biomarker to predict clinical benefit early in the course of therapy. Polymorphisms in LN5 were associated with a reduced level of hemoglobin and neutropenia.

Statechart has been utilized as a visual formalism for the modeling of complex systems. It illuminates the features on describing properties of causality, concurrency and synchronization. In this paper, we try to describe the behavioral of the traffic lights by using Statecharts. We use Boolean function to make the traffic light controller behavior in a certain way. This paper used Boolean function to analyze the models which are modeled by using Statecharts. Their formalism provides a clear means for presenting control logic. Finally, an example of traffic light controller system is examined successfully.