Towards a Categorical Framework for Verifying Design and Implementation of Concurrent Systems

Process-oriented design and implementation of concurrent systems has important benefits. However, the inherent complexity of concurrent processes’ communication imposes challenges such as verifying consistency between the process-oriented design and implementation of a concurrent system. To deal with such a challenge, we use Galois connections, Failures and Category Theory to construct a formal framework for designing, implementing, analyzing and verifying consistency of concurrent systems. For the purpose of illustrating the framework, a running concurrent system is designed by Communicating Sequential Processes, implemented by a process-oriented programming language Erasmus.

Stage IV malignant transformation of mature cystic teratoma palliatively treated with concurrent chemoradiotherapy:A case report

BACKGROUND Malignant transformation(MT)of mature cystic teratoma(MCT)has a poor prognosis,especially in advanced cases.Concurrent chemoradiotherapy(CCRT)has an inhibitory effect on MT.CASE SUMMARY Herein,we present a case in which CCRT had a reduction effect preoperatively.A 73-year-old woman with pyelonephritis was referred to our hospital.Computed tomography revealed right hydronephrosis and a 6-cm pelvic mass.Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB)revealed squamous cell carci-noma.The patient was diagnosed with MT of MCT.Due to her poor general con-dition and renal malfunction,we selected CCRT,expecting fewer adverse effects.After CCRT,her performance status improved,and the tumor size was reduced;surgery was performed.Five months postoperatively,the patient developed dis-semination and lymph node metastases.Palliative chemotherapy was ineffective.She died 18 months after treatment initiation.CONCLUSION EUS-FNB was useful in the diagnosis of MT of MCT;CCRT suppressed the disea-se and improved quality of life.

MODELING METHOD FOR CROSSCUTTING CONCERNS IN CONCURRENT SOFTWARE SYSTEM

A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statechart diagrams, the primary system functions and corresponding traversal features are enveloped into various orthogonal regions of a composite state. The mutual relationships between orthogonal regions are implied by the orders of broadcast events. Using a modular transition system as a basic computational model, the formalization description of A-O statechart models is proposed. The precise semantics of model elements and modeling procedures is given. The example study indicates that the separation strategy of crosscutting concerns is implemented in the design phase of the concurrent software system with this method. Meanwhile, the software modeling method has advantages of loose coupling, adaptability and traceability.

Automatic and Hierarchical Verification for Concurrent Systems

Proving correctness of concurrent systems is quite difficult because of the high level of nondeterminism,especially in large and complex ones.AMC is a model checking system for verifying asynchronous concurrent systems by using branching time temporal logic.This paper introduces the tech- niques of the modelling approach,especially how to construct models for large concurrent systems with the concept of hierarchy,which has been proved to be effective and practical in verifying large systems without a large growth of cost.

Anthropogenic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(April–September) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the present day(PD,1994–2011) is double that in the early period(EP, 1964–81);the duration of HDEs increases by 60%. Climate experiments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthropogenic forcing to HDE decadal changes over China. Anthropogenic forcing changes can explain 60%–70% of the observed decadal changes,suggesting an important anthropogenic influence on HDE changes over China across the mid-1990s. Single-forcing experiments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthropogenic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in response to anthropogenic forcing are mainly due to the response of climatological mean surface air temperatures. The contributions from changes in variability and changes in climatological mean soil moisture and evapotranspiration are relatively small. The physical processes associated with the response of HDEs to GHG and AA changes are also revealed.

CCOC：An Optimizing Compiling System for Concurrent C Supporting Inter－process Code Analysis and Optimization

At present, there are some static code analyses and optimizations that can be applied to Concurrent C programs to improve their performance or verify their logical correctness. These analyses and optimizations are inter-process. In order to make their implementation easy, we propose a new method to construct an optimizing compiling system CCOC for Concurrent C. CCOC supports inter-process code analysis and optimization to Concurrent C programs and does not affect the system's portability and separate compilation of source programs. We also discuss some implementation details of CCOC briefly.

A Real-time Concurrent Product and Process Design System for Mechanical Parts

A real time concurrent product and process design system for mechanical parts is described in this paper. It consists of integrated product model, the expert system of product manufacturability evaluation and the controller of concurrent design. With the help of the controller of concurrent design, each feature of a part can be designed and evaluated based on manufacturing knowledge and resources, and can be modified according to the results of evaluation. The machining method of design feature can be selected based on manufacturing knowledge. So real time concurrent product and process design can be implemented based on integrated product model that is established based on generalized feature. Products and its design process can be optimized with the help of this system. The information and function integration of product design process can be realized. The time to market and the cost of products can be reduced.

Concurrent Design Study of the Petroleum Equipment CAD System

Military petroleum equipment, as the special device a nd tool for petroleum storage, transportation, filling, chemical analysis, detec tion and maintenance for the army, is an important means and basis of petroleum indemnificatory. To adapt to modern war in high-tech conditions, the petroleum equipment have to develop towards higher reliability, adaptability, maneuverabil ity, standardization, container and cell type with versatile multi-functions. As a new design theory and design process, concurrent engineering may prod uce remarkable benefit when applying to product development. With the aid of the state-of-the-art modeling and simulation technology, it foresees the future or even the whole life cycle of the products designed. Based on wide statistics and survey, the product design period is reduced by 1/2～1/3 with concurrent des i gn process. The application of concurrent design process in new petroleum equi pment development shall greatly accelerate the petroleum equipment updating an d promote their indemnificatory.

Application of Management Information System Planning in Concurrent Engineering for Wooden Furniture Industry

This research is a development in management information system （MIS） planning based on operation analysis and development according to concurrent engineering approach and reestablishment of database management. According to our case study industry, such industry currently used traditional network systems such as LAN, and ＂Bus Network＂ Network Topology. Client/Server distributed computing has a problem with database management in data redundancy, data inconsistency, and data independency. For Network Topology, Bus Network has problem with multitasking since the network are able to handle only a set of data at a time so the traffic problem will occur when multiple users request for the service. Thus, such condition is inconsistent with concurrent engineering which must be able to access the data simultaneously. As a consequence, this study develops a network system, network system of working system, using LAN and ＂Star Network＂ network topology. The file server processing distributed is an application while database is stored in host computer or file server but the data will be processed in users＇ computer. When the user needs to access the data, file server will send it to the user and the user can further analysis or manage such data in the user computer, so called ＂Hierarchical Database Model＂. Hierarchical database structure is easily developed like general organization command structure with different level of responsibility. In details, the data level in the database is divided into three levels including DBI, DB2, and DB3, so development of simultaneously systemic flow and access of various critical data is performed in parallel. Furthermore, this is consistent with access of all three data levels including： Level 1 is overall dataflow of both inside and outside the organization; Level 2 is dataflow of each division in the organization; and Level 3 is dataflow of subunit in each division in the organization. After systemize flow and access of data with concurrent engineering as mentioned, it provided optimal efficiency in the whole production system management reducing loss in the whole system of the organization

Discrete Event Net Based Modeling and Control System Design for Real-Time Concurrent Control of Multiple Robot Systems

This paper deals with control system design and implementation problems encountered in multiple robot systems. The methodology developed is depicted by a set of coordination mechanisms using hierarchical net structures and their accompanying rules. With the net models, the hierarchical and distributed control system is designed for an assembly task. Synchronization commands allow coordination of the movements of the robots. The net models make concurrency of the movements of the robots transparent to users. The net based machine controller executes robot motion control through the communication with the external robot controller using the command/response concept. Sensory signals indicating the change of state of robots are used to trigger or initiate tasks. Simultaneous movement of the robots is obtained by creating different background threads running in parallel under Windows OS. The multilevel hierarchical control system can be consistently constructed using net models.

Survival benefit of concurrent chemoradiotherapy for advanced ampulla of Vater cancer

BACKGROUND Currently,there is no standard adjuvant therapy for patients with resected ampulla of Vater(AoV)cancer.AIM To evaluate the effectiveness of adjuvant concurrent chemoradiotherapy(CCRT)in patients with advanced AoV cancer who underwent curative resection.METHODS This single-centered,retrospective study included 29 patients with advanced AoV cancer who underwent pancreaticoduodenectomy between 2006 and 2018.The impact of CCRT on advanced AoV cancer was analyzed.RESULTS The 1-,3-,and 5-yr recurrence-free survival(RFS)rates for patients with advanced AoV cancer were 82.8%,48.3%,and 40.8%,respectively,and the overall survival(OS)rates were 89.7%,62.1%,and 51.7%,respectively.Lymphovas-cular invasion was found to be a significant risk factor for RFS and OS in patients with advanced AoV cancer in the univariate analysis,whereas T stage and lymph node metastasis were significantly associated with OS in the multivariate analysis.Compared to the patients who did not receive adjuvant CCRT,those who received adjuvant CCRT did not show statistically significant improvements in the RFS and OS,although they had a significantly lower average age and significantly higher platelet-to-lymphocyte ratio.CONCLUSION Adjuvant CCRT did not improve survival outcomes in patients with advanced AoV cancer.These findings contribute to existing knowledge on the effectiveness of CCRT in this patient population and provide important insights for clinical decision-making.

On Distributed Concurrent Multi-Port Router Test System

This paper presents a framework of the distributed concurrent multi-port-testing test system (CMPT-TS) for IP routers under development at Sichuan Network Communication Key Laboratory. Having analyzed the actuality of concurrent testing for routers, this paper develops a distributed architecture of CMPT-TS and discusses its functional components in detail. Moreover, a new test definition language, CMPT definition language, is also introduced simply.

Programmed cell death 1 inhibitor sintilimab plus concurrent chemoradiotherapy for locally advanced pancreatic adenocarcinoma

BACKGROUND Pancreatic adenocarcinoma,a malignancy that arises in the cells of the pancreas,is a devastating disease with unclear etiology and often poor prognosis.Locally advanced pancreatic cancer,a stage where the tumor has grown significantly but has not yet spread to distant organs,presents unique challenges in treatment.This article aims to discuss the current strategies,challenges,and future directions in the management of locally advanced pancreatic adenocarcinoma(LAPC).AIM To investigate the feasibility and efficacy of programmed cell death 1(PD-1)inhibitor sintilimab plus concurrent chemoradiotherapy for LAPC.METHODS Eligible patients had LAPC,an Eastern cooperative oncology group performance status of 0 or 1,adequate organ and marrow functions,and no prior anticancer therapy.In the observation group,participants received intravenous sintilimab 200 mg once every 3 wk,and received concurrent chemoradiotherapy(concurrent conventional fractionated radiotherapy with doses planning target volume 50.4 Gy and gross tumor volume 60 Gy in 28 fractions and oral S-140 mg/m2 twice daily on days 1-14 of a 21-d cycle and intravenous gemcitabine 1000 mg/m2 on days 1 and 8 of a 21-d cycle for eight cycles until disease progression,death,or unacceptable toxicity).In the control group,participants only received concurrent chemoradiotherapy.From April 2020 to November 2021,64 participants were finally enrolled with 34 in the observation group and 30 in the control group.RESULTS Thirty-four patients completed the scheduled course of chemoradiotherapy,while 32(94.1%)received sintilimab plus concurrent chemoradiotherapy with 2 patients discontinuing sintilimab in the observation group.Thirty patients completed the scheduled course of chemoradiotherapy in the control group.Based on the Response Evaluation Criteria in Solid Tumors guidelines,the analysis of the observation group revealed that a partial response was observed in 11 patients(32.4%),stable disease was evident in 19 patients(55.9%),and 4 patients(11.8%)experienced progressive disease;a partial response was observed in 6(20.0%)patients,stable disease in 18(60%),and progressive disease in 6(20%)in the control group.The major toxic effects were leukopenia and nausea.The incidence of severe adverse events(AEs)(grade 3 or 4)was 26.5%(9/34)in the observation group and 23.3%(7/30)in the control group.There were no treatment-related deaths.The observation group demonstrated a significantly longer median overall survival(22.1 mo compared to 15.8 mo)(P<0.05)and progression-free survival(12.2 mo vs 10.1 mo)(P<0.05)in comparison to the control group.The occurrence of severe AEs did not exhibit a statistically significant difference between the observation group and the control group(P>0.05).CONCLUSION Sintilimab plus concurrent chemoradiotherapy was effective and safe for LAPC patients,and warrants further investigation.

一种基于Concurrent Apla语言的共享内存并发分布式算法2层验证方法

形式化验证共享内存并发分布式算法已成为当前极具挑战性的问题之一,尤其是在云计算、多核、无线传感器网络、分布式数据库、区块链环境下.该文基于研究团队在形式化规约语言和方法、算法形式推导和验证方面的已有工作,以自定义泛型抽象顺序设计语言Apla为基础,进一步研究并提出简明、高抽象用于并发分布式计算的Concurrent Apla语言,使其既支持顺序算法的验证又能有效地验证并发分布式算法.在依赖-卫式推理的基础上,提出一种新颖的2层并发分布式算法形式化验证方法,其中系统层用于处理并发级验证,而组件层用于处理顺序级验证.最后,通过2个实例验证了该方法的有效性和可行性.

COOPERATIVE DESIGN UNDER CONCURRENT ENGINEERING ENVIRONMENT

This paper outlines a concurrent engineering environment that supports interaction between members of a geographically dispersed multidisciplinary team who is engaged in engineering design activities. Some ideas of engineering design, especially conceptual design are reviewed. A deeper scientific analysis of intelligent design is discussed. A new problem solving strategy and methodologies to implement cooperative design are proposed. Finally, a conceptual model of a blackboard system for accomplishing conceptual design automation is presented. Its fundamental principles, system organization and key implementation techniques are investigated in detail.

An Algorithm to Construct Concurrent Reachability Graph of Petri Nets

Reachability graph is a very important tool to analyze the dynamic properties of Petri nets, but the concurrent relation of transitions in Petri nets cannot be represented by reachability graph. Petri net is a concurrent system, while reachability graph is a serial one. However, concurrency is a kind of property which is not only very significant but also difficult to be analyzed and controlled. This paper presents the concepts of concurrent reachable marking and concurrent reachable graph in order to represent and analyze the concurrent system. The algorithm constructing concurrent reachable marking set and concurrent reachability graph is also shown so that we can study the response problems among services in a network computing environment and analyze the throughput of the system. The Dining Philosophers Problem, which is a classic problem of describing the management of concurrent resources, is given as an example to illustrate the significance of concurrent reachability graph.

Integrated Assembly Structure Design Within Concurrent Engineering

Taking a microwave product as an example, a system of integrated assembly structure design is presented. Getting design constraints from the upstream design section through product data management(PDM), the system generates the assembly scheme using the case? based method, then assigns the design requirements into each component of the assembly. The detail design for each component can be performed under these design constraints. In order to practise concurrent design, the system sends the final design result to the upstream section and downstream section through PDM to achieve information sharing and integration.

QUANTITATIVE APPROACH TO REAL TIME STARTUP TIME DETERMINATION OF DOWNSTREAM PHASES IN CONCURRENT ENGINEERING

Implementation of simultaneous execution phases in the concurrent engineering (CE) needs careful planning when the downstream phase could be activated as the upstream phase developed to a certain point. The determination of startup time of overlapping jobs in CE has long been a disturbance in manufacturing industry implementing CE programs. A novel model based on both fuzzy logic and neural network is proposed to mathematically formulate the inter-connective information between the two coupled phases in CE projects, and to determine the startup time of downstream phases in real time. The information transferring between the two coupled phases is quantified by using the negative Shannon entropy. Based on this algorithm, a PDM-based framework is proposed to narrow the gap between pro-duct design and manufacture, in which five modules are built to monitor, reshuffle and implement the simultaneous executing processes. Finally, an example is given to illustrate applications of the algorithm in the real world.

Effect of concurrent precipitation on recrystallization textures in commercial Al-Mn alloys

The effect of concurrent precipitation on recrystallization textures in AA 3003 aluminum alloys was investigated using X-ray diffraction and electron backscattering diffraction（EBSD） analyses. A weak recrystallization texture was observed in the AA 3003 alloy annealed at 783 K due to the high annealing temperature. Under the same conditions, extremely high P {011 } （ 111 ） recrystallization textures were detected in the AA 3003 alloy added with 0. 39% Sc. Based on the EBSD results, no intensely preferential orientation nucleation of recrystallization grains was observed in the early stage of recrystallizafion for both alloys. However, concurrent precipitation strongly retarded the growth of recrystallization grains, except for P nucleation sites, thereby conferring an apparent initial growth advantage for P nucleation sites compared with other nucleation sites. Therefore, a sharp P {011 } 〈 111 〉 texture appeared in concurrently precipitated AA 3003 alloys.

Process Environment Oriented Concurrent Tolerance Analysis

Tolerance analysis is investigated under an environment of concurrent design in order to lead to optimized tolerance, as traditional tolerance analysis is often inefficient and liable to mistakes. Making full use of knowledge in manufacturing tolerance analysis combined with the beta distribution model is introduced and applied. The use of beta distribution reflects fully actual capabilities in manufacture. Concurrent tolerance design is a manufacturing environment oriented design process paying more attention to influences or restraints on product design caused by such factors as the manufacturing process, machine capabilities, economy in manufacturing, etc. Process environment oriented tolerance analysis is more flexible making the designed results more practical and effective.