Performance evaluation of MiniMAP networks

Design and implementation of an MMS environment on ISODE

The manufacturing message specification (MMS) is an application layer protocol (ISO IS 9506) which specifies services for distributed manufacturing applications design. It enables communication between heterogeneous devices. An important topic in application design process is the performance issues, because some applications present performance constraints such as maximal service response time. This paper presents some performance models for evaluating the MMS response time by taking into account among others the real characteristics of a MAP/MMS implementation. Colored stochastic Petri nets formalism was used for models representation on the one hand and simulation for their resolution on the other hand. This choice has been established following the analysis of characteristics of MMS. We have built our models in a progressive way until we obtained the global MMS model. The major problem posed in this work, is the lower layers' model parameters. These parameters are mainly probability distributions of processing time for each network layer. These distributions are different and specific to each implementation. Their determination is necessary for the quantitative validation of the models. However these indices are inaccessible in the used implementation. To show the behavior of our models, we have therefore put forward hypotheses on the various missing indices.

This paper addresses the problems concerning the fault-tolerant distributed replication of a controlling application in an automated system. The Manufacturing Message Specification (MMS) is used as a communication protocol between the controlling application (MMS client) and the automated industrial equipment (MMS servers). A distributed systems toolkit (DST) is used to manage the replication of the controlling application. We identify potential obstacles in the MMS environment when passive client replication is used. We suggest methods that the recovering client can use to overcome these obstacles. The solutions and alternatives proposed are discussed with respect to their conformance to the MMS standard.

The implementation of an icon-based manufacturing message specification (MMS) messaging system for system control in a manufacturing automation protocol (MAP environment) is described. The system was designed with a four-layer hierarchy. The top layer acts as a user interface and essentially provides a data manipulation service. The next layer invokes the appropriate firmware calls to manage the communication process. The third layer consists of the firmware that handles the actual transmission of data across the network. The lowest level is the actual network hardware. Twelve MMS services were implemented in order to provide the capability to carry out a typical control session. The system was tested using software that simulates the external communications of an MMS virtual manufacturing device. The LabVIEW MAP environment used imposed at least two limitations on the operation of the system. First, LabVIEW makes no provision for data structures; therefore, each parameter had to be passed from the MMS layer to the code VI layer as a variable of a specific data type. Second, LabVIEW provides no convenient way to maintain global variables throughout a diagram. >

ATM switches are now being designed to allow connections to be partitioned into priority classes, with packets being emitted for higher priority classes before packets are emitted for lower priority classes. Accordingly, allocation of network resources based on different priority levels is becoming a realistic possibility. Thus, we need new methods for connection admission control and capacity planning that take account of the priority structure. We show that the notion of effective bandwidths can be used for these purposes when appropriately extended. The key is to have admissibility of a set of connections determined by a linear constraint for each priority level, involving a performance criterion for each priority level. For this purpose, connections are assigned more than one effective bandwidth, one for its own priority level and one for each lower priority level. Candidate effective bandwidths for each priority level can be determined by using previous methods associated with the first-in first-out discipline. The proposed effective bandwidth structure makes it possible to apply product-form stochastic loss network models to perform dimensioning.

IEC 61850 is an international standard developed by the International Electrotechnical Commission TC57 substation automation communication networks and systems. It uses MMS (Manufacturing Message Specification) as a real-time communication protocol of the application layer, and achieves the communication between the substation layer and the spacer layer. This paper describes the features and functions of the IEC 61850 and MMS technology and focuses on the principle of MMS mapping in the application of IEC 61850 , then preliminarily leads to the overall design framework of the IEC 61850 gateway.

We introduce a specification of a distributed transaction processing facility for the Manufacturing Message Specification (MMS) which is an application service element of the Manufacturing Automation Protocol (MAP) standardized by the International Standard Organization (ISO) to support messaging communication to and from programmable devices in a computer integrated manufacturing (CIM) environment. The proposed facility permits the organization of a distributed transaction in terms of a set of MMS services encapsulated together to perform the manufacturing or the production tasks. The services provided by the transaction processing (TP) standard, presented by the ISO, are used as well as new services are defined to guarantee the coherent behavior of the MMS distributed transactions. This guarantee is based on the satisfaction of the Atomicity, Consistency, Isolation, and Durability (ACID) properties defined by the ISO. The distributed transaction processing facility is specified as finite state automata represented by Nutt evaluation networks notations. A validation technique based on the Calculus of Communicating Systems (CCS) introduced by Milner is used to prove the coherent behavior of the transactions.

Manufacturing equipments should be integrated to construct CIM (Computer Integrated Manufacturing) environment, but several economical and technological difficulties may be arisen in case heterogeneous systems are integrated into each other. MMS (Manufacturing Message Specification) can be effective in such a case, but the problem is that MMS-related products are comparatively expensive and the existing manufacturing equipments mostly do not support MMS. This study was focused on developing a gateway suitable to a non-MMS-compatible CNC machine-tool, and on implementing OSI (Open System Interconnection) upper layer on TCP/IP. The development system was applied to a cell controller by means of heterogeneous equipments under CIM environment, and to evaluate interoperability and portability.

In March of 2020, elective surgical procedures in New York State were suspended in response to the COVID-19 pandemic. At Northwell Health, this lasted a total of 8 weeks, leaving plastic surgeons responsible for recording and rescheduling delayed procedures. Many plastic and reconstructive procedures are considered elective, but these procedures can be time sensitive, and delays can have a negative impact on patient care.1 Our goal was to compare the rates of completion and time to completion between different priority groups and procedure types in order to predict potential consequences for one's practice if future suspensions in elective surgery were to occur. We hypothesized that procedures grouped in the reconstructive categories with higher priority levels would have a higher completion rate and lower time to completion compared to less urgent, aesthetic based procedures. Plastic surgeons working for our department were responsible for keeping track of their suspended cases between March 23, 2020, and May 19, 2020.2,3 Under the discretion of the attending plastic surgeon, cases were categorized into procedure type, priority level, and surgery setting. The procedure types included aesthetic, pediatrics/craniofacial, hand, general, and reconstructive. The priority classes were elective, nonurgent, semiurgent, urgent, and emergent. The surgery setting was classified into inpatient and outpatient. In total, we examined 135 surgical cases that were suspended (Table 1). The average patient age was 45.8 years, and 45.9 percent of the surgical procedures were completed by the end of August of 2020, more than 3 months after the suspension was lifted. Of those that were completed, the average time to completion from the original surgical date was 79.2 days. Surgery classifications are summarized in Table 1. We ran binary logistic regressions that showed no significant correlation between the surgery type, urgency, or priority class and whether or not the surgery was completed. In addition, linear regression analyses did not show a significant correlation between the surgery type, urgency, or priority class and the time it took to complete the surgery. All the models controlled for patient age and whether or not there was malignancy. Table 1. - Summary of Sample by Procedure Priority Procedure Classification No. of Patients Percent of Sample Priority Elective 8 5.93% Nonurgent 80 52.29% Semiurgent 22 16.30% Urgent 24 17.78% Emergent 1 0.01% Type Aesthetic 12 8.89% Pediatrics/craniofacial 10 7.41% Hand 9 6.67% General 35 25.93% Reconstructive 68 50.37% No type specified 1 0.74% Location Inpatient 34 25.19% Outpatient 66 48.89% No location specified 35 25.93% Our surprising results may be due to several factors, including differences in patients' concerns with undergoing surgery during a pandemic, patients' continuous desire to undergo aesthetic surgery, or a lack of prioritization of urgent cases when rescheduling surgery. With new variants of SARS-CoV-2 emerging and the number of COVID-19 cases climbing rapidly in the United States,5 plastic surgeons must be prepared for another potential suspension of surgery.6 Plastic surgery departments and private practices can use our experience to guide their recovery from future surgical suspension. Prior studies have already shown the tremendous economic impact of surgery delays on plastic surgeons.4Additional research is needed, however, to evaluate the impact of delays on patient care and quality of life. A more systematic approach to rescheduling surgery, which prioritizes the most vulnerable patients, is needed. DISCLOSURE The authors have no relevant financial disclosures to report.

A Distributed Real-Time Transaction Processing Environment For the CIM Applications

14 - UCA protocol

An application of Artificial Neural Networks (ANN) to the substructure detection, from infrared spectra, of organic compounds is described. Several ANNs have already been implemented for this purpose, and show promising initial results; however, many problems remain to be resolved. We wished to train ANNs to assist in a decision support system using several spectroscopic methods to elucidate the structure of unknown molecules. To optimise the ANN with respect to spectral feature extraction, network architecture, training regime and threshold determination, we have investigated several indices for use in the evaluation of network performance. Since much published work on ANN application in this field present performance indices that are poorly defined or of limited use, we recommend that the basic results be reported so that readers may calculate indices to suit their own particular needs. These basic quantities are identified and a set of derived indices recommended.

A PROPOSAL FOR A DISTRIBUTED REAL TIME OPERATING SYSTEM SUPPORTING THE CLIENT/SERVER CONCEPT

This paper presents the critical issues of optical network design and performance evaluation. The performance evaluation of the networks is measured in terms of packet loss probability or throughput with least amount of propagation time (delay). But as the network size grows it becomes cumbersome and hence some mechanism is required to handle stringent requirements of networks. This has been shown that the performance of a network can be significantly improved by partitioning the full networks into smaller sub-networks, which also reduces the spare capacity of the links which are more frequently used in the network.

The authors present a control loop cell architecture based on distributed control using a manufacturing network. The information system handles quality management over this architecture. Quality management in the flexible cell is introduced, and the quality control loop architecture is defined. The flexibility requirements are specified. The information system structure is developed by means of entity-relationship diagrams and their metamodel. The manufacturing message specification is used to realize distributed control and to take into account the entire quality information. An application developed in the laboratory is described. >