Net Tool Research Articles

Sizing Up the Farm Bill Safety Net

Lower commodity prices and higher production costs over the past couple of years have crop producers concerned about tighter margins and cash flow for their operations. The federal farm income safety net provides substantial support to producers through commodity programs, crop insurance programs, and disaster assistance. Crop insurance has been the primary safety net tool for producers in recent years as commodity prices generally fluctuated at levels above commodity program support levels. Even declining markets in the past couple years left prices that remained above Price Loss Coverage (PLC) support levels and revenue calculations above Agriculture Risk Coverage (ARC) guarantees unless there were significant yield losses at the county level for ARC-CO or the individual farm level for ARC-IC. The outlook is changing however as declining prices run into support levels that are increasing based on the past few years of higher prices. The ARC program provides a revenue guarantee tied to 86% of a benchmark revenue calculated from a five-year moving average price and a five-year moving average trend-adjusted yield. The PLC program provides support if prices fall below the higher of a legislated reference price or 85% of a five-year moving average price. With the higher prices experienced during the past few years, the five-year moving average price has increased and both ARC and PLC support levels have gotten stronger. A look at ARC and PLC protection and payment levels provides a picture of what current support and cash flow may look like and what future support could be under current or future farm legislation.

A novel fault detection and diagnostic Petri net methodology for dynamic systems

Faults can have significant, negative impacts on the operation and performance of simple and complex dynamic systems. Based on the integration of Bayesian network diagnostic features with Petri net formalism, the existing Bayesian-supported Petri net tool has demonstrated the flexibility of using the Petri net approach for diagnosing failure scenario of a dynamic system. However, studies on using the proposed hybrid Petri net approach for condition monitoring and early detection and diagnosis of single and multiple failures in a dynamic system with feedback control loops are yet to be investigated. Thus, this paper presents a methodology to address this research gap using the operation of a water tank level control system as a case study. The method combines the constructed Generalised Stochastic Petri Net (GSPN) model of the system operation with its corresponding fault diagnostic Petri net model, created using the proposed modified Bayesian Stochastic Petri Net (mBSPN) formalism. The GSPN model establishes the causal relationships between the system’s components and/or subsystems. It further identifies deviations in the sensor measurements of the observable process variables characterising the system operation. The information provided by the sensors in the system model are then inputted into the mBSPN model to diagnose the root cause of the observed deviations. The obtained results demonstrated the capability of using the proposed integrated Petri net methodology for system condition monitoring, early fault detection and diagnosis of single and multiple failures in a dynamic system with feedback control loops.

Short Communication: The biodiversity of aquatic organisms in Anak Laut Lake, Aceh Singkil District, Indonesia

Abstract. Muhtadi A, Leidonald R, Yolanda O, Harahap R, Matondang NP, Putri K, Simamora LFM, Sitompul G. 2023. Short Communication: The biodiversity of aquatic organisms in Anak Laut Lake, Aceh Singkil District, Indonesia. Biodiversitas 24: 4837-4844. Anak Laut Lake is a unique and strategic coastal lake, significantly recognized for its diverse marine biota and the potential to be a spawning, nursery, and feeding ground. Therefore, this research aimed to determine the types of aquatic organisms, including plankton, fish, crustaceans, benthos, seagrasses, and mangroves in Anak Laut Lake. The experiment was conducted in October 2022 in the Anak Laut Lake ecosystem, North Singkil Sub-district, Aceh Singkil District, Aceh Province, Indonesia. The plankton was taken using a plankton net tool, extracted vertically from a depth of 2 m, and pulled to the surface. Fish and crustaceans were observed and caught with purse seines, ring nets, and gill nets. Benthic organisms were directly observed on the edge of the lake, along with the identification of mangroves, while at the bottom, the fishermen dove into the water. The data obtained were analyzed descriptively and compared with similar research. The results showed a rich biodiversity in Anak Laut Lake, with at least 165 species/genera of aquatic biota, 9 species of mangroves, and 2 Seagrass species. The marine nekton found consisted of fish (55 species), shrimp (3 species), and crabs (10 species). The macrozoobenthos found in Anak Laut Lake consisted of 13 species of clams, 12 gastropods, 3 sea cucumbers, 2 sand dollars, 2 horseshoe crabs, and 1 sea urchin. Various species of aquatic biota whose existence was threatened in nature and found in this lake included golden sea cucumber (Stichopus herrmanni), seahorse (Hippocampus comes and Hippocampus kuda) with Vulnerable status (VU), tap ray (Maculabatis gerrardi), and sand cucumber (Holothuria scabra) with Endangered species status (EN). This shows that this coastal lake is an important and crucial habitat for several species that are vulnerable to extinction. For this reason, in the future, further studies are needed regarding the habitat characteristics and spatial and temporal distribution of aquatic organisms in Lake Laut, so that more appropriate management can be implemented for the sustainability of the lake.

.NET Tools for Software Development: Tool Selection, Key Benefits of .NET Web Applications

Aims: This report analysis the top 5 .NET tools that can be used to develop website and software.
 Study Design: We have shortlisted the 5 .NET tools that can be used to design and implement website and software.
 Methodology: According to Microsoft, .NET is a software-based approach for integrating information, users, technologies, and devices, and it encompasses everything that an organization requires to build and deploy an integrated data architecture: servers used to host services; development tools; and apps that utilize them. We have selected Web essential for Visual studio, Resharper, Ncrunch, NuGet and Elmah tools.
 Results: The exposed qualities connect to modern emerging techniques such as components, allocation, software and services, and online redirection. As a result of the available options, .NET is recognized as one of the most extensively used software development platforms. The framework .NET's of devices and technologies as well as their optimal usage in practice, need knowledge with its tool set.
 Conclusion: The NET-framework offers a variety of software types, with a focus on producing apps for Windows, mobile devices, and the Internet. Windows applications can be terminal (text-based) or graphical, including drivers, libraries, and services. Applications for mobile devices are created for smartphones and tablets. ASP.NET web services and web applications written for the Internet.

A Formal Performance Evaluation Method for Customised Plug-and-Play Manufacturing Systems Using Coloured Petri Nets.

Recent technological advancements and the evolution of industrial manufacturing paradigms have substantially increased the complexity of product-specific production systems. To reduce the time cost of modelling and verification and to enhance the degree of uniformity in the modelling process of system components, this article presents a componentised framework for domain modelling and performance analysis based on the concept of “multi-granularity and multi-view” for a production line of personalised and customised products, for plug-and-play manufacturing processes to involving a large number of model input parameters. The coloured Petri net tool is utilised as a simulation tool for mapping domain models to computational models for simulation and performance evaluation. This paper presents a method for setting the input parameters of a production system when using WIP, through-put and cycle time as metrics. The results of the performance analysis demonstrate the applicability of the proposed framework and provide direction for the production line’s layout design and scheduling strategy.

PIPE 2.7 overview A Petri net tool for performance modeling and evaluation

The Petri net modeling formalism allows for the convenient graphical visualization of system models, as well as the modeling and performance analysis of complex stochastic systems. PIPE is an open source, platform independent tool for creating and analysing Petri nets including GSPNs (Generalized Stochastic Petri Nets). It is implemented entirely in Java and provides an easy-to-use graphical user interface that allows creating, saving and loading of Petri as well as its qualitative and quantitative analysis. This paper describes PIPE 2.7, its main features, including its GUI, modeling power, and analysis functionality.

Industrial Control Systems Honeypot: A Formal Analysis of Conpot

Technologies used in ICS and Smart Grid are overlapping. The most discussed attacks on ICSs are Stuxnet and Black energy malware. The anatomy of these attacks not only pointed out that the security of ICS is of prime concern but also demanded to execute a proactive approach in practicing ICS security. Honeypot is used to implement defensive measures for security. The Honeynet group released Honeypot for ICS labelled as Conpot in 2013. Though the Conpot is low interactive Honeypot, it emulates processes of different cyber-physical systems, typically Smart Grid. In the literature, the effectiveness of Honeypot operations was studied by challenging limitations of the existing setup or proposing new variants. Similar approaches are followed for Conpot evaluation. However, none of the work addressed a formal verification method to verify the engagement of Honeypot, and this makes the presented work unique. For proposed work, Coloured Petri Net (CPN) tool is used for formal verification of Conpot. The variants of Conpot are modelled, including initial state model, deadlock state model and livelock model. Further evaluation of these models based on state space analysis results confirmed that Conpot could lure an attacker by engaging him in an infinite loop and thereby limiting the scope of the attacker from exploring and damaging the real-time systems or services. However, in the deadlock state, the attacker’s activity in the conpot will be restricted and will be unable to proceed further as the conpot model incorporates deadlock loop.

Transformation of sequence diagram to timed Petri net using Atlas Transformation Language metamodel approach

AbstractReal‐time systems are complex and composed of time‐bounded events that must satisfy the real‐time constraints for their proper functioning. To cope with the complexity of real‐time systems, model‐driven approaches such as model‐driven architecture (MDA) can be followed, which uses the conceptual models for system representation. This paper presents an MDA‐based automated approach for an early stage performance evaluation and verification of a real‐time system using the Unified Modeling Language (UML)/Modeling and Analysis of Real‐Time and Embedded systems (MARTE) sequence diagram. A metamodel‐based model‐to‐model transformation technique is used for mapping the UML/MARTE sequence diagram into the generalized Petri Net Markup Language (PNML) representation of the timed Petri net model using Atlas Transformation Language (ATL). The derived PNML representation has the advantage to support the interoperability between different Petri net tools when compared over the existing methods that produce tool‐specific representation. The proposed approach enables the system designers to create and evaluate alternate system designs and predict their behavior, contributing to improving the system quality. The contribution of the proposed technique for identifying the optimal system design is analyzed using a real‐time embedded sensor application. The proposed transformation approach is also validated using a real‐time system from the manufacturing domain.

A comparative study of strategies for identifying credible sources of mental health information online: Can clinical services deliver a youth-specific internet prescription?

Adolescents and young adults undertake internet searches before and after attending mental health consultations, but they express concerns about how they can identify reliable online mental health information (OMHI). This action research project examines how clinicians might direct young people towards credible OMHI by analysing which search strategies are most helpful for developing an 'internet prescription' targeted at a youth audience. Recently qualified doctors undertook searches for OMHI about the diagnosis and treatment of seven mental health conditions. Rankings of websites in search results were compared with reliability and quality ratings derived from established evaluation instruments [the Brief DISCERN and the 12-item Health on the Net (HoN) tool]. Of 140 websites identified through seven Google searches, only 15% of those evaluated were categorized as high quality. About 17% of websites were selling a treatment or service and about 25% were regarded as untrustworthy. Also, higher rankings in the search results were not indicative of better quality OMHI (Wilcoxon signed rank test: Z=-5.28; p < .001). Although the HoN and DISCERN tools provided useful insights into the credibility of OMHI, investigators did not think either instrument could be recommended for independent use by youth. Our findings suggest that clinical services should take responsibility for identifying a range of credible sources of OMHI. The next step in translating the research strategy into clinical practice involves collaboration with young people to select those platforms most orientated to their needs and to develop rating instruments that enable youth to evaluate OMHI.

Biological Aspects of Keperas Fish (Cyclocheilichthys apogon) in Batutegi reservoir, Tanggamus Regency, Lampung Province

The research aims to analyze several biological aspects of the squeezed fish in Batutegi Lampung Reservoir. The study used an experimental method of capture used net capture tool with mesh-size 1.5-2.5 inches. Sample fish measured their total length, weighed in weight, and examined their stomachs to determine what type of food they had. We researched in February, August, and November 2017. The example of keperas fish caught amounted to 415 individuals. Analysis of long-weight relationships showed that February and August were allometrically negative, while November allometric was positive. The condition factor is worth one at each station and month. The eating habits of squeezed fish are plants 50%, fish 15%, insects 10%, worms 9%, phytoplankton 8%, and zooplankton 8%. The growth pattern of fish squeeze in November is isometric and allometric positive due to the development of gonads. The food habits of fish keperas are omnivorous, with the composition according to food availability in the environment.

DICER 2.0: A New Model Checker for Data-Flow Errors of Concurrent Software Systems

Petri nets are widely used to model concurrent software systems. Currently, there are many different kinds of Petri net tools that can analyze system properties such as deadlocks, reachability and liveness. However, most tools are not suitable to analyze data-flow errors of concurrent systems because they do not formalize data information and lack efficient computing methods for analyzing data-flows. Especially when a concurrent system has so many concurrent data operations, these Petri net tools easily suffer from the state–space explosion problem and pseudo-states. To alleviate these problems, we develop a new model checker DICER 2.0. By using this tool, we can model the control-flows and data-flows of concurrent software systems. Moreover, the errors of data inconsistency can be detected based on the unfolding techniques, and some model-checking can be done via the guard-driven reachability graph (GRG). Furthermore, some case studies and experiments are done to show the effectiveness and advantage of our tool.

A Ubiquitous Machine Learning Accelerator With Automatic Parallelization on FPGA

Machine learning has been widely applied in various emerging data-intensive applications, and has to be optimized and accelerated by powerful engines to process very large scale data. Recently, the instruction set based accelerators on Field Progarmmable Gate Arrays (FPGAs) have been a promising topic for machine learning applications. The customized instructions can be further scheduled to achieve higher instruction-level parallelism. In this article, we design a ubiquitous accelerator with out-of-order automatic parallelization for large-scale data-intensive applications. The accelerator accommodates four representative applications, including clustering algorithms, deep neural networks, genome sequencing, and collaborative filtering. In order to improve the coarse-grained instruction-level parallelism, the accelerator employs an out-of-order scheduling method to enable parallel dataflow computation. We use Colored Petri Net (CPN) tools to analyze the dependences in the applications, and build a hardware prototype on the real FPGA platform. For cluster applications, the accelerator can support four different algorithms, including K-Means, SLINK, PAM, and DBSCAN. For collaborative filtering applications, it accommodates Tanimoto, euclidean, Cosine, and Pearson Correlation as Similarity metrics. For deep learning applications, we implement hardware accelerators for both training process and inference process. Finally, for genome sequencing, we design a hardware accelerator for the BWA-SW algorithm. Experimental results show that the accelerator architecture can reach up to 25X speedup against Intel processors with affordable hardware cost, insignificant power consumption, and high flexibility.

PUTRACOM: A Formalism of a Novel Component Model

The composition mechanisms and interactions of current component models are mostly base on port or function calls from other components. However, in both styles, the number of interactions that depend on the number of ports and method calls may increase dramatically. Hence, to avoid such complexity of composing components and coordination of the interaction among them, a component model and policy to provide a separation between the components and coordinating is needed. This study presents a formal specification of a novel component model for discrete-event and non-blocking component-based systems called PUTRACOM. A new component model, named PUTRACOM is presented in this paper. PUTRACOM supports to develop concurrent software systems with discrete-event. PUTRACOM defines components by two essential features; they are the Observer/Observable unit and a computation unit. These two features allow a component to have fixed behavior without any dependency on other components. The components can be composed using a well-defined set of connectors. PUTRACOM has been formally defined based on the well-defined and sound methods like CSP and RTSs. PUTRACOM provides a way to construct components and coordinate them with a well-founded mechanism. The model defines a set of exogenous connectors and an observer/observable unit to encapsulate components and coordination. In order to illustrate the way of component composition in the proposed model, an example of the control system of a refrigerator is used. Moreover, to evaluate its applicability, the example has been implemented in Colored Petri Net (CPN) tools.

Performance evaluation of a carousel configured multiple products flexible manufacturing system using Petri net

This study presents a schematic approach to model, simulate and analyze the overall performance of an FMS, comprising a carousel layout surrounded by manufacturing and assembly cells capable to deliver a variety of multiple products. All manufacturing and assembly cells are consisting of multiple multifunctional production and assembly machines, served by material loading and unloading robots, connected through a material transporting conveyor. Inter-cellular and intra-cellular routing flexibility are employed in the system through production resources operational and breakdown modes. Colored Petri net tools are used to develop a compact, editable and deadlock-free flexible manufacturing system model reveals important information about dynamic behavior and system performance measures e.g.; throughput, mean cycle time, and work-in-process (WIP) with reference to material handling and supply system, production resources reliability and process execution input variables. Variation in input factors namely mean machining and assembly time, material loading and unloading time, number of operations between failure, repair time, parts inter-arrival time, conveyor speed and buffer capacity have shown a substantial effect on the system performance. The results indicate successful applicability of colored Petri net tools for modelling, simulation, and evaluation of carousel configured multiple products flexible manufacturing system. Further, the optimal solution represents a deep relationship between the different production modes and responses to maximize the performance of a carousel configured multiple products FMS.

Formal Verification for Task Description Languages. A Petri Net Approach.

One of the main challenges in verifying robotic systems is its asynchronous interaction with an unstructured environment, observed by imperfect sensors. Autonomous robot systems usually require some language to support task-level control. This paper presents an effective approach to apply formal verification methods for that kind of language. A main contribution of this method is to avoid modeling the robotic system with a specific formalism. The approach translates the task-level control models into a Petri net (PN) based representation. This is used to define new methods to analyze some task properties such as liveness, deadlock-freeness and terminability. The approach has been applied to the Task Description Language (TDL) and it is illustrated by experiments. The final goal is to create new tools within the application development environment to include formal verification as part of the normal software development cycle. The TDL to PN translator uses the Petri Net Markup Language (PNML) as its file format. This format permits interoperability with other Petri net tools that can also be used to analyze the PNs.

Distribusi dan Preferensi Habitat Udang Air Tawar Caridina ensifera Schenkel, 1902 pada Dua Inlet Danau Poso, Sulawesi Tengah

The distribution and habitat preference of freshwater shrimps Caridina ensifera Schenkel, 1902 on two inlets of Lake Poso, Central Sulawesi have been studied. Freshwater shrimps samples was collected in two streams, namely the Pomua Palandu Stream and Toinasa Stream. The sampling station on each streams is divided into three locations based on the distance of the stream flow from its mouth at Lake Poso. Sampling is done by purposive sampling method using the tray net tool. The obtained samples were preserved using 96% alcohol and than identification was carried out at the Laboratory of Animal Biosystematic and evolution, Department of Biology, Tadulako University. The results showed that Caridina ensifera was only distributed in the lower reaches of the Pomua Palandu Stream and Toinasa Stream, having habitat preferences between plant roots that dangled into the water with rocky sand and sand substrates and very slow current speeds. According to von Rintelen and Cai (2009) Caridina ensifera is distributed in Lake Poso.

Performance analysis of hierarchical location management system for mobile-multi-agent system

Location management of a Mobile Agent (MA) is necessary for a Mobile Agent System (MAS), in which many significant services are accomplished using MA communications that require specific location information. This paper gives the performance analysis of a Hierarchical Location Management System (HLMS) for mobile Multi Agent System (MUS) with the objectives to reduce the search and update cost. This work also discusses a mailbox-based approach to provide communication among MAs. Mailbox is a data structure which is used to store the messages for MAs. There are two different communication mechanisms (jump and full migration) with mailbox have been used. In jump migration MA's mailbox always resides at the local router and in full migration MA always carries its mailbox with it at the host it is executing. For jump migration MA periodically checks its mailbox to get the message. HLMS has been modelled using the timed Coloured Petri Net (CPN) tool. Performance of HLMS is then observed for identified parameters such as Trip Time (TT), Migration Rate (MR), Search Rate (SR), Network Overhead (ND) and Communication Time (COT). Simulation results show that HLMS can locate the MAs in a fault free environment but TT and ND decrease as intra-region MR increases.

A Petri Net-Based Heuristic Algorithm for Short-Term Vehicle Scheduling in a Vehicle Inspection System

Vehicle inspection systems (VIS) have been extensively used by automobile manufacturers, maintenance companies, and the traffic administrative departments for the inspection of safety, reliability, and other indicators of both newly produced and in-used vehicles. How to increase their productivity by effectively operating such systems is an interesting and crucial problem. Because of the space limitation of testing field in such a system, a vehicle must complete pre-set inspection items at multiple stations in sequence. Hence, it is very challenging to sequence the vehicles to be tested to shorten the unnecessary waiting time for vehicle testing. This paper investigates the vehicle scheduling problem of such systems, where the time for vehicle movement in the system can be ignored. The system is modeled by resource-oriented Petri net, a graphical and mathematical modeling tool. Based on the model, this work analyzes the testing cycle time and develops a heuristic algorithm to efficiently solve the vehicle scheduling problem in such a system. For the first time, a heuristic algorithm for generating an optimal vehicle queue for testing is proposed. Industrial examples are used to illustrate the proposed algorithm and results show that a significant reduction in total test turnaround time can be obtained in comparison with the existing methods.

Performance analysis of hierarchical location management system for mobile-multi-agent system

Location management of a Mobile Agent (MA) is necessary for a Mobile Agent System (MAS), in which many significant services are accomplished using MA communications that require specific location information. This paper gives the performance analysis of a Hierarchical Location Management System (HLMS) for mobile Multi Agent System (MUS) with the objectives to reduce the search and update cost. This work also discusses a mailbox-based approach to provide communication among MAs. Mailbox is a data structure which is used to store the messages for MAs. There are two different communication mechanisms (jump and full migration) with mailbox have been used. In jump migration MA's mailbox always resides at the local router and in full migration MA always carries its mailbox with it at the host it is executing. For jump migration MA periodically checks its mailbox to get the message. HLMS has been modelled using the timed Coloured Petri Net (CPN) tool. Performance of HLMS is then observed for identified parameters such as Trip Time (TT), Migration Rate (MR), Search Rate (SR), Network Overhead (ND) and Communication Time (COT). Simulation results show that HLMS can locate the MAs in a fault free environment but TT and ND decrease as intra-region MR increases.

Validation of severe accident management guidelines (SAMGs) for advanced power reactor 1400 (APR1400) using colored Petri net (CPN) Tools

Since the Fukushima nuclear accident in 2011, there has been a growing need to strengthen severe accident management guidelines (SAMGs) and find appropriate methods for validating SAMGs. The validation of SAMGs is currently performed in terms of their usability, using a full-scope simulator, a tabletop drill, and a severe accident analysis code. However, given that the use of these rely on human expertise, and the workflow of SAMGs is very complex, a new validation method is needed. In this study, a model of a SAMG workflow has been developed using Colored Petri Nets (CPN) as a new validation method. In addition, time delay, which is required for SAMG actions, has been factored in.In order to verify usable SAMGs instead of existing validations by SAMG documents, the SAMGs were validated using computing technology. The modified CPN models, which are representative of the limited plant states during implementation of SAMGs, were simulated for computer-assisted validation. It has been verified that the novel validation method can complement existing validation methods.