Modeling Of System Requirements Research Articles

Model‐based analysis and specification of functional requirements and tests for complex automotive systems

AbstractThe specification of requirements and tests are crucial activities in automotive development projects. However, due to the increasing complexity of automotive systems, practitioners fail to specify requirements and tests for distributed and evolving systems with complex interactions when following traditional development processes. To address this research gap, we propose a technique that starts with the early identification of validation concerns from a stakeholder perspective, which we use to systematically design tests that drive a scenario‐based modeling and analysis of system requirements. To ensure complete and consistent requirements and test specifications in a form that is required in automotive development projects, we develop a Model‐Based Systems Engineering (MBSE) methodology. This methodology supports system architects and test designers in the collaborative application of our technique and in maintaining a central system model, in order to automatically derive the required specifications. We evaluate our methodology by applying it at KOSTAL (Tier1 supplier) and within student projects as part of the masters program Embedded Systems Engineering. Our study corroborates that our methodology is applicable and improves existing requirements and test specification processes by supporting the integrated and stakeholder‐focused modeling of product and validation systems, where the early definition of stakeholder and validation concerns fosters a problem‐oriented, iterative and test‐driven requirements modeling.

A system modeling process based on SysML to support data consistency across system requirement, function, and solution model layers

Model-Based Systems Engineering (MBSE) is a popular system engineering development method focusing on digital models as the primary mean of information exchange to improve communication across disciplines. To implement MBSE, the system model needs to be created to represent systems at different layers of abstraction, such as requirements, functional architectures, and solution designs throughout the development phase. Although many studies have mentioned the need to pay attention to the traceability between different layers of system models, there is still a lack of an automated system modeling process. This can lead to inefficiencies and even errors during the system modeling process. A semi-automated system modeling process based on Systems Modeling Language (SysML) is presented to overcome the issue. This work elaborates on a formalised modeling mechanism based on SysML elements to aid system engineers in system modeling with a function-oriented architecture. This work demonstrates and evaluates the proposed process by developing a wind turbine (WT) system model. The contribution of this study is that it realizes the semi-automatic top-down system modeling process. This ensures data inheritance and consistency between different system model layers of abstraction. It also reduces manual efforts and improves the efficiency of the system modeling process.

Validation of Industrial Automation Systems Using a Timed Model of System Requirements

Validation of industrial automation systems is the process of checking that commissioner requirements are successfully implemented. Formal approaches are needed when the considered system is critical. The method presented in this article relies on a model-based approach that exploits the compactness and graphical representation of time-interpreted Petri nets, which adds input–output interpretation to transitions/places and embeds time information. These nets are here used with multiple-server semantic to allow effective modeling of typical automation system requirements. The key idea of the system validation approach is to compare the observed behavior of the automation system with the expected behavior, as generated by updating online the model of system requirements using a state estimation algorithm. Also, an off-line procedure is provided to evaluate the evolutions admitted by the model but not observed. Both procedures yield useful data to the validation engineer, allowing to speed up the validation process. Technological issues due to the synchronous nature of controllers and the implications of their programming are considered.

Semantic Modeling and Analysis of Natural Language System Requirements

System requirements specify how a system meets stakeholder needs. They are a partial definition of the system under design in natural language that may be restricted in syntax terms. Any natural language specification inevitably lacks a unique interpretation and includes underspecified terms and inconsistencies. If the requirements are not validated early in the system development cycle and refined, as needed, specification flaws may cause costly cycles of corrections in design, implementation and testing. However, validation should be based on a consistent interpretation with respect to a rigorously defined semantic context of the domain of the system. We propose a specification approach that, while sufficiently expressive, it restricts the requirements definition to terms from an ontology with precisely defined concepts and semantic relationships in the domain of the system under design. This enables a series of semantic analyses, which guide the engineer towards improving the requirement specification as well as eliciting tacit knowledge. The problems addressed are prerequisites to enable the derivation of verifiable specifications. We present the results from a case study of modest size from the space system domain, as well as an evaluation of our approach from the user’s point of view. The requirement types that have been covered demonstrate the applicability of the approach in an industrial context, although the effectiveness of the analysis depends on pre-existing domain ontologies.

An Inductive-ROC Based Model for Determining Purchasing System Requirements

The success of system development studies depends on the completeness and accuracy of the requirements collected from system user and stakeholders. Mistakes and deficiencies in the requirements determination process lie in the failure of many system development studies. The dynamism and complexity of today's systems make the requirements determination process even more complicated, and the requirement determination phase, which is the primary stage of system development studies, gains excellent importance. Although there are many techniques, strategies, and models in the literature to improve the requirements Determination process, there are very few studies on their multiple-use, classification of needs, and their experimental realization in a real system. In this study, a system development study was carried out using the System Requirements Model (SRM), which has a flexible structure that allows the system needs to be determined with the use of multiple techniques, at the same time classifies the identified requirements, can decide on the determination levels, and allows the work to be stopped if a sufficient level of needs is determined The developed model consists of three stages: requirement identification, rulemaking/technical/needs matrix creation and classification of needs. In the needs determination process, collection, presentation, verification, and sort of needs. In the second stage of the model, an analogy was made, and the needs and techniques were grouped with the ROC algorithm, and the rule-based RULES-3 algorithm was used to universalize the model. In the third stage of the model, needs were determined based on technical/technical combinations.

97 Impact of Regionalized Forage Quality and Quantity and Feed Grain Water Use on the Daily Texas Beef Cattle Water Footprint and Supply Chain Efficiency

Abstract Livestock water use sustainability is a growing concern in the beef cattle sector. The Water Footprint Assessment (WFA) method has been used to quantify the water footprint (WF) of beef products but does not suggest any specific management strategies to decrease the WF of beef cattle (WFB) within and across the beef supply chain. The WFB is primarily influenced by forage and grain production water uses (m3/t), which are directly linked to dry matter (kg/d) and water intake (L/d) and cattle growth (kg/d). Therefore, the objective of this study was to assess the alteration of forage quality and above-ground biomass production (t/ha) of annual ryegrass (Lolium multiflorum) and bermudagrass (Cynodon dactylon), in addition to published WF estimates for corn (Zea mays) and soybean (Glycine max) production (m3/t) on the daily Texas WFB. A dynamic Texas Beef Water Footprint Model (TXWFB) was developed to predict WFB, using the System Dynamic methodology and equations from the Ruminant Nutrition System (RNS) and Beef Nutrient Requirements (NASEM) models. Results indicated that forage and crop biomass production is a high-leverage solution to offset the daily Texas WFB (%∆ = -55 to 130). The alteration of forage TDN had less of an impact on the Texas WFB (%∆ = -39 to 17). An ANOVA with a Tukey Posthoc test indicated that all WFB scenarios were significantly different (P < 0.05) except for the low versus base TDN under low water use conditions scenario. The variability in the use of green and blue waters for grains indicated that the final WFB, in the feedlot phase, may be lower than the WFB in the cow-calf or stocker stages under certain efficiency conditions. Identification of high and low-leverage solutions may help Texas cattle stakeholders implement systemic strategies that aid in the efforts for sustainable beef water use.

Multilanguage health record database focused on the active follow-up of patients and adaptable for patient-reported outcomes and clinical research design

IntroductionA dataset with patient information allows a comparison between different clinical treatments in many fields of medicine as well as the effective use of medical resources. Patient-reported outcome measures (PROMs) collect data directly from patients for use in clinical practice by helping decision making and tailoring treatments according to the patients’ needs. The authors present a novel database to overcome data collection related barriers, calculating automatically the questionnaire results, displayed in graphics on the patients’ dashboard in real time, and focused on the active follow of the patients. ObjectiveTo present electronic health record database for monitoring clinical or surgical interventions and assess the usability. MethodologyProcess modeling and specification of system requirements were performed using the Iconix methodology along with the Post-Study System Usability Questionnaire (PSSUQ) to validate the usability and usefulness of the proposed system. The system and the questionnaires were performed in three languages: Brazilian Portuguese, Spanish, and English. ResultsThe database enables researchers to use the questionnaires defining the time of data collection according to the needs of each clinical study. The system facilitates the patient answers without any personal interference from smartphones, tablets or computers. The questionnaire scores were calculated automatically in real time and displayed in graphics on the patients’ dashboard. The evaluation of the usability and usefulness of the developed database used 8 people divided into two equal groups (4 physicians and 4 medical students). ConclusionThe proposed electronic health record database allows a friendly and flexible use of PROMs according to the population, needs in practice and clinical settings. The platform promotes active and direct data collection from patients and physicians in English, Portuguese and Spanish.

Functional Requirements Specification of E-Tendering Using Natural Language Approach: Towards Innovative Business Transformation

Recently, business transformation towards the used of Information and Communication Technology (ICT) is a necessity toward rapid industries and the paradigm shifted to sustain business competitiveness. The holistic electronic approach is one of business innovations, especially in handling a lot of tender documentations and process in an electronic environment namely as e-Tendering. Unfortunately, the existing tender process transformation in the electronic approach is not properly followed certain standard and guideline, especially in establishing a good e-Tendering functional requirements specification to ensure the organizations would be in the best served. This is important to ensure a good e-Tendering system can be developed by e-Tendering developers based on a good e-Tendering functional requirement specifications. The requirements specification is a process of documenting user and system requirements. Commonly, user and system requirements should be clear, unambiguous, easy to understand, complete, and consistent. In practice, this is difficult to achieve due to interpretation of the requirements in different ways by stakeholders, which are often inherent conflicts and inconsistencies of the requirements. The implementation of the existing e-tendering still remains uncertainties, especially in defining the functional requirements of the e-tendering system. Therefore, this study aims to construct the e-Tendering functional requirement model using requirement template in natural language representation approach. Moreover the development of this system requirement model may provide a consistency to the requirements representation. The study uses UN/CEFACT Business Standard of the e-Tendering Business. The identified functional requirements are designed by using Requirement Template to ensure the reliability and understandability of requirements. Besides, the proposed functional requirements is constructed by adapting the natural language and verified by expert review approaches. As a result, this study proposed a functional requirements specification of the e-Tendering that contains detailed description which can be referred by software practitioners in developing a secure e-tendering system effectively.

Evaluation of Enterprise Resource Planning System Based on SAP Module of Material Management Procurement Function in PT. Kimia Farma Tbk

The purpose of this study is to evaluate and analyze solutions for problems that identified in the Enterprise Resource Planning SAP based on system Material Management Module on Procurement Function in PT. Kimia Farma Tbk. The evaluation method is fit gap analysis Architectural Approach based on FURPS System Requirement model. The Procurement processes included in this study are Create Purchase Requisition, Create Request for Quotation, Maintain Quotation, Create Purchase Order, Create Goods Receipt and Create Service Entry Sheet. The results in this study are presented as a recommendation to fix the problem based on the evaluation result.

SFMEA assistant design method for control system using requirement modeling

Software Failure Modes and Effects Analysis (SFMEA) is an effective reliability analysis technique which is widely used in control systems. However, it is difficult to analyze the failure mode using traditional SFMEA method, as control system becomes more complicated. This paper proposed an assistant design method of SFMEA based on system requirement model, which would remedy the deficiencies in analyzing complex control system. An experiment shows that this method can be applicable to SFMEA for complex control system.

Model-Based Dependability Analysis of Physical Systems with Modelica

Modelica is an innovative, equation-based, and acausal language that allows modeling complex physical systems, which are made of mechanical, electrical, and electrotechnical components, and evaluates their design through simulation techniques. Unfortunately, the increasing complexity and accuracy of such physical systems require new, more powerful, and flexible tools and techniques for evaluating important system properties and, in particular, the dependability ones such as reliability, safety, and maintainability. In this context, the paper describes some extensions of the Modelica language to support the modeling of system requirements and their relationships. Such extensions enable the requirement verification analysis through native constructs in the Modelica language. Furthermore, they allow exporting a Modelica-based system design as a Bayesian Network in order to analyze its dependability by employing a probabilistic approach. The proposal is exemplified through a case study concerning the dependability analysis of a Tank System.

Supporting the Formal Analysis of System Requirements Model

Supporting the Formal Analysis of System Requirements Model

Decision quality by the loss cost of Type I and Type II errors

PurposeThe purpose of this paper is to explore the system requirements model. According to the concept of loss costs of Type I and Type II errors, it can define the optimal decision line, and reduce overall loss costs. Moreover, it can decrease the probability of Type I and Type II error by the systems thinking, and it can effectively reduce overall loss costs.Design/methodology/approachThe paper proposed a system demand model and constructed a decision‐making system thinking model as well as a decision‐making performance management model using the principle of system demand. Types of decision‐making errors were analyzed to set judgments on the error risk and establish a model of improvement evaluation key factors, in order to reduce decision‐making error risk and enhance decision quality. It also constructed the improved decision‐making to assess the key factors, to reduce the risk of making errors in order to improve the quality of decision‐making.FindingsOptimistic decision‐makers (risk takers) tend to make Type II errors, whereas pessimistic decision makers (conservatives) tend to make Type I errors. Financial depressions are the time for optimistic decision makers (risk takers) and boom periods are the time for pessimistic decision makers (conservatives).Originality/valueThe concept of the loss cost of two decision‐making errors and related cost function models were proposed. Decision makers could make decisions with a more stable model, taking into consideration false alarms and the cost function of errors in order to determine the position of the decision‐making line. It could effectively reduce decision‐making error costs and increase the precision of decision‐making.

Prototyping System Requirements Model

In this paper, we present a tool for automatic prototype generation and analysis (AutoPA2.0) that implements the transformations from UML system requirements models to executable prototypes with the function of checking multiplicity invariants. A UML system requirements model consists of a use-case model and a conceptual class model. Generally, a use case is either described as a system operation which can be defined as a pair of pre and post conditions in the context of the conceptual class model, or described as a sequence of such system operations. AutoPA2.0 can transform the descriptions of use cases into an executable prototype in Java. The execution of each use case is a sequence of basic atomic actions which first check the pre-condition and then enforce the post-condition of the corresponding use case. It helps to improve the understanding between customers and designers. A simple library system is used to explain the method, and illustrate the feasibility of tool as well as its development.

Integration of different system engineering methods using an object-oriented model

The development of large, complex systems consisting of both hardware and software normally involves several companies and/or development teams for the development of the different subsystems forming the entire system. Depending on the kind of subsystem to be developed, these different development teams normally use different system engineering methodologies and/or tool sets to produce their subsystems. However, the usage of different methodologies and tools makes technical management and quality assurance for the entire development effort a difficult task. Therefore the development as well as the maintenance of future systems with their increasing size and complexity requires a common frame for the entire system development and maintenance effort covering different kinds of subsystems, like graphical user interfaces, database systems, expert systems, real-time systems, and so on. This common frame should support the separate and independent development of the different subsystems by different subcontractors using different system engineering methods, the integration of these subsystems to the entire system as well as the maintenance of the entire system. A hierarchical object-oriented model for the encapsulation and integration of different system engineering methods can serve as this common frame, providing traceability from the system requirements model to the implemented system while giving each subsystem development team full scope in choosing the system engineering method most suitable for a specific subsystem. The approach underlying this object-oriented model is the encapsulation of the different subsystems in “high-level objects,” which can be either further decomposed into “high-level object” or described in more detail using any appropriate system engineering method. The integration of these “high-level objects” to the entire system is supported by a “definition object” on each layer of each system engineering models and the different “high-level objects.”