Computer-aided Software Engineering Research Articles

Influences of the mesh in the CAE simulation for plastic injection molding

Abstract Although computer-aided engineering (CAE) software has been used for many years in the plastic industry, identifying the most appropriate mesh geometry and density remains a challenge. It can affect the accuracy of the simulation, the time and the costs. The evaluation of the most suitable mesh is not easy because the difficulties to obtain the real the values of the pressure and temperature inside the mold. The current work investigates this issue. A mold was manufactured and sensors were installed in its interior. CAE simulations using different mesh geometries and densities were evaluated against the experimental data. The results showed that the computational time was mostly influenced by the mesh geometry. The use of 2D mesh and lower density can lead to a faster and more precise simulation of pressure inside the mold and 3D mesh with lower density can provide a faster and precise simulation of the temperature.

Transient Thermal Analysis of Welding Fixtures Design

This paper presents the design and analysis of welding fixtures based on transient thermal analysis. Welding fixtures is designed to hold and support the workpiece securely during the welding process. The heat transformation from the workpiece could lead the temperature rises and impacts to the welding fixtures. Therefore, the study introduces the development of welding fixtures as one of a safety measure prevents the welder from injury while handling welding process. The conceptual design of welding fixtures and material were applied to conduct the simulation. Transient thermal analysis was performed on temperature and total heat flux by using computer aided engineering software. The result shows the analysis of equivalent stress, total deformation, factors of safety, fatigue life and fatigue damage. Furthermore, the equivalent stress failure theory used to predict yielding in welding fixture design. The design of welding fixtures and material selection were proposed to hold and support the workpiece securely.

Modeling and validation of the effects of processing parameters on the dimensional stability of an injection-molded polypropylene plate

There has recently been a growing amount of interest in developing process control methods to maintain consistent part quality during injection molding. Some commercially available control methods are believed to offer improved machine and process capability in order to achieve this goal. Regardless of these advantages, however, these methods typically require considerable experimentation before an optimal process setting can be obtained for a particular case. Therefore, a more systematic scheme that does not require extensive experimentation, which in turn costs time and money, is needed. Computer-aided engineering (CAE) is considered to be a good tool for predicting the flow behavior in the cavity during the filling and post-filling stages. If CAE software can accurately predict a part quality indicator, such as one concerned with the dimensional stability, under a given process condition, time-consuming experimentation would no longer be necessary to determine the relationship between the process conditions and part quality. However, the relationship between the process conditions and part quality indicators, such as the dimensional stability, is highly nonlinear and takes no explicit form. The goal of this study is to use CAE tools to establish such a relationship and generate part quality data based on predictions. A second-order regression model is established in order to correlate the part quality with four key process variables using an optimization technique. Finally, we obtain the reference values under these process conditions. A case study was conducted using both a simulation and experimentation for a plaque-shaped piece of polypropylene. The results indicate reasonable agreement between the simulation and experimentation.

Analysis on Software Project Planning and Control Using Case Tools

In software ventures, we go through the progression of issues in arranging and dominant procedure. To avoid all these Strategic Management Process (SMP) is used to recognize and measure risks. The programming joint checking arranging and undertaking for all sided quality that uses circulation capacities in aggregate manner for delivering message alarm which will be very normal for hazard factor. First step to away form the risks of are arranging and controlling, which helps the product designs by overseeing the nature of programming venture as well as to create chance free programming items, subsequent to distinguishing the hazard. Each module can be checked in Programming venture to detecting quality in many-sided quality at major level. Assessing the hazard by positioning the product and observing the imperative exercises of programming venture director is one answer for take care of the issues. CASE apparatuses (Computer-Aided Software Engineering) are an arrangement of use devices and programming framework techniques with the coveted final product of superb, deformity free, and viable programming items. CASE instrument likewise allude to improvement of data frameworks techniques together with computerized apparatuses which is utilized as a part of the product venture advancement process. In CASE instruments, PC based help is utilized by engineers keeping in mind the end goal to create and keep up the product ventures. CASE apparatuses likewise empower programming designers to turn out from the genuine complexities of code when taking a gander at the complex endeavors. This paper presents programming wanders organizing and control threats. With offer assistance of CASE devices the threats are recognized, orchestrated and controlled in the item wanders. This paper furthermore improves the capability and lessens the danger in the framework.

The use of artificial neural networks for extracting actions and actors from requirements document

ContextThe automatic extraction of actors and actions (i.e., use cases) of a system from natural language-based requirement descriptions, is considered a common problem in requirements analysis. Numerous techniques have been used to resolve this problem. Examples include rule-based (e.g., inference), keywords, query (e.g., bi-grams), library maintenance, semantic business vocabularies, and rules. The question remains: can combination of natural language processing (NLP) and artificial neural networks (ANNs) perform this job successfully and effectively? ObjectiveThis paper proposes a new approach to automatically identify actors and actions in a natural language-based requirements’ description of a system. Included are descriptions of how NLP plays an important role in extracting actors and actions, and how ANNs can be used to provide definitive identification. MethodWe used an NLP parser with a general architecture for text engineering, producing lexicons, syntaxes, and semantic analyses. An ANN was developed using five different use cases, producing different results due to their complexity and linguistic formation. ResultsBinomial classification accuracy techniques were used to evaluate the effectiveness of this approach. Based on the five use cases, the results were 17–63% for precision, 5–6100% for recall, and 29–71% for F-measure. ConclusionWe successfully used a combination of NLP and ANN artificial intelligence techniques to reveal specific domain semantics found in a software requirements specification. An Intelligent Technique for Requirements Engineering (IT4RE) was developed to provide a semi-automated approach, classified as Intelligent Computer Aided Software Engineering (I-CASE).

CAD TOOLS AND FILE FORMAT PERFORMANCE EVALUATION IN DESIGNING LATTICE STRUCTURES FOR ADDITIVE MANUFACTURING

Additive manufacturing has opened the door to the creation of lightweight lattice structures. However, present Computer-Aided Design (CAD) and Computer-Aided Engineering (CAE) software are unsuitable for these types of structures. The objective of this research is to examine the performances of current CAD and CAE software to design lattice structures and to demonstrate their limitations and propose requirements for future developments. A performance evaluation of a case study for lattice structure designs was conducted. The criteria used for the evaluation were CAD human-machine-interface, RAM consumption, data exchange between CAD, CAE and CAM tools and finite element analysis (FEA) duration and file sizes. The CAD tool was incapable of executing a repetition function for octet-truss lattice structures of 150 x 150 x 150 mm dimensions or larger and the software stopped working. For 70 × 70 × 70 mm octet-truss lattice structure, the FEA computation file size reached 36.6 GB. The CAD file size of a 200 x 200 x 200 mm octet-truss lattice structure reached nearly 290 MB. In conclusion, this study exposes the performance inadequacy of current CAD and CAE tools and CAD file formats to design lattice structures for additive manufacturing parts.

Methodology for Protection Performance Evaluation on Power Transmission Networks

An innovative methodology for protection performance evaluation on transmission networks is presented in this paper. It was developed to overcome difficulties faced by the Brazilian utility Companhia Hidro Eletrica do Sao Francisco (CHESF) during the preparation of short-circuit reports that must be sent to regulatory organizations whenever transmission-line faults occur. In the proposed methodology, a combination of several algorithms is used to extract from oscillographic records relevant information about short circuits and performance of protection functions. Aiming toward practical applications in CHESF, a software named disturbance analysis and protection performance evaluation has been developed in order to execute the proposed methodology functions, providing reports about the short-circuit characteristics and protection operation. To validate the proposed methodology, digital fault simulations in the Alternative Transients Program (ATP) and in Computer-Aided Protection Engineering (CAPE) software were carried out. Furthermore, real-world fault cases were also analyzed by assessing actual oscillographic fault records provided by CHESF. The obtained results show that the proposed methodology is reliable and quite useful for short-circuit analysis and protection performance evaluation procedures.

Beyond the Sticking Point

This article discusses that new friction theories can help engineers not only avoid costly blunders but also come up with elegant novel solutions to longstanding challenges. The article also highlights that conventional design tools such as the computer-aided design or computer-aided engineering software, deal with friction by assuming a constant value of the coefficient of friction. Engineers would be better off defining that parameter themselves to capture the dynamic nature of friction. Frictional effects are increasingly important with miniaturization. This is because small devices have high surface-to-volume ratios, with surface forces such as friction and adhesion dominating over the volume forces. Relying on the old-fashioned models of friction provides insufficient precision for micron- or submicron-size devices. The examples described in the article suggest that proper incorporation of dynamic friction into engineering design models and software can be beneficial for practical engineers.

Rotation of intramedullary alignment rods affects distal femoral cutting plane in total knee arthroplasty.

Intramedullary rods are widely used to align the distal femoral cut in total knee arthroplasty. We hypothesised that both coronal (varus/valgus) and sagittal (extension/flexion) cutting plane are affected by rotational changes of intramedullary femoral alignment guides. Distal femoral cuts using intramedullary alignment rods were simulated by means of a computer-aided engineering software in 4°, 6°, 8°, 10°, and 12° of valgus in relation to the femoral anatomical axis and 4° extension, neutral, as well as 4°, 8°, and 12° of flexion in relation to the femoral mechanical axis. This reflects the different angles between anatomical and mechanical axis in coronal and sagittal planes. To assess the influence of rotation of the alignment guide on the effective distal femoral cutting plane, all combinations were simulated with the rod gradually aligned from 40° of external to 40° of internal rotation. Rotational changes of the distal femoral alignment guides affect both the coronal and sagittal cutting planes. When alignment rods are intruded neutrally with regards to sagittal alignment, external rotation causes flexion, while internal rotation causes extension of the sagittal cutting plane. Simultaneously the coronal effect (valgus) decreases resulting in an increased varus of the cutting plane. However, when alignment rods are intruded in extension or flexion partly contradictory effects are observed. Generally the effect increases with the degree of valgus preset, rotation and flexion. As incorrect rotation of intramedullary alignment guides for distal femoral cuts causes significant cutting errors, exact rotational alignment is crucial. Coronal cutting errors in the distal femoral plane might result in overall leg malalignment, asymmetric extension gaps and subsequent sagittal cutting errors.

A VR simulation framework integrated with multisource CAE analysis data for mechanical equipment working process

Nowadays, the virtual reality (VR) technology has been widely used in machinery to verify the working process and performance of equipment prototype in early design stage. To gain insight into the coupling of process verifying the timing and rhythm of equipment working and performance indicating the quality of equipment, a VR framework is proposed in this paper to integrate the modeling and simulation of working process with the visualization of multisource analysis data from various computer-aided engineering (CAE) software. The framework is equipped with an extended discrete event system specification (DEVS) method, named scripted DEVS, which divides the process modeling into two stages, namely, behavior modeling and data customization, and frees the mechanical designer from programming. Based on the method, a uniform procedure of data integration is designed to hide the specific structure and visualization implementation of diverse data from the modeler by a script format called PDTree (Process&Data Tree) and a series of visualization interfaces in model-view-controller (MVC) pattern. Three applications of different working processes are also presented finally to verify the flexibility and compatibility of the framework.

XRTSDIC: model transformation from PIM to PSM

Computer Aided Software Engineering (CASE) has been growing faster in software industry. As part of it Model Driven Engineering (MDE) has been around for focusing on models and transforming them from one model to other model. The tool named Extensible Real Time Software Design Inconsistency Checker (XRTSDIC) proposed by us in previous paper supports UML modelling, design inconsistency checking and model transformation from UML to ERD to SQL. In this paper it is extended further to facilitate model transformation from PIM (UML class diagram) to PSM (source code). We proposed an algorithm and defined model transformation and consistency rules. The extended framework has provision for class relationship analysis and support for choosing different object oriented languages like C#, C++ and Java. While transforming the model, we used the concept of dialects. Dialect is the class with transformation functionality which has ability to adapt to syntax and semantics of chosen language. Different dialects are made available for different languages. Thus the proposed system is capable of transforming models and the prototype application we built and extended demonstrates the proof of concept. The empirical results revealed that the model transformation is consistent and accurate.

OVERVIEW OF THE TALISMAN VERSION 5 SOFTWARE ENGINEERING META-ENVIRONMENT

This report presents an overview of Talisman's version 5 functionality. Talisman is a computer aided software engineering meta-environment. It focuses strongly on model driven tools. It provides means to build software development and maintenance environments composed of a harmonious collection of representation languages and tools. The set of representation languages and tools may cover a very wide variety of development and maintenance activities. Talisman operates on a net of workstations, each containing an environment instance providing tools to support some of the activities of a specific software development and maintenance process. The collection of environment instances supports a large portion of the activities of a given development process. Talisman stores fine grained objects in a distributed repository. The base schema and meta-schema of this repository as well as the definition of user interfaces, representation languages and tools are kept in a definition base. Definition bases are derived from an environment base which contains all facts about supported representation languages and tools. The environment base is used by the environment builder to create and maintain representation languages and to adapt tools to the specific needs of a particular project. One of the basic aims of Talisman is to compose and maintain code and other artifacts from high level specifications relying heavily on model driven activities. The result of the development using Talisman is a hyper-document interrelating all artifacts that constitute the target system. The construction and maintenance of this hyper-document is achieved by successive transformations, modifications and verifications of a variety of models. To define and fine-tune these tools, Talisman uses an internal programming language, which specializes tools and activities, such as editors, code composers, representation transformers, representation verifiers and hyper-document navigation control.

Surface fairness: a quality metric for aesthetic assessment of compliant automotive bodies

ABSTRACTThe superior quality of automotive body surfaces is nowadays of growing concern to any customer. Thus, it has been one of the key issues in the car body designing process. The manufacturing tolerances play a crucial role in the quality of products in mass production. With the advances in computer-aided design and engineering (CAD/CAE) software, the tolerance analysis has been taken into detailed consideration for aesthetic assessment of automotive bodies in recent decades. In this paper, the surface fairness has been chosen as a quality metric for the compliant automotive bodies. The relationship between input statistical tolerances and output fairness factor of the assembly has been established by integrating finite element analysis (FEA) with surface interrogation techniques in order to visually assess the quality of products prior to costly manufacturing processes. The proposed methodology is categorised into three main modules: nonlinear FEA, fairness assessment, and statistical analysis. The results of this study, validated by experimental measurements, clearly demonstrate that input tolerances exert powerful effects on the quality of surfaces and, hence, the aesthetic characteristics of the final assembled products.

EKSPANPIXEL BLADSY STRANICA: Performance Efficiency Improvement of Making Front-End Website Using Computer Aided Software Engineering Tool

The purpose of this research is to create a front-end website engine to improve the efficiency of front-end website creation called Expanpixel Bladsy Stranica (EBS). The method of making front-end website engine adopts computer aided software engineering (CASE) tool model, then to make it easier to access anywhere, it is made online (website-based), and evaluated by way of manual creation of front-end website and using EBS. After that the data obtained were analyzed using statistical formula. Results of increasing efficiency of front-end website creation performance that occurred on average by 83.60% of the overall developer.

Polymer based microneedle patch fabricated using microinjection moulding

This paper presents the development of a polymer based microneedle patch for transdermal drug delivery application using plastic microinjection moulding. Design and analysis of the microneedle cavities and mould insert used in the injection moulding process were carried out using Computer-Aided Engineering (CAE) software. A mould insert with low surface roughness was fabricated using Micro Electrical Discharge Machining (μ-EDM). The injection moulding parameters including clamping force, temperature, injection pressure and velocity were characterized in order to obtain the optimum reproducibility. Solid truncated cone microneedles, made of biocompatible polymethyl methacrylate (PMMA), with a round tip radius of 50 μm and 500 μm in height have been realized by microinjection moulding process demonstrating the potential of a low cost, high production efficiency, and suitable for mass production. In addition, a mould insert of cylindrical microneedles fabricated using X-ray LIGA has been proposed.

Corporate environmental information system data storage development and management (Environmental Information System)

Abstract In this article a software implementation of the environmental monitoring is developed and presented, which is responsible for receive, store, process and analysis of data. For logical database design system Computer- Aided Software Engineering (CASE) technology, the AllFusion ERwin Data Modeler was selected. To develop corporate Oracle database management system used. The database contains a set of objects, which store all the primary and additional service information, as well as a set of software modules of business logic. The developed information system makes it possible to find optimal solutions for clean and disposal of the contaminated areas. There are advantages of created databases on the areas to be remediated, such as the analysis of remediation made by using plants.

Study of the design of cooling channels for polymers injection molds

The development of additive manufacturing using metallic materials, such as the selective laser melting, has allowed the manufacture of free form cooling channels inside the molds for plastic injection. Reduction on the injection cycle time and product quality are expected using such cooling channels (also known as conformal cooling channels). The knowledge to design such cooling system are limited today. This work aims to collaborate with this issue. A new design of cooling channels using series and parallel concept are proposed and its efficiency were analyzed against some conformal cooling geometry found on the literature today. The analyses were carried out by a Computer Aided Engineering software using an automotive component as a workpiece. The results show that the design of the new approach of conformal cooling channels has an influence on the cooling performance and if the conformal cooling was not carefully designed, it cannot achieve the expected benefits. POLYM. ENG. SCI., 58:552–559, 2018. © 2017 Society of Plastics Engineers

Dynamic modeling and optimization of an ORC unit equipped with plate heat exchangers and turbomachines

Nowadays environmental concerns call for a transition towards an economy based on fossil fuels to a low carbon one. In order to achieve this goal, efficiency optimization of existing energy systems through waste heat to power conversion units based on bottoming Organic Rankine Cycles (ORC) is one of the actions that appears to be suitable and effective both from cost and environmental perspectives. Indeed, these units are able to increase the overall efficiency of production processes, existing facilities and renewable power plants with a limited payback time. However, despite the increasing number of ORC installations at megawatt scale, the waste heat rejected by industrial processes has rather a widespread nature. Hence, ORC units with a power output in the range of kilowatts should be developed to address this opportunity for heat recovery and for business.In the current research activity, a dynamic model of an ORC system was developed in a commercial 1D Computer Aided Engineering software platform. Sub-models of the two plate heat exchangers and of the multi-stage centrifugal pump were developed and calibrated using performance data of industrial components at design and off-design conditions. On the other hand, the R245fa radial turbine design was accomplished using a design procedure that provided geometrical and performance data for the mapping of the device by means of a 1D tool. A steady-state off-design analysis at different operating conditions at the evaporator was further carried out optimizing pump and turbine speeds to maximize the net power output. Furthermore, the thermal inertial effects at the evaporator were assessed with reference to a sample heat load profile of the water hot source and at different time scales.

Designing an Orthotic Insole by Using Kinect® XBOX Gaming Sensor Scanner and Computer Aided Engineering Software

Healthcare and medical is one of the most expensive field in the modern world. In order to fulfil medical requirement, this study aimed to design an orthotic insole by using Kinect Xbox Gaming Sensor Scanner and CAE softwares. The accuracy of the Kinect® XBOX 360 gaming sensor is capable of producing 3D reconstructed geometry with the maximum and minimum error of 3.78% (2.78mm) and 1.74% (0.46mm) respectively. The orthotic insole design process had been done by using Autodesk Meshmixer 2.6 and Solidworks 2014 software. Functionality of the orthotic insole designed was capable of reducing foot pressure especially in the metatarsal area. Overall, the proposed method was proved to be highly potential in the design of the insole where it promises low cost, less time consuming, and efficiency in regards that the Kinect® XBOX 360 device promised low price compared to other digital 3D scanner since the software needed to run the device can be downloaded for free.

تصميم وتحليل نظام خبير لقياس جودة البرمجيات باستخدام EAOMT

في هذا البحث ، تم تصميم أداة هندسة البرمجيات بمساعدة الكمبيوتر (أداة الحالة) والتي تسمى (التحليل الخبير لأداة المقاييس EAFMT) والتي تُستخدم في نشاط التصميم ، وتنفذ هذه الأداة إحدى تقنيات الذكاء الاصطناعي الشهيرة وهي الأنظمة الخبيرة ، تقييم وتحسين جودة النظام تلقائيًا. تقيس هذه الأداة جودة البرمجيات في نشاط التصميم ، ويعتمد عملها على تحليل الرسوم البيانية للفئة (الرسم التخطيطي للفئة هو أحد مخططات لغة النمذجة الموحدة (UML)) ، والذي يتم عن طريق إنشاء محلل يستخرج المعلومات الضرورية للعثور على مقاييس التصميم ، ثم يتم تقييم كل مقياس بمفرده داخل نظام الخبراء. تهدف هذه الأداة إلى تقليل الموارد المستخدمة والوقت الضخم الذي يقضيه في فحص البرامج المتعلقة بالتصميم ، وتضمن أيضًا جودة عالية للنظام المُنتَج كما توقع العميل والمستخدم. تم اختبار أداء هذه الأداة من خلال تطبيق الرسم التخطيطي لآلة الصراف الآلي للأجهزة المحمولة (الذي تم إنشاؤه باستخدام البرمجة الموجهة للكائنات) عليها ، ونجحت في تحليل وتقييم جودة المخطط بناءً على الأنظمة الخبيرة.