Development of compact circular polarized antenna for WLAN application

Matching the polarization in both the transmitter and receiver antennas is important in terms of decreasing transmission losses. The use of circularly polarized antennas presents an attractive solution to achieve this polarization match which allows for more flexibility in the angle between transmitting and receiving antennas, reduces the effect of multipath reflections, enhances weather penetration and allows for the mobility of both the transmitter and the receiver. Compact circularly polarized microstrip antenna with Circular Polarization (CP) property for wireless communication system at 2.45 GHz is presented. Microstrip patch antennas being popular because of light weight, low volume, thin profile configuration which can be made conformal. Wireless communication systems applications circular polarization antenna is placing vital role. In this study it was applied DGS to produce circular polarization. The single fed circular polarized microstrip antenna is etched on a FR4 with dielectric substrate of 4.3 with the height of 1.6 mm. The axial ratio of approximate 2.1 dB and the radiation pattern results prove that the designed antenna meets the CP criteria. The simulated and measured results show a good agreement and the proposed antenna is suitable for WLAN applications

Конвертация топологических данных с использованием параллельных вычислений

В статье рассмотрены алгоритмы конвертации топологических данных из форматов САПР в формат Т29 (формат установок автоматического контроля топологических структур на фотошаблонах производства УП «КБТЭМ-ОМО»), который напрямую не поддерживается современными САПР. Особенность таких данных – большой объем данных и, следовательно, время конвертации. Использование параллельных методов вычислений на базе ПЭВМ с многоядерным процессором и технологии OpenMP позволяет значительно ускорить время обработки данных.У статті розглянуті алгоритми конвертації топологічних даних з форматів САПР у формат Т29 (формат установок автоматичного контролю топологічних структур на фотошаблонах виробництва УП «КБТЕМ-ОМО»), який прямо не підтримується сучасними САПР. Особливість таких даних – великий обсяг даних і, відповідно, час конвертації. Використання паралельних методів обчислень на базі ПЕОМ з багатоядерним процесором і технології OpenMP дозволяє значно прискорити час обробки даних.In this paper, we propose algorithms and software for parallel implementation of conversion of VLSI Layout Data from CAD format Gerber and MEBES into an internal representation and then into format of automatic mask inspection system T29. The software is developed on basis of OpenMP technology to work on PC with 4-core processor. It is shown that using parallel computing speeds up a conversion process. In the future we are planning to develop similar tools for data conversion from CIF and DFX formats into the internal format, and further into format GDS-II. These tools allow developing a program complex of topological data processing to work with automatic mask inspection system made by R&D Company “KBTEM-OMO” of “Planar” Corporation

Past, present and future of information and knowledge sharing in the construction industry: Towards semantic service-based e-construction

The paper reviews product data technology initiatives in the construction sector and provides a synthesis of related ICT industry needs. A comparison between (a) the data centric characteristics of Product Data Technology (PDT) and (b) ontology with a focus on semantics, is given, highlighting the pros and cons of each approach. The paper advocates the migration from data-centric application integration to ontology-based business process support, and proposes inter-enterprise collaboration architectures and frameworks based on semantic services, underpinned by ontology-based knowledge structures. The paper discusses the main reasons behind the low industry take up of product data technology, and proposes a preliminary roadmap for the wide industry diffusion of the proposed approach. In this respect, the paper stresses the value of adopting alliance-based modes of operation

Development of the PC-based Integrated Interface System of STEP file for CNC Machining Application: Circular Features

STEP is a general data format that observes the international standard ISO 10303-21. STEP means Standard for the Exchange of Product model data. It consists of the 3D geometry of a computer-aided design (CAD) model in the configuration of boundary representation (B-rep). By extracting, refining and decoding the geometric data correctly, the data can be utilized for writing G-code for Computer Numerical Control (CNC) machining application.  Usually G-codes can either be manually generated by skilled machinists or automatically generated by computer-aided manufacturing (CAM) software. However, manually generated G-code is inefficient and susceptible to error. Meanwhile automated generation G-code requires significant setup cost. This paper describes the design and development of an integrated interface system, an instrument aimed to be used to analyze STEP files and generate machining tool path based on ISO 6983 format. This developed interface reduces the need for high setup cost as well as eliminates human limitations. The interface at present is able of detecting circular machining features on the workpiece. Circular machining features are created by 3D modelling software and retained as STEP file. The STEP file which contains geometrical data is then uploaded to the interface system as an input file which is structurally analyzed and processed.  Finally, the ideal machining tool path in the G Code format is proposed and generated. By bypassing the CAM software and its proprietary post processor, the outcome of this research is important to enhance compatibility between different CNC machine system

B-code Generation for a CNC Dentistry Wire Bending Mechanism

In the present study, the generation of CNC wire bending code (B-code) is explored and an automatic converter is developed in Excel through some mathematical formulae. The B-code comprises of three parameters which have been determined from the previous work, known as feeding length (L), plane rotation angle (R) and bend-ing angle (A). These parameters control the movement of the designed wire bending machine in this way; (L) tells the feeding mechanism how long the straight wire to be fed, (R) constructs the turning mechanism to rotate in certain degrees before the bending operation starts and (A) determines the degrees of bend, performed by the bending mechanism. The input of the converter is the Cartesian XYZ coordinate of each bend point, obtained from the CAD file. This paper also describes the XYZ extraction process from an IGES file, in addition to the CNC code generation. The practicality of these procedures is demonstrated through an example, starting from the wire design, follows by the XYZ extraction and ends with the B-code generation. Moreover, the graphical simulation of the bending operation by the designed mechanism is also presented. However, the capability of these codes in controlling the wire bending machine in the real bending operation will not be discussed in the present work

Analyzing and Implementing a Feature Mapping Approach to CAD System Interoperability

Interoperable information exchange between computer-aided design (CAD) systems is one of the major problems to enable information integration in a collaborative engineering environment. Although a significant amount of work has been done on the extension and standardization of CAD data formats as well as the cooperation of CAD systems in both academy and industry, these approaches are generally low-level and narrowly targeted. Lack of fundamental study of interoperability and generic solution to this problem is the major issue. Our intention of this research is to design a solution of CAD feature interoperability as generic as possible based on a theoretical foundation of language types. In this paper, we present a fundamental model of semantic features and feature mapping process based on the type theory. We implement and demonstrate our approach for automated feature exchange between commercial CAD systems

A survey on 3D CAD model quality assurance and testing

[EN] A new taxonomy of issues related to CAD model quality is presented, which distinguishes between explicit and procedural models. For each type of model, morphologic, syntactic, and semantic errors are characterized. The taxonomy was validated successfully when used to classify quality testing tools, which are aimed at detecting and repairing data errors that may affect the simplification, interoperability, and reusability of CAD models. The study shows that low semantic level errors that hamper simplification are reasonably covered in explicit representations, although many CAD quality testers are still unaffordable for Small and Medium Enterprises, both in terms of cost and training time. Interoperability has been reasonably solved by standards like STEP AP 203 and AP214, but model reusability is not feasible in explicit representations. Procedural representations are promising, as interactive modeling editors automatically prevent most morphologic errors derived from unsuitable modeling strategies. Interoperability problems between procedural representations are expected to decrease dramatically with STEP AP242. Higher semantic aspects of quality such as assurance of design intent, however, are hardly supported by current CAD quality testers. (C) 2016 Elsevier Ltd. All rights reserved.This work was supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund, through the ANNOTA project (Ref. TIN2013-46036-C3-1-R).González-Lluch, C.; Company, P.; Contero, M.; Camba, J.; Plumed, R. (2017). A survey on 3D CAD model quality assurance and testing. Computer-Aided Design. 83:64-79. https://doi.org/10.1016/j.cad.2016.10.003S64798

Моделі та інформаційні технології проектування і управління в складних системах

Мета роботи: розробка теоретико-методологічних і науково-практичних основ розробки інформаційних технологій управління та інформаційних систем на потреб галузей суспільного виробництва та соціальної сфери

A framework of contextual knowledge in three dimensional computer aided design for mechanical engineering undergraduates

Today’s industries demand engineering graduates who are equipped with good knowledge and skills in using modern Three Dimensional Computer Aided Design (3D CAD). However, the recent research findings show that there is a lack of contextual knowledge among Mechanical Engineering Undergraduates when utilizing 3D CAD modeling software to develop a good product design. Most of them are not able to contextualize their created model in the aspects of manufacturing and user applications. This study was conducted to explore the essential contextual knowledge elements in the process of developing 3D CAD models among practitioners in manufacturing industries. The constructs of digital product modeling were established for this study, known as the contexts of Model Creation, Model Manipulation, Model Visualization and Model Transfer. A transcendental phenomenology approach was used as the main research design of this study. The participants of this study were practicing engineers from a shipbuilding company in Peninsular Malaysia. They have been purposefully selected to explore their experiences in utilizing the elements of contextual knowledge in 3D CAD modeling applications in their daily design works. All collected data were analyzed using phenomenological analysis. The textural and structural descriptions were gathered to capture what and how the essential contextual knowledge elements from each practicing engineer in the application of 3D CAD modeling within four digital product modeling contexts. Relevant documents were analyzed from practicing engineers to triangulate the main data for this study. The study has successfully developed a framework of Contextual Knowledge in 3D CAD modeling, which consists of three main elements: Realization, Design Intention and Normalization. By injecting these three elements in teaching and learning 3D CAD modeling, students can be expected to develop a creative and innovative product design and may lead to better usability of 3D CAD software in the product modeling process