Interoperability of Design Intent in Integrated Product and Process Design

Concurrent engineering is currently an overwhelming t rend in product development since it takes the down-stream product development issues and product life-cycle issues into consideration in up-front design pro cess. At this stage, evaluation, verification and validation of design concepts and design schemes is critical to the right-to-market product development. I dentification and extraction of design intent from the part digital mock-ups in different data formats and created in different CAD systems for DFX considerati on, evaluation, verification, and validation is crucial too. Traditionally, fro m manufacturing point of view, feature identification and extraction is to get t he features and feature-related information for manufacturing planning and inte gration. Presently, from the viewpoint of product development and product servi ce life cycle, design intent identification and extraction is to get all the des ign-related information for DFX consideration in early design stage, such as de sign for assembly, design for service, design for tooling, design for functional ity and design for environment etc. Therefore, how to successfully extract desi gn intent such as design and machining features and design-related information from the prototyping digital mock-ups created by different CAD systems for DFX consideration in upstream design stage is a very useful topic in integrated prod uct and process design and development. Presently, there are heterogeneous CAD systems in the market and the interoperat ion among the different CAD systems is indispensable. The interoperability of d ifferent CAD systems is by way of data exchanged technology such as STEP and IGE S. The critical weakness of this interoperation technology is that much of the design intent is lost in the interoperation process. Once the product digital m ock-ups is exchanged via data exchange technology such as IGES or STEP, the des ign intent including the dimension-driven design features and other attributes embedded in the part model are lost in the data translation process. Models rea d out of CAD systems come into other systems as featureless chunks of geometry e ntities. Obviously, the interoperation technology does not satisfy the industry need. It has been reported that this poor interoperation technology, which pro vides poor CAD models in neutral-format geometry had cost the automobile indust ry alone $1 billon per year. Fortunately, some researchers have been aware of t he criticality of this since only the United States industry spends billons of d ollars as a result of poor interoperability between computer-aided engineering software tools. In the past, product development was often done within a single company by co-located design team. In more recent years, there has been a busi ness paradigm shift in product development as the product development is being d one more often by geographically and temporally distributed design teams. There is a high level of outsourcing, not only of manufacturing but also of actual pr oduct development effort. Besides, product development across companies, and ev en within a single company, is often done within a heterogeneous software tool e nvironment. How to improve the interoperability of design intent created in het erogeneous software tool environment geographically has become a critical issue in next-generation product development system. Design intent in this research is defined as the outcome of design process. Des ign process goes from the identification of needs to satisfaction of that needs. Design intent satisfies this kind of needs. In this research, design intent i s created in a CAD system and embedded in part CAD model. The detailed design i ntent here includes design and manufacturing features and the feature-relat ed information such as feature parameters, feature relationships and some relate d characteristics such as associativity. Interoperability refers to the ability to share and communicate in the heterogeneous environment or heterogeneous soft

Significance of ROI Coding using MAXSHIFT Scaling applied on MRI Images in Teleradiology-Telemedicine

Within the expanding paradigm of medical imaging in Teleradiology-Telemedicine there is increasing demand for transmitting diagnostic medical imagery. These are usually rich in radiological contents and the associated file sizes are large which must be compressed with minimal file size to minimize transmission time and robustly coded to withstand required network medium. It has been reinforced through extensive research that the diagnostically important regions of medical images, the Region of Interest (ROI), must be compressed by lossless or near lossless algorithm while on the other hand, the background region be compressed with some loss of information but still recognizable using JPEG 2000 standard. We develop a compression model and present its application on MRI images. Applying on MRI images achieved higher compression ratio 16:1, analogously minimum transmission time, using MAXSHIFT method proved diagnostically significant and effective both objectively and subjectively.

Non-rigid registration and KLT filter to improve SNR and CNR in GRE-EPI myocardial perfusion imaging

The purpose of the study was to evaluate the effect of motion compensation by non-rigid registration combined with the Karhunen-Loeve Transform (KLT) filter on the signal to noise (SNR) and contrast-to-noise ratio (CNR) of hybrid gradient-echo echoplanar (GRE-EPI) first-pass myocardial perfusion imaging. Twenty one consecutive first-pass adenosine stress perfusion MR data sets interpreted positive for ischemia or infarction were processed by non-rigid Registration followed by KLT filtering. SNR and CNR were measured in abnormal and normal myocardium in unfiltered and KLT filtered images following nonrigid registration to compensate for respiratory and other motions. Image artifacts introduced by filtering in registered and nonregistered images were evaluated by two observers. There was a statistically sig- nificant increase in both SNR and CNR between normal and abnormal myocardium with KLT filtering (mean SNR increased by 62.18% ± 21.05% and mean CNR increased by 58.84% ± 18.06%;p = 0.01). Motion correction prior to KLT filtering reduced significantly the occurrence of filter induced artifacts (KLT only-artifacts in 42 out of 55 image series vs. registered plus KLT-artifacts in 3 out of 55 image series). In conclusion the combination of non-rigid registration and KLT filtering was shown to increase the SNR and CNR of GRE-EPI perfusion images. Subjective evaluation of image artifacts revealed that prior motion compensation significantly reduced the artifacts introduced by the KLT filtering process.