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Robotized blasting of ship hull surfaces requires an accurate identification of defective regions of the hull to maximize the blasting efficiency. Accurate surface defect detection may not be achieved by current manual procedures, as its success is highly vulnerable to the human operators' experience and their subjective judgements. Therefore, there is a need for a more accurate and non-subjective method for defect detection. This paper proposes a computer vision based method for detection of ship hull defects. The method utilizes the histogram of hue and entropy data of the hue to identify the defects in two steps. Step 1 is an automatic circular thresholding based on the histogram of hue to distinguish the defects whose hue is different from the defect-free regions. A wrapped Gaussian mixture model is utilized to estimate the circular hue histograms, and maximum likelihood criterion is adopted to set the thresholds. Step 2 uses the probability distribution of the entropy for each segment identified in the first step to decide whether the segments are either defective, defect-free or a mixture of both. For the mixed regions, a Gaussian mixture model is fitted to the probability distribution of the entropy. The maximum likelihood criterion is utilized to segment these regions so as to discriminate their defective and defect-free parts. The high accuracy (F-measure=0.89) and short execution time ( ~ 3.5 s) of the proposed method show that it is a good starting point for an automatic defect detection for a fully autonomous ship hull blasting.

This paper presents information on some of the characteristics of demand for eggs in Canada using cross section and time series approaches. Data from the 1969 Expenditure Survey are analyzed by cross-section to establish responsiveness of egg consumption to income, family structure, and an implicit price index used to designate different quality levels purchased. Monthly producer prices are used to establish estimates of price flexibility, seasonal, U.S. price, breaker market and inventory effects, and a computed index is used to indicate the effect of changes in quality distribution on price. In addition, a model is formulated from the reinforcement theory of habit formation to lest for the existence of inertia! or habitual behavior in egg purchases. The relevance of the results to market regulation is illustrated as well as their application in price forecasting. Cette etude donne des informations sur quelques-uns des characteristiques de la demande des oeufs au Canada, ce en utilisant des series chronalogiques el des coupes transversales (cross-section). Les donnees provenam de ľEtude de la Consommation datum de 1969 soul analysers par coupes transversales (cross-section) afin de determiner ľeffet sur la consommation des oeufs des revenus, des structures familiales ainsi que ľindice des prix implicite servant a designer ľacquisition des differents niveaux de qualite. Les prix mensuels au producteur sont utilises afin ďestimer la flexibilite des prix, saisonniers, les prix aux Etats-Unis. les effets du Marche rentable (breaker market) et resultats invemtaires, el un inclice calcule est utilise pour demontrer ľeffet des changements de la distribution des differentes qualites sur les prix. De plus, un modele est construit a partir de la theorie de renforcemenl des habitules ďachat afin de verifier ľexistence ďun comportement inertial ou habitue! des acheleurs ďoeufs. La pertinence des resultats sur les reglements du Marche est illustre ainsi que leurs applications dans la prevision des prix.

Design is an integral component of product development, which includes manufacturing. In order to avoid costly reworks and delays, and to reduce the lead-time in product development, effective communication of design concepts among the various stakeholders such as customers, designers and engineers is of utmost importance. In this respect, functional representations provide a methodology, which can be used to describe a design or product effectively. However, function is not the only type of information that needs to be communicated among the various stakeholders during a design process. Other types of information such as design specifications and constraints, which are non-functional, also need to be taken into account. This non-functional information cannot be adequately expressed using existing functional representations. Accordingly, in this work, a novel purpose-behaviour-structure (PBS) representation scheme to capture vital design knowledge for collaborative product development is proposed. The proposed PBS representation scheme can be used by designers working in a collaborative environment for product development. A case study on the design of a vacuum cleaner is used to illustrate the functionality of the PBS representation scheme. The details of the representation scheme are presented in this paper.

Methane (CH4) emissions from rice fields were monitored in Hangzhou, China, from 1995 to 1998 by an automatic measurement system based on the "closed chamber technique." The impacts of water management, organic inputs, and cultivars on CH4 emission were evaluated. Under the local crop management system, seasonal emissions ranging from 53 to 557 kg CH4 ha−1 were observed with an average value of 182 kg CH4 ha−1. Methane emission patterns differed among rice seasons and were generally governed by temperature changes. Emissions showed an increasing trend in early rice and a decreasing trend in late rice. In a single rice field, CH4 emissions increased during the first half of the growing period and decreased during the second half. Drainage was a major modifier of seasonal CH4 emission pattern. The local practice of midseason drainage reduced CH4 emissions by 44% as compared with continuous flooding; CH4 emissions could further be reduced by intermittent irrigation, yielding a 30% reduction as compared with midseason drainage. The incorporation of organic amendments promoted CH4 emission, but the amount of emission varied with the type of organic material and application method. Methane emission from fields where biogas residue was applied was 10–16% lower than those given the same quantity (based on N content) of pig manure. Rice straw applied before the winter fallow period reduced CH4 emission by 11% as compared with that obtained from fields to which the same amount of rice straw was applied during field preparation. Broadcasting of straw instead of incorporation into the soil showed less emission (by 12%). Cultivar selection influenced CH4 emission, but the differences were smaller than those among organic treatments and water regimes. Modifications in water regime and organic inputs were identified as promising mitigation options in southeast China.

One of the challenging problems that hinder the development of Cloud-based collaborative systems is the contradiction of large design or manufacturing visualization data and the limited bandwidth of the Internet and Web to share the data remotely to support collaborative work. Faster visualization of design and manufacturing models during collaboration has been needed for a long time. Recently, a new scheme for visualization has been presented, viz., the 3D streaming technology. 3D streaming technique can allow effective dispatch and access of large-volume design and manufacturing data as a series of patched streams across the Internet, and therefore provide a promising solution to overcome the obstacle. The key technology to realize the streaming technique is geometric simplification (or decimation) of 3D models. In this chapter, a new streaming technology based on a geometric simplification algorithm has been developed, in which two criteria are the crucial elements to control the collapse process for edges in 3D visualization models represented in VRML. After the simplification and sharing of a model, a developed refinement algorithm is carried out to restore the model from its simplified version back to its original, through combining the simplified model with some reconstruction data generated during the simplification process, therefore, to realize the streaming information sharing. The major feature of the streaming algorithm is that it has incorporated some advantages of the previously developed vertex decimation approach and edge collapse approach. Meanwhile, the mechanism of adaptive threshold parameters adopted in this work enhances the adaptability of the algorithm for various applications. Case studies and comparisons with some related works have been carried out to demonstrate the performance and potentials of the algorithm in terms of efficiency, adaptability and robustness.

This paper investigates two sampling strategies, dense sampling and PHOW sampling, for bag-of-features 3D CAD model retrieval. Previous methods [1] use original salient SIFT feature detection for general 3D model retrieval which does not suit the need for CAD models representation. CAD models contain mostly piecewise-smooth surfaces and thus only sharp edges can be described. To overcome these limitations, two new sampling strategies are investigated to improve the feature extraction process. Dense sampling extracts SIFT features on regular spatial grids with even spacing. Pyramid Histogram Of visual Words (PHOW) [2] extracts features on repeatedly finer scales. Both the two sampling methods extract features that are covered the whole shape. In addition, the influences of codebook size and distance metric are also studied to optimize the retrieval performance. Experiments on Purdue Engineering Benchmark [3] show that the proposed sampling techniques achieve better retrieval accuracy than the original salient SIFT sampling method.Copyright © 2011 by ASME

In this paper, the construction of a detailed spine model is presented using the LifeMOD Biomechanics Modeler. The detailed spine model is obtained by refining spine segments in cervical, thoracic and lumbar regions into individual vertebra segments, using bushing elements representing the intervertebral discs, and building various ligamentous soft tissues between vertebrae. In the sagittal plane of the spine, constant force will be applied from the posterior to anterior during simulation to determine dynamic characteristics of the spine. The force magnitude is gradually increased in subsequent simulations. Based on these recorded dynamic properties, graphs of displacement-force relationships will be established in terms of polynomial functions by using the least-squares method and imported into a haptic integrated graphic environment. A thoracolumbar spine model with complex geometry of vertebrae, which is digitized from a resin spine prototype, will be utilized in this environment. By using the haptic technique, surgeons can touch as well as apply forces to the spine model through haptic devices to observe the locomotion of the spine which is computed from the displacement-force relationship graphs. This current study provides a preliminary picture of our ongoing work towards building and simulating bio-fidelity scoliotic spine models in a haptic integrated graphic environment whose dynamic properties are obtained from LifeMOD. These models can be helpful for surgeons to examine kinematic behaviors of scoliotic spines and to propose possible surgical plans before spine correction operations., {"references":["M. A. Adams, and P. Dolan, \"Recent advances in lumbar spinal\nmechanics and their clinical significance,\" Clin. Biomech., vol. 10, no.\n1, pp. 3-19, Jan. 1995.","J. P. Callaghan, and S. M. McGill, \"Low back joint loading and\nkinematics during standing and unsupported sitting,\" Ergonomics, vol.\n44, no. 3, pp. 280-294, Feb. 2001.","B. Vallfors, \"Acute, subacute and chronic low back pain: clinical\nsymptoms, absenteeism and working environment,\" Scand. J. Rehab.\nMed. Suppl., vol. 11, pp. 1-98, 1985.","K. Luoma, H. Riihimaki, R. Luukkonen, R. Raininko, E. Viikari-\nJuntura, and A. Lamminen, \"Low back pain in relation to lumbar disc\ndegeneration,\" Spine, vol. 25, pp. 487-492, 2000.","K. W. Lee, \"CAD system for human-centered design,\" Computer-Aided\nDesign & Applications, vol. 3, no. 5, pp. 615-628, 2006.","H. S. Ahn, \"A virtual model of the human cervical spine for physicsbased\nsimulation and applications,\" Ph.D dissertation, University of\nTennessee, May 2005.","C. U. De Jongh, A. H. Basson, and C. Scheffer, \"Dynamic simulation of\ncervical spine following single-level cervical disc replacement,\" in\nProceedings of the 29th Annual International Conference of the IEEE\nEMBS, Lyon, France, 2007, pp. 4289-4292.","S. M. Kim, I. C. Yang, and M. P. Lee, \"Cervical spine injury analysis\nregarding frontal and side impacts of wheelchair occupant in vehicle by\nLifeMOD,\" in IFMBE Proceedings, 2007, vol. 14, no.4, pp. 2521-2524.","F. Cavalloa, G. Megalia, S. Sinigagliaa, O. Toneta, P. Darioa, and A.\nPietrabissa, \"A step towards biomechanical analysis of surgeon-s\ngesture on Adams-LifeMOD platform,\" Int. J. CARS, vol. 2, no. 1, pp.\n160-180, 2007.\n[10] SensAble.PHANTOMTM. Available: http://www.sensable.com\n[11] R. L. Williams, M. Srivastava, J. N. Howell, et al, \"The virtual haptic\nback for palpatory training,\" in Proceedings of the 6th International\nConference on Multimodal Interfaces, Pennsylvania, USA, 2004, pp.\n191-197.\n[12] P. Gorman, T. Krummel, R. Webster, M. Smith, and D. Hutchens, \"A\nprototype haptic lumbar puncture simulator,\" Stud. Health Technol.\nInform., vol. 70, pp. 106-109, 2000.\n[13] G. Boschetti, G. Rosati, and A. Rossi, \"A haptic system for robotic\nassisted spine surgery,\" IEEE Conference on Control Applications, pp.\n19-24, Aug. 2005.\n[14] Van C. Mow, and Wilson C. Hayes, Basic Orthopaedic Biomechanics.\nNew York: Raven Press Ltd., 1991, ch. 8.\n[15] M. H. Berkson, A. L. Nachemson, and A. B. Schultz, \"Mechanical\nproperties of human lumbar spine motion segments - Part 2: responses\nin compression and shear; influence of gross morphology,\" J. Biomech.\nEng., vol. 101, pp. 52-57, 1979.\n[16] K. M. McGlashen, J. A. Miller, A. B. Schultz and G. B. Andersson,\n\"Load displacement behavior of the human lumbo-sacral joint,\" J.\nOrthop. Res., vol. 5, pp. 488-496, 1987.\n[17] S. P. Moroney, A. B. Schultz, J. A. Miller, and G. B. Andersson, \"Loaddisplacement\nproperties of lower cervical spine motion segments,\" J.\nBiomech., vol. 21, pp. 769-779, 1988.\n[18] M. M. Panjabi, R. A. Brand, and Jr. White AA, III, \"Mechanical\nproperties of the human thoracic spine as shown by three-dimensional\nload-displacement curves,\" J. Bone Joint Surg. Am., vol. 58, pp. 642-\n652, 1976.\n[19] A. B. Schultz, D. N. Warwick, M. H. Berkson, and A. L. Nachemson,\n\"Mechanical properties of human lumbar spine motion segments. Part 1:\nResponses in flexion, extension, lateral bending and torsion,\" J.\nBiomech. Eng., vol. 101, pp. 46-52, 1979.\n[20] N. Yoganandran, N. Kumaresan, and F. A. Pintar, \"Biomechanics of the\ncervical spine. Part 2. Cervical spine soft tissue responses and\nbiomechanical modeling,\" Clin. Biomech., vol. 16, pp. 1-27, 2001."]}

Today’s global economy makes enterprise face ever-increasing challenges for short time-to-market, reduced time-to-volume, decreased time-to-profit. This requires companies closely work with each other for continuous innovation by leveraging intellectual property. Product Lifecycle Management (PLM) is recognized as one of leading technologies to facilitate enterprises to tackle these challenges. Following this trend, based on the complete analysis of business drivers, industry requirements, limit of current solution, and recent state-of-the-art review in the domain related to PLM, this study proposes the comprehensive future technology solutions for PLM. Potential industrial impact of the developed PLM technology is analyzed. It is hoped that the proposed PLM technology trend will form the frontier basis for further academic research and industrial application of PLM technology.Copyright © 2005 by ASME

In pursuit of the most competitive advantages in modern dynamic business environment, companies have recognized the importance of the real-time integrated collaboration of the different enterprise application systems. Manufacturing process planning plays a significant role by providing collaborative integration capabilities, from design to manufacturing. This situation is more acute in the tooling production industry, which is characterized by short lead-time and frequent dynamic customer requirements. A framework for concurrent design to manufacturing collaboration has been developed to support the integration of product design with manufacturing process planning. A prototype system based on this framework has been developed and tested in a tooling job shop with satisfactory results. Although the concurrent design to manufacturing collaboration framework has been developed for solving tooling production problems, it is generic and can be effectively applied in other production domains that require the support of collaborative integration.Copyright © 2005 by ASME

An integrated end-to-end lifecycle engineering process management system is deemed critical to boost the manageability, efficiency and responsiveness of an engineering enterprise. The challenge lies in the realization of such a system that is flexible and scalable. To overcome the challenge, a configurable module based system technology is developed to simplify the realization of a complex process management system and to offer the system a high level of flexibility and scalability. The technology is based on the belief that a complex process management system can be built by a set of static and process-based function modules. Each of the function modules consists of a set of categorized elements to meet the desired functional requirements. These categorized elements can be extracted into a unified process model upon which a configurable modular can be developed. The modular can be configured into a desired function module with specific functional requirements. The assignment of the function modules to the specific roles at the lifecycle processes forms a system. The technology has been successfully applied in a company specializing in make-to-order operations.

Design collaboration is recognized as an effective approach in joint problem solving to achieve success of product development in distributed and heterogeneous environments. Design collaboration involves communication of design information, coordination of design activities, and negotiation of design conflicts between multi-disciplinary teams. To support these critical requirements in collaborative design, methodologies and software systems are needed. This paper shares our experience in the method and software development for a Web-enabled engineering object modeling environment. It presents our methods for interoperable and extensible design information modeling, for intelligent object behaviors embedment in CAD models, and for design information sharing across product lifecycle applications through a common vocabulary. The prototype implementation of the modeling environment provides standardized and localized engineering objects embedded with design semantics and intelligent behaviors for the information needs from multiple engineering software applications. The prototype also provides activity coordination and negotiation facilities through team setting, online visualization, live updating, conflict management, and messaging. Use scenarios are discussed in the paper.Copyright © 2005 by ASME

Product design needs great team efforts from multi-disciplinary participants, even external partners, for collaborative problem solving. Design conflicts within and between functional teams do occur in such a collaborative design process. Detection and resolution of design conflicts through design conformance checking therefore becomes a critical activity in the joint design problem solving. This paper presents the development of a J2EE application prototype to support the STEP-based design conformance checking. A STEP-compliant information model has been specified to represent 3D CAD objects and other design information, while a knowledge representation model been proposed to describe design rules and constraints. The STEP objects and rule objects are managed and processed by the enterprise Java beans of a J2EE application server, which continuously applies the rule objects to the STEP objects and finally draws a conclusion for the design conformance checking. Application scenarios are discussed in the paper to illustrate the effectiveness of both the STEP/rule objects modeling approaches and the prototype system for support of the design compliance checking in distributed environment.Copyright © 2004 by ASME

It is well recognized that conceptual design is the most critical stage of product development process. Yet, existing MEMS (Micro-Electro-Mechanical Systems) design synthesis models or methods are very restrictive in supporting MEMS conceptual design, in that they are only applicable to specific or specific types of designs, where building blocks for design synthesis have to be pre-specified by the designers. To address this problem, this paper proposes a MEMS conceptual design synthesis framework, which consists of a behavior representation that caters for the multidisciplinary MEMS design characteristics and a design synthesis strategy that is able to explore multidisciplinary phenomena for the development of MEMS initial design concepts. The behavior representation incorporates information of both physical interactions and chemical/biological/other reactions that take place during a MEMS device’s behavioral process. The design synthesis is accomplished by both forward and backward synthetic search strategies in identifying the relevant phenomena for the development of the desired behavioral processes. The framework can be used to develop both the physical structure of a MEMS device and the substances that are necessary for the chemical/biological/other reactions. A software prototype implementing the proposed framework is also presented, followed by a MEMS design case study.

A Web-based prototype system has been setup for users to carry out visualization-based manipulations and process planning of design models to support distributed design and manufacturing analysis. The process planning module, which has been deployed as services in the Internet, includes four intelligent approaches, and a Tabu search-based approach is explained to illustrate the optimization process. The Web-based system has been integrated with a distributed feature-based design system, and the latter can generate design models and re-represent them in an XML representation based on VRML and attributes of features to provide the input of the former. Through effective utilization of the Web and Java technologies, this system is independent of the operating system, scalable and service-oriented, and can be used by a geographically distributed design team to organize concurrent engineering design activities effectively.

The traditional product development strategy has shifted from first-to-market to right-to-market and the product development paradigm has also evolved from procedure-focused to customer-needs-fulfillment-focused. How to develop the product that really meets customers’ wants and provides “tailor-made” features for individual needs is critical in contemporary product development. To avoid the product development behind schedule, over budget, possible runaway, or not the product customer wants, the design requirements are critical design information, which should always be available for easily accessing, retrieving, updating, changing, sharing and re-using in product development lifecycle since they drive and navigate the design activities and are used as the yardsticks or crietria to evaluate, verify and validate design solutions. To achieve this goal, the design requirements should be efficiently modeled and managed. In this paper, the modeling and management of design requirements are addressed. Foremost, the models of modeling and management processes are proposed and the detailed definitions are articulated. The issues in each process are presented and how to address them is proposed. From system point of view, a system framework is orchestrated and the components under the framework and their relationships are then delineated. A system information and process flow is presented and how to embed and package the developed technologies into a system is illustrated via the system information and process flow and GUIs.

Methane (CH sub 4) emissions from rice fields were monitored in Hangzhou, China, from 1995 to 1998 by an automatic measurement system based on the "closed chamber technique." The impacts of water management, organic inputs, and cultivars on CH sub 4 emission were evaluated. Under the local crop management system, seasonal emissions ranging from 53 to 557 kg CH sub 4 ha high -1 were observed with an average value of 182 kg CH sub 4 ha high -1. Methane emission patterns differed among rice seasons and were generally governed. by temperature changes. Emissions showed an increasing trend in early rice and a decreasing trend in late rice. In a single rice field, CH sub 4 emissions increased during the first half of the growing period and decreased during the second half. Drainage was a major modifier of seasonal CH sub 4 emission pattern. The local practice of midseason drainage reduced CH sub 4 emissions by 44 % as compared with continuous flooding; CH sub 4 emissions could further be reduced by intermittent irrigation, yielding a 30 % reduction as compared with midseason drainage. The incorporation of organic amendments promoted CH sub 4 emission, but the amount of emission varied with the type of organic material and application method. Methane emission from fields where biogas residue was applied was 10 - 16 % lower than those given the same quantity (based on N content) of pig manure. Rice straw applied before the winter fallow period reduced CH sub 4 emission by 11 % as compared with that obtained from fields to which the same amount of rice straw was applied during field preparation. Broadcasting of straw instead of incorporation into the soil showed less emission (by 12 %). Cultivar selection influenced CH sub 4 emission, but the differences were smaller than those among organic treatments and water regimes. Modifications in water regime and organic inputs were identified as promising mitigation options in southeast China.

Basing on new regularization-renormalization method, the $\lambda\phi^4$ model used in standard model is studied both perturbatively and nonperturbatively (by Gaussian effective potential). The invariant property of two mass scales is stressed and the existence of a (Landau) pole is emphasized. Then after coupling with the SU(2)$\times$U(1) gauge fields, the Higgs mass in standard model (SM) can be calculated as $m_H\approx$138GeV. The critical temperature ($T_c$) for restoration of symmetry of Higgs field, the critical energy scale ($\mu_c$, the maximum energy scale under which the lower excitation sector of the GEP is valid) and the maximum energy scale ($\mu_{max}$, at which the symmetry of the Higgs field is restored) in the standard model are $T_c\approx$476 GeV, $\mu_c\approx 0.547\times 10^{15}$GeV and $\mu_{\max}\approx 0.873 \times 10^{15}$ GeVv respectively., Comment: 12 pages, LaTex, no figure

Sudden death is a common complication of myocardial infarction, necrotic pancreatitis and other diseases. Physicians usually neglect the possibility of neurological disorders. 59 cases of sudden death among 314 autopsied cases with neurological diseases were analyzed. The most frequent cause of neurological sudden death was cerebrovascular disease (CVD). It was present in 53 (89.9%) cases. 48 of them had hemorrhagic CVD. 37 of these 48 cases were due to hypothalamic lesions. In 37 cases general autopsy was performed; pathological abnormalities of heart, lungs, stomach etc, were found in 28 of them. In conclusion, the size and location of the lesion correlated with the prognosis of the disease. Concomitant multiple organ damage may deteriorate the lesion. Awareness of sudden death resulting from CVD may elevate the rate of correct diagnosis.

One of the challenging problems that hinder the development of collaborative design systems is the contradiction of large CAD files and the limited speed to share them over the Internet and Web. 3D streaming technique, which can allow effective and efficient dispatch and access of large-volume CAD data as a series of patched streams across the Internet, provides a promising solution to overcome the obstacle. Geometric simplification (or decimation) of 3D models is the key algorithm to realize the streaming technique. In this paper, a new geometric simplification algorithm has been developed, in which two criteria are the crucial elements to control the collapse process for edges in 3D VRML models to reduce the amount of information. The major feature of the algorithm is that it has incorporated some advantages of the previously developed vertex decimation approach and edge collapse approach. Meanwhile, the mechanism of adaptive threshold parameters adopted in this work enhances the adaptability of the algorithm for various applications. Through case studies and comparisons with some related works, the algorithm shows good performance and potentials in terms of efficiency, adaptability and robustness.Copyright © 2005 by ASME