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71.
Eugenio CapraAuthor Vitae Chiara FrancalanciAuthor Vitae 《Journal of Systems and Software》2011,84(1):144-161
Open Source (OS) was born as a pragmatic alternative to the ideology of Free Software and it is now increasingly seen by companies as a new approach to developing and making business upon software. Whereas the role of firms is clear for commercial OS projects, it still needs investigation for projects based on communities. This paper analyses the impact of firms’ participation on popularity and internal software design quality for 643 SourceForge.net projects. Results show that firms’ involvement improves the ranking of OS projects, but, on the other hand, puts corporate constraints to OS developing practices, thus leading to lower structural software design quality. 相似文献
72.
Standard process monitoring and traceability programming in collaborative CAD/CAM/CNC manufacturing scenarios 总被引:1,自引:0,他引:1
Julio Garrido CamposAuthor Vitae Luis Rodriguez MiguezAuthor Vitae 《Computers in Industry》2011,62(3):311-322
The paper focuses on collaborative STEP-based CAD/CAM/CNC supply chains to program and automate machining process data monitoring and traceability activities. A traceability interface (traceability nc_functions) is defined for the new CNC programming standard ISO STEP-NC. CAM systems will be able to program monitoring and data access activities by inserting traceability nc_function calls in CNC programs. On the shop floor, controllers will automatically interpret these nc_functions to access process data while machining and will relate data records with the corresponding machining operations in a STEP-NC part program. With both types of information—process data and standard machining program (STEP-NC part program)—spread and technologically heterogeneous engineering systems will have full knowledge about what has happened in production. Traceability data access automation will assure data reliability. The paper describes a traceability scenario where standards such as MTConnect and ISA-95 support, rather than interfere with, the STEP-NC traceability proposal. 相似文献
73.
Azzurra Ragone Tommaso Di Noia Eugenio Di Sciascio Francesco M. Donini 《Autonomous Agents and Multi-Agent Systems》2008,16(3):249-270
We present a novel logic-based framework to automate multi-issue bilateral negotiation in e-commerce settings. The approach
exploits logic as communication language among agents, and optimization techniques in order to find Pareto-efficient agreements.
We introduce , a propositional logic extended with concrete domains, which allows one to model relations among issues (both numerical and
non-numerical ones) via logical entailment, differently from well-known approaches that describe issues as uncorrelated. Through
it is possible to represent buyer’s request, seller’s supply and their respective preferences as formulas endowed with a
formal semantics, e.g., “if I spend more than 30000 € for a sedan then I want more than a two-years warranty and a GPS system included”. We mix logic and utility theory in order to express preferences in a qualitative and quantitative way. We illustrate the
theoretical framework, the logical language, the one-shot negotiation protocol we adopt, and show we are able to compute Pareto-efficient
outcomes, using a mediator to solve an optimization problem. We prove the computational adequacy of our method by studying
the complexity of the problem of finding Pareto-efficient solutions in our setting. 相似文献
74.
Davies BL Rodriguez y Baena FM Barrett AR Gomes MP Harris SJ Jakopec M Cobb JP 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2007,221(1):71-80
A brief history of robotic systems in knee arthroplasty is provided. The place of autonomous robots is then discussed and compared to more recent 'hands-on' robotic systems that can be more cost effective. The case is made for robotic systems to have a clear justification, with improved benefits compared to those from cheaper navigation systems. A number of more recent, smaller, robot systems for knee arthroplasty are also described. A specific example is given of an active constraint medical robot, the ACROBOT system, used in a prospective randomized controlled trial of unicondylar robotic knee arthroplasty in which the robot was compared to conventional surgery. The results of the trial are presented together with a discussion of the need for measures of accuracy to be introduced so that the efficacy of the robotic surgery can be immediately identified, rather than have to wait for a number of years before long-term clinical improvements can be demonstrated. 相似文献
75.
ABSTRACT Mexico is a large developing country, much of which is arid and semiarid. With a population of more than 81 million, Mexico is confronted with growing water scarcity and serious pollution of much of its surface water The National Water Commission (Comision Nacional del Agua—CNA) has embarked on a major program of modernization of water management. The water quality program, now consisting of 564 surface water stations (plus 239 groundwater stations), has no strategic design, has major data gaps, is not representative of important areas, is often unreliable, does not contain data for many current issues such as organic contaminants, and suffers from out-of-date or lack of facilities. Because the existing network is not representative of the range of issues for which data are needed, network redesign began from first principles rather than as an optimization of the existing network. The new program is built around client needs, and uses four components—a primary network of some 200 stations that are designed to characterize important water bodies over the long term; a flexible secondary network that focuses on effluent regulatory issues; surveys and special studies for river basin planning and issue-specijic purposes; and a mobile emergency capability. Modernization of the water quality program also includes parallel activities focusing on training, institutional, and legal issues. 相似文献
76.
For the last 6 years we have been using Miconazole cream in the treatment of tinea and vaginal candidiasis. We think that it is at least as good as the best drugs for this purpose, but consider it difficult to decide about its superiority. Therefore we refrain from describing this part of our experience in detail. We have employed Miconazole "per os" at the daily doses of 24-28 mg./kg. in treating 3 cases of tinea corporis or cruris by "Trichophyton rubrum". Symptoms ceased in 3 days; mycologic examination turned negative in 2 weeks; treatment ended in apparent cure in 3 weeks. We have employed Miconazole "per venam" and "per os" in the treatment of: mycetomata (2) by "Streptomyces somaliensis", without success; mycetoma by "Madurella grisea" (1), without success; chromomycosis by a 5-flucytosine resistant strain of "Cladosporium carrionii" (1), without success; paracoccidioidosis (5) with lesions in mouth and lungs, with good results; leishmaniasis by "Leishmania brasiliensis" (1), without success; mucocutaneous disseminated candidiasis (1), with very good results. Tolerance has been excellent: but pruritus appeared from the third week with 600 or more mg. "per venam", in several patients. Doses varied between 10 and 50 mg./kg./day. One patient, who suffered with candidiasis, is taking 50 to 30 mg./kg./day since more than a year ago and, being a child, he is feeling well and growing to be normal. We recommend employing Miconazole against systemic canidiasis, sulpharesistant paracoccidioidosis and assaying it further in tinea (at least, in griseofulvin-resistant cases). 相似文献
77.
Grybos P. Rodriguez A.E.C. Idzik M. Gaitan J.L. Prino F. Ramello L. Swientek K. Wiacek P. 《IEEE transactions on nuclear science》2005,52(4):839-846
We report on the multichannel IC (RX64DTH) designed for position sensitive X-ray measurements with silicon strip detectors and dedicated to medical imaging applications. This integrated circuit has a binary readout architecture with a double threshold allowing on selection energy window for measured signals. The design was realized in a 0.8 /spl mu/m CMOS process. The core of the RX64DTH IC consists of 64 readout channels. The single channel is built with four basic blocks: charge sensitive preamplifier, shaper, two independent discriminators, and two independent 20-bit counters. Each readout channel counts pulses which are above the low discriminator threshold and counts pulses independently above the high discriminator threshold. The energy resolution in such architecture is limited by the noise of a single channel and by channel to channel threshold spread. We present the noise and matching performance of a 384-channel module built with a silicon strip detector and six RX64DTH ICs. In the 384-channel module an equivalent noise charge of about 200 el. rms is achieved for the shaper peaking time of 0.8 /spl mu/s and strip capacitance of 3 pF. The deviation of discriminator thresholds for the whole system is only 87 el. rms. The obtained results show that the energy resolution and uniformity of analog parameters (noise, gain, offset) are sufficient for medical diagnostic applications such as dual energy mammography and angiography. 相似文献
78.
Ferro R. Rodriguez J.A. Jimenez I. Cirera A. Cerda J. Morante J.R. 《IEEE sensors journal》2005,5(1):48-52
A novel NO/sub 2/ sensor based on (CdO)/sub x/(ZnO)/sub 1-x/ mixed-oxide thin films deposited by the spray pyrolysis technique is developed. The sensor response to 3-ppm NO/sub 2/ is studied in the range 50/spl deg/C-350/spl deg/C for three different film compositions. The device is also tested for other harmful gases, such as CO (300 ppm) and CH/sub 4/ (3000 ppm). The sensor response to these reducing gases is different at different temperatures varying from the response typical for the p-type semiconductor to that typical for the n-type semiconductor. Satisfactory response to NO/sub 2/ and dynamic behavior at 230/spl deg/C, as well as low resistivity, are observed for the mixed-oxide film with 30% Cd. The response to interfering gas is poor at working temperature (230/spl deg/C). On the basis of this study, a possible sensing mechanism is proposed. 相似文献
79.
Jose M. Armingol Javier Otamendi Arturo de la Escalera Jose M. Pastor Francisco J. Rodriguez 《Journal of Intelligent and Robotic Systems》2003,37(3):321-336
Machine vision technology improves productivity and quality management and provides a competitive advantage to industries that employ this technology. In this article, visual inspection and quality control theory are combined to develop a robust inspection system with manufacturing applications. The inspection process might be defined as the one used to determine if a given product fulfills a priori specifications, which are the quality standard. In the case of visual inspection, these specifications include the absence of defects, such as lack (or excess) of material, homogeneous visual aspect, required color, predetermined texture, etc. The characterization of the visual aspect of metallic surfaces is studied using quality control chars, which are a graphical technique used to compare on-line capabilities of a product with respect to these specifications. Original algorithms are proposed for implementation in automated visual inspection applications with on-line execution requirements. The proposed artificial vision method is a hybrid between the two usual methods of pattern comparison and theoretical decision. It incorporates quality control theory to statistically model the pattern for defect-free products. Specifically, individual control charts with 6-sigma limits are set so the inspection error is minimized. Experimental studies with metallic surfaces help demonstrate the efficacy and robustness of the proposed methodology. 相似文献
80.
Penin L.F. Balaguer C. Pastor J.M. Rodriguez F.J. Barrientos A. Aracil R. 《Robotics & Automation Magazine, IEEE》1998,5(3):18-29
A robotic manufacturing cell of pre-fabricated glass reinforced cement panels for construction industry has been developed by DISAM for the Spanish construction company Dragados, SA. The main contribution of the developed system is the automatic programming and control of the whole plan. The architect's 3D-drawing of the building facade done on a CAD system serves as input. From the CAD design, the optimum facade to panels partition is obtained. In order to manufacture each panel, automatic task and path planning are performed for the equipment present in the manufacturing cell: spraying robot, PLCs, control computer, etc 相似文献