Improvement of the Rotation Arch of the Posterior Interosseous Pedicle Flap Preserving Both Reverse Posterior and Anterior Interosseous Vascular Sources.

Abstract PURPOSE: The reverse posterior interosseous artery flap has several advantages, not sacrificing any major blood vessel, but its relatively short pedicle limits the use to cover defects up to the metacarpophalangeal joint. Our purpose is to demonstrate that the ligature of the anterior interosseous artery (AIA), proximal to the communicating branch with the posterior interosseous artery, leads to an improved flap rotation arch, preserving both vascular sources. METHODS: Sixteen fresh cadavers with latex perfusion were analyzed before and after our technique of elongation, and the so-obtained measures were standardized in "percentage of elongation of the pedicle." Eight patient with the loss of substance at the dorsal aspect of the hand have been treated with this technique, and results were evaluated in terms of flap survival and complication rates. RESULTS: The medium length of the pedicle in the normal flap was 10.8\u2009cm, and after the section of the AIA, the medium length of the pedicle was 13.6\u2009cm with a medium increase of 2.8\u2009cm. It means a medium increase of 24% of the length of the pedicle. In all patients treated, full coverage of the defect was obtained, and we did not experience major complications. CONCLUSIONS: This anatomical study supported by our clinical experience demonstrates that the use of the variant described above permits to reach more distal part of the hand without being afraid to stretch the pedicle because of the connection with the anastomotic arcades of the AIA at the wrist reducing the risk of ischemia of the flap

Crowd-Engineering: Managing Innovative Product Design by Widening Collaborations

Global contest has overwhelmed enterprises by the eager demand for products and services with high-tech features, along the entire product life cycle. Several companies reacted by developing the cooperation with high-tech firms. However, in the last decade, another revolutionary asset is emerging together with the worldwide networking evolution, namely the "Crowd-Engineering" (C-E): A huge, flexible and diversified human capital-made of individuals and consultants-available for companies to create their products and services. Together with these advantages, however, this asset calls for companies to face the complexity in the crowd management, selecting among competitive contributions and making all of them work effectively and efficiently. Therefore, there is an emerging need for methods and tools to manage C-E processes. This study presents a theoretical framework for managing and selecting crowd contributions along the whole New Product and service Development (NPD) project. Pros and cons of C-E applications are discussed

Weldability and monitoring of resistance spot welding of Q&P and TRIP steels

This work aims at investigating the spot weldability of a new advanced Quenching and Partitioning (Q&P) steel and a Transformation Induced Plasticity (TRIP) steel for automotive applications by evaluating the effects of the main welding parameters on the mechanical performance of their dissimilar spot welds. The welding current, the electrode tip voltage and the electrical resistance of sheet stack were monitored in order to detect any metal expulsion and to evaluate its severity, as well as to clarify its effect on spot strength. The joint strength was assessed by means of shear and cross tension tests. The corresponding fracture modes were determined through optical microscopy. The welding current is the main process parameter that affects the weld strength, followed by the clamping force and welding time. Metal expulsion can occur through a single large expulsion or multiple expulsions, whose effects on the shear and cross tension strength have been assessed. Longer welding times can limit the negative effect of an expulsion if it occurs in the first part of the joining process. The spot welds exhibit different fracture modes according to their strengths. Overall, a proper weldability window for the selected process parameters has been determined to obtain sound joints

Improvement of powertrain mechatronic systems for lean automotive manufacturing

In recent years, the increasing severity of emission standards forced car manufacturers to integrate vehicle powertrains with additional mechatronic elements, consisting in sensors, executors and controlling elements interacting with each other. However, the introduction of the best available ecological devices goes hand in hand with the legislation and/or limitations in different regional markets. Thus, the designers adapt the mechatronic system to the target emission standards of the produced powertrain. The software embedded into the Engine Control Unit (ECU) is highly customized for the specific configurations: variability in mechatronic systems leads to the development of several software versions, lowering the efficiency of the design phase. Therefore the employment of a standard for the communication among sensors, actuators and the ECU would allow the development of a unique software for different configurations; this would be beneficial from a manufacturing point of view, enabling the simplification of the design process. Obviously, the new software must still guarantee the proper level of feedbacks to the ECU to ensure the compliance with different emission standards and the proper engine behavior. The general software is adapted to the powertrain: according to the specific target emission standard, some control elements may not be necessary, and a part of the software may be easily removed. In this paper, starting from a real case-study, a more general methodology is proposed for configurations characterized by different powertrain sets and manufacturing line constraints. The proposed technique allows to maintain the accuracy of the control system and improve process efficiency at the same time, ensuring lean production and lowering manufacturing costs. A set of mathematical techniques to improve software efficacy is also presented: the resulting benefits are enhanced by software standardization, because the design effort may be shared by the largest possible number of applications

VISUALIZATION MODEL FOR PRODUCT LIFECYCLE MANAGEMENT

Product Lifecycle Management (PLM) demonstrated to be a good strategy for manufacturing enterprises. In spite of all the benefits it is not still clear how to implement it in industry. This article presents a visualization model of enterprise processes for a PLM system. It presents in a graphic way the main elements of a product lifecycle. The model identifies what is done (process, activities), when it is done (workflows), who does what (roles - skills) and how it can be done better (methods and tools). UML-RUP is used as representation technique. A case study, which analyzes the specification and inspection procedures of geometric tolerances according to the GPS approach, proves the convenience of this model for supporting PLM implementation

Efficient management of industrial electric vehicles by means of static and dynamic wireless power transfer systems

Industrial companies are moving toward the electrification of equipment and processes, in line with the broader energy transition taking place across the economy. Particularly, the energy efficiency and, consequently, the reduction of environmental pollution of intralogistics activities have become a competitive element and are now an actual research and development objective. A wireless power transfer is a contactless electrical energy transmission technology based on the magnetic coupling between coils installable under the ground level and a coil mounted under the vehicle floor, and it represents an excellent solution to decrease the demand for batteries by reducing vehicle downtimes during the recharge. This work aims to define a methodology to determine the optimal positioning of wireless charging units across the warehouse, both for static and dynamic recharging. To this aim, firstly, a mathematical model of the warehouse is proposed to describe transfers and storage/retrieval operations executed by the forklifts. Then, an integer linear programming problem is applied to find the best possible layout of the charging infrastructures. The optimal solution respects the energetic requirements given by the customer and minimizes the overall system cost. The proposed approach was applied to optimize the installation in a real-size warehouse of a tire manufacturing company. Several scenarios were computer generated through discrete event simulation in order to test the optimizer in different warehouse conditions. The obtained results show that integrated dynamic and static WPT systems ensure a constant state of charge of the electric vehicles during their operations

Star formation in Cometary globule 1: the second generation

C18O spectral line observations, NIR spectrosopy, narrow and broad band NIR imaging and stellar J,H,Ks photometry are used to analyse the structure of the archetype cometary globule 1 (CG 1) head and the extinction of stars in its direction. A young stellar object (YSO) associated with a bright NIR nebulosity and a molecular hydrogen object (a probable obscured HH-object), were discovered in the globule. Molecular hydrogen and Br_gamma line emission is seen in the direction of the YSO. The observed maximum optical extinction in the globule head is 9.2 magnitudes. The peak N(H2) column density and the total mass derived from the extinction are 9.0 10^21 cm-2 and and 16.7 Msun (d/300pc)^2. C18O emission in the globule head is detected in a 1.5'' by 4' area with a sharp maximum SW of the YSO. Three regions can be discerned in C18O line velocity and excitation temperature. Because of variations in the C18O excitation temperature the integrated line emission does not follow the optical extinction. It is argued that the variations in the C18O excitation temperatures are caused by radiative heating by NX Pup and interaction of the YSO with the parent cloud. No indication of a strong molecular outflow from the YSO is evident in the molecular line data. The IRAS point source 07178-4429 located in the CG 1 head resolves into two sources in the HIRES enhanced IRAS images. The 12 and 25 micron emission originates mainly in the star NX Puppis and the 60 and 100 micron emission in the YSO. The IRAS FIR luminosity of the YSO is 3.1 Lsun.Comment: Language checked v2. Accepted for publication in A&A. 16 pages, 20 figures. C18O data will be available electronicall