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1.
The relationship between endometriosis and infertility is observed frequently. Patients with both conditions require a conservative approach to their management. Since hormonal therapy is one of those approaches, we sought to compare the efficacy of Danazol and Gestrinone in 80 infertile patients (48 and 32, respectively). Therapy lasted 6 months in both treatment groups, and all patients studied had laboratory tests performed and were clinically evaluated and classified through laparoscopy before and after therapy. The improvement of symptoms and favorable follow-up were similar with both treatments. The reestablishment of menstrual patterns and fertility were also nearly alike in both groups. However, Gestrinone was associated with fewer secondary effects and is easier to administer than Danazol. We conclude that Gestrinone is a useful medication in the management of the infertile patient with endometriosis. 相似文献
2.
Mobile robotic systems must sense constraints imposed by a dynamically changing environment and predictably react to those changes in real-time. Complexity arises in mobile robotic systems because the computing platform travels through the environment with which the system is interacting. These systems have spatio-temporal requirements in the sense that correct behavior is defined in terms of both space and time. The focus of this paper is mobile robotic platforms that must sense their environment and avoid obstacles as they navigate from one point to another. We present a design and analysis methodology for these platforms that integrates spatio-temporal attributes with fixed priority real-time scheduling through the use of zone and processing window abstractions. 相似文献
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This work describes the development and testing of a system for measuring static pressure along the axis of supersonic flow devices such as convergent–divergent nozzles or ejectors. The pressure probe consists of a capillary tube positioned at the ejector centerline. A hole is perforated perpendicularly on the wall of the thin tube to capture and deport the static pressure measurement to a piezoelectric sensor located at one extremity of the tube outside the ejector. The measurements obtained are compared with numerical results from computational fluid dynamics simulations and wall pressure measurements. The first tests demonstrate the good capability of the pressure probe to detect shocks occurring in the flow and to provide continuous axial distributions of the static pressure. 相似文献
5.
Space heating load is decreasing in modern Finnish apartments due to lower U-values of the construction, tight envelopes and heat recovery from exhaust ventilation air. This makes it possible to develop a new combined low temperature water heating system with nominal supply/return water temperatures of 45 °C/35 °C. Such a system includes radiators in rooms and floor heating in bathrooms.In this study, the performance of an apartment building is determined by using dynamic simulation. The simulation results for the combined low temperature water heating system are compared with those for three conventional radiator and floor heating systems. The results show that the combined low temperature water heating system performs well and is able to maintain the zones within the required temperature levels. The thermal comfort analysis indicates that the drifts and ramps in operative temperature using the four studied heating systems are within the limits of Ashrae Standard 55-2004.Temperature measurements in a test room are carried out to find the vertical difference of air temperature using two methods: radiator heating and floor heating. These measurements indicate that there is only a small vertical temperature difference that would not produce any significant thermal discomfort. 相似文献
6.
Enric Menéndez Hiwa Modarresi Claire Petermann Josep Nogués Neus Domingo Haoliang Liu Brian J. Kirby Amir Syed Mohd Zahir Salhi Earl Babcock Stefan Mattauch Chris Van Haesendonck André Vantomme Kristiaan Temst 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(11)
The combination of lithography and ion implantation is demonstrated to be a suitable method to prepare lateral multilayers. A laterally, compositionally, and magnetically modulated microscale pattern consisting of alternating Co (1.6 µm wide) and Co‐CoO (2.4 µm wide) lines has been obtained by oxygen ion implantation into a lithographically masked Au‐sandwiched Co thin film. Magnetoresistance along the lines (i.e., current and applied magnetic field are parallel to the lines) reveals an effective positive giant magnetoresistance (GMR) behavior at room temperature. Conversely, anisotropic magnetoresistance and GMR contributions are distinguished at low temperature (i.e., 10 K) since the O‐implanted areas become exchange coupled. This planar GMR is principally ascribed to the spatial modulation of coercivity in a spring‐magnet‐type configuration, which results in 180° Néel extrinsic domain walls at the Co/Co‐CoO interfaces. The versatility, in terms of pattern size, morphology, and composition adjustment, of this method offers a unique route to fabricate planar systems for, among others, spintronic research and applications. 相似文献
7.
This work presents a formulation developed to add capabilities for representing the through thickness distribution of the transverse normal stresses, σz, in first and higher order shear deformable shell elements within a finite element (FE) scheme. The formulation is developed within a displacement based shear deformation shell theory. Using the differential equilibrium equations for two-dimensional elasticity and the interlayer stress and strain continuity requirements, special treatment is developed for the transverse normal stresses, which are thus represented by a continuous piecewise cubic function. The implementation of this formulation requires only C0 continuity of the displacement functions regardless of whether it is added to a first or a higher order shell element. This makes the transverse normal stress treatment applicable to the most popular bilinear isoparametric 4-noded quadrilateral shell elements.
To assess the performance of the present approach it is included in the formulation of a recently developed third order shear deformable shell finite element. The element is added to the element library of the general nonlinear explicit dynamic FE code DYNA3D. Some illustrative problems are solved and results are presented and compared to other theoretical and numerical results. 相似文献
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This work presents a computational material model for plain-woven fabric composite for use in finite element analysis. The material model utilizes the micro-mechanical approach and the homogenization technique. The micro-mechanical model consists of four sub-cells, however, because of the existing anti-symmetry only two sub-cells have to be homogenized for prediction of the elastic material properties. This makes the model computationally very efficient and suitable for large-scale finite element analysis. The model allows the warp and fill yarns not to be orthogonal in the plane of the composite ply. This gives the opportunity to model complex-shaped composite structures with different braid angles. General homogenization procedure is employed with two levels of property homogenization. The model is programmed in MATLAB software and the predicted material properties of different composite materials are compared and presented. The material model shows good capability to predict elastic material properties of composites and very good computational efficiency. 相似文献
10.
Ala Tabiei Romil Tanov 《International journal for numerical methods in engineering》2002,54(5):763-787
The contribution of this paper consists of new development of transverse shear stresses through the thickness and finding an expression for the critical time step for explicit time integration of layered shells. This work presents the finite element (FE) formulation and implementation of a higher‐order shear deformable shell element for dynamic explicit analysis of composite and sandwich shells. The formulation is developed using a displacement‐based third‐order shear deformation shell theory. Using the differential equilibrium equations and the interlayer requirements, special treatment is developed for the transverse shear, resulting in a continuous, piecewise quartic distribution of the transverse shear stresses through the shell thickness. Expressions are developed for the critical time step of the explicit time integration for orthotropic homogeneous and layered shells based on the developed third‐order formulation. To assess the performance of the present shell element, it is implemented in the general non‐linear explicit dynamic FE code DYNA3D. Several problems are solved and results are presented and compared to other theoretical and numerical results. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献