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排序方式: 共有1016条查询结果,搜索用时 15 毫秒
51.
Margot J. Hutchins Stefanie L. RobinsonAuthor VitaeDavid DornfeldAuthor Vitae 《Journal of Manufacturing Systems》2013
Developing sustainable products and processes is growing in importance due to increasing regulation, consumer interest, access to information, and competitive forces. In order to adequately evaluate the sustainability of products and processes, there is a need to consider the impacts from all three pillars of sustainability – society, environment, and economics. There are substantial challenges to identifying and understanding the social impacts associated with manufacturing activities. This paper provides a framework for characterizing the social impacts of manufacturing throughout the life cycle of a product or process. Social impacts occur on various scales in manufacturing, from the level of a unit process to the level of the enterprise. Additionally, manufacturing activities impact consumers, communities, and larger political/spatial realms. This paper identifies key characteristics of social impacts associated with manufacturing that should be considered to more effectively address the social dimension of sustainability for products and processes. Examples involving a typical manufacturing process – welding – are presented to illustrate the utility of the framework. 相似文献
52.
Three-dimensional human shape inference from silhouettes: reconstruction and validation 总被引:1,自引:0,他引:1
Jonathan Boisvert Chang Shu Stefanie Wuhrer Pengcheng Xi 《Machine Vision and Applications》2013,24(1):145-157
Silhouettes are robust image features that provide considerable evidence about the three-dimensional (3D) shape of a human body. The information they provide is, however, incomplete and prior knowledge has to be integrated to reconstruction algorithms in order to obtain realistic body models. This paper presents a method that integrates both geometric and statistical priors to reconstruct the shape of a subject assuming a standardized posture from a frontal and a lateral silhouette. The method is comprised of three successive steps. First, a non-linear function that connects the silhouette appearances and the body shapes is learnt and used to create a first approximation. Then, the body shape is deformed globally along the principal directions of the population (obtained by performing principal component analysis over 359 subjects) to follow the contours of the silhouettes. Finally, the body shape is deformed locally to ensure it fits the input silhouettes as well as possible. Experimental results showed a mean absolute 3D error of 8 mm with ideal silhouettes extraction. Furthermore, experiments on body measurements (circumferences or distances between two points on the body) resulted in a mean error of 11 mm. 相似文献
53.
The case of a 36-year-old man who sought treatment of right facial myokymia and spastic paretic facial contracture is reported. Computed tomography and magnetic resonance imaging revealed a tumor located in the right cerebellar peduncle and the right dorsal pons bulging into the fourth ventricle. After microsurgical partial resection of the mass, which was verified histologically as an anaplastic glioma, facial myokymia initially ceased. The vermicular rippling movements were less intense upon recurrence and could be controlled by low-dose dexamethasone in the further course, when magnetic resonance imaging showed an interstitial pontine edema after percutaneous radiation therapy. It is assumed that facial myokymia and spastic paretic facial contracture were generated by ectopic activity due to alterations in the microenvironment at the intrapontine portion of the axons of the seventh nerve caused by the compressive effect of the tumor and later by edema. 相似文献
54.
In vitro β‐Carotene Bioaccessibility and Lipid Digestion in Emulsions: Influence of Pectin Type and Degree of Methyl‐Esterification 下载免费PDF全文
Tina A.J. Verrijssen Stefanie Christiaens Sarah H.E. Verkempinck Jeroen Boeve Tara Grauwet Ann M. Van Loey Laura Salvia‐Trujillo Marc E. Hendrickx 《Journal of food science》2016,81(10):C2327-C2336
Citrus pectin (CP) and sugar beet pectin (SBP) were demethoxylated and fully characterized in terms of pectin properties in order to investigate the influence of the pectin degree of methyl‐esterification (DM) and the pectin type on the in vitro β‐carotene bioaccessibility and lipid digestion in emulsions. For the CP based emulsions containing β‐carotene enriched oil, water and pectin, the β‐carotene bioaccessibility, and lipid digestion were higher in the emulsions with pectin with a higher DM (57%; “CP57 emulsion”) compared to the emulsions with pectin with a lower DM (30%; “CP30 emulsion”) showing that the DM plays an important role. In contrast, in SBP‐based emulsions, nor β‐carotene bioaccessibility nor lipid digestion were dependent on pectin DM. Probably here, other pectin properties are more important factors. It was observed that β‐carotene bioaccessibility and lipid digestion were lower in the CP30 emulsion in comparison with the CP57, SBP32, and SBP58 emulsions. However, the β‐carotene bioaccessibility of CP57 emulsion was similar to that of the SBP emulsions, whereas the lipid digestion was not. It seems that pectin type and pectin DM (in case of CP) are determining which components can be incorporated into micelles. Because carotenoids and lipids have different structures and polarities, their incorporation may be different. This knowledge can be used to engineer targeted (digestive) functionalities in food products. If both high β‐carotene bioaccessibility and high lipid digestion are targeted, SBP emulsions are the best options. The CP57 emulsion can be chosen if high β‐carotene bioaccessibility but lower lipid digestion is desired. 相似文献
55.
56.
Gerhard?Sinn Herwig?MayerEmail author Stefanie?Stanzl-Tschegg 《Journal of Materials Science》2005,40(16):4325-4332
Surfaces created by ultrasonic-assisted cutting (UC) of beech and spruce and of medium density fibreboard (MDF) are compared to surfaces obtained by conventional linear cutting (CC) using a sharp tool. Topography is evaluated performing roughness measurements and scanning electron microscopy. No effect of UC procedure on mean roughness is found. The surface of MDF and large areas of the surfaces of the woods appear similar after UC and CC, whereas other regions show impact marks and microscopic reels produced by the periodic oscillation of the tool in UC. The wettability of surfaces produced with both wood processing techniques is similar. Surface free energy measurements indicate accelerated ageing caused by UC, probably due to heating. 相似文献
57.
Microfluidic Templated Multicompartment Microgels for 3D Encapsulation and Pairing of Single Cells 下载免费PDF全文
Liyuan Zhang Kaiwen Chen Haoyue Zhang Bo Pang Chang‐Hyung Choi Angelo S. Mao Hongbing Liao Stefanie Utech David J. Mooney Huanan Wang David A. Weitz 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(9)
Controlled encapsulation and pairing of single cells within a confined 3D matrix can enable the replication of the highly ordered cellular structure of human tissues. Microgels with independently controlled compartments that can encapsulate cells within separately confined hydrogel matrices would provide precise control over the route of pairing single cells. Here, a one‐step microfluidic method is presented to generate monodisperse multicompartment microgels that can be used as a 3D matrix to pair single cells in a highly biocompatible manner. A method is presented to induce microgels formation on chip, followed by direct extraction of the microgels from oil phase, thereby avoiding prolonged exposure of the microgels to the oil. It is further demonstrated that by entrapping stem cells with niche cells within separate but adjacent compartments of the microgels, it can create complex stem cell niche microenvironments in a controlled manner, which can serve as a useful tool for the study of cell–cell interactions. This microfluidic technique represents a significant step toward high‐throughput single cells encapsulation and pairing for the study of intercellular communications at single cell level, which is of significant importance for cell biology, stem cell therapy, and tissue engineering. 相似文献
58.
Stefanie Bußmann Harald Kruggel-Emden Mathis Reichert 《Advanced Powder Technology》2021,32(7):2171-2191
The particle based Discrete Element Method (DEM) can be applied to examine comminution processes. In this study, a DEM framework has been extended to model particle breakage without mass loss. After a breakage event occurs, spherical particles, as often considered in the DEM, are replaced by size reduced spherical fragments. During the following time steps, the fragments grow to their desired sizes, so that the mass loss can be counterbalanced. Previously defined overlaps with adjacent unbroken and broken particles (fragments) as well as walls are allowed. The breakage model has been realized in a parallelized DEM framework because comminution processes are often attributed to large numbers of particles and by parallelization the computational time can be reduced efficiently. An oedometer (one-dimensional compression in axial direction of a confined particle bed) has been modelled to investigate the parallelization efficiency and the influence of the permitted overlaps during the growth process on the growth duration. A simplified roller mill has been considered to examine the applicability of the breakage procedure considering parallelization. The results show that parallelization reduces computational time considerably. The breakage procedure is suitable to model comminution processes involving even densely packed particle systems and is superior to existing approaches. 相似文献
59.
Kreutzer Jeffrey S.; Harris-Marwitz Jennifer; Myers Stefanie L. 《Canadian Metallurgical Quarterly》1990,4(4):249
Provides information about issues confronting neuropsychologists involved in brain injury litigation. Neuropsychologists are often involved as experts in the litigation process because of their unique role in assessment and treatment of brain injury sequelae. Focus is on evaluation, preparation of reports, testimony, professional credibility, ethics, and responsibilities to the patient. Criteria for evaluating the expertise and credentials of psychologists hired by attorneys are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Ali A. Moazzami Stefanie L. Haese Afaf Kamal‐Eldin 《European Journal of Lipid Science and Technology》2007,109(10):1022-1027
Sesame seed (Sesamum indicum L.) is a rich source of furofuran lignans with a wide range of potential biological activities. The major lignans in sesame seeds are the oil‐soluble sesamin and sesamolin, as well as glucosides of sesaminol and sesamolinol that reside in the defatted sesame flour. Upon refining of sesame oil, acid‐catalyzed transformation of sesamin to episesamin and of sesamolin to epimeric sesaminols takes place, making the profile of refined sesame oils different from that of virgin oils. In this study, the total lignan content of 14 sesame seeds ranged between 405 and 1178 mg/100 g and the total lignan content in 14 different products, including tahini, ranged between 11 and 763 mg/100 g. The content of sesamin and sesamolin in ten commercial virgin and roasted sesame oils was in the range of 444–1601 mg/100 g oil. In five refined sesame oils, sesamin ranged between 118 and 401 mg/100 g seed, episesamin between 12 and 206 mg/100 g seed, and the total contents of sesaminol epimers between 5 and 35 mg/100 g seed, and no sesamolin was found. Thus, there is a great variation in the types and amounts of lignans in sesame seeds, seed products and oils. This knowledge is important for nutritionists working on resolving the connection between diet and health. Since the consumption of sesame seed products is increasing steadily in Europe and USA, it is important to include sesame seed lignans in databases and studies pertinent to the nutritional significance of antioxidants and phytoestrogens. It is also important to differentiate between virgin, roasted and refined sesame oils. 相似文献