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Herein, the assessment of commercial beef and chicken bouillons in terms of heterocyclic aromatic amines (HAAs) and some of their precursors was evaluated. Creatine and creatinine levels were ranged between 0.57–0.80 and 0.28–0.94 mg g−1, respectively. Glutamic acid was found to be the most abundant amino acid in both bouillons. 2-amino-3,7,8-trimethylimidazo[4,5-ƒ]quinoxaline (7,8-DiMeIQx, up to 0.03 ng g−1) was the only quantified analyte in beef bouillons, whereas it (up to 0.08 ng g−1) was determined in addition to 2-amino-3-methylimidazo[4,5-ƒ]quinoxaline (IQx, up to 0.08 ng g−1) in chicken bouillons. Creatine, creatinine and free amino acid composition did not have the capacity to initiate the formation of HAAs. Therefore, bouillons do not pose risk in terms of HAAs. However, it should be noted that multiple factors, such as the substrate amount and production conditions, may affect the results. Glutamic acid content is remarkable in commercial bouillons sold in Turkey. 相似文献
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The phase behavior and volumetric properties of polyethylene (PE) in solutions of n‐pentane and n‐pentane/CO2 were studied in a temperature (T) range of 370–440 K at pressures up to 60 MPa. Measurements were conducted with a variable‐volume view‐cell system equipped with optical sensors to monitor the changes in the transmitted light intensity as the P or the T of the system was changed. Lower‐critical‐solution‐temperature‐type behavior was observed for all of the liquid–liquid (L–L) phase boundaries, which shifted to higher pressures in solutions containing CO2. The solid–fluid (S–F) phase boundaries were investigated over a P range of 8–54 MPa and took place in a narrow T range, from 374 to 378 K in this P interval. The S–F phase boundary showed a unique feature in that the demixing temperatures showed both increasing and decreasing trends with P depending on the P range. This was observed in both the PE/n‐pentane and PE/n‐pentane/CO2 mixtures. The density of these solutions were measured as a function of P at selected temperatures or as a function of T at selected pressures that corresponded to the paths followed in approaching the phase boundaries (S–F or L–L) starting from a homogeneous one‐phase condition. The data showed a smooth variation of the overall mixture density along these paths. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2201–2209, 2003 相似文献
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Qingbin Cui Mehmet Emre Bayraktar Makarand Hastak Issam Minkarah 《Canadian Metallurgical Quarterly》2004,20(3):118-125
Since the introduction of warranty provisions in federal highway jobs, more and more state departments of transportation (DOTs) have considered the use of such provisions to protect their initial investment. This paper describes the pros and cons of warranty contracting in highway construction based on a survey of warranty practices in the United States. In particular, the need for state DOTs to buy a warranty for a well-built project is questioned. As an alternative, this paper introduces the warranty option, which gives the DOT the right to buy a warranty only if it becomes necessary at the end of construction. This option is exercised if the performance on site warrants it. This paper describes the mechanics of the warranty option and its advantages over the conventional warranty. A bid evaluation model is also developed for the warranty option approach. 相似文献
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Dynamic stability of the torsional vibrations of a shaft system consisting of two torsionally elastic shafts interconnected through a Hooke's joint is investigated by means of a two degree-of-freedom model. The linearized equations of motion are shown to consist of a set of Mathieu-Hill equations and stability of their solutions is analyzed by means of a monodromy matrix method. Results are presented in the form of stability charts constructed on various parameter planes visualizing the effect of various selected pairs of system parameters on the stability. 相似文献
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Björn Labitzke Serkan Bayraktar Andreas Kolb 《Data mining and knowledge discovery》2013,27(1):117-145
Multi- and hyperspectral imaging and data analysis has been investigated in the last decades in the context of various fields of application like remote sensing or microscopic spectroscopy. However, recent developments in sensor technology and a growing number of application areas require a more generic view on data analysis, that clearly expands the current, domain-specific approaches. In this context, we address the problem of interactive exploration of multi- and hyperspectral data, consisting of (semi-)automatic data analysis and scientific visualization in a comprehensive fashion. In this paper, we propose an approach that enables a generic interactive exploration and easy segmentation of multi- and hyperspectral data, based on characterizing spectra of an individual dataset, the so-called endmembers. Using the concepts of existing endmember extraction algorithms, we derive a visual analysis system, where the characteristic spectra initially identified serve as input to interactively tailor a problem-specific visual analysis by means of visual exploration. An optional outlier detection improves the robustness of the endmember detection and analysis. An adequate system feedback of the costly unmixing procedure for the spectral data with respect to the current set of endmembers is ensured by a novel technique for progressive unmixing and view update which is applied at user modification. The progressive unmixing is based on an efficient prediction scheme applied to previous unmixing results. We present a detailed evaluation of our system in terms of confocal Raman microscopy, common multispectral imaging and remote sensing. 相似文献
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A color-based face tracking algorithm is proposed to be used as a human-computer interaction tool on mobile devices. The solution
provides a natural means of interaction enabling a motion parallax effect in applications. The algorithm considers the characteristics
of mobile use-constrained computational resources and varying environmental conditions. The solution is based on color comparisons
and works on images gathered from the front camera of a device. In addition to color comparisons, the coherency of the facial
pixels is considered in the algorithm. Several applications are also demonstrated in this work, which use the face position
to determine the viewpoint in a virtual scene, or for browsing large images. The accuracy of the system is tested under different
environmental conditions such as lighting and background, and the performance of the system is measured in different types
of mobile devices. According to these measurements the system allows for accurate (7% RMS error) face tracking in real time
(20–100 fps). 相似文献
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Quality function deployment (QFD) is a systematic process for translating customer needs into engineering characteristics, and then communicating them throughout the enterprise in a way to ensure that details are quantified and controlled. The inherent fuzziness of relationships in QFD modeling justifies the use of fuzzy regression for estimating the relationships between both customer needs and engineering characteristics, and among engineering characteristics. Albeit QFD aims to maximize customer satisfaction, requirements related to enterprise satisfaction such as cost budget, extendibility, and technical difficulty also need to be considered. This paper presents a fuzzy multiple objective decision framework that includes not only fulfillment of engineering characteristics to maximize customer satisfaction, but also maximization of extendibility and minimization of technical difficulty of engineering characteristics as objectives subject to a financial budget constraint to determine target levels of engineering characteristics in product design. A real-world quality improvement problem is presented to illustrate the application of the decision approach. 相似文献