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81.
82.
Response surface methodology (RSM) was utilized to investigate the influence of the main emulsion composition; mixture of palm and medium-chain triglyceride (MCT) oil (6%–12% w/w), lecithin (1%–3% w/w), and Cremophor EL (0.5%–1.5% w/w) as well as the preparation method; addition rate (2–20 mL/min), on the physicochemical properties of palm-based nanoemulsions. The response variables were the three main emulsion properties; particle size, zeta potential and polydispersity index. Optimization of the four independent variables was carried out to obtain an optimum level palm-based nanoemulsion with desirable characteristics. The response surface analysis showed that the variation in the three responses could be depicted as a quadratic function of the main composition of the emulsion and the preparation method. The experimental data could be fitted sufficiently well into a second-order polynomial model. The optimized formulation was stable for six months at 4 °C.  相似文献   
83.
本文分析了自定义模板的意义、设计原则,并介绍了制作模板的基本方法和技巧。  相似文献   
84.

Thomas Jefferson believed that scientific research could lead to a fuller understanding of nature, while simultaneously addressing a persistent social problem of national or global interest. The two-fold ideals of this 'Jeffersonian research programme' fit well with the inherently practical aims of ergonomics science. However, in the past, basic and applied concerns have not always been well integrated in the discipline. This article makes a contribution, by proposing a novel metascientific framework consisting of a two-dimensional research space that addresses this problem. One dimension is methodological, representing the trade-off between experimental control and representativeness, while the other dimension is intentional, representing the trade-off between knowledge- and market-oriented purposes. The framework helps explain why it has frequently been difficult to integrate basic and applied concerns, and, at the same time, it shows that a Jeffersonian research programme for ergonomics science can be achieved by opening up degrees of freedom for research that have been comparatively unexplored. The importance of demonstrating contributions to fundamental understanding and to applied practice within the same research programme may be essential for survival and success in a climate of restricted research funding.  相似文献   
85.
Current robot programming approaches lack the intuitiveness required for quick and simple applications. As new robotic applications are being identified, there is a greater need to be able to programme robots safely and quickly. This paper discusses the use of an augmented reality (AR) environment for facilitating intuitive robot programming, and presents a novel methodology for planning collision-free paths for an n-d.o.f. (degree-of-freedom) manipulator in a 3D AR environment. The methodology is interactive because the human is involved in defining the free space or collision-free volume (CFV), and selecting the start and goal configurations. The methodology uses a heuristic beam search algorithm to generate the paths. A number of possible scenarios are discussed.  相似文献   
86.
This paper is providing a design and evaluation methodology for biomass utilization networks (B-NETs) planning in local areas. The methodology is an effort to integrate various exertions of many researchers as well as stakeholders in the biomass field including process technologies, local area classification and renewable energy mechanisms to design and evaluate B-NETs. The proposed design methodology has three steps: classification, problem formulation and suggesting solution methods. The core part of planning the B-NETs utilization methodology is the superstructure that is a super class model for the processes of biomass utilization networks that has to be built for the local area. The biomass utilization superstructure (BUSS) relates the biomass resources to their products, available processes, and possible future processes of utilization in static manner. Although the local area BUSS is static in nature, it shows the decision makers what kinds of B-NETs are, or can be, available in their area. It is important to note that for each super class process there exists a number of elemental technologies, or what we call unit process (UP), that can perform the job under the same condition with different processing constraint. To support the design and operation process a technological information infrastructure (TII) needs to be built to work as an information pool and simulation tool. With the support of TII and the BUSS different scenarios can be synthesized, analyzed and compared. Scenarios development enables the designer to check processing alternatives as well as biomass promotion mechanisms that fit the concerns of various stakeholders. The results of the methodology application can be given in the form of suggestions of a specific network class(es) or scenarios that can be applied in a class of localities with the same characteristics. Following to methodology configuration, a proposal for optimization methods is discussed and a case study for comparing biomass network scenarios in mountainous city is introduced.  相似文献   
87.
The wavelet-Galerkin method is applied to study the free vibration of a horizontally suspended catenary cable. Antiderivatives of the Daubechies compactly supported wavelets have been used with multilevel representations. Comparison between wavelet and Fourier methods is presented for natural frequencies, mode shapes, and dynamic tension of the cable. Both methods showed that they are converging fast in obtaining the natural frequencies and mode shapes. However, as the dynamic tension is obtained, the Fourier solution shows many oscillations and the existence of the Gibbs phenomenon at the cable supports, whereas, these oscillations do not appear in the wavelet solutions. Comparison is also made with the linear theory of cable vibration. Due to the inclusion of the inertia term of the longitudinal component in our solution, new modes have been found. Those modes are reverting but swapping modes in which the longitudinal displacement component is larger than the transverse displacement component.  相似文献   
88.
Qualitative case studies of innovative pedagogical practices using ICT   总被引:1,自引:0,他引:1  
Abstract The Second Instructional Technology in Education Study: Module 2 (SITES M2) is a series of qualitative studies that identify and describe innovative pedagogical practices in 28 participating countries that use technology. The project resulted in 174 case study reports of innovative practice that are currently being analysed. This paper describes the goals, research questions, and methodology for this study and provides a context for the other papers that are published in this issue. Given the large number of case studies, a combined qualitative and quantitative approach to the research is described.  相似文献   
89.
90.
建筑设计教学新模式探讨   总被引:2,自引:1,他引:1  
针对建筑设计教学现存在的若干突出问题,提出了新的教学模式,包括以设计方法教学取代类型建筑教学,强调教学过程与要求的阶段性,强化设计前期工作内容训练,探讨教学组织的科学等,同时以实际教学为例说明了模式的具体操作过程,并就有关问题进行了讨论。  相似文献   
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