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1.
《Journal of dairy science》2022,105(11):8621-8637
Lactobacillus reuteri fortified camel milk infant formula (CMIF) was produced. The effect of encapsulation in different matrices (sodium alginate and galacto-oligosaccharides) via spray drying, simulated infant gastrointestinal digestion (SIGID), and storage conditions (temperature and humidity) on the viability of L. reuteri in CMIF and the physicochemical properties of CMIF were evaluated. Compared with free cells, probiotic cell viability was significantly enhanced against SIGID conditions upon encapsulation. However, L. reuteri viability in CMIF decreased after 60 d of storage, predominantly at higher storage humidity and temperature levels. At the end of the storage period, significant changes in the color values were observed in all CMIF, with a reduction in their greenness, an increase in yellowness, and a wide variation in their whiteness. Moreover, pH values and caking behavior of all CMIF stored at higher temperature (40°C) and humidity [water activity (aw) = 0.52] levels were found to be significantly higher than the samples stored under other conditions. Over 30 d of storage at lower humidity conditions (aw = 0.11 and 0.33) and room temperature (25°C), no significant increase in CMIF lipid oxidation rates was noted. Fourier-transform infrared spectroscopy analysis showed that, compared with the other storage conditions, CMIF experienced fewer changes in functional groups when stored at aw = 0.11. Microscopic images showed typical morphological characteristics of milk powder, with round to spherical-shaped particles. Overall, camel milk fortified with encapsulated L. reuteri can be suggested as a promising alternative in infant formula industries, potentially able to maintain its physicochemical characteristics as well as viability of probiotic cells when stored at low humidity levels (aw = 0.11) and temperature (25°C), over 60 d of storage. 相似文献
2.
大规模多输入多输出(Massive multiple input multiple output, Massive MIMO)系统采用最小均方误差(Minimum mean square error, MMSE)接收检测方法时存在矩阵求逆复杂度高的问题,已有较多降低复杂度的研究。在降低检测算法复杂度的同时,如何提高算法收敛速度和检测性能一直是人们关注的焦点。本文将对称加速超松弛(Symmetric accelerated over-relaxation, SAOR)迭代算法应用于Massive MIMO系统信号检测中,避免了复杂的矩阵求逆计算,实现了复杂度较最小均方误差算法降低了一个数量级。仿真结果表明,基于SAOR的检测方法通过较少的迭代次数就能逼近最小均方误差(Minimum mean square error, MMSE)算法的检测性能,为Massive MIMO系统中接收信号的快速检测提供了较好的实现方法。 相似文献
3.
无线体域网中传输的是与生命高度相关的敏感数据,身份认证是信息安全保护的第一道防线。现有的基于人体生物信息的身份认证方案存在信息难提取、偶然性大和误差性大的问题,基于传统密码学的认证方案需较大计算资源和能量消耗,并不适用于无线体域网环境。为此,在动态口令和非对称加密机制基础上,提出一种适用于无线体域网的动态口令双向认证轻量协议,并对其进行形式化分析。通过理论证明、SVO逻辑推理及SPIN模型检测得出:该协议满足双向认证,且能够抵御重放攻击、伪装攻击、拒绝服务器攻击和口令离线攻击,具有较高安全性。 相似文献
4.
5.
Hedley Smyth Laurence Lecoeuvre Philippe Vaesken 《International Journal of Project Management》2018,36(1):170-183
The research analyses decisions as evaluative outcomes regarding project value. The UK-French Hinkley Point C Nuclear Power Station provides the case study. Value is traditionally assessed as inputs and outputs. Here, value is conceptualized as a co-created value proposition at the front-end with implications for realization post-completion. Service-dominant logic (SDL) provides the theoretical lens and contributes to a methodological approach for examining projects. Decision-making outcomes provide the evidence from a range of data sources, including reports and commentaries. The methods are interpretative. The findings show that decision-making extends beyond the time-cost-quality/scope dimensions. The long-term issues regarding value realized are often overlooked. Stakeholders and individual actors have mainly focused upon managing political and financial risks, especially time and cost. The research poses challenges to project management analysis, SDL and research design in assessing evidence. Addressing these issues facilitates a knowledge contribution to SDL theorization and the field of project management. 相似文献
6.
In this paper, the design of all two-input logic gates is presented by only a single-stage single electron box (SEB) for the first time. All gates are constructed based on a same circuit. We have used unique periodic characteristics of SEB to design these gates and present all two-input logic gates (monotonic/non-monotonic, symmetric/non-symmetric) by a single-stage design. In conventional monotonic devices, such as MOSFETs, implementing non-monotonic logic gates such as XOR and XNOR is impossible by only a single-stage design, and a multistage design is required which leads to more complexity, higher power consumption and less speed of the gates. We present qualitative design at first and then detailed designs are investigated and optimised by using our previous works. All designs are verified by a single electron simulator which shows correct operation of the gates. 相似文献
7.
ABSTRACTMultiple-material products are characterised by a complex property profile which is achieved by combining the particular advantages of at least two different materials. Bimetal casting is an energy- and material-efficient technology for the production of multi-metallic objects. This paper describes the development of a semi-continuous casting process for the formation of a rotationally symmetric bimetal with a cohesive bonding character at the interface of a copper–tin alloy (CuSn6) and pure copper (Cu99.5). Initial experiments are conducted by static casting to evaluate the thermal process window. Based on the results of the initial experiments, a vertical semi-continuous compound casting process is developed. A stable cohesive bond between the joining partners is accomplished by forming a solid solution at the interface.This paper is part of a Thematic Issue on Copper and its Alloys. 相似文献
8.
某出口型号交流电力机车牵引控制系统要求变流器控制逻辑具备接触器控制、牵引系统数据交互、变流器故障保护、变流器启动自检等功能。针对以上功能,基于MATLAB中的Simulink/Stateflow可视化编程工具进行牵引控制模型的搭建,遵循模块化编程理念,采用较少的程序代码编写实现复杂的逻辑控制模型,生成逻辑清晰的控制功能流程图,进行半实物仿真测试,增强控制模型的可靠性。通过该变流器产品型式试验检验,验证变流器控制逻辑的功能可以满足控制系统的需求。 相似文献
9.
In this paper, a robust controller for a Six Degrees of Freedom (6 DOF) coaxial octorotor helicopter control is proposed in presence of actuator faults. Radial Base Function Neural Network (RBFNN), Fuzzy Logic Control approach (FLC) and Sliding Mode Control (SMC) technique are used to design a controller, named Fault Tolerant Control (FTC), for each subsystem of the octorotor helicopter. The proposed FTC scheme allows avoiding difficult modeling, attenuating the chattering effect of the SMC, reducing the rules number of the fuzzy controller, and guaranteeing the stability and the robustness of the system. The simulation results show that the proposed FTC can greatly alleviate the chattering effect, good tracking in presence of actuator faults. 相似文献
10.
针对深度神经网络AI研究的可解释性瓶颈,指出刚性逻辑(数理形式逻辑)和二值神经元等价,二值神经网络可转换成逻辑表达式,有强可解释性。深度神经网络一味增加中间层数来拟合大数据,没有适时通过抽象把最小粒度的数据(原子)变成粒度较大的知识(分子),再把较小粒度的知识变成较大粒度的知识,把原有的强可解释性淹没在中间层次的汪洋大海中。要支持多粒度的知识处理,需把刚性逻辑扩张为柔性命题逻辑(命题级数理辩证逻辑),把二值神经元扩张为柔性神经元,才能保持强可解释性。本文详细介绍了从刚性逻辑到柔性逻辑的扩张过程和成果,最后介绍了它们在AI研究中的应用,这是重新找回AI研究强可解释性的最佳途径。 相似文献