A probabilistic load shedding concept considering highly volatile local generation

Automatic load shedding is the ultimate countermeasure against imbalance in a power system and can effectively help preventing large blackouts. Taking into account a high penetration of renewable energy sources (RES) in the distribution grid, a clear distinction between load and generation at the PCC becomes increasingly more difficult. For that reason an adaptation of frequency relay parameters and their locations of installation are necessary. In Europe this is rest on a multi-step plan based on values such as the yearly peak load. In this paper a novel probabilistic method for automatic load shedding is presented that uses the average values instead of peak values for load shedding. Its applicability is verified by a dynamic power system model that was developed to compare the classical and novel probabilistic load shedding principle. The method is verified using data from a German TSO.     

Development and monitoring of an integrated bioprocess for production of a potential malaria vaccine with Pichia pastoris

An engineered variant of the yeast Pichia pastoris was used to produce the potential malaria vaccine D1M1. This paper describes the implementation of an expanded bed adsorption chromatography step into a sequential cultivation process of the yeast in order to link protein expression, cell release, and product capture of the secreted protein in a fully automated plant. The process is operated with a semi-continuous strategy for an integrated production. Process improvements have been achieved using design of experiments. Resulting purities of product achieved up to 87% with recoveries of 51% in a single downstream operation. Furthermore, a multivariate analysis of historical batch data was used to develop a golden batch model for process monitoring.     

嵌入式盲文单手输入系统设计与实现

计算机录入编辑盲文是信息处理的特殊应用领域，是特殊教育中的重要研究课题。文中将盲文制作为特殊符号，通过制作字库，编写个性化码表，然后嵌入到主流输入法，从而实现盲文与汉字混排以及实现单手盲文输入。该系统具有易学易记性、盲文编码多样性、嵌入性强等优点，并通过实验证明输入盲文效率能提高5~6倍，在盲文出版、盲文印刷、盲文教学等领域有重要的应用价值。但盲文字符在不同平台(如智能手机)与不同操作系统兼容性问题还有待进一步研究开发。     

Optimal filtering and control for wireless networked closed-loop control systems

This article studies the optimal filtering and control for wireless networked control systems (WNCSs). In WNCSs, packets may be lost in both control and feedback channels and user datagram protocol is usually used to improve the performance of the real-time control. Relevant literature indicates that the conventional optimal filtering for such a system cannot be applied in practice due to the complex calculation with Gaussian mixtures. This paper proposes a novel scheme to realize the optimal filtering and the linear quadratic Gaussian control for WNCSs, in which the controlled node performs a local estimation and the remote-control node performs the final estimation and control, and a synchronization of two estimators is guaranteed by a communication mechanism. An optimal filtering algorithm is developed, the stability condition of the filtering error covariance is obtained, optimal finite-horizon and infinite-horizon control are derived, and the stability of the closed-loop control system is proved. Numerical simulations show the validity and feasibility of the theoretical results.     

Invader amphipods Gmelinoides fasciatus (Stebbing, 1899) inhabiting distant waterbodies demonstrate differences in tolerance and energy metabolism under elevated temperatures

Gmelinoides fasciatus is a successful invasive amphipod (Amphipoda, Crustacea) that dispersed from Lake Baikal to various waterbodies. Here we studied whether Baikal conditions are optimal for G. fasciatus in terms of thermotolerance and investigated lethal temperatures, 70 kDa heat shock protein level, energy metabolism, and antioxidant defense of animals from three geographically distant waterbodies under changing temperatures. We used acute heat exposure to 28 °C to assess the median lethal times and gradual temperature increase from 6 °C to determine the lethal temperatures. Mortality under heat shock was explainable by the baseline content of Hsp70 that correlated with thermal history. But it was not the case under gradual temperature increase where Hsp70 levels became similar and the mortality pattern changed. The most thermotolerant amphipods from the Gulf of Finland demonstrated a higher amount of free glucose during the temperature increase that may be related to the higher salinity of this waterbody and less energy required for ion regulation. Even though concentrations of major physiological ions in Lake Baikal are lower than in Lake Ladoga, G. fasciatus from Ladoga was slightly more sensitive to the gradual temperature increase. This difference could be explained by the influence of high levels of humic and other potentially toxic substances in Lake Ladoga indicated by increased activities of catalase and glutathione S-transferase. Importantly, all G. fasciatus populations accumulated relatively low levels of lactate during the temperature increase, which may reflect the ability of this invasive species to effectively maintain aerobic metabolism under various conditions.     

郭庄煤业选煤厂振动筛筛选形式的优化研究

针对郭庄煤业选煤厂振动筛振动筛分方式可靠性差、筛分效率低下、物料筛分率低的难题,本文提出了三种新的振动筛分方案,对不同筛分方案的实际应用效果进行了分析。结果表明三移动一摆动的振动筛分方式对物料的综合分散度最高,稳定性好,该筛分方案已在郭庄煤业选煤厂煤炭筛分过程中得到了全面的应用。     

Studying the effect of organo-modified nanoclay loading on the thermal stability,flame retardant,anti-corrosive and mechanical properties of polyurethane nanocomposite for surface coating

Clay polyurethane nanocomposite (CPN) coating films were fabricated by uniformly dispersing nanoclay, organically modified with 25–30 wt.% octadecylamine in varying concentrations up to 5 wt.%, in a commercial two component, glossy, acrylic aliphatic polyurethane using ultrasonication. Organo-modified nanoclay was characterized by X-ray diffraction (XRD). The dispersion of the nanoclay into the matrix was investigated by scanning electron microscopy (SEM). CPN coating films were characterized by thermogravimetric analysis (TGA), and flame retardant, corrosion resistance and mechanical properties were also investigated. The XRD measurement indicated that, the organo-modified nanoclay particles were mainly constituted of montmorillonite with traces of quartz and calcite also found to be present. The SEM analysis showed that the nanoclay layers were dispersed and intercalated into the polyurethane coating. Thermogravimetric analysis showed that incorporating 5 wt.% organo-nanoclay into polyurethane considerably enhanced the thermal stability and increased the char residue to 14.11 wt.% relative to 4.58 for the sample without organo-nanoclay (blank polyurethane). The limiting oxygen index (LOI) test revealed that incorporation of organo-nanoclay led to a further increase in LOI values, which indicate an improvement in flame retardancy properties. The corrosion resistance also improved and this improvement increases with increase nanoclay wt.%. The mechanical resistance measurements demonstrated that the gloss of the CPN coating films slightly decreased, although hardness, adhesion and impact resistance of the CPN coating films improved with the incorporation of the organo-nanoclay.     

Sleep Disorders Reduce Health-Related Quality of Life in Multiple Sclerosis (Nottingham Health Profile Data in Patients with Multiple Sclerosis)

Quality of Life (QoL) is decreased in multiple sclerosis (MS), but studies about the impact of sleep disorders (SD) on health-related quality of Life (HRQoL) are lacking. From our original cohort, a cross-sectional polysomnographic (PSG) study in consecutive MS patients, we retrospectively analysed the previously unpublished data of the Nottingham Health Profile (NHP). Those MS patients suffering from sleep disorders (n = 49) showed significantly lower HRQoL compared to MS patients without sleep disorders (n = 17). Subsequently, we classified the patients into four subgroups: insomnia (n = 17), restless-legs syndrome, periodic limb movement disorder and SD due to leg pain (n = 24), obstructive sleep apnea (n = 8) and patients without sleep disorder (n = 17). OSA and insomnia patients showed significantly higher NHP values and decreased HRQoL not only for the sleep subscale but also for the “energy” and “emotional” area of the NHP. In addition, OSA patients also showed increased NHP values in the “physical abilities” area. Interestingly, we did not find a correlation between the objective PSG parameters and the subjective sleep items of the NHP. However, this study demonstrates that sleep disorders can reduce HRQoL in MS patients and should be considered as an important confounder in all studies investigating HRQoL in MS.     

Binary Ti–Fe system. Part I: Experimental investigation at high pressure

The present work illustrates the effect of quasi-hydrostatic pressure on the positions and widths of the homogeneity ranges of the intermetallic phases TiFe and TiFe₂ at high temperatures. The experiments were performed with Ti–Fe diffusion couples that were heat treated in a multi-anvil press at 2.5 GPa. The solubility limits of the phases were derived from the concentration profiles that were measured using electron probe microanalysis. It was found that the homogeneity ranges of TiFe and TiFe₂ extend to higher titanium concentrations, if the pressure is applied. The positions of the phase boundaries of the intermetallics on the iron-rich side are not affected by the pressure. The accuracy of the experimental data including the homogeneity ranges and temperatures was verified by comparing the homogeneity ranges of β-Ti(Fe), α/δ-Fe(Ti) and γ-Fe measured in this study with the homogeneity ranges taken from literature. The pressure was calibrated using the pressure-induced phase transitions of bismuth.