Saturated steam process with direct steam generating parabolic troughs

The direct steam generation (DSG) in parabolic trough collectors is an attractive option regarding the economic improvement of parabolic trough technology for solar thermal electricity generation in the multi Megawatt range. The European DISS project has proven the feasibility of the direct steam generation under real solar conditions in more than 4000 operation hours. Within the European R&D project INDITEP the detailed engineering for a pre-commercial DSG solar thermal power plant with an electrical power of 5 MW is being performed. This small capacity was chosen to minimise the risk for potential investors.In regards to DSG solar thermal power plants, only steam cycles using superheated steam have been investigated so far. The paper will investigate the advantages, disadvantages, and design considerations of a steam cycle operated with saturated steam for the first time. For near term applications, saturated steam operated DSG plants might be an interesting alternative for power generation in the small capacity range due to some specific advantages:

• Simple set up of the collector field.

• Proven safe collector field operation.

• Higher thermal efficiency in the collector field.

Seiltausch unter Verkehr an der Rheinbrücke Flehe

Es wird über den Seiltausch an der Rheinbrücke Flehe berichtet. Auf Grund umfangreicher Schäden an der Seilabspannung mussten neun Tragseile der Rheinbrücke Flehe im Zuge der Bundesautobahn A46 getauscht werden. Wegen der sehr hohen täglichen Verkehrsbelastung waren Eingriffe in den laufenden Verkehr weitgehend zu verhindern, so dass der Seiltausch bei laufendem Verkehr durchgeführt wurde. Diese komplexe Aufgabe stellte höchste Anforderungen an alle Beteiligten, wurde aber letztlich mit einem erfolgreichen Abschluss der Maßnahme belohnt. Replacing stay‐cables of the Rhine River crossing Rheinbrücke Flehe, Germany. The paper reports on the replacement works of nine stay cables of the Rhine River Bridge Flehe, a cable‐stayed bridge south of Düsseldorf, Germany. Due to a long service life the stay cables showed some signs of damage and needed to be repaired. Because of foremost damages of nine cables especially open fractures of single wires, they had to be replaced instead. The replacement not only required enormous structural and technical skills, but also engagement of all involved in. This was mainly due to the necessity of keeping the traffic uninterrupted and to prevent any closures of lanes. This administrational demand was successfully mastered. Besides slightly narrowed lanes widths, the bridge's traffic area remained unaffected by this replacement work with traffic able to continue flowing throughout the project.     

Observer effect from stateful resources in agent sensing

In many real-world applications of multi-agent systems, agent reasoning suffers from bounded rationality caused by both limited resources and limited knowledge. When agent sensing to overcome its knowledge limitations also requires resource use, the agent’s knowledge refinement is affected due to its inability to always sense when and as accurately as needed, further leading to poor decision making. In this paper, we consider what happens when sensing actions require the use of stateful resources, which we define as resources whose state-dependent behavior changes over time based on usage. Current literature addressing agent sensing with limited resources primarily investigates stateless resources, such as avoiding the use of too much time or energy during sensing. However, sensing itself can change the state of a resource, and thus its behavior, which affects both the information gathered and the resulting knowledge refinement. This produces a phenomenon where the sensing action can and will distort its own outcome (and potentially future outcomes), termed the Observer Effect (OE) after the similar phenomenon in the physical sciences. Under this effect, when deliberating about when and how to perform sensing that requires use of stateful resources, an agent faces a strategic tradeoff between satisfying the need for (1) knowledge refinement to support its reasoning, and (2) avoiding knowledge corruption due to distorted sensing outcomes. To address this tradeoff, we model sensing action selection as a partially observable Markov decision process where an agent optimizes knowledge refinement while considering the (possibly hidden) state of the resources used during sensing. In this model, the agent uses reinforcement learning to learn a controller for action selection, as well as how to predict expected knowledge refinement based on resource use during sensing. Our approach is unique from other bounded rationality and sensing research as we consider how to make decisions about sensing with stateful resources that produce side effects such as the OE, as opposed to simply using stateless resources with no such side effect. We evaluate our approach in a fully and partially observable agent mining simulation. The results demonstrate that considering resource state and the OE during sensing action selection through our approach (1) yielded better knowledge refinement, (2) appropriately balanced current and future refinement to avoid knowledge corruption, and (3) exploited the relationship (i.e., high, positive correlation) between sensing and task performance to boost task performance through improved sensing. Further, our methodology also achieved good knowledge refinement even when the OE is not present, indicating that it can improve sensing performance in a wide variety of environments. Finally, our results also provide insights into the types and configurations of learning algorithms useful for learning within our methodology.     

BTF-CIELab: A Perceptual Difference Measure for Quality Assessment and Compression of BTFs

Driven by the advances in lossy compression of bidirectional texture functions (BTFs), there is a growing need for reliable methods to numerically measure the visual quality of the various compressed representations. Based on the CIE    Δ E ₀₀    colour difference equation and concepts of its spatio-temporal extension ST-CIELab for video quality assessment, this paper presents a numerical quality measure for compressed BTF representations. By analysing the BTF in its full six-dimensional (6D) space, light and view transition effects are integrated into the measure. In addition to the compressed representation, the method only requires the source BTF images as input and thus aids the objective evaluation of different compression techniques by means of a simple numerical comparison. By separating the spatial and angular components of the difference measure and linearizing each of them, the measure can be incorporated into any linear or multi-linear compression technique. Using a per-colour-channel principal component analysis (PCA), compression rates of about 500:1 can be achieved at excellent visual quality.     

Design Families and Design Individuals

This paper discusses design families and design individuals. Phase space is introduced to complement state space. Phase transition as a generic method of generating design families is proposed and then demonstrated through an example of simple designs with one component. Based on phase transition in the biological world, a development model for complex designs (with multi-components) is established, by which different phase transitions for changing complex design families are analysed and simulated. Two concepts are drawn from the biological analogy: through gene mutation and regulation the individuals of complex design systems can be varied and searched within their state space; and by changing the interpretation process of genes, the families of such systems can be explored within their phase space.     

Photo-realistic Rendering of Metallic Car Paint from Image-Based Measurements

State‐of‐the‐art car paint shows not only interesting and subtle angular dependency but also significant spatial variation. Especially in sunlight these variations remain visible even for distances up to a few meters and give the coating a strong impression of depth which cannot be reproduced by a single BRDF model and the kind of procedural noise textures typically used. Instead of explicitly modeling the responsible effect particles we propose to use image‐based reflectance measurements of real paint samples and represent their spatial varying part by Bidirectional Texture Functions (BTF). We use classical BRDF models like Cook‐Torrance to represent the reflection behavior of the base paint and the highly specular finish and demonstrate how the parameters of these models can be derived from the BTF measurements. For rendering, the image‐based spatially varying part is compressed and efficiently synthesized. This paper introduces the first hybrid analytical and image‐based representation for car paint and enables the photo‐realistic rendering of all significant effects of highly complex coatings.     

Differential Expression of PD-L1 during Cell Cycle Progression of Head and Neck Squamous Cell Carcinoma

The expression of PD-L1 by tumor cells is mainly associated with its immunosuppressive effect. In fact, PD-1/PD-L1 immune checkpoint inhibitors demonstrated remarkable effects in advanced cancer patients including HNSCC. In this context, irradiation is currently being investigated as a synergistic treatment modality to immunotherapy. However, the majority of HNSCC patients still show little improvement or even hyperprogression. Interestingly, there is increasing evidence for additional cell-intrinsic functions of PD-L1 in tumor cells. In previous studies, we showed that PD-L1 has a strong influence on proliferation, migration, invasion, and survival after irradiation. We demonstrated that cellular expression and localization of PD-L1 differed depending on sensitivity to irradiation. Here, we show that PD-L1 is also differentially expressed during cell cycle progression of HNSCC. Furthermore, cellular localization of PD-L1 also changes depending on a particular cell cycle phase. Moreover, distinct observations occurred depending on the general differentiation status. Overall, the function of PD-L1 cannot be generalized. Rather, it depends on the differentiation status and microenvironment. PD-L1 expression and localization are variable, depending on different factors. These findings may provide insight into why differential response to PD-1/PD-L1 antibody therapy can occur. Detailed understanding of cell-intrinsic PD-L1 functions will further allow antibody-based immunotherapy to be optimized.     

Enduring principles of architecture in Alberti's On the Art of Building': how did Alberti set out to formulate them?

Leon Battista Alberti was not only the author of the first Renaissance treatises on painting, sculpture, and architecture. He was also the first to succeed in writing a systematic account of the principles of building considered as an art, essential for the well-being and preservation of the state and its citizens, and worthy of the interest of wealthy patrons and erudite humanists. In this paper I argue that Alberti succeeded in doing so not because, as is generally assumed, he set out towrite a treatise about the principles of classical architecture based on Vitruvius, but because he presented an analysis of architecture based on an a-historical and a-stylistic conceptual framework, in which Nature instead of the ancients was the ultimate authority. Although he did not consider architecture to be a language, this framework did enable him to use the methodological and structural models offered by classical treatises on rhetoric to construct his own systematic treatment of architecture considered as an art. (This article was held over from the Spring issue, which contained material from a conference on the theme 'Are there evolving principles in architecture?')     

Effect of Solvent,Preheating Temperature,and Time on the Ultrasonic Extraction of Phenolic Compounds from Cold‐Pressed Hempseed Cake

The effect of different solvents (aqueous methanol [70%, v/v], aqueous acetone [80%, v/v], and a solvent mixture [MA] of aqueous methanol [70%, v/v] and aqueous acetone [70%, v/v] in a ratio of 1:1 [v/v]), preheating temperatures (140, 160, and 180°C), and times of exposure (5, 15, and 30 min) on the ultrasonic extraction of the main phenolic compounds from hempseed cake (Cannabis sativa) was investigated. A simplified new high‐performance liquid chromatography (HPLC) method was developed to identify and quantify the main phenolics (namely, N‐trans‐caffeoyltyramine and cannabisin B) in the extracts. Two other main compounds, numbered 3 and 4 , were also detected. The results showed that the nature of the extracting solvent had a significant (P < 0.05) impact on the ultrasonic extraction of phenolic compounds. The acetone extracts exhibited the highest total phenolic content (TPC), followed by MA and methanol. The preheating temperature and time of exposure enhanced the TPC for all solvents examined. The main phenolics, N‐trans‐caffeoyltyramine, cannabisin B, and compound 3 , were positively affected by the temperature and time of exposure, irrespective of the solvents used. In sharp contrast, compound 4 appeared to be thermally sensitive: increasing preheating time and temperature decreased the yields of this compound. This study demonstrated that acetone was the most effective extracting solvent and that preheating enhanced the yield of the main phenolics.