Form Of Envelopes Research Articles

Risk-aware scheduling and dispatch of flexibility events in buildings

Residential and commercial buildings, equipped with systems such as heat pumps (HPs), hot water tanks, or stationary energy storage, have a large potential to offer their consumption flexibility as grid services. In this work, we leverage this flexibility to react to consumption requests related to maximizing self-consumption and reducing peak loads. We employ a data-driven virtual storage modeling approach for flexibility prediction in the form of flexibility envelopes for individual buildings. The risk-awareness of this prediction is inherited by the proposed scheduling algorithm. A Mixed-integer Linear Program (MILP) is formulated to schedule the activation of a pool of buildings in order to best respond to an external aggregated consumption request. This aggregated request is then dispatched to the active individual buildings, based on the previously determined schedule. The effectiveness of the approach is demonstrated by coordinating up to 500 simulated buildings using the Energym Python library and observing about 1.5 times peak power reduction in comparison with a baseline approach while maintaining comfort more robustly. We demonstrate the scalability of the approach by solving problems with 2000 buildings in about 21 s, with solving times being approximately linear in the number of considered assets.

Ergonomics Simulation and Analysis of Specially Designed Chair

Chair comes in different sizes and shapes depending on the functions as well as the users involved. However, the designers seldom consider the ergonomics aspect in chair design. This research has been conducted as a case study to compare and select the best design parameters within two chairs known as Chair A and B using human modelling software called AnyBody. Different parameter was manipulated in the simulation which is backrest angles for Chair A and seat heights for Chair B. A total of ten chairs with different parameters (five from Chair A and five from Chair B) were conducted in the simulation. Results were generated through inverse dynamics analysis in the form of muscle activities envelopes and reaction force on vertebrae L4 to L5. The result shows that 80° backrest was the best ergonomics design for Chair A while 0.30 m seat height was the best ergonomics design for Chair B. The simulation conducted is important as an early ergonomics intervention before the real chair fabrication is conducted.

Impact of the Geometric Form of the Building Envelopes on The efficiency of Natural Lighting in the Office Space.

Envelopes play an important role in Office Buildings.They affect visual comfort for the user Driven by architectural trends and the need to maximize natural light In order to realize required visual comfort conditions. advanced glazing systems, Geometric formation of the outer building envelope proper self- shading properties and control and lighting controls should be studied comprehensively Optimized fenestration system design may improve exploitation of daylight. and it can be controlled to harvest maximum daylight thus reaching the maximum depth naturally illuminated. The paper explains the design relationship between both configuration of office space and between the system of the glazing and the transmission of natural light inside the space, in terms of the design characteristics of the office space (proportions, dimensions), in order to achieve visual comfort to improve the efficiency of the environmental performance of Office Buildings. This paper discusses the study of the environmental effects of the glazing façades of office buildings and their impact on the efficiency of natural lighting and visual comfort. The paper relies on simulation using, the Grasshopper program, in analyzing of the building’s Envelopes and its external elements and the architectural space, in order to find the proper form for improving visual performance.

Deriving RNA topological structure from SAXS.

Structures of well-folded RNA molecules can be determined with atomic resolution by either X-ray crystallography, cryo-EM, or NMR spectroscopy, but those of conformationally-flexible RNAs often are difficult to study with these methods. However, flexible RNAs have biological relevance and likely represent the majority of the RNA conformational space. Due to the high electron density of the phosphate-sugar backbone, RNA is very sensitive to small-angle X-ray scattering (SAXS), and SAXS data can be recorded with sub-μM concentrations and under near-physiological solution conditions without the need for labeling. For these reasons, SAXS has significant advantages over other techniques for obtaining global structural information of flexible RNAs in the form of molecular envelopes or low-resolution topological structural models. The SAXS-derived information is extremely valuable for bridging secondary structure data, often determined by other techniques, with a three-dimensional structure description. In this chapter, we present a detailed account of the principle, algorithms, and experimental and computational protocols for topological structure determination of RNA molecules in solution. To illustrate the applications of the methodology, we provide several case studies that cover a broad spectrum of the RNA conformational landscape.

Ergonomics Simulation and Analysis of Specially Designed Chair

Chair comes in different sizes and shapes depending on the functions as well as the users involved. However, the designers seldom consider the ergonomics aspect in chair design. This research has been conducted as a case study to compare and select the best design parameters within two chairs known as Chair A and B using human modelling software called AnyBody. Different parameter was manipulated in the simulation which is backrest angles for Chair A and seat heights for Chair B. A total of ten chairs with different parameters (five from Chair A and five from Chair B) were conducted in the simulation. Results were generated through inverse dynamics analysis in the form of muscle activities envelopes and reaction force on vertebrae L4 to L5. The result shows that 80° backrest was the best ergonomics design for Chair A while 0.30 m seat height was the best ergonomics design for Chair B. The simulation conducted is important as an early ergonomics intervention before the real chair fabrication is conducted.

The impact of coppice management on spatial structure and intraspecific interactions of Brant's oak (Quercus brantii Lindl.) semi-arid woodlands

Coppicing is a common management strategy in oak woodlands; however, our knowledge is limited in the impacts of coppicing on spatial structure and growth dynamics of oak stands. In this study, we compared the spatial patterns of two adjacent high and coppice pure stands of Brant's oak (Quercus brantii Lindl.) in central part of Zagros semi-arid woodlands, western Iran. We used univariate form of scale-dependent summary statistics (nearest neighbour distribution function, L-function, pair- and mark correlation functions) and Analytical Global Envelopes under inhomogeneous Poisson process which allow detection of the intraspecific interactions of the individuals within the high and coppice stands. Our results indicated the aggregation of oak individuals at small spatial scales (i.e., 0-3 m) in the high stand, most likely as a result of aggregation in parts with environmentally benign conditions. The positive interactions of conspecifics had a marked effect on their size (e.g., larger height (5%), DBH (24%), and crown area (50%) than mean size at spatial scale of 2 m) inferred as growth stimulation and aggregation of young trees around their nurse or parent trees. However, the findings revealed the segregation of oak trees at short distances in the coppice stand (i.e., 0–5 m), probably due to strong competition of conspecific neighbors. The negative size correlation of oaks (e.g., smaller height, DRC, and crown area of oak individuals (15%) than mean size at distance of 2 m) was considered as the outcome of competition for scarce resources in the woodlands with unfavourable conditions. In general, it was concluded that the aggregated spatial structure of the high stand has changed to segregation of individuals within the coppice stand. Additionally, we found that environmental heterogeneity and intraspecific competition are the main drivers of the high and coppice stands, respectively.

Biodiversity in the Black Sea - ecological Study from the Perspective of Romanian philately

As the concern for the management of protected areas is relatively new in Romania, and the information related to this topic is relatively scarce, especially those on marine ecosystems, we considered necessary this study on the management of marine protected areas with specific biodiversity illustrated by philately. Marine protected areas, in particular, delimited as areas where the main purpose is the protection of nature and cultural values, are important for all segments of society. Through this paper, we aimed to review several aspects, ecological and philatelic alike, regarding the specific biodiversity of the Black Sea ecosystem. Following the analyzes performed on account of the data from the consulted specialized literature (in the form of postage stamps, FDCs, occasional envelopes, and maximum postcards, but also other philatelic effects), as well as as a result of other observations (with catalogs and sites with philatelic content), we concluded that the biodiversity of the Black Sea, as well as the marine ecosystem itself, are relatively well represented in Romanian philately. The four philatelic issues illustrate crustaceans, mollusks, corals, and anemones, but also other species, all being to the liking of the general public in terms of information and promotion.

Conventional Partial and Complete Solutions of the Fundamental Equations of Fluid Mechanics in the Problem of Periodic Internal Waves with Accompanying Ligaments Generation

The problem of generating beams of periodic internal waves in a viscous, exponentially stratified fluid by a band oscillating along an inclined plane is considered by the methods of the theory of singular perturbations in the linear and weakly nonlinear approximations. The complete solution to the linear problem, which satisfies the boundary conditions on the emitting surface, is constructed taking into account the previously proposed classification of flow structural components described by complete solutions of the linearized system of fundamental equations without involving additional force or mass sources. Analyses includes all components satisfying the dispersion relation that are periodic waves and thin accompanying ligaments, the transverse scale of which is determined by the kinematic viscosity and the buoyancy frequency. Ligaments are located both near the emitting surface and in the bulk of the liquid in the form of wave beam envelopes. Calculations show that in a nonlinear description of all components, both waves and ligaments interact directly with each other in all combinations: waves-waves, waves-ligaments, and ligaments-ligaments. Direct interactions of the components that generate new harmonics of internal waves occur despite the differences in their scales. Additionally, the problem of generating internal waves by a rapidly bi-harmonically oscillating vertical band is considered. If the difference in the frequencies of the spectral components of the band movement is less than the buoyancy frequency, the nonlinear interacting ligaments generate periodic waves as well. The estimates made show that the amplitudes of such waves are large enough to be observed under laboratory conditions.

Two-Dimensional Bearing Capacity of a Spudcan in Clay After Penetrating Through Top Sand

This paper presents a series of numerical investigations of the capacity of the foundations of a spudcan in clay after it penetrates through a sand layer and under planar combined loading. The model is validated against available relationships for uniaxial capacity of spudcan foundations on clay soils. The model is then used to investigate the uniaxial capacity and combined VH, VM, and HM capacity of spudcan foundations in the underlying clay of sand overlying clay soils. The results are presented in the form of failure envelopes. The effects of the embedment depth, undrained shear strength of clay, and sand plug thickness on the uniaxial and combined capacity are investigated and discussed.

Numerical study on the lateral breakout behaviour of deep-water pipelines in clays with surficial crust

Formation of thin crust over normally consolidated clay in many deep-water regions had been reported in the literature. In this paper, the effect of crustal formation on the lateral breakout behaviour of shallowly embedded pipelines is captured. A series of finite-element analyses are carried out to investigate the limiting bearing capacity of both rough and smooth pipes under combined loading. The effects of crust thickness, pipe embedment and relative shear strength of underlying soil and crust have been quantified. Results are presented in the form of failure envelopes under combined loading. Simple equations are proposed to estimate the uniaxial and breakout resistances of pipelines embedded in clay with surficial crustal layer.

Beachrock Cementation Patterns Along the Gulf of Aqaba Coast, Saudi Arabia

Beachrocks crop out along the Saudi coast of the Gulf of Aqaba with beds lying at elevations up to 0.8 m above the present sea level and with seaward extents that repeatedly submerge and emerge during high and low water levels. This study discusses the cement composition, petrography and bedding features of beachrocks at 24 different locations, of which a total of eight sites were sampled. The study focuses on the petrographic and microtextural characteristics of the beachrocks to elucidate their cementation environment and diagenetic evolution. The results revealed the predominance of three main cement types: (1) fibrous aragonite cement with morphologies including isopachous rims around grains with or without micritic substrates, pore-filling radial aggregates, pseudospherulite and randomly oriented interlocking aragonite fibers; (2) microcrystalline low-Mg calcite (LMC) cement binding grains and filling inter- and intra-granular pore spaces; and (3) micritic cement in the form of envelopes and/or pore-filling micrite in some samples with meniscus bridges. The last two types also contain infiltrated silt-sized clasts and skeletal remains. The cements indicate precipitation mainly in pore-filled marine phreatic diagenetic zone and, rarely, in the marine vadose zone with the aid of microbial and algal activity. Petrographic investigations and energy-dispersive X-ray spectroscopy of selected samples showed the occurrences of aragonite and LMC.

IRC +10 216 in 3-D: morphology of a TP-AGB star envelope.

During their late pulsating phase, AGB stars expel most of their mass in the form of massive dusty envelopes, an event that largely controls the composition of interstellar matter. The envelopes, however, are distant and opaque to visible and NIR radiation: their structure remains poorly known and the mass-loss process poorly understood. Millimeter-wave interferometry, which combines the advantages of longer wavelength, high angular resolution and very high spectral resolution is the optimal investigative tool for this purpose. Mm waves pass through dust with almost no attenuation. Their spectrum is rich in molecular lines and hosts the fundamental lines of the ubiquitous CO molecule, allowing a tomographic reconstruction of the envelope structure. The circumstellar envelope IRC +10 216 and its central star, the C-rich TP-AGB star closest to the Sun, are the best objects for such an investigation. Two years ago, we reported the first detailed study of the CO(2-1) line emission in that envelope, made with the IRAM 30-m telescope. It revealed a series of dense gas shells, expanding at a uniform radial velocity. The limited resolution of the telescope (HPBW 11″) did not allow us to resolve the shell structure. We now report much higher angular resolution observations of CO(2-1), CO(1-0), CN(2-1) and C4H(24-23) made with the SMA, PdB and ALMA interferometers (with synthesized half-power beamwidths of 3″, 1″ and 0.3″, respectively). Although the envelope appears much more intricate at high resolution than with an 11″ beam, its prevailing structure remains a pattern of thin, nearly concentric shells. The average separation between the brightest CO shells is 16″ in the outer envelope, where it appears remarkably constant. Closer to the star (< 40″), the shell pattern is denser and less regular, showing intermediary arcs. Outside the small (r < 0.3″) dust formation zone, the gas appears to expand radially at a constant velocity, 14.5 km s-1, with small turbulent motions. Based on that property, we have reconstructed the 3-D structure of the outer envelope and have derived the gas temperature and density radial profiles in the inner (r < 25″) envelope. The shell-intershell density contrast is found to be typically 3. The over-dense shells have spherical or slightly oblate shapes and typically extend over a few steradians, implying isotropic mass loss. The regular spacing of shells in the outer envelope supports the model of a binary star system with a period of 700 years and a near face-on elliptical orbit. The companion fly-by triggers enhanced episodes of mass loss near periastron. The densification of the shell pattern observed in the central part of the envelope suggests a more complex scenario for the last few thousand years.

Predicted microbial secretomes and their target substrates in marine sediment.

Scientific drilling has identified a biosphere in marine sediments 1 , which contain many uncultivated microbial groups known only by their DNA sequences 2-4 . Recycling of organic matter in sediments is an important component of biogeochemical cycles because marine sediments are critical forlong-term carbon storage 5 . Turnover of carbon is hypothesized to be driven by the secretion of enzymes by microbial organisms 5-7 , which act to break down macromolecules into constitutive monomers that can be transported into cells. As such, the nature of the microbial secretome often influences the function of a community 6 . However, the microbial groups involved in this process and the biochemistry theyencode is poorly understood. Here, we show that expressed genes from 5 to 159 meters below the seafloor 8 (mbsf) encode numerous candidate peptidases and carbohydrate-active enzymes ('CAZymes') 9 targeted for secretion. The majority (90-99%) were assigned to Bacteria, of which 12% shared the highest sequence similarity with candidate phyla 10,11 . The remaining putatively secreted proteins shared highest sequence similarity with archaeal and fungal enzymes, which peak in two redox transition zones 12 . In the shallower redox zone at 30 mbsf, 20% of the transcripts encoding putative secreted peptidases were assigned to lineages 7,13,14 of uncultivated Archaea. The target compounds of the predicted secreted proteome show a preference for necromass in the form of microbial cell envelopes as well as plankton and algal detritus. The predicted fungal secreted proteome encodes CAZymes not present in the predicted bacterial or archaeal secreted proteomes, indicating that fungi putatively play a minimal but specialized role in subseafloor carbohydrate recycling.

A new yield and failure theory for composite materials under static and dynamic loading

To facilitate and accelerate the process of introducing, evaluating and adopting new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of composite structures based on the properties of the constituent materials, e.g., fibers, matrix, and the single ply or lamina. A new yield/failure theory is proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is based on the equivalent stress concept derived from energy principles and is expressed in terms of a single criterion. It is presented in the form of master yield and failure envelopes incorporating strain rate effects. The theory can be further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive damage of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without extensive testing and offers easily implemented design tools.

Undrained capacity of a surface circular foundation under fully three-dimensional loading

Circular foundations are widely employed in offshore engineering to support facilities and are generally subjected to fully three-dimensional loading due to the harsh offshore environmental load and complex operational loads. The undrained capacity of surface circular foundations on soil with varying strength profiles and under fully three-dimensional loading is investigated and presented in the form of failure envelopes that obtained from finite element analyses. The combined ultimate limit state of circular foundations is defined as the two-dimensional failure envelopes in resultant H-M loading space accounting for the vertical load and torsion mobilisation. The effects of vertical load and torsion mobilisation, soil shear strength heterogeneity and loading angle from moment to horizontal load on the shape of normalised H-M failure envelopes are explored. A series of expressions are proposed to describe the shape of failure envelopes obtained numerically, enabling essentially instantaneous generation of failure envelopes and optimisation of a circular foundation design based on constraint of any input variable through implementation in an automated calculation tool. An example application is ultimately provided to illustrate how the proposed expressions may be used in practice.

Bearing capacity of strip footings on two-layered clay under combined loading

In this paper, a lower bound limit analysis in conjunction with finite elements and second-order cone programming (SOCP) is used to determine the bearing capacity of a rigid strip footing placed on two-layered clay subjected to inclined or eccentric loading. The footing is founded on the free surface of the soil mass with no surcharge applied. Two types of footing–soil interfaces are considered: (1) zero tensile capacity and (2) non-zero tensile capacity. The numerical results are presented in the form of failure envelopes in the loading plane, and the corresponding failure mechanisms are also presented. The size and shape of the failure envelopes are dependent on (1) the undrained shear strength ratio (cu1/cu2), where cu1 and cu2 are the undrained shear strength of the top and bottom clay, respectively, and (2) the normalized thickness D/B of the upper clay, where D is the thickness of the top clay layer and B is the width of the footing.

Temporal Planning With Required Concurrency Using Classical Planning

In this paper we describe two novel algorithms for temporal planning. The first algorithm, TP, is an adaptation of the TEMPO algorithm. It compiles each temporal action into two classical actions, corresponding to the start and end of the temporal action, but handles the temporal constraints on actions through a modification of the Fast Downward planning system. The second algorithm, TPSHE, is a pure compilation from temporal to classical planning for the case in which required concurrency only appears in the form of single hard envelopes. We describe novel classes of temporal planning instances for which TPSHE is provably sound and complete. Compiling a temporal instance into a classical one gives a lot of freedom in terms of the planner or heuristic used to solve the instance. In experiments TPSHE significantly outperforms all planners from the temporal track of the International Planning Competition.

Ultimate Elastic Wall Stress (UEWS) Test under Biaxial Loading for Glass-Fibre Reinforced Epoxy (GRE) Pipes

This paper presents the results of an experimental investigation into the Ultimate Elastic Wall Stress (UEWS) of ±55° filament wound composite pipes. The UEWS test appears to provide an attractive alternative to the current method, and has proved to be one of the most effective in term of accuracy and speed. Moreover, it has been found to be sensitive to changes in key manufacturing and raw material parameters. The pipes were subjected to biaxial loading, which was achieved by combinations of hoop and axial stress. Loads were applied as groups of cycles which, were gradually increased until the UEWS had been determined. Various ratios of hoop to axial stress were applied to the pipes, ranging from pure axial to pure hoop loading at room temperature and at 65°C. These ratios were investigated by applying different pressures in both the main and small chambers built inside the pipe, and therefore it was unnecessary to add any external loads to the pipe wall. Tests were also conducted to observe leakage through the pipe wall. The main failure mode observed was weepage through the pipe wall, which was due to intensive matrix microcracking. The results from the UEWS tests are presented in the form of failure envelopes showing the effects of testing at an elevated temperature. Finally, degradation in the elastic properties of the pipe wall is also discussed and plotted against wall stress.

A technique to derive the analytical form of convex envelopes for some bivariate functions

In the recent paper (Locatelli and Schoen in Math Program, 2013) it is shown that the value of the convex envelope of some bivariate functions over polytopes can be computed by solving a continuously differentiable convex problem. In this paper we show how this result can be exploited to derive in some cases the analytical form of the envelope. The technique is illustrated through two examples.

Localized whistlers in magnetized spin quantum plasmas

The nonlinear propagation of electromagnetic (EM) electron-cyclotron waves (whistlers) along an external magnetic field, and their modulation by electrostatic small but finite amplitude ion-acoustic density perturbations are investigated in a uniform quantum plasma with intrinsic spin of electrons. The effects of the quantum force associated with the Bohm potential and the combined effects of the classical as well as the spin-induced ponderomotive forces (CPF and SPF, respectively) are taken into consideration. The latter modify the local plasma density in a self-consistent manner. The coupled modes of wave propagation is shown to be governed by a modified set of nonlinear Schrödinger-Boussinesq-like equations which admit exact solutions in form of stationary localized envelopes. Numerical simulation reveals the existence of large-scale density fluctuations that are self-consistently created by the localized whistlers in a strongly magnetized high density plasma. The conditions for the modulational instability (MI) and the value of its growth rate are obtained. Possible applications of our results, e.g., in strongly magnetized dense plasmas and in the next generation laser-solid density plasma interaction experiments are discussed.