Compact Block Research Articles

Compact block boundary value methods for semi‐linear delay‐reaction–diffusion equations with algebraic constraints

AbstractIn the present paper, we study a class of linear approximation methods for solving semi‐linear delay‐reaction–diffusion equations with algebraic constraint (SDEACs). By combining a fourth‐order compact difference scheme with block boundary value methods (BBVMs), a class of compact block boundary value methods (CBBVMs) for SDEACs are suggested. It is proved under some suitable conditions that the CBBVMs are convergent of order 4 in space and order p in time, where p is the local order of the used BBVMs, and are globally stable. With several numerical experiments for Fisher equation with delay and algebraic constraint, the computational effectiveness and theoretical results of CBBVMs are further illustrated.

Purification and structural characterization and antioxidant activity of levan from Bacillus megaterium PFY-147

An exopolysaccharide (EPS)-producing bacterial PFY-147 was separated from Hiqiher vineyard soil and determined as Bacillus megaterium by 16S rDNA analysis and morphological. The PFY-147-EPS was purified by gel-filtration chromatography. The average molecular weight (Mw) of purified EPS was 1.878 × 106 Da. The total carbohydrate contents, uronic acid and sulfated group content in PFY-147-EPS were found to be 90.37 ± 1.48%, 7.24 ± 0.36% and 2.39 ± 0.36%, respectively. The PFY-147-EPS was found to be a levan containing a backbone of 2,6-substituted β-fructoses by high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) and Fourier transform infrared (FT-IR) spectroscopy. The atomic force microscopy (AFM) presented that the levan formed pointed or thorny structural in aqueous solution. Scanning electron microscopy (SEM) of the levan showed compact and nonuniform block sizes morphology. Moreover, the levan exhibited higher thermal stability with a degradation temperature of 265.63 °C in DSC analysis. The levan possessed strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, Superoxide anion (O2−) radical, hydroxyl (OH) radical and and2,20-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS+) scavenging activities and strong metal ion chelating activity. The WHC and WSI of levan were 231.29 ± 3.76% and 97.34 ± 1.72%, respectively. These might have implications in food and medicine, as well as in pharmaceutical industries.

How can the urban landscape affect urban vitality at the street block level? A case study of 15 metropolises in China

Urban vitality, as a metric, measures the attractiveness and competitiveness of a city and is a driver of development. As the physical and social space of human activities, the urban landscape has close connections with urban vitality according to classical theories. However, limited quantitative criteria for the urban landscape and gaps between macro urban planning and micro design create difficulties when constructing a vibrant city. In this study, we quantitatively examined the relationship between the urban landscape and urban vitality at the street block level using geospatial open data to discover where, how, and to what extent we could improve urban vitality, taking 15 Chinese metropolises as a case study. Results indicate that, among the three aspects of the urban landscape considered, the city plan pattern has the highest effect on stimulating vitality, followed by the land use and the patterns of building form. Specifically, the three-dimensional form of buildings has a greater effect than a two-dimensional form. In addition, convenient transportation, a compact block form, diverse buildings, mixed land use, and high buildings are the main characteristics of vibrant blocks. The results also show that the effects of the urban landscape have spatial variations and obvious diurnal discrepancies. Furthermore, over 20 and 33% of the blocks in these cities are identified as low-vitality blocks during the day and night, respectively, and are then categorized into six different types. The identification of the common characteristics of these low-vitality blocks can be taken as references for designing a vibrant urbanity.

Conservation of the Lyre from Grave 48 in the Area between the So-Called ‘Eriai’ Gates and the Dipylon (470–50 BC)

Abstract This paper focuses on the conservation of the lyre (chelys) of Grave 48, from the area between the so-called ‘Eriai’ Gates and the Dipylon. First, it describes the lifting of the lyre (sound box) from the ground and the recovery of the fragile plaques and fragments from the compact block of soil in the laboratory. Subsequently, it presents the extensive conservation work undertaken by the present writer and her team. Furthermore, it summarizes the conclusions of the X-Radiography and Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) examinations of the sound box and the string holder and provides information about the biochemistry, structure and decay of the tortoise shell. In conclusion, the collaboration between conservator and archaeomusicologist, during the remedial conservation treatment, was of great importance, and helped with the identification of the plaques and restoration of the lyre.

High-Performance CML approximate full adders for image processing application of laplace transform

PurposeThe high demand for fast, energy-efficient, compact computational blocks in digital electronics has led the researchers to use approximate computing in applications where inaccuracy of outputs is tolerable. The purpose of this paper is to present two ultra-high-speed current-mode approximate full adders (FA) by using carbon nanotube field-effect transistors.Design/methodology/approachInstead of using threshold detectors, which are common elements in current-mode logic, diodes are used to stabilize voltage. Zener diodes and ultra-low-power diodes are used within the first and second proposed designs, respectively. This innovation eliminates threshold detectors from critical path and makes it shorter. Then, the new adders are employed in the image processing application of Laplace filter, which detects edges in an image.FindingsSimulation results demonstrate very high-speed operation for the first and second proposed designs, which are, respectively, 44.7 per cent and 21.6 per cent faster than the next high-speed adder cell. In addition, they make a reasonable compromise between power-delay product (PDP) and other important evaluating factors in the context of approximate computing. They have very few transistors and very low total error distance. In addition, they do not propagate error to higher bit positions by generating output carry correctly. According to the investigations, up to four inexact FA can be used in the Laplace filter computations without a significant image quality loss. The employment of the first and second proposed designs results in 42.4 per cent and 32.2 per cent PDP reduction compared to when no approximate FA are used in an 8-bit ripple adder.Originality/valueTwo new current-mode inexact FA are presented. They use diodes as voltage regulators to design current-mode approximate full-adders with very short critical path for the first time.

Wideband Self‐Grounded Bow‐Tie Antenna for Thermal MR

The objective of this study was the design, implementation, evaluation and application of a compact wideband self-grounded bow-tie (SGBT) radiofrequency (RF) antenna building block that supports anatomical proton (1 H) MRI, fluorine (19 F) MRI, MR thermometry and broadband thermal intervention integrated in a whole-body 7.0 T system. Design considerations and optimizations were conducted with numerical electromagnetic field (EMF) simulations to facilitate a broadband thermal intervention frequency of the RF antenna building block. RF transmission (B1 + ) field efficiency and specific absorption rate (SAR) were obtained in a phantom, and the thigh of human voxel models (Ella, Duke) for 1 H and 19 F MRI at 7.0 T. B1 + efficiency simulations were validated with actual flip-angle imaging measurements. The feasibility of thermal intervention was examined by temperature simulations (f = 300, 400 and 500 MHz) in a phantom. The RF heating intervention (Pin = 100 W, t = 120 seconds) was validated experimentally using the proton resonance shift method and fiberoptic probes for temperature monitoring. The applicability of the SGBT RF antenna building block for in vivo 1 H and 19 F MRI was demonstrated for the thigh and forearm of a healthy volunteer. The SGBT RF antenna building block facilitated 19 F and 1 H MRI at 7.0 T as well as broadband thermal intervention (234-561 MHz). For the thigh of the human voxel models, a B1 + efficiency ≥11.8 μT/√kW was achieved at a depth of 50 mm. Temperature simulations and heating experiments in a phantom demonstrated a temperature increase ΔT >7 K at a depth of 10 mm. The compact SGBT antenna building block provides technology for the design of integrated high-density RF applicators and for the study of the role of temperature in (patho-) physiological processes by adding a thermal intervention dimension to an MRI device (Thermal MR).

Effect of curing condition and carbonization enhancement on mechanical properties of fly ash -desulfurization gypsum - steel slag blocks

This research demonstrates the effect of curing conditions and carbonization enhancement on mechanical properties of fly ash (FA) - desulfurization gypsum (FGD) - steel slag (SS) gelation blocks. Five curing conditions, including dry-air curing, hot and humid curing, autoclave curing, hot and humid+autoclave curing, autoclave+hot and humid curing, were studied. The experimental results showed that the gelation block under the hot and humid+autoclave curing condition had the highest compressive strength, reaching 35.8MPa. The microstructural characterization of the gelation block by X-ray diffraction (XRD), Fourier-transfer infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA) and Scanning electron microscopy (SEM) indicated that the hot and humid + autoclave curing was favorable for producing more C-S-H gels and promoting the conversion of C-S-H gels to tobermorite crystals on the gelation block. Under the hot and humid+autoclave curing condition, both the tobermorite crystals and C-S-H gels resulted in more compact gelation blocks and thus their higher mechanical properties. The cured gelation block was subjected to enhanced carbonation, which resulted in a more compact gelation block with its pores filled with nano-size calcium carbonate and thus further improvement in its compressive strength by 19.6 %. The physical effect of enhanced carbonation on the gelation block is increased mass by 1.95 %, indicating that approximately 1.95 % of CO2 of the mass of the respective gelation block can be absorbed.

Beyond nearly zero energy urban design: A holistic microclimatic energy and environmental quality evaluation workflow

Despite the urgent global call for an energy transition and the promotion of health and well-being in cities, a holistic approach to evaluating the trade-offs between an urban energy balance and environmental quality considerations is lacking. This paper bridges this gap by introducing a Grasshopper digital workflow through which the impacts of a wide range of building and urban design parameters on both energy performance and environmental quality can be effectively evaluated. This workflow is tested here for both theoretical and site-specific urban test cases in the context of Tel Aviv. For these test cases, the performance metrics - energy load match, spatial daylight autonomy and universal thermal climate index - were calculated using EnergyPlus, Radiance and ENVI-met simulation engines for different block typologies and were then analyzed. The results showed that among the block typologies, the courtyard achieved the optimal combination across the tested environmental criteria, despite the daylight and energy generation penalty associated with self-shading in compact block typologies. This workflow highlights the performative tradeoffs between energy and environmental quality considerations and can thus help urban designers achieve not only a lower environmental impact but also regenerative and healthier design outcomes.

Mechanical and thermal characterization of compact blocks made of clayey earth with wood ashes addition

The objective of this study is to evaluate the influence of wood ashes on the mechanical and thermal characteristics of the clayey earth-ashes compound (CEAC) compressed blocks. Variable mass percentages of 0% to 60% of wood ashes were incorporated to clayey earth stabilized with 10% of cement. The physical characteristics of the clayey earth were determined according to the protocols of the french association of normalization. The manufactured blocks were subjected to mechanical tests: simple compression and tensile by bending. The thermal conductivity was then appreciated by the method of the hot strip. The blocks made with a mixture of “90% clayey earth” and “10% cement”, usually used in construction in Benin, served as a reference material. From the results obtained, it appears that the clayey earth used is a soil A2ts: fine clayed sand in a very dry state. The results of the mechanical and thermal tests show that for an addition of wood ashes between 10% and 20% by weight, the performances of the blocks are significantly improved. The CEAC blocks formulated from 80% of the mixture “90% of clayey earth and 10% of cement” and 20% of wood ashes can be used as building materials.

Quantitative analysis of fruit size and fruit number in <i>Solanum aethiopicum</i> group

Fruit length and width, fruits per cluster and fruit clusters per plant are components of fruit yield in fruit vegetable. Inheritance studies in scarlet eggplant is limited due to inadequate research, and Solanum aethiopicum in an underutilized crop. The objectives of this study were to evaluate inheritance and genetic action, heritability and heterosis for fruit length and diameter, fruits per cluster and fruit cluster per plant in Solanum aethiopicum Gilo and Shum groups. Six generations (P1, P2, F1, F2, BC1 and BC2) from intra species hybridization were evaluated in a compact family block design with six blocks in three replications. Significant scaling and joint scaling tests for fruits clusters per plant and fruits per clusters indicated inadequacy of additive-dominance model. Additive gene action was important for fruit length and fruit clusters per plant, while dominance gene action moderates inheritance of fruit diameter and fruits per cluster. With dominance gene, hybrid breeding is worthwhile to undertake. The opposite signs of dominance and dominance by dominance digenic interaction for fruit clusters per plant showed a duplicate type of epistasis. Positive heterosis for Absolute Mid Parent Heterosis and Relative Mid Parent Heterosis implied sufficient divergence for fruit length and a platform for genetic improvement. High narrow sense heritability for traits predicts a better effectiveness of selection.

A Compact Building Block With Two Shared-Aperture Antennas for Eight-Antenna MIMO Array in Metal-Rimmed Smartphone

In this paper, a compact building block composed of a slot antenna and a loop antenna is proposed. The slot antenna and the loop antenna share a rectangular clearance, which improves the compactness of the building block effectively. Although the slot and the loop have overlapped completely, the proposed building block exhibits good isolation (better than 19 dB) without any external decoupling structure. Four such building blocks are used to implement a compact eight-port multiple-input multiple-output (MIMO) array operating at 3.5 GHz band (3.4–3.6 GHz) for fifth-generation (5G) metal-rimmed smartphone applications. The proposed eight-antenna MIMO array exhibits good isolation of better than 16 dB across the whole operating band. The measured efficiencies of the proposed MIMO array were between 59% and 73%, and its corresponding measured envelope correlation coefficients (ECCs) were better than 0.05. Furthermore, the calculated channel capacity of the proposed MIMO array with 20 dB signal-to-noise ratio (SNR) was about 38.2–39.8 bps/Hz across the desired bands (3.4–3.6 GHz). The measured results confirm that the proposed MIMO array is a good candidate for 5G terminals.

A Low Power Flash ADC using Single-Electron Transistor

This paper proposes an analog-digital converter (ADC) using Single-electron transistor (SET).Single Electron Transistor is Nanodevice having a small quantum dot or island instead of the channel that works on the principle of Coulomb blockadewhich allows one electron tunnelingat a time from source to drain terminal. SET operates at low voltage and consumes lesspower. The proposed Flash ADC consists of SET based priority encoder and comparator circuits. The proposed design offers large input/output voltage swing, ultra-low power, compact circuit block for ADC compared to SET/CMOS hybrid amplifier-based ADC. In this paper, we have designed a 4-bit and 8bitFlash ADC using SET operating at room temperature and the performance estimationwas performed by using the CADENCE VIRTUOSO simulator.

Study for surface pitting of a guide roller at combined sizing blocks using the ultrasonic processing method

This paper discusses how roller marks resulting from compact sizing block form on guide rollers and presents methods to reduce these marks. Ultrasonic nanocrystal surface modification (UNSM) is generally applied to reduce roller marks and improve wear resistance. UNSM treatment improves roller surface hardness, ensures wear resistance, and extends life cycle. This study confirmed that the minimum roller threshold hardness value for preventing surface defects must be 56 HRc. In addition, this study presents the UNSM processing conditions that can produce the maximum effect with the minimum amount of time for guide rollers that are being used without any surface modification. These conditions confirmed that the time required for guide roller inspections can be reduced by 50% or more. The applicability of this method can be expanded to various fields related to steel-making operations.

Selection of circuit geometry for miniaturized microwave components based on concurrent optimization of performance and layout area

The paper presents a framework for automated EM-driven circuit geometry selection of miniaturized microwave components. Selection of a particular layout is based directly on miniaturization rates achieved for a set of candidate circuit geometries. Size reduction of the considered structures is obtained by replacing their main building blocks (i.e., conventional transmission lines) with slow-wave composite cells and meander lines. The proposed method primarily aims at minimization of the structure layout area by adjusting all relevant geometry parameters of its compact building blocks. At the same time, the process ensures satisfying the assumed design requirements by means of a penalty function approach. The problem at hand is solved iteratively using a trust-region-embedded gradient search with the Jacobian matrix estimated at the level of a coarse-discretization EM model of individual circuit building blocks for improved computational efficiency. The proposed methodology is verified by two case studies involving branch-line and rat-race couplers. Each design example is considered in eight different layout versions. The miniaturization rates obtained for the considered circuit geometries range between 63.9% and 76% for the first application example, as well as 80.6% and 87.5% for the second one, respectively. Experimental data validate the reliability of the proposed approach.

A compact 3D block cutting and contact searching algorithm

The geometry relation and the contact point-pairs detection between two three dimensional (3D) objects with arbitrary shapes are essential problems involved in discontinuous computation and computational geometry. This paper reported a geometry relation judgment and contact searching algorithm based on Contact Theory. A contact cover search algorithm is proposed to find all the possible contact cover between two blocks. Two blocks can come to contact only on these covers. Each contact cover can define a possible contact point-pair between two blocks. Data structure and flow chart are provided, as well as some examples in details. Contact problems involving concave blocks or parallel planes are considered to be very difficult in past and are solved by this algorithm. The proposed algorithm is compacted and applicable to the discontinuous computation, such as robotic control, rock mass stability, dam stability etc. A 3D cutting and block searching algorithm is also proposed in this study and used to search the outer boundary of the 3D entrance block when 3D concave blocks are encountered. The 3D cutting and block searching algorithm can be also used to form the block system for jointed rock.

Design of compact residential blocks for sustainable urban regeneration: Determination of consistent qualitative criteria

Given the current ecological problems, it is nowadays necessary to reduce consumption. Demographic growth, economic growth patterns, lifestyles and consumption are leading to forms of unsustainable urban development, requiring ever-increasing resources in terms of land, materials and energy. This paper examines how architectural and urban research can help to mitigate this phenomenon while meeting the needs of the population. It is essential to examine the concept of reasonable density and compact urban typologies in order to develop our cities in a sustainable and positive way, thus limiting the misuse of natural spaces and preserving biodiversity in the face of territorial challenges. The question is, therefore, how to construct cities that comply with sufficiently strong criteria of compactness to reduce their consumption without undermining their attractiveness or quality of life. Design and planning tools are lacking in this area. The research on which this paper is based already enabled us to identify criteria that can be used for analytical purposes and to help design morphologies that satisfy the needs of integrated and objective compactness. These criteria could in the future facilitate the development, at infra-local level, of new compact urban groups, predominantly composed of housing, in accordance with a target density. Unfortunately, there are many, sometimes contradictory criteria of compactness, depending on the target scales and objectives. A compact project considering built-up and unbuilt areas makes it possible to reduce not only areas to be urbanised but also lost areas and the use of materials. Nevertheless, an exaggeration of the concept may result in the area devoted to housing being too small, a loss of luminosity and an increase in shadow effects, the disappearance of separate outside areas or a problem of accessibility. Accordingly, targeting urban compactness gives rise to a difficult choice between various quantitative and qualitative parameters.

Influence of context-sensitive urban and architectural design factors on the energy demand of buildings in Toulouse, France

This research aims to identify the statistical sensitivity of multi-scale urban design factors regarding buildings’ energy demand located in three districts in the city of Toulouse, France. The research method is composed of four main steps: (a) three typical urban blocks of Toulouse are parametrized, considering factors ranging from the urban form to the building material scales; (b) a fractional factorial sampling method is applied which allows elaborating statistically representative and non-redundant scenarios from all design variables and for each specific urban district; (c) the urban energy models generated are interactively assessed regarding the annual buildings’ heating and cooling loads for the temperate climate context of Toulouse, France; (d) through a global sensitivity analysis, results obtained are estimated through a statistic hypothesis test, which allows identifying the influence of the design variables on each energy response of interest. Results show that urban multi-scale design variables may have divergent influence on the same energy response when the urban form context changes. For traditional urban compact blocks, two less current urban form factors considered in this study (the courtyard aspect ratio and the standard-deviation of the built height) account for almost 50% of the overall impact on heating demand of buildings while building and envelope scale factors, such as glazing window properties, have more influence for pavilions and slabs urban blocks. The relevance of certain factors was strongly linked to their typologies or to their urban environment.

Deterioration of exposed buffer block: desiccation shrinkage and cracking

In high-level radioactive waste (HLW) repositories, buffer blocks are used for constructing engineering barrier to intercept radionuclides. Deterioration of exposed buffer blocks during their manufacture, storage, and transport may enlarge the hydraulic conductivity of an engineering barrier, reducing the barrier’s efficacy. It is not easy to monitor the shrinkage displacement by traditional tools because the shrinkage is less than 1 mm per day, while the monitoring length of the block is as large as 350 mm. Additionally, the cracks are often too narrow to allow for an accurate measurement of their depths. For this study, we used Gaomiaozi (GMZ) bentonite and quartz sand at a 7:3 mass ratio to compact fan-shape buffer blocks, and then exposed those blocks in an indoor environmental condition, which allowed desiccation of the blocks to occur. We monitored the overall and surface shrinkage of the blocks employing fixed dial indicators (FDIs) and digital image correlation (DIC), respectively. We excavated subsamples containing cracks from a desiccated block at various depths and estimated the depth of the cracks using Brazilian split tests. We also investigated the microstructure evolution of the blocks with mercury intrusion porosimetry (MIP) after exposure. Hierarchical evaporation of the block’s moisture was observed because the evaporating surface migrated inward rapidly, which led to the absence of initial evaporation stage. The shrinkage displacements of each measuring line were similar, while the longer measuring lines presented less shrinkage strain, indicating the uneven shrinkage. Moreover, the surface shrinkage of the blocks was greater than the overall shrinkage, revealing the interior of the blocks to be resistant to change during desiccation. Besides, the blocks’ inner pores showed less change, while the inter-aggregate pores on the block surface shrank visibly after exposure. The depth of the desiccated cracks was less than 26 mm, as estimated by the distribution of tensile strength. Because we found the varied deterioration levels between the block’s surface and interior, we determined that its structural integrity and efficacy were not as compromised as its surface seemed to indicate.

Generation mean analysis for yield and grain quality traits in rice (Oryza sativa L.)

Three cross combinations each having P1, P2, F1, F2, BC1 and BC2 were evaluated in Compact Family Block Design with three replications to estimate the genetic parameters. Analysis of variance revealed significant differences among generations in all the characters studied except grain breadth in all the three crosses, and kernel length after cooking in cross III. The significance of scaling tests (A, B, C and D) indicated appreciable amount of epistasis present in different characters of three cross combinations under study, indicating the failure of a simple genetic model to explain the genetic system controlling the traits except grain breadth in all the three cross combinations and grain length/breadth ratio in cross combination II.

Evaluation of genetic variability, heritability and genetic advance in blackgram [Vigna mungo (L.) Hepper

An attempt was made to study blackgram germplasm with an objective to develop genetically diverse genotypes accompanied with high heritable components of yield contributing traits. The experimental material comprised of 21 blackgram genotypes, was examined during kharif 2015 and 2016. Experimental study conducted during kharif 2015, was mainly relied on selection of transgressive segregants, which were further analyzed in Compact Family Block Design during kharif 2016. The results depicted that families and progenies within families were significantly different for majority of the traits and found to be highly variable for biological yield, harvest index and seed yield. High heritability coupled with high genetic advance were recorded for plant height (74.15%, 33.12%), branches per plant (84.34%, 40.55%), biological yield (83.51%, 69.11%) and seed yield (84.50%, 66.11%). Thus, the present findings could be beneficial to develop superior genotypes through selection in blackgram breeding program.