Organic Derivatives of Layered Inorganics Having the Second Stage Structure

It is important to accurately determine the vibration characteristics of wooden buildings to evaluate their seismic performance. This study aims to determine the vibration characteristics of a wooden house at each construction stage and to clarify the factors in their change based on the micro-tremor measurements. The construction process of the wooden house is divided into four stages. In the first stage, the wooden house consists of only columns and beams. In the second stage, the lattice bearing walls are installed in the first stage structure. In the third stage, roofing is added. In the fourth stage, the exterior and interior finishes for the lattice bearing walls are conducted and the entire construction work is completed. Therefore, we conducted micro-tremor measurements a total of four times. Based on the results of the micro-tremor measurements, the stiffness ratio of each element of the wooden house was estimated. The exterior and interior finishes for the lattice load-bearing walls occupy approximately 50–70 % of the overall stiffness and their effect on the stiffness of the wooden house is very large.

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The Origin–Destination Matrix Development

MATEC Web of Conferences ◽

10.1051/matecconf/201929006010 ◽

2019 ◽

Vol 290 ◽

pp. 06010

Author(s):

Vasile Dragu ◽

Eugenia Alina Roman

Keyword(s):

Factor Model ◽

Stage Structure ◽

Decision Making Process ◽

Transport Models ◽

Second Stage ◽

Transport Studies ◽

System Requirements ◽

Actual Mobility

Transport studies are conducted for a better understanding of the actual mobility and for developing transport forecasting models to predict the future transport demand and the changes in travel patterns. Transport planning involves the decision-making process for potential improvements to a community’ s roadway infrastructure. The first transport models used to analyze globally the transport system requirements while nowadays models were rethought as a demand – supply interaction reflecting the correlation between transport and socio-economic development. The transport forecasting methodology use a four stage structure consisting of: trip generation, trip distribution, modal split, traffic assignment. In the second stage of the model, the generated trips for each zone are distributed to all other zones based on the choice of destination. The trip pattern is represented by means of an origin-destination (O-D) matrix. The Growth Factor Model and the Gravity Model are two methods to distribute trips among destinations. The two methods for developing the O-D Matrix are presented and criticized in this paper, showing the similarities and differences between them and highlighting the implications for rigorous determination of future transport demand. A case study is done to emphasize the differences between these models and their implications in carrying out transport studies.

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THE SECOND STAGE OF STRESSED-DEFORMED CONDITION OF REINFORCED CONCRETE STRUCTURES WHEN TURNING WITH BENDING (CASE 2)

International Journal for Computational Civil and Structural Engineering ◽

10.22337/2587-9618-2019-15-4-66-82 ◽

2019 ◽

Vol 15 (4) ◽

pp. 66-82 ◽

Cited By ~ 1

Author(s):

Vladimir Kolchunov ◽

Aleksey Demyanov ◽

Николай Наумов

Keyword(s):

Reinforced Concrete ◽

Cross Section ◽

Strain State ◽

Longitudinal Axis ◽

Concrete Element ◽

Second Stage ◽

Tangential Forces ◽

Shaped Crack ◽

Derivatives Of ◽

Spatial Section

It is proposed a complex resistance computational model of reinforced concrete constructions in buildings and structures under the action torsion with bending. It consists of from the block near the support (formed by a spatial crack and a compressed concrete zone closed by it - a spatial section k) and a second block, which is formed by a vertical cross section I-I passing perpendicularly to the longitudinal axis of the reinforced concrete element along the edge of the compressed zone, which closes the spatial spiral-shaped crack. The case when the greatest influence on the stress-strain state of structures has the effect of torque is considered (case 2). In this case, as the calculated forces are taken into account in the spatial section: normal and tangential forces in the concrete of the compressed zone; components of axial and “dowel” efforts in the working reinforcement, intersected by a spiral spatial crack. The resolving equations are constructed that form a closed system and the Lagrange function is unified. Using the partial derivatives of the constructed function with respect to all the variables entering into it and equating them to zero, an additional system of equations is constructed. The dependence is obtained after the corresponding algebraic transformations, that allows us to search for the projection of a dangerous spatial crack.

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Benchmarking Wind Farm Projects by Means of Series Two-Stage DEA

Clean Technologies ◽

10.3390/cleantechnol2030022 ◽

2020 ◽

Vol 2 (3) ◽

pp. 365-376

Author(s):

Ioannis E. Tsolas

Keyword(s):

Wind Farm ◽

Stage Structure ◽

Operational Efficiency ◽

Operating Efficiency ◽

Data Envelopment ◽

Construction Process ◽

Two Stage ◽

Investment Performance ◽

Second Stage ◽

Using Data

This paper presents a data envelopment analysis (DEA) approach to benchmark a group of wind farm (WF) projects in Greece by employing a series two-stage structure. In the first stage, the investment performance of projects is evaluated using contract data and site wind conditions, though in the second stage the WF operational efficiency is evaluated using data on production inputs and output. Inefficiency occurs in both the construction and operating stages, but the construction process appears to be more inefficient relative to the operating phase. Moreover, WF size is related to operating efficiency and sensitivity analysis results identify wind speed and WF installation capacity as the factors that affect the investment performance and operational efficiency, respectively. The proposed approach is an addition to the existing literature and it can be used by managers and facility operators.

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Fuzzy Thrust Staging Kinematics for the NERVA Strap-On Boosters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.1611 ◽

2012 ◽

Vol 463-464 ◽

pp. 1611-1615

Author(s):

Radu Dan Rugescu ◽

Stefan Staicu ◽

Seyed Mohamadreza Mahmoudian

Keyword(s):

Ignition Delay ◽

Stage Structure ◽

Severe Damage ◽

Second Stage ◽

Main Challenge ◽

Lift Off ◽

The Individual ◽

High Thrust ◽

Very High ◽

Space Launcher

NERVA small space launcher under development in Romania by Politehnica University is based on the solution of hard take-off with three strep-on SRM boosters. Due to the very high thrust enhancement a lift-off loading of more than 40 g-s appears, which is quite challenging. The main challenge is connected with the possible uneven thrust and burn duration of the three SRE-s of the first stage, which we call fuzzy thrust. Experimental data show variations of up to 0.5 seconds in the duration of the powered phase of SRE-s, from a total of 3.0 seconds of a mean burn. Yet undetermined variations in the total ignition delay between individual motors are a stronger concern. While for the unique booster of the standard SA-2 vehicle the ignition delay has no impact, when those engines are forced to work in parallel the individual differences become catastrophic. Severe imbalance between the two lateral engines may occur, ending in a potentially severe damage of the launching rail, possible loss of flight stability along the boost phase and damage of the second stage structure. The problems regarding the efficiency of the propulsion system that accompany this project are considered and solutions are proposed for the high thrust augmentation of the booster stage. Cryogenic vs storable propellants are studied for thrust augmentation of the boosters.

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An Ultra-Low Frequency Active Vertical Vibration Isolator With Geometric Anti-Spring Structure

Volume 4B: Dynamics, Vibration, and Control ◽

10.1115/imece2017-71173 ◽

2017 ◽

Author(s):

Jiamin Yao ◽

Kang Wu ◽

Jin Qian ◽

Guan Wang ◽

Meiying Guo ◽

...

Keyword(s):

Vibration Isolation ◽

Low Frequency ◽

Ground Vibration ◽

Stage Structure ◽

Target Object ◽

Vertical Vibration ◽

Vibration Isolator ◽

Restoring Force ◽

Second Stage ◽

Allowable Load

Vibration isolators have been widely used to keep the target object from the ground vibration in order to improve the measurement accuracy. Nowadays, the ultra-low frequency vibration isolator based on a two-stage structure shows the best performance. Traditionally, vertically suspended springs are usually applied as the second-stage. As the requirement of the low stiffness, the springs need to be long, which brings the disadvantages of relatively large size and small allowable load. A novel ultra-low frequency active vertical vibration isolator is proposed in this paper, which applies geometric anti-spring (GAS) instead of the second-stage suspended springs. The isolated object (the second stage) is supported by GAS fixed on an inner frame (the first stage), and the inner frame is hung with supporting springs from the base of the vibration isolator. The inner frame is driven by a voice coil to track the motion of the isolated object according to the relative motion signal detected by a photoelectric detector. Ideally, GAS provides zero restoring force for the object, thus realizing a long natural resonance period. Experimental results show that the isolator can achieve a resonance period of 14.7 s, compared with a simulated result of 20.7 s. Therefore, it is accessible to reduce the isolator’s volume and increase the allowable load by replacing the traditional second-stage suspended springs with GAS, without harming the vibration isolation effect. Promisingly it will be applied in free-falling and atomic-interference absolute gravimeters, and other precise measurements.

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Rankine–Hugoniot relations for shocks in heterogeneous mixtures

Journal of Fluid Mechanics ◽

10.1017/s0022112006004496 ◽

2007 ◽

Vol 575 ◽

pp. 495-507 ◽

Cited By ~ 22

Author(s):

S. L. GAVRILYUK ◽

R. SAUREL

Keyword(s):

Shock Front ◽

Stage Structure ◽

Compressible Fluids ◽

Shock Propagation ◽

Mechanical Equilibrium ◽

Heterogeneous Mixture ◽

Closed Set ◽

Second Stage ◽

Condensed Materials ◽

Shock Fronts

The conservation of mass, momentum and energy are not sufficient to close a system of jump relations for shocks propagating in a heterogeneous mixture of compressible fluids. We propose here a closed set of relations corresponding to a two-stage structure of shock fronts. At the first stage, microkinetic energy due to the relative motion of mixture components is produced at the shock front. At the second stage, this microkinetic energy disappears inducing strong variations in the thermodynamical states that reach mechanical equilibrium. The microkinetic energy produced at the shock front is estimated by using an idea developed earlier for turbulent shocks in compressible fluids. The relaxation zone between the shocked state and the equilibrium state is integrated over a thermodynamic path a justification of which is provided. Comparisons with experiments on shock propagation in a mixture of condensed materials confirm the proposed theory.

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Altered Fine Structure of B Lymphocytes Correlated with Defective Terminal Differentiation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007237x ◽

1973 ◽

Vol 31 ◽

pp. 386-387

Author(s):

Dale E. Bockman ◽

L. Y. Frank Wu ◽

Alexander R. Lawton ◽

Max D. Cooper

Keyword(s):

Immune Deficiency ◽

B Lymphocytes ◽

Plasma Cells ◽

Present Report ◽

Specific Antigen ◽

Terminal Differentiation ◽

Second Stage ◽

Two Stages ◽

Deficiency Diseases ◽

Cell Line Generation

B-lymphocytes normally synthesize small amounts of immunoglobulin, some of which is incorporated into the cell membrane where it serves as receptor of antigen. These cells, on contact with specific antigen, proliferate and differentiate to plasma cells which synthesize and secrete large quantities of immunoglobulin. The two stages of differentiation of this cell line (generation of B-lymphocytes and antigen-driven maturation to plasma cells) are clearly separable during ontogeny and in some immune deficiency diseases. The present report describes morphologic aberrations of B-lymphocytes in two diseases in which second stage differentiation is defective.

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