scholarly journals Optimization of Tuned Mass Dampers to Improve the Earthquake Resistance of High Buildings

Author(s):  
Rolf Steinbuch

To prevent high buildings in endangered zones suffering from seismic attack, TMD are applied successfully. In many applications the dampers are placed along the height of the edifice to reduce the damage during the earthquake. The dimensioning of TMD is a multidimensional optimisation problem with many local maxima. To find the absolute best or a very good design, advanced optimization strategies have to be applied. Bionic optimization proposes different methods to deal with such tasks but requires many repeated studies of the buildings and dampers design. To improve the speed of the analysis, the authors propose a reduced model of the building including the dampers. A series of consecutive generations shows a growing capacity to reduce the impact of an earthquake on the building. The proposals found help to dimension the dampers. A detailed analysis of the building under earthquake loading may yield an efficient design.

Author(s):  
Rolf Steinbuch

To prevent high buildings in endangered zones suffering from seismic attack, TMD are applied successfully. In many applications the dampers are placed along the height of the edifice to reduce the damage during the earthquake. The dimensioning of TMD is a multidimensional optimisation problem with many local maxima. To find the absolute best or a very good design, advanced optimization strategies have to be applied. Bionic optimization proposes different methods to deal with such tasks but requires many repeated studies of the buildings and dampers design. To improve the speed of the analysis, the authors propose a reduced model of the building including the dampers. A series of consecutive generations shows a growing capacity to reduce the impact of an earthquake on the building. The proposals found help to dimension the dampers. A detailed analysis of the building under earthquake loading may yield an efficient design.


2005 ◽  
pp. 53-68 ◽  
Author(s):  
R. Kapeliushnikov ◽  
N. Demina

The paper provides new survey evidence on effects of concentrated ownership upon investment and performance in Russian industrial enterprises. Authors trace major changes in their ownership profile, assess pace of post-privatization redistribution of shareholdings and provide evidence on ownership concentration in the Russian industry. The major econometric findings are that the first largest shareholding is negatively associated with the firm’s investment and performance but surprisingly the second largest shareholding is positively associated with them. Moreover, these relationships do not depend on identity of majority shareholders. These results are consistent with the assumption that the entrenched controlling owners are engaged in extracting "control premium" but sizable shareholdings accumulated by other blockholders may put brakes on their expropriating behavior and thus be conductive for efficiency enhancing. The most interesting topic for further more detailed analysis is formation, stability and roles of coalitions of large blockholders in the corporate sector of post-socialist countries.


2015 ◽  
Vol 156 (15) ◽  
pp. 592-597
Author(s):  
László Szerafin ◽  
János Jakó ◽  
Ferenc Riskó

Introduction: The low peripheral absolute lymphocyte and high monocyte count have been reported to correlate with poor clinical outcome in various lymphomas and other cancers. However, a few data known about the prognostic value of absolute monocyte count in chronic lymphocytic leukaemia. Aim: The aim of the authors was to investigate the impact of absolute monocyte count measured at the time of diagnosis in patients with chronic lymphocytic leukaemia on the time to treatment and overal survival. Method: Between January 1, 2005 and December 31, 2012, 223 patients with newly-diagnosed chronic lymphocytic leukaemia were included. The rate of patients needing treatment, time to treatment, overal survival and causes of mortality based on Rai stages, CD38, ZAP-70 positivity and absolute monocyte count were analyzed. Results: Therapy was necessary in 21.1%, 57.4%, 88.9%, 88.9% and 100% of patients in Rai stage 0, I, II, III an IV, respectively; in 61.9% and 60.8% of patients exhibiting CD38 and ZAP-70 positivity, respectively; and in 76.9%, 21.2% and 66.2% of patients if the absolute monocyte count was <0.25 G/l, between 0.25–0.75 G/l and >0.75 G/l, respectively. The median time to treatment and the median overal survival were 19.5, 65, and 35.5 months; and 41.5, 65, and 49.5 months according to the three groups of monocyte counts. The relative risk of beginning the therapy was 1.62 (p<0.01) in patients with absolute monocyte count <0.25 G/l or >0.75 G/l, as compared to those with 0.25–0.75 G/l, and the risk of overal survival was 2.41 (p<0.01) in patients with absolute monocyte count lower than 0.25 G/l as compared to those with higher than 0.25 G/l. The relative risks remained significant in Rai 0 patients, too. The leading causes of mortality were infections (41.7%) and the chronic lymphocytic leukaemia (58.3%) in patients with low monocyte count, while tumours (25.9–35.3%) and other events (48.1 and11.8%) occurred in patients with medium or high monocyte counts. Conclusions: Patients with low and high monocyte counts had a shorter time to treatment compared to patients who belonged to the intermediate monocyte count group. The low absolute monocyte count was associated with increased mortality caused by infectious complications and chronic lymphocytic leukaemia. The absolute monocyte count may give additional prognostic information in Rai stage 0, too. Orv. Hetil., 2015, 156(15), 592–597.


2021 ◽  
Vol 13 (8) ◽  
pp. 1485
Author(s):  
Naveen Ramachandran ◽  
Sassan Saatchi ◽  
Stefano Tebaldini ◽  
Mauro Mariotti d’Alessandro ◽  
Onkar Dikshit

Low-frequency tomographic synthetic aperture radar (TomoSAR) techniques provide an opportunity for quantifying the dynamics of dense tropical forest vertical structures. Here, we compare the performance of different TomoSAR processing, Back-projection (BP), Capon beamforming (CB), and MUltiple SIgnal Classification (MUSIC), and compensation techniques for estimating forest height (FH) and forest vertical profile from the backscattered echoes. The study also examines how polarimetric measurements in linear, compact, hybrid, and dual circular modes influence parameter estimation. The tomographic analysis was carried out using P-band data acquired over the Paracou study site in French Guiana, and the quantitative evaluation was performed using LiDAR-based canopy height measurements taken during the 2009 TropiSAR campaign. Our results show that the relative root mean squared error (RMSE) of height was less than 10%, with negligible systematic errors across the range, with Capon and MUSIC performing better for height estimates. Radiometric compensation, such as slope correction, does not improve tree height estimation. Further, we compare and analyze the impact of the compensation approach on forest vertical profiles and tomographic metrics and the integrated backscattered power. It is observed that radiometric compensation increases the backscatter values of the vertical profile with a slight shift in local maxima of the canopy layer for both the Capon and the MUSIC estimators. Our results suggest that applying the proper processing and compensation techniques on P-band TomoSAR observations from space will allow the monitoring of forest vertical structure and biomass dynamics.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ammar Ali Abd ◽  
Samah Zaki Naji ◽  
Ching Thian Tye ◽  
Mohd Roslee Othman

Abstract Liquefied petroleum gas (LPG) plays a major role in worldwide energy consumption as a clean source of energy with low greenhouse gases emission. LPG transportation is exhibited through networks of pipelines, maritime, and tracks. LPG transmission using pipeline is environmentally friendly owing to the low greenhouse gases emission and low energy requirements. This work is a comprehensive evaluation of transportation petroleum gas in liquid state and compressible liquid state concerning LPG density, temperature and pressure, flow velocity, and pump energy consumption under the impact of different ambient temperatures. Inevitably, the pipeline surface exchanges heat between LPG and surrounding soil owing to the temperature difference and change in elevation. To prevent phase change, it is important to pay attention for several parameters such as ambient temperature, thermal conductivity of pipeline materials, soil type, and change in elevation for safe, reliable, and economic transportation. Transporting LPG at high pressure requests smaller pipeline size and consumes less energy for pumps due to its higher density. Also, LPG transportation under moderate or low pressure is more likely exposed to phase change, thus more thermal insulation and pressure boosting stations required to maintain the phase envelope. The models developed in this work aim to advance the existing knowledge and serve as a guide for efficient design by underling the importance of the mentioned parameters.


2020 ◽  
pp. 1-6
Author(s):  
Rebar N. Mohammed

Hematopoietic stem cells (HSCs) are a rare population of cells that reside mainly in the bone marrow and are capable of generating and fulfilling the entire hematopoietic system upon differentiation. Thirty-six healthy donors, attending the HSCT center to donate their bone marrow, were categorized according to their age into child (0–12 years), adolescence (13–18 years), and adult (19–59 years) groups, and gender into male and female groups. Then, the absolute number of HSCs and mature immune cells in their harvested bone marrow was investigated. Here, we report that the absolute cell number can vary considerably based on the age of the healthy donor, and the number of both HSCs and immune cells declines with advancing age. The gender of the donor (male or female) did not have any impact on the number of the HSCs and immune cells in the bone marrow. In conclusion, since the number of HSCs plays a pivotal role in the clinical outcome of allogeneic HSC transplantations, identifying a younger donor regardless the gender is critical.


Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5190
Author(s):  
Cristina Medina-Bailon ◽  
Naveen Kumar ◽  
Rakshita Pritam Singh Dhar ◽  
Ilina Todorova ◽  
Damien Lenoble ◽  
...  

In this work, we present a comprehensive analytical model and results for an absolute pH sensor. Our work aims to address critical scientific issues such as: (1) the impact of the oxide degradation (sensing interface deterioration) on the sensor’s performance and (2) how to achieve a measurement of the absolute ion activity. The methods described here are based on analytical equations which we have derived and implemented in MATLAB code to execute the numerical experiments. The main results of our work show that the depletion width of the sensors is strongly influenced by the pH and the variations of the same depletion width as a function of the pH is significantly smaller for hafnium dioxide in comparison to silicon dioxide. We propose a method to determine the absolute pH using a dual capacitance system, which can be mapped to unequivocally determine the acidity. We compare the impact of degradation in two materials: SiO2 and HfO2, and we illustrate the acidity determination with the functioning of a dual device with SiO2.


2020 ◽  
Vol 13 (3) ◽  
pp. 52-58
Author(s):  
D.P. Melnik ◽  

This article examines the impact of restrictive measures implemented as part of the prevention and protection against the COVID-19 pandemic in Russia. A detailed analysis of the activities of customs authorities (as a state structure) and participants in foreign economic activity in a pandemic is carried out. At the end of the article, conclusions are drawn about the appropriateness of the management decisions taken, and further prospects for the development of economic digitalization in Russia are considered


Author(s):  
Roland Fletcher

The materiality of urbanism encompasses the words and actions by which we relate ourselves to it, the economics of its creation and maintenance, the impact of the material on the viability of community life, and also the long-term trajectories of urban growth and decline. Archaeological approaches to urban materiality tend to focus on how people seek to use the material and also emphasize what the material meant, in verbal terms, to its users. This article focuses on urban materialities, its meaning, magnitude, friction, and outcomes. This article further discusses words, metaphors, and urban materials. In discussing metaphor the material scholars have recognized ‘an inherent problem in the precise relationship between a world of words and world of things’. This article discusses the process of analyzing transformation through time. A detailed analysis on the growth and changing trends in urban industrialization concludes this article.


2013 ◽  
Vol 12 (1) ◽  
pp. 73-88 ◽  
Author(s):  
Timothy Mitchener-Nissen

When assessing any security technology which impacts upon privacy, whether this constitutes a new technology or the novel application of existing technologies, we should do so by examining the combined effect of all security interventions currently employed within a society. This contrasts with the prevailing system whereby the impact of a new security technology is predominantly assessed on an individual basis by a subjective balancing of the security benefits of that technology against any reductions in concomitant rights, such as privacy and liberty. I contend that by continuing to focus on the individual effect, as opposed to the combined effects, of security technologies within a society the likelihood of sleep-walking into (or indeed waking-up in) an absolute surveillance society moves from a possible future to the logically inevitable future. This conclusion is based on two underlying assertions. Firstly that assessing a technology often entails a judgement of whether any loss in privacy is legitimised by a justifiable increase in security; however one fundamental difference between these two rights is that privacy is a finite resource with identifiable end-states (i.e. absolute privacy through to the absolute absence of privacy) whereas security does not have two finite end-states (while there exists the absolute absence of security, absolute security is an unobtainable yet desired goal). The second assertion, which relies upon the validity of the first, holds that one consequence of absolute security being unobtainable yet desirable is that new security interventions will continuously be developed, each potentially trading a small measure of privacy for a small rise in security. Examined individually each intervention may constitute a justifiable trade-off. However this approach of combining interventions in the search for ever greater security will ultimately reduce privacy to zero.


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