scholarly journals Modal Analysis of Selected Measuring Bases and Their Impact on the Recorded Level of Surface Accelerations

2020 ◽  
Vol 10 (9) ◽  
pp. 3128 ◽  
Author(s):  
Krzysztof Robert Czech
Keyword(s):  
Cross Sections ◽  
Natural Frequencies ◽  
Ground Surface ◽  
Human Beings ◽  
3D Design ◽  
Different Types ◽  
Surface Vibrations ◽  
The Time Domain ◽  
The Impact ◽  
Measuring Base

In predicting the impact of vibrations propagated in a ground on newly designed construction objects, it is extremely important to reliably measure the time histories of velocity or acceleration at the site of the planned investment. As some studies show, the method of coupling accelerometers and geophones to the ground can affect not only the level of peak particle accelerations (PPA) or peak particle velocities (PPV)—commonly used in this type of evaluation—but also vibration frequency distribution of recorded signals. This makes it difficult to compare and analyze the results obtained by various research teams. Conclusions based on this type of comparison may be wrong. For this reason, it is extremely important that reliable dynamic measurements related to the propagation of ground surface vibrations should be carried out using not only appropriately selected measuring equipment (with the required sensitivity and measurement ranges—both in the time domain and frequency domain), but also the measurement bases/setups used for mounting various types of transducers, whose natural frequencies will be outside the frequency range relevant to the possible impact of vibrations on buildings and human beings inside. The paper presents the results of modal analyses carried out with the use of Ansys Engineering Simulation and 3D Design Software (based on the Finite Element Method) for three different types of measuring bases used to coupling accelerometers to the ground. Measuring bases selected for numerical analyses were in the form of a stiff steel spike of an X-shaped cross section (a measuring base No. 1) and two steel spikes of L-shaped cross-sections (a measuring bases No. 2 and No. 3). In the places of screwed accelerometers (three different types of IEPE/ICP transducers of varying sensitivity and a weight) point masses were attached to the measuring bases. As a result of the analyses, it was possible to determine the impact of individual methods of coupling of accelerometers to the ground on the reliability of recorded ground surface accelerations. Among others it was concluded that in each analyzed case the lowest natural frequencies of the measuring bases with attached accelerometers significantly exceeded 100 Hz. The widest frequency band free of resonance vibrations can be provided by the measuring base No. 3 (L50 × 50 × 5).

scholarly journals Influence of continuous deformations and tremors of rock mass on a building. Case study

2018 ◽  
Vol 36 ◽  
pp. 01009
Author(s):  
Piotr Strzałkowski
Keyword(s):  
Rock Mass ◽  
Ground Surface ◽  
Surface Vibrations ◽  
The Impact

This work presents an exemplary analysis of the influence of mining exploitations on a building. Continuous deformations of the ground surface in the location of the object were considered. Analysis of the impact of tremors of rock mass on the object was performed. The results of calculations as well as the measurements of surface vibrations accelerations were taken into account. The performed analyses show the influence of a fault on increase of vibrations accelerations.

scholarly journals Determination of Different Structures’ Materials Natural Frequencies using Fuzzy Logic System

2020 ◽  
Vol 9 (3) ◽  
pp. 723-727
Keyword(s):  
Natural Frequency ◽  
Natural Frequencies ◽  
Influential Factor ◽  
Building Structures ◽  
Engineering Applications ◽  
Natural Properties ◽  
Different Types ◽  
The Impact ◽  
Logic System

The impact of structure’s material and dimensions on its natural frequency are lacking in recent literature. The main aim of that paper is investigating material’ characteristics effect on structures natural frequency. Five different types of materials (steel, concrete,wood, plastic and aluminum) which mostly used in engineering applications implemented in this study. A fuzzy system designed and structured for each type of materials. It used to optimize the natural frequency values related to height and area of structure. The results show that whilst the height of the structure is a very influential factor on its natural frequency, the type of material as well as area of the structure are also effective variables. For the same dimensions of the structure, wood shows the highest value of natural frequency, then steel followed by concrete. In addition, the natural frequencies of structures have been assessed against the wind, earthquakes and traffic vibrations. These results can have useful applications and recommendations for engineering and design purposes. Wood can complement natural properties of a range of materials. Implications from this investigation can be useful for heavy machines laboratories, building structures and other engineering applications.

Quota Women Are Threatening to Men

2017 ◽  
Vol 76 (3) ◽  
pp. 107-116 ◽  
Author(s):  
Klea Faniko ◽  
Till Burckhardt ◽  
Oriane Sarrasin ◽  
Fabio Lorenzi-Cioldi ◽  
Siri Øyslebø Sørensen ◽  
...  
Keyword(s):  
Decision Making ◽  
Organizational Performance ◽  
Gender Stereotypes ◽  
Perceived Threat ◽  
Preferential Treatment ◽  
Public Sector Employees ◽  
Different Types ◽  
Low Levels ◽  
Women In Decision Making ◽  
The Impact

Abstract. Two studies carried out among Albanian public-sector employees examined the impact of different types of affirmative action policies (AAPs) on (counter)stereotypical perceptions of women in decision-making positions. Study 1 (N = 178) revealed that participants – especially women – perceived women in decision-making positions as more masculine (i.e., agentic) than feminine (i.e., communal). Study 2 (N = 239) showed that different types of AA had different effects on the attribution of gender stereotypes to AAP beneficiaries: Women benefiting from a quota policy were perceived as being more communal than agentic, while those benefiting from weak preferential treatment were perceived as being more agentic than communal. Furthermore, we examined how the belief that AAPs threaten men’s access to decision-making positions influenced the attribution of these traits to AAP beneficiaries. The results showed that men who reported high levels of perceived threat, as compared to men who reported low levels of perceived threat, attributed more communal than agentic traits to the beneficiaries of quotas. These findings suggest that AAPs may have created a backlash against its beneficiaries by emphasizing gender-stereotypical or counterstereotypical traits. Thus, the framing of AAPs, for instance, as a matter of enhancing organizational performance, in the process of policy making and implementation, may be a crucial tool to countering potential backlash.

The efficiency of application of virtual cross-sections method and hypotheses MELS in problems of wave signal propagation in elastic waveguides with rough surfaces

2016 ◽  
pp. 3564-3575 ◽  
Author(s):  
Ara Sergey Avetisyan
Keyword(s):  
Half Space ◽  
Cross Sections ◽  
Classical Method ◽  
Signal Propagation ◽  
Elastic Half Space ◽  
Layered Systems ◽  
Surface Layers ◽  
Inhomogeneous Surface ◽  
Wave Signal ◽  
The Impact

The efficiency of virtual cross sections method and MELS (Magneto Elastic Layered Systems) hypotheses application is shown on model problem about distribution of wave field in thin surface layers of waveguide when plane wave signal is propagating in it. The impact of surface non-smoothness on characteristics of propagation of high-frequency horizontally polarized wave signal in isotropic elastic half-space is studied. It is shown that the non-smoothness leads to strong distortion of the wave signal over the waveguide thickness and along wave signal propagation direction as well.  Numerical comparative analysis of change in amplitude and phase characteristics of obtained wave fields against roughness of weakly inhomogeneous surface of homogeneous elastic half-space surface is done by classical method and by proposed approach for different kind of non-smoothness.

New Wars and Their Visual Representation: Dead Bodies without Graves/Mourne

2020 ◽  
Vol 2 ◽  
pp. 1-18
Author(s):  
Tuncay Şur ◽  
Betül Yarar
Keyword(s):  
Social Media ◽  
Visual Representation ◽  
Human Beings ◽  
The Public ◽  
Photographic Images ◽  
War Photography ◽  
New Wars ◽  
The Social ◽  
History Of ◽  
The Impact

This paper seeks to understand why there has been an increase in photographic images exposing military violence or displaying bodies killed by military forces and how they can freely circulate in the public without being censored or kept hidden. In other words, it aims to analyze this particular issue as a symptom of the emergence of new wars and a new regime of their visual representation. Within this framework, it attempts to relate two kinds of literature that are namely the history of war and war photography with the bridge of theoretical discussions on the real, its photographic representation, power, and violence.  Rather than systematic empirical analysis, the paper is based on a theoretical attempt which is reflected on some socio-political observations in the Middle East where there has been ongoing wars or new wars. The core discussion of the paper is supported by a brief analysis of some illustrative photographic images that are served through the social media under the circumstances of war for instance in Turkey between Turkish military troops and the Kurdish militants. The paper concludes that in line with the process of dissolution/transformation of the old nation-state formations and globalization, the mechanism and mode of power have also transformed to the extent that it resulted in the emergence of new wars. This is one dynamic that we need to recognize in relation to the above-mentioned question, the other is the impact of social media in not only delivering but also receiving war photographies. Today these changes have led the emergence of new machinery of power in which the old modern visual/photographic techniques of representing wars without human beings, torture, and violence through censorship began to be employed alongside medieval power techniques of a visual exhibition of tortures and violence.

Impact of Environmental Degradation on Human Health

2016 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
_______ Archana ◽  
Charu Datta ◽  
Pratibha Tiwari
Keyword(s):  
Environmental Degradation ◽  
Human Population ◽  
Environmental Problems ◽  
Population Increase ◽  
Human Beings ◽  
The People ◽  
Wide Range ◽  
Different Types ◽  
Economic Institute ◽  
Day By Day

Degradation of environment is one of the most serious challenges before the mankind in today’s world. Mankind has been facing a wide range of problem arising out of the degradation of environment. Not only the areas under human inhabitation, but the areas of the planet without human population have also been suffering from these problems. As the population increase day by day, the amenities are not improved simultaneously. With the advancement of science and technologies the needs of human beings has been changing rapidly. As a result different types of environmental problems have been rising. Environmental degradation is a wide- reaching problem and it is likely to influence the health of human population is great. It may be defined the deterioration of the environment through depletion of resources such as air, water, and soil. The destruction of ecosystem and extinction of wildlife. Environmental degradation has occurred due to the recent activities in the field of socio-economic, institute and technology. Poverty still remains a problem as the root of several environmental problems to create awareness among the people about the ill effect of environmental pollution. In the whole research it is clear that all factors of environmental degradation may be reduced through- Framing the new laws on environmental degradation, Environment friend policy, Controlling all the ways and means of noise, air, soil and water pollution, Through growing more and more trees and by adapting the proper sanitation policy.  

Perception of Professionals towards Effectiveness of Human Resource Information System

2015 ◽  
Vol 4 (3) ◽  
Author(s):  
Bharti Motwani
Keyword(s):  
Information System ◽  
Human Resource ◽  
Training Programme ◽  
Middle Level ◽  
Human Beings ◽  
Human Resource Information System ◽  
Resource Information ◽  
Future Challenges ◽  
Operational Decision Making ◽  
The Impact

Organizations are facing stiff market and other external pulls and pushes, thus HR will become vital source for managing future challenges. HRIS is an information system that makes use of computers to monitor, control, and influence the movement of human beings from the time they indicate their intention to join an organization till the time they separate from it. The purpose of the HRIS is to provide service, in the form of accurate and timely information, to the clients of the system. As there are a variety of potential users of HR information, it may be used for strategic, tactical, and operational decision making (e.g., to plan for needed professionals in a merger), to avoid litigation (e.g., to identify discrimination problems in hiring), to evaluate programmes, policies, or practices (e.g., to evaluate the effectiveness of a training programme), and/or to support daily operations (e.g., to help managers monitor time and attendance of their professionals). However, in order to maximize HRIS success, researchers and practitioners have to know more about its underlying drivers. The study is undertaken looking to the importance of HRIS in the organizations. The paper identifies the factors of HRIS as perceived by professional users. This study is also an attempt to study the impact of designation on identified factors of Human Resource Information System (HRIS). The results of this research will increase researchers comprehension on difference in factors that influence effectiveness of senior and middle-level professionals.

Dynamic model for high-speed rotors based on their experimental characterization

2017 ◽  
Vol 2 (4) ◽  
pp. 25
Author(s):  
L. A. Montoya ◽  
E. E. Rodríguez ◽  
H. J. Zúñiga ◽  
I. Mejía
Keyword(s):  
Dynamic Model ◽  
High Speed ◽  
Natural Frequencies ◽  
Mode Shapes ◽  
Experimental Characterization ◽  
Rotating Systems ◽  
Computing Performance ◽  
The Impact ◽  
Stiffness Distribution ◽  
Good Agreement

Rotating systems components such as rotors, have dynamic characteristics that are of great importance to understand because they may cause failure of turbomachinery. Therefore, it is required to study a dynamic model to predict some vibration characteristics, in this case, the natural frequencies and mode shapes (both of free vibration) of a centrifugal compressor shaft. The peculiarity of the dynamic model proposed is that using frequency and displacements values obtained experimentally, it is possible to calculate the mass and stiffness distribution of the shaft, and then use these values to estimate the theoretical modal parameters. The natural frequencies and mode shapes of the shaft were obtained with experimental modal analysis by using the impact test. The results predicted by the model are in good agreement with the experimental test. The model is also flexible with other geometries and has a great time and computing performance, which can be evaluated with respect to other commercial software in the future.

Situational Breakdowns

2019 ◽  
Author(s):  
Anne Nassauer
Keyword(s):  
United States ◽  
Large Scale ◽  
Contextual Factors ◽  
The United States ◽  
Social Outcomes ◽  
Dynamic Processes ◽  
Collective Decisions ◽  
Different Types ◽  
The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

Geological Field Sketches and Illustrations

2019 ◽  
Author(s):  
Matthew J. Genge
Keyword(s):  
Cross Sections ◽  
Earth Science ◽  
Three Dimensional ◽  
Worked Examples ◽  
Scientific Publications ◽  
Thin Sections ◽  
Geological Features ◽  
Different Types ◽  
The Subject

Drawings, illustrations, and field sketches play an important role in Earth Science since they are used to record field observations, develop interpretations, and communicate results in reports and scientific publications. Drawing geology in the field furthermore facilitates observation and maximizes the value of fieldwork. Every geologist, whether a student, academic, professional, or amateur enthusiast, will benefit from the ability to draw geological features accurately. This book describes how and what to draw in geology. Essential drawing techniques, together with practical advice in creating high quality diagrams, are described the opening chapters. How to draw different types of geology, including faults, folds, metamorphic rocks, sedimentary rocks, igneous rocks, and fossils, are the subjects of separate chapters, and include descriptions of what are the important features to draw and describe. Different types of sketch, such as drawings of three-dimensional outcrops, landscapes, thin-sections, and hand-specimens of rocks, crystals, and minerals, are discussed. The methods used to create technical diagrams such as geological maps and cross-sections are also covered. Finally, modern techniques in the acquisition and recording of field data, including photogrammetry and aerial surveys, and digital methods of illustration, are the subject of the final chapter of the book. Throughout, worked examples of field sketches and illustrations are provided as well as descriptions of the common mistakes to be avoided.

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