scholarly journals Evolution of Clustering Quantified by a Stochastic Method—Case Studies on Natural and Human Social Structures

2020 ◽  
Vol 12 (19) ◽  
pp. 7972
Author(s):  
G.-Fivos Sargentis ◽  
Theano Iliopoulou ◽  
Stavroula Sigourou ◽  
Panayiotis Dimitriadis ◽  
Demetris Koutsoyiannis
Keyword(s):  
Case Studies ◽  
Large Scale ◽  
Spatial Information ◽  
Physical World ◽  
Natural World ◽  
Social Structures ◽  
Societal Challenges ◽  
The Cost ◽  
Organizational Needs ◽  
The Universe

Clustering structures appearing from small to large scales are ubiquitous in the physical world. Interestingly, clustering structures are omnipresent in human history too, ranging from the mere organization of life in societies (e.g., urbanization) to the development of large-scale infrastructure and policies for meeting organizational needs. Indeed, in its struggle for survival and progress, mankind has perpetually sought the benefits of unions. At the same time, it is acknowledged that as the scale of the projects grows, the cost of the delivered products is reduced while their quantities are maximized. Thus, large-scale infrastructures and policies are considered advantageous and are constantly being pursued at even great scales. This work develops a general method to quantify the temporal evolution of clustering, using a stochastic computational tool called 2D-C, which is applicable for the study of both natural and human social spatial structures. As case studies, the evolution of the structure of the universe, of ecosystems and of human clustering structures such as urbanization, are investigated using novel sources of spatial information. Results suggest the clear existence both of periods of clustering and declustering in the natural world and in the human social structures; yet clustering is the general trend. In view of the ongoing COVID-19 pandemic, societal challenges arising from large-scale clustering structures are discussed.

scholarly journals Exploiting Proximity-Based Mobile Apps for Large-Scale Location Privacy Probing

2018 ◽  
Vol 2018 ◽  
pp. 1-22 ◽  
Author(s):  
Shuang Zhao ◽  
Xiapu Luo ◽  
Xiaobo Ma ◽  
Bo Bai ◽  
Yankang Zhao ◽  
...  
Keyword(s):  
Social Networks ◽  
Case Studies ◽  
Real World ◽  
Emission Reduction ◽  
Large Scale ◽  
Location Privacy ◽  
Mobile Apps ◽  
Physical World ◽  
Typical Type ◽  
Location Spoofing

Proximity-based apps have been changing the way people interact with each other in the physical world. To help people extend their social networks, proximity-based nearby-stranger (NS) apps that encourage people to make friends with nearby strangers have gained popularity recently. As another typical type of proximity-based apps, some ridesharing (RS) apps allowing drivers to search nearby passengers and get their ridesharing requests also become popular due to their contribution to economy and emission reduction. In this paper, we concentrate on the location privacy of proximity-based mobile apps. By analyzing the communication mechanism, we find that many apps of this type are vulnerable to large-scale location spoofing attack (LLSA). We accordingly propose three approaches to performing LLSA. To evaluate the threat of LLSA posed to proximity-based mobile apps, we perform real-world case studies against an NS app named Weibo and an RS app called Didi. The results show that our approaches can effectively and automatically collect a huge volume of users’ locations or travel records, thereby demonstrating the severity of LLSA. We apply the LLSA approaches against nine popular proximity-based apps with millions of installations to evaluate the defense strength. We finally suggest possible countermeasures for the proposed attacks.

Big Bang Theory

2018 ◽  
Author(s):  
Matthew Y. Heimburger
Keyword(s):  
Large Scale ◽  
Mechanistic Model ◽  
Albert Einstein ◽  
Physical World ◽  
Big Bang ◽  
Scientific Model ◽  
Social Sciences And Humanities ◽  
Big Bang Theory ◽  
The Big Bang ◽  
The Universe

The Big Bang theory is a scientific model of the universe that posits a state of dense, centralized matter before the current, observable expansion of the universe in one giant explosion. While ‘the Big Bang’ was a phrase first used somewhat facetiously by British astronomer Fred Hoyle in 1949, it rested on earlier theories and observations by George Lamaitre, Albert Einstein, and Edwin Hubble. The implications of Big Bang theory have been far-reaching. For some, the Big Bang’s suggestion of a ‘beginning of time’ lent itself to familiar religious teleology. For others, it provided a rigid, mechanistic model of the physical world, which in turn affected ideas in the social sciences and humanities. This is not to say that Big Bang theory was a ‘grand unifying theory’—even in the 1920s, the rather precise predictions of Einstein’s theories of relativity conflicted with the conclusions of Heisenberg’s Uncertainty Principle and quantum mechanics. Still, the idea that the physical world exists due to the violent expansion (and subsequent contraction) of matter suggests a rather small place for humanity in the larger scheme of things. There is little room or need for free will in such a system—at least when it comes to matters of large-scale significance. Today, the Big Bang often stands as a euphemism for debates over God and human determinism in the universe, and lends itself to philosophic traditions such as nihilism and existentialism.

Plant Sex from Empedocles to Theophrastus

2018 ◽  
Author(s):  
Lincoln Taiz ◽  
Lee Taiz
Keyword(s):  
Direct Observation ◽  
Modern Science ◽  
Physical World ◽  
Natural World ◽  
Biological Information ◽  
Natural Laws ◽  
Physical Laws ◽  
The Universe ◽  
Plant Sex ◽  
Divine Order

“Plant Sex from Empedocles to Theophrastus” investigates Greek philosophies concerning plants. The Pythagoreans and pre-Socratic philosophers taught that the universe was governed by a divine order that could be understood through mathematical or physical laws, and that “natural laws” were discoverable by observation and logic. This tradition eventually gave rise to modern science. Unlike Plato, who viewed the physical world as “shadows,” knowable only through mathematics and abstract philosophy, Aristotle and Theophrastus regarded everything in the natural world that could be perceived by the senses as both real and knowable, and believed direct observation combined with reason and logic were the most reliable guides to truth. They systematized a prodigious amount of biological information, but were unable to elucidate the problem of plant sex. Theophrastus’ failed to understand the so-called “degeneration” of trees grown from seed because it couldn’t be understood without a two-sex model. Biblical theorists fared no better.

scholarly journals Identifying the fitness consequences of sex in complex natural environments

2019 ◽  
Author(s):  
Catherine A. Rushworth ◽  
Yaniv Brandvain ◽  
Tom Mitchell-Olds
Keyword(s):  
Large Scale ◽  
Natural World ◽  
Transplant Experiment ◽  
Biological Traits ◽  
Natural Environments ◽  
Ecological Fitness ◽  
Lifetime Fitness ◽  
Fitness Consequences ◽  
The Cost ◽  
Cost Of Sex

AbstractIn the natural world, sex prevails, despite its costs. While much effort has been dedicated to identifying the intrinsic costs of sex (e.g. the cost of males), few studies have identified the ecological fitness consequences of sex. Furthermore, correlated biological traits that differ between sexuals and asexuals may alter these costs, or even render the typical costs of sex irrelevant. Here we use a large-scale transplant experiment of a North American wildflower to show that sex is associated with reduced lifetime fitness, despite lower herbivory. We separate the effects of sex from hybridity, finding that over-winter survival is elevated in asexuals regardless of hybridity, but herbivores target hybrid asexuals. Survival is lowest in homozygous sexual lineages, implicating inbreeding depression as a cost of sex. Our results show that the consequences of sex are shaped by complex natural environments, correlated traits, and the identity of mates, rather than sex itself.

Inbreeding depression and the cost of inbreeding on seed germination

2015 ◽  
Vol 25 (4) ◽  
pp. 355-385 ◽  
Author(s):  
Jerry M. Baskin ◽  
Carol C. Baskin
Keyword(s):  
Seed Germination ◽  
Case Studies ◽  
Inbreeding Depression ◽  
Life History Traits ◽  
Seed Mass ◽  
Natural World ◽  
Dormancy Breaking ◽  
The Cost ◽  
The Relationship ◽  
Better Than

AbstractWe review the literature on effects of inbreeding depression (ID) on seed germination for 743 case studies of 233 species in 64 families. For 216 case studies, we also review the relationship between mass and germination in inbred vs. outbred seeds. Inbred seeds germinated equally well as outbred seeds in 51.1% of 743 case studies, but better than outbred seeds in only 8.1%. In c. 50.5% of 216 cases, mass of inbred seeds was equal to (38.0%) or larger than (12.5%) that of outbred seeds. The magnitude of ID spans most of the − 1 to +1 range for relative performance for germination of inbred vs. outbred seeds; in contrast to what might be expected, seed germinability often is not negatively correlated with the coefficient of inbreeding (F) or positively corrected with population genetic diversity; neither heterosis nor outbreeding depression for germination is common in crosses between populations; and ID in most endemics is low and does not differ from that of widespread congeners. Our results on the effects of ID on seed mass and germination do not agree with the limited number of comparisons Darwin (1876) made on the effects of selfing vs. outcrossing on these two life-history traits. Recommendations are made on how to improve dormancy breaking and germination procedures in order to make the results of studies on ID more relevant to the natural world.

Cost- und Monitoring-Projekt: Zwei neue forstliche Meinungsumfragen im Vergleich | The Cost- and Monitoring-Projects: A Comparison of Two New Forestry Opinion Polls

2000 ◽  
Vol 151 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Stephan Wild-Eck ◽  
Willi Zimmermann
Keyword(s):  
Large Scale ◽  
Forest Policy ◽  
Forest Economics ◽  
Positive Attitudes ◽  
Federal Institute ◽  
Swiss Confederation ◽  
Institute Of Technology ◽  
The Cost ◽  
Near Future ◽  
Opinion Polls

Two large-scale surveys looking at attitudes towards forests, forestry and forest policy in the second half ofthe nineties have been carried out. This work was done on behalf of the Swiss Confederation by the Chair of Forest Policy and Forest Economics of the Federal Institute of Technology (ETH) in Zurich. Not only did the two studies use very different methods, but the results also varied greatly as far as infrastructure and basic conditions were concerned. One of the main differences between the two studies was the fact that the first dealt only with mountainous areas, whereas the second was carried out on the whole Swiss population. The results of the studies reflect these differences:each produced its own specific findings. Where the same (or similar) questions were asked, the answers highlight not only how the attitudes of those questioned differ, but also views that they hold in common. Both surveys showed positive attitudes towards forests in general, as well as a deep-seated appreciation ofthe forest as a recreational area, and a positive approach to tending. Detailed results of the two surveys will be available in the near future.

Causality Then and Now

1993 ◽  
Vol 10 (2) ◽  
pp. 165-177
Author(s):  
Karen Harding
Keyword(s):  
Quantum Theory ◽  
Common Sense ◽  
Mechanical Model ◽  
Physical World ◽  
Scientific Data ◽  
The World ◽  
The Common ◽  
The Universe ◽  
The Way

Ate appearances deceiving? Do objects behave the way they do becauseGod wills it? Ate objects impetmanent and do they only exist becausethey ate continuously created by God? According to a1 Ghazlli, theanswers to all of these questions ate yes. Objects that appear to bepermanent are not. Those relationships commonly tefemed to as causalare a result of God’s habits rather than because one event inevitably leadsto another. God creates everything in the universe continuously; if Heceased to create it, it would no longer exist.These ideas seem oddly naive and unscientific to people living in thetwentieth century. They seem at odds with the common conception of thephysical world. Common sense says that the universe is made of tealobjects that persist in time. Furthermore, the behavior of these objects isreasonable, logical, and predictable. The belief that the univetse is understandablevia logic and reason harkens back to Newton’s mechanical viewof the universe and has provided one of the basic underpinnings ofscience for centuries. Although most people believe that the world is accutatelydescribed by this sort of mechanical model, the appropriatenessof such a model has been called into question by recent scientificadvances, and in particular, by quantum theory. This theory implies thatthe physical world is actually very different from what a mechanicalmodel would predit.Quantum theory seeks to explain the nature of physical entities andthe way that they interact. It atose in the early part of the twentieth centuryin response to new scientific data that could not be incorporated successfullyinto the ptevailing mechanical view of the universe. Due largely ...

Waste minimization program in Shuaiba Industrial Area

1999 ◽  
Vol 39 (10-11) ◽  
pp. 289-295
Author(s):  
Saleh Al-Muzaini
Keyword(s):  
Solid Waste ◽  
Power Plants ◽  
Large Scale ◽  
Industrial Area ◽  
Waste Minimization ◽  
Regulatory Body ◽  
Eastern Sector ◽  
Western Sector ◽  
Petroleum Companies ◽  
The Cost

The Shuaiba Industrial Area (SIA) is located about 50 km south of Kuwait City. It accommodates most of the large-scale industries in Kuwait. The total area of the SIA (both eastern and western sectors) is about 22.98 million m2. Fifteen plants are located in the eastern sector and 23 in the western sector, including two petrochemical companies, three refineries, two power plants, a melamine company, an industrial gas corporation, a paper products company and, two steam electricity generating stations, in addition to several other industries. Therefore, only 30 percent of the land in the SIA's eastern sector and 70 percent of land in the SIA's western sector is available for future expansion. Presently, industries in the SIA generate approximately 204,000 t of solid waste. With future development in the industries in the SIA, the estimated quantities will reach 240,000 t. The Shuaiba Area Authority (SAA), a governmental regulatory body responsible for planning and development in the SIA, has recognized the problem of solid waste and has developed an industrial waste minimization program. This program would help to reduce the quantity of waste generated within the SIA and thereby reduce the cost of waste management. This paper presents a description of the waste minimization program and how it is to be implemented by major petroleum companies. The protocols employed in the waste minimization program are detailed.

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