Search results for: moment magnitude

Authors: S. Mogili, J. S. Kuang, N. Zhang

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Knee joints, the beam column connections found at the roof level of a moment resisting frame buildings, are inherently different from conventional interior and exterior beam column connections in the way that forces from adjoining members are transferred into joint and then resisted by the joint. A knee connection has two distinct load resisting mechanisms, each for closing and opening actions acting simultaneously under reversed cyclic loading. In spite of many distinct differences in the behaviour of shear resistance in knee joints, there are no special design provisions in the major design codes available across the world due to lack of in-depth research on the knee connections. To understand the relative importance of opening and closing actions in design, it is imperative to study knee joints under varying shear stresses, especially at higher opening-to-closing shear stress ratios. Three knee joint specimens, under different input shear stresses, were designed to produce a varying ratio of input opening to closing shear stresses. The design was carried out in such a way that the ratio of flexural strength of beams with consideration of axial forces in opening to closing actions are maintained at 0.5, 0.7, and 1.0, thereby resulting in the required variation of opening to closing joint shear stress ratios among the specimens. The behaviour of these specimens was then carefully studied in terms of closing and opening capacities, hysteretic behaviour, and envelope curves to understand the differences in joint performance based on which an attempt to suggest design guidelines for knee joints is made emphasizing the relative importance of opening and closing actions. Specimens with relatively higher opening stresses were observed to be more vulnerable under the action of seismic loading.

Keywords: Knee-joints, large-scale testing, opening and closing shear stresses, seismic performance

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Authors: Larry Turkish

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Introduction: The NBA is an example of mediocrity and this will be evident in the following paper. The study examines and evaluates the characteristics of the NBA champions. As divisions and playoff teams increase, there is an increase in the probability that the champion originates from the mediocre category. Since it’s inception in 1947, the league has been mediocre and continues to this day. Why does a professional league allow any team with a less than 50% winning percentage into the playoffs? As long as the finances flow into the league, owners will not change the current algorithm. The objective of this paper is to determine if the regular season has meaning in finding an NBA champion. Statistical Analysis: The data originates from the NBA website. The following variables are part of the statistical analysis: Rank, the rank of a team relative to other teams in the league based on the regular season win-loss record; Winning Percentage of a team based on the regular season; Divisions, the number of divisions within the league and Playoff Teams, the number of playoff teams relative to a particular season. The following statistical applications are applied to the data: Pearson Product-Moment Correlation, Analysis of Variance, Factor and Regression analysis. Conclusion: The results indicate that the divisional structure and number of playoff teams results in a negative effect on the winning percentage of playoff teams. It also prevents teams with higher winning percentages from accessing the playoffs. Recommendations: 1. Teams that have a winning percentage greater than 1 standard deviation from the mean from the regular season will have access to playoffs. (Eliminates mediocre teams.) 2. Eliminate Divisions (Eliminates weaker teams from access to playoffs.) 3. Eliminate Conferences (Eliminates weaker teams from access to the playoffs.) 4. Have a balanced regular season schedule, (Reduces the number of regular season games, creates equilibrium, reduces bias) that will reduce the need for load management.

Keywords: alignment, mediocrity, regression, z-score

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Authors: Andres Bautista, Alicia Porras, Juan P. Casas, Maribel Silva

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The Colombian aeronautical industry has stimulated research in the mechanical behavior of materials under different loading conditions aircrafts are generally exposed during its operation. The Calima T-90 is the first military aircraft built in the country, used for primary flight training of Colombian Air Force Pilots, therefore, it may be exposed to adverse operating situations such as hard landings which cause impact loads on the aircraft that might produce the impact fatigue phenomenon. The Calima T-90 structure is mainly manufactured by composites materials generating assemblies and subassemblies of different components of it. The main method of bonding these components is by using adhesive joints. Each type of adhesive bond must be studied on its own since its performance depends on the conditions of the manufacturing process and operating characteristics. This study aims to characterize the typical adhesive joints of the aircraft under usual loads. To this purpose, the evaluation of the effect of adhesive thickness on the mechanical performance of the joint under quasi-static loading conditions, constant amplitude fatigue and cyclic impact fatigue using single lap-joint specimens will be performed. Additionally, using a double cantilever beam specimen, the influence of the thickness of the adhesive on the crack growth rate for mode I delamination failure, as a function of the critical energy release rate will be determined. Finally, an analysis of the fracture surface of the test specimens considering the mechanical interaction between the substrate (composite) and the adhesive, provide insights into the magnitude of the damage, the type of failure mechanism that occurs and its correlation with the way crack propagates under the proposed loading conditions.

Keywords: adhesive, composites, crack propagation, fatigue

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Authors: Gulyas Erzsebet

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The multimerisation of proteins is a common feature of many cellular processes; however, it could also impair protein functions and/or be associated with the occurrence of diseases. Thus, development of a research tool monitoring the appearance/presence of multimeric protein forms has great importance for a variety of research fields. Such a tool is potentially applicable in the ante-mortem diagnosis of certain conformational diseases, such as transmissible spongiform encephalopathies (TSE) and Alzheimer’s disease. These conditions are accompanied by the appearance of aggregated protein multimers, present in low concentrations in various tissues. This detection is particularly relevant for TSE where the handling of tissues derived from affected individuals and of meat products of infected animals have become an enormous health concern. Here we demonstrate the potential of such a multimer detection approach in TSE by developing a facile approach. The Biospiral-Detect system resembles a traditional sandwich ELISA, except that the capturing antibody that is attached to a solid surface and the detecting antibody is directed against the same or overlapping epitopes. As a consequence, the capturing antibody shields the epitope on the captured monomer from reacting with the detecting antibody, therefore monomers are not detected. Thus, MDS is capable of detecting only protein multimers with high specificity. We developed an alternative system as well, where RNA aptamers were employed instead of monoclonal antibodies. In order to minimize degradation, the 3' and 5' ends of the aptamer contained deoxyribonucleotides and phosphorothioate linkages. When compared the monoclonal antibodies-based system with the aptamers-based one, the former proved to be superior. Thus all subsequent experiments were conducted by employing the Biospiral -Detect modified sandwich ELISA kit. Our approach showed an order of magnitude higher sensitivity toward mulimers than monomers suggesting that this approach may become a valuable diagnostic tool for conformational diseases that are accompanied by multimerization.

Keywords: diagnosis, ELISA, Prion, TSE

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Authors: Fang Li, Xie-Yuan Yin, Xie-Zhen Yin

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Instability and breakup of electrified viscoelastic liquid jets are involved in various applications such as inkjet printing, fuel atomization, the pharmaceutical industry, electrospraying, and electrospinning. Studying on the instability of electrified viscoelastic liquid jets is of theoretical and practical significance. We built a one-dimensional electrified viscoelastic model to study the nonlinear instability behavior of a perfecting conducting, slightly viscoelastic liquid jet under a radial electric field. The model is solved numerically by using an implicit finite difference scheme together with a boundary element method. It is found that under a radial electric field a viscoelastic liquid jet still evolves into a beads-on-string structure with a thin filament connecting two adjacent droplets as in the absence of an electric field. A radial electric field exhibits limited influence on the decay of the filament thickness in the nonlinear evolution process of a viscoelastic jet, in contrast to its great enhancing effect on the linear instability of the jet. On the other hand, a radial electric field can induce axial non-uniformity of the first normal stress difference within the filament. Particularly, the magnitude of the first normal stress difference near the midpoint of the filament can be greatly decreased by a radial electric field. Decreasing the extensional stress by a radial electric field may found applications in spraying, spinning, liquid bridges and others. In addition, the effect of a radial electric field on the formation of satellite droplets is investigated on the parametric plane of the dimensionless wave number and the electrical Bond number. It is found that satellite droplets may be formed for a larger axial wave number at a larger radial electric field. The present study helps us gain insight into the nonlinear instability characteristics of electrified viscoelastic liquid jets.

Keywords: non linear instability, one-dimensional models, radial electric fields, viscoelastic liquid jets

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Authors: Lana Horvat Dmitrović

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The main purpose of this paper is to study the box dimension as fractal property of bifurcations of discrete dynamical systems in higher dimensions. The paper contains the fractal analysis of the orbits near the hyperbolic and non-hyperbolic fixed points in discrete dynamical systems. It is already known that in one-dimensional case the orbit near the hyperbolic fixed point has the box dimension equal to zero. On the other hand, the orbit near the non-hyperbolic fixed point has strictly positive box dimension which is connected to the non-degeneracy condition of certain bifurcation. One of the main results in this paper is the generalisation of results about box dimension near the hyperbolic and non-hyperbolic fixed points to higher dimensions. In the process of determining box dimension, the restriction of systems to stable, unstable and center manifolds, Lipschitz property of box dimension and the notion of projective box dimension are used. The analysis of the bifurcations in higher dimensions with one multiplier on the unit circle is done by using the normal forms on one-dimensional center manifolds. This specific change in box dimension of an orbit at the moment of bifurcation has already been explored for some bifurcations in one and two dimensions. It was shown that specific values of box dimension are connected to appropriate bifurcations such as fold, flip, cusp or Neimark-Sacker bifurcation. This paper further explores this connection of box dimension as fractal property to some specific bifurcations in higher dimensions, such as fold-flip and flip-Neimark-Sacker. Furthermore, the application of the results to the unit time map of continuous dynamical system near hyperbolic and non-hyperbolic singularities is presented. In that way, box dimensions which are specific for certain bifurcations of continuous systems can be obtained. The approach to bifurcation analysis by using the box dimension as specific fractal property of orbits can lead to better understanding of bifurcation phenomenon. It could also be useful in detecting the existence or nonexistence of bifurcations of discrete and continuous dynamical systems.

Keywords: bifurcation, box dimension, invariant manifold, orbit near fixed point

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Authors: Eric Muñoz de la Torre, Julián González Trinidad, Efrén González Ramírez

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Rain varies greatly in its duration, intensity, and spatial coverage, it is important to have sub-daily rainfall data for various applications, including risk prevention. However, the ground measurements are limited by the low and irregular density of rain gauges. An alternative to this problem are the Satellite Precipitation Products (SPPs) that use passive microwave and infrared sensors to estimate rainfall, as IMERG, however, these SPPs have to be validated before their application. The aim of this study is to evaluate the performance of the IMERG: Integrated Multi-satellitE Retrievals for Global Precipitation Measurament final run V06B SPP in a semi-arid region of Mexico, using 4 automatic rain gauges (pluviographs) sub-daily data of October 2019 and June to September 2021, using the Minimum inter-event Time (MIT) criterion to separate unique rain events with a dry period of 10 hrs. for the purpose of evaluating the rainfall properties (depth, duration and intensity). Point to pixel analysis, continuous, categorical, and volumetric statistical metrics were used. Results show that IMERG is capable to estimate the rainfall depth with a slight overestimation but is unable to identify the real duration and intensity of the rain events, showing large overestimations and underestimations, respectively. The study zone presented 80 to 85 % of convective rain events, the rest were stratiform rain events, classified by the depth magnitude variation of IMERG pixels and pluviographs. IMERG showed poorer performance at detecting the first ones but had a good performance at estimating stratiform rain events that are originated by Cold Fronts.

Keywords: IMERG, rainfall, rain gauge, remote sensing, statistical evaluation

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Authors: Mariana Anaya Villafana

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The sudden change of a significant percentage of the Latino community in the United States elections towards a Republican political orientation was reflected during the 2016 presidential election. This moment represented a radical change that is happening inside the Latino community in the United States, the support they have given to Trump's campaign only demonstrates their support for new anti-immigration regulations and conservative values, which are causing a division of ideologies inside the Latino community. One of the main goals of the following research is to understand the whole phenomenon 'Why would people join their own oppressor?' Align themselves with the politics that prevent many of their relatives to come to the United States and made the assimilation process difficult for their parents. It is important to prove that a change in the identity has happened, through the use of power relations and the attachment to the desired object. A group of Hispanics/Latinos have decided to vote for Trump in order to belong to a society that hasn’t been able to fully include them within it, an action that can result on the non-intentional harm of the values and aims of the rest of the Latino/Hispanic community. In order to understand their new political beliefs, it is necessary to use the method of discourse analysis to comprehend those comments and interviews that are published on web sites such as: 'Latinos for Trump' and 'GOP Hispanic Division'. Among the results that the research has shown, the notion of the 'American Dream' can be considered as a determinant object for the construction of a new identity that is rooted in hard work and legality. One that is proud of the Latino heritage but still wants to maintain the boundaries between legality and illegality in relation to the immigrants. This discourse results on a contradiction to most of the cases because they mention that their families came to the U.S. as immigrants; the only difference is that they work hard to obtain legal citizenship.

Keywords: populism, identity, Latino Community, migration

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Authors: S. K. Hashemi, M. A. Bradford, H. R. Valipour

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The Recent collapse of bridges has raised the awareness about safety and robustness of bridges subjected to extreme loading scenarios such as intentional/unintentional blast loads. The air blast generated by the explosion of bombs or fuel tankers leads to high-magnitude short-duration loading scenarios that can cause severe structural damage and loss of critical structural members. Hence, more attentions need to put towards bridge structures to develop guidelines to increase the resistance of such structures against the probable blast. Recent advancements in numerical methods have brought about the viable and cost effective facilities to simulate complicated blast scenarios and subsequently provide useful reference for safeguarding design of critical infrastructures. In the previous studies common bridge responses to blast load, the traffic load is sometimes not included in the analysis. Including traffic load will increase the axial compression in bridge piers especially when the axial load is relatively small. Traffic load also can reduce the uplift of girders and deck when the bridge experiences under deck explosion. For more complicated structures like cable-stayed or suspension bridges, however, the effect of traffic loads can be completely different. The tension in the cables increase and progressive collapse is likely to happen while traffic loads exist. Accordingly, this study is an attempt to simulate the effect of traffic load cases on the maximum local and global response of an entire cable-stayed bridge subjected to blast loadings using LS-DYNA explicit finite element code. The blast loads ranged from small to large explosion placed at different positions above the deck. Furthermore, the variation of the traffic load factor in the load combination and its effect on the dynamic response of the bridge under blast load is investigated.

Keywords: blast, cable-stayed bridge, LS-DYNA, numerical, traffic load

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Authors: Sepinoud Hamedi

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The ponder points to observationally look at the impact of carbon-neutrality approaches on the key assets required for Industry 4.0 driven savvy fabricating and how these assets can give a economical competitive advantage. The hypothetical system is coordinates with the regulation hypothesis and the resource-based see (RBV). The observational strategy is utilized for collecting information through studies and assist covariance-based auxiliary condition modeling is utilized to test the theories. Discoveries demonstrate that carbon–neutral-based government arrangements have a more grounded impact on unmistakable assets and human aptitudes than intangible assets related to Industry 4.0 driven shrewd fabricating. Moment, carbon–neutral arrangement arrangement with the firm’s maintainability destinations plays a directing impact on the relationship between carbon–neutral-based government arrangements and assets (substantial, intangible assets and human abilities) for Industry 4.0 driven shrewd fabricating. Finally, the three assets (substantial, intangible assets and human abilities) for Industry 4.0 driven savvy fabricating play a basic part in creating firms’ carbon–neutral capability and assist improving operational execution. Administrative suggestions incorporate venture in progressed advanced innovations, creating a solid mentality among workers and supply chain partners, and planning preparing programs for upgrading shrewd fabricating execution to create carbon-neutrality capability. This think about proposes a crossover hypothesis within the setting of carbon nonpartisanship by coordination institutional theory and RBV. Typically the primary think about that looks at the impact of carbon neutrality-based government arrangements on crucial Industry 4.0-driven savvy fabricating assets and the circuitous impact on carbon nonpartisanship capability and operational execution.

Keywords: carbon, industry 4.0, neutrality, RBV, nonpartisanship

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Authors: Abiodun O. Ibude

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Several organizations have devised the strategy of engaging the services of staff not directly employed by them in their production and service delivery. Some organizations also engage on contracting another organization to carry out a part of service or production process on their behalf. Outsourcing is becoming an important alternative employment option for most organizations. This paper attempts an exposition on the rights of workers within the more specific context of outsourcing as a human resource management phenomenon. Outsourced employees and their rights are treated conceptually and analytically in a generic sense as a mere subset of the larger whole, that is, labor. Outsourced employees derive their rights, like all workers, from their job context as well as the legal environment (municipal and global) in which they operate. The dynamics of globalization and the implications of this development for labor practices receive considerable attention in this exposition. In this regard, a guarded proposition is made, to examine the practice and effect of engaging outsourcing as an economic decision designed primarily to cut down on operational costs rather than a Human Resources Management decision to improve worker welfare. The population of the study was selected from purposive and simple random sampling techniques. Data obtained were analyzed through a simple percentage, Pearson product-moment correlation, and cross-tabulation. From the research conducted, it was discovered that, although outsourcing possesses opportunities for organizations, there are drawbacks arising from its implementation of job securities. It was also discovered that some employees are being exploited through this strategy. This gives rise to lower motivation and thereby decline in performance. In conclusion, there is need for examination of Human Resource Managers’ strategies that can serve as management policy tools for the protection of the rights of outsourced employees.

Keywords: legal environment, operational cost, outsourcing, protection

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Authors: Mubarak Suliman, Mohamed Hassan

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Detection of downed conductors occurring with high fault resistance (reaching kilo-ohms) has always been a challenge, especially in countries like Saudi Arabia, on which earth resistivity is very high in general (reaching more than 1000 Ω-meter). The new approaches for the detection of resistive and high impedance faults are based on the analysis of the fault current waveform. These methods are still under research and development, and they are currently lacking security and dependability. The other approach is communication-based solutions which depends on voltage measurement at the end of overhead line branches and communicate the measured signals to substation feeder relay or a central control center. However, such a detection method is costly and depends on the availability of communication medium and infrastructure. The main objective of this research is to utilize the available standard protection schemes to increase the probability of detection of downed conductors occurring with a low magnitude of fault currents and at the same time avoiding unwanted tripping in healthy conditions and feeders. By specifying the operating region of the faulty feeder, use of tripping curve for discrimination between faulty and healthy feeders, and with proper selection of core balance current transformer (CBCT) and voltage transformers with fewer measurement errors, it is possible to set the pick-up of sensitive earth fault current to minimum values of few amps (i.e., Pick-up Settings = 3 A or 4 A, …) for the detection of earth faults with fault resistance more than (1 - 2 kΩ) for 13.8kV overhead network and more than (3-4) kΩ fault resistance in 33kV overhead network. By implementation of the outcomes of this study, the probability of detection of downed conductors is increased by the utilization of existing schemes (i.e., Directional Sensitive Earth Fault Protection).

Keywords: sensitive earth fault, zero sequence current, grounded system, resistive fault detection, healthy feeder

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Authors: Aihong Zhao, Priya Sastry, Mark L Field, Mohamad Bashir, Arvind Singh, David Richens

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Objectives: Intramural haematoma (IMH) is one of the pathologies, along with acute aortic dissection, that present as Acute Aortic Syndrome (AAS). Evidence suggests that unlike aortic dissection, some intramural haematomas may regress with medical management. However, intramural haematomas have been traditionally managed like acute aortic dissections. Given that some of these pathologies may regress with conservative management, it would be useful to be able to identify which of these may not need high risk emergency intervention. A computational aortic model was used in this study to try and identify intramural haematomas with risk of progression to aortic dissection. Methods: We created a computational model of the aorta with luminal blood flow. Reports in the literature have identified 11 mm as the radial clot thickness that is associated with heightened risk of progression of intramural haematoma. Accordingly, haematomas of varying sizes were implanted in the modeled aortic wall to test this hypothesis. The model was exposed to physiological blood flows and the stresses and strains in each layer of the aortic wall were recorded. Results: Size and shape of clot were seen to affect the magnitude of aortic stresses. The greatest stresses and strains were recorded in the intima of the model. When the haematoma exceeded 10 mm in all dimensions, the stress on the intima reached breaking point. Conclusion: Intramural clot size appears to be a contributory factor affecting aortic wall stress. Our computer simulation corroborates clinical evidence in the literature proposing that IMH diameter greater than 11 mm may be predictive of progression. This preliminary report suggests finite element modelling of the aortic wall may be a useful process by which to examine putative variables important in predicting progression or regression of intramural haematoma.

Keywords: intramural haematoma, acute aortic syndrome, finite element analysis,

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Authors: Nemanja D. Kidzin

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The field of personality change has recently garnered increased attention, while the psychology of acting has remained relatively understudied. This research tried to contribute to the both research field by investigating whether the process of acting can lead to personality changes in acting students and, if so, in what manner. It was hypothesized that significant differences would be observed in self-reported personality traits of acting students between the beginning and end of their role preparation. The study also examined potential moderator variables, including the reported personality traits of the roles portrayed by the students, empathy, disintegration, and years of formal acting education. The sample comprised 47 students of acting from the Faculty of Dramatic Arts (first to fourth-year) and the Faculty of Modern Arts (first-year students only). The research involved two waves of testing, conducted at the beginning (T1) and end (T2) of the semester. Personality traits (measured using the HEXACO-60 self-report version), empathy (measured using the Questionnaire of Cognitive and Affective Empathy, QCAE), and disintegration (measured using the DELTA9, 10-item version) were assessed at both T1 and T2, while the personality of the role (measured using the HEXACO-60 observer version) was assessed at T2. Repeated-measures t-tests revealed significant differences in emotionality and conscientiousness between T1 and T2. Additionally, an index of absolute personality change was significantly different from 0 for all traits, indicating personality change. The average test-retest correlation for HEXACO traits was 0.57, lower than that proposed in similar research. However, the personality of the role, empathy, and disintegration did not explain the changes in students' personality traits as moderator variables. The magnitude of personality change was highest among fourth-year students, with no significant differences observed among the remaining three years of study. Overall, the findings suggest the presence of personality changes or trait variability in acting students. However, these changes cannot be conclusively attributed to the process of role preparation. Further research with more stringent methodologies is needed to better understand the role of acting in personality change.

Keywords: personality change, psychology of acting, empathy, disintegraton

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Authors: Irina Bondarenko, Olga Vandina

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The theory of evolutionary economics is the basis for preparation and application of methods forming the stock market infrastructure development concept. The authors believe that the basis for the process of formation and development of the stock market model infrastructure in Russia is the theory of large systems. This theory considers the financial market infrastructure as a whole on the basis of macroeconomic approach with the further definition of its aims and objectives. Evaluation of the prospects for interaction of securities market institutions will enable identifying the problems associated with the development of this system. The interaction of elements of the stock market infrastructure allows to reduce the costs and time of transactions, thereby freeing up resources of market participants for more efficient operation. Thus, methodology of the transaction analysis allows to determine the financial infrastructure as a set of specialized institutions that form a modern quasi-stable system. The financial infrastructure, based on international standards, should include trading systems, regulatory and supervisory bodies, rating agencies, settlement, clearing and depository organizations. Distribution of financial assets, reducing the magnitude of transaction costs, increased transparency of the market are promising tasks in the solution for questions of services level and quality increase provided by institutions of the securities market financial infrastructure. In order to improve the efficiency of the regulatory system, it is necessary to provide "standards" for all market participants. The development of a clear regulation for the barrier to the stock market entry and exit, provision of conditions for the development and implementation of new laws regulating the activities of participants in the securities market, as well as formulation of proposals aimed at minimizing risks and costs, will enable the achievement of positive results. The latter will be manifested in increasing the level of market participant security and, accordingly, the attractiveness of this market for investors and issuers.

Keywords: institutional infrastructure, financial assets, regulatory system, stock market, transparency of the market

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Authors: I. Székács, Á. Fejes, S. Klátyik, E. Takács, D. Patkó, J. Pomóthy, M. Mörtl, R. Horváth, E. Madarász, B. Darvas, A. Székács

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Environmental and toxicological characteristics of formulated pesticides may substantially differ from those of their active ingredients or other components alone. This phenomenon is demonstrated in the case of the herbicide active ingredient glyphosate. Due to its extensive application, this active ingredient was found in surface and ground water samples collected in Békés County, Hungary, in the concentration range of 0.54–0.98 ng/ml. The occurrence of glyphosate appeared to be somewhat higher at areas under intensive agriculture, industrial activities and public road services, but the compound was detected at areas under organic (ecological) farming or natural grasslands, indicating environmental mobility. Increased toxicity of the formulated herbicide product Roundup, compared to that of glyphosate was observed on the indicator aquatic organism Daphnia magna Straus. Acute LC50 values of Roundup and its formulating adjuvant Polyethoxylated Tallowamine (POEA) exceeded 20 and 3.1 mg/ml, respectively, while that of glyphosate (as isopropyl salt) was found to be substantially lower (690-900 mg/ml) showing good agreement with literature data. Cytotoxicity of Roundup, POEA and glyphosate has been determined on the neuroectodermal cell line, NE-4C measured both by cell viability test and holographic microscopy. Acute toxicity (LC50) of Roundup, POEA and glyphosate on NE-4C cells was found to be 0.013±0.002%, 0.017±0.009% and 6.46±2.25%, respectively (in equivalents of diluted Roundup solution), corresponding to 0.022±0.003 and 53.1±18.5 mg/ml for POEA and glyphosate, respectively, indicating no statistical difference between Roundup and POEA and 2.5 orders of magnitude difference between these and glyphosate. The same order of cellular toxicity seen in average cell area has been indicated under quantitative cell visualization. The results indicate that toxicity of the formulated herbicide is caused by the formulating agent, but in some parameters toxicological synergy occurs between POEA and glyphosate.

Keywords: glyphosate, polyethoxylated tallowamine, Roundup, combined aquatic and cellular toxicity, synergy

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Authors: M. R. Ahmad, I. Musirin, M. M. Othman, N. A. Rahmat

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Plug-in Hybrid-Electric Vehicle (PHEV) has gained immense popularity in recent years. PHEV offers numerous advantages compared to the conventional internal-combustion engine (ICE) vehicle. Millions of PHEVs are estimated to be on the road in the USA by 2020. Uncoordinated PHEV charging is believed to cause severe impacts to the power grid; i.e. feeders, lines and transformers overload and voltage drop. Nevertheless, improper PHEV data model used in such studies may cause the findings of their works is in appropriated. Although smart charging is more attractive to researchers in recent years, its implementation is not yet attainable on the street due to its requirement for physical infrastructure readiness and technology advancement. As the first step, it is finest to study the impact of charging PHEV based on real vehicle travel data from National Household Travel Survey (NHTS) and at present charging rate. Due to the lack of charging station on the street at the moment, charging PHEV at home is the best option and has been considered in this work. This paper proposed a technique that comprehensively presents the impact of charging PHEV on power system networks considering huge numbers of PHEV samples with its traveling data pattern. Vehicles Charging Load Profile (VCLP) is developed and implemented in IEEE 30-bus test system that represents a portion of American Electric Power System (Midwestern US). Normalization technique is used to correspond to real time loads at all buses. Results from the study indicated that charging PHEV using opportunity charging will have significant impacts on power system networks, especially whereas bigger battery capacity (kWh) is used as well as for higher penetration level.

Keywords: plug-in hybrid electric vehicle, transportation electrification, impact of charging PHEV, electricity demand profile, load profile

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Authors: Joseph Clement Akan, Lami Jafiya, Zaynab Muhammad Chellube, Zakari Mohammed, Fanna Inna Abdulrahman

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Five vegetables (spinach, lettuce, cabbage, tomato, and onion) were freshly harvested from the Alau Dam and Gongulong agricultural areas for the determination of some organochlorine pesticide residues (o, p-DDE, p,p’-DDD, o,p’-DDD, p,p’-DDT, α-BHC, γ-BHC, metoxichlor, lindane, endosulfan dieldrin, and aldrin.) Soil samples were also collected at different depths for the determination of the above pesticides. Samples collection and preparation were conducted using standard procedures. The concentrations of all the pesticides in the soil and vegetable samples were determined using GC/MS SHIMADZU (GC-17A) equipped with electron capture detector (ECD). The highest concentration was that of p,p’-DDD (132.4±13.45µg/g) which was observed in the leaf of cabbage, while the lowest concentration was that of p,p’-DDT (2.34µg/g) was observed in the root of spinach. Similar trends were observed at the Gongulong agricultural area, with p,p’-DDD having the highest concentration of 153.23µg/g in the leaf of cabbage, while the lowest concentration was that of p,p’-DDT (12.45µg/g) which was observed in the root of spinach. α-BHC, γ-BHC, Methoxychlor, and lindane were detected in all the vegetable samples studied. The concentrations of all the pesticides in the soil samples were observed to be higher at a depth of 21-30cm, while the lowest concentrations were observed at a depth of 0-10cm. The concentrations of all the pesticides in the vegetables and soil samples from the two agricultural sites were observed to be at alarming levels, much higher than the maximum residue limits (MRLs) and acceptable daily intake values (ADIs) .The levels of the pesticides observed in the vegetables and soil samples investigated, are of such a magnitude that calls for special attention and laws to regulate the use and circulation of such chemicals. Routine monitoring of pesticide residues in these study areas is necessary for the prevention, control and reduction of environmental pollution, so as to minimize health risks.

Keywords: Alau Dam, gongulong, organochlorine, pesticide residues, soil, vegetables

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Authors: Davie Hope Moyo

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The environment is a combination of two things: resources and hazards. One of the hazards that is a result of environmental changes is the occurrence of flooding. Floods are one of the disasters that are highly feared by people because they have a huge impact on the human population and their environment. In recent years, flooding disasters in the Nsanje district are increasing in both frequency and magnitude. This study aims to understand the root causes of this phenomenon. To understand the causes of flooding, this study focused on the case of TA Ndamera in the Nsanje district, southern Malawi. People in the Nsanje district face disruption in their day-to-day life because of floods that affect their communities. When floods happen, people lose their property, land, livestock, and even lives. The study was carried out in order to have a better understanding of the root causes of floods. The findings of this study may help the government and other development agencies to put in place mitigation measures that will make Nsanje District resilient to the occurrence of future flood hazards. Data was collected from the area of TA Ndamera in order to assess the causes of flooding in the district. Interviews, transect walks, and researcher observation was done to appreciate the topography of the district and evaluate other factors that are making the people become vulnerable to the impacts of flooding in the district. It was found that flooding in the district is mainly caused by heavy rainfall in the upper shire, settlements along river banks, deforestation, and the topography of the district in general. The research study ends by providing recommendation strategies that need to be put in place to increase the resilience of the communities to future flood hazards. The research recommends the development of indigenous knowledge systems to alert people of incoming floods, construction of evacuation centers to ease pressure on schools, savings, and insurance schemes, construction of dykes, desilting rivers, and afforestation.

Keywords: disaster causes, mitigation, safety measures, Nsanje Malawi

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Authors: Akbar Jamali

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Many scholars consider Hegel’s philosophy of art as the greatest theory of aesthetics since Aristotle’s Poetics. ‘Freedom’ distinguishes modern, especially German Idealism with Greek philosophy. Therefore, introducing and contemplating on Hegel’s Aesthetics as a whole, freedom as the essence of art, Hegel’s controversial claim on the end of art, and the relation of art and state is the main theme of this study. Hegel’s aesthetics is to be understood in his whole system. According to Hegel’s speculative philosophy, being is to be understood as self-determining Reason or Idea. The self-determining Reason actualizes and realizes himself in the course of history. Idea in the process of self-actualization becomes more and more rational. It first actualizes itself in matter, then in non-conscious life, finally in conscious and self-conscious life. Self-conscious life is the most rational stage of development of Idea in which the subject can think and imagine, use language and exercise freedom. Hegel calls this self-conscious life Spirit (Geist). Therefore, emergence of human being is an essential moment in the process of self-determination of Reason. It is not accidental rather a necessity. The essence of spirit is freedom. Since the history is the process of the self-actualization if spirit, humankind becomes more and more, free. Spirit in its ‘Absolute’ form manifests itself into three forms; Art, Religion and philosophy. Art is the first stage in which Spirit understands itself. In fact, Art is the expression of human spirit, which is comprehended by our senses. Beauty is defined as the sensuous expression of free Spirit. The purpose of art is, therefore, to express, enjoy and contemplate on our freedom. State belongs to the realm of Objective spirit, while Art along with Religion and philosophy belong to the realm of Absolute Spirit. Absolute spirit is superior to Objective Spirit; therefore, state must not interfere in the realm of art. Limitation on art by state directly violates freedom and prevents development of national spirit. Genuine art leads us to freedom and richness of (national) Spirit. Using Hegel’s philosophy of art, we can comprehend why totalitarian states try to limit art and, why artists are the enemy of totalitarian states. In this philosophical system, we contemplate on art as a way to freedom and emancipation.

Keywords: aesthetics, freedom, spirit, state

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Authors: Salma I. Dwidar, Amal A. Abdelsattar

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Alexandria city is one of the greatest cities in the world. It confronted different civilizations throughout the ages due to its special geographical location and climate which left many archaeological areas of great heritage (Ptolemaic, Greek, Romanian, especially sunken monuments, Coptic, Islamic, and finally, the Modern). Also, Alexandria city contains areas with different patterns of urban planning, both Hellenistic and compacted planning which merited the diversity in planning. Despite the magnitude of this city, which contains all the elements of tourism, the city was not included in the tourism map of Egypt properly comparing with similar cities in Egypt. This paper discusses the importance of heritage areas in Alexandria and the relationship between heritage areas and modern buildings. It highlights the absence of a methodology to deal with heritage areas as touristic areas. Also, the paper aims to develop multiple touristic routes to visit archaeological areas and other sights of significance in Alexandria. The research methodology is divided into two main frameworks. The first framework is a historical study of the urban development of Alexandria and the most important remaining monuments throughout the ages, as well as an analytical study of sunken monuments and their importance in increasing the rate of tourism. Moreover, it covers a study of the importance of the Library of Alexandria and its effect on the international focus of the city. The second framework focuses on the proposal of some tourism routes to visit the heritage areas, archaeological monuments, sunken monuments and the sights of Alexandria. The study concludes with the proposal of three tourism routes. The first route, which is the longest one, passes by all the famous monuments of the city as well as its modern sights. The second route passes through the heritage areas, sunken monuments, and Library of Alexandria. The third route includes the sunken monuments and Library of Alexandria. These three tourism routes will ensures the touristic development of the city which leads to the economic growth of the city and the country.

Keywords: archeological buildings, heritage buildings, heritage tourism, planning of Islamic cities

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Authors: Ayesha Siddiqua

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Background: Hypertension is a silent killer disease and a common risk factor for considerable morbidity and mortality. Its effects can be seen on the organs like Heart; Brain; Kidneys. In Saudi Arabia, hypertension affects a sizeable enough proportion of the population, with a prevalence of 27.9% in urban and 22.4 in rural population. Despite these features, the magnitude and epidemiological characteristics of this disease have been rarely studied in Saudi Arabia. To fill this gap, we conducted a survey in Abha to study the KAP of hypertension. KAP study shows what people know about certain things, their feelings and behavior towards the disease management. An improvement in the Knowledge and Attitudes towards disease management can reform the kinds of practices which are followed. Objectives: To assess the level of Knowledge, Attitude and Practice of patients who suffer from Hypertension. To improve the Quality of life of patients. Methods: A prospective cross-sectional survey was conducted on a sample size of 130 Hypertensive patients of both the genders enrolled by simple random sampling technique admitted in the Aseer Central Hospital of Abha during the period from October 2016 to December 2016. Results: Altogether 130 hypertensive patients were enrolled in this study with equal no. of Males and Females. Most of the respondents were aged between 18-40 years (45%). On assessing the KAP of the patients, we found that the Knowledge and Attitude score was good but the Practice scores were moderate in both the genders. Conclusion: Our study concludes that a significant proportion of hypertensive patients show less Practice towards the disease management which can lead to severe complications in time being and also result in damage of other vital organs. So there is a need of intense educational intervention for the patients which can be done by Patient counselling by the clinical pharmacist. Strategies to modify lifestyle which help in control of hypertension can include providing leaflets as well as direct educational programs.

Keywords: Attitude, hypertension, Knowledge, practices

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Authors: Juan Carlos Aguirre Pabon, Stephen Sabatino, James Morris, Khor Waiho, Antonio Murias

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The tiger shrimp Penaeus monodon is one of the most important species in aquaculture and is native to the Indo-Pacific Ocean. During its greatest success in world production (70s and 80s) was introduced in many Atlantic Ocean countries for cultivation purposes and is currently reported as established in several countries of this area. Because there are no studies to understand the magnitude of the invasion process, this is an exciting opportunity to test evolutionary hypotheses in the context of marine invasions mediated by culture systems; therefore, the purpose of this study was to reconstruct the scenario of invasion of P. monodon in the Atlantic Ocean, by using mitochondrial DNA and eight loci microsatellites. In addition, samples of the invasion area in the Atlantic Ocean (US, Colombia, Venezuela, Brazil, Guienne Bissau, Senegal), the Indo-Pacific Ocean (Indonesia, India, Mozambique), and some cultivation systems (India, Bangladesh, Madagascar) were collected; and analysis of phylogenetic relationships (using some species of the family), genetic diversity, structure population, and demographic changes were performed. High intraspecific divergence in P. semisulcatus and P. monodon were found, high genetic variability in all sites (especially with microsatellites) and the presence of three clusters or populations. In addition, signs of demographic expansion in the culture population and bottlenecks in the invasive and native populations were found, as well as evidence of gene mixtures from all of the populations studied, implying that cropping systems play an essential role in mitigating the negative effects of the founder effect and providing a source of genetic variability that can ensure the success of the invasion.

Keywords: species introduction, increased variability, demographic changes, promoting invasion.

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Authors: Tahar Tayachi, Ahlam Alrehaili

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Purpose: The purpose of this paper is to investigate the relationship between the corporate board characteristics and the dividend policy among firms on the Saudi Stock Exchange. Design/Methodology/Approach: This paper uses a sample of 103 nonfinancial firms over a time period of 4 years from 2015 to 2018. To investigate how corporate governance mechanisms such as board independence, the board size, frequency of meetings, and free cash flow impact dividends, the study uses Logit and Tobit models. Findings: This paper finds that board size, board independence, and frequency of board meetings have no influence on a firm’s decision to pay dividends, while board size has a significantly positive impact on the levels of cash dividends paid to investors. This study also finds that the level of free cash flows has a positively significant influence on both the decision to pay dividends and the magnitude of dividend payouts. Research Limitations/Implications: This paper attempts to study the effectiveness of dividend policy among some firms on the Saudi Stock Exchange. Practical Implications: The findings reveal that board characteristics, which represent one of the crucial mechanisms of corporate governance, were found to be complementary to corporate laws and regulations imposed on the Saudi market in 2015. The findings also imply that capital market authorities should revise their corporate regulations and ensure that protection laws are adequate and strong enough to protect the interests of all shareholders. Originality/Value: This paper is among the few studies focusing on dividend policy in Saudi Arabia. Finally, these findings suggest that the improvements in corporate laws in Saudi Arabia led to such an outcome, and it has become prevalent in dividend policy decisions and behaviors of Saudi firms.

Keywords: agency theory, Tobit, corporate governance, dividend payout, Logit

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Authors: Vidula Shevade, B. J. Nagare, Sajeev Chacko

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First principles simulation, meaning density functional theory (DFT) calculations with plane waves and pseudopotential, has become a prized technique in condensed matter theory. Nanoparticles (NP) have been known to possess good catalytic activities, especially for molecules such as CO, O₂, etc. Among the metal NPs, Aluminium based NPs are also widely known for their catalytic properties. Aluminium metal is a lightweight, excellent electrical, and thermal abundant chemical element in the earth’s crust. Aluminium NPs, when added to solid rocket fuel, help improve the combustion speed and considerably increase combustion heat and combustion stability. Adding aluminium NPs into normal Al/Al₂O₃ powder improves the sintering processes of the ceramics, with high heat transfer performance, increased density, and enhanced thermal conductivity of the sinter. We used VASP and Gaussian 0₃ package to compute the geometries, electronic structure, and bonding properties of Al₁₂Ni as well as its interaction with O₂ and CO molecules. Several MD simulations were carried out using VASP at various temperatures from which hundreds of structures were optimized, leading to 24 unique structures. These structures were then further optimized through a Gaussian package. The lowest energy structure of Al₁₂Ni has been reported to be a singlet. However, through our extensive search, we found a triplet state to be lower in energy. In our structure, the Ni atom is found to be on the surface, which gives the non-zero magnetic moment. Incidentally, O2 and CO molecules are also triplet in nature, due to which the Al₁₂-Ni cluster is likely to facilitate the oxidation process of the CO molecule. Our results show that the most favourable site for the CO molecule is the Ni atom and that for the O₂ molecule is the Al atom that is nearest to the Ni atom. Al₁₂Ni-O₂ and Al₁₂-Ni-CO structures we extracted using VMD. Al₁₂Ni nanocluster, due to in triplet electronic structure configuration, indicates it to be a potential candidate as a catalyst for oxidation of CO molecules.

Keywords: catalyst, gaussian, nanoparticles, oxidation

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Authors: Ndarusanze Berchmans

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This research work focused on the analysis of the observations of tuberculous meningitis in HIV-positive patients who were treated by the Prince Regent Charles Hospital in Bujumbura. A number of 246 seropositive patients were examined by the laboratory of Prince Regent Charles in the period between 2010 and 2015. We did a retrospective study; we used data from the registers of the laboratories mentioned above; the objective was to approach the epidemiological, biological, clinical, and therapeutic characteristics of tuberculosis meningitis infection: 124 women (50.40% of AIDS patients) and 122 men (49.59% of AIDS patients) were subject to the diagnosis by identification of cerebrospinal fluid (CSF). The average age of the patients was 30 years for this period. The population at risk has an average age of between 34 and 42 years for the years between 2010-2015. From 2010 to 2012, cases of opportunistic diseases (e.g., tuberculous meningitis and Cryptococcus neoformans meningitis), often found in immunocompromised, were observed at a high rate; in this period, there was a disturbance of the rhythm providing antiretroviral drugs to people with AIDS. The rate of the two meningitis (tuberculous meningitis and Cryptococcus neoformans meningitis) remained above 10% to gradually decrease until 2015, with the gradual return of antiretrovirals. This period records an overall average of 25 cases of tuberculous meningitis, or a percentage of 10.16%. For the year 2015, there were 4 cases of tuberculous meningitis out of a total of 35 seropositive examined (11.42%). This year's percentage shows that the number of tuberculous meningitis cases has fallen from the rate in previous years. This is the result of the care given by associations against HIV/AIDS to HIV-positive people. This decrease in cases of tuberculous meningitis is due to the acquisition of antiretrovirals by all HIV-positive people treated by hospitals. For the moment, these hospitals are taking care of many AIDS patients by providing them permanently with antiretrovirals; Besides that, there are many patients who are supported by associations whose activities are directed against HIV/AIDS.

Keywords: Cryptococcus neoformans meningitis, tuberculosis meningitis, neurological complications, epidemiology of meningitis

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Authors: Muhammad R. Bello, Mamman A. Wasagu, Yahya M. Kamar

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The study investigated the effects of computer-aided instructional package (CAIP) on performance and retention of genetic concepts among secondary school students in Niger State. Quasi-experimental research design i.e. pre-test-post-test experimental and control groups were adopted for the study. The population of the study was all senior secondary school three (SS3) students’ offering biology. A sample of 223 students was randomly drawn from six purposively selected secondary schools. The researchers’ developed computer aided instructional package (CAIP) on genetic concepts was used as treatment instrument for the experimental group while the control group was exposed to the conventional lecture method (CLM). The instrument for data collection was a Genetic Performance Test (GEPET) that had 50 multiple-choice questions which were validated by science educators. A Reliability coefficient of 0.92 was obtained for GEPET using Pearson Product Moment Correlation (PPMC). The data collected were analyzed using IBM SPSS Version 20 package for computation of Means, Standard deviation, t-test, and analysis of covariance (ANCOVA). The ANOVA analysis (Fcal (220) = 27.147, P < 0.05) shows that students who received instruction with CAIP outperformed the students who received instruction with CLM and also had higher retention. The findings also revealed no significant difference in performance and retention between male and female students (tcal (103) = -1.429, P > 0.05). It was recommended amongst others that teachers should use computer-aided instructional package in teaching genetic concepts in order to improve students’ performance and retention in biology subject. Keywords: Computer-aided Instructional Package, Performance, Retention and Genetic Concepts.

Keywords: computer aided instructional package, performance, retention, genetic concepts, senior secondary school students

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Authors: Tom Hickey

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It is difficult to conceive of a case that might more starkly bring the arguments concerning judicial review to the fore than State (Ryan) v Lennon. Small wonder that it has attracted so much scholarly attention, although the fact that almost all of it has been in an Irish setting is perhaps surprising, given the illustrative value of the case in respect of a philosophical quandary that continues to command attention in all developed constitutional democracies. Should judges have power to invalidate legislation? This article revisits Ryan v Lennon with an eye on the importance of the idea of “democracy” in the case. It assesses the meaning of democracy: what its purpose might be and what practical implications might follow, specifically in respect of judicial review. Based on this assessment, it argues for a particular institutional model for the vindication of constitutional rights. In the context of calls for the drafting of a new constitution for Ireland, however forlorn these calls might be for the moment, it makes a broad and general case for the abandonment of judicial supremacy and for the taking up of a model in which judges have a constrained rights reviewing role that informs a more robust role that legislators would play, thereby enhancing the quality of the control that citizens have over their own laws. The article is in three parts. Part I assesses the exercise of judicial power over legislation in Ireland, with the primary emphasis on Ryan v Lennon. It considers the role played by the idea of democracy in that case and relates it to certain apparently intractable dilemmas that emerged in later Irish constitutional jurisprudence. Part II considers the concept of democracy more generally, with an eye on overall implications for judicial power. It argues for an account of democracy based on the idea of equally shared popular control over government. Part III assesses how this understanding might inform a new constitutional arrangement in the Irish setting for the vindication of fundamental rights.

Keywords: constitutional rights, democracy as popular control, Ireland, judicial power, republican theory, Ryan v Lennon

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Authors: Gelacio JuáRez-Luna, Daniel Enrique GonzáLez-RamíRez, Enrique Tenorio-Montero

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Frame elements coupled with springs elements are used for modelling the development of hinges in segmented tunnels, the spring elements modelled the rotational, transversal and axial failure. These spring elements are equipped with constitutive models to include independently the moment, shear force and axial force, respectively. These constitutive models are formulated based on damage mechanics and experimental test reported in the literature review. The mesh of the segmented tunnels was discretized in the software GID, and the nonlinear analyses were carried out in the finite element software ANSYS. These analyses provide the capacity curve of the primary and secondary lining of a segmented tunnel. Two numerical examples of segmented tunnels show the capability of the spring elements to release energy by the development of hinges. The first example is a segmental concrete lining discretized with frame elements loaded until hinges occurred in the lining. The second example is a tunnel with primary and secondary lining, discretized with a double ring frame model. The outer ring simulates the segmental concrete lining and the inner ring simulates the secondary cast-in-place concrete lining. Spring elements also modelled the joints between the segments in the circumferential direction and the ring joints, which connect parallel adjacent rings. The computed load vs displacement curves are congruent with numerical and experimental results reported in the literature review. It is shown that the modelling of a tunnel with primary and secondary lining with frame elements and springs provides reasonable results and save computational cost, comparing with 2D or 3D models equipped with smeared crack models.

Keywords: damage, hinges, lining, tunnel

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Authors: Jingcheng Ma, Patricia B. Weisensee, Young H. Shin, Yujin Chang, Junjiao Tian, William P. King, Nenad Miljkovic

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Water droplet impact on surfaces is a ubiquitous phenomenon in both nature and industry. The transfer of mass, momentum and energy can be influenced by the time of contact between droplet and surface. In order to reduce the contact time, we study the influence of substrate motion prior to impact on the dynamics of droplet recoil. Using optical high speed imaging, we investigated the impact dynamics of macroscopic water droplets (~ 2mm) on rigid nanostructured superhydrophobic surfaces vibrating at 60 – 300 Hz and amplitudes of 0 – 3 mm. In addition, we studied the influence of the phase of the substrate at the moment of impact on total contact time. We demonstrate that substrate vibration can alter droplet dynamics, and decrease total contact time by as much as 50% compared to impact on stationary rigid superhydrophobic surfaces. Impact analysis revealed that the vibration frequency mainly affected the maximum contact time, while the amplitude of vibration had little direct effect on the contact time. Through mathematical modeling, we show that the oscillation amplitude influences the possibility density function of droplet impact at a given phase, and thus indirectly influences the average contact time. We also observed more vigorous droplet splashing and breakup during impact at larger amplitudes. Through semi-empirical mathematical modeling, we describe the relationship between contact time and vibration frequency, phase, and amplitude of the substrate. We also show that the maximum acceleration during the impact process is better suited as a threshold parameter for the onset of splashing than a Weber-number criterion. This study not only provides new insights into droplet impact physics on vibrating surfaces, but develops guidelines for the rational design of surfaces to achieve controllable droplet wetting in applications utilizing vibration.

Keywords: contact time, impact dynamics, oscillation, pear-shape droplet

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