Empirical Power Research Articles

Combat Knife with Eagle-Headed Handle from Cimmerian Bosporos

In the Romano-Germanic Museum in Cologne (Diergardt collection) there is a combat knife originating from Cimmerian Bosporos. Its hilt is decorated with a bronze image of eagle’s head. The purpose of this publication is to call attention to this artifact almost not known to Eastern European archaeologists. The handles of swords decorated with eagle’s heads from the Roman Period are well known primarily from iconographic data. Noteworthy is the image on a silver bowl from Avignon (the so-called “Briseis Cup”) dated to the fourth century. It depicts a weapon with a rather short blade and a U-shaped chape; all these features resemble the Bosporan combat knife. In the Late Roman Period, swords with eagle-headed hilts were well represented in the images of the persons of status, probably indicating their prominent role of a symbol of power. Generally, eagle is well represented among the symbols of power of the Late Empire, for example, on consular rods or shields with the emblems of military units mentioned in the Notitia Dignitatum. In the Late Roman Period, sword hilts featuring bird’s head also occurred outside the Empire. This is evidenced by the image of the Sassanian Shah Shapur II on a plate from Turusheva. In the “chieftain” culture of the Eastern and Central European Barbaricum and the Northern Black Sea Area from the Great Migration Period, the inlaid patterns showing eagle or bird’s heads is well known on weapons, including swords and horse trappings. In the Barbaricum, there probably appeared the well-known phenomenon of imitatio imperii.

Investigation of electrical power consumption of an additive process chain and empirical modelling as feature selection for machine learning algorithms

The focus on the fourth industrial revolution and advancements in 3D printing has reignited the need for energy efficient manufacturing. In particular, Selective Laser Melting (SLM), an additive manufacturing process, has garnered wide attention owing to its adaptability in producing lightweight components for metal industries. Reasonable material demand along with environmental and methodical capabilities of SLM machines has opened up an intriguing possibility to examine its power consumption as well as to determine its suitability for energy efficient manufacturing. In addition, the energy demand of SLM machines along with its occupancy time in a factory floor poses challenges to energy supply grid and subsequent effects on energy flexibility. Hence, it is necessary to determine energy demand of SLM process chain. This paper provides an empirical power consumption analysis of an additive process chain and interprets the power utilized by various process steps of an SLM machine.

An inverse norm weight spatial sign test for high-dimensional directional data

In this paper, we focus on the high-dimensional location testing problem of directional data under the assumption of rotationally symmetric distributions, where the data dimension is potentially much larger than the sample size. We study the family of directional weighted spatial sign tests for this testing problem and establish the asymptotic null distributions and local power properties of this family. In particular, we find that the test based on the inverse norm weight, named as the inverse norm weight spatial sign test, has the maximum asymptotic power in this family. As demonstrated by extensive numerical results, the inverse norm weight spatial sign test has advantages in empirical power compared with some other members in the family as well as some existing tests.

Study on grinding mode effect on external conical thread quality

The article has grounded the necessity to develop an empirical power dependence of cutting modes influence on part surface roughness obtained during thread grinding. The calculations were carried out for grinding of parts made of steel and hard alloy. There have been developed a relation of part material properties, grinding wheel options, lubricating and cooling liquid (constant for concrete conditions of thread grinding), depth of cutting (thickness of a grinded layer per path), revolutions of a part and a wheel, longitudinal feed refer to obtained roughness. It has been stated that components of the grinding mode contribute in roughness values in different way, in particular they are arranged in the ascending order as follows: grinding depth, rotation speed, and detail’s diameter.

Power of Overdispersion Tests in Zero-Truncated Negative Binomial Regression Model

Poisson regression is the most extensively used model for modeling data that are measured as counts. The main characteristic of Poisson regression model is the equidispersion limitation in which the mean and variance of the count variable are the same. However, in many situations the variance of the count variable is greater than the mean which causes overdispersion, and hence, poor fit will be resulted when inference about regression parameters. Alternatively, the negative binomial regression is preferred when overdispersion is present. In addition, in particular cases, the zero counts are not observed in data which is known as zero-truncation. In the presence of overdispersion in zero-truncated count data, the zero-truncated negative binomial (ZTNB) regression model can be used as an alternative to zero-truncated Poisson (ZTP) regression model. In this paper, for testing overdispersion in ZTNB regression model against ZTP regression model, the likelihood ratio test (LRT), score test, and Wald test are proposed. A Monte-Carlo simulation is carried out in order to examine the empirical power for statistics of these tests under different levels of overdispersion and various sample sizes. The simulation results indicate that Wald test is more powerful than the LRT and score test for detecting the overdispersion parameter in ZTNB regression model against ZTP regression model, since it provides the highest statistical power. Thus, the Wald test is preferable for detecting the overdispersion problem in zero-truncated count data.

Laminar flame propagation in nitrogen-diluted stoichiometric H2-N2O mixtures – a numerical study

The paper reports results of the detailed chemical modelling of isobaric deflagrations in stoichiometric H2-N2O-N2 mixtures (N2 = 20 - 60 vol%) at various initial temperatures (300 - 500 K) and various initial pressures (1 - 10 bar): laminar burning velocities, and profiles of temperature, volumetric heat release rate and species concentrations across the flame front. The dependence of the laminar burning velocity on temperature and pressure is examined by empirical power laws, for restricted ranges of pressure (or temperature) variation. For each examined composition, the laminar burning velocity correlates well with the volumetric rate of heat release and with the sum of mass fractions of reactive species in the flame front.

Pakistan as a modern Islamic democracy: The quest between Islamic teachings and modern democratic modes

Democracy is the best form of government in the 21stcentury and West is not accepted any regime just and trustworthy without it. With this reference all colonial power in general and British Empire in particular emphasized the democratic format in all its colonies before giving them independence. Thus, after the creation of Pakistan every effort was made to bridge the Islamic modes and democratic rules in creating constitution for a newly born Islamic state. Starting from objective resolution to 1973 constitution every effort is made on Islamic, political and legal grounds to achieve the task of modern Islamic democracy. This research paper is an effort to understand the relation of both aspects and explain the future prospects of its achievement

Volume Estimation of Landslide Affected Soil Moisture Using TRIGRS: A Case Study of Longxi River Small Watershed in Wenchuan Earthquake Zone, China

After the 2008 Mw 7.9 Wenchuan earthquake, geological hazards occurred frequently in the southwest mountainous watershed. Frequent landslide disasters provide abundant sediment supply for mountain torrent disasters. The estimation of the potential landslide volume is essential for the risk assessment of mountain torrent disasters. In this study, a method of calculation that combines TRIGRS and the slope-units for estimating the landslide volume of a small mountainous watershed has been established. TRIGRS analyzes the watershed landslide safety factor under rainfall conditions based on grid-cells. The slope-units extract the results and combine the empirical power law formula to calculate the potential landslide volume. In this paper, we use this method to assess the landslide volume of the Longxi river basin. The results show that the area and volume estimates of the landslides are consistent with the results observed from satellite images and field surveys. This method can be used to study the impact of sediment transport on mountain torrent disasters in the basin. With different moisture content conditions, the results show that the soil moisture content and slope angle significantly affect the distribution and volume of potential landslides in the watershed, giving rise to the uncertainty of the landslide estimation.

Marxism, nationalism and modernization processes in Eastern Europe in the middle of 19th – early 20th century

The aim of the article is to elucidate the impact of Marxism and Nationalism on modernization processes in Eastern Europe from the perspective of their formation and mutual influence. Research methods: synthesis, induction, analysis, retrospective. Main results. During research we studied programs of both ideologies and compared their distinctive traits. Through analysis oftheoretical patterns of nationalism movements, different theories of public modernization and European point of view about backwardness, we found that Nationalism and Marxism significantly diverged around the role of statehood in culture and political changes. For Nationalism – state was the main aim and, simultaneously, result of nationalist movement activity. Further progress of nation was related to national state, which could provide certain conditions for cultural and economic development. Statehood in Marxists views was unwelcome; changes in society were related to social revolutionary movements without creation new state formations. State’s participation in transformation processes was, in theory, different for both ideologies. But when communists seized a power in the former Russian Empire, they faced a necessity of making their own statehood with its national policy. In fact, Nationalism became an artificial method on the way towards modernization of society. In conclusion, Eastern Europe modernization happened due to unification of communist and nationalist political thought. Scientific novelty of the paper is explained by analysis of works by Austrian Marxists, who made a theory for Soviet national policy. We explain this point by comparing some Austrian ideas to J. Stalin’s view on national question. The author also advocates the idea of existence some nationalistic traits during socialistic modernization in the USSR. Practical value of the research is a creation of background for studying Soviet ideology from new point of view. Type of article: empirical research.

An Empirical Evaluation of a Test Procedure for the Median of Symmetrical and Asymmetrical Populations Using an Interpolated Nonparametric Confidence Interval

This paper investigates, evaluates, and highlights the performance of a test procedure for the median of a single population using an old nonparametric interpolated confidence interval. Simulation results show that the test procedure under investigation strictly maintains the size at its nominal level and has generally higher empirical power under both symmetrical heavy-tailed and asymmetrical populations.

A group sequential design and sample size estimation for an immunotherapy trial with a delayed treatment effect.

A delayed treatment effect is often observed in the confirmatory trials for immunotherapies and is reflected by a delayed separation of the survival curves of the immunotherapy groups versus the control groups. This phenomenon makes the design based on the log-rank test not applicable because this design would violate the proportional hazard assumption and cause loss of power. Thus, we propose a group sequential design allowing early termination on the basis of efficacy based on a more powerful piecewise weighted log-rank test for an immunotherapy trial with a delayed treatment effect. We present an approach on the group sequential monitoring, in which the information time is defined based on the number of events occurring after the delay time. Furthermore, we developed a one-dimensional search algorithm to determine the required maximum sample size for the proposed design, which uses an analytical estimation obtained by the inflation factor as an initial value and an empirical power function calculated by a simulation-based procedure as an objective function. In the simulation, we tested the unstable accuracy of the analytical estimation, the consistent accuracy of the maximum sample size determined by the search algorithm and the advantages of the proposed design on saving sample size.

Sample size calculations for single-arm survival studies using transformations of the Kaplan-Meier estimator.

In single-arm clinical trials with survival outcomes, the Kaplan-Meier estimator and its confidence interval are widely used to assess survival probability and median survival time. Since the asymptotic normality of the Kaplan-Meier estimator is a common result, the sample size calculation methods have not been studied in depth. An existing sample size calculation method is founded on the asymptotic normality of the Kaplan-Meier estimator using the log transformation. However, the small sample properties of the log transformed estimator are quite poor in small sample sizes (which are typical situations in single-arm trials), and the existing method uses an inappropriate standard normal approximation to calculate sample sizes. These issues can seriously influence the accuracy of results. In this paper, we propose alternative methods to determine sample sizes based on a valid standard normal approximation with several transformations that may give an accurate normal approximation even with small sample sizes. In numerical evaluations via simulations, some of the proposed methods provided more accurate results, and the empirical power of the proposed method with the arcsine square-root transformation tended to be closer to a prescribed power than the other transformations. These results were supported when methods were applied to data from three clinical trials.

Nonlinear dynamics and stages of damage of Ti6Al4V and Ti45Nb titanium alloys in very high cycle fatigue

The paper presents an experimental methodology aimed at evaluating a very-high cycle resource for aviation titanium alloys Vt-6 (Ti6Al4V) and Ti45Nb for medical applications with different microstructures (large-crystal and submicrocrystalline ones). The submicrocrystalline (SMC) state was obtained by an intensive plastic deformation realized in two ways: the three-dimensional forging for Ti45Nb and radial-shear rolling for Ti6Al4V. The experimental program tests high-cycle and very-high-cycle loading (number of cycles 107-109) realized using the in situ determination method of the accumulation of the irreversible fatigue damage by analyzing nonlinear forms of feedback in a closed system ultrasonic fatigue setup. This makes it possible to establish the connection of the microscopic fatigue mechanisms with the model views and consider the stages of the damage development based on the nonlinear kinetics of the defect accumulation under cyclic loading in high- and gigacycle fatigue modes. We established various relations between changes in the amplitude of the second harmonic of vibrations of the free end of the samples with different internal structures, which are associated with the mechanisms of stress relaxation and damage accumulation. The grain size reduction in Ti45Nb alloy by the three-dimensional forging improved the fatigue properties by 1.3-1.5 times, whereas for VT-6 alloy, the radial-shear rolling method could not increase the fatigue properties in the very high cycle fatigue range, which may be caused by the presence of large residual internal stresses. Based on the scale parameters obtained earlier from the fracture surface morphology and the relations established in this work, the kinetic equations for the origin and growth of fatigue cracks in the gigacycle loading range will be constructed. This equation, based on the empirical power parameters related to the structure of the material, will allow us to determine the number of cycles for the origin of an internal crack and its growth to the surface.

The Four Highest Clans of the Eastern Jin Era

The article shows the history of the heyday and decline of the four highest clans of the Southern Chinese Eastern Jin dynasty (Wang, Xie, Yu and Huan clans), which alternately with varying degrees of success acted as the second most powerful clan in the entire Eastern Jin Empire when the central power ceased to be a self-sufficient force and badly needed the support of noble clans (strong houses). The purpose of the study is to identify the main factors of the political longevity of the highest clans of the period under review. The methodology of this study includes the method of prosopographic and historical-genetic analysis of the four highest clans of the Eastern Jin era, between which there was a continuous and merciless political struggle for the highest civil and military posts in the Eastern Jin Empire. The perspective of clan issues and inter-clan relations in Jin history lies in the possibility of a detailed reconstruction of the specific historical context of the most important events in the history of China in the 4th‒5th centuries AD and will contribute to the development of elitology of early medieval China. As a result of the analysis of the history of the development of the four clans, it was concluded that the Wang clan achieved the greatest success during the Eastern Jin period, which was able to move from the local level of politics to the level of the Eastern Jin Empire. The very factor of the clan structures of Chinese society had a significant double impact on the historical and political process of the period of the Jin Empire, as well as the era of the Southern and Northern dynasties in general. The duality lies in the fact that, on the one hand, the continuous strife between the regional branches of the Sima clan (the revolt of the eight princes) undermined the basis of the power of the all-Chinese empire of Western Jin from the inside, and on the other hand, the same clan structures in combination with rather strong compatriot ties (the alliance of the regional branch of the ruling Clan Sima and the local noble clan Wang) allowed the ruling house of Sima to retain supreme power and minimized the loss of the Chinese ethnos in a troubled and turbulent era. The system of the highest clans of the Jin era, in fact, developed as a result of the abandonment of the Han institute of examinations for officials, which prevented the highest clans from distributing among themselves the most important posts in the empire. Keywords: Western Jin, Eastern Jin, South China, higher clans, examination institute, nine-rank report card, prosopographic analysis

Educational Reforms and Sacralisation of Power in the First Empire (1804-1815). The Case of the Napoleonic Kingdom of Italy

Abstract: This work aims to highlight how, even in this particular territory closely linked to Paris and of which Napoleon was the sovereign, education became the object of significant reforms promoted by the political authorities. On one hand, these reforms intended to ensure a radical acceleration of the secularisation process of school education begun in Lombardy in the second half of the XVIIIth century, in turn fuel to the objectives that intended to add the basis of the principles of welfare also in this political domain. On the other hand, they aspired to root in the students adhesion to Bonaparte. As will be discussed later, this objective was pursued by encouraging students and teachers to engage themselves in writing encomiastic, flattering literary compositions, sometimes inspired by the most renowned literary works, which had to contribute to building the glorification of the monarch in the new political framework and which found a particular manifestation on the occasion of the birth of his male heir, the King of Rome, in 1811.

Discharge coefficient of broad-crested weirs as a function of the relative weir height for different weir lengths

Broad-crested weirs (BCW) are often used in hydraulic engineering and water management. The most complex factor that affects the discharge capacity of BCW is the discharge coefficient. In Ukrainian engineering practice, the flow rate of BCW is defined as a function of the relative height of the spillway wall, while in the most common European methods – as a function of the relative length of the weir. The experimental dependences of the discharge coefficient of rectangular sharp-edged BCW with vertical inlet and outlet walls with the ratio of the weir length and height d/Р = 2; 4 are obtained. A comparison of the obtained results with the values of the discharge coefficient of the same BCW using the methods of Kumin and Hager indicates that this coefficient depends on both the height of the wall and the length of the weir. The corresponding empirical power law dependences are obtained. At the same values of the relative height of the wall, the discharge coefficient for the weir with the ratio d/Р = 4 is significantly lower comparing the weir with d/Р = 2, that can be explained by the more significant effect of friction resistance for the weir with longer threshold.

Network Trees: A Method for Recursively Partitioning Covariance Structures.

In many areas of psychology, correlation-based network approaches (i.e., psychometric networks) have become a popular tool. In this paper, we propose an approach that recursively splits the sample based on covariates in order to detect significant differences in the structure of the covariance or correlation matrix. Psychometric networks or other correlation-based models (e.g., factor models) can be subsequently estimated from the resultant splits. We adapt model-based recursive partitioning and conditional inference tree approaches for finding covariate splits in a recursive manner. The empirical power of these approaches is studied in several simulation conditions. Examples are given using real-life data from personality and clinical research.

A tale of 3 scales: How do the 9-pt, Labeled Affective Magnitude, and unstructured Visual Analog scales differentiate real product sets of fresh berries?

Selection of scales for measuring liking remains an active area of discussion in sensory science, but there is still no real consensus on which scale a sensory scientist working in industry should use to measure actual hedonic responses to food products. Key criteria for a hedonic scale are whether it sensitively and efficiently discriminates among consumer responses to products. Therefore, the key question this study investigates is whether the use of different scales by the same subjects on the same products in a real-world situation would provide different results for the sensory analyst. To address this question, this study comprises the evaluation of 6 for-market varieties each of 4 berries—raspberry, strawberry, blackberry, and blueberry—by the same N = 147 untrained subjects using 3 popular scales—the 9-pt hedonic scale, the Labeled Affective Magnitude Scale (LAM), and the unstructured Visual Analog Scale (VAS). Data were analyzed by mixed-effects ANOVA with subsequent scale-performance and post-hoc measures, and by bootstrapping simulation studies to estimate the empirical power of each scale to detect differences. For each berry type, significant differences in liking were detected by at least one scale, but scale performance differed. The 9-pt scale was the only one of the three to detect differences among the blueberry samples, and examination of ANOVA and post-hoc results for all berries showed that the 9-pt scale consistently discriminated among samples as well or better than the other two scales. In simulation studies, the 9-pt scale showed reliable detection of differences at sample sizes smaller or equal to the other two scales. It is apparent that—in terms of real-world applications and expected detection of differences—the 9-pt scale discriminates consumer liking for different products as well or better than two continuous scales and can be retained in industry research programs.

Evaluation of Test Statistics for Detection of Outliers and Shifts

Existence of outliers and structural breaks having mutually unknown nature, in time series data, offer challenges to data analysts in model identification, estimation and validation. Detection of these outliers has been an important area of research in time series since long. To analyze the impact of these structural breaks and outliers on model identification, estimation and their inferential analysis, we use two data generating processes: MA(1) and ARMA(1,1). The performance of the test statistics for detecting additive outlier(AO), innovative outlier(IO), level shift(LS) and transient change(TC) is investigated using simulation strategy through power of a test, empirical level of significance, empirical critical values, misspecification frequencies and sampling distribution of estimators for the two models. The empirical critical values are found higher than the theoretical cut-off points, empirical power of the test statistics is not satisfactory for small sample size, large cut-off points and large model coefficient. We have explored confusion between LS, AO, TC and IO at different critical values(c) by varying sample size. We have also collected empirical evidence from time series data for Pakistan using 3-stage iterative procedure to detect multiple outliers and structural breaks. We find that neglecting shocks lead to wrong identification, biased estimation and excess kurtosis.
 JEL Classification Codes: C15, C18, C63, C32, C87, C51, C52, C82
 AMS Classification Codes: 62, 65, 91, DI, 62-08, 62J20, 00A72, 91-08, 91-10, 91-11 62P20, 91B82, 91B84, 62M07, 62M09, 62M10, 62M15, 62M20

Wetting Kinetics and Microstructure Analysis of BNi2 Filler Metal over Selective Laser Melted Ti-6Al-4V Substrate.

The wetting kinetics of nickel-based filler metal (BNi2) over selective laser-melted Ti-6Al-4V (SLMed TC4) titanium alloy in a protective argon atmosphere is experimentally investigated using a real-time in situ hot stage equipped with an optical microscope. The spreading processes at different temperatures are similar, and the overall wetting/spreading process can be roughly divided into three stages: (i) an initial stage, (ii) a rapid spreading stage, and (iii) an asymptotic stage. Moreover, the wetting kinetics of the BNi2/SLMed TC4 system can be expressed by empirical power exponential function Rn~t with n = ~1. In the process of spreading, Ti-based solid solution (Ti(ss)) and intermetallic compound (Ti2Ni and TiB2) were formed at the interface within the reaction domain, and the phase transition of α’ martensitic to α-Ti and β-Ti also took place. The influence of elevated temperature on the spreading and wetting kinetics of the BNi2/SLMed TC4 system was studied, and the results show that the increase of temperature has a slightly promoting effect on the spreading, but a limited impact on the value of n. In addition, the spreading and wetting kinetics of BNi2/SLMed TC4 system are similar to those of BNi2 on conventional forged TC4 substrate.