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As a crucial development direction for the sixth generation of mobile communication networks (6G), Low Earth Orbit (LEO) satellite networks exhibit characteristics such as low latency, seamless coverage, and high bandwidth. However, the frequent changes in the topology of LEO satellite networks complicate communication between satellites, and satellite power resources are limited. To fully utilize resources on satellites, it is essential to determine the association between satellites before power allocation. To effectively address the satellite association problem in LEO satellite networks, this paper proposes a satellite associationbased resource allocation algorithm. The algorithm comprehensively considers the throughput of the satellite network and the fairness associated with satellite correlation. It formulates an objective function with logarithmic utility by taking the logarithm and summing the satellite channel capacities. This aims to maximize the sum of logarithmic utility while promoting the selection of fewer associated satellites for forwarding satellites, thereby enhancing the fairness of satellite association. The problems of satellite association and power allocation are solved under constraints on resources and transmission rates, maximizing the logarithmic utility function. The paper employs an improved Kuhn-Munkres (KM) algorithm to solve the satellite association problem and determine the correlation between satellites. Based on the satellite association results, the paper uses the Lagrangian dual method to solve the power allocation problem. Simulation results demonstrate that the proposed algorithm enhances the fairness of satellite association, optimizes resource utilization, and effectively improves the throughput of LEO satellite networks. [ABSTRACT FROM AUTHOR]

This article explores the use of dynamic software to visualize and comprehend exponential and logarithmic identities in mathematics education. The authors emphasize the importance of approaching mathematical concepts from various perspectives, including numerical, graphical, symbolic, verbal, and dynamic, to accommodate different learning styles. They provide examples of dynamic spreadsheets that illustrate logarithmic and exponential identities, such as the logarithm of a power, product, quotient, and reciprocal. These visual representations aid students in comprehending and retaining these identities. The authors offer their spreadsheets for instructors and students to utilize in the classroom. The text also discusses several fundamental identities for exponential and logarithmic functions, including the sum, difference, product, and quotient identities for exponential functions, as well as the inverse function identities for exponential and logarithmic functions. The authors provide dynamic spreadsheets that allow users to explore these identities graphically and numerically. They recommend using Excel for these demonstrations due to its widespread availability and familiarity among students. The authors suggest incorporating a few of these modules in a classroom setting to enhance student understanding of the identities. [Extracted from the article]

This article aims to identify the general mathematical connections and those related to exponential and logarithmic functions, promoted by the Colombian intended mathematics curriculum. In this research, Content Analysis was used, and the official and institutional Colombian intended mathematics curriculum (of 5 schools) at the middle and high school level were used as a source of information. In Colombian, the official curriculum is made up of three official documents and to select the institutional curriculum, convenience sampling was used. Among the results, we find that, although the Colombian intended curriculum assumes the idea that making mathematical connections contributes to the development of understanding and promotes some of these (feature, meaning, different representations, and modeling), the reversibility connection is not identified -- which we consider central -- between exponential and logarithmic functions, which shows that the teaching of these is encouraged separately. This can influence what occurs in the classroom and, therefore, is one of the possible causes of the difficulties presented in students when solving tasks related to both functions. In this sense, it is necessary that institutions consider that making mathematical connections contributes to the understanding of students and therefore must be considered when designing the curriculum. It is necessary to promote the mathematical connection of reversibility between the functions that are addressed in this study and between the objects with which it is possible to make inverse relationships. [ABSTRACT FROM AUTHOR]

Due to improper acquisition settings and other noise artifacts, the image degraded to yield poor mean preservation in brightness. The simplest way to improve the preservation is the implementation of histogram equalization. Because of over-enhancement, it failed to preserve the mean brightness and produce the poor quality of the image. This paper proposes a multi-scale decomposition for brightness preservation using gamma correction. After transformation to hue, saturation and intensity (HSI) channel, the 2D-discrete wavelet transform decomposed the intensity component into low and high-pass coefficients. At the next phase, gamma correction is used by auto-tuning the scale value. The scale is the modified constant value used in the logarithmic function. Further, the scale value is optimized to obtain better visual quality in the image. The optimized value is the weighted distribution of standard deviation-mean of low pass coefficients. Finally, the experimental result is estimated in terms of quality assessment measures used as absolute mean brightness error, the measure of information detail, signal to noise ratio and patch-based contrast quality in the image. By comparison, the proposed method proved to be suitably remarkable in retaining the mean brightness and better visual quality of the image. [ABSTRACT FROM AUTHOR]

This research aims to study the influence of logarithmic and exponential functions on the multi-criteria decision-making algorithm that changes the linear to the nonlinear method. It is carried out to better understand the multi-criteria decision-making (TOPSIS) algorithm whereby these functions may influence the criteria weights during the selection of the best network. The experiment is applied under different network types to evaluate the most optimum network that leads to better throughput, low latency, minimum BER, and low price per MB. The algorithms are assessed in MATLAB simulation environments. In addition, the adoption of the Wi-Fi networks standard is determined by factors such as bandwidth, signal to noise ratio and the channel modulation technique during the decision-making process. The simulation results showed that the exponential function had produced approximately similar results to that of linear TOPSIS algorithm because both keep the weights to demonstrate positive values. However, logarithmic TOPSIS produced different results and a worstcase scenario, as the weights have negative values which lead to a phase shift of 180° during the decision process. Thus, linear TOPSIS was found to have the best results while logarithmic TOPSIS had the worst outcome. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Various control parameters of the dry-wet cycles can affect the development of expansive soil damage. It is important to study the fatigue damage characteristics of expansive soil under dry-wet cycles of constant amplitude. This paper considers expansive soil from Baise in Guangxi, China as the research object. Based on tests of the P-wave velocity and low-stress shear strength of expansive soil under 0-6 constant amplitude drywet cycles, the attenuation laws for the P-wave velocity were analyzed, the damage variable of expansive soil was characterized by P-wave velocity, and the rationality of this damage variable was verified by measuring the low-stress shear strength values of expansive soil specimens. Based on the experimental P-wave velocity results, a nonlinear empirical model of fatigue damage for expansive soil was constructed. As a result, the P-wave velocity of an expansive soil sample decreases nonlinearly with an increasing number of dry-wet cycles and that the damage degree increases nonlinearly with an increasing number of cycles. The cohesive force and damage degree of expansive soil show an attenuation relationship that is well fit by a logarithmic function; in general, the damage characteristics of expansive soil are closely related to the dry-wet cyclic loading path. [ABSTRACT FROM AUTHOR]

A novel low-rank completion algorithm based on the quaternion tensor is proposed in this paper. This approach uses the TQt-rank of quaternion tensor to maintain the structure of RGB channels throughout the entire process. In more detail, the pixels in each frame are encoded on three imaginary parts of a quaternion as an element in a quaternion matrix. Each quaternion matrix is then stacked into a quaternion tensor. A logarithmic function and truncated nuclear norm are employed to characterize the rank of the quaternion tensor in order to promote the low rankness of the tensor. Moreover, by introducing a newly defined quaternion tensor discrete cosine transform-based (QTDCT) regularization to the low-rank approximation framework, the optimized recovery results can be obtained in the local details of color videos. In particular, the sparsity of the quaternion tensor is reasonably characterized by l 1 norm in the QDCT domain. This strategy is optimized via the two-step alternating direction method of multipliers (ADMM) framework with convergence analysis. Numerical experimental results for recovering color videos show the obvious advantage of the proposed method over other potential competing approaches. • A novel quaternion tensor completion model is developed in this work. • The sparse regularization of the target quaternion tensor is designed. • This algorithm is optimized via the ADMM-based framework, and convergence analysis is presented. [ABSTRACT FROM AUTHOR]

This paper constructs a transcendental logarithmic cost function for describing the production technology of banks. Rather than adopting traditional approaches, this paper develops a new approach to specify the essential outputs and inputs of banks. It is finds that banks had to tolerate higher operating costs in the first few years after the removal of regulations. In response, banks sought for new revenue by expanding fee-based financial services rather than reduced operating costs by adjusting their input combinations or output combinations. The deregulation also forced banks to pursue active technical progress, and larger banks performed better than smaller banks. [ABSTRACT FROM AUTHOR]

The former consensus on a link between energy consumption and improved well-being of a country has been scrutinized by scholars for decades and is, succinctly, for the time being a contested thesis. Until the 1970s the relation of energy to well-being was defined as linearly proportional, and in a later period still as an increasing logarithmic function. Recent empirical research falsified the assumption of an overt link between well-being and increased energy consumption in countries with high per-capita energy usage. Going forward, our research shows for the first time a possible proof for a negative correlation between energy consumption and well-being after a Well-being Turning Point (WTP). We used a world data set, not limited to high-income countries but including 176 nations with available data sets. Our findings could support both the logarithmic growth of well-being together with energy, as well as the contradicting saturation theses supporting degrowth, and thus opens the discussion in all directions. In this paper Energy Footprint data within Eora database and Global Multi Regional Input Output methodology have been calculated, which includes also the energy embodied in imported/exported products and services (also known as consumption-based energy accounts). The use of footprint accounts has been demonstrated in our previous research to be necessary when analysing global energy consumption trends; as it records the energy consumption reality better than the usually used Total Primary Energy Supply which is provided by the International Energy Agency. In this paper, we provide in a novel way, some statistical support for an Energy WTP, i.e. a high-energy threshold after which a further consumption increase results in a reduced Human Development Index. We tested our results for possible biases (e.g. excluding outlier countries and including a factor for considering the weight of high population countries) and concluded that a WTP is one possible interpretation of the data. Thus, we would like to open a discussion about how energy consumption could end up having a negative effect on well-being, considering its indirect impacts in citizens of a country. Unlabelled Image • First evidences for a Well-being Turning Point (WTP), supporting a well-being degrowth beyond high-energy footprint threshold. • The WTP is a novel argument to support degrowth from energy perspective. • The WTP can be neither fully proven nor falsified with current data. • The WTP is not visible when the fitting was population-weighted. • The WTP is not visible if oil exporting countries and some small countries are excluded. [ABSTRACT FROM AUTHOR]

Term weight algorithms based on inverse document analysis are widely used in the expression of characteristic information for text. According to the finding that frequently occurring terms always cover less feature information for the text, the terms with lower frequency will be endowed higher weight. However, the terms with little occurrences always display unimportant information or even error information, such as rare terms and misspelled terms. To tackle such a problem, this paper proposed a novel term weight algorithm that focuses on the terms with low frequency rather than little occurrences. With the statistics based on non-homogeneous compression of term frequency, the action of terms with concerned frequency will be highlighted. And logarithmic function combined with the number of terms with the same frequency is utilized to weight the terms with different frequency based on different compression intervals. Comparing with TF-IDF and SIF, the proposed approach has a similar performance with SIF and a little better than TF-IDF. According to the difference among such methods, a finding shows that the term with a low frequency rather than little occurrences may dominate the feature information of the text. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this paper is to propose the novel generalized exponential intuitionistic fuzzy entropy (GIFE) and generalized exponential interval valued intuitionistic fuzzy entropy (GIVIFE) with interval area. First, we propose a novel GIFE. Then we compare the new GIFE with the existing intuitionistic fuzzy entropy (IFE) measures. Second, we define the interval area and the new axioms for the interval valued intuitionistic fuzzy entropy (IVIFE). Third, according to the newly defined axioms for the IVIFE, we use the interval area to construct the new GIVIFE. Finally, the advantages of the new generalized entropy measures are compared with the existing IVIFE measures by some examples. The two novel generalized exponential entropy measures can distinguish the special cases well. We have the conclusion that the two novel generalized entropy measures are reasonable and more flexible than the existing entropy. [ABSTRACT FROM AUTHOR]

Abstract Processing attribute reduction plays a key role in the fault diagnosis of incomplete decision information system (IDIS), and it improves the efficiency and accuracy of fault diagnosis. Tolerance relation-based attribute reduction is widely used in the IDIS. However, the fuzziness of relation-based classification always exists in the practical attribute reduction problems of fault diagnosis as the incompleteness and uncertainty of data information, and the traditional tolerance relation-based attribute reduction methods are not suitable for fault diagnosis of IDIS. Therefore, this paper proposes a hybrid hierarchical fault diagnosis method with the combination of tolerance relation-based attribute reduction method and integrated logarithmic fuzzy preference programming (LFPP) based methodology. The method utilizes both qualitative and quantitative data information and constructs the hierarchical structure of fault diagnosis in IDIS. The integrated LFPP based methodology obtains the unique normalized optimal significance priorities vector for attribute fuzzy pairwise comparison matrices simultaneously and directly as the sorting part of proposed method. The tolerance relation-based attribute reduction method decomposes the fault attributes reduction problem into multiple sub-problems, which is the decomposing part of proposed method. Hence, the proposed hybrid method can handle the fuzziness of relation-based classification and mitigate complexity attribute reduction for fault diagnosis of IDIS. Finally, an engineering case for strategy reduction of fault diagnosis is provided to demonstrate the feasibility of the proposed method and obtain the reduction diagnosis strategies. Another test case is given for verifying the validity of the reduction results and for comparison between the proposed method and other different methods, which shows that the method is indeed efficient and has greater advantages at producing higher accuracy, reducing difficulty and mitigating complexity in fault diagnosis. Graphical abstract Highlights • The hierarchical diagnosis method is for incomplete decision information system. • It utilizes qualitative and quantitative data information. • The method can always obtain a unique optimal significance priority vector. • It also can decompose the complex reduction problem into multiple sub-problems. • The method can mitigate complexity, reduce difficulty and acquire higher accuracy. [ABSTRACT FROM AUTHOR]

In this work, we have performed the flume study to analyze the high-order velocity moments of turbulent boundary layer with and without downward seepage. Sediment transport experiments were done in the laboratory for no seepage (NS), 10% seepage (10%S), and 15% seepage (15%S) cases. Measures of streamwise velocity variance were found increasing with seepage, which lead to increase in sediment transport with seepage. Results show that the variance of streamwise velocity fluctuation follows logarithmic law with distance away from the bed, within inner layer. This observation is also valid for even-order moments obtained in this work. The results show that the (2p-order moments)1/p also follows logarithmic law. The slopes Ap in the turbulent boundary layer seem fairly unaffected to NS and seepage flow but follows nonuniversal behavior for NS and seepage runs. The computed slope based on the Gaussian statistics does not agree well with the slope obtained from the experimental data and computed slope are reliable with sub-Gaussian performance for NS flow and super-Gaussian behavior for seepage flow. [ABSTRACT FROM AUTHOR]

China’s energy saving at the provincial level has important policy implications for the mitigation of the greenhouse gas emissions in the world. Therefore, this study uncovers the driving forces of the changes of the provincial energy consumption by distinguishing the domestic and interregional trade based on the MRIO-based SDA technique for the period of 1997–2011. We find that (1) final demand per capita was the top determinant of the increments in provincial energy consumption, while both energy intensity and production structure offset the provincial energy changes; (2) most of 30 provinces were outsourcers due to the close interprovincial linkages; (3) product flows from utility and raw materials of upstream resource-dependent provinces were supplied to the coastal provinces, which are the manufacturing hubs. This implies policy making for the reduction of provincial energy in China should simultaneously implement measures on production-side and consumption-side. This is even more important when considering the embodied energy due to the interprovincial linkages within China. [ABSTRACT FROM AUTHOR]

To explore the mechanisms concerning adfreezing strengths at the interface between frozen fine sand and structures, a series of experiments were conducted using a direct shear apparatus. The main results were as follows: All adfreezing strengths increased with decreasing temperature and increasing normal stress and surface roughness. Peak adfreezing strength (peak shear stress at failure) had a linear relationship with temperature, its relationship with normal stress was in line with the Mohr-Coulomb criterion, and its relationship with roughness satisfied a logarithmic function. Residual adfreezing strength (post-peak shear stress) varied with temperature and normal stress and presented three typical regular patterns-sustained stable, first stable and then fluctuating, and circularly fluctuating. The fluctuation cycle about strength curves increased with increasing roughness. An empirical formula on adfreezing strengths incorporating temperatures, normal stress, and roughness was constructed. [ABSTRACT FROM AUTHOR]

BACKGROUND Taylor's law (TL) states a linear relationship on logarithmic scales between the variance and the mean of a nonnegative quantity. TL has been observed in spatiotemporal contexts for the population density of hundreds of species including humans. TL also describes temporal variation in human mortality in developed countries, but no explanation has been proposed. OBJECTIVE To understand why and to what extent TL describes temporal variation in human mortality, we examine whether the mortality models of Gompertz, Makeham, and Siler are consistent with TL. We also examine how strongly TL differs between observed and modeled mortality, between women and men, and among countries. METHOD We analyze how well each mortality model explains TL fitted to observed occurrence- exposure death rates by comparing three features: the log-log linearity of the temporal variance as a function of the temporal mean, the age profile, and the slope of TL. We support some empirical findings from the Human Mortality Database with mathematical proofs. RESULTS TL describes modeled mortality better than observed mortality and describes Gompertz mortality best. The age profile of TL is closest between observed and Siler mortality. The slope of TL is closest between observed and Makeham mortality. The Gompertz model predicts TL with a slope of exactly 2 if the modal age at death increases linearly with time and the parameter that specifies the growth rate of mortality with age is constant in time. Observed mortality obeys TL with a slope generally less than 2. An explanation is that, when the parameters of the Gompertz model are estimated from observed mortality year by year, both the modal age at death and the growth rate of mortality with age change over time. CONCLUSIONS TL describes human mortality well in developed countries because their mortality schedules are approximated well by classical mortality models, which we have shown to obey TL. CONTRIBUTION We provide the first theoretical linkage between three classical demographic models of mortality and TL. [ABSTRACT FROM AUTHOR]

Copyright of Paradigma is the property of Universidad Pedagogica Experimental Libertador and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of mean flow velocity on phosphorus (P) partitioning between water and sediment has received much attention in recent decades. However, the impact of turbulence on the efficiency and capability of sediment adsorbing and desorbing dissolved inorganic phosphorus (DIP) is still unclear. A series of contrasting experiments on the sediment sorption and desorption of DIP with the flow turbulence kinetic energy (TKE) ranging from 1.95 to 2.93 pa have been conducted. It was found that the adsorbed P onto unit mass of sediment increases with the increase in TKE. It is because an increase in TKE results in a rise in the effective adsorption capacity of sediment (b m) by 20–30% during the adsorption process. The b m shows the maximum rise from 0.18 to 0.25 mg/g when TKE increases from 1.95 to 2.93 pa with a fixed sediment concentration of 0.5 g/L. To account for the direct effect of TKE on P adsorption, the Langmuir model is modified by introducing a newly defined coefficient (f A − TKE). The f A − TKE shows a good linear relationship with TKE. Comparison between the modified model and the classic model shows that the amount of adsorbed P could be overestimated by over 50% if the direct effect of turbulence intensity is ignored. The experimental data show that the increase in TKE also enhances the desorption process, with the degree of P desorption (D des) increased by 44%. The relation between D des and TKE can be well represented using a logarithmic function to quantify the direct effect of turbulence intensity on desorption of P. [Display omitted] • The direct effect of turbulence on sediment adsorption and desorption of P is investigated. • The mathematic relationship between the effective adsorption capacity of sediment and TKE is established. • A new Langmuir model (TKE- SCA-Langmuir model) considering the direct effect of turbulence on P adsorption is built. • The direct effect of turbulence should be considered in numerical model to get realistic value of adsorbed P. [ABSTRACT FROM AUTHOR]

Selecting optimum maintenance strategies plays a key role in saving cost, and improving the system reliability and availability. Analytic hierarchical process (AHP) is widely used for maintenance strategies selection in the Multiple Criteria Decision-Making (MCDM) field. But the traditional or hybrid AHP methods either produce multiple, even conflict priority results, or have complicated algorithm structures which are unstable to obtain the optimum solution. Therefore, this paper proposes an integrated Logarithmic Fuzzy Preference Programming (LFPP) based methodology in AHP to solve the optimum maintenance strategies selection problem. The multiplicative constraints and deviation variables are applied instead of additive ones to utilize both qualitative and quantitative data, and process the upper and lower triangular fuzzy judgments to obtain the same priorities. The proposed methodology can produce the unique normalized optimal priority vector for fuzzy pairwise comparison matrices, and it is capable of processing all comparison matrices to obtain the global priorities simultaneously and directly in the form of super-matrix according to the different requirements and judgments of decision-makers. Finally, an example is provided to demonstrate the feasibility and validity of the proposed methodology. [ABSTRACT FROM AUTHOR]

We measured 15 parent polycyclic aromatic hydrocarbons (PAHs) in atmosphere and water during a research cruise from the East China Sea (ECS) to the northwestern Pacific Ocean (NWP) in the spring of 2015 to investigate the occurrence, air–sea gas exchange, and gas–particle partitioning of PAHs with a particular focus on the influence of East Asian continental outflow. The gaseous PAH composition and identification of sources were consistent with PAHs from the upwind area, indicating that the gaseous PAHs (three-to five-ring PAHs) were influenced by upwind land pollution. In addition, air–sea exchange fluxes of gaseous PAHs were estimated to be −54.2–107.4 ng m −2 d −1 , and was indicative of variations of land-based PAH inputs. The logarithmic gas–particle partition coefficient (log K p ) of PAHs regressed linearly against the logarithmic subcooled liquid vapor pressure (log P L 0 ), with a slope of −0.25. This was significantly larger than the theoretical value (−1), implying disequilibrium between the gaseous and particulate PAHs over the NWP. The non-equilibrium of PAH gas–particle partitioning was shielded from the volatilization of three-ring gaseous PAHs from seawater and lower soot concentrations in particular when the oceanic air masses prevailed. Modeling PAH absorption into organic matter and adsorption onto soot carbon revealed that the status of PAH gas–particle partitioning deviated more from the modeling K p for oceanic air masses than those for continental air masses, which coincided with higher volatilization of three-ring PAHs and confirmed the influence of air–sea exchange. Meanwhile, significant linear regressions between log K p and log K oa (log K sa ) for PAHs were observed for continental air masses, suggesting the dominant effect of East Asian continental outflow on atmospheric PAHs over the NWP during the sampling campaign. [ABSTRACT FROM AUTHOR]

The main idea of this work is to study the effect of knitted fabric characteristics on capillary rise and sorption ability by combining experimental and mathematical approaches. An experimental device performing the vertical suspension of fabric-liquid surface and permitting the penetration of water molecules through the tested samples is used. Experimental values of vertical wicking were gravimetrically measured using an electronic microbalance, and theoretically studied using the linear logarithmic model (LLM). The results show that the theoretical predictions are in reasonable agreement with the experimental data with high correlation coefficients values. It is also demonstrated that capillary rise kinetics are influenced by knitted fabric features, such as composition, knit structure, type of yarn and ofcouliering depth value. Water sorption kinetics of cotton fabrics have also been studied and modeled by using mass measurements of the water absorbed by the textile and the LLM equation in order to interpret the experimental data in terms of sorption ability. [ABSTRACT FROM AUTHOR]

Digital watermarking has drawn extensive attention for copyright protection of multimedia data. This paper introduces a blind audio watermarking scheme in discrete cosine transform (DCT) domain based on singular value decomposition (SVD), exponential operation (EO), and logarithm operation (LO). In our proposed scheme, initially the original audio is segmented into non-overlapping frames and DCT is applied to each frame. Low frequency DCT coefficients are divided into sub-bands and power of each sub band is calculated. EO is performed on the sub-band with highest power of the DCT coefficients of each frame. SVD is applied to the exponential coefficients of each sub bands with highest power represented in matrix form. Watermark information is embedded into the largest singular value by using a quantization function. Simulation results indicate that the proposed watermarking scheme is highly robust against different attacks. In addition, it has high data payload and shows low error probability rates. Moreover, it provides good performance in terms of imperceptibility, robustness, and data payload compared with some recent state-of-the-art watermarking methods. [ABSTRACT FROM AUTHOR]

This paper proposes a model of switched quasilogarithmic quantizer for speech signal based on G.711 standard with usage of Golomb-Rice (GR) coding. In order to achieve better performances a method with switched quantizer is applied. Variance range is split into quantizers and for each of them a separate quantizer is designed, i.e. the support region is determined. Optimization of the support region and choice of the parameter μ is done in order to obtain a quantizer that obeys G.712 standard and gives minimal average bit rate. Every quantizer within the variance range has own model with a two-stage coder. Two stages are introduced with purpose to reduce the bit rate, whereby GR code plays its role as Variable Length Code (VLC). The first stage uses a GR coder for coding segments of the quantizer's support region, whereas the second stage applies the coding method with fixed code lengths for coding cells within a segment. GR has simpler and cheaper hardware realization than other VLC codes, Huffman's for instance, with very satisfying results regarding quality of quantized signal. [ABSTRACT FROM AUTHOR]

The derivation on the differential-valued field Tlog of logarithmic transseries induces on its value group ${{\rm{\Gamma }}_{{\rm{log}}}}$ a certain map ψ. The structure ${\rm{\Gamma }} = \left( {{{\rm{\Gamma }}_{{\rm{log}}}},\psi } \right)$ is a divisible asymptotic couple. In [7] we began a study of the first-order theory of $\left( {{{\rm{\Gamma }}_{{\rm{log}}}},\psi } \right)$ where, among other things, we proved that the theory $T_{{\rm{log}}} = Th\left( {{\rm{\Gamma }}_{{\rm{log}}} ,\psi } \right)$ has a universal axiomatization, is model complete and admits elimination of quantifiers (QE) in a natural first-order language. In that paper we posed the question whether Tlog has NIP (i.e., the Non-Independence Property). In this paper, we answer that question in the affirmative: Tlog does have NIP. Our method of proof relies on a complete survey of the 1-types of Tlog, which, in the presence of QE, is equivalent to a characterization of all simple extensions ${\rm{\Gamma }}\left\langle \alpha \right\rangle$ of ${\rm{\Gamma }}$. We also show that Tlog does not have the Steinitz exchange property and we weigh in on the relationship between models of Tlog and the so-called precontraction groups of [9]. [ABSTRACT FROM PUBLISHER]

Deriving the fuzzy priorities of criteria from pairwise comparison results is a challenging task in fuzzy multi-criterion decision-making problems. Most past work accomplishes this task by estimating the values of fuzzy priorities or fitting the membership functions of fuzzy priorities using alpha-cut operations (ACO). The former is error-prone, while the latter is time-consuming. To address these issues, this study proposes an efficient approximating ACO (exACO) method by incorporating two novel treatments. First, both logarithmic and exponential functions are used to approximate the membership functions of fuzzy priorities. Second, the enumeration process in ACO is monitored and terminated if the α cuts of fuzzy priorities converge. The proposed methodology has been applied to two cases in the literature. According to the experimental results, the exACO method reduced the average estimation error by 80% while increasing the computational efficiency by 98%. The contribution of this study is to accurately derive fuzzy priorities while maintaining high computational efficiency. • An efficient approximating alpha-cut operations approach is proposed. • The exponential function is used to approximate the membership function of a fuzzy priority. • The enumeration process of alpha-cut operations is monitored to detect the convergence of fuzzy priorities. • The efficient approximating alpha-cut operations approach enhances accuracy and efficiency by 32% and 99%, respectively. [ABSTRACT FROM AUTHOR]

Two-dimensional sand tank experiments were designed to investigate the retention process of the capillary zone during the migration of light non-aqueous phase liquid (LNAPL) pollutants. The fine sand and silt media experiments simulated the LNAPL migration process given a shallow point source leakage scenario. The results indicate that the LNAPL was retained in the capillary zone. A retention factor, based on the ratio of the change in the vertical migration velocity of the LNAPL front with time, was proposed to quantitatively characterize the retention effect. The retention factor and time satisfied the function of σ = A × exp (− k t). And the retention factor increased gradually with time, indicating the enhanced retention effect of capillary zone on the vertical migration of LNAPL. The concentration change rate was then used to investigate the LANPL redistribution process, which had a relationship with time of ν c = B × ln (t) + C. The capillary zone could be divided from top to bottom into a weak retention zone (B > 0, v c < 0), a strong retention zone (B < 0), and a barrier zone (B > 0, v c > 0). The retention effect of capillary zone on LNAPL migration gradually strengthened during the vertical migration of LNAPL. In addition, the coefficient B had a relationship with the environmental factors (i.e., EC, pH, and ORP) of B = a × sin (b × α × β × γ) c and the fitting coefficient R2 of the function was above 0.913 for both media, indicating a strong correlation between the LNAPL redistribution process and the key environmental factors. [Display omitted] • The capillary zone has a significant retention effect on LNAPL migration. • Retention factor is proposed to quantitatively characterize the retention effect. • Relationship between concentration change rate and time is a logarithmic function. • Environmental factors relate to the LNAPL migration and redistribution processes. [ABSTRACT FROM AUTHOR]

Saturation flow rate as one of the important characteristics of traffic flow plays a key role to determine the capacity and delay in signalized intersections. So far, various studies have been done to evaluate the saturation flow rate at nearside legs of intersections which is fit to geometrical dimensions, traffic flow characteristics and the behaviour of the drivers. However, despite the deference between the above specifications, no study has been conducted on the saturation flow rate at far-side legs and considering the difference between the saturation flow rate at nearside and far-side legs in case of reducing the number of lanes, lane width and other effective factors, it seems to be necessary to determine the saturation flow rate at far-side legs. In the present study, using field data collection at five signalized intersections in Rasht city, the saturation flow rate is estimated and analyzed by macroscopic and microscopic methods, considering the existing lane width at nearside and far-side legs of the intersections. The results indicate that the values of saturation flow rate at far-side legs using the microscopic method are higher than the similar values in nearside legs. Also there is a primarily linear relationship (R 2 =0.957) between the lane width and saturation flow rate at far-side legs using the macroscopic method. There is an exponential non-linear relationship at far-side legs (R 2 =0.859) and a logarithmic non-linear relationship at nearside legs (R 2 =0.105) between the lane width and saturation flow rate using the microscopic method. In regard to far-side leg's R 2 , it seems that the main criterion in determining the saturation flow rate is the lane width, while at nearside leg more effective parameters need to be used to determine the values of saturation flow rate. [ABSTRACT FROM AUTHOR]

Effects of sex and handedness on the perception of temporal durations from 1 to 20 s were studied. A total of 80 male and 40 female participants were divided equally into left-handed and right-handed subgroups. Using an empty interval production procedure, each person estimated durations of 1, 3, 7, and 20 s, respectively, 50 times each. The order of presentation was randomized across participants but yoked across the sexes in each of the respective handedness subgroups. Results showed significant sex differences but no effects for handedness. One important facet of this sex effect was expressed in a consistent intercept difference in the identified relationship that linked the log-linear size of the absolute error of estimation against the logarithmic magnitude of the target duration at which such error was recorded. This new finding provides a new descriptive, empirical relationship for time perception of brief temporal intervals. The potential methodological, evolutionary, and cognitive reasons for this lawful relationship are discussed. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate of the effect of temperature variation on the logarithmic surface. By using the appropriate similarity transformation for the generation components and temperature, the basic equations governing flow and heat transfer are reduced to a set of ordinary differential equations. These equations have been solved approximately subject to the relevant boundary conditions with numerical and analytical techniques. The reliability and performance of the present method have been compared with the numerical method (Runge–Kutta fourth-rate) to solve this problem. Then, LSM is used to solve nonlinear equation in heat transfer. This method is useful and practical for solving the nonlinear equation in heat transfer. It is observed that the obtained results by present analytical method are very close to result of the numerical method. Furthermore, the results show that the temperature profiles decreased by increasing the α number, and, temperature profiles increased by increasing the β number. [ABSTRACT FROM AUTHOR]

In this paper, a Synthetic Aperture Radar (SAR) image despeckling technique, based on lapped orthogonal transform (LOT) domain dual local Wiener filtering framework, is proposed. A logarithmic transformation is employed to convert the speckle contribution into additive noise. It is demonstrated that the local distribution of dyadic rearranged LOT coefficients of logarithmically transformed SAR images are well approximated using Gaussian distribution. The proposed LT domain structure employs two local Wiener filtering procedures to despeckle the SAR images. The signal variance is estimated using elliptic directional windows for different oriented subbands. The motivation of using lapped transform (LT) is that they are robust to oversmoothing and preserve better oscillatory image components like textures. Experiments on real SAR images, show that the proposed method reduces speckle noise effectively while preserving textures and outperforms well known iterative probabilistic patch-based (PPB) filter and a recent directionlet based method, with much less computational complexity. [ABSTRACT FROM AUTHOR]

Research infrastructure is crucial for development of research, and thus the evaluation of its performance is important. However, existing researches mostly focus on its past observations, lacking of a prediction for future. In this paper, procedures are proposed to predict the distribution for the number of papers published in a certain future year. The publication reliability, which is defined as the probability that the number of published papers in the future year is bigger than a pre-specified number, is evaluated. Illustrative examples are proposed to show the applications of the model. [ABSTRACT FROM AUTHOR]

In our proposed model a hybrid method of tone mapping is presented. In this technique, an image of High Dynamic Range (HDR) is employed as input and split up into two layers i.e. base and detail layer. The details of HDR image will be preserved because only the base layer's contrast is brought down. A bilateral filter is used to obtain the base layer. Along the base layer the logarithmic compression is used and a bias power function is employed so that the logarithmic base can be varied adaptively and the contrast remains preserved. This tone mapping technique produces a high quality tone mapped image as specified in given experimental results. [ABSTRACT FROM AUTHOR]

The focus of this study was on developing a Saturation-Height Model (SHM) based on mercury injection capillary pressure (MICP) analysis and core data of three wells drilled in a deep tight gas reservoir of the Amin formation, Oman, that can best fit to the water saturation calculated by logging data. The suggested SHM is a porosity dependent natural logarithmic function. The SHM indicated homogeneous transition zone with a deep fluid contact similar to all three wells. The calibration with logging data allowed for obtaining the GWC and more precise coefficients in the SHM equation for specific wells. The SHM closely simulated log-derived water saturation for entire Amin formation unaffected by rock type, which makes it useful for complex lithologies and un-cored intervals. The developed SHM can be used as a tool for water saturation evaluation independent from electrical rock properties obtained by logging. [ABSTRACT FROM AUTHOR]

We have developed a novel method for Q estimation. As a seismic wave propagates through subsurface viscoelastic media, seismic attenuation decreases the amplitude and reduces the bandwidth, which leads to variation of the logarithmic spectral area of seismic wave. According to this property, we have derived an analytical relation between Q factor and the logarithmic spectral area difference of seismic wave. To improve the accuracy of Q estimation, we took account of the amplitude loss due to energy partitioning from transmission. Tests of the method on synthetic models determined the validity of our method, and it was insensitive to different types of noises and evaluated density. A further comparison between the presented method and two widely used Q estimation methods, namely, the logarithmic spectral ratio and centroid frequency shifting methods, with a synthetic model containing random noise demonstrated that our method is the more robust, in these situations, among the three approaches. Then, we also compared the effect of bandwidth and time-window selection on the Q estimation for these three methods, and the result revealed that our method is less sensitive to the bandwidth and time window than the other two methods. Application of this method to real zero-offset vertical seismic profile data shows a reasonable correlation between estimated interval-Q and interval velocities, which further indicates the validity of the method. [ABSTRACT FROM AUTHOR]

The Fast Fourier Transform is a very efficient algorithm for the Fourier spectrum estimation, but has the limitation of a linear frequency scale spectrum, which may not be suitable for every system. For example, audio and speech analysis needs a logarithmic frequency scale due to the characteristic of a human's ear. The Fast Fourier Transform algorithms are not able to efficiently give the desired results and modified techniques have to be used in this case. In the following text a simple technique using the Goertzel algorithm allowing the evaluation of the power spectra on an arbitrary frequency scale will be introduced. Due to its simplicity the algorithm suffers from imperfections which will be discussed and partially solved in this paper. The implementation into real systems and the impact of quantization errors appeared to be critical and have to be dealt with in special cases. The simple method dealing with the quantization error will also be introduced. Finally, the proposed method will be compared to other methods based on its computational demands and its potential speed. [ABSTRACT FROM AUTHOR]

Important progress occurred in pulse-stimulated thermography, in particular thanks to the TSR technique, a technique based on the decomposition of thermograms on a logarithmic polynomial basis and the use of the logarithmic derivatives to enhance the detection of defects in structures. Its fields of application begin to broaden to the characterization of transient internal heat sources in experimental mechanics and biomedicine. The TSR technique is presented, in particular the last developments leading to the production of a unique synthetic image. Two recent examples of applications in experimental mechanics and biomedicine, taken from literature, are described: in situ detection of damages in a composite material during mechanical tests and in vivo visualization of subcutaneous functional angioarchitecture in humans. [ABSTRACT FROM AUTHOR]

Under mild conditions, we find the best linear prediction of linear processes with arbitrary innovations. The prediction method is based on the theory of Hilbert spaces. Using the presented method we can predict non-causal ARMA processes. Finally, we utilize the presented method for prediction of natural logarithms of volumes of Wal-Mart stock traded daily. [ABSTRACT FROM AUTHOR]

Citing national publications is considered as a qualitative measure for science localization in the current research. Consequently, the aim is to study this metric within the corpus of Iranian Scholar Journals in Social Science Domain between 2002 and 2010. The research uses citation analysis method. The references of six social science scholar journals were extracted from the papers and then divided into two groups of national and foreign publications. The studied journals were those which were regularly published in Iran between 2002 and 2010. The analysis was performed on a sample of 543 papers out of 1528 ones. The sampling method was based on the Cochran's function. An ANOVA test showed that the average number of citing to national publications is statistically unchanged in the journals' papers during the period mentioned above. On the other hand, the same average for foreign publications is growing. The correlation analysis determined that this growth follows a logarithmic function. The other finding concerns the differences between the average numbers of citing to the national publications in the studied journals. A one way ANOVA test revealed a difference between the journals from this point of view. Based on the Tukey's Range Test the results of ANOVA test is affected by the "Journal of Women Strategic Studies". It means, if this journal was omitted from the analysis, the rest five ones would statistically have the same rate of citing to the national publications. The citing rate to national publications ranges between 0.31 and 0.39 except for the journal mentioned above. Based on this metric, the tendency toward the use of national publications in the social science domain is constant despite the growing number of scientific productions in Iran. This means that the Iranian social science domain not only doesn't tend to localization of science, but its use of foreign science is growing in the span of time as well. [ABSTRACT FROM AUTHOR]

Analogues of the key results of Wiman-Valiron theory are proved for a class of functions meromorphic in the unit disc, based on an approach developed by Bergweiler, Rippon and Stallard for the plane setting. The results give local approximations for the function and its logarithmic derivative and, in the case of positive order of growth, for higher order logarithmic derivatives as well. [ABSTRACT FROM AUTHOR]

This paper proposes a new method to derive the priority vector from fuzzy pairwise comparison matrices. Unlike several known methods, the proposed method derives crisp weights from consistent and inconsistent fuzzy comparison matrices. Therefore, the crisp weights obviate the need of additional aggregation and ranking procedures. To derive the priority vector, a Modified Fuzzy Logarithmic Least Square Model (MFLLSM) is proposed. In order to solve the MFLLSM, a framework based on genetic algorithm is proposed. In the proposed framework, a heuristic algorithm of population initialization, a heuristic algorithm for simulating fuzzy numbers and a heuristic algorithm of fitness evaluation are proposed. The solution of the prioritization problem requires finding priorities such that their ratio approximately satisfies the initial judgments. Computational results reveal the superiority of the proposed method in comparison with five well known methods of literature from the viewpoint of satisfaction of initial judgments by the obtained priority vector. It is shown by ten different examples that the deviation of the priorities ratio from initial judgments in the proposed method is less than five existing methods of literature. In addition, unlike several methods of literature, the proposed method considers fuzzy judgments represented by both triangular and trapezoidal fuzzy numbers. Furthermore, the proposed method for the first time considers judgments represented by triangular shaped fuzzy numbers and trapezoidal shaped fuzzy numbers which are discussed in the paper. [ABSTRACT FROM AUTHOR]

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This paper presents a new algorithm called the adaptive logarithmic increase and adaptive decrease algorithm (A-LIAD), which mainly addresses the Round-Trip Time (RTT) fairness problem in satellite networks with a very high propagation delay as an alternative to the current TCP congestion control algorithm. We defined a new increasing function in the fashion of a logarithm depending on the increasing factor α, which is different from the other logarithmic increase algorithm adopting a fixed value of α = 2 leading to a binary increase. In A-LIAD, the α value is derived in the RTT function through the analysis. With the modification of the increasing function applied for the congestion avoidance phase, a hybrid scheme is also presented for the slow start phase. From this hybrid scheme, we can avoid an overshooting problem during a slow start phase even without a SACK option. To verify the feasibility of the algorithm for deployment in a high-speed and long-distance network, several aspects are evaluated through an NS-2 simulation. We performed simulations for intra- and inter-fairness as well as utilization in different conditions of varying RTT, bandwidth, and PER. From these simulations, we showed that although A-LIAD is not the best in all aspects, it provides a competitive performance in almost all aspects, especially in the start-up and packet loss impact, and thus can be an alternative TCP congestion control algorithm for high BDP networks including a satellite network. [ABSTRACT FROM AUTHOR]

Most HR filter design algorithms aim to fit a complex target response, that is, both magnitude and phase. When this is not possible due to low filter order usually a magnitude-only filter design is applied. The magnitude-priority method presented in this paper combines the two approaches in such a way that the filter follows both magnitude and phase in those frequency regions where it can, while where this is not possible, it focuses on the magnitude. This is especially advantageous in audio applications where magnitude accuracy has higher priority. Moreover, it is shown that the new method compensates the high-frequency attenuation of logarithmic frequency resolution filter design methods often used in audio. The method can be implemented either by the iterative update of the magnitude, or by the iterative update of the phase of the target specification, giving similar performance. These two variants are demonstrated by the use of a parallel filter design, by a warped HR example, and finally by a windowed FIR design. [ABSTRACT FROM AUTHOR]