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Considering that industrial wastes such as granulated blast furnace slag (GBFS) and fly ash (FA) will be released less or more in the future, developing geopolymer composites with natural pozzolans is a critical issue today. In this study, geopolymer composites with different SS (sodium silicate)/SH (sodium hydroxide) rates (2.0, 2.5 and 3.0) were produced by NZ reinforcement at 5%, 10% and 15%, and their physicomechanical, transport, high-temperature resistance, microstructure, carbon footprint and cost features were investigated. Geopolymer composites had been heat-cured for 8 h at 80 °C. The porosity of geopolymer composites varies between 5.2 and 7.2%, while their water absorption is between 3.4 and 6.9%. The dry unit weight of all geopolymer composites is less than 2300 kg/m3. The compressive strength of the geopolymer composite with an SS/SH rate of 3 and an NZ rate of 5% was about 75 MPa, and the compressive strength of the geopolymer composite with an SS/SH rate of 2 and an NZ rate of 15% was about 40 MPa. The capillary water absorption value of geopolymer composites is generally less than 1 kg/m2. While the compressive strength of geopolymer composites exposed to 600 °C ranged from 21.2 to 40.5 MPa, using 5% and 10% NZ generally improved the high-temperature resistance. The carbon emission of geopolymer composites was between 391.4 and 400.8 kgCO2/kg, while the cost increased only slightly with increasing NZ content. As a result, NZ content of 10% when the SS/SH rate is 2.5 and NZ content of 5% when the SS/SH rate is 3 improves many features of geopolymer composites. [ABSTRACT FROM AUTHOR]

Verification (taḥqīq) was a post-classical practice in Islamicate scholarship that sought ways to attain syntheses between rational and religious sciences. This article argues, however, that the early Ottoman practice of taḥqīq was not limited to the "verification of theology and philosophy," as it also included attempts to reconcile certain Sufi doctrines with philosophical theology. This tendency is evident in the works of fifteenth-century scholars, such as Sinān Paşa and his shaykh Vefā', as well as al-Jāmī and İbn Kemāl, all of whom tried to reconcile conflicting aspects of philosophy and theology under the overarching rubric of the Akbarī worldview. These cases demonstrate that Sufi taḥqīq was already present very early in the development of Ottoman intellectual life, and that it was a diffuse and multi-variegated practice that drew upon the universalizing tendencies of Sufi agnosticism. [ABSTRACT FROM AUTHOR]

The Islamic world has mostly remembered Persian polymath ‘Omar Khayyām of Nīshāpūr (d. 526/1132 [?]) as a “Graeco-Arabic philosopher” (faylasūf) who also produced works in mathematics, theoretical astronomy, and astrology—not particularly in poetry. Yet Khayyām’s achievement of worldwide recognition as a poet goes back to nineteenth century London, where Edward FitzGerald’s translations of his poetry into modern English led him to be hailed as one of the greatest poets of all time. After briefly discussing the contributions Khayyām has made in the fields of philosophy and mathematics through new studies that have been made available, this article will analyze quatrains that Khayyām infused with Graeco-Arabic philosophical vocabulary. With an attempt to emphasize the Avicennan aspects of Khayyām’s worldview, this article will examine the earliest quatrains attributed to the poet with the aim of discovering new ways of commenting on his poetry. Certain philosophical terms with their bases in ontology, cosmology/cosmogony, epistemology, and physics, such as jawhar (substance), wujūd (existence), falak (the heavens), ma‘lūm (the object of knowledge), qadīm (the pre-eternity of the world), as well as the post-classical method of scholarly arbitration, taḥqīq (verification), are common features of the quatrains attributed to Khayyām. Disregarding the Sufi rogue (rind) image, as well as the mystical connotations displayed in Khayyām’s verses, this article focuses on the Graeco-Arabic philosophical references presented in these quatrains by contextualizing these references through doctrines in relevance at the time when Khayyām was writing۔ [ABSTRACT FROM AUTHOR]

The shecr-e now (new poetry) movement, having started with Nīmā's celebrated poem "Afsānah," went against the strict use of meter and rhyme in classical Persian poetry. In later stages of shecr-e now, the shecr-e safīd (white poetry) poets, of which Ahmad-e Shāmlū was the leading figure, moved towards a new type of free verse-like poetry, totally disregarding the importance of poetic harmony overall. When we look at shecr-e now's initial years of activity, we see that this movement is contemporaneous with Garip in Turkey; and similarly, shecr-e safīd was also active during the same years that the İkinci Yeni (second new) poets produced their first books. Yet being contemporaneous with Garip, the innovation that shecr-e now brought to poetry in Persian could be an equal of Tevfīk Fikret's "serbest müstezāt" convention (a type of free verse popularized during the Tanzīmāt era). In a similar fashion, that of shecr-e safīd would be an equal of the innovation that Garip brought to twentieth-century poetry in Turkish by breaking all the classical rules of previous conventions. One of the main reasons for this is that even though Nīmā and Shāmlū broke away with meter and rhyme, they were not able to break away completely from what Garip poets directed their criticism at: the notions of şairānelik (poeticality), eda (concord or manner), and istiare (metaphor) in poetry. Shāmlū went against āhang, a Persian word denoting poetic harmony, but āhang was never negated completely. Though both shecr-e now and shecr-e safīd tried to use spoken Persian a lot in their poetry, they were never able to abandon the harmony of written Persian completely in comparison to their contemporaries writing in Turkish. These two contemporaneous developments seem to be independent from one another, but we can still say that certain sociopolitical changes during the nineteenth century as well as the European influence were important factors in the development of twentieth-century poetry in Persian and Turkish. I will further assess the historical developments of twentieth-century poetry in Persian with a specific focus on the works of Faraydūn-e Moshīrī, who found the middle ground between shecr-e now and shecr-e safīd in terms of both form and aesthetics. [ABSTRACT FROM AUTHOR]

Abstract: Detecting and tracking ground targets is crucial in military intelligence in battlefield surveillance. Once targets have been detected, the system used can proceed to track them where tracking can be done using Ground Moving Target Indicator (GMTI) type indicators that can observe objects moving in the area of interest. However, when targets move close to each other in formation as a convoy, then the problem of assigning measurements to targets has to be addressed first, as it is an important step in target tracking. With the increasing computational power, it became possible to use more complex association logic in tracking algorithms. Although its optimal solution can be proved to be an NP hard problem, the multidimensional assignment enjoyed a renewed interest mostly due to Lagrangian relaxation approaches to its solution. Recently, it has been reported that randomized heuristic approaches surpassed the performance of Lagrangian relaxation algorithm especially in dense problems. In this paper, impelled from the success of randomized heuristic methods, we investigate a different stochastic approach, namely, the biologically inspired ant colony optimization to solve the NP hard multidimensional assignment problem for tracking multiple ground targets. [Copyright &y& Elsevier]

Interdischarge interval (IDI) is one of the basic parameters to study in motor unit firing analysis. Discharge intervals of a single motor unit vary over time and they are unpredictable. IDI sequences can be considered to comprise two components, namely a long term signal, an IDI trend, and a white noise process, instantaneous firing variability (IFV). In this paper a stochastic model of the IDI signal has been developed in order to estimate the elements of an IDI sequence. IDI sequences of several patients have been recorded at a clinic and a Kalman filter has been constructed based on the developed stochastic model. The Kalman filter is utilized to decompose the recorded IDI sequences into the IDI trend and IFV components. The obtained decomposed signals, especially the IDI trend component, may provide valuable information on motor unit firing performance and help diagnose neurological diseases. [ABSTRACT FROM AUTHOR]

The basic problem of simulation and modeling of Image Intensified Charge Coupled Device (ICCD) is the difference between the analytical Modulation Transfer Function (MTF) formulation used in the model and the experimentally obtained MTF. An investigation into the MTF of ICCD sub-components reveal that the MTF of the Image Intensifier Tube (IIT) is the main factor in this deviation. In this study, a regulation factor for the MTF of 3rd generation IITs has been developed. A commonly used MTF formulation for IITs has been modified to include a regulation factor which has helped produce more precise MTF values for the Night Vision Sight (NVS) device. The results obtained through the new formulation have been compared with the experimental results and it is revealed that the proposed formulation yields MTF values within 3% of the experimental results, on average, while the most commonly used formulation produces approximately 29.5% difference, which amounts to almost 10% improvement in analytical analysis. The analysis is then extended to other generations of IITs where similar improvements have been achieved. [ABSTRACT FROM AUTHOR]

In this paper the ingestion and subsequent metabolism of a drug in a given individual, are investigated through the use of compartmental models. An adaptive formulation of the widely used extended Kalman filter (EKF) has been derived in order to solve the resulting nonlinear estimation problem at the output of the compartments. The adaptive EKF employs a forgetting factor to emphasize artificially the effect of current data by exponentially weighting the observations. The dependence of EKF's performance on the selection of appropriate values of the arbitrary matrices, the measurement covariance R and the process noise covariance Q has been demonstrated through simulations. With the appropriate choice of the matrices the EKF provides a very useful tool for online estimation of both the state and the parameters. [ABSTRACT FROM AUTHOR]

The pair correlation function is introduced to target tracking filters that use a finite point process target model as a means to investigate interactions in the Bayes posterior target process. It is shown that the Bayes posterior target point process of the probability hypothesis density (PHD) filter?before using the Poisson point process approximation to close the recursion?is a spatially correlated process with weakly repulsive pair interactions. The reduced Palm target point process is introduced to define the conditional target point process given the state of one or more known targets. Using the intensity function of the reduced Palm process, an approximate two-stage pseudomaximum a posteriori track extractor is developed. The proposed track extractor is formulated for the PHD filter and implemented in a numerical study that involves tracking two nearby targets. Numerical results demonstrate improvement in the mean optimal subpattern assignment statistic for the proposed track extractor in comparison to the Gaussian mixture PHD filter?s state extractor. [ABSTRACT FROM AUTHOR]

In this paper, stability of the projection-based constrained discrete-time extended Kalman filter (EKF) as applied to nonlinear systems in a stochastic framework has been studied. It has been shown that like the unconstrained EKF, the estimation error of the EKF with known constraints on the states remains bounded when the initial error and noise terms are small, and the solution of the Riccati difference equation remains positive definite and bounded. Stability results are verified and performance of the constrained EKF is demonstrated through simulations on a nonlinear engineering example. [ABSTRACT FROM AUTHOR]

Extended target tracking (ETT) is an issue in high-resolution radar surveillance, ship tracking, and video tracking. Most of the previous works focus on tracking an ellipsoidal extended target without measurement origin uncertainty (missed detections and clutter). In this paper, a new estimator called the Gaussian process probabilistic data association (GP-PDA) filter is proposed to track an irregularly shaped extended target with measurement origin uncertainty. First, a generalized measurement model for ETT using the Gaussian process (GP) is presented. Both the interior scattering points and the external clutter are considered in this model. Second, a GP-based gating technique is constructed to select validated measurements to feed the filter. Third, the GP-PDA filter is proposed to simultaneously estimate the kinematic state and the contour state of the extended target with measurement origin uncertainty. It is proven that the GP-PDA is a generalized version of the classic PDA, and the latter is a special case of the former in the point target tracking applications. Finally, the GP-based posterior Cramér–Rao lower bound (PCRLB) is derived to evaluate the performance of the ETT with measurement origin uncertainty. Two cases of the PCRLB are discussed, with the number of scattering points being known and unknown. Simulation results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

We aimed to compare the efficacy of intra-articular injections of a lower molecular weight hyaluronan (LMW HA) (Ostenil) with a higher molecular weight viscosupplement (hylan G-F 20, Synvisc) in hip osteoarthritis. For this purpose, 43 patients (56 hips) with hip osteoarthritis with a visual analogue scale (VAS) pain score higher than 50/100, a Lequesne index greater than 6, and persistence of the pain for longer than 3 months despite all conservative methods were enrolled in the study and randomly assigned to two groups: 25 (32 hips) received LMW HA and the remaining 18 patients (24 hips) received hylan G-F 20. Three injections were administered once weekly to each patient under fluoroscopic guidance. During the 6-month follow-up period, the primary outcomes were assessed at the 1st, 3rd, and 6th month by VAS, WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), and Lequesne index. The intra-articular injections produced a significant reduction in VAS, WOMAC, and Lequesne index scores in both groups. After three injections, improvement was prominent at the 1st month and maintained for 6 months in both groups. The percentage reduction was 38 and 40% ( p<0.001) in VAS pain score, 43 and 40% in WOMAC ( p<0.001), and 47 and 49% in Lequesne index ( p<0.001) in the LMW HA and hylan G-F groups at the 6th month, respectively. However, there were no significant differences in outcomes between any of the measurements at the 1st, 3rd, and 6th month between the two groups ( p>0.05). No systemic adverse effect was recorded. Local adverse effects consisting of pain and/or swelling were noted in 3 of 32 hips (9%) injected with LMW HA and in 3 of 24 hips (12.5%) injected with hylan G-F 20. In conclusion, both types of viscosupplementation produced a significant clinical improvement during the 6-month follow-up period. However, no significant difference was found in outcomes between higher and lower molecular weight hyaluronan. [ABSTRACT FROM AUTHOR]

Conventional methods such as matched filtering, fractional lower order statistics cross ambiguity function, and recent methods such as compressed sensing and track-before-detect are used for target detection by passive radars. Target detection using these algorithms usually assumes that the background noise is Gaussian. However, non-Gaussian impulsive noise is inherent in real world radar problems. In this paper, a new optimization based algorithm that uses weighted l 1 and l 2 norms is proposed as an alternative to the existing algorithms whose performance degrades in the presence of impulsive noise. To determine the weights of these norms, the parameter that quantifies the impulsiveness level of the noise is estimated. In the proposed algorithm, the aim is to increase the target detection performance of a universal mobile telecommunication system (UMTS) based passive radars by facilitating higher resolution with better suppression of the sidelobes in both range and Doppler. The results obtained from both simulated data with α stable distribution, and real data recorded by a UMTS based passive radar platform are presented to demonstrate the superiority of the proposed algorithm. The results show that the proposed algorithm provides more robust and accurate detection performance for noise models with different impulsiveness levels compared to the conventional methods. [ABSTRACT FROM AUTHOR]

• Handling single 2-D radar 3-D tracking with false alarms and missed detections. • Solving the compatibility issue between initial altitudes and standard deviations. • A novel cascaded filter using the waypoint information. • Exploring the limits of tracking performance with a single 2-D radar and waypoints. • The derivation of posterior Cramr–Rao lower bound expressions. Three-dimensional (3-D) aircraft tracking using two-dimensional (2-D) radar measurements is a common task in air traffic control (ATC) systems. In this paper, a new algorithm using a 2-D ATC radar, called HPEKF with probabilistic data association (HP-PDA-EKF), is proposed for aircraft tracking with false alarms and missed detections. An improved filter initialization technique is also proposed to yield better estimates. To mitigate the degradation in altitude estimation accuracy with increasing aircraft distance, ATC waypoints are used as extra measurement information, and a new height-parametrized cascaded PDA filter (HP-CPDAF) algorithm is proposed to make use of waypoints. The posterior Cramér–Rao lower bounds (PCRLBs) quantifying the achievable accuracies of these two filters are derived. Simulations are carried out to analyze the relationship between aircraft distance, waypoint accuracy and state estimation accuracy. The viability of using a single 2-D radar for 3-D ATC and the usefulness of the proposed algorithms under different operating conditions are analyzed. Simulation results demonstrate the validity of the proposed algorithms. [ABSTRACT FROM AUTHOR]