Miracle-dz/UniFAR-FTUs huggingface dataset:
Numerical Investigation of Heat Transfer in the Wake of a Single Highly Confined Bubble in a Horizontal Minichannel

Confined bubbly flows in millimeter-scale channels produce significant heat transfer enhancement when compared to single-phase flows. Experimental studies support the hypothesis that the enhancement is driven by a convective phenomenon in the liquid phase as opposed to sourcing from microlayer evaporation or active nucleation. A numerical investigation of flow structure and heat transfer produced by a single bubble moving through a millimeter-scale channel was performed in order to document the details of this convective mechanism. The simulation includes thermal boundary conditions emulating those of the experiments, and phase change was omitted in order to focus only on the convective mechanism. The channel is horizontal with a uniform-heat-generation upper wall and an adiabatic lower surface. A Lagrangian framework was adopted such that the computational domain surrounds the bubble and moves at the nominal bubble speed. The liquid around the bubble moves as a low-Reynolds-number unsteady laminar flow. The volume-of-fluid method was used to track the liquid/gas interface. This paper reviews the central results of this simulation regarding wake heat transfer. It then compares the findings regarding Nusselt number enhancement to a reduced-order model on a two-dimensional domain in the wake of the bubble. The model solves the advective-diffusion equation assuming a velocity field consistent with fully developed channel flow in the absence of the bubble. The response of the uniform-heat-generation upper wall is included. The model assumes a temperature profile directly behind the bubble which represents a well-mixed region produced by the passage of the bubble. The significant wake heat transfer enhancement and its decay with distance from the bubble documented by the simulation were captured by the reduced-order model. However, the channel surface temperature recovered in a much shorter distance in the simulation compared to the reduced-order model. This difference is attributed to the omission of transverse conduction within the heated surface in the two-dimensional model. Beyond approximately one bubble diameter into the bubble wake, the complex flow structures are replaced by the momentum field of the precursor channel flow. However, the properties and thickness of the heated upper channel wall govern the heat transfer for many bubble diameters behind the bubble.
Experiments with Rydberg atoms on a current-carrying atom chip

On one side, atom-chip experiments have demonstrated to be a versatile tool to study quantum physics in cold atoms systems. On the other side, Rydberg atoms have exaggerated properties that makes them good candidates to study quantum information and quantum simulations protocols. In this thesis both system are put together with the aim to study Rydberg physics (in particular atom-atom interaction) in an atom-chip experiment. Due to the exaggerated properties of Rydberg atoms they are very sensitive to electric fields. Thus, the combination of Rydberg atoms with surfaces can be challenging. Therefore a detailed characterization of the mentioned stray electric fields via the analysis of Stark-Zeeman maps is crucial. We employ two-photon Rydberg Stark spectroscopy of a micron-sized cloud of magnetically trapped ultracold rubidium atoms to characterize the electric fields near our atom-chip. Once we characterized the local electric fields we were able to study in more detail the effect of Rydberg excitation in the ultracold cloud of atoms. For instance we observed the formation of ultralong-range Rydberg molecules in our system. In these molecules a ground state atom is weakly bound to the Rydberg electron. We also attempted to observe the effect of Rydberg blockade in the system by looking at the characteristics of Rydberg spectra. Finally we studied the possibility of inducing rf transitions within a Rydberg state manifold in order to enhance our detection method and populate states that are not accessible directly with a two-photon laser transition.
Changes in the Heart Rate of Sniffer Dogs Trained for Detection of Lung Cancer

Background: Lung carcinoma is one of the most common malignancies worldwide. At present, unfortunately, there are no markers that would allow early identification of this tumor in the preclinical or early clinical stage. The use of sniffer dogs has been reported to show some promise in early diagnosis of this type of cancer Aim: This study aimed to evaluate the possibility of utilizing changes in the heart rate of sniffer dogs (which increases when finding a positive sample) in tumor detection. Methods: This double-blinded pilot study included two sniffer dogs. A chest strap was fastened on the dog’s chests for heart rate monitoring while they were examining samples and heart rate was recorded. Test parameters (sensitivity, specificity, positive and negative predictive values) were then calculated, evaluating performances based on (i) the dog’s indications according to their training and (ii) the changes in their heart rates. Results: Calculation according to the dog’s indications revealed an overall sensitivity of 95.2% accompanied by a specificity of 81.8%, a PPV of 93.7%, and an NPV of 85.7%, respectively. These results were not significantly different from those evaluated by heart rate; heart rate monitoring was, however, burdened with a relatively high proportion of invalid experiments in which heart rate measurement failed. When the method of calculation was changed from rounds to individual samples, the test parameters further increased. Conclusions: This pilot study confirmed the hypothesis that heart rate increases in trained sniffer dogs when encountering samples from tumor-positive patients but remains unchanged when only negative samples are present. The reliability of results based on heart rate increase is similar to that obtained by a dog’s indications and, if the limitation represented by technical issues is overcome, it could serve as a valuable verification method.
Analytical investigation of non‐local deformation‐mediated magneto‐electric coupling

The research on magneto‐electric materials is concentrated on multi‐ferroics and hard‐matter composites. However, rather recently soft composites also exhibiting pronounced magneto‐electric coupling entered the scene. Such composites are straight‐forward to manufacture and have cheap constituents compared to classical approaches. This contribution is concerned with an analytical estimation of a particular non‐local magneto‐electric coupling effect that exists regardless of the composite nature but relies on the softness of a magneto‐electric material.
On the Skein Theory of 0-framed Surgery Along the Trefoil Knot

In this dissertation, we will give a generating set of the Kauffman bracket skein module over the field Q(A) of 0-framed surgery along the trefoil knot. This generating set is described as a certain subset of a known basis for the skein module over Z[A±1] of the trefoil exterior.
Novel training algorithms for long short-term memory neural network

More recently, due to the enormous potential of long short-term memory (LSTM) neural network in various fields, some efficient training algorithms have been developed, including the extended Kalman filter (EKF)-based training algorithm and particle filter (PF)-based training algorithm. However, it should be noted that if the system is highly non-linear, the linearisation employed in the EKF may cause instability. Moreover, the PF usually suffers from the particle degeneracy. Therefore, the PF-based training algorithm may only find a poor local optimum. To solve these problems, an unscented Kalman filter (UKF)-based training algorithm is proposed. The UKF employs a deterministic sampling method; hence, there is no linearisation in it and it does not have the degeneracy problem. Moreover, the computational complexity of the UKF is the same order as that of the EKF. To further reduce the computational complexity, the authors propose a minimum norm UKF (MN-UKF) to obtain a good trade-off between performance and complexity. To the best of the authors’ knowledge, this is the first reported solution to this problem. Simulations using both benchmark synthetic signal and real-world signal illustrate the potential of the algorithms developed.
Cardboard Glass Gravel Concrete Dirt Grass Leaf

Materials make distinctive sounds when they are hit or scratched – dirt makes a thud; ceramic makes a clink. These sounds reveal aspects of an object’s material properties, as well as the force and motion of the physical interaction. In this paper, we introduce an algorithm that learns to synthesize sound from videos of people hitting objects with a drumstick. The algorithm uses a recurrent neural network to predict sound features from videos and then produces a waveform from these features with an example-based synthesis procedure. We demonstrate that the sounds generated by our model are realistic enough to fool participants in a “real or fake” psychophysical experiment, and that they convey significant information about the material properties in a scene.
An implementation framework for transformative gamification services

Gami ﬁ cation services are hailed as e ﬀ ective tools for in ﬂ uencing users ’ behaviours, increasing engagement, motivation, and enhancing learning. In the ﬁ eld of behaviour change, transformative outcomes have been reported for gami ﬁ cation services; with some conceptualisation undertaken regarding transformative gami ﬁ cation services. However, there is a lack of research on practical implementation of transformative gami ﬁ cation services. Also, previous studies have often isolated a single component of gami ﬁ cation and not discussed the synergistic e ﬀ ects and behavioural outcomes of the experiences that the combination of gami ﬁ cation elements can create. To bridge this gap, we provide an implementation framework for transformative gami ﬁ cation services. This is achieved by identifying di ﬀ erent components of transformative gami ﬁ cation from a social marketing and transformative service research (TSR) lens and their behavioural outcomes. To do this, we delve into game design, gami ﬁ cation and behaviour change literature and suggest a practical implementation framework which incorporates users ’ perspectives in the form of transformative values, user engagement types (play typologies), and consumption/service encounter experiences. This research contributes to gami ﬁ cation theory and practice by furthering the understanding of transformative gami ﬁ cation services in social marketing and TSR. It also provides behaviour change practitioners with detailed steps for implementation of such services aiming to create positive behavioural changes.
Speaking English as Experienced by Grade 7 Students: A Phenomenological Study

Speaking the English language can be difficult for some second-language learners. This study explored the difficulties and experiences of using the English language among selected Grade 7 students in one of the private institutions in Ozamiz City, Philippines. The study used the phenomenological research design. Six students served as the study's participants and were selected through the purposive sampling technique. Research-made Interview Guide was used in gathering the data. The Moustakas' steps of data analysis were used in analyzing the data gathered. The study yielded four themes, namely: speaking difficulties experienced, psychological effects during class, adverse outcomes of speaking difficulties, and coping with English-speaking difficulties. The participants experienced recurrent deficiencies in the target language and struggled to perform oral activities in their English classes. The English-speaking difficulties deeply impact language learners, but they endeavor to overcome their linguistic limitations. Thus, attaining a good proficiency in the English language entails recognizing the difficulties and exerting the necessary effort to overcome them.
Round Compression for Parallel Matching Algorithms

For over a decade now we have been witnessing the success of massive parallel computation frameworks, such as MapReduce, Hadoop, Dryad, or Spark. Compared to the classic distributed algorithms or PRAM models, these frameworks allow for much more local computation. The fundamental question that arises however in this context is can we leverage this additional power to obtain even faster parallel algorithms? A prominent example here is the maximum matching problem. It is well known that in the PRAM model one can compute a 2-approximate maximum matching in O (log n ) rounds. Lattanzi et al. [SPAA, ACM, New York, 2011, pp. 85--94] showed that if each machine has n 1+\Omega (1) memory, this problem can also be solved 2-approximately in a constant number of rounds. These techniques, as well as the approaches developed in the follow-up work, seem though to get stuck in a fundamental way at roughly O (log n ) rounds once we enter the (at most) near-linear memory regime. In this paper, we break the above O (log n ) round complexity bound even in the case of slightly sublinear memory per machine. In fact, our improvement here is almost exponential : we are able to deliver a (1 + \epsilon )-approximate maximum matching for any fixed constant \epsilon > 0 in O ((log log n ) 2 ) rounds. To establish our result we need to deviate from the previous work in two important ways. First, we use vertex-based graph partitioning, instead of the edge-based approaches that were utilized so far. Second, we develop a technique of round compression .
Sharp Bounds for the Second-Order General Connectivity Index of Hexagonal Chains

<jats:p>Given <mml:math xmlns:mml="http://www.w3. org/1998/Math/MathML" id="M1"><mml:mrow><mml:mi>H</mml:mi></mml:mrow></mml:math>, a hexagonal chain, we determine an expression of its second-order general connectivity index, denoted by <mml:math xmlns:mml="http://www.w3. org/1998/Math/MathML" id="M2"><mml:msub><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>χ</mml:mi></mml:mrow><mml:mprescripts /><mml:none /><mml:mrow><mml:mn fontstyle="italic">2</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow><mml:mrow><mml:mi>α</mml:mi></mml:mrow></mml:msub><mml:mo stretchy="false">(</mml:mo><mml:mi>H</mml:mi><mml:mo stretchy="false">)</mml:mo></mml:math>, in terms of inlet features of <mml:math xmlns:mml="http://www.w3. org/1998/Math/MathML" id="M3"><mml:mrow><mml:mi>H</mml:mi></mml:mrow></mml:math>. Moreover, by applying the method in integer programming theory, we completely determine the extremal chains with the minimal or maximal <mml:math xmlns:mml="http://www.w3. org/1998/Math/MathML" id="M4"><mml:msub><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>χ</mml:mi></mml:mrow><mml:mprescripts /><mml:none /><mml:mrow><mml:mn fontstyle="italic">2</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow><mml:mrow><mml:mi>α</mml:mi></mml:mrow></mml:msub><mml:mo stretchy="false">(</mml:mo><mml:mi>H</mml:mi><mml:mo stretchy="false">)</mml:mo></mml:math> over the set of hexagonal chains. </jats:p>
Selection and identification of thermophilic yeast strains in leachate from the organic waste heap in Phu Luong district, Thai Nguyen province, Vietnam

The study was carried out to isolate and select useful thermophilic yeast strains in the process of organic domestic waste treatment in Phu Luong - Thai Nguyen. Research results from 23 samples of rust have isolated 10 strains of yeast on YPG medium at 40 oC. Among them, 6 strains of yeast were selected with the ability to grow and develop in a wide temperature range from 20-45 oC. The results of identification combined with morphological, physiological, and biochemical characteristics of yeast strains showed that, out of 6 selected strains, there were 3 strains belonging to the genus Saccharomyces (Saccharomyces sp. TNY13.01, Saccharomyces sp. TNY22.01), Saccharomyces cerevisiae TNY13.09), 2 strains of the genus Candida (Candida sp. TNY23.01, Candida tropicalis TNY23.126) and 1 strain of the genus Papiliotrema (Papiliotrema laurentii TNY23.127). Among them, the identified strain Saccharomyces cerevisiae TNY13.09 has the ability to grow at 45, tolerates a wide pH range of 4.0– 8.5, has a positive catalase reaction, is capable of using a variety of carbon sources, and belongs to class I biosafety group. On that basis, Saccharomyces cerevisiae TNY13.09 has the potential to be further researched and applied as additional microbial inoculants to the organic waste heap.
Sure independence screening for real medical Poisson data

ABSTRACT The statistical modeling of big data bases constitutes one of the most challenging issues, especially nowadays. The issue is even more critical in case of a complicated correlation structure. Variable selection plays a vital role in statistical analysis of large data bases and many methods have been proposed so far to deal with the aforementioned problem. One of such methods is the Sure Independence Screening which has been introduced to reduce dimensionality to a relatively smaller scale. This method, though simple, produces remarkable results even under both ultra high dimensionality and big scale in terms of sample size problems. In this paper we dealt with the analysis of a big real medical data set assuming a Poisson regression model. We support the analysis by conducting simulated experiments taking into consideration the correlation structure of the design matrix.
Backwards Asymptotically Autonomous Dynamics for 2D MHD Equations

We consider the backwards topological property of pullback attractors for the nonautonomous MHD equations. Under some backwards assumptions of the nonautonomous force, it is shown that the theoretical existence result for such an attractor is derived from an increasing, bounded pullback absorbing and the backwards pullback flattening property. Meanwhile, some abstract results on the convergence of nonautonomous pullback attractors in asymptotically autonomous problems are established and applied to MHD equations.
Dynamics and transport of instabilities in magnetized quasi-Keplerian Taylor-Couette flows

The stability and transition to turbulence in canonical shear flows have since long been an outstanding scientific problem. One of the most exciting examples of shear flow is Keplerian motion of gas and dust in accretion disks. Although the Keplerian velocity profile is linearly stable, the presence of magnetic fields gives rise to the magnetorotational instability (MRI). MRI is considered one of the most powerful sources of turbulence in hydrodynamically stable quasi-Keplerian flows, however obtaining observational evidence of its operation is challenging. Although the linear stability of Keplerian flows with applied external magnetic fields has been studied for decades, the influence of the instability on the outward angular momentum transport, an inherent prerequisite for accretion to occur, is still far from understood. The aim of this thesis was to provide a better understanding of angular momentum transport and nonlinear properties of the MRI. Motivated by recent laboratory experiments, the MRI driven by an azimuthal magnetic field in an electrically conducting fluid sheared between two concentric rotating cylinders (Taylor–Couette flow) was explored. The instability was studied numerically with both linear stability analysis and fully resolved direct numerical simulations of the Navier–Stokes and induction equations. It was found that at low magnetic Prandtl numbers, as those in liquid metals, the laminar Couette flow becomes unstable to a wave rotating in the azimuthal direction and standing in the axial direction via a supercritical Hopf bifurcation. Subsequently, the flow features a catastrophic transition to spatio-temporal chaos which is mediated by a subcritical Hopf bifurcation. The results are in quantitative agreement with the PROMISE experiment and dramatically extend its realizable parameter range. Subsequently, the enhancement of angular momentum transport by turbulent stresses in the highly turbulent flow regimes was determined. One regime is dominated by magnetically triggered inertial waves, with transport mostly due to velocity fluctuations, and another by magnetocoriolis waves, where magnetic field fluctuations prevail. The magnetic Reynolds number defines the type of turbulence, with a crossover around the critical value of 100. The results give a comprehensive picture of transport enhancement by MRI spanning from low (as in liquid metals) to high (as in plasma) magnetic Prandtl numbers. In the latter case the existence of a finite-amplitude dynamo was demonstrated. This suggests that accretion disks can operate selfsustaining MHD-turbulence and thereby transport angular momentum efficiently without the need of considering imposed magnetic fields.
Pemanfaatan Blockchain dalam Konsep Sistem Rantai Pasok Pangan Halal: Studi Eksplorasi

Tujuan. Penelitian ini bertujuan untuk mengeksplorasi dua isu utama penelitian yaitu: (1) kegunaan dan peluang, serta (2) konsep penerapan aplikasi blockchain pada sistem rantai pasok pangan halal.Metode. Penelitian ini menggunakan pendekatan kualiatitatif dengan metode studi eksplorasi. Pengumpulan data dilakukan dengan kajian literatur, analisa data dengan mentemakan data penelitian yang menghasilkan rekomendasi Sistem Pasok Pangan Halal dengan Teknologi Blockchain.Hasil. Penelitian ini menghasilkan dua tema penelitian yaitu: (1) Manfaat dan Kegunaan Teknologi Blockchain pada Sistem Rantai Pasok Pangan Halal menghasilkan dua manfaat dan kegunaan yaitu transparansi dan aman serta efektifitas proses bisnis sistem rantai pasok pangan halan dengan blockchain. Hasil penelitian yang (2) adalah rekomendasi atas konsep penerapan aplikasi blockchain pada sistem rantai pasok pangan halal.Implikasi. Konsep sistem rantai pasok pangan halal berbasis blockchain sangat penting bagi para pemangku kepentingan yang menginginkan integrasi, dan transparansi sesuai persyaratan dari LPPOM MUI. Sehingga pangan halal yang dikonsumsi oleh konsumen bebas kontaminasi di sepanjang rantai pasokan.
Exponential-stability and super-stability of a thermoelastic system of type II with boundary damping

In this paper, the stability of a one-dimensional thermoelastic system with boundary damping is considered. The theory of thermoelasticity under consideration is developed by Green and Naghdi, which is named as ``thermoelasticity of type II''. This system consists of two strongly coupled wave equations. By the frequency domain method, we prove that the energy of this system generally decays to zero exponentially. Furthermore, by showing the spectrum of the system is empty under certain condition and estimating the norm of the resolvent operator, we give a sufficient condition on the super-stability of this thermoelastic system. Under this condition, the solution to the system is identical to zero after finite time. Moreover, we also estimate the maximum existence time of the nonzero part of the solution. Finally, we give some numerical simulations.
The use of Lightning Mapping Array data in WDSS-II

Lightning source data from the Oklahoma Lightning Mapping Array (LMA) has been ingested into NSSL’s Warning Decision Support System Integrated Information (WDSS-II) and is presented visually in several ways: as a dynamic three-dimensional plot of source data, as a dynamic three-dimensional grid of source densities and as various derived two-dimensional grids of source densities. Users can visualize the 3D structure of the incloud lightning densities, and its co-location with radar data and the various iso-therm levels. In this paper, we describe the processing of LMA data in WDSS-II and the creation of some multi-sensor products that use LMA data.