Miracle-dz/UniFAR-FTUs huggingface dataset:
Investigations on Forced Convection in Compact Passages With Surface Irregularities

Two-dimensional, fully developed, convective heat transfer in compact passages is investigated numerically, incorporating the effects of the surface irregularities, to analyze the influence of these irregularities on fluid flow and heat transfer. This analysis helps to bring out the differences in the performance evaluation if regular cross sections are assumed in analyzing compact and mini channels. Forced convection in compact passages with an apparent rectangular shape is analyzed using a finite-difference method. The calculation is validated experimentally using Michelson interferometry. The numerical results for the channel, incorporating surface irregularities, are compared with those assuming a regular cross-sectional geometry. The results indicate that the coefficient of friction and the Nusselt number calculated for channels, considering the irregular cross section, are less than those predicted using an assumption of regular geometry. The results provide some insight into the reasons for the observed deviations in the comparisons. The observations are attributed to the influence of the surface irregularities on the relative dominance of the surface area to the cross-sectional area, which gets pronounced in compact passages. The findings suggest that some of the observed deviations in the performance of compact passages, compared to theoretical results, may be due to the use of regular geometries to define domain shapes while performing theoretical analysis.
MULTI-INPUT BIDIRECTIONAL DC-DC CONVERTERS FOR SHIP ELECTRICAL SYSTEM: A REVIEW

A multi input converter topology are combination of DC to DC converters which are used improve the reliability, flexibility and efficiency of the overall system through the structure of the converter and to achieve better monitoring on the energy management resources . Therefore multi-input dc-dc converters will be of particular interest of a lot of applications such as micro grid, energy storage system, hybrid power system, electric and hybrid electric vehicles, satellite system, etc. Different topologies have been proposed to combine different types of renewable energy sources as diversion increase the utilization of renewable energy sources such as photovoltaic panels which have the advantage of dc current and voltage characteristics and can be integrated through multi-input DC-DC converters . There are two categories for MI topologies: non-isolated and isolated, the non-isolated topologies are based on electrically connected circuit (ECC) and the isolated topologies are based on magnetically connected circuit (MCC) . This paper reviews developments and new trends happening in the area of multi input controllers (MIC) which can be of use in a hybrid ship electrical system. Various types of MIC’s are studied. Various types of isolated and non-isolated topologies are discussed.
YOLO-based Obstacle Avoidance for Drones Christof

One basic requirement for autonomous operation of UAVs is obstacle avoidance. Because of the strict power and weight constraints of UAVs, traditional sensors like LiDAR and ultrasound are often omitted in favour of a visual camera sensor. This thesis presents a method for obstacle avoidance utilising only these common, versatile sensor systems by using a deep learning (DL) approach, which aims to show the validity of using Convolutional Neural Networks (CNN) object detectors in the obstacle avoidance pipeline. The YOLOv4 object detector is used to generate bounding boxes around possible obstacles. These located obstacles are tracked and their sizes are compared in subsequent frames. The size ratio values gathered determine if a detected obstacle must be avoided. The proposed method is evaluated and compared against a previous non-DL SIFT-based method in various real-life obstacle avoidance scenarios. Here, results show an avoidance accuracy of 88 . 7% compared to 63 . 3% of the previous work. The proposed method performs on par with the previous work in a simple, single object scenario where accuracy reached 90%. Furthermore, results from more realistic scenarios including multiple objects and textured backgrounds show signiﬁcant improvements in accuracy from 71 . 0% to 90 . 0% and from 18 . 3% to 83 . 3% respectively. Lastly, the validity of using obstacle class labels gathered from the YOLOv4 network in obstacle avoidance was investigated, showing an increase in avoidance accuracy from 40 . 0% to 90 . 0% in the selected scenario.
The Role of ICT-Based Monitoring and Evaluation Systems in Infrastructural Development in County Governments: Empirical Evidence from Machakos County, Kenya

There exists knowledge gap in analysis of the influence of the general ICT-based M&E systems in county governments with a focus on data analysis and timely presentation to stakeholder, there an empirical gap in physical health infrastructural, road infrastructural development, market infrastructural development and sports infrastructural development ICT-based M&E. This study tried to fill the gap in knowledge by answering a question on what the role of ICT-based monitoring and evaluation systems in infrastructural development in county governments? The study used the Realist Evaluation Theory coupled with a descriptive design. The study was conducted in Machakos County, one of the 47 counties in the republic of Kenya with a target of both internal and external M&E contractors of the Machakos County Government since 2013 to 2022. The study used purposive sampling technique and census to select the study participants. Two forms of questionnaires were used to collect quantitative data; one for ICT departments and the other for M&E department of the County Government of Machakos. Interviews were used to collect qualitative data from the Heads of ICT and Project and Delivery M&E departments. The instruments were piloted at the county government of Kitui. Content validity of the instruments were assessed by experts while reliability was determined using Cronbach’s Alpha to ascertain items’ internal consistency (yielding r of at least 0.75). Descriptive and inferential statistics were used to analzyed quantitative data while the qualitative data was analzyed thematically. The study found that information and communication technology improvements had often led to new ideas. Because of technological progress, there were new methods, tools, and ways of doing things, as well as new opportunities and problems in infrastructural development in Machakos county government. In the construction industry, amenities like roads, bridges, and buildings were equipped with electronic sensors that could be accessed from afar and give information about access. Monitoring and evaluation (M&E) systems should be used by all sectors in the county to keep track of project progress, measure and evaluate project results.
IT Value Analysis by Resource-Based View Theory: The Case Study of PT. Telekomunikasi Indonesia, Tbk.

It’s believed that IT spending has influenced business performance. This departs from a theory, which stated that resources owned by business organizations have close relationship to levels of the business competitive advantage as Resource-Based View (RBV) theory proposes. To confirm this theory, a case study is performed for PT. Telekomunikasi Indonesia, Tbk. , the largest telcos industry in Indonesia. Researched data refer to Telkom Annual Report published between 2005 and 2012. The study focuses on data reflecting the relationship between IT spending and business performance. Findings show that IT spending has had a positive correlation to Telkom IT revenue. Likewise, metric-based performances such as ROA, ROE, Tobin’s q, and MVA have shown positive values, which strengthen the hypothesis above that the managed resources are in line with firm’s profitability, effectiveness, and total-amount value created. Telkom IT resources referring to RBV are then analyzed in terms of IT capability, IT competence, and competitive advantage that lead to be the IT value model. To sum up, the case study result indicates that IT value has definitely affected Telkom business performance. However, it is necessary to enlarge the case study to the other similar industry or the different one.
Thermal Conductivity and Thermal Radiation Properties of UO 2

More than 300 publications have been revised for studying the thermal conductivity and the thermal radiation properties of UO2. The temperature, the porosity, the uranium to oxygen ratio and irradiation effects have an important influence on the thermal conductivity. The thermal conductivity of stoichiometric UO2 with nearly theorectical density is well known up to the melting point with a maximum uncertainity of ± 15%. Relations can be established to calculate the conductivity of porous UO2. The correlation between the conductivity and the Ö/U ratio could not be described analytically but the qualitative dependence is evident. Only a few publications could be found on thermal radiation properties of UO2; most of them are investigating the radiation transport through solid fuel. Emittance data are therefore quite speculative. The total emittance and the spectral emittance might be approximately 0.9, and not significantly dependent on temperature and porosity or surface roughness.
Disease-Modifying Antirheumatic Drugs in the Treatment of Autoimmune Inner Ear Disease: A Systematic Review and Meta-Analysis of Auditory and Vestibular Outcomes

Objective To answer the following question: In patients with primary autoimmune inner ear disease (AIED), (population) what impact do disease-modifying antirheumatic agents (DMARDs) (intervention) when compared with no treatment or corticosteroids (comparison) have on auditory and vestibular outcomes (outcome)? Study Design Systematic review and meta-analysis. Data Sources According to PRISMA guidelines, PubMed, Scopus, CINAHL, and Cochrane Library databases were searched from inception to March 10, 2022. Study Selection Studies of patients receiving DMARDs for the treatment of AIED were selected for review. Case reports, phase I/II trials, studies of patients with secondary AIED, and studies of AIED patients receiving solely corticosteroids were excluded. Data Extraction Primary outcomes were pure-tone audiometry and speech discrimination scores at baseline and after DMARD treatment. Secondary outcomes were rates of subjective audiovestibular complaints and rates of adverse reactions. No objective vestibular outcomes underwent meta-analysis. Data Synthesis Mean differences were calculated using RevMan 5.4. Heterogeneity was assessed with the Q test and I2 statistic. Pooled prevalence rates of audiovestibular symptoms were expressed as a percentage with 95% confidence intervals. Results Ten studies with a total of 187 patients were included. Treatments included methotrexate, etanercept, azathioprine, anakinra, cyclophosphamide, rituximab, and infliximab. Mean treatment duration was 10.8 ± 22.2 months and mean follow-up was 13.7 ± 8.1 months. The pure-tone audiometry and speech discrimination scores mean differences between baseline and post-DMARD were −2.1 [−4.1, −0.1] dB and 13.9 [8.5, 19.4] %, respectively. Seven studies reported 38 adverse events, four of which were classified as serious. Conclusion DMARDs showed statistically significant improvement in auditory outcomes, as well as subjective symptoms, with relatively low rates of adverse events. They warrant further exploration to better compare with corticosteroids.
Compact and High Selectivity Dual-Band Bandpass Filter Using Nested Dual-Mode Defected Ground Structure Resonators

A novel type of compact and high selectivity dual-band bandpass filter (BPF) using nested dual-mode defected ground structure resonators (DDGSRs) is proposed in this paper. Using the structure parameters of the nested DDGSRs, dual-band BPF can be realized with a simple feed mechanism. Meanwhile, four transmission zeros and a wide upper stopband are generated simultaneously to achieve high selectivity. An experimental dual-band BPF located at 2.3 and 3.3 GHz is designed and fabricated. The measured results agree well with the simulated ones.
A phenomenological study on public school leadership in a hybrid workspace

As a form of adjustment to operational drawbacks set off by the Covid-19 pandemic, Head Teachers or department leaders in Philippine secondary schools resumed work in a hybrid setting. This study delved into the leaders’ experience reporting on-site and supervising remote teams. The researchers gathered qualitative data and explored it through thematic analysis. As a result, three significant themes emerged, which helped the researchers conclude that the condition influenced the virtual and personal relations of the school leaders. It was also apparent that the circumstances called for the necessary reskilling and upskilling of middle managers, and adaptive measures in leadership and communication could be useful in a hybrid setting.
Performance simulation for LCR of MIMO Multi-branch SC Diversity System in α-µ fading and α-µ interference channel

- In order to improve the overall performance of the network in 5G telecommunication networks, Multiple Input and Multi Output Technology (MIMO) is applied. In this paper, the mean number of Level Crossing Rate (LCR) of MIMO systems with L-branch selection combining (SC) receiver is analyzed. During signal transmission, its distortion occurs due to low α-μ fading and α-μ co-channel interference (CCI) effects. Additionally, we applied an accelerated graphics processing unit (GPU) simulation to plan a QoS-efficient 5G mobile network in a smart city. This approach in combination with linear optimization and deep learning significantly optimizes the LCR calculation speed for the observed communication system type, while providing efficient planning - reducing costs, but maximizing performance.
Correspondences to abelian varieties I

When S is an algebraic scheme, and X! S and Y! S proper schemes over S, we define the notion of correspondences from X to Y over S. And when Y! S is a relative abelian scheme and X is a normal variety, we give a charac- terization for a correspondence from X to Y over S to be a graph of some morphism X! Y over S, which is a generalization of the result for classical correspondences in (4).
Toppling of computer-type equipment under base excitation

An analysis is given of the statistical and probabilistic properties of the random time at which a piece of essential equipment, such as a computer, may topple under base excitations. The equipment is modeled as a rigid block, and the base accelerations are modeled as white noises in horizontal and vertical directions. The cases of a free-standing block and an anchored block are both considered. The white-noise idealization resembles the most intense portion of ground acceleration in a seismic event, which is an acceptable simplification provided that the correlation times of actual base excitations are short compared with the dominant quasi-periods of the induced rocking motion. It is shown that the presence of vertical excitation about one-half the level of horizontal excitation may increase the probability of toppling by 30–40%, and that larger blocks are more stable than the smaller ones of the same geometrical proportion. The analysis is applicable to such objects as monuments, storage tanks, and certain types of tall buildings.
Représentations parcimonieuses et apprentissage de dictionnaires pour la compression et la classification d'images satellites

Cette these propose d'explorer des methodes de representations parcimonieuses et d'apprentissage de dictionnaires pour compresser et classifier des images satellites. Les representations parcimonieuses consistent a approximer un signal par une combinaison lineaire de quelques colonnes, dites atomes, d'un dictionnaire, et ainsi a le representer par seulement quelques coefficients non nuls contenus dans un vecteur parcimonieux. Afin d'ameliorer la qualite des representations et d'en augmenter la parcimonie, il est interessant d'apprendre le dictionnaire. La premiere partie de la these presente un etat de l'art consacre aux representations parcimonieuses et aux methodes d'apprentissage de dictionnaires. Diverses applications de ces methodes y sont detaillees. Des standards de compression d'images sont egalement presentes. La deuxieme partie traite de l'apprentissage de dictionnaires structures sur plusieurs niveaux, d'une structure en arbre a une structure adaptative, et de leur application au cas de la compression d'images satellites en les integrant dans un schema de codage adapte. Enfin, la troisieme partie est consacree a l'utilisation des dictionnaires structures appris pour la classification d'images satellites. Une methode pour estimer la Fonction de Transfert de Modulation (FTM) de l'instrument dont provient une image est etudiee. Puis un algorithme de classification supervisee, utilisant des dictionnaires structures rendus discriminants entre les classes a l'apprentissage, est presente dans le cadre de la reconnaissance de scenes au sein d'une image.
The effects of ionospheric outflow on ICME and SIR driven sawtooth events

Magnetosphere sawtooth oscillations have been observed during interplanetary coronal mass ejection (ICME) events, when the solar wind conditions are relatively steady, and during periods when the interplanetary magnetic field (IMF) fluctuates between northward and southward, as during interplanetary stream interaction regions (SIR). The impact of ionospheric outflow on the ICME‐driven 18 April 2002 and SIR‐driven 24 October 2002 sawtooth events is investigated using a multifluid adaptation of the Lyon‐Fedder‐Mobarry global simulation. The mechanisms that generate the sawtooth oscillations are investigated by comparing a baseline simulation without outflow and a simulation that includes an O+ outflow model. The ionospheric outflow is regulated by a statistical relationship between Alfvénic Poynting flux and O+ ion outflow flux. In the baseline simulation for the 18 April 2002 ICME‐driven event, one substorm is observed that is generated by the southward turning of the IMF, after which the magnetosphere‐ionosphere system settles into a quasi‐steady convection mode. When outflow is included, quasi‐periodic substorms are observed suggesting that the sawtooth oscillations are generated internally by the effects of the O+ ions. In contrast, during the 24 October 2002 SIR‐driven event, quasi‐periodic substorms are generated regardless of whether outflow is included or not. For this event, the generation and triggering of the substorms is controlled by the external driving of the solar wind. For both events, when outflow is included, the signatures of the substorms are more intense and are more noticeable across a wider range of local times than in the baseline simulations.
10Gb/s direct modulation of widely tunable V-cavity-laser with chirp managed laser technology

We report direct modulation results in a simple and compact widely tunable V-cavity laser. Chirp managed laser technology has been successfully applied to the V-cavity laser with an optical spectrum reshaping filter. The tunable V-cavity-laser employs a half-wave coupler to obtain single-mode operation with high side-mode suppression ratio and the Vernier effect to extend its tuning range. It does not require any grating structure and regrowth steps. In this experiment, we achieved single-electrode controlled wavelength tuning of about 18 channels at 100GHz spacing with a fixed temperature, and 32 channels using 2 temperature settings. Well-open eye diagrams with extinction ratio above 4.3dB in all channels are observed when the laser is directly modulated at 2.5Gb/s. Although the measured small-signal frequency response is only about 5.7GHz, more than 6.7dB extinction ratio under 10Gb/s modulation rate is achieved by using the chirp managed laser technology with an optical spectrum reshaping filter placed after the output of the laser to convert the frequency chirp accompanying the direct modulation to amplitude modulation. The advantages of compactness, fabrication simplicity, easy wavelength control algorithm, and simple direct modulation offer great potential for the chirped managed V-cavity laser to be used in low-cost WDM links.
Design of Optimal Petri Net Controllers for Disjunctive Generalized Mutual Exclusion Constraints

In this paper, a type of specifications called OR-AND Generalized Mutual Exclusion Constraints (GMEC) for place/transition nets is defined. Such a specification consists of a disjunction of conjunction of several single GMECs, i.e, the requirement is that, at any given time, the controlled system should satisfy at least one set of conjunctive GMECs. We show that a bounded OR-AND GMEC can be enforced by a special control structure composed by a set of AND-GMEC monitor places plus a switcher that determines the current active ones. We also show that such a simple control structure can be modified to ensure maximal permissiveness. This approach can be used in the framework of supervisory control in Petri nets.
Valentine’s extensions of Tietze’s theorem on convex sets

New proofs are given for Valentine's extensions of Tietze's theorem on convex sets. Valentine in [1] proved the following two extensions of Tietze's theorem on convex sets. THEOREM 1. Let S be a closed connected subset of Rd such that S has at most n points of local nonconvexity. Then S is an L,+? set. THEOREM 2. Let S be a closed connected subset of Rd such that the points of local nonconvexity of S can be decomposed into n convex sets. Thlen S is an L2n+1 set. The purpose of this paper is to give new proofs of these theorems. The proofs depend upon the following two lemmas. LEMMA 1. Let S be a subset of Rd. Let x, y E S and suppose l is an arc from x to y of minimal arc length in S such that each point of I is a point of local convexity of S, except possiblyfor x andy. Then 1= [xy], the closed line segment from x to y. LEMMA 2. Let S be a closed connected subset of Rd, ii'hich has at least one point of local nonconvexity. Then given x eS there exists a point p of local nonconvexity of S such that [xp] e S. The proof of Lemma 1 is easy and is omitted. The proof of Lemma 2 is in Valentine [1]. We only prove Theorem 2, and then it will be clear how to prove Theorem 1 using the same method. PROOF OF THEOREM 2. Let {C1,. ** Cn3 be the n convex sets into which the points of local nonconvexity can be decomposed. Now let z E S. Define S(z) as (tIt -E S and [zt] c S} and define S(Ci) as UZEc, S(z). Clearly S(C) is an L3 set. Lemma 2 implies S= U=lJ S(C). The fact that S is connected then implies that S is an L3n set. Thus, given x, y E S, there exists an arc from x to y in S of finite arc length, and hence there exists an Received by the editors November 24, 1971. AMS 1970 subject classifications. Primary 52A20; Secondary 52A15. ( American Mathematical Society 1972
Normal stress and diffusion in a dilute suspension of hard spheres undergoing simple shear

The complete set of normal stresses in a dilute suspension of hard spheres undergoing simple shear at low Reynolds number is calculated using a path integration approach for the cases where the concentration is uniform and where a small gradient in concentration is present. As expected, the normal stresses are seen to be a strong function of es=2(b−a)/a, where b is the hard sphere radius and a is the particle radius. The normal stress differences N1 and N2, are negative while the osmotic pressure is large and positive, with Π>|N2| and N1→0 as es→∞. For es≪1, the asymmetry in the pair distribution function due to a depletion of particles in the extensional side of a pair interaction leads to |N1|>|N2|. On the other hand, for es→∞, the additional stresslet induced when hard sphere radii touch dominates the stress generated in the suspension, and N2 becomes the prevailing normal stress difference. The self and gradient diffusivities are calculated using da Cunha and Hinch’s [J. Fluid Mech. 309, 211 (1996)] t.