Miracle-dz/UniFAR-FTUs huggingface dataset:
A comprehensive model of backgate impedance dispersions in GaAs isolation structures

A comprehensive model explains low frequency reactive, resonant and negative resistance effects in backgate current flow in monolithic GaAs integrated circuits. In a sister paper experimental comparisons were made between structures prepared by MBE on undoped buffer layers at high and low temperatures and by ion implantation. The study employed GaAs MESFETs which were similarly prepared on the three substrates. These observations provide the basis for the model. In the case of the ion implanted and normally buffered structures the form of the susceptance frequency spectra depended on cathode size, dc bias and temperature and could include capacitive relaxation as well as inductive and capacitive behaviors separated by a resonance. The form of the variation of the conductance was closely associated and frequently included a frequency region within which there was negative small signal resistance. All of these effects have been explained in terms of electron trapping at trap planes located at the interface between the n-type active region and the isolation material. In the case of inductive and capacitive relaxations a single trapping process was sufficient but the negative resistance behavior makes the additional requirement that charge should be trapped sequentially at least twice. Mathematical modeling and computational simulations have been used to give support to the physical models. In the case of the ion implanted structures it was possible to demonstrate reasonable quantitative agreement between the model and experiment using trap DLTS data.
Safety and Efficacy of a MEURI Program for the Use of High Dose Ivermectin in COVID-19 Patients

Background In the absence of antiviral alternatives, interventions under research for COVID-19 might be offered following guidelines from WHO for monitored emergency use of unregistered and experimental interventions (MEURI). Ivermectin is among several drugs explored for its role against SARS-CoV-2, with a well-known safety profile but conflicting data regarding clinical utility for COVID-19. The aim of this report is to inform on the results of a MEURI Program of high-dose ivermectin in COVID-19 carried out by the Ministry of Health of the Province of La Pampa, Argentina. Methods COVID-19 subjects, within 5 days of symptoms onset were invited to participate in the program, which consisted in the administration of ivermectin 0.6 mg/kg/day for 5 days plus standard of care. Active pharmacosurveillance was performed for 21 days, and hepatic laboratory assessments were performed in a subset of patients. Frequency of Intensive Care Unit (ICU) admission and COVID-19-related mortality of subjects in the ivermectin intention to treat group were compared with that observed in inhabitants of the same province during the same period not participating in the program. Results From 21,232 subjects with COVID-19, 3,266 were offered and agreed to participate in the ivermectin program and 17,966 did not and were considered as controls. A total of 567 participants reported 819 adverse events (AEs); 3.13% discontinued ivermectin due to adverse events. ICU admission was significantly lower in the ivermectin group compared to controls among participants ≥40 year-old (1.2 vs. 2.0%, odds ratio 0.608; p = 0.024). Similarly, mortality was lower in the ivermectin group in the full group analysis (1.5 vs. 2.1%, odds ratio 0.720; p = 0.029), as well as in subjects ≥ 40 year- old (2.7 vs. 4.1%, odds ratio 0.655; p = 0.005). Conclusions This report highlights the safety and possible efficacy of high dose ivermectin as a potentially useful intervention deserving public health-based consideration for COVID-19 patients.
Development of a mechanistic-empirical model to characterize rutting in flexible pavements

Dramatic increases in the number and weight of vehicles have resulted in severe rutting on highways in Taiwan. The Taiwan Area National Freeway Bureau constructed an in-service test road in 1996 to investigate the effect of pavement structures and paving materials on pavement performance. A mechanistic-empirical rutting model was developed to account for material property changes in the progression of rutting over time and the cumulated compressive plastic strains of all layers on the basis of traffic loading. In addition, a three-dimensional, dynamic finite-element simulation was established to calculate pavement responses that were input into the rutting model for predicting permanent deformation. Traffic speed showed significant impact on vertical strains at the top of the surface layer, and its influence was consistent with those measured by other researchers. The rutting parameters in the model were calibrated using rut depths obtained from the field test, and the validation outcome showed that their predictions were in good agreement with measured ones. The results of this paper demonstrate that incorporating the mechanistic-empirical approach in the prediction of rutting is viable and provides valuable information on the contribution of each layer to permanent deformation in flexible pavements.
Citizen Journalism in Bangladesh and Its Legal Aspects

: Citizen Journalism is the foundation of journalism across the world. Also, Human’s instinctive virtue of curiosity, to know the unknown, to explore the unseen, and to gain knowledge about the undiscovered, has gotten us started on many great things over time and journalism is surely one of the bests of all. Citizen journalism is also known as public participatory, democratic, guerrilla, or straight journalism means ordinary people who are not professional journalists collecting and distributing information via the internet. This version of journalism may go extremely wrong if it is not monitored under lawful administration. It may also increase the vices of rumors. The paper argues for the monitoring of citizen journalism in Bangladesh in a way that doesn’t control freedom of expression. At the same, it shall not be the cause of rumors and various other wrongs.
NONLINEAR MOTION CONTROL OF MULTIPLE AUTONOMOUS UNDERWATER VEHICLES

Abstract This paper addresses the problem of steering a group of underactuated Autonomous Underwater Vehicles (AUVs) along given spatial paths, while holding a desired inter-vehicle formation pattern (coordinated path-following, abbreviated CPF). Exploiting Lyapunov-based techniques and graph theory, a decentralized control law is derived that takes into account the dynamics of the cooperating vehicles, the constraints imposed by the topology of the inter-vehicle communications network, and the cost of exchanging information. The CPF problem is divided into the motion control task of making each vehicle track a virtual target moving along the desired path, and the dynamic assignment task of adjusting the speeds of the virtual targets so as to achieve vehicle coordination. At the path-following level, the controller derived exhibits an inner-outer loop structure. Convergence and stability of the overall system are proved formally. Simulations results are presented and discussed.
The spectrum of clipped noise

The present report calculates in some detail the (intensity) spectrum to be expected for clipped (also called "limited") noise. Two cases are considered: (A), the clipping of an unmodulated noise band (DINA) [1] and (B) a carrier modulated by clipped noise. The computations are made for various shapes of noise bands before clipping, viz., 1) a uniform or rectangular structure, 2) a Gaussian distribution, 3) an "optical" (Lorentzian) shape factor of the type 1/[(v-v 0 )2+ δ2]. The simplest type of calculation to make is that for what we term "extreme clipping," wherein the limiting amplitude is very small compared to the rms amplitude before clipping. The mathematical theory for this is given in Section III, while Section IV develops the theory for clipping at an arbitrary level. The basic mathematical method, which is rather general and is useful, we believe, for a variety of noise problems, is presented in Section II and consists in utilizing a relation between the correlation function and the normal surface, along lines suggested by Rice [1]. The results of the calculation are discussed in Section I and are displayed in Figures 4-10 and Tables I and II. If the clipping is not down to more than the rms level before limiting (equivalent to clipping at about 1.4 times the rms level after clipping), there is practically no distortion of the spectrum. Even in the case of extreme clipping the wastage of power due to spoiling of the spectrum's uniformity is small, amounting to only 31 percent in (A) and 24 percent in (B). Of the 31 percent loss in (A), 19 percent is due to production of harmonics of the central frequency. Corresponding harmonics are absent in (B). Clipping is beneficial for jamming purposes in either (A) or (B) since it reduces the peak power requirements. In addition, in (B) it materially diminishes the wastage of power in the carrier frequency. These facts are demonstrated particularly clearly by Tables I and II. For instance, Table II shows us that in (B) the ratio of the energy in the noise sideband to that in the carrier is only 0.23 when the clipping level is twice the original rms noise level, but increases to 0.52 when these two levels are the same, and to 1.0 for extreme clipping. It is to be cautioned that the present report calculates only the (intensity) spectrum of the clipped noise, and does not deal with its effectiveness on a receiver, which we hope to discuss later from a quantitative standpoint [2]. We can, however, say qualitatively that if the receiver breadth is very small compared to the noise band, the received disturbance will have the same type of Gaussian fluctuation, and hence the same effectiveness as unclipped noise with the same spectral distribution. On the other hand, if the receiver is comparable with the noise band in width, there will be, due to the clipping, a tendency for a "ceiling" in the resultant deflection of the recording device, and under these conditions the utility of clipped noise for jamming is materially diminished.
An investigation of classifying the flow over rough surfaces into k- and d- type in turbulent channel flow

This thesis is concerned with the classification of roughness into k- and d- type in turbulent channel flow. Despite the practical importance of this type of flow, the literature review suggest that advancements in the field have been slow due to the difficulty of making accurate measurements close to the wall when using experimental methods. In recent years, numerical modelling has provided a good alternative to studying this type of flow. In this work, an Implicit Large Eddy Simulation (ILES) approach was developed to carry out numerical simulations for turbulent channel flow over rough surfaces. The application was developed based on the Finite Element Method and implemented using the Multi-Physics platform COMSOL. Verification and validation of the numerical model was carried out to asses the predictive capabilities of the model, including sensitivity analysis to quantify the uncertainty and comparison with results from literature to validate the model. In our analysis, we considered rough surfaces with square and triangular roughness elements with a constant roughness height and varying distributions of the roughness elements. The results demonstrated that the model is capable of resolving the coherent large eddy structures associated with the k- and d- type behaviours. The classification reported here is based on the coherent structures associated with the k- and d- type behaviours. Furthermore, we investigated the effects of roughness geometry on the k- and d- type behaviours. To this end, flow visualizations were used to study the interaction between the inner and outer layer of the flow. The results demonstrated that the geometry of the roughness elements has little effect on the coherent structures associated with the k- and d-type behaviours, these effects of the roughness geometry are confined to the inner region. However, the results show that the roughness geometry has a strong influence on the interaction between the inner and outer flow regions.
Review on engineering properties of MICP-treated soils

Microbial induced calcium carbonate precipitation (MICP), a sustainable and effective soil improvement method, has experienced a burgeoning development in recent years. It is a bio-mediated method that uses the metabolic process of bacteria to cause CaCO3 precipitation in the pore space of the soil. This technique has a large potential in the geotechnical engineering field to enhance soil properties, including mitigation of liquefaction, control of suffusion, etc. Multi-scale studies, from microstructure investigations (microscopic imaging and related rising techniques at micron-scale), to macroscopic tests (lab-based physical, chemical and mechanical tests from centimeter to meter), to in-situ trials (kilometers), have been done to study the mechanisms and efficiency of MICP. In this article, results obtained in recent years from various testing methods (conventional tests including unconfined compression tests, triaxial and oedometric tests, centrifuge tests, shear wave velocity and permeability measurements, as well as microscopic imaging) were selected, presented, analyzed and summarized, in order to be used as reference for future studies. Though results obtained in various studies are rather scattered, owning to the different experimental conditions, general conclusions can be given: when the CaCO3 content (CCC) increases, the unconfined compression strength increases (up to 1.4 MPa for CCC=5%) as well as the shear wave velocity (more than 1-fold increase in V_s for each 1% CaCO3 precipitated), and the permeability decreases (with a drop limited to less than 3 orders of magnitude). Concerning the mechanical behavior of MICP treated soil, an increase in the peak properties, an indefinite increase in friction angle and a large increase in cohesion were obtained. When the soil was subjected to cyclic/dynamic loadings, lower pore pressure generation, reduced strains, and increasing number of cycles to reach liquefaction were concluded. It is important to note that the formation of CaCO3 results in an increase in the dry density of the samples, which adds to the bonding of particles and may play a major part in the improvement of the mechanical properties of soil, such as peak maximum deviator, resistance to liquefaction, etc.
Improving the thermal reliability of large area solder joints in IGBT power modules

Due to power losses as well as alternating external operating conditions in IGBT power modules thermo-mechanical strain arises from the different coefficients of thermal expansion. Especially for Cu baseplates in the substrate-to-baseplate solder layer this cyclic straining leads to the formation and propagation of cracks. As a result, the thermal resistance between chip and heat sink increases with increasing number of cycles. In this paper the influence of numerous design and material parameters, such as solder material, thickness of the solder layer and substrate layout, on the long term reliability of large area solder connections is discussed.
EFEKTIVITAS MODUL PENCEGAHAN HIV/AIDS BAGI CALON PENGANTIN TERHADAP PENGETAHUAN DAN SIKAP

Salah satu kebijakan kota Bogor dalam mengatasi masalah HIV/AIDS dengan menetapkan Peraturan Daerah Kota Bogor No. 4 Tahun 2016 tentang pencegahan dan penanggulangan HIV/AIDS pada pasal 12 paragraph 3 tentang pencegahan penularan HIV/AIDS pada calon pengantin yang tertera pada pasal 13 ayat 3 yang berbunyi “setiap calon pengantin dirujuk ke Puskesmas untuk melakukan tes HIV/AIDS”. Kurangnya motivasi calon pengantin untuk konseling tes sukarela (KTS) bukan hanya dari kata Human Immunodeficiency Virus (HIV) tetapi juga banyak faktor seperti kurangnya pengetahuan calon pengantin tentang HIV, kurang support atau dukungan untuk melakukan KTS baik dari pasangan calon pengantin, tenaga kesehatan, tokoh masyarakat dan tokoh agama, dan menyadari dirinya rentan terhadap HIV/AIDS. Untuk mengetahui efektifitas modul pencegahan HIV/AIDS bagi calon pengantin di Kota Bogor terhadap pengetahuan dan sikap adalah tujuan dari penelitian ini. Sampel yang digunakan adalah consecutive sampling. Pengumpulan data menggunakan google form. Desain penelitian yang digunakan dalam penelitian ini adalah metode kuantitatif menggunakan bentuk quasi experiment nonrandomized control group posttest only design. Responden penelitian ini sebanyak 40 orang calon pengantin bertempat tinggal di wilayah Kota Bogor yang memenuhi kriteria inklusi. Penelitian ini dilakukan pada bulan Agustus sampai dengan Desember 2020 terhadap 40 responden dari masing-masing kelompok. Variabel independen adalah pengetahuan dan sikap, sedangkan untuk variabel dependennya adalah modul pencegahan HIV/AIDS bagi calon pengantin. Variabel diukur menggunakan kuesioner. Data diambil saart responden mengikuti kursus pranikah secara daring. Analisis data menggunakan uji statistik non parametrik yaitu Mann-Whitney sehingga terlihat perbedaan dari masing-masing kelompok. Terdapat perbedaan yang signifikan pada kelompok intervensi yang mendapatkan sosialisasi modul pencegahan HIV/AIDS memiliki pengetahuan dan sikap yang lebih baik dibandingkan pengetahuan dan sikap pada kelompok kontrol. Rekomendasi: perlu penelitian lanjutan setelah mendapat sosialisasi modul pencegahan HIV/AIDS yang mengacu kepada kesadaran calon pengantin untuk melakukan konseling dan tes sukarela sebagai upaya pencegahan HIV/AIDS pada pasangannya
Magnetic resonance imaging diagnosis of causes of cerebral palsy in a developing country: A database of South African children.

BACKGROUND Cerebral palsy (CP) is a common worldwide disabling disorder. However, data about prevalence and causes of CP in developing countries are deficient because of high cost and limited availability of magnetic resonance imaging (MRI), the gold standard neuro-imaging modality for evaluation and management of CP in neonates. OBJECTIVES To determine the frequency of CP causes in children with suspected hypoxic ischaemic injury (HII) involved in medicolegal litigation in South Africa based on MRI report findings. METHODS A total of 1 620 MRI reports were categorised into HII, non-HII and normal MRI. None of the patients had prior neuro-imaging records. HII reports were sub-classified according to pattern of brain injury into basal ganglia-thalamus (BGT), watershed (WS), combined BGT-WS, periventricular leukomalacia (PVL) and multicystic encephalomalacia. Non-HII diagnoses were sub-classified into strokes, congenital malformations, kernicterus, hydrocephalus, haemorrhages, atrophies, metabolic causes and infections. RESULTS The median age was 6 years. HII reports (n=1 233; 76.1%) showed BGT in 447 (27.6%), WS in 266 (16.4%), combined BGT-WS in 335 (20.7%), PVL in 58 (3.6%) and multicystic in 127 (7.8%). Non-HII diagnoses (n=255; 15.7%) showed 78 (4.8%) congenital malformations, 50 (3.1%) atrophies, 35 (2.1%) kernicterus, 23 (1.4%) strokes, 12 (0.8%) haemorrhages, 14 (0.9%) hydrocephalus, 36 (2.1%) metabolic and 7 (0.5%) infections. Normal exams were 132 (8.2%). CONCLUSIONS Despite being performed a relatively long time - median of 6 years - after the suspected perinatal HII, MRI yielded a diagnosis in 92% and showed that only 76% were due to HII, and more importantly, that there was a preterm HII pattern of injury in 15%, which when added to the 16% of non-HII cases, could potentially save on litigation in a total of 31% of cases that are unlikely to be related to malpractice. MRI should be performed wherever possible in CP cases, even if no imaging exam was performed in the perinatal period.
Barriers and Drivers of Public Preventive Behavioral Responses to COVID-19 Outbreak: Evidence from Iran

Background: When an epidemic outspreads, the society engagement seems essential to make sure of the population’s preparedness for taking individual precautions. Objectives: The primary objective of this study was to examine public’s preventive behavioral responses to protective behaviors during the COVID-19 pandemic to provide a description of conceptual frameworks for deeper understanding of these behaviors. Methods: A self-administrated questionnaire was used in this online survey through social networks during March 19th to 26th, 2020 (n = 2550). A Likert scoring scale was employed to investigate barriers and drivers affecting the participants’ preventive behaviors. Using personal protective equipment and good hand hygiene practices were identified as person-based measures. Social distancing and the restriction of social and economic activities during the past two months were determined as community-based measures. Univariate logistic regression and multiple - logistic regression were used to identify and assess influencing factors. Results: The study results indicated that 2426 (95.1%) of the participants intended to restrict their social and economic activities, and 1968 (72.2%), 1637 (64.2%), and 2492 (97.7%) persons intended to observe social distancing, use personal protective equipment, and have good hand hygiene, respectively. The most important barriers for preventive behaviors were the lack of risk perception, economic and financial barriers, lack of access, and cultural barriers, respectively. The perceived benefit was among the most significant driver. Intention for person-based measures was less affected by demographic and economic characteristics in comparison with community-based measures. Conclusions: Considering the substantial impact of preventive behaviors on managing COVID-19 epidemic, this study findings have remarkable implications for governments to manage future communications as well as interventions during this ongoing outbreak and subsequent national risk events.
Shakedown of Subgrade Soil under Repeated Loading

A new model for predicting the performance of a subgrade during soil compaction by rollers as a function of contact pressure and the strength characteristics of soils was developed. The model can be used to develop improved methods of pavement design, considering that the accumulation of plastic strains may continue under additional load repetitions or may cease to increase with time, indicating adaptation or shakedown conditions. To develop the mechanistic model of a subgrade, the homogeneous semi-infinite elastoplastic half-space under repeated loading was considered. By using a Mohr-Coulomb failure criterion, the boundary loads for which shakedown conditions or the steady state will be attained were determined. The residual horizontal normal stresses in the half-space were calculated and were shown to be in agreement with the measured distribution with depth. The theoretical and experimental results as they apply to soil compaction and pavement design problems are discussed. The required compaction contact pressure and the thickness of the compacted zone are estimated. The structural pavement design approach, considering residual normal stresses in a subgrade, is presented.