bluuebunny/crossref_metadata_2025 huggingface dataset:
Approximation and error analysis of forward–backward SDEs driven by general Lévy processes using shot noise series representations
Authors: Massing Till
Published: June 2023

We consider the simulation of a system of decoupled forward–backward stochastic differential equations (FBSDEs) driven by a pure jump Lévy process L and an independent Brownian motion B. We allow the Lévy process L to have an infinite jump activity. Therefore, it is necessary for the simulation to employ a finite approximation of its Lévy measure. We use the generalized shot noise series representation method by [26] to approximate the driving Lévy process L. We compute the Lp error, p ≥ 2, between the true and the approximated FBSDEs which arises from the finite truncation of the shot noise series (given sufficient conditions for existence and uniqueness of the FBSDE). We also derive the Lp error between the true solution and the discretization of the approximated FBSDE using an appropriate backward Euler scheme.
Die Beteiligung von Patient*innen an der Entwicklung von
Leitlinien in der Klinischen Medizin. Ein selektiver Ländervergleich in
narrativer Übersicht
Authors: Kiese-Himmel Christiane
Published: June 2023

Ziel Eine klinische Praxis-Leitlinie (LL) soll die Versorgung von
Patient*innen optimieren, indem sie auf Basis der besten
verfügbaren Forschungsergebnisse und praktischen Erfahrungen Diagnostik-
oder Behandlungspfade empfiehlt. Daher müssen auch Bedürfnisse
und Präferenzen von Patient*innen und deren Angehörigen
einfließen. Anhand eines selektiven Ländervergleichs werden
Regularien und Standards der Einbeziehung von Patient*innen in die
LL-Entwicklung untersucht.

Methode In Form eines narrativen Reviews werden Informationen aus
öffentlich zugänglichen Websites und
LL-Entwicklungshandbüchern aus dem Vereinigten Königreich (UK),
den USA, Kanada und Australien miteinander verglichen und diskutiert.

Ergebnisse Im UK sind in allen Gremien zur LL-Entwicklung und
während allen Stufen des Entwicklungsprozesses verbindlich mindestens
zwei Personen aus dem Kreis von Patient*innen oder der
Öffentlichkeit vorgeschrieben. Die National Academy of Medicine der USA
empfiehlt die aktive Teilnahme von Patient*innen mit
krankheitsspezifischen Erfahrungen sowie von Patientenvertreter*innen
aus der Öffentlichkeit an LL-Entwicklungsgruppen. Die Canadian Task
Force on Preventive Health Care möchte die Präferenzen von
Patient*innen vor allem bei der Entwicklung der endgültigen
LL-Empfehlungen und der Prüfung der Benutzerfreundlichkeit beteiligen.
In Australien erhalten LL die Zustimmung bzw. das Gütesiegel des
National Health and Medical Research Council, wenn mindestens ein*e
Patientenvertreter*in nachweisbar Mitglied des LL-Gremiums gewesen ist
und am gesamten Prozess der LL-Entwicklung beteiligt war.

Schlussfolgerung Der selektive Ländervergleich zeigt, dass die
Einbindung von Patient*innen bei der LL-Entwicklung bzw. deren
Verbindlichkeit stark variiert und es keine einheitlichen Standards
hierfür gibt. Viele Fragen der Einbindung sind ungeklärt, und es
wird besonderer Sensibilität bedürfen, um die Lebenswelt von
Patient*innen/Laien und medizinisches System gleichberechtigt
zusammenzuführen.
Considerations for Functional Nasal Surgery in the Obstructive Sleep Apnea Population
Authors: Coviello Caitlin , Sivam Sunthosh Kumar
Published: June 2023

Obstructive sleep apnea (OSA) and nasal obstruction are common in the general population and frequently treated by otolaryngologists and facial plastic surgeons. Understanding the appropriate pre-, peri-, and postoperative management of OSA patients undergoing functional nasal surgery is important. OSA patients should be appropriately counseled in the preoperative period on their increased anesthetic risk. In OSA patients who are continuous positive airway pressure (CPAP) intolerant, the role of drug-induced sleep endoscopy should be discussed with the patient, and depending on the surgeon's practice may prompt referral to a sleep specialist. Should multilevel airway surgery be indicated, it can safely be performed in most OSA patients. Surgeons should communicate with the anesthesiologist regarding an airway plan given this patient population's higher propensity for having a difficult airway. Given their increased risk of postoperative respiratory depression, extended recovery time should be given to these patients and the use of opioids as well as sedatives should be minimized. During surgery, one can consider using local nerve blocks to reduce postoperative pain and analgesic use. After surgery, clinicians can consider opioid alternatives such as nonsteroidal anti-inflammatory agents. Neuropathic agents, such as gabapentin, require further research in their indications for managing postoperative pain. CPAP is typically held for a period of time after functional rhinoplasty. The decision on when to restart CPAP should be individualized to the patient based on their comorbidities, OSA severity, and surgical maneuvers performed. More research would provide further guidance in this patient population to shape more specific recommendations regarding their perioperative and intraoperative course.
Identification of Bacterial Isolates and Their Antimicrobial Susceptibility Pattern from Wound/Pus Sample in a Tertiary Care Hospital, Gwalior, India
Authors: Rajput Kamini , Johri Sonia , Goyal Anju
Published: June 2023

Objective

The goal of this investigation was to look at the frequency and dispersal of bacteria isolated from pus/wound, as well as their susceptibility patterns.

Materials and Methods

A study was conducted on 175 patients who provided pus and/or wound discharge samples in different wards (outpatient department or inpatient department). MacConkey agar and blood agar plates were immediately inoculated with samples and incubated at 37°C for 24 hours. The Gram stain and biochemical tests were used to identify all isolates after incubation. Kirby–Bauer's disc diffusion method was used to perform sensitivity tests on Mueller–Hinton agar plates.

Results

This study covered 175 patients, with a bacterial isolation rate of 102 (58.28%). Males outnumbered females in the samples (M:F = 1.8:1), with a median age of 45 years as majority were in the age group of 40 to 60 years which was 41 (40.20%). Total 90.1% samples showed monomicrobial infection, whereas 9.8% showed polymicrobial infection, and total 112 bacterial strains were isolated.

Conclusion

Escherichia coli was the most prevalent isolate in present investigation, followed by Pseudomonas aeruginosa. Chloramphenicol is the only antibiotic which is effective for both gram-negative bacilli and gram-positive cocci. This report's susceptibility statistic may be worth considering for developing empiric treatment regimens for pyogenic infections.
Hypogonadism among Type 2 Diabetes Mellitus Patients with Male Erectile Dysfunction
Authors: Kadhim Dhahir J. , Almomin Ammar MS , Mansour Abbas A.
Published: June 2023

Introduction Testosterone levels and erectile function are known to decline as men age, leading to hypogonadism and erectile failure. Men with type 2 diabetes mellitus (T2DM) have a high prevalence of hypogonadism and erectile dysfunction. We aimed to estimate the prevalence of hypogonadism in T2DM patients complaining of erectile dysfunction.

Patients and Methods A cross-sectional study was conducted at Specialized Diabetes, Endocrine, and Metabolism Center from early September 2021 to the end of January 2022. The study included 115 fully anonymized randomly selected patients. Patients with diabetes were assessed for erectile dysfunction through a questionnaire derived from “The International Index of Erectile Function (IIEF).” Additionally, hypogonadism has been diagnosed with serum testosterone levels lower than 264 mg/dL according to the Endocrine Society 2018 criteria for the diagnosis of male hypogonadism.

Results The average duration of diabetes was 6.2 years, and the mean glycated hemoglobin value was 9.3%. Dyslipidemia was the most prevalent chronic comorbid condition (84.3%) accompanying diabetes and erectile dysfunction, followed by hypertension (56.5%). An approximately similar rate of hypogonadism was observed in patients with diabetes and erectile dysfunction regardless of whether the other chronic disease was also present. From 115 patients included in this study, hypogonadism was diagnosed in 26% of patients with diabetes and erectile dysfunction.

Conclusion A significant number of hypogonadisms occur in patients with diabetes and erectile dysfunction, which require particular emphasis.
Noise Exposure and Hearing Loss among Workers at a Hammer Forge Company
Authors: Brueck Scott E. , Eisenberg Judith , Zechmann Edward L. , Murphy William J. , Krieg Edward , Morata Thais C.
Published: June 2023

The National Institute for Occupational Safety and Health (NIOSH) evaluated continuous and impact noise exposures and hearing loss among workers at a hammer forge company. Full-shift personal noise exposure measurements were collected on forge workers across 15 different job titles; impact noise characteristics and one-third octave band noise levels were assessed at the forge hammers; and 4,750 historic audiometric test records for 483 workers were evaluated for hearing loss trends. Nearly all workers' noise exposures exceeded regulatory and/or recommended exposure limits. Workers working in jobs at or near the hammers had full-shift time-weighted average noise exposures above 100 decibels, A-weighted. Impact noise at the hammers reached up to 148 decibels. Analysis of audiometric test records showed that 82% of workers had experienced a significant threshold shift, as defined by NIOSH, and 63% had experienced a standard threshold shift, as defined by the Occupational Safety and Health Administration (OSHA). All workers with an OSHA standard threshold shift had a preceding NIOSH significant threshold shift which occurred, on average, about 7 years prior. This evaluation highlights forge workers' exposures to high levels of noise, including impact noise, and how their hearing worsened with age and length of employment.
Quality of Life and Expressed Emotion in Caregivers of Patients with Psychiatric Disorders
Authors: MTP Sabeena , EJ Agnes , Rodrigues Lavina
Published: June 2023

Background Caregivers form an integral part of the psychosocial management of patients with psychiatric conditions. Caregivers of patients with major psychiatric disorders feel burdened, as these disorders are unpredictable and long lasting. The study was aimed to assess the quality of life (QOL) and expressed emotion among caregivers of patient's with psychiatric disorders.

Materials and Methods A cross-sectional descriptive design was adopted for the study. The sample consisted of 300 caregivers of psychiatric patients who visited psychiatric outpatient department and inpatient department of selected hospital. The caregivers were selected by using convenient sampling technique. Baseline proforma, the World Health Organization Quality of Life Scale (WHO QOL BREF), and Family Attitude Scale were used to collect the data.

Results Descriptive and inferential statistics were used to analyze the data. The analysis revealed that there was a weak negative correlation between QOL and expressed emotions. The obtained “r” value (−0.14) was statistically not significant at 0.05 level of significance. Hence, the research hypothesis was rejected and the null hypothesis was accepted.

Conclusion The study concluded that there was a low negative correlation between QOL and expressed emotions. The obtained “r” value (−0.14) is statistically not significant at 0.05 level of significance. But there was association between QOL and income and occupation of the caregiver.
Life-Threatening Intracerebral Hemorrhage in Adult with ITP: Challenging Entity
Authors: Diyora Batuk , Purandare Anup , Devani Kavin , Kale Pramod , Shah Vikrant , Patankar Roy
Published: June 2023

Intracerebral hemorrhage (ICH) is a rare and fatal complication of immune thrombocytopenia. ICH is more common in children than in the adult population. A 30-year-old male patient, a known case of immune thrombocytopenia, presented with sudden onset severe headache and vomiting. Computed tomography scan showed a large right frontal intracerebral hematoma. His platelet counts were low, and he received multiple transfusions. Though he was initially conscious, his neurological condition progressively deteriorated, so the decision was taken for an emergency craniotomy. Despite multiple transfusions, his platelet counts were 10,000/µL, so craniotomy was very risky. He underwent an emergency splenectomy and received one unit of single donor platelets. Subsequently, his platelets count increased a few hours after, and he underwent successful evacuation of intracerebral hematoma. He eventually had an excellent neurological outcome. Though intracranial hemorrhage carries significant morbidity and mortality, a timely decision of emergency splenectomy followed by craniotomy can result in an excellent clinical outcome.
Adult Brainstem Astroblastoma: Unusual Presentation of a Rare Tumor
Authors: Bishnoi Ishu , Midha Rahul , Singh Karandeep , Garg Swapnil , Jain Payal
Published: June 2023

Astroblastoma is a rare tumor, which is mostly found in pediatric population. Due to scarcity of literature, the data about treatment is lacking. We are reporting case of brainstem astroblastoma in an adult female. A 45-year-old lady presented with complaint of headache, vertigo, vomiting, and nasal regurgitation for 3 months. On examination, she had weak gag, left hemiparesis. Magnetic resonance imaging brain reported medulla oblongata mass, dorsally exophytic. She underwent suboccipital craniotomy and decompression of mass. Histopathology confirmed diagnosis of astroblastoma. She underwent radiotherapy and recovered well. Brainstem astroblastoma is an extremely rare entity. The surgical resection is possible due to well-defined plane. For best outcome, maximum resection and radiation are indicated.
Idiopathic De Novo Arteriovenous Malformation: A Rare Acquired Intracranial Lesion
Authors: Plute Tritan , Agarwal Prateek , Patel Aneek , Mallela Arka N. , Lunsford L Dade , Abou-Al-Shaar Hussam
Published: June 2023

The de novo development of cerebral arteriovenous malformations (AVMs) in adults is an exceedingly rare event that has prompted the theory that a “second hit” is required to induce AVM formation. The authors document development of an occipital AVM in an adult a decade and a half after a brain magnetic resonance imaging (MRI) disclosed no abnormality. A 31-year-old male with a family history of AVMs and a 14-year history of migraines with visual auras and seizures presented to our service. Because of the onset of a first seizure and migraine headaches at age 17, the patient underwent high-resolution MRI that showed no intracranial lesion. After 14 years of progressively worsening symptoms, he underwent a repeat MRI that demonstrated a new de novo Spetzler-Martin grade 3 left occipital AVM. The patient received anticonvulsants and underwent Gamma Knife radiosurgery for his AVM. This case suggests that patients with seizures or persistent migraine headaches should have periodic repeat neuroimaging to exclude the development of a vascular cause despite an initial negative MRI.
Epidemiology and Predisposing Factors of Post-COVID Venous Thrombosis: A Concise Review
Authors: Lippi Giuseppe , Favaloro Emmanuel J.
Published: June 2023

Long-coronavirus disease 2019 (COVID-19) represents a heterogeneous clinical syndrome characterized by a pathologic continuum of signs, symptoms, and also laboratory/radiologic abnormalities that may persist for a long time after recovering from an acute severe acute respiratory syndrome-coronavirus disease 2 infection. Among the various components of this postviral condition, the risk of venous thromboembolism in patients hospitalized for COVID-19 remains considerably higher after discharge, especially in older individuals, in men, in patients with longer hospital stays and more aggressive treatment (e.g., mechanical ventilation and/or intensive care), when thromboprophylaxis is not used, and in those with a persistent prothrombotic state. Patients who have these predisposing factors should be monitored more closely to intercept any thrombosis that may occur in a post-COVID time-related manner but may also benefit from extended thromboprophylaxis and/or antiplatelet therapy.
Percutaneous Intentional Extraluminal Recanalization of Chronic Total Occlusions: A Review of Reentry Devices
Authors: Kinariwala Dhara , Taylor Amy C. , Wilkins Luke R.
Published: June 2023

Percutaneous intentional extraluminal recanalization (PIER) is an endovascular subintimal crossing technique used to treat chronic total occlusions (CTOs) of the peripheral arteries. Intraluminal revascularization remains the standard over PIER when technically feasible; however, when intraluminal approaches fail, PIER may be preferred prior to pursuit of surgical bypass grafting. The major cause of failure of PIER is inability to reenter the true lumen after crossing the CTO. Therefore, several reentry devices and endovascular techniques have been developed to allow for the operators to safely and quickly access the true lumen distal to the occlusion. Reentry devices currently available on the market include the Pioneer Plus catheter, Outback Elite catheter, OffRoad catheter, Enteer catheter, and GoBack catheter. These devices have unique methods of use and specific advantages with regard to their technical success along with reduced procedural and fluoroscopic time. In addition, there are other endovascular techniques available that may facilitate true lumen reentry and these will also be reviewed.
Surgical, Endovascular, and Multimodal Approaches to the Management of Atherosclerotic Common Femoral Artery Disease
Authors: Kugler Nathan W.
Published: June 2023

Common femoral artery disease is at the heart of nearly all treatment algorithms and decisions for patients with symptomatic peripheral arterial disease. Surgical endarterectomy has been the mainstay of common femoral treatment with a wealth of data supporting its safety, efficacy, and durability. Advances in endovascular technology and techniques for the management of iliac and superficial femoral artery disease has resulted in a paradigm shift in management. The common femoral artery has been aptly named a “no stent zone” due to anatomic and disease-specific challenges that have limited the role for endovascular techniques. New technology and techniques in the endovascular management of common femoral disease seek to change our treatment strategies. A multimodal approach utilizing a combination of angioplasty, atherectomy, and stenting has been shown most beneficial, although limited long-term data leave durability an unanswered question. While surgical treatment remains the gold standard, advances in the endovascular approach will certainly continue to improve outcomes. As truly isolated common femoral disease is a rarity, a collaborative approach combining all benefits of open and endovascular techniques in the treatment of peripheral arterial disease is essential.
Exploring MXene-based micro-supercapacitors for energy storage in wearable electronics
Authors: Thompson Avery
Published: June 2023

MXene-based energy storage exhibits excellent electrical properties under physical strain conditions.
Large single-photon detector opens door to high energy physics, dark matter, and more
Authors: Ikenson Ben
Published: June 2023

Array features large active area with single-photon sensitivity in the near-infrared and can be fabricated faster than traditional devices
Behavior of ion acoustic solitons in a two-electron temperature plasma of a multi-pole line cusp plasma device (MPD)
Authors: Shaikh Zubin , Patel A. D. , Chattopadhyay P. K. , Ghosh Joydeep , Joshi H. H. , Ramasubramanian N.
Published: June 2023

This article presents the experimental observations and characterization of ion acoustic solitons (IASs) in a unique multi-pole line cusp plasma device (MPD), in which the magnitude of the pole-cusp magnetic field can be varied. In addition, by varying the magnitude of the pole-cusp magnetic field, the proportion of the two-electron-temperature components in the filament-produced plasmas of the MPD can be varied. The solitons are experimentally characterized by measuring their amplitude-width relation and Mach numbers. The nature of the solitons is further established by making two counter-propagating solitons interact with each other. Later, the effect of the two-temperature electron population on soliton amplitude and width is studied by varying the magnitude of the pole cusp-magnetic field. It has been observed that different proportions of two-electron-temperature significantly influence the propagation of IASs. The amplitude of the solitons has been found to be inversely proportional to the effective electron temperature (Teff).
Design of a simple and low-cost solid-state ultra-fast high-voltage switch
Authors: Zhou Ziwen , Li Yifan , Liu Zhaojun , Wang Runyu , Ma Tianjie , Jia Zezhao , Yin Guangjia , Moro Ramiro , Ma Lei
Published: June 2023

Ultra-fast high-voltage switches (UFHVSs) are a core component of time-of-flight mass spectrometers for realizing high accuracy ion acceleration, deceleration, and temporal focusing. The desirable features of high performance UFHVSs include a large range of adjustability of pulse width, a high maximum output amplitude, and minute rising and falling times. Besides the simplicity of the driver circuit, the total cost of the whole device is also critical to its practical applications. In this work, we present a low-cost and easy-fabrication 5000 V bipolar solid-state UFHVS for a high-resolution mass spectrometer. A double-pulse transformer isolates the circuit’s high- and low-voltage sides and synchronously drives series-connected cascode SiC FETs to form its push–pull topology. This scheme allows transmitting drive signals with long widths but without the magnetic saturation of the transformer. Testing results show that output pulses reach a maximum voltage of 5000 V and a width of 150 µs, with rising and falling times of 8.5 and 18.3 ns, respectively. More importantly, they have nearly no voltage decay.
Comparison of nano-silver solder joints and SAC305 based on ANSYS simulation and life prediction
Authors: Yang Hui , Xu Zhengyu
Published: June 2023

With the rapid development of microelectronic interconnection technology, the reliability requirements of electronic products are becoming higher and higher. Among them, temperature has the greatest impact on electronic devices. Due to the different coefficients of thermal expansion (CTE) between the many materials of a chip, the inside of a solder joint is subjected to cyclic temperature action. Under the effect of cyclic temperature, the solder joints are subject to internal fracture resulting in the failure of the solder joint. Therefore, it is necessary to find a more reliable material for the solder joint. In this paper, the advantages and disadvantages of pure silver material and low silver material are compared by finite element simulation analysis of nano-silver pure silver material and SAC305 low silver material, and the fatigue life prediction of nano-silveris predicted by a life prediction model. Then, using the Electric Power Research Institute estimation method to estimate the fatigue life of solder joints, the results are compared with those calculated by the finite element method.
Fractional study of radiative Brinkman-type nanofluid flow across a vertical plate with the effect of Lorentz force and Newtonian heating
Authors: Allehiany F. M. , Alqahtani Aisha M. , Bilal Muhammad , Ali Aatif , Eldin Sayed M.
Published: June 2023

Contaminant removal from water is accomplished using a variety of technologies, with adsorption being the simplest, successful, cost-effective, and long-term solution. Nanocomposites made from clay minerals and polymers have developed as a new method for cleaning contaminated water in recent years. Therefore, in this paper, clay-based water nanoliquid has been analyzed across a vertical sheet. For flow analysis, Brinkman-type fluid model has been considered along with the consequences of first-order chemical reaction and heat generation/heat absorption. Conditions for Slippage velocity and Newtonian heating also have been taken into account. Using relative constitutive equations, a mathematical model for the flow analysis has been formulated in terms of coupled partial differential equations and then generalized by using constant proportional caputo fractional derivative. The fractional Laplace transform approach was used to solve the problem for exact analytical solutions. The physics of several essential flow constraints vs velocity, thermal energy, and concentration propagation have been addressed graphically using the exact solutions. To check the validity and correctness, the obtained solution is evaluated with the published work. It is worth mentioning that the heat transition rate in the fluid increases by 8.7671% by the accumulation of clay nanoparticulates, while the rate of mass transmission increases by 11.830%.
Numerical simulation of the argon dielectric barrier discharge driven by dual frequency at atmospheric pressure
Authors: Qi Bing , Tian Xiao , Zhang Tao , Wang Jing , Wang Yishan , Si Jinhai , Tang Jie
Published: June 2023

Argon dielectric barrier discharge driven by the dual frequency at atmospheric pressure has been investigated by a 1D fluid model. Temporal evolutions of voltage and charge density on dielectric surface, fluxes of electrons and ions on the surface, the spatiotemporal distribution of electron generation rate, and the spatial distribution of electron density are studied with various low-frequency (LF) voltages. Minimum sustained discharge amplitude of high frequency (HF) voltage and spatiotemporal mean electron density over one LF period varying with sheath voltage (α → γ) are also discussed. Results show that in α mode, the electron flux on the dielectric surface decreases significantly when the LF voltage amplitude is lower while the ion flux is less affected. The positive charge density on the surface increases, causing the surface voltage waveform to shift upward. When the LF voltage amplitude is 40 V and that of HF voltage is 87 V, the positive and negative values of voltage amplitude of dielectric surface are 182 and 32 V. As the LF voltage amplitude increases further, the sheath formation time is significantly delayed and the discharge terminates, and the rate of electron generation decreases significantly. The discharge is extinguished when the amplitude of LF voltage is 68 V while it regains when the amplitude reaches up to 750 V. In γ mode, when the amplitude of HF voltage reaches or exceeds its minimum sustained discharge value, the generation and distribution of electrons are almost unaffected by the amplitude of LF voltage.
Self-supported vortex texture in 3D curved magnets
Authors: Jalil Wesley B F , Dugato Danian A , Almeida Trevor P , Cooper David , Garcia Flávio
Published: June 2023

Magnetic textures in the self-supported nanostructure, such as vortex, are promising for magnetic hyperthermia therapy and spintronics due to their low remanent state and topological protection. These configurations emerge from energy minimization in confined systems, such as nanodisk or nanoparticles. There are many techniques used to confine these magnetic textures. However, the most robust, cheap, and reproducible is always sought. This work applies colloidal lithography to produce self-supported nanocaps with a vortex as the ground state. Firstly, we perform micromagnetic simulations to determine which diameters and thicknesses stabilize the vortex as a ground state on nanocaps. Secondly, we simulate the magnetization curves to find the conditions with the smallest remanent state and largest loop hysteresis curves area. Finally, we experimentally corroborate the vortex configuration ground state using electron holography and vibrating the sample magnetometer. In addition, we performed a dynamic simulation to investigate the gyrotropic modes of the vortex core. We present a concise route to the fabrication of scalable vortex magnetic nanocaps. Our results show that the magnetic nanocaps produced have a great potential for application in medicine, such as magnetic hyperthermia, and in spintronics, for spin-transfer torque nano-oscillators.
Multi-angle 3D measurement of small workpieces using EDMS algorithm
Authors: Song Kun , Yi Huaian , Lieping Zhang , Lei Jing , Huang Jiefeng
Published: June 2023

Binocular vision can get the three-dimensional information of the objects according to two-dimensional images. However, when the background texture information of the workpiece to be measured is weak, or the depth information cannot be recognized due to the change of viewing angle, it will lead to poor three-dimensional measurement accuracy. To address this problem, the paper proposes a multi-view workpiece 3D measurement method based on binocular vision. First, an experimental bench with a Chessboard is designed. The corner point reconstruction is realized by extracting the corner point of the calibration plate. The checkerboard plane is fitted by the least squares method to obtain the checkerboard plane mathematical model. Then, the vertices of the workpiece are extracted at the subpixel level, and a minimum distance sparse vertex stereo matching algorithm (EDMS) based on Euclidean distance metric is proposed to achieve accurate and fast corner matching. Finally, the three-dimensional dimensions of the workpiece are calculated. Through experiments on multiple angles of the two workpieces, the results show that the average absolute error measured by the method at different angles is 0.33 mm, the total relative error is 0.90%, and the variance is less than that 0.01 mm2, realizing the more accurate measurement of multi-view three-dimensional dimensions of small workpieces. This paper provides a new binocular vision handheld mobile 3D measurement equipment method.
A RUL prediction of bearing using fusion network through feature cross weighting
Authors: Wang Zhijian , Li Yajing , Dong Lei , Li Yanfeng , Du Wenhua
Published: June 2023

Nowadays, the methods of remaining useful life (RUL) prediction based on deep learning only use single model, or a simple superposition of two models, which makes it difficult for to maintain good generalization performance in various prediction scenarios, and ignores the dynamic sensitivity of features in the prediction, limiting the accuracy. This paper proposes a method of RUL prediction of bearing using fusion network through two-feature cross weighting (FNT-F). First, a fusion network with two subnets is proposed in this paper to adapt to the prediction problem in different scenarios. Meanwhile, a method of cross weighted joint analysis of the two features is proposed to make up for the shortcomings of feature analysis and achieve complementarity between time-domain and time–frequency features.
Determine g using Lato Lato
Authors: Wibowo Edy
Published: June 2023

We demonstrated the measurement of the Earth’s gravitational acceleration (

g

) by using Lato Lato, a popular children’s toy in Indonesia right now. We compared the obtained results with the value of the measured gravitational acceleration using a simple pendulum. The smart phone was used to record the videos of the experiment, and then we analysed the video to obtain the deviation angle (ϑ) and duration of the pendulum movement (t) of Lato Lato to determine

g

. The value obtained from the measurement using Lato Lato is

(
9.776
±
0.007

) m s−2, while

9.774
±
0.048

m s−2 is obtained by using a simple pendulum. It shows that the accuracy levels of the two techniques are comparable. Therefore, Lato Lato can be used as a simple and low-cost experimental tool for measuring the acceleration due to gravity. It is supposed to become an addition to methods that are commonly used, such as a simple pendulum and a physical pendulum.
Piezoelectric small scale generator: towards near-Joule output energy generation
Authors: Sebald Gael , Tung Nguyen Thanh , Taxil Gaspard , Ducharne Benjamin , Chavez Jhordan , Ono Takahito , Kuwano Hiroki , Lefeuvre Elie , Lallart Mickaël
Published: June 2023

Research on piezoelectric microgenerators harvesting energy from vibrations led to an abundant literature, with various strategies to optimize the frequency range and output power. In contrast, for very low frequency range (<10 Hz) and/or for non-harmonic mechanical source, the large majority of the strategies are not adapted. This work deals with a small scale piezoelectric generator where the input mechanical source consists of a single force application in the range of hundreds of Newtons (i.e. typical human weight). Contrary to harmonic mechanical sources, such an application context necessitates harvesting as much as energy as possible in a single cycle. This was achieved by assembling several piezoelectric stacks within a mechanical amplification system, and to use the electric field and stress levels close to the limits of the piezoelectric elements. Ericsson cycle (i.e. thermodynamic cycle comprising two iso-electric field and two iso-stress steps) was applied to the piezoelectric material and later two device prototypes were developed in order to quantify the harvesting capabilities. Finally, in a realistic application point of view, a passive electrical interface based on Bennet’s doubler was implemented and compared to the Ericsson cycles in terms of output energy. This electrical energy management strategy successfully allowed working at ultra-high electric field (>2 kV mm−1) enabling a converted energy density close to the ultimate value. An maximal energy density of 320 mJ cm−3 was reached using Ericsson cycles, and 130 mJ cm−3 using Bennet’s doubler (∼40% of the ultimate energy density). The device comprising ∼2.4 cm3 of piezoelectric material, the net output energy converted and stored per cycle reached 320 mJ. Still, the work presented here can be adapted to other range of forces and displacements for maximizing energy harvesting.
Ho-Mn co-doping in barium titanate piezoceramics via sol-gel process followed by microwave and conventional heating
Authors: Akbari M , Heidaryan A , Shokrollahi H , Mirzaee O
Published: June 2023

Co-doped barium titanate (BT) piezoceramics are applied in advanced energy harvesting systems. In the present study, Ba1−2xHo2xTi1−xMnxO3 (x = 0, 0.02, 0.04, and 0.06) were produced via the sol-gel-assisted solid state co-doping technique followed by microwave and conventional heating. In the current investigation, the synthesizing and phase characterization, allotropic transition, morphological examination, elemental analysis and dielectric-piezoelectric responses were investigated by x-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Thermo-Gravimetric Analysis (TGA), Field-Emission Sanning Electron Microscope (FESEM), Energy-Dispersive x-ray Spectroscopy (EDS), Mapping analysis and inductance-Capacitance-Resistance meter (LCR meter) techniques, respectively. The XRD pattern and DSC/ TGA outcomes demonstrated that tetragonal BT phases without minor BaCO3 secondary phases are synthesized properly, and that the negligible unsolicited BaCO3 phases are thoroughly calcined by a microwave at 900 °C. Doping resulted in an increase in tetragonality (c/a) of 0.19%, 0.15%, and 0.04%, respectively, compared to the pure calcined BT. Additionally, the crystallite size of BT decreased significantly by 59%, 58%, and 52%, respectively. The results revealed that the microwave-sintered samples have higher purity, drastic delicate and finer grain size distribution, and superior tetragonality with respect to the conventionally sintered furnace samples. Furthermore, the piezoelectric constant for the microwave sintered and the conventionally sintered samples with the same value of x = 0.04 were 390 and 370 (pC/N), respectively, which established that the sintering method has satisfactory affection (approximately 6%) on the piezo function of the samples. Eventually, the prepared samples which had 0, 2, 4, and 6% moles of Ho3+-Mn2+ cations and were sintered by a microwave compared to the similar specimens fabricated by the furnace had superior dielectric constants of 2.6, 1.1, 2.2 and 2.9 times, respectively.
The Von Neumann conditions for the upwind and Lax-Wendroff schemes of the Telegraph Equation
Authors: Ren Jiaojiao , Wu Cong
Published: June 2023

In this paper, the Von Neumann conditions for the Upwind and Lax-Wendroff schemes of the Telegraph Equation are derived, but then prove to be contradicted with the proportional relation between time and space steps, determined by voltage and current waves’ propagation velocity. The contradiction implies that the stable Upwind and Lax-Wendroff schemes of the Telegraph Equation are not physically applicable.
Foreground separation and constraints on primordial gravitational waves with the PICO space mission
Authors: Aurlien Ragnhild , Remazeilles Mathieu , Belkner Sebastian , Carron Julien , Delabrouille Jacques , Eriksen Hans Kristian , Flauger Raphael , Fuskeland Unni , Galloway Mathew , Górski Krzysztof M. , Hanany Shaul , Hensley Brandon S. , Colin Hill J. , Lawrence Charles R. , Pryke Clement , van Engelen Alexander , Wehus Ingunn Kathrine
Published: June 2023

PICO is a concept for a NASA probe-scale mission aiming to detect or constrain the tensor to scalar ratio r, a parameter that quantifies the amplitude of inflationary gravity waves.
We carry out map-based component separation on simulations with five foreground models and input r values r
in = 0 and r
in = 0.003. We forecast r determinations using a Gaussian likelihood assuming either no delensing or a residual lensing factor A
lens = 27%. By implementing the first full-sky, post component-separation, map-domain delensing, we show that PICO should be able to achieve A
lens = 22% – 24%. For four of the five foreground models we find that PICO would be able to set the constraints r < 1.3 × 10-4 to r < 2.7 × 10-4 (95%) if r
in = 0, the strongest constraints of any foreseeable instrument. For these models, r = 0.003 is recovered with confidence levels between 18σ and 27σ. We find weaker, and in some cases significantly biased, upper limits when removing few low or high frequency bands. The fifth model gives a 3σ detection when r
in = 0 and a 3σ bias with r
in = 0.003. However, by correlating r determinations from many small 2.5% sky areas with the mission's 555 GHz data we identify and mitigate the bias. This analysis underscores the importance of large sky coverage. We show that when only low multipoles ℓ ≤ 12 are used, the non-Gaussian shape of the true likelihood gives uncertainties that are on average 30% larger than a Gaussian approximation.
The CMB cold spot under the lens: ruling out a supervoid interpretation
Authors: Owusu Stephen , da Silveira Ferreira Pedro , Notari Alessio , Quartin Miguel
Published: June 2023

The Cosmic Microwave Background (CMB) anisotropies are thought to be statistically
isotropic and Gaussian. However, several anomalies are observed, including the CMB Cold Spot, an
unexpected cold ∼ 10° region with p-value ≲ 0.01 in standard
ΛCDM. One of the proposed origins of the Cold Spot is an unusually large void on the line
of sight, that would generate a cold region through the combination of integrated Sachs-Wolfe and
Rees-Sciama effects. In the past decade extensive searches were conducted in large scale
structure surveys, both in optical and infrared, in the same area for z ≲ 1 and did find
evidence of large voids, but of depth and size able to account for only a fraction of the
anomaly. Here we analyze the lensing signal in the Planck CMB data and rule out the hypothesis
that the Cold Spot could be due to a large void located anywhere between us and the surface of
last scattering. In particular, computing the evidence ratio we find that a model with a large
void is disfavored compared to ΛCDM, with odds 1 : 13 (1 : 20) for SMICA (NILC) maps,
compared to the original odds 56 : 1 (21 : 1) using temperature data alone.
Study of discharges in the CMS GEM GE1/1 station with LHC beam
Authors: Calzaferri S.
Published: June 2023

The Large Hadron Collider (LHC) and the experiments installed there are being upgraded for
the High Luminosity LHC project that will provide a greatly enlarged data sample in the search for
physics beyond the Standard Model. During Long Shutdown 2, from 2018 to the first months of 2022,
some of these upgrades were completed. In particular, the muon spectrometer of the CMS experiment
was upgraded with installation of the GE1/1 detector station, based on Gas Electron Multiplier
(GEM) technology. This station is positioned in the endcap region of the CMS muon system and
covers the pseudorapidity range 1.55 < |η| < 2.18. On the 5th of July, 2022, Run 3 of
the LHC began with collision energy of 13.6 TeV. The newly installed GEM detectors experienced
high-voltage discharges when the beams were colliding inside CMS. To monitor these events and to
understand how to safely operate the detectors, a study of these phenomena became necessary. The
intensity of discharge current and the discharge rate were recorded in different detectors as a
function of luminosity and time. It was observed that some chambers have a significantly higher
discharge rate than the modal value of rate over the entire chamber population. The reasons
responsible for this behavior are currently under investigation. In this contribution, an analysis
of discharges will be presented, illustrating the dependence of discharge rate on different LHC
beam configurations and the high voltage working point of the chambers.
Novel resistive charge-multipliers for dual-phase LAr-TPCs: towards stable operation at higher gains
Authors: Tesi A. , Moleri L. , Leardini S. , Breskin A. , Gonzalez-Diaz D. , Olano-Vegas L. , Jash A. , Bressler S.
Published: June 2023

Cryogenic versions of Resistive WELL (RWELL) and Resistive Plate WELL (RPWELL) detectors
have been developed, aimed at stable avalanche multiplication of ionization electrons in the vapor
phase of LAr (dual-phase TPC). In the RWELL, a thin resistive DLC layer deposited on top of an
insulator is inserted in between the electron multiplier (THGEM) and the readout anode; in the
RPWELL, a resistive ferrite plate is directly coupled to the THGEM. Radiation-induced ionization
electrons in the liquid are extracted into the gaseous phase. They drift into the THGEM's holes
where they undergo charge multiplication. Embedding resistive materials into the multiplier proved
to enhance operation stability due to the mitigation of electrical discharges — thus allowing
operation at higher charge gain compared to standard THGEM (a.k.a. LEM) multipliers. We present
the detector concepts and report on the main preliminary results.
Assessing nitrogen flow and nitrogen footprint in the food system of a subtropical island with a scenario to mitigate nitrogen load impacted by trade-dependent agriculture
Authors: Hamada Kosuke , Eguchi Sadao , Hirano Nanae , Asada Kei , Oka Naoko
Published: June 2023

Recent hikes in fertilizer, feed, and food prices threaten the food security of island-dwelling people who rely heavily on imports to sustain food supply and production. The influx of reactive nitrogen (Nr) through imports increases nitrogen load and degrades the environment. To overcome these problems, a robust and sustainable food system must be developed. In this study, we aimed to evaluate the present nitrogen flow in the food system of Ishigaki Island, located in the subtropical zone of Japan, and propose a measure to improve it based on the nitrogen footprint concept. Results showed that the major Nr-loss pathways for agricultural activity on the island were ‘crop-unused’ (37%) and ‘manure’ (43%). In food production, most of the Nr loss to the environment was related to export products, and less than 30% was related to island consumers. To meet the demand of food supply on the island, 5.1 times greater amount of food Nr than that of produced for island consumers was imported from overseas regions, placing the burden of Nr loss on such regions. We found that agricultural activities on the island mainly used chemical fertilizer; less than 13% of cattle manure was reused. To reduce the influx of Nr, we created a scenario in which 30% of chemical fertilizer was replaced by cattle manure. Results indicated 70% of the cattle manure produced on the island was necessary to achieve this scenario. This system could reduce Nr imports and Nr loss on the island by 16% and 17%, respectively. The proposed food system can be extended to other islands to overcome the recent price hikes and conserve the environment. This study is the first to present a detailed nitrogen flow in the food system of a tropical/subtropical island by using the nitrogen footprint concept.
Numerical modelling of reinforced concrete gravity retaining walls under seismic loads
Authors: Yamouni B El , Khannoussi F El , Khamlichi A
Published: June 2023

Due to their multiple uses and structural challenges they outline during normal circumstances and seismic events, retaining walls constitute an important concern for civil engineers. Design of these structures requires accurate determination of lateral earth pressure under various conditions. Considering the dynamical action under seismic excitation, the total lateral earth pressure for cohesion-less soil backfills is often estimated by using the Mononobe-Okabe method. Although this conventional method does not take into account the full characteristics of a seism, it has recovered a wide range of applications in practice. It is interesting therefore to compare its predictions to those of a more comprehensive analysis. In this study, a dynamic numerical modelling of reinforced concrete gravity retaining walls with cohesion-less backfill material was conducted using PLAXIS 2D software. Loma Prieta earthquake record was applied and different values of wall height and backfill soil stiffness were considered. Parametric studies were accomplished in order to assess the influence of key parameters on the vertical profile of dynamic active earth pressure and the resultant thrust. A good agreement between the numerically computed seismic lateral force acting on the wall was obtained in comparison with the conventional Mononobe-Okabe approach; however this last may yield oversizing.
Development of geometry variants and forming technology for metal diaphragms to increase the efficiency of diaphragm compressor
Authors: Solovev M , Leonhardt A , Graf A , Kunke A , Kräusel V
Published: June 2023

This article outlines the development of an elastically foldable, bistable diaphragm geometry that enables an increase in the compression volume of diaphragm compressors compared to the use of flat diaphragms. Using a Finite Element Model (FEM) in ABAQUS/Standard, several membrane geometries (truncated cone, cone, and dome) were calculated and analyzed with regard to their elastic deformation. Selected geometries were produced using Single Point Incremental Forming (SPIF) and tested by applying full-area pneumatic pressure to determine the diaphragm’s lifetime.