An Application of Minimum Statistical Noise Estimation in the High Rate of Fire Artillery Muzzle Velocity Measurement

2013 ◽  
Vol 347-350 ◽  
pp. 332-336
Author(s):  
Feng Ju ◽  
Lin Shi ◽  
Hong Wei Zhang ◽  
Zhuang Zhi Han

The infrared starter is usually used to measure the artillery’s muzzle velocity, but due to the continued firelight near the muzzle produced by the continuous occurrence of the high rate of fire artillery projectile , so that the misjudgment and the Missing are easily produced by the infrared sensor . Continuous wave radar can effectively overcome the impact of the fire, but the detection accuracy of the leaving time is greatly affected echo because of the flame noise. Therefore the noise reduction of echo signal is an important step about the detection of the leaving time. For this problem, a noise reduction algorithm based on the minimum statistical noise estimation is proposed in this paper by the analysis of the echo signal. The noise of continuous muzzle flame is effectively reduced by the algorithm. It is verified correct and feasible by the processing of the measured signal. It lays the foundation for the measure of the artillery’s muzzle velocity and the engineering realization of muzzle velocity measurement.

2017 ◽  
Vol 45 (10) ◽  
pp. 1607-1618 ◽  
Author(s):  
Seung Yun Lee ◽  
Sunho Jung ◽  
Sangdo Oh ◽  
Seong Hoon Park

We proposed that a moderator, others' similarity, would determine the impact of high participation rates of others on an individual's charitable behavior, and aimed to show that this moderator would work through the diffusion of responsibility motive. Participants (N = 152 undergraduate students) completed measures of charitable behavior and diffusion of responsibility, after being assigned to 1 of 2 conditions where a set percentage of other students (manipulated as either similar undergraduate students or dissimilar graduate students) were stated to have already donated to a charitable campaign (high contribution condition = 70% participation, low contribution condition = 30% participation). Our results showed that the high participation rate of others increased an individual's charitable behavior when the others in question were similar to that individual, but not when the others were dissimilar. In addition, the high rate of participation by others increased the diffusion of responsibility motive when the others in question were dissimilar to that individual, leading to a negative effect on that individual's charitable behavior.


2021 ◽  
Vol 22 (13) ◽  
pp. 7051
Author(s):  
Vitalii Kim ◽  
Emily Gudvangen ◽  
Oleg Kondratiev ◽  
Luis Redondo ◽  
Shu Xiao ◽  
...  

Intense pulsed electric fields (PEF) are a novel modality for the efficient and targeted ablation of tumors by electroporation. The major adverse side effects of PEF therapies are strong involuntary muscle contractions and pain. Nanosecond-range PEF (nsPEF) are less efficient at neurostimulation and can be employed to minimize such side effects. We quantified the impact of the electrode configuration, PEF strength (up to 20 kV/cm), repetition rate (up to 3 MHz), bi- and triphasic pulse shapes, and pulse duration (down to 10 ns) on eliciting compound action potentials (CAPs) in nerve fibers. The excitation thresholds for single unipolar but not bipolar stimuli followed the classic strength–duration dependence. The addition of the opposite polarity phase for nsPEF increased the excitation threshold, with symmetrical bipolar nsPEF being the least efficient. Stimulation by nsPEF bursts decreased the excitation threshold as a power function above a critical duty cycle of 0.1%. The threshold reduction was much weaker for symmetrical bipolar nsPEF. Supramaximal stimulation by high-rate nsPEF bursts elicited only a single CAP as long as the burst duration did not exceed the nerve refractory period. Such brief bursts of bipolar nsPEF could be the best choice to minimize neuromuscular stimulation in ablation therapies.


2021 ◽  
Vol 11 (11) ◽  
pp. 4722
Author(s):  
Botan Wang ◽  
Xiaolong Chen ◽  
Yi Wang ◽  
Dong Han ◽  
Baohong Guo ◽  
...  

This work reports the latest observations on the behavior of two Multigap Resistive Plate Chambers (MRPC) under wide high-luminosity exposures, which motivate the development and in-beam test of the sealed MRPC prototype assembled with low-resistive glass. The operation currently being monitored, together with previous simulation results, shows the impact of gas pollution caused by avalanches in gas gaps, and the necessity to shrink the gas-streaming volume. With the lateral edge of the detector sealed by a 3D-printed frame, a reduced gas-streaming volume of ~170 mL has been achieved for a direct gas flow to the active area. A high-rate test of the sealed MRPC prototype shows that, ensuring a 97% efficiency and 70 ps time resolution, the sealed design results in a stable operation current behavior at a counting rate of 3–5 kHz/cm2. The sealed MRPC will become a potential solution for future high luminosity applications.


Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 407
Author(s):  
Ana Luiza Bierrenbach ◽  
Yoonyoung Choi ◽  
Paula de Mendonça Batista ◽  
Fernando Brandão Serra ◽  
Cintia Irene Parellada ◽  
...  

Background: In 2014, a recommended one-dose of inactivated hepatitis A vaccine was included in the Brazilian National Immunization Program targeting children 12–24 months. This decision addressed the low to intermediate endemicity status of hepatitis A across Brazil and the high rate of infection in children and adolescents between 5 and 19 years old. The aim of the study was to conduct a time-series analysis on hepatitis A incidence across age groups and to assess the hepatitis A distribution throughout Brazilian geographic regions. Methods: An interrupted time-series analysis was performed to assess hepatitis A incidence rates before (2010–2013) and after (2015–2018) hepatitis A vaccine program implementation. The time-series analysis was stratified by age groups while a secondary analysis examined geographic distribution of hepatitis A cases. Results: Overall incidence of hepatitis A decreased from 3.19/100.000 in the pre-vaccine period to 0.87/100.000 (p = 0.022) post-vaccine introduction. Incidence rate reduction was higher among children aged 1-4 years old, with an annual reduction of 67.6% in the post-vaccination period against a 7.7% annual reduction in the pre-vaccination period (p < 0.001). Between 2015 and 2018, the vaccination program prevented 14,468 hepatitis A cases. Conclusion: Our study highlighted the positive impact of a recommended one-dose inactivated hepatitis A vaccine for 1–4-years-old in controlling hepatitis A at national level.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jonatan Almagor ◽  
Stefano Picascia

AbstractA contact-tracing strategy has been deemed necessary to contain the spread of COVID-19 following the relaxation of lockdown measures. Using an agent-based model, we explore one of the technology-based strategies proposed, a contact-tracing smartphone app. The model simulates the spread of COVID-19 in a population of agents on an urban scale. Agents are heterogeneous in their characteristics and are linked in a multi-layered network representing the social structure—including households, friendships, employment and schools. We explore the interplay of various adoption rates of the contact-tracing app, different levels of testing capacity, and behavioural factors to assess the impact on the epidemic. Results suggest that a contact tracing app can contribute substantially to reducing infection rates in the population when accompanied by a sufficient testing capacity or when the testing policy prioritises symptomatic cases. As user rate increases, prevalence of infection decreases. With that, when symptomatic cases are not prioritised for testing, a high rate of app users can generate an extensive increase in the demand for testing, which, if not met with adequate supply, may render the app counterproductive. This points to the crucial role of an efficient testing policy and the necessity to upscale testing capacity.


2021 ◽  
Vol 39 (28_suppl) ◽  
pp. 264-264
Author(s):  
Jacob Cogan ◽  
Melissa Kate Accordino ◽  
Melissa Parsons Beauchemin ◽  
Sophie Ulene ◽  
Elena B. Elkin ◽  
...  

264 Background: Opioid misuse is a public health crisis. Initial opioid exposures often occur post-operatively, and 10% of opioid-naïve patients who undergo cancer surgery subsequently become long-term opioid users. It has been shown that 70% of opioids prescribed post-operatively go unused, but only 9% of unused pills are disposed appropriately, which increases the risk of unintended use. We evaluated the impact of an inexpensive, password-protected dispensing device with mail return capacity on retrieval of unused pills after cancer surgery. Methods: Adult patients scheduled for major cancer-related surgery were eligible. Enrolled patients received opioid prescriptions in a password-protected, pill-dispensing device (Addinex) from a specialty pharmacy. The mechanical device links to a smartphone app, which provides passwords on a prescriber-defined schedule. Patients request a password when they are in pain, enter the password into the device and receive a pill if the prescribed time has elapsed. The smartphone app provides clinical guidance based on patient-reported pain levels, and suggests tapering strategies. Patients are instructed to return the device in a DEA-approved mailer when opioid use is no longer required for pain control. Unused pills are destroyed upon receipt. The primary objective was to determine the feasibility of device return, defined as > 50% of patients with device return. We also explored patterns of device use, patient reported outcomes, and device satisfaction via surveys and semi-structured interviews. Results: Between October, 2020 and April, 2021, 13 patients completed the study; 4 patients are currently enrolled. Among the initial 13 patients, 7 underwent abdominal hysterectomy, 4 underwent mastectomy and 2 underwent cutaneous tumor resections. The majority of these patients (n = 10, 77%) returned the device, and more than half (n = 7, 54%) returned the device within 6 weeks of surgery. Only a minority of patients (n = 5, 38%) used the device to obtain opioids; most (n = 8, 62%) used no opioids at home, and all of these patients returned the device and the unused pills. Of 11 patients who participated in semi-structured interviews, most (n = 7, 64%) said they felt safer having opioids in the device instead of a regular pill bottle. Among device users, the majority (n = 4, 80%) reported an overall positive experience. All non-users reported having no opioid requirement for pain control. Conclusions: Our early findings suggest that use of an inexpensive, password-protected, pill-dispensing device to assist with opioid dispensing and return is feasible, with a high rate of device and unused opioid return to the pharmacy. This strategy may be effective for reducing opioid diversion. Analyses and recruitment are ongoing to evaluate the benefits of reducing post-operative opioid consumption.


2017 ◽  
Vol 30 (7-8) ◽  
pp. 517
Author(s):  
Rodrigo Andrade ◽  
Manuel Gonçalves-Pinho ◽  
António Roma-Torres ◽  
Isabel Brandão

Introduction: Anorexia nervosa is a severe, usually chronic, life-threatening disease of complex etiology characterized by food restriction, overestimation of the importance of body weight and image, intense fear of weight gain and distortion of body image. Anorexia nervosa is associated with high rates of mortality, suicide and decreased quality of life. Our aim is to present an anorexia nervosa treatment program offered in a major university hospital in Portugal, and to determine the impact of illness duration before admission on the outcome. Our hypothesis is that patients with greater disease longevity may have worse prognosis and poorer outcome.Material and Methods: The sample included data from case records of 169 patients seen consecutively and for the first time at Centro Hospitalar São João, between 2010 and 2015. We performed a retrospective observational study which included data collected at admission and from later follow-up years.Results: From the initially selected patients, 14.8% reached total remission, 16% accomplished partial remission and 14.2% ended up with exacerbation/stagnation of the disease. The dropout rate was of 55% throughout our study period. We found significant differences on outcome rates between distinct illness duration groups (p = 0.007).Discussion: There are several factors frequently associated with poor outcome for anorexia nervosa. The interpretation of outcome findings was limited by the high rate of dropout and lack of consistent definition criteria.Conclusion: Our results support the idea that illness duration has an important role on the outcome and prognostic features of these patients.


2007 ◽  
Vol 8 (4) ◽  
pp. 268-274 ◽  
Author(s):  
M.C. Beaulieu ◽  
C. Gabana ◽  
C. Rose ◽  
P.S. Macdonald ◽  
J. Clement ◽  
...  

Background With an increased focus on native AV fistula creation in hemodialysis patients, a transposed brachiobasilic fistula (tBBF) is becoming an increasingly utilized option. This study describes the outcomes of tBBFs in a chronic hemodialysis population. In particular, we focus on the incidence and location of stenosis, and review the impact of angioplasty on these lesions. Methods A retrospective cohort study using all patients with a tBBF created between January 2001 and December 2004. Results Of the 543 fistulas created during the study period, 93 were tBBFs. The mean age of patients was 65 years, 56% were male and 55% were diabetic. Stenosis occurred in 54% (46/85) of fistulas; the location of stenosis in the majority (74%) was at or near the area of basilic vein transposition and 50% of fistulas with stenosis in this location required three or more angioplasties. Primary (unassisted) patency was 42% at one year in this cohort. Secondary patency was 68% at 1 year and 58% and 53% at 2 and 3 years respectively. Conclusion In a cohort of hemodialysis patients who received a tBBF, we describe a reasonable primary and secondary patency rate and a high rate of stenosis at the point of transposition of the basilic vein. Such stenosis usually requires multiple percutaneous or surgical interventions to ensure or reestablish conduit patency. Further study is required regarding the optimal surgical technique, monitoring, and treatment of stenosis of this fistula type including the utility of repeat angioplasty.


2021 ◽  
Author(s):  
Astha Thakkar ◽  
Jesus Gonzalez Lugo ◽  
Niyati Goradia ◽  
Radhika Gali ◽  
Lauren C. Shapiro ◽  
...  

As COVID-19 has been shown to adversely affect patients with cancer, prophylactic strategies are critically needed. We determined the immunogenicity of COVID-19 vaccination in a cohort of cancer patients that had received full dosing with one of the FDA-approved COVID-19 vaccines. 201 oncology patients underwent anti-spike protein SARS-CoV-2 IgG testing post-vaccination and demonstrated a high rate of seroconversion (94%) overall. When compared to solid tumors (98%), a significantly lower rate of seroconversion was observed in patients with hematological malignancies (85%), particularly recipients of anti-CD20 therapies (70%) and stem cell transplantation (74%). Patients receiving immune checkpoint inhibitor therapy (97%) or hormonal therapies (100%) demonstrated high seroconversion post-vaccination. Patients with prior COVID-19 infection demonstrated higher anti-spike IgG titers post-vaccination. Relatively lower IgG titers were noted following vaccination with the adenoviral when compared to the mRNA-based vaccines. These data demonstrate generally high immunogenicity of COVID-19 vaccination in oncology patients and identify vulnerable cohorts that need novel vaccination or passive immunization strategies.


2020 ◽  
Author(s):  
Johanna Stéen ◽  
Jesper Tranekjær Jørgensen ◽  
Denk Christoph ◽  
Umberto Maria Battisti ◽  
Kamilla Nørregaard ◽  
...  

<p>The development of highly selective and fast biocompatible reactions for ligation and cleavage has paved the way for new diagnostic and therapeutic applications of <i>in vivo</i> chemistry. The concept of bioorthogonal pretargeting has attracted considerable interest, in particular for the targeted delivery of radionuclides and drugs. In nuclear medicine, pretargeting can provide increased target-to-background ratios at early time-points compared to traditional approaches. This reduces the radiation burden to healthy tissue and, depending on the selected radionuclide, enables better imaging contrast or higher therapeutic efficiency. Moreover, bioorthogonally triggered cleavage of pretargeted antibody-drug conjugates represents an emerging strategy to achieve controlled release and locally increased drug concentrations. The toolbox of bioorthogonal reactions has significantly expanded in the past decade, with the tetrazine ligation being the fastest and one of the most versatile <i>in vivo</i> chemistries. Progress in the field, however, relies heavily on the development and evaluation of (radio)labeled compounds, preventing the use of compound libraries for systematic studies. The rational design of tetrazine probes and triggers has thus been impeded by the limited understanding of the impact of structural parameters on the <i>in vivo</i> ligation performance. In this work, we describe the development of a pretargeted blocking assay that allows for the investigation of the <i>in vivo</i> fate of a structurally diverse library of 45 unlabeled tetrazines and their capability to reach and react with pretargeted <i>trans</i>-cyclooctene (TCO)-tagged antibodies in tumor-bearing mice. This study enabled us to assess the correlation of click reactivity and lipophilicity of tetrazines with their <i>in vivo</i> performance. In particular, high rate constants (>50,000 M<sup>-1</sup>s<sup>-1</sup>) for the reaction with TCO and low calculated log<i>D</i><sub>7.4</sub> values (below -3) of the tetrazine were identified as strong indicators for successful pretargeted <i>in vivo</i> click chemistry. Click-radiolabeling gave access to a set of selected <sup>18</sup>F-labeled tetrazines, including highly reactive scaffolds, which were used in pretargeted PET imaging studies to confirm the results from the blocking study. These insights thus enable the rational design of tetrazine probes for <i>in vivo</i> application and will thereby assist the clinical translation of bioorthogonal pretargeting.</p>


Sign in / Sign up

Export Citation Format

Share Document