Reducing Conversion Time of the Iterative-Integrating Measuring Converter

Because of its high resolution, low cost, small volume, low power dissipation and less conversion time consumption, the direct digital synthesizer (DDS) method has been applied more and more in the fields of frequency synthesis and signal generation. However, only a limited number of precise frequency signals can be synthesized by the traditional DDS, for the reason that its accumulator modulus is fixed, and its frequency tuning word must be integer. In this paper, a precise DDS method using compound frequency tuning word is proposed, which improves the accuracy of synthesized signals at any frequency points on the premise of guaranteeing the stability of synthesized signals. In order to verify the effectiveness of the new method, a DDS frequency synthesizer based on FPGA is designed and implemented. Taking the rubidium atomic clock PRS10 as standard frequency source, the experiments shows that the frequency stability of the synthesized signal is better than 8.0 × 10−12/s, the relative frequency error is less than 4.8 × 10−12, and that the frequency accuracy is improved by three orders of magnitude compared with the traditional DDS method.

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An AD Conversion Based on the Interpolation Parallel Series Circuit

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1049-1050.568 ◽

2014 ◽

Vol 1049-1050 ◽

pp. 568-572

Author(s):

Ju Fang Hu

Keyword(s):

High Resolution ◽

Circuit Design ◽

High Price ◽

Electronic Technology ◽

Conversion Time ◽

Working Mechanisms ◽

Parallel Series

s. The electronic technology is a key component of digital high-resolution ADC converter. Currently based on comparative parallel ADC conversion time up to nanoseconds, and even nanosecond commercialization devices are also listed a large number with high price. This paper introduces an AD conversion based on the interpolation parallel series circuit. The working mechanisms are reported and the key circuit design is illustrated in details. The experiments are carried out in this paper for examining the circuit. The results show the good performance.

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Not Only High Number and Specific Comorbidities but Also Age Are Closely Related to Progression and Poor Prognosis in Patients With COVID-19

Frontiers in Medicine ◽

10.3389/fmed.2021.736109 ◽

2022 ◽

Vol 8 ◽

Author(s):

Dafeng Liu ◽

Yongli Zheng ◽

Jun Kang ◽

Dongmei Wang ◽

Lang Bai ◽

...

Keyword(s):

Clinical Trial ◽

Disease Progression ◽

Disease Severity ◽

Poor Prognosis ◽

Chronic Obstructive ◽

Clinical Trial Registry ◽

Alcoholic Fatty Liver ◽

Clinical Type ◽

Conversion Time ◽

Negative Conversion

Background: Some patients with comorbidities and rapid disease progression have a poor prognosis.Aim: We aimed to investigate the characteristics of comorbidities and their relationship with disease progression and outcomes of COVID-19 patients.Methods: A total of 718 COVID-19 patients were divided into five clinical type groups and eight age-interval groups. The characteristics of comorbidities were compared between the different clinical type groups and between the different age-interval groups, and their relationships with disease progression and outcomes of COVID-19 patients were assessed.Results: Approximately 91.23% (655/718) of COVID-19 patients were younger than 60 years old. Approximately 64.76% (465/718) had one or more comorbidities, and common comorbidities included non-alcoholic fatty liver disease (NAFLD), hyperlipidaemia, hypertension, diabetes mellitus (DM), chronic hepatitis B (CHB), hyperuricaemia, and gout. COVID-19 patients with comorbidities were older, especially those with chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD). Hypertension, DM, COPD, chronic kidney disease (CKD) and CVD were mainly found in severe COVID-19 patients. According to spearman correlation analysis the number of comorbidities was correlated positively with disease severity, the number of comorbidities and NAFLD were correlated positively with virus negative conversion time, hypertension, CKD and CVD were primarily associated with those who died, and the above-mentioned correlation existed independently of age. Risk factors included age, the number of comorbidities and hyperlipidaemia for disease severity, the number of comorbidities, hyperlipidaemia, NAFLD and COPD for the virus negative conversion time, and the number of comorbidities and CKD for prognosis. Number of comorbidities and age played a predictive role in disease progression and outcomes.Conclusion: Not only high number and specific comorbidities but also age are closely related to progression and poor prognosis in patients with COVID-19. These findings provide a reference for clinicians to focus on not only the number and specific comorbidities but also age in COVID-19 patients to predict disease progression and prognosis.Clinical Trial Registry: Chinese Clinical Trial Register ChiCTR2000034563.

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Factors Influencing Sputum Smear and Culture Conversion Time among Patients with Pulmonary Tuberculosis

Nepal Medical Journal ◽

10.37080/nmj.14 ◽

2018 ◽

Vol 1 (01) ◽

pp. 41-46

Author(s):

Pushpa Man Shrestha ◽

Minani Gurung ◽

Nabin Kumar Chaudhary

Keyword(s):

Pulmonary Tuberculosis ◽

Erythrocyte Sedimentation Rate ◽

Sedimentation Rate ◽

Smoking Habit ◽

Sputum Smear ◽

Erythrocyte Sedimentation ◽

Sputum Conversion ◽

Conversion Time ◽

Index Value ◽

Culture Conversion

Introduction: Pulmonary tuberculosis is a contagious bacterial infection that involves the lungs and it may spread to other organs. Sputum smear and culture conversion are important indicators for the effectiveness of treatment and the infectivity of the patient. The present study aims to find sputum smear and culture conversion time and the factors that influence the conversion time among tuberculosis patients at National Tuberculosis Centre in Nepal. Methods: A total of 54 patients, who were diagnosed with laboratory confirmed pulmonary tuberculosis and under antitubercular therapy were monitored for sputum smear and culture conversion time. The blood specimens from each patient were processed for hemoglobin, platelets, erythrocyte sedimentation rate and blood glucose levels. Patient’s clinical history, risk factors that prolong conversion time and sociodemographic information were also collected by direct interview. Results: The mean sputum smear and culture conversion were found to be 54.4 days and 45.5 days respectively. Old age, smoking habit, low body mass index value, Treatment category II, initial bacillary load and abnormal erythrocyte sedimentation rate values were found to be associated with long sputum conversion time. Radiographic involvement of only left lungs, presence of fewer symptoms, aged between 15-45 years, having normal weight, without smoking habit and being married, were found to be associated with short sputum conversion time. Conclusions: The sputum microscopy, old age, smoking habit, low body mass index value, treatment category II, initial bacillary load and abnormal erythrocyte sedimentation rate value had been found to be significantly associated with long sputum conversion time.

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Revised Crackling Core Model Accounting for Fragmentation Effect and Variable Grain Conversion Time : Application to UO2 Sphere Oxidation

Journal of the Nuclear Fuel Cycle and Waste Technology(JNFCWT) ◽

10.7733/jnfcwt.2018.16.4.411 ◽

2018 ◽

Vol 16 (4) ◽

pp. 411-420

Author(s):

Ju Ho Lee ◽

Yung-Zun Cho

Keyword(s):

Core Model ◽

Conversion Time

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An Extended-Counting Incremental Sigma–Delta ADC with Hardware-Reuse Technique

Journal of Circuits System and Computers ◽

10.1142/s0218126616500389 ◽

2016 ◽

Vol 25 (05) ◽

pp. 1650038

Author(s):

Xinji Zeng ◽

Jing Gao ◽

Liu Yang ◽

Jiangtao Xu

Keyword(s):

Conversion Rate ◽

Cmos Process ◽

Digital Output ◽

Sigma Delta ◽

Design And Implementation ◽

Conversion Time ◽

Cyclic Adc ◽

Sigma Delta Adc ◽

Oversampling Ratio ◽

Least Significant Bits

This paper presents the design and implementation of an extended-counting incremental sigma–delta ADC (IDC) with hardware-reuse technique. The proposed ADC architecture is a cascaded configuration of a second-order IDC and a two-stage cyclic ADC. The operation of the ADC consists of the “coarse phase” and the “fine phase”. In the “coarse phase”, the circuit works as an IDC to achieve the most significant bits (MSBs) and produce the residue voltage. Then in the “fine phase”, it is reused and changed to work as a cyclic ADC to quantize the residue voltage and achieve the least significant bits (LSBs). Eventual digital output is achieved by combining the two parts together. The utilization of extended-counting technique significantly reduces the conversion time and increases the conversion rate, and the hardware-reuse technique removes the demand for additional circuit area. The ADC is designed in 0.5[Formula: see text][Formula: see text]m CMOS process, which has a conversion rate of 43.48[Formula: see text]kS/s with oversampling ratio (OSR) of 23 and achieves 84.83[Formula: see text]dB SNDR and 13.799-bit ENOB. It consumes 2.4[Formula: see text]mW with a 5[Formula: see text]V voltage supply, and the FOM is 3.87[Formula: see text]pJ/step.

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