Minimizing the Standard Deviation of Spatially Averaged Surface Cross-Sectional Data From the Dual-Frequency Precipitation Radar

2017 ◽  
Vol 55 (3) ◽  
pp. 1709-1716 ◽  
Author(s):  
Robert Meneghini ◽  
Hyokyung Kim
Keyword(s):  
Standard Deviation ◽  
Dual Frequency ◽  
Precipitation Radar ◽  
Cross Sectional

Error Analysis and Modeling of GPM Dual-Frequency Precipitation Radar Near-surface Rainfall Product

2021 ◽  
Keyword(s):  
Standard Deviation ◽  
Systematic Error ◽  
Random Error ◽  
Convective Precipitation ◽  
Dual Frequency ◽  
Precipitation Radar ◽  
Near Surface ◽  
Surface Rainfall ◽  
Comparison Results ◽  
Stratiform Precipitation

Abstract The error characterization of rainfall products of spaceborne radar is essential for better applications of radar data, such as multi-source precipitation data fusion and hydrological modeling. In this study, we analyzed the error of the near-surface rainfall product of the dual-frequency precipitation radar (DPR) on the Global Precipitation Measurement Mission (GPM) and modeled it based on ground C-band dual-polarization radar (CDP) data with optimization rainfall retrieval. The comparison results show that the near-surface rainfall data were overestimated by light rain and slightly underestimated by heavy rain. The error of near-surface rainfall of the DPR was modeled as an additive model according to the comparison results. The systematic error of near-surface rainfall was in the form of a quadratic polynomial, while the systematic error of stratiform precipitation was smaller than that of convective precipitation. The random error was modeled as a Gaussian distribution centered at −1−0 mm h−1. The standard deviation of the Gaussian distribution of convective precipitation was 1.71 mm h−1 and the standard deviation of stratiform precipitation was 1.18 mm h−1, which is smaller than that of convective precipitation. In view of the precipitation retrieval algorithm of DPR, the error causes were analyzed from the reflectivity factor (Z) and the drop size distribution (DSD) parameters (Dm, Nw). The high accuracy of the reflectivity factor measurement results in a small systematic error. Importantly, the negative bias of Nw was very obvious when the rain type was convective precipitation, resulting in a large random error.

Internet Addiction Status and Related Factors among Medical Students: A Cross-Sectional Study in Western Iran

2021 ◽  
pp. 0272684X2110254
Author(s):  
Habibolah Khazaie ◽  
Javad Yoosefi Lebni ◽  
Jaffar Abbas ◽  
Behzad Mahaki ◽  
Fakhreddin Chaboksavar ◽  
...  
Keyword(s):  
Social Media ◽  
Standard Deviation ◽  
Medical Students ◽  
Internet Addiction ◽  
Technology Use ◽  
Standard Deviation Score ◽  
The Internet ◽  
Human Society ◽  
Cross Sectional ◽  
Internet And Social Media

Background In recent years, Internet and social media technology use have emerged as an integral tool of human society, and the evolution of technological integration, cyberspace, and web-technology has become a common practice in educational institutions. Internet usage among students has played an indispensable role in learning behavior; however, the excessive usage of the internet and social media leads to internet addiction. This original study has performed a focalized scrutiny on revealing relationships between internet addiction and associated factors among the students of medicine, dentistry, and pharmaceutical departments. Methods This descriptive and analytical study recruited medical students from the Self-governing Education Incubator of Kermanshah. This survey distributed questionnaires among the respondents’ three departments, and this statistical data reported on 420 valid responses of the respondents. They represent first and second-semester medical students of the academic year 2017–2018. The study selected medical students by applying Cochran's Sample Size Formula through Stratified Random Sampling and cross-sectional research design. The survey has utilized a demographic questionnaire of Young's Internet Addiction Test (IAT) for the data collection. The study analyzed received data by using SPSS version 23 and performed the descriptive statistics, and analytical statistics (t-test and ANOVA). Results The results of the present study established that the majority of subjects were female students (53.3%), and the average age was 23.84 ± 2.14, including the students of all departments. Besides, findings specified that the overall mean and standard deviation scores were 3.34 and ±0.88. Internet addiction revealed mean and the standard deviation score measured for all students 3.29 ± 0.73, 3.17 ± 0.92, and 3.57 ± 0.64 correspondingly. The survey results illustrated that medical students’ internet addiction substantially correlated with demographic variables, such as age, marital status, the field of study, academic term, significant time of consuming the internet, the key reason of utilizing the internet, and daily usage of the internet ( p < .05). Conclusion The results of the study specified that 25% of medical students showed internet addiction. The students are increasingly using the internet, and it has penetrated among students. The design and implementation of adequate educational programs and the application of internet-based efficiency interventions are essential for both knowledge acquisition and medical students’ healthy behavior.

scholarly journals An assessment of the quality indicators of operative and non-operative times in a public university hospital

2015 ◽  
Vol 13 (4) ◽  
pp. 594-599 ◽  
Author(s):  
Altair da Silva Costa Jr ◽  
Luiz Eduardo Villaça Leão ◽  
Maykon Anderson Pires de Novais ◽  
Paola Zucchi
Keyword(s):  
Standard Deviation ◽  
Operating Room ◽  
Operative Time ◽  
Patient Flow ◽  
Cross Sectional Study ◽  
Public University ◽  
Major Effect ◽  
University Hospital ◽  
Cross Sectional ◽  
Using Data

ABSTRACT Objective To assess the operative time indicators in a public university hospital. Methods A descriptive cross-sectional study was conducted using data from operating room database. The sample was obtained from January 2011 to January 2012. The operations performed in sequence in the same operating room, between 7:00 am and 5:00 pm, elective or emergency, were included. The procedures with incomplete data in the system were excluded, as well as the operations performed after 5:00 pm or on weekends or holidays. Results We measured the operative and non-operative time of 8,420 operations. The operative time (mean and standard deviation) of anesthesias and operations were 177.6±110 and 129.8±97.1 minutes, respectively. The total time of the patient in operative room (mean and standard deviation) was 196.8±113.2. The non-operative time, e.g., between the arrival of the patient and the onset of anesthesia was 14.3±17.3 minutes. The time to set the next patient in operating room was 119.8±79.6 minutes. Our total non-operative time was 155 minutes. Conclusion Delays frequently occurred in our operating room and had a major effect on patient flow and resource utilization. The non-operative time was longer than the operative time. It is possible to increase the operating room capacity by management and training of the professionals involved. The indicators provided a tool to improve operating room efficiency.

Cardioautonomic responses to acute ingestion of ice water and its correlation to body mass index

2018 ◽  
Vol 30 (2) ◽  
pp. 259-264
Author(s):  
Priya Arjunwadekar ◽  
Savitri Parvatgouda Siddanagoudra
Keyword(s):  
Body Mass Index ◽  
Standard Deviation ◽  
Body Mass ◽  
Water Intake ◽  
Healthy Subjects ◽  
P Value ◽  
Cross Sectional ◽  
Water Ingestion ◽  
Obese Subjects ◽  
Ice Water

Abstract Background A significant relationship has been documented in the literature between the autonomic nervous system imbalance and cardiovascular mortality. In patients with autonomic failure, water ingestion has been shown to increase blood pressure (BP), induce bradycardia, and cause low heart rate variability (HRV). A few studies showed the altered HRV as an acute effect of ice water intake in healthy subjects. None of the studies have shown light on the relationship of BP and HRV to ice water intake in obese and overweight subjects. The present study is aimed to correlate BP and HRV with body mass index (BMI) after ice water ingestion. Methods This cross-sectional study included a total of 60 subjects of both sexes aged between 18 and 24 years old. Subjects were assigned into three groups based on their BMI: normal, overweight, and obese. Before and after ice water ingestion, BP and HRV parameters were recorded and compared between the groups. Statistically data were analyzed by Student’s paired t-test and one-way analysis of variance. Results Basal HF was significant (p<0.05) in all three groups after ice water ingestion [F(2, 27), 44.1; p-value, 0.02]. After ice water ingestion, all HRV values were significant (p<0.001) in the three groups. The post-hoc Tukey HSD test demonstrated the less mean score for mean RR interval, standard deviation of all NN interval, standard deviation of differences between adjacent, HF and high for HR, LF, and LHR in overweight and obese subjects. Conclusions Because of the effective buffering system, healthy subjects showed increased HR and unchanged BP. Overweight and obese subjects showed decreased HR and increased BP.

scholarly journals Analisis Total Electron Content (TEC) Menggunakan Continous Wavelet Transform Sebagai Indikator Prekursor Gempa Bumi Di Wilayah Provinsi Bengkulu

2019 ◽  
Vol 9 (2) ◽  
pp. 27-33
Author(s):  
Laksamana Agung Aprillo ◽  
Hendy Santosa ◽  
Faisal Hadi
Keyword(s):  
Wavelet Transform ◽  
Standard Deviation ◽  
Total Electron Content ◽  
Electromagnetic Waves ◽  
Electron Content ◽  
Observation Data ◽  
Dual Frequency ◽  
Total Electron ◽  
Gps Observation ◽  
Large Earthquakes

ABSTRACT Bengkulu is one of 34 provinces in Indonesia which is a megathrust region. So Bengkulu province is often hit by many large earthquakes with shallow depth. TEC anomaly was analyzed based on three electromagnetic waves radiated by an earthquake. The total electron content (TEC) anomaly is seen through the global positioning system (GPS) dual-frequency radio signal data. The continuous wavelet transform (CWT) method is used to divide the signal analysis into several sections according to the electromagnetic wave frequency range of acoustic (2.5 mHz) -3 mHz), gravity waves (1 mHz-2.8 mHz) and rayleigh waves (5 mHz-33 mHz). GPS observation data for 9 days is calculated using the Standard deviation (2?) method to see trends in data changes. The analysis shows anomalies in the September 12 2007 earthquake (7.9 Mw), the March 5 2010 earthquake (6.3 Mw) and the August 4 2011 earthquake (6.0 Mw). Anomalies are detected 1 to 5 hours before an earthquake occurs. TEC anomalies that occur may be related to the process of preseismic before the earthquake and may be an early sign of an earthquake.Keyword: earthquake, total electron content, continous wavelet transform, standard deviation

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