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1.
Environ Monit Assess ; 193(3): 110, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33537901

RESUMO

Floods are one of the most disastrous and dangerous catastrophes faced by humanity for ages. Though mostly deemed a natural phenomenon, floods can be anthropogenic and can be equally devastating in modern times. Remote sensing with its non-evasive data availability and high temporal resolution stands unparalleled for flood mapping and modelling. Since floods in India occur mainly in monsoon months, optical remote sensing has limited applications in proper flood mapping owing to lesser number of cloud-free days. Remotely sensed microwave/synthetic aperture radar (SAR) data has penetration ability and has high temporal data availability, making it both weather independent and highly versatile for the study of floods. This study uses space-borne SAR data in C-band with VV (vertically emitted and vertically received) and VH (vertically emitted and horizontally received) polarization channels from Sentinel-1A satellite for SAR interferometry-based flood mapping and runoff modeling for Rupnagar (Punjab) floods of 2019. The flood maps were prepared using coherence-based thresholding, and digital elevation map (DEM) was prepared by correlating the unwrapped phase to elevation. The DEM was further used for Soil Conservation Service-curve number (SCS-CN)-based runoff modelling. The maximum runoff on 18 August 2019 was 350 mm while the average daily rainfall was 120 mm. The estimated runoff significantly correlated with the rainfall with an R2 statistics value of 0.93 for 18 August 2019. On 18 August 2019, Rupnagar saw the most devastating floods and waterlogging that submerged acres of land and displaced thousands of people.


Assuntos
Inundações , Radar , Monitoramento Ambiental , Humanos , Índia , Tecnologia de Sensoriamento Remoto , Rios
2.
J Environ Manage ; 277: 111393, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33075655

RESUMO

Among the input data of the watershed model for simulating changes of flowrate in the watershed, weather input data, especially input data related to rainfall, are the most important. Therefore, it is important to ensure the accuracy of rainfall input data to increase the accuracy of the watershed model results. Securing rainfall measurements with finer spatial and temporal resolutions is important in predicting flowrate variations at a sub-catchment, especially as they relate to global and local climate changes in weather conditions such as rainfall depth, rainfall intensity, etc. In this study, adjusted radar-rainfall estimates were suggested as alternative input data for watershed modeling. Through a statistical analysis of the representativeness of a ground rainfall measurement (10 km × 10 km grid), the necessity of radar-rainfall estimates (2 km × 2 km grid) was identified. By applying calibration factors to initial radar-rainfall estimates and comparing adjusted radar-rainfall estimates with ground rainfall measurements, it was proven that adjusted radar-rainfall estimates could be used as input data for watershed simulations (NSE > 0.92; n = 12). Adjusted radar-rainfall estimates and ground rainfall measurements were used as input data of the Soil and Water Assessment Tool model to predict flowrate variations at the outlets of a tributary and the entire watershed. As a result, the accuracies of the simulation results were improved for the outlets of a tributary and the entire watershed (NSE: 0.33 to 0.48 and 0.19 to 0.55, respectively). To obtain more reliable rainfall data, radar images easily accessible to users were applied, and the accuracy of the data was increased by applying simple equations to numerical data extracted from radar image processing. Additionally, the applicability of the adjusted radar-rainfall estimates was demonstrated by comparing the modeling results using the suggested rainfall data and existing ground-based rainfall data. The suggested methodologies are expected to contribute to more accurately predict the possibility of flood disasters in other regions and countries lacking infrastructure related to rainfall measurements and to establish appropriate countermeasures.


Assuntos
Radar , Chuva , Monitoramento Ambiental , Hidrologia , Meteorologia , Modelos Teóricos
3.
Mar Pollut Bull ; 162: 111921, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33341595

RESUMO

Four oil spill events over the Indian Ocean including Chennai, Sharjah, Al Khiran and Mubarak Village are analyzed using Sentinel-1 satellite data. General National Oceanic and Atmospheric Administration (NOAA) Operational Modeling Environment (GNOME) model is utilized for oil spills trajectory production, whereas oil spills weathering processes are modeled using Automated Data Inquiry for Oil Spill (ADIOS). Synthetic Aperture Radar (SAR) based oil spill detection technique provided reliable results at the wind speed between 3 to 9 m/s for all events. Maximum oil spill movement (33 km) from the source point is observed in the Al Khiran, whereas evaporation rate of crude (degraded) oil is observed as high (low). The Near Real Time (NRT) detection of oil spill using SAR imagery needs high computational power, however, provides better results. This study concludes that SAR based oil spill detection is a cost-effective technique and can be utilized for mapping of oil spills.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes Químicos da Água , Monitoramento Ambiental , Índia , Oceano Índico , Petróleo/análise , Poluição por Petróleo/análise , Radar , Poluentes Químicos da Água/análise
4.
PLoS One ; 15(12): e0243939, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33370375

RESUMO

BACKGROUND: Current cardiorespiratory monitoring equipment can cause injuries and infections in neonates with fragile skin. Impulse-radio ultra-wideband (IR-UWB) radar was recently demonstrated to be an effective contactless vital sign monitor in adults. The purpose of this study was to assess heart rates (HRs) and respiratory rates (RRs) in the neonatal intensive care unit (NICU) using IR-UWB radar and to evaluate its accuracy and reliability compared to conventional electrocardiography (ECG)/impedance pneumography (IPG). METHODS: The HR and RR were recorded in 34 neonates between 3 and 72 days of age during minimal movement (51 measurements in total) using IR-UWB radar (HRRd, RRRd) and ECG/IPG (HRECG, RRIPG) simultaneously. The radar signals were processed in real time using algorithms for neonates. Radar and ECG/IPG measurements were compared using concordance correlation coefficients (CCCs) and Bland-Altman plots. RESULTS: From the 34 neonates, 12,530 HR samples and 3,504 RR samples were measured. Both the HR and RR measured using the two methods were highly concordant when the neonates had minimal movements (CCC = 0.95 between the RRRd and RRIPG, CCC = 0.97 between the HRRd and HRECG). In the Bland-Altman plot, the mean biases were 0.17 breaths/min (95% limit of agreement [LOA] -7.0-7.3) between the RRRd and RRIPG and -0.23 bpm (95% LOA -5.3-4.8) between the HRRd and HRECG. Moreover, the agreement for the HR and RR measurements between the two modalities was consistently high regardless of neonate weight. CONCLUSIONS: A cardiorespiratory monitor using IR-UWB radar may provide accurate non-contact HR and RR estimates without wires and electrodes for neonates in the NICU.


Assuntos
Aptidão Cardiorrespiratória/fisiologia , Frequência Cardíaca/fisiologia , Monitorização Fisiológica , Taxa Respiratória/fisiologia , Eletrocardiografia/métodos , Estudos de Viabilidade , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Radar , Processamento de Sinais Assistido por Computador/instrumentação
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2646-2649, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018550

RESUMO

This paper reports a pilot study of a hybrid radar-camera system that simultaneously monitors the respiration of two subjects. A prototype system was built involving a low-cost impulse-radio ultra-wideband (IR-UWB) radar module and an optical and depth-sensing camera module. The system detects subjects using the camera and utilizes the distance information acquired to guide the signal processing of the radar. This structure simplifies subject identification and tracking for the radar system, provides further context to the radar, and facilitates the extraction of respiration information. Experiments under different scenarios were conducted to evaluate the performance of the system at different distances and angles from subjects. The localization procedure has an average accuracy of 0.1 m. The respiration rates extracted from the radar are comparable with the values from the reference wearable sensor, reporting an average error of 0.79 respirations per minute (RPM) with a standard deviation of 0.71 RPM. The results suggest that the respiration signals from subjects could be accurately monitored with the presented framework. It is also feasible to monitor two subjects at the same time in most scenarios. The proposed framework shows promising potential to work as a ubiquitous monitoring system for multiple subjects.


Assuntos
Eletrocardiografia , Radar , Monitorização Fisiológica , Projetos Piloto , Sistema Respiratório
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4183-4186, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018919

RESUMO

In this paper, a non-contact respiration detection scheme based on Doppler radar-depth camera sensor fusion has been proposed. A continuous-wave (CW) Doppler radar sensor and a depth camera are used to measure the respiratory motion separately. Then the Bayesian sensor fusion algorithm is used to estimate the cycle-to-cycle breathing rate. The experiments prove that the proposed fusion scheme can provide an accurate breathing rate estimation than using a single sensor. In particular, the proposed scheme can give a reasonable estimation even under the influence of body movement.


Assuntos
Radar , Respiração , Algoritmos , Teorema de Bayes , Taxa Respiratória
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5733-5736, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019276

RESUMO

Populations around the world are rapidly ageing. Age-friendly environments address the significance of continuous inhome vital sign monitoring. Impulse Radio Ultra-WideBand (IR-UWB) radar serves as a household healthcare assistance, providing non-contact vital sign monitoring without privacy issues and illumination limitation. However, the body movements bring difficulty in extracting heartbeat from radar signals, let alone obtaining complete information with body occlusions among multiple targets. This paper proposes a Multiple Moving Targets Heartbeat Estimation And Recovery (MMT-HEAR) approach to extract vital signs using IR-UWB radars. CLEAN and Joint Probability Data Association (JPDA) algorithms are firstly performed on each radar to estimate target-to-antenna distances of multiple targets. Considering signal obstruction and attenuation for targets occluded by others, the location-based distance optimization is proposed to refine these distances by combining information from all radars. Then the mapping from signal amplitudes to refined distances is introduced and combined with the Variational Nonlinear Chirp Mode Decomposition (VNCMD) to extract vital signs with body movements. To the best of our knowledge, this is the first attempt to monitor vital signs of multiple moving targets with radars. The averaging accuracy for two moving targets heartbeat monitoring during a 20-minutes observation is 85.93% with MMT-HEAR. Compared to two other conventional methods, the MMT-HEAR approach yields improvements of 16.11% and 10.16%, revealing the efficiency and robustness of this proposed approach.


Assuntos
Radar , Processamento de Sinais Assistido por Computador , Frequência Cardíaca , Compostos Organometálicos , Sinais Vitais
8.
PLoS One ; 15(10): e0239892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33002082

RESUMO

A detailed situation awareness of the local environment is essential for safe flight in General Aviation. When operating under Visual Flight Rules, eyesight is crucial for maintaining situation awareness and objects may be overlooked. Technical solutions such as Flarm have been sought, but they only work on a basis of co-operation: obstacles without the proper equipment are invisible. Recent developments in the field of radar technology, partly empowered by the demand for sensors for autonomous cars, have improved the size and power consumption of available hardware. Today, the hardware exists to build a portable primary radar system for situation awareness. In this paper the results are presented of efforts to build the first portable primary radar for general, which has to be lightweight, cheap and have a low power consumption. The focus in this paper is on the software design of such a radar system. The physical principles of radar sensing are described, as well as the scientific steps needed to provide situation awareness. The hardware and software for the radar are both built and tested, and the results of these tests are presented. A flight experiment is performed with a small aircraft flying past a stationary radar on a small hill. It is found that the radar is capable of detecting the aircraft up to a distance of at least 3 kilometers. 3D localization is performed and the location determined by the radar was on average 46 meters away from the aircraft position as measured by satellite navigation, relative to a total distance of about 1000 meters from the radar. A low-pass filter can be applied on the raw results in order to improve the location estimation further. Future research will focus on bringing the portable radar in motion while operating.


Assuntos
Aviação/instrumentação , Radar/instrumentação , Software/normas
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 477-480, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018031

RESUMO

The continuous-wave Doppler radar measures the movement of a chest surface including of cardiac and breathing signals and the body movement. The challenges associated with extracting cardiac information in the presence of respiration and body movement have not been addressed thus far. This paper presents a novel method based on the windowed-singular spectrum analysis (WSSA) for solving this issue. The algorithm consists of two processes: signal decomposition via WSSA followed by the reconstruction of decomposed heartbeat signals through convolution. An experiment was conducted to collect chest signals in 212 people by Doppler radar. In order to confirm the effect of reducing the large noise by the proposed method, we evaluated 136 signals that were considered to contain respiration body movements from the collected signals. When comparing to the performance of a band-pass filter, the proposed analysis achieves improved beat count accuracy. The results indicate its applicability to contactless heartbeat estimation under involving respiration and body movements.


Assuntos
Radar , Processamento de Sinais Assistido por Computador , Frequência Cardíaca , Humanos , Respiração , Análise Espectral
10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 481-484, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018032

RESUMO

A novel respiratory signal detection system capable of simultaneously tracking the position of the subject and detecting his or her respiratory signal is described. The monitoring system consists of depth camera with ultra wide band radar device. Both sensors are connected through a mini computer, which performs data acquisition and storage. In this paper, we propose a method to locate the position of the subject where he or she is lying in the bed covered with blanket. Mask R-CNN is used to help segment upper-body's silhouette and give out the center point distance. The distance between the camera and the subject is then converted into a range bin of the radar and the breath-like signal is extracted from that range- bin. Additional contribution of this paper is that we developed a classifier to classify the whether the extracted signal in the selected range bin is indeed a breathing signal or not.


Assuntos
Algoritmos , Radar , Feminino , Masculino , Monitorização Fisiológica , Respiração
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 485-488, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018033

RESUMO

Utilizing Impulse Radio Ultra-WideBand (IR-UWB) radar for vital sign monitoring has attracted growing interest due to the noncontact measurement without privacy concerns. Most of existing researches assume that the subject's chest is directed to the radar antenna, to ensure the strength of backscattered signals from chest movement. However, a large angle between the antenna and the subject's chest caused by the body orientation badly affects the monitoring accuracy. Multiple observations of the same cardiopulmonary activity from different orientations provide more available measurements. This paper addresses the challenge by using an IR-UWB radar network instead of a single radar. Three IR-UWB radars are placed as endpoints of an equilateral triangle to collect vital sign information of a subject sitting at the center. A Conditional Generative Adversarial Network (CGAN) method is proposed to fuse multisensory data. First, the body orientation is classified by combining signal features and a random forest classifier. Then the impact of different angles on vital sign monitoring results is discussed and validated in each orientation. The data fusion process is modelled as an extended generative network with orientation based condition to produce the enhanced vital signal. This signal is optimized with the discriminator network to a fitted sinusoidal wave with heartbeat and respiratory information. Experimental results on measuring Heartbeat Rate (HR) in different orientations reveal the effectiveness and stability of the proposed method.


Assuntos
Radar , Processamento de Sinais Assistido por Computador , Coração , Frequência Cardíaca , Respiração
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 489-493, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018034

RESUMO

Respiratory rate (RR) is one of the vital signs which is commonly measured by contact-based methods, such as using a breathing belt. Recently, significant research has been conducted related to contactless RR monitoring - however, the majority of experiments are performed in situations when the subject is oriented towards the radar. In this research, we are interested in monitoring the breathing of subjects who can be anywhere in the room. A system of three impulse radio ultrawideband (IR-UWB) radars is used to cover the whole room. A Kinect camera that can track subjects' joints 3D coordinates was employed to localize the subjects. The results of RR monitoring using IR-UWB radars and Kinect camera show good performance in single/multiple subject(s) tracking and RR estimation.


Assuntos
Taxa Respiratória , Processamento de Sinais Assistido por Computador , Algoritmos , Humanos , Radar , Sinais Vitais
13.
Sci Data ; 7(1): 291, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901032

RESUMO

Using Radar it is possible to measure vital signs through clothing or a mattress from the distance. This allows for a very comfortable way of continuous monitoring in hospitals or home environments. The dataset presented in this article consists of 24 h of synchronised data from a radar and a reference device. The implemented continuous wave radar system is based on the Six-Port technology and operates at 24 GHz in the ISM band. The reference device simultaneously measures electrocardiogram, impedance cardiogram and non-invasive continuous blood pressure. 30 healthy subjects were measured by physicians according to a predefined protocol. The radar was focused on the chest while the subjects were lying on a tilt table wired to the reference monitoring device. In this manner five scenarios were conducted, the majority of them aimed to trigger hemodynamics and the autonomic nervous system of the subjects. Using the database, algorithms for respiratory or cardiovascular analysis can be developed and a better understanding of the characteristics of the radar-recorded vital signs can be gained.


Assuntos
Monitorização Ambulatorial/instrumentação , Radar , Sinais Vitais , Algoritmos , Sistema Nervoso Autônomo , Voluntários Saudáveis , Hemodinâmica , Humanos
14.
Environ Monit Assess ; 192(9): 559, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32747987

RESUMO

This article aims to analyze the dynamics of freezing and thawing of Antarctic lakes located in ice-free areas on Nelson Island and Fildes Peninsula, where response to changes in air temperature and precipitation rates occur rapidly, during the period from July 2016 to December 2018. In these places, which are difficult to access, remote sensing is an important alternative, especially considering the use of active remote sensors such as the Synthetic Aperture Radar (SAR), which has less restriction regarding the presence of clouds over the study area. Three backscatter thresholds were defined (σ) for the identification of the physical state of the water of the lakes of the study region, applied in Sentinel 1A SAR (S1A) images under Horizontal Horizontal (HH) polarization and Interferometric Wide (IW) imaging mode. These images, along with the air temperature data obtained by the Interim Re-Analysis (ERA-Interim) atmospheric reanalysis model, provided the evidence for the interpretation of the freezing and thawing periods of the lakes. The thresholds applied for the definition of the physical state of the lake water were greater than - 14 dB for frozen water, between - 14 and - 17 dB for the surface, with up to 60% of their frozen area, and less than - 17 dB for open water. The temporal analysis revealed that the lakes start to thaw in October, become completely thawed in February, and freeze again in March. Nevertheless, it can be said that the S1A satellite allows a satisfactory identification of the liquid and solid phases of the water in the lakes of the study region.


Assuntos
Lagos , Radar , Regiões Antárticas , Monitoramento Ambiental , Congelamento , Ilhas
15.
J Med Syst ; 44(10): 177, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32845385

RESUMO

BACKGROUND: The outbreak of Coronavirus disease (COVID-19) pandemic has become the most serious global health issue. Isolation policy in hospitals is one of the most crucial protocols to prevent nosocomial infection of COVID-19. It is important to monitor and assess the physical conditions of the patients in isolation. METHODS: Our institution has installed the novel non-contact wireless sensor for vital sign sensing and body movement monitoring for patients in COVID-19 isolation ward. RESULTS: We have collected and compared data between the radar record with the nurse's handover record of two patients, one recorded for 13 days and the other recorded for 5 days. The P value by Fisher's exact test were 0.139 (temperature, P > 0.05) and 0.292 (heart beat rate, P > 0.05) respectively. CONCLUSIONS: This is the first report about the application experience of this equipment. Therefore we attempted to share the experience and try to apply this equipment in COVID-19 patients in future to offer the more reliable and safe policy.


Assuntos
Infecções por Coronavirus/epidemiologia , Monitorização Fisiológica/instrumentação , Pneumonia Viral/epidemiologia , Radar/instrumentação , Telemetria/instrumentação , Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Infecção Hospitalar/prevenção & controle , Administração Hospitalar , Humanos , Movimento , Pandemias/prevenção & controle , Isolamento de Pacientes , Pneumonia Viral/prevenção & controle
16.
Environ Monit Assess ; 192(9): 584, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32808098

RESUMO

In this study, we investigate stand-alone and combined Pleiades high-resolution passive optical and ALOS PALSAR active Synthetic Aperture Radar (SAR) satellite imagery for aboveground biomass (AGB) estimation in subtropical mountainous Chir Pine (Pinus roxburghii) forest in Murree Forest Division, Punjab, Pakistan. Spectral vegetation indices (NDVI, SAVI, etc.) and sigma nought HV-polarization backscatter dB values are derived from processing optical and SAR datasets, respectively, and modeled against field-measured AGB values through various regression models (linear, nonlinear, multi-linear). For combination of multiple spectral indices, NDVI, TNDVI, and MSAVI2 performed the best with model R2/RMSE values of 0.86/47.3 tons/ha. AGB modeling with SAR sigma nought dB values gives low model R2 value of 0.39. The multi-linear combination of SAR sigma nought dB values with spectral indices exhibits more variability as compared with the combined spectral indices model. The Leave-One-Out-Cross-Validation (LOOCV) results follow closely the behavior of the model statistics. SAR data reaches AGB saturation at around 120-140 tons/ha, with the region of high sensitivity around 50-130 tons/ha; the SAR-derived AGB results show clear underestimation at higher AGB values. The models involving only spectral indices underestimate AGB at low values (< 60 tons/ha). This study presents biomass estimation maps of the Chir Pine forest in the study area and also the suitability of optical and SAR satellite imagery for estimating various biomass ranges. The results of this work can be utilized towards environmental monitoring and policy-level applications, including forest ecosystem management, environmental impact assessment, and performance-based REDD+ payment distribution.


Assuntos
Pinus , Radar , Biomassa , Ecossistema , Monitoramento Ambiental , Florestas , Paquistão , Tecnologia de Sensoriamento Remoto
17.
Artigo em Chinês | MEDLINE | ID: mdl-32791641

RESUMO

Objective:To compare the effect of impulse-radio ultrawideband(IR-UWB) radar technology and polysomnography(PSG) in sleep assessment. Method:A total of 79 OSA patients were randomly divided into two groups: 40 patients in group A received PSG and IR-UWB, and 39 patients in group B received micromovement sensitive mattress(MSM) and IR-UWB. Pearson correlation and ROC curve were used for statistics. Result:AHI PSG and AHI MSM were significantly correlated with AHI IR-UWB(r=0.91, P=0.00; r=0.92, P=0.00). Bland-Altman analysis showed that AHI IR-UWB value was highly consistent with AHI PSG value(95.00%), and AHI IR-UWB value(97.44%). The sensitivity and specificity of AHI IR-UWB compared with PSG were 70.40% and 89.90%, respectively. The area under ROC curve was 0.915. Conclusion:IR-UWB has a high diagnostic value for adult OSA in terms of minimum blood oxygen saturation, average blood oxygen saturation, average number of central sleep apnea, average number of complex sleep apnea, average heart rate, sleep efficiency, REM sleep duration, average AHI, etc. It is an economic and practical sleep evaluation tool.


Assuntos
Minorias Sexuais e de Gênero , Apneia Obstrutiva do Sono , Adulto , Homossexualidade Masculina , Humanos , Masculino , Polissonografia , Radar , Sensibilidade e Especificidade
18.
Am Surg ; 86(8): 1029-1031, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32721172

RESUMO

BACKGROUND: Breast cancer is the most commonly diagnosed noncutaneous malignancy and remains the second leading cause of cancer deaths in women. The Savi Scout (Cianna Medical, Merit Medical Systems, Inc. South Jordan, UT) is a wireless, nonradioactive, wave reflection implant system that enables surgeons to remove targeted breast lesions. Our study aims to be the largest comparison of wire and Savi Scout localization techniques for positive margin, complication, and reoperation rates. METHODS: Single-institution retrospective review of 512 patients that had Savi Scout Surgical Guidance System breast lesion biopsy or wire localized breast biopsy from May 2017 to December 2018. A RedCaps database was created and reviewed for outcomes. RESULTS: For 320 Savi scout patients, margins were positive or less than 1 mm in 18 cases (5.6%). 17 (5.3%) patients required reoperation. Surgical site occurrence was found in 7 (2.1%) patients, and 2 patients required intervention (0.6%). For 175 wire localization patients, margins were positive or less than 1 mm in 24 patients, and all required reoperation (13.7%). A surgical site occurrence was found in 13 (7.4%) patients and 5 patients required intervention (2.8%). DISCUSSION: In our series, the Savi Scout localization system resulted in a lower rate of positive margins, reoperation, and surgical site occurrence. These data suggest that Savi Scout localization is a reasonable replacement to wire localization for breast lesions and might produce superior results.


Assuntos
Neoplasias da Mama/cirurgia , Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Marcadores Fiduciais , Mastectomia Segmentar/métodos , Radar , Cirurgia Assistida por Computador/instrumentação , Adulto , Idoso , Biópsia , Mama/diagnóstico por imagem , Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Feminino , Humanos , Margens de Excisão , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Cirurgia Assistida por Computador/métodos
19.
PLoS One ; 15(7): e0235489, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697772

RESUMO

The ability to accurately measure the geometric characteristics of soil wetted bodies (SWBs) is very important for conserving water in agriculture. However, measurements of SWBs obtained using conventional methods have a number of defects. Ground penetrating radar (GPR) is a promising technique for detecting buried features. In this paper, we used GPR to nondestructively investigate SWBs formed under drip irrigation. First, numerical simulations were performed to obtain the theoretical radar-gram of SWBs. Then, controlled irrigation experiments were performed to obtain radar scan datasets in a laboratory. The GPR image was interpreted according to the numerical simulation results, and the SWB thickness detection accuracy was estimated. Finally, GPR detection was performed in the field with different irrigation volumes, and the detection effect was assessed. The GPR reflections in the laboratory and field measurements were more complex than in the numerical simulation images, but the location and thickness of SWBs were still clear; the accuracy of the measured thickness was high, and the accuracy decreased with an increase in irrigation volume. The radar image resolution and thickness accuracy measured in the field were slightly less than the values measured in the laboratory. Thus, GPR is able to quickly and accurately characterize SWBs formed by drip irrigation based on the thickness and relative position in the soil. Furthermore, the F-K offset transformation was an effective GPR data processing method for focusing reflections from SWBs to obtain their true position and physical extent.


Assuntos
Irrigação Agrícola , Monitoramento Ambiental/métodos , Radar , Solo
20.
Water Sci Technol ; 81(8): 1623-1635, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32644956

RESUMO

The performance of a new type of X-band weather radar (WR) for Sweden during a pilot run is studied. Compared to the conventional C-band WRs, the X-band WR covers a smaller area but with a higher spatiotemporal resolution, making it suitable for urban hydrological applications. Rainfall estimations from different elevation angles of the radar (levels) are compared at one-minute and single-event timescales with the observations of several rain gauges at different ranges using hyetographs. In general, the estimations aligned well with observations and the best match appeared for ranges as long as 5-10 km. Seemingly, radar estimations suffered from overshooting of lower lying showers by higher level scans in longer ranges (19-30 km) and from the reflectivity contamination due to moving objects in short ranges (<1 km). Also, the effective range of the radar dropped sharply for the moments when a cloudburst was located over the radar. Although various sources of error could affect the X-band WR rainfall estimates, higher resolution spatiotemporal rainfall monitoring for wider areas will benefit from an integration of data from a network of X-band WRs.


Assuntos
Monitoramento Ambiental , Radar , Chuva , Suécia , Tempo (Meteorologia)
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