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Efficacy of relaxation techniques in reducing preoperative anxiety and fear in general surgery patients:A quasi-experimental study
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作者 Seyed Ali RAZAVINASAB Batool ZEIDABADI +3 位作者 Reza SADEGH Iman NOSRATABADI Parniya ABOLGHASEMINEJAD Mohammd Moqaddasi AMIRI 《Journal of Integrative Nursing》 2025年第4期211-218,共8页
Objective:The study aimed to investigate the effect of relaxation techniques in reducing fear and anxiety in patients in need of general surgery.Materials and Methods:This quasi-experimental study with a pre-post cont... Objective:The study aimed to investigate the effect of relaxation techniques in reducing fear and anxiety in patients in need of general surgery.Materials and Methods:This quasi-experimental study with a pre-post control group design was conducted on 120 patients requiring general surgery at Saman Al-Hojjaj Hospital in Sirjan County.Patients were selected using convenience sampling and randomly assigned to the intervention group(n=60)and control group(n=60).The intervention group was taught box breathing and progressive muscle relaxation techniques by a senior psychiatric nursing expert for 15-20 min every 4 h until surgery.The control group received routine care for surgery.Data on fear and anxiety outcomes were collected using the Spielberger State-Trait Anxiety Inventory and the Surgical Fear Questionnaire.Results:The intervention group had a mean total fear score of 29.27±12.69 compared to 37.20±16.39 in the control group(P=0.012),with significant reductions in both short-term(13.57±5.93 vs.15.98±8.90;P=0.209,Cohen’s d=0.32)and long-term(15.70±7.19 vs.21.22±9.11;P=0.001,Cohen’s d=0.66)fear components(total fear:P=0.012,Cohen’s d=0.54).The total anxiety score was 91.88±6.28 in the control group and 93.60±3.62 in the intervention group,with trait anxiety significantly reduced in the intervention group(P=0.039,Cohen’s d=0.41)postintervention,but no significant change in state anxiety(P=0.577,Cohen’s d=0.16).Conclusions:Relaxation techniques significantly alleviate preoperative psychological distress,effectively reducing fear and anxiety in general surgery patients.These cost-effective,non-invasive methods enhance recovery and reduce healthcare costs.We recommend training healthcare providers to implement these techniques for optimal patient outcomes. 展开更多
关键词 ANXIETY FEAR general surgery psychological distress relaxation techniques
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Combination of terrestrial reference frames based on space geodetic techniques in SHAO:methodology and main issues 被引量:2
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作者 Bing He Xiao-Ya Wang +1 位作者 Xiao-Gong Hu Qun-He Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第9期1-14,共14页
Based on years of input from the four geodetic techniques (SLR, GPS, VLBI and DORIS), the strategies of the combination were studied in SHAO to generate a new global terrestrial reference frame as the material reali... Based on years of input from the four geodetic techniques (SLR, GPS, VLBI and DORIS), the strategies of the combination were studied in SHAO to generate a new global terrestrial reference frame as the material realization of the ITRS defined in IERS Conventions. The main input includes the time series of weekly solutions (or fortnightly for SLR 1983-1993) of observational data for satellite techniques and session-wise normal equations for VLBI. The set of estimated unknowns includes 3- dimensional Cartesian coordinates at the reference epoch 2005.0 of the stations distributed globally and their rates as well as the time series of consistent Earth Orientation Parameters (EOPs) at the same epochs as the input. Besides the final solution, namely SOL-2, generated by using all the inputs before 2015.0 obtained from short-term observation processing, another reference solution, namely SOL- 1, was also computed by using the input before 2009.0 based on the same combination of procedures for the purpose of comparison with ITRF2008 and DTRF2008 and for evaluating the effect of the latest six more years of data on the combined results. The estimated accuracy of the x-component and y-component of the SOL- 1 TRF-origin was better than 0.1 mm at epoch 2005.0 and better than 0.3 mm yr- 1 in time evolution, either compared with ITRF2008 or DTRF2008. However, the z-component of the translation parameters from SOL-1 to ITRF2008 and DTRF2008 were 3.4 mm and -1.0 ram, respectively. It seems that the z-component of the SOL-1 TRF-origin was much closer to the one in DTRF2008 than the one in ITRF2008. The translation parameters from SOL-2 to ITRF2014 were 2.2, -1.8 and 0.9 mm in the x-, y- and z-components respectively with rates smaller than 0.4 mmyr-1. Similarly, the scale factor transformed from SOL-1 to DTRF2008 was much smaller than that to ITRF2008. The scale parameter from SOL-2 to ITRF2014 was -0.31 ppb with a rate lower than 0.01 ppb yr-1. The external precision (WRMS) compared with IERS EOP 08 C04 of the combined EOP series was smaller than 0.06 mas for the polar motions, smaller than 0.01 ms for the UT1-UTC and smaller than 0.02 ms for the LODs. The precision of the EOPs in SOL-2 was slightly higher than that of SOL-1. 展开更多
关键词 astrometry w reference systems -- techniques interferometers -- methods: data analysis
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Power Ratio Gain Technique and General Integral Control
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作者 Baishun Liu 《Applied Mathematics》 2015年第4期663-669,共7页
In conjunction with general integral control, and synthesizing Singular perturbation and Equal ratio gain techniques, this paper proposes a new control design technique, named Power ratio gain technique, and then by L... In conjunction with general integral control, and synthesizing Singular perturbation and Equal ratio gain techniques, this paper proposes a new control design technique, named Power ratio gain technique, and then by Lyapunov method, theorem to ensure regionally as well as semi-globally asymptotic stability is established in terms of some bounded information. The highlight point is that it not only inherits all the essences of Singular perturbation and Equal ratio gain techniques but also makes up for their shortcomings, and then the conservatism of control input can be improved by compromising the Power ratio coefficients. Theoretical analysis, design example and simulation results show that Power ratio gain technique is a simple, practical and powerful tool to deal with the uncertain nonlinear system. 展开更多
关键词 general Integral CONTROL Nonlinear CONTROL Robust CONTROL Equal RATIO GAIN techniquE SINGULAR Perturbation techniquE Power RATIO GAIN techniquE Output Regulation
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Molecular biology techniques for the surgeon
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作者 Gopal Kowdley Subramanya Srikantan +2 位作者 Kotb Abdelmohsen Myriam Gorospe Javeed Khan 《World Journal of Surgical Procedures》 2012年第2期5-15,共11页
New technologies are constantly being introduced into the medical and surgical fields. These technologies come in the form of newer medicines, imaging methods and prognostic tools, among others, and allow clinicians t... New technologies are constantly being introduced into the medical and surgical fields. These technologies come in the form of newer medicines, imaging methods and prognostic tools, among others, and allow clinicians to make more rational and informed decisions on the care of their patients. Many of these technologies utilize advanced techniques which are at the forefront of many research fields and represent a transition of bench advances into the clinical realm. This review will highlight four technologies that are at the forefront in the treatment of oncology patients treated by surgeons on a daily basis. Circulating tumor cells, microarray analysis, proteomic studies and rapid sequencing technologies will be highlighted. These technologies will be reviewed and their potential use in the care o surgical patients will be discussed. 展开更多
关键词 Methods Molecular DIAGNOSTIC techniques Medical ONCOLOGY general surgery MT
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Equal Ratio Gain Technique and Its Application in Linear General Integral Control
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作者 Baishun Liu 《International Journal of Modern Nonlinear Theory and Application》 2015年第1期21-36,共16页
In conjunction with linear general integral control, this paper proposes a fire-new control design technique, named Equal ratio gain technique, and then develops two kinds of control design methods, that is, Decomposi... In conjunction with linear general integral control, this paper proposes a fire-new control design technique, named Equal ratio gain technique, and then develops two kinds of control design methods, that is, Decomposition and Synthetic methods, for a class of uncertain nonlinear system. By Routh’s stability criterion, we demonstrate that a canonical system matrix can be designed to be always Hurwitz as any row controller gains, or controller and its integrator gains increase with the same ratio. By solving Lyapunov equation, we demonstrate that as any row controller gains, or controller and its integrator gains of a canonical system matrix tend to infinity with the same ratio, if it is always Hurwitz, and then the same row solutions of Lyapunov equation all tend to zero. By Equal ratio gain technique and Lyapunov method, theorems to ensure semi-globally asymptotic stability are established in terms of some bounded information. Moreover, the striking robustness of linear general integral control and PID control is clearly illustrated by Equal ratio gain technique. Theoretical analysis, design example and simulation results showed that Equal ratio gain technique is a powerful tool to solve the control design problem of uncertain nonlinear system. 展开更多
关键词 Equal RATIO GAIN techniquE general INTEGRAL CONTROL Nonlinear CONTROL Robust CONTROL OUTPUT Regulation
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Nonlinear General Integral Control Design via Equal Ratio Gain Technique
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作者 Baishun Liu 《International Journal of Modern Nonlinear Theory and Application》 2014年第5期256-266,共11页
This paper proposes two kinds of nonlinear general integral controllers, that is, one is generic and another is practical, for a class of uncertain nonlinear system. By extending equal ratio gain technique to a canoni... This paper proposes two kinds of nonlinear general integral controllers, that is, one is generic and another is practical, for a class of uncertain nonlinear system. By extending equal ratio gain technique to a canonical interval system matrix and using Lyapunov method, theorems to ensure regionally as well as semi-globally asymptotic stability are established in terms of some bounded information. Moreover, for the practical nonlinear integral controller, a real time method to evaluate the equal ratio coefficient is proposed such that its value can be chosen moderately. Theoretical analysis and simulation results demonstrated that not only nonlinear general integral control can effectively deal with the uncertain nonlinear system but also equal ratio gain technique is a powerful and practical tool to solve the control design problem of dynamics with the nonlinear and uncertain actions. 展开更多
关键词 general Integral CONTROL NONLINEAR CONTROL Robust CONTROL Generic Controller Equal RATIO GAIN techniquE Output Regulation
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Lumbar-Sacral Plexus Block Anesthesia versus General Anesthesia for Total Hip Arthroplasty: Case Control Study 被引量:3
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作者 Perales Caldera Eduardo González Lumbreras Aniza Surinam +4 位作者 Uribe Campo Giselle Andrea Fernández Soto José Rodrigo Medina de la Rosa Edoardo Díaz Borjón Efraín Bravo Reyna Carlos César 《Open Journal of Anesthesiology》 2021年第9期259-268,共10页
<b>Background:</b> Peripheral block techniques for total hip arthroplasty have been used as an analgesic strategy, only a few studies described it as an anesthetic technique, so the perioperative performan... <b>Background:</b> Peripheral block techniques for total hip arthroplasty have been used as an analgesic strategy, only a few studies described it as an anesthetic technique, so the perioperative performance and safety are poorly studied. <b>Methods:</b> 78 total hip arthroplasties were prospectively observed in our hospital. Divided into 2 groups: 1) General anesthesia;and 2) Lumbar sacral plexus block anesthesia. Variables measured in both groups were: demographics, conversion to general anesthesia, total opioid doses, surgical time, blood loss, postoperative pain, use and total dose of vasopressors drugs, transfusion and ICU transfer needs, postoperative ambulation time, and length of hospital stay. T student and chi-square tests were used upon the case. A significant difference was considered when a value of p < 0.05 was obtained. Descriptive statistics were performed in frequency, percentages, variance and standard deviation. <b>Results:</b> 3 patients (7.3%) anesthetized with combined lumbar sacral plexus block were converted to general anesthesia. When comparing peripheral nerve block and general anesthesia, less intraoperative (p = 0.000) and postoperative (p = 0.002) opioid consumption were noted, less postoperative pain in PACU (p = 0.002) and in the first 24 hours (p = 0.005), as well as earlier onset of ambulation (p = 0.008) and shorter hospital stay (p = 0.031). <b>Conclusions:</b> In our study, the lumbar and sacral plexus block anesthesia technique provided anesthetic conditions to perform hip joint arthroplasty and it was proved to be advantageous in comparison to general anesthesia. 展开更多
关键词 Anesthetic technique Conversion Opioids Requirements general Anesthesia Regional Anesthesia Lumbar Plexus Block Sacral Plexus Block Lumbar Sacral Plexus Anesthesia Success Rate
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An improved astrometric calibration technique for space debris observation
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作者 Rong-Yu Sun Chang-Yin Zhao Yao Lu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第2期81-88,共8页
An optical survey is the main technique for detecting space debris. Due to the specific character- istics of observation, the pointing errors and tracking errors of the telescope as well as image degradation may be si... An optical survey is the main technique for detecting space debris. Due to the specific character- istics of observation, the pointing errors and tracking errors of the telescope as well as image degradation may be significant, which make it difficult for astrometric calibration. Here we present an improved method that corrects the pointing and tracking errors, and measures the image position precisely. The pipeline is tested on a number of CCD images obtained from a 1-m telescope administered by Xinjiang Astronomical Observatory while observing a GPS satellite. The results show that the position measurement error of the background stars is around 0.1 pixel, while the time cost for a single frame is about 7.5 s; hence the relia- bility and accuracy of our method are demonstrated. In addition, our method shows a versatile and feasible way to perform space debris observation utilizing non-dedicated telescopes, which means more sensors could be involved and the ability to perform surveys could be improved. 展开更多
关键词 techniques image processing -- space vehicles -- astrometry -- methods data analysis
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The Fifth Edition of the General Catalogue of Variable Stars:experiences in the constellation Centaurus
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作者 Nikolay N.Samus Elena N.Pastukhova +1 位作者 Olga V.Durlevich Elena V.Kazarovets 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第7期93-100,共8页
We have recently announced that the General Catalogue of Variable Stars enters the stage of its fifth, purely electronic edition (GCVS 5.1). We have included 1408 variable stars in the constellation Centaurus in thi... We have recently announced that the General Catalogue of Variable Stars enters the stage of its fifth, purely electronic edition (GCVS 5.1). We have included 1408 variable stars in the constellation Centaurus in this new version, GCVS 5.1. Working on this revision, we applied current possibilities from data mining, suggested new variability types for many variable stars and found new light elements for a large number of periodic variables. This paper describes the work completed during the preparation of GCVS 5.1 for Centaurus and discusses in detail a number of the most astrophysically significant cases. 展开更多
关键词 catalogs - techniques photometric - stars variables general - binaries ECLIPSING
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EXISTENCE AND ALGORITHM OF SOLUTIONS FOR GENERAL MULTIVALUED MIXED IMPLICIT QUASI-VARIATIONAL INEQUALITIES
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作者 曾六川 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第11期1324-1333,共10页
A new class of general multivalued mixed implicit quasi-variational inequalities in a real Hilbert space was introduced, which includes the known class of generalized mixed implicit quasi-variational inequalities as a... A new class of general multivalued mixed implicit quasi-variational inequalities in a real Hilbert space was introduced, which includes the known class of generalized mixed implicit quasi-variational inequalities as a special case , introduced and studied by Ding Xie-ping . The auxiliary variational principle technique was applied to solve this class of general multivalued mixed implicit quasi-variational inequalities. Firstly, a new auxiliary variational inequality with a proper convex , lower semicontinuous , binary functional was defined and a suitable functional was chosen so that its unique minimum point is equivalent to the solution of such an auxiliary variational inequality . Secondly , this auxiliary variational inequality was utilized to construct a new iterative algorithm for computing approximate solutions to general multivalued mixed implicit quasi-variational inequalities . Here , the equivalence guarantees that the algorithm can generate a sequence of approximate solutions. Finally, the existence of solutions and convergence of approximate solutions for general multivalued mixed implicit quasi-variational inequalities are proved. Moreover, the new convergerce criteria for the algorithm were provided. Therefore, the results give an affirmative answer to the open question raised by M. A . Noor, and extend and improve the earlier and recent results for various variational inequalities and complementarity problems including the corresponding results for mixed variational inequalities, mixed quasi-variational inequalities and quasi-complementarity problems involving the single-valued and set- valued mappings in the recent literature . 展开更多
关键词 general multivalued mixed implicit quasi-variational inequality auxiliary variational principle technique EXISTENCE algorithm
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General formula for phonon-assisted n-photon absorption in solids
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作者 邓洪祥 蒋晓东 +5 位作者 向霞 孙凯 袁晓东 郑万国 高飞 祖小涛 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期573-583,共11页
A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simpl... A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simply demonstrated by a diagram approach that is proposed in this work. We find that the transition element for the n-photon absorption has a simple form, i.e., it is just the first term of the n-th order fist kind Bessel function. 展开更多
关键词 general formula phonon-assisted photons absorption n order perturbation technique diagram approach intense laser
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A fast Stokes inversion technique based on quadratic regression
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作者 Fei Teng Yuan-Yong Deng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第5期7-16,共10页
Stokes inversion calculation is a key process in resolving polarization information on radiation from the Sun and obtaining the associated vector magnetic fields. Even in the cases of simple local thermo- dynamic equi... Stokes inversion calculation is a key process in resolving polarization information on radiation from the Sun and obtaining the associated vector magnetic fields. Even in the cases of simple local thermo- dynamic equilibrium (LTE) and where the Milne-Eddington approximation is valid, the inversion problem may not be easy to solve. The initial values for the iterations are important in handling the case with mul- tiple minima. In this paper, we develop a fast inversion technique without iterations. The time taken for computation is only 1/100 the time that the iterative algorithm takes. In addition, it can provide available initial values even in cases with lower spectral resolutions. This strategy is useful for a filter-type Stokes spectrograph, such as SDO/HMI and the developed two-dimensional real-time spectrograph (2DS). 展开更多
关键词 Sun: magnetic fields -- methods: statistical -- methods: data analysis -- techniques polari-metric
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Output Feedback Nonlinear General Integral Control
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作者 Baishun Liu 《International Journal of Modern Nonlinear Theory and Application》 2015年第2期101-116,共16页
This paper proposes an output feedback nonlinear general integral controller for a class of uncertain nonlinear system. By solving Lyapunov equation, we demonstrate a new proposition on Equal ratio gain technique. By ... This paper proposes an output feedback nonlinear general integral controller for a class of uncertain nonlinear system. By solving Lyapunov equation, we demonstrate a new proposition on Equal ratio gain technique. By using Equal ratio gain technique, Singular perturbation technique and Lyapunov method, theorem to ensure regionally as well as semi-globally exponential stability is established in terms of some bounded information. Moreover, a real time method to evaluate the ratio coefficients of controller and observer are proposed such that their values can be chosen moderately. Theoretical analysis and simulation results show that not only output feedback nonlinear general integral control has the striking robustness but also the organic combination of Equal ratio gain technique and Singular perturbation technique constitutes a powerful tool to solve the output feedback control design problem of dynamics with the nonlinear and uncertain actions. 展开更多
关键词 general INTEGRAL CONTROL Nonlinear CONTROL Robust CONTROL OUTPUT Feedback CONTROL Equal Ratio Gain techniquE SINGULAR Perturbation techniquE State Estimation INTEGRAL Observer OUTPUT Regulation
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Resection of high-grade glioma involving language areas assisted by multimodal techniques under general anesthesia:a retrospective study 被引量:1
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作者 Meng Cui Yukun Liu +6 位作者 Chunhui Zhou Hewen Chen Xin Gao Jiayu Liu Qingbao Guo Bing Guan Xiaodong Ma 《Chinese Neurosurgical Journal》 CAS CSCD 2023年第4期276-289,共14页
Background Multimodal techniques-assisted resection of glioma under general anesthesia(GA)has been shown to achieve similar clinical outcomes as awake craniotomy(AC)in some studies.In this study,we aim to validate the... Background Multimodal techniques-assisted resection of glioma under general anesthesia(GA)has been shown to achieve similar clinical outcomes as awake craniotomy(AC)in some studies.In this study,we aim to validate the use of multimodal techniques can achieve the maximal safe resection of high-grade glioma involving language areas(HGILAs)under GA.Methods HGILAs cases were reviewed and collected between January 2009 and December 2020 in our center.Patients were separated into multimodal group(using neuronavigation,intraoperative MRI combined with direct electrical stimulation[DES]and neuromonitoring[IONM])and conventional group(neuronavigation alone)and clinical outcomes were compared between groups.Studies of HGILAs were reviewed systematically and the meta-analysis results of previous(GA or AC)studies were compared with our results.Results Finally,there were 263 patients in multimodal group and 137 patients in conventional group.Compared to the conventional group,the multimodal group achieved the higher median EOR(100%versus 94.32%,P<0.001)and rate of gross total resection(GTR)(73.8%versus 36.5%,P<0.001)and the lower incidence of permanent language deficit(PLD)(9.5%versus 19.7%,P=0.004).The multimodal group achieved the longer median PFS(16.8 versus 10.3 months,P<0.001)and OS(23.7 versus 15.7 months,P<0.001)than the conventional group.The multimodal group achieved a higher rate of GTR than the cohorts in previous multimodal studies under GA and AC(73.8%versus 55.7%[95%CI 32.0-79.3%]versus 53.4%[35.5-71.2%]).The multimodal group had a lower incidence of PLD than the cohorts in previous multimodal studies under GA(9.5%versus 14.0%[5.8-22.1%])and our incidence of PLD was a little higher than that of previous multimodal studies under AC(9.5%versus 7.5%[3.7-11.2%]).Our multimodal group also achieved a relative longer survival than previous studies.Conclusions Surgery assisted by multimodal techniques can achieve maximal safe resection for HGILAs under GA.Further prospective studies are needed to compare GA with AC for HGILAs. 展开更多
关键词 High-grade glioma LANGUAGE Multimodal techniques Intraoperative MRI general anesthesia
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The Mini-SiTian Array:the Mini-SiTian Real-time Image Processing Pipeline(STRIP)
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作者 Hongrui Gu Yang Huang +10 位作者 Yongkang Sun Kai Xiao Zhirui Li Beichuan Wang Zhou Fan Chuanjie Zheng Henggeng Han Hu Zou Wenxiong Li Hong Wu Jifeng Liu 《Research in Astronomy and Astrophysics》 2025年第4期71-83,共13页
This paper provides a comprehensive introduction to the mini-Si Tian Real-time Image Processing pipeline(STRIP)and evaluates its operational performance.The STRIP pipeline is specifically designed for real-time alert ... This paper provides a comprehensive introduction to the mini-Si Tian Real-time Image Processing pipeline(STRIP)and evaluates its operational performance.The STRIP pipeline is specifically designed for real-time alert triggering and light curve generation for transient sources.By applying the STRIP pipeline to both simulated and real observational data of the Mini-Si Tian survey,it successfully identified various types of variable sources,including stellar flares,supernovae,variable stars,and asteroids,while meeting requirements of reduction speed within 5 minutes.For the real observational data set,the pipeline detected one flare event,127 variable stars,and14 asteroids from three monitored sky regions.Additionally,two data sets were generated:one,a real-bogus training data set comprising 218,818 training samples,and the other,a variable star light curve data set with 421instances.These data sets will be used to train machine learning algorithms,which are planned for future integration into STRIP. 展开更多
关键词 surveys techniques:photometric stars:variables:general techniques:image processing
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The Flash Spectrum Analysis during the 2013 Total Solar Eclipse
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作者 B.Q.Zhu Z.Xu C.Xiang 《Research in Astronomy and Astrophysics》 2025年第8期81-91,共11页
During the total solar eclipse of 2013 November 3, a fiber-based spectrometer captured the flash spectrum within the wavelength range of 5162–5325Å, with the field-of-view positioned approximately 0.04 R⊙above ... During the total solar eclipse of 2013 November 3, a fiber-based spectrometer captured the flash spectrum within the wavelength range of 5162–5325Å, with the field-of-view positioned approximately 0.04 R⊙above the east limb, near the second-contact point. This placement near the innermost corona, together with the nearby Baily's beads, enabled the detection of emission lines from the photosphere, lower chromosphere, and corona in the same spectral frame. The higher field-of-view made the coronal line Fe XIV 5303Åmore visible, while the reduced intensity of photospheric and lower chromospheric light, caused by terrestrial scattering, also influenced the observed spectrum. Meanwhile, we selected 18 flash emission lines to measure the ratio of the relative line height of the flash emission line to the relative line depth of the corresponding solar absorption line. This ratio serves as a diagnostic of the source function, minimizing opacity effects. Comparison of disk and flash spectra shows that this ratio increases for spectral lines at greater formation heights, being strongest for chromospheric lines(particularly Fe II), moderate for photospheric low-FIP lines, and weakest for photospheric neutral lines. This trend suggests a rising source function with formation height, potentially linked to increasing electron temperatures or influenced by factors observed in flash spectra near active regions as reported in earlier studies. 展开更多
关键词 techniques:spectroscopic ECLIPSES Sun:chromosphere Sun:photosphere Sun:general
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Detection of Emission Line Galaxies in the Slitless Spectra of HST and CSST
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作者 Kaiyuan Chen Shuairu Zhu +1 位作者 Linhua Jiang Zhenya Zheng 《Research in Astronomy and Astrophysics》 2025年第2期150-159,共10页
Slitless spectroscopy onboard space telescopes is a powerful tool to detect emission-line objects such as emissionline galaxies(ELGs)and quasars.In this work,we present a study of ELGs observed with slitless spectrosc... Slitless spectroscopy onboard space telescopes is a powerful tool to detect emission-line objects such as emissionline galaxies(ELGs)and quasars.In this work,we present a study of ELGs observed with slitless spectroscopy by the Hubble Space Telescope(HST)in a deep field of~44 arcmin^(2).This is one of the deepest HST fields with a wealth of imaging and spectral data.In particular,previous VLT/MUSE observations have covered this field and identified a large number of ELGs.We reduce the HST spectra using the latest pipeline with a forward modeling algorithm and construct a sample of ELGs.By comparing with the MUSE spectra,we characterize our ELG detection in the HST spectra,including the impact of the line flux,line width,signal-to-noise ratio,etc.We find that the morphological broadening may affect the detection of ELGs,such that more compact sources are easier to be detected in slitless spectra.We discuss its implications to future slitless spectroscopic surveys that will be carried out by the China Space Station Telescope(CSST)and find that the CSST slitless spectroscopy has a capability comparable to that of HST in terms of the detection of emission lines. 展开更多
关键词 techniques:spectroscopic surveys methods:data analysis galaxies:general galaxies:ISM
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From Detection to Parameters Estimation:A Pipeline for SDSS Photometric Images
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作者 Yu Mao Liangping Tu +5 位作者 Chaoran Yan Chenying Zhao Jiawei Miao Yue Jiang Zhengyang Xu Mingyu Zheng 《Research in Astronomy and Astrophysics》 2025年第11期141-154,共14页
Against the backdrop of massive sky survey data,the automated detection,classification,and parameter computation of targets have emerged as critical areas demanding urgent breakthroughs.However,in detection and classi... Against the backdrop of massive sky survey data,the automated detection,classification,and parameter computation of targets have emerged as critical areas demanding urgent breakthroughs.However,in detection and classification tasks,model accuracy is often constrained by issues such as small target sizes and insufficient feature information.To address this challenge,we innovatively constructs a fully automated astronomical image analysis pipeline that combines point source detection and classification,galaxy morphological classification,and parameter computation,forming an end-to-end solution.This pipeline achieves automated detection and morphological classification of both point sources and extended sources,and it is also able to compute the basic parameters of galaxy targets.The pipeline first accomplishes the detection and localization of target sources using the YOLOv9 model,and then leverages the optimized ResNet-AE model to initially categorize the detected targets into three major classes:stars,quasars,and galaxies.To tackle the problem of small sizes in some galaxy targets,we filtered out samples with larger sizes and distinct contours.Drawing on morphological characteristics,these samples were further classified into six categories via the DenseNet-SE4 model:barred spiral galaxies,cigar galaxies,elliptical galaxies,intermediate galaxies,spiral galaxies,and irregular galaxies.Following this classification,parameter computation was conducted on the targets.Experimental results show that the detection model has achieved better performance than previous studies,with a mean average precision of 85.20%at Intersection over Union values ranging from 0.5 to 0.95.Both classification models also reached an accuracy of over 85%on the test set.Compared with classical CNN networks,these two classification models boast higher precision,and the computation of target parameters has also yielded reliable outcomes.Experiments verify that this pipeline can act as a supplementary tool for astronomical image processing and be applied to data mining and analysis work in sky surveys. 展开更多
关键词 methods:data analysis techniques:image processing Galaxy:general
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Galaxy Morphology Classification Based on DenseNet-SE4 Algorithm
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作者 Yu Mao Liangping Tu +2 位作者 Zhenyang Xu Yue Jiang Mingyu Zheng 《Research in Astronomy and Astrophysics》 2025年第8期100-118,共19页
As massive amounts of image data are generated by large-scale sky survey projects, the importance of research on the morphological classification of galaxy images is growing increasingly. Deep learning, with the capab... As massive amounts of image data are generated by large-scale sky survey projects, the importance of research on the morphological classification of galaxy images is growing increasingly. Deep learning, with the capability of automatic feature extraction, exhibits remarkable performance in image classification algorithms. In the past, most of the excellent algorithm models proposed by astronomers focused on the classification of major categories and often ignored the subtle differences between galaxy categories. For this purpose, based on the DenseNet-121model, this paper attempts to introduce a variety of improvement strategies such as dynamic multi-scale convolution, learnable grouped convolution, and the squeeze-and-excitation module to optimize the performance of the model. After numerous exhaustive experimental comparisons, the DenseNet-SE4 network with excellent performance is proposed. Subsequently, we conduct comparative experiments between this network and multiple advanced convolutional models on the data set consisting of Galaxy10 DECaLS and GZD-5. We select the data of eight galaxy categories with similar morphologies, such as round smooth galaxies and barred spiral galaxies, to comprehensively test the classification ability of the model. The experimental results illustrate that the DenseNetSE4 network achieves an accuracy of 88.96%, a precision of 89.00%, a recall rate of 89.44%, and an F1-score of 89.21% on the test set, thus it has reached the highest level among the eight comparison algorithms. Moreover, the model was tested on data within different redshift intervals, demonstrating good robustness. Finally, the visualization method was employed to further validate the effectiveness and rationality of the DenseNet-SE4 network. 展开更多
关键词 methods:data analysis techniques:image processing galaxies:general
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LAMOST Medium-resolution Spectroscopic Survey of Galactic Open Clusters(LAMOST-MRS-O):An Overview of Survey Plan and Preliminary Results
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作者 Xi Zhang Chengzhi Liu +8 位作者 Jing Zhong Li Chen Ali Luo Jianrong Shi Chao Liu Jianjun Chen Haotong Zhang Jinliang Hou LAMOST MRS Collaboration 《Research in Astronomy and Astrophysics》 2025年第2期70-79,共10页
As part of the LAMOST medium-resolution spectroscopic survey,the LAMOST-MRS-O is a non-time domain survey that aims to perform medium-resolution spectral observations for member stars in the open cluster areas.This su... As part of the LAMOST medium-resolution spectroscopic survey,the LAMOST-MRS-O is a non-time domain survey that aims to perform medium-resolution spectral observations for member stars in the open cluster areas.This survey plans to obtain the spectroscopic parameters such as radial velocity and metal abundances of member stars and provide data support for further study on the chemical and dynamical characteristics and evolution of open clusters in combination with Gaia data.We have completed the observations on ten open cluster fields and obtained 235184 medium-resolution spectra of 133792 stars.Based on the data analyzed of LAMOST DR11v1.1,for some clusters of particular concern,it is found that the sampling ratio of members stars with Gmag<15 mag can reach 70%,which indicates that the LAMOST-MRS-O has reached our initial design goal. 展开更多
关键词 (Galaxy:)open clusters and associations:general techniques:spectroscopic surveys
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