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1.
Opt Express ; 32(6): 8555-8571, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38571112

ABSTRACT

The Risley prism's compact structure, dynamic responsiveness, and high tracking accuracy make it ideal for photoelectric image tracking. To realize fast and high-precision tracking of the target, we propose an image-based closed-loop tracking cascade control (IBCLTCR-F) system using a single image detector that integrates the Risley prism and fast steering mirror (FSM). Firstly, We propose a cascade control input-decoupling method (CCIDM) for the IBCLTCR-F system to solve the complex problem of coarse-fine control input decoupling in traditional single detector cascaded control systems. Moreover, the CCIDM method ensures that the FSM deflection angle is small and does not exceed its range during the fine tracking process, by using the Risley prism to compensate for the FSM deflection angle. Next, we design the image-based closed-loop tracking controllers of the Risley prism system and FSM system and analyze the stability of the IBCLTCR-F system. Finally, we track static and moving targets through experiments. The experimental results verify the feasibility of the IBCLTCR-F system, the effectiveness of the decoupling method, and the fast and high-precision tracking of the targets.

2.
Micromachines (Basel) ; 14(3)2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36984975

ABSTRACT

At present, the majority of sparse-aperture telescopes (SATs) are unable to observe moving targets. In this paper, we describe the construction of and present the results obtained using a Fizeau directly-imaging sparse-aperture telescope (FDISAT) that permits pointing and the tracking of moving targets. The telescope comprises three sub-apertures, each of which is equipped with a Risley prism system that permits a maximum tracking range of 5° and has independent boresight adjustment capability. On targets in various positions, experiments with pointing and tracking are conducted. The maximum root-mean-square error (RMSE) of pointing in the sub-apertures was found to be 8.22 arcsec. When considering a target moving at 0.01°/s for approximately 320 s, the maximum RMSE of tracking in the sub-apertures was found to be 4.23 arcsec. The images obtained from the focal plane detector exhibit clear interference fringes while tracking. The experimental results demonstrate that the system can effectively track moving targets, providing a method for SAT observation of moving targets.

3.
Micromachines (Basel) ; 13(12)2022 Nov 28.
Article in English | MEDLINE | ID: mdl-36557395

ABSTRACT

Image-based closed-loop tracking (IBCLT) is an important part of the process of target tracking. The Risley prism system has a unique advantage in improving the target tracking ability because of its compact and lightweight structure. Compared with traditional target tracking equipment, the Risley prism system has two difficulties in the process of IBCLT. First, the Risley prism is a complex coupling system of double input and double output. Second, the Risley prism itself is a nonlinear system. These problems lead to decrease in dynamic response and inconsistent target tracking capabilities. Thus, this paper proposes a method to implement multivariable decoupling and reduce the nonlinear effect. First, the boresight error of IBCLT is decoupled to the azimuth and elevation directions by the rotation matrix error-decoupling (RMED) method. Second, the gains of IBCLT in azimuth and elevation directions are independent variables that comes from two functions of the target elevation angle. The experimental results show that the IBCLT error deviation of different static targets in the field of view is within 0.025 arcsec, which is 70% lower compared with the fixed gain method. Furthermore, the steady-state error deviation of moving targets is controlled within 2.5 arcsec. These experimental results prove the feasibility and effectiveness of the proposed method.

4.
Appl Opt ; 60(16): 4798-4806, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34143032

ABSTRACT

In this paper, a cascade double-loop control (DLC) combined with modeling compensation methods is proposed to improve the tracking precision of the multiaperture imaging system (MAIS). The application of the flexible thin-wall ring mechanism in the coupling rotating prism (CRP) system causes a series of tracking and pointing challenges. Disturbances such as friction, shaft deformation, and model perturbation significantly deteriorate the tracking and pointing accuracy of the CRP. Two different modeling compensation methods that are interfaced with classical DLC are proposed to guarantee the tracking precision of the MAIS. Moreover, the disturbance observation and compensation performance of two different modeling compensation methods are analyzed and compared. Finally, simulation and experiment results indicate that the proposed control methods, especially model compensation based on speed close-loop control, obtain the best performance for disturbance rejection in the MAIS.

5.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-801415

ABSTRACT

Objective@#To understand the situation and genotype distribution of spotted fever group rickettsia (SFGR) in the border area of Tumen River Basin in free ticks in Yanbian Korean Autonomous Prefecture (Yanbian Prefecture), Jilin Province. @*Methods@#From April to September, 2017, ticks were collected using flagging method from Hunchun, Tumen, Helong and Longjing cities in the Tumen River basin of Yanbian Prefecture. Outer membrane protein A (ompA) was detected by Polymerase Chain Reaction (PCR), then, the species were identified by gene sequencing and analyzed systematically. The positive rate of pools and MIR(minimum infection rate per 100 ticks,MIR) of SFGR were calculated, and the difference of positive rate of pools among ticks with different characteristics was compared by Chi-square test. @*Results@#A total of 3 079 ticks were collected and divided into 536 pools. The positive rate of pools of SFGR nucleic acid was 39.7% (213 pools). The MIR of SFGR was 6.9%.The positive rate of pools of SFGR in Dermacentor silvarum, Haemaphysalis concinna, Haemaphysalis japonica, Haemaphysalis longicornis and Ixodes persulcatus were 80.4% (41/51), 14.0% (25/179), 20.2% (18/89), 78.9% (101/128) and 25.9% (21/81), and the difference was statistically significant (P<0.001). There was statistical difference in the positive rate of pools of SFGR in developmental stages of ticks (P<0.001); the positive rate of pools of female adults, male adults, nymph and larvae were 36.4% (95/261), 34.2% (67/196), 56.3% (40/71) and 7/8, and the MIR was 7.9%, 7.7%, 4.9% and 3.5%. The five genotype was detected which was Candidatus Rickettsia longicornii, Rickettsia raoultii, Rickettsia heilongjiangensis, Candidatus Rickettsia tarasevichiae,Rickettsia monacensis and have 98%-100% homology with known gene sequences. Candidatus Rickettsia longicornii, Rickettsia raoultii, Rickettsia heilongjiangensis and Candidatus Rickettsia tarasevichiae showed close evolutionary relationship with known specie (have 98%-100% homology with known gene sequences); Rickettsia monacensis showed Far from evolutionary relationship with known species (have 98% homology with known gene sequences). @*Conclusion@#SFGR infection of ticks is common in the border areas of the Tumen River Basin. There was high diversity in SFGR species and tick species in the areas surveyed.

6.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-777946

ABSTRACT

Objective To mastered the distribution characteristics of Haemaphysalis longicornis in the Tumen River basin along the border between Russia, Korea and Northeast China, and understand the status of Haemaphysalis longicornis carrying the virus of fever with thrombocytopenia syndrome (SFTS), then, isolate the virus and analyze its genetic characteristics. Method Ticks were collected from Hunchun, Tumen, Helong and Longjing cities in the Tumen River basin of Jilin Province from April to September, 2017. Haemaphysalis longicornis was selected and grouped. SFTS virus was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Virus isolation was carried out in Vero cells, besides, S,M,L gene segments were amplified . The homology of S, M and L gene segments was compared, phylogenetic tree was established, and their gene characteristics were analyzed. Result Haemaphysalis longicornis mainly distributed in Hunchun and Tumen City in the lower reaches of Tumen River. It was the dominant species in the two counties, reaching 71.85% and 87.62% respectively. A virus named YBHC-TICK2-2017/CHINA was isolated from Haemaphysalis longicornis collected in Hunchun. The sequences of S segment (1 746 bp), M segment (3 336 bp) and L segment (6 376 bp) of the virus were 98.00%-99.00%, homologous to those of SFTS virus isolates from China and Korea recorded in National Center for Biotechnology Information (NCBI) Gen Bank. Phylogenetic tree analysis showed that the S segment gene sequence of the virus strain was divided into a cluster with Jilin strain (KT890282) in China, and M segment and L segment gene sequence with Jiangsu strain (KR230781) in China. Conclusions Haemaphysalis longicornis are widely distributed in the lower reaches of the Tumen river. It was the first time that SFTS virus was isolated from Haemaphysalis longicornis in this area, suggesting that this area is important for SFTS prevention.

7.
Diabetes Ther ; 9(6): 2407, 2018 12.
Article in English | MEDLINE | ID: mdl-30293159

ABSTRACT

In the original publication, conclusion was incorrectly updated in the article main text. The complete statement is given below.

8.
Diabetes Ther ; 9(5): 2163-2171, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30220039

ABSTRACT

INTRODUCTION: In this analysis, we aimed to systematically compare percutaneous coronary intervention (PCI) versus coronary artery bypass surgery (CABG) in terms of adverse outcomes utilizing data from a recent (2015-2017) population of patients with type 2 diabetes mellitus (T2DM). METHODS: An electronic search of recent studies (2015-2017) was carried out using 'diabetes mellitus,' 'coronary artery bypass surgery,' and 'percutaneous coronary intervention' as the main search terms. Uncomplicated T2DM patients with stable coronary artery disease (CAD), left main CAD, and multi-vessel disease were included. RevMan software (version 5.3) was used to calculate odds ratios (OR) and 95% confidence intervals (CIs). RESULTS: Among a total of 13,114 T2DM patients, CABG and PCI patients did not differ significantly in their rates of mortality (OR 0.90, 95% CI 0.61-1.31; P = 0.57) and cardiac death (OR 1.00, 95% CI 0.78-1.30; P = 0.98). However, rates of major adverse events, repeat revascularization, and myocardial infarction were significantly higher in the PCI group. Stroke rates did not significantly differ between the two groups. CONCLUSION: Mortality (1-5 years) did not significantly differ between the CABG and PCI patients with T2DM. However, rates of other major adverse events were significantly higher in the PCI patients, suggesting that CABG is more advantageous than PCI in patients with T2DM.

9.
Diabetes Ther ; 9(3): 1269-1277, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29744820

ABSTRACT

INTRODUCTION: Insulin injection is the main treatment in patients with type 1 diabetes mellitus (T1DM). Even though continuous glucose monitoring has significantly improved the conditions of these patients, limitations still exist. To further enhance glucose control in patients with T1DM, an artificial pancreas has been developed. We aimed to systematically compare artificial pancreas with its control group during a 24-h basis in patients with T1DM. METHODS: Electronic databases were carefully searched for English publications comparing artificial pancreas with its control group. Overall daytime and nighttime glucose parameters were considered as the endpoints. Data were evaluated by means of weighted mean differences (WMDs) and 95% confidence intervals (CIs) generated by RevMan 5.3 software. RESULTS: A total number of 354 patients were included. Artificial pancreas significantly maintained a better mean concentration of glucose (WMD - 1.03, 95% CI - 1.32 to - 0.75; P = 0.00001). Time spent in the hypoglycemic phase was also significantly lower (WMD - 1.23, 95% CI - 1.56 to - 0.91; P = 0.00001). Daily insulin requirement also significantly favored artificial pancreas (WMD - 3.43, 95% CI - 4.27 to - 2.59; P = 0.00001). Time spent outside the euglycemic phase and hyperglycemia phase (glucose > 10.0 mmol/L) also significantly favored artificial pancreas. Also, the numbers of hypoglycemic events were not significantly different. CONCLUSION: Artificial pancreas might be considered an effective and safe alternative to be used during a 24-h basis in patients with T1DM.

10.
Diabetes Ther ; 9(2): 753-770, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29524188

ABSTRACT

INTRODUCTION: Empagliflozin is a new, emerging oral hypoglycemic agent (OHA) which has shown significant benefits in type 2 diabetes mellitus (T2DM) patients with cardiovascular disease. In this analysis, our aim was to systematically compare the adverse drug events (ADEs) associated with a low (10 mg) versus a high (25 mg) dose of empagliflozin as (1) monotherapy, (2) as an add-on to other OHAs, and (3) as an add-on specifically to metformin, in patients who were treated for T2DM. METHODS: This was a systematic review and meta-analysis of randomized controlled trials that compared empagliflozin 10 mg versus 25 mg in patients who were treated for T2DM and which reported adverse drug reactions as their clinical endpoints. Statistical analysis was carried out using the latest version of the RevMan software (ver. 5.3) whereby odds ratios (OR) and 95% confidence intervals (CI) were generated. RESULTS: Eight trials with a total number of 8514 patients treated for T2DM were included in this meta-analysis and systematic review, of whom 4261 patients received 10 mg empagliflozin and 4253 patients received 25 mg empagliflozin. Our results showed that there were no significant differences between the patients with T2DM receiving 10 empagliflozin and those receiving 25 mg empagliflozin in terms of drug-related adverse effects (OR 1.06, 95% CI 0.93-1.21; P = 0.40, I2 = 0%), adverse events leading to drug discontinuation (OR 0.99, 95% CI 0.86-1.14; P = 0.87, I2 = 0%), and serious adverse events (OR 1.06, 95% CI 0.95-1.18; P = 0.31, I2 = 0%) when empagliflozin was provided as monotherapy or as an add-on to other anti-diabetic medications. The same results were obtained when empagliflozin was used as an add-on to metformin or as monotherapy. The duration of the follow-up periods did not affect the results. However, the incidence of genital and urinary tract infections (UTIs) was significantly higher in female patients than in male patients with 10 or 25 mg empagliflozin. CONCLUSIONS: The incidence of ADEs was not significantly different in T2DM patients receiving 10 versus 25 mg empagliflozin as monotherapy or as add-on to metformin or other anti-diabetic drugs during a shorter or longer follow-up period. However, genital and UTIs were more common in female patients with T2DM irrespective of empagliflozin dosage.

11.
J Med Syst ; 40(3): 48, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26643078

ABSTRACT

Heart rate is an important clinical measure that is often used in pathological diagnosis and prognosis. Valid detection of irregular heartbeats is crucial in the clinical practice. We propose an artificial neural network using the calculated pulse rate to detect irregular interbeats. The proposed system measures the calculated pulse rate to determine an "irregular interbeat on" or "irregular interbeat off" event. If an irregular interbeat is detected, the proposed system produces a danger warning, which is helpful for clinicians. If a non-irregular interbeat is detected, the proposed system displays the calculated pulse rate. We include a flow chart of the proposed software. In an experiment, we measure the calculated pulse rates and achieve an error percentage of < 3% in 20 participants with a wide age range. When we use the calculated pulse rates to detect irregular interbeats, we find such irregular interbeats in eight participants.


Subject(s)
Arrhythmias, Cardiac/diagnosis , Heart Rate/physiology , Monitoring, Physiologic/instrumentation , Neural Networks, Computer , Signal Processing, Computer-Assisted/instrumentation , Humans , Infrared Rays , Pulse , Software Design
12.
Opt Lett ; 39(15): 4565-7, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-25078229

ABSTRACT

We demonstrate a simple and unique double-Brillouin-frequency spaced multiwavelength structure. It uses the reflection property of an isolator and fiber loop mirror which is made of a 50:50 coupler. This scheme has only one loop, instead of two or more loops, to separate the odd and even Stokes waves generated by Brillouin scattering. The light going into loop cavity can be absorbed twice to produce a Brillouin Stokes wave twice in one round loop, so a double-Brillouin-frequency spaced multiwavelength harmonics wave can be achieved in the output of the structure. Finally, our experiment successfully achieves a double-Brillouin-frequency space of about 0.1475 and 0.1734 nm in two different type structures.

13.
Ying Yong Sheng Tai Xue Bao ; 23(5): 1277-85, 2012 May.
Article in Chinese | MEDLINE | ID: mdl-22919838

ABSTRACT

A total of 79 rice materials containing Dongxiang wild rice (Oryza rufipogon Griff. ) backcross lines (Dwr)/Xie-qingzao B (Xqz B)//Xqz B and their parents were chosen as the test objects to study the relationships between the drought resistance of these materials and the 31 drought resistance indices at germinating stage, seedling stage, booting stage, and mature stage. The results showed that the drought resistance index or the drought resistance coefficient of these materials were significantly correlated to the relative germination energy (RGE) under 15% PEG-6000 drought stress, the germination drought resistance index (GDRI) and relative germination energy (RGE) under 20% PEG-6000 drought stress, and the relative value of maximum root length (MRL), seeding height (SH), fresh root mass (FRM), dry root mass (DRM), root relative water content (RRWC), wilting rate (WR), leaf soluble sugar content (LSSC), leaf proline content (LPC), leaf MDA content (LMDAC), leaf relative water content (LRWC), level of rolling leaf (RL), plant height (PH), tiller number per plant (TNP), productive tiller number per plant (PTNP), filled spikelets per panicle (FSP), panicle density (PD), seed setting rate (SR), and 1000-grain mass (TGM) under water stress. Through stepwise regression analysis, nine drought resistance indices including the RGE under 20% PEG-6000 drought stress and the relative values of DRM, RRWC, LSSC, LPC, LMDAC, ETNP, SR, and TGM under water stress were selected. Base on these indices and their partial correlation coefficients, the drought resistance evaluation equation (D value) and evaluation system were established, which could well assess the drought resistance of the Dongxiang common wild rice backcross lines at different growth stages.


Subject(s)
Adaptation, Physiological , Droughts , Oryza/physiology , China , Oryza/genetics , Plants, Genetically Modified/growth & development , Plants, Genetically Modified/physiology , Seedlings/physiology , Stress, Physiological
14.
J Zhejiang Univ Sci B ; 12(7): 518-26, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21726058

ABSTRACT

Rice straw is always regarded as a by-product of rice production, but it could be a significant energy source for ruminant animals. Knowledge of the genetic variation and genetic architecture of cell wall traits will facilitate rice breeders by improving relevant traits through selective breeding and genetic engineering. The common wild rice, Oryza rufipogon Griff., which is considered to be the progenitor of Oryza sativa, has been widely utilized for the identification of genes of agronomic importance for rice genetic improvement. In the present study, the mapping of quantitative trait loci (QTLs) for acid detergent fiber (ADF), neutral detergent fiber (NDF), acid detergent lignin (ADL), and ADL/NDF ratio was carried out in two environments using a backcrossed inbred line (BIL) population derived from a cross between the recurrent parent Xieqingzao B (XB) and an accession of Dongxiang wild rice (DWR). The results indicated that all four traits tested were continuously distributed among the BILs, but many BILs showed transgressive segregation. A total of 16 QTLs were identified for the four traits, but no QTLs were in common in two environments, suggesting that environment has dramatic effects on fiber and lignin syntheses. Compared to the QTL positions for grain yield-related traits, there were no unfavorable correlations between grain yield components and cell wall traits in this population. The QTLs identified in this study are useful for the development of dual-purpose rice varieties that are high in grain yield and are also high in straw quality.


Subject(s)
Lignin/analysis , Oryza/genetics , Quantitative Trait Loci , Analysis of Variance , Oryza/chemistry , Phenotype
15.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-978296

ABSTRACT

@#ObjectiveTo observe the effect of integrated traditional Chinese medicine therapy on diabetic peripheral neuropathy.Methods22 patients with diabetic peripheral neuropathy were as the group of integrated traditional Chinese medicine therapy ,who received Chinese herbal medicine treatment(orally),acupuncture,etc. Other 20 cases were as the control group,disease natural course. The effect of two groups were compared with the means.ResultsThe patients in group of integrated traditional Chinese medicine therapy got obviously better results than that of the control group(P<0.05).ConclusionThe integrated traditional Chinese medicine therapy is effective on diabetic peripheral neuropathy.

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