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1.
Sensors (Basel) ; 17(2)2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28212291

RESUMO

Tracking the target that maneuvers at a variable turn rate is a challenging problem. The traditional solution for this problem is the use of the switching multiple models technique, which includes several dynamic models with different turn rates for matching the motion mode of the target at each point in time. However, the actual motion mode of a target at any time may be different from all of the dynamic models, because these models are usually limited. To address this problem, we establish a formula for estimating the turn rate of a maneuvering target. By applying the estimation method of the turn rate to the multi-target Bayes (MB) filter, we develop a MB filter with an adaptive estimation of the turn rate, in order to track multiple maneuvering targets. Simulation results indicate that the MB filter with an adaptive estimation of the turn rate, is better than the existing filter at tracking the target that maneuvers at a variable turn rate.

2.
Zhonghua Yi Xue Za Zhi ; 93(11): 845-8, 2013 Mar 19.
Artigo em Chinês | MEDLINE | ID: mdl-23859392

RESUMO

OBJECTIVE: To evaluate the effects of relieving pains and restoring vertebral heights of percutaneous balloon kyphoplasty by extra-pedicular approach as a minimally invasive treatment in patients with painful osteoporotic vertebral compressive fractures (OVCF). METHODS: A retrospective analysis was conducted for 96 consecutive patients. There were 64 females and 32 males with a mean age 67 years (range: 55 - 82). Symptomatic levels were identified by correlating their clinical presentations with the findings of magnetic resonance imaging (MRI). The interval between onset of symptoms and surgical intervention ranged from 2 days to 4 months. A total of 118 levels (56 thoracic, 62 lumbar) were treated in this cohort. Immediate and postoperative 3-month follow-up visits were conducted. Visual analog scale (VAS) pain scores, preoperative and postoperative anterior, midline vertebral heights for fractured vertebrae were measured on lateral radiographs to evaluate the procedural outcomes. RESULTS: There was swift pain relief associated with evident augmentation in weight-bearing resistance. Pain decreased from 8.1 to 2.1 points. Through kyphoplasty, the anterior, midline vertebral heights of 118 fractured vertebral bodies increased up to (75.83 ± 19.84)% and (71.23 ± 21.45)% respectively. None of them had worsening of fracture-induced narrowing of spinal canal. No device-related major complications occurred. CONCLUSION: Percutaneous kyphoplasty through an extra-pedicular approach results in immediate clinical improvement of mobility and pain relief. It safely increases vertebral body height and quickly returns geriatric patients to higher activity levels, increased independence and better quality-of-life. And its short-term outcomes are excellent.


Assuntos
Fraturas por Compressão/cirurgia , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas por Compressão/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas da Coluna Vertebral/etiologia , Resultado do Tratamento
3.
Zhonghua Yi Xue Za Zhi ; 92(9): 620-3, 2012 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-22800952

RESUMO

OBJECTIVE: To assess the clinical and radiographic outcomes of posterior lumbar fixation and posterior interbody fusion or improved transforaminal lumbar interbody fusion for Meyerding grade II/III spondylolisthesis so as to address the suitability of a dynamic stabilization. METHODS: A total of 28 consecutive patients underwent posterior lumbar fixation and posterior interbody fusion or improved transforaminal lumbar interbody fusion for Meyerding grade II/III spondylolisthesis. Among them, 13 patients underwent posterior interface fusion (PLIF) and pedicle screw fixation. And improved transforaminal lumbar interbody fusion (ITLIF) and placement of the same system were performed in 15 patients. Their clinical, economic, functional, and radiographic data were recorded both pre- and postoperatively. RESULTS: The average changes of economic and functional scores on the Prolo scale were 1.36 and 1.48 respectively. In patients with posterior interbody fusion; the average preoperative vertebral slippage was 46.9% (range: 25 - 75%) versus 14.6% (range: 15 - 25%) postoperatively. In patients with ITLIF, the average changes in economic and functional scores were 1.75 and 1.63 respectively. And the average preoperative vertebral slippage was 45.2% (range: 28 - 78%) compared with 26.3% (range: 14 - 28%) postoperatively. When two fusion techniques were compared, an overall superior reliability and resistance of systems was associated with the ITLIF procedure. But their clinical outcomes did not differ greatly (P > 0.05). CONCLUSIONS: The application of a segmental pedicle screw fixation is both feasible and efficacious.


Assuntos
Estenose Espinal/cirurgia , Espondilolistese/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Fixadores Internos , Vértebras Lombares , Pessoa de Meia-Idade , Fusão Vertebral/métodos , Estenose Espinal/complicações , Espondilolistese/complicações , Resultado do Tratamento
4.
Zhongguo Gu Shang ; 25(11): 928-30, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23427594

RESUMO

OBJECTIVE: To study surgical treatment for the deep wound infections after the operation of posterior lumbar interlumbar fusion (PLIF) in lumbar spinal stenosis. METHODS: From December 2005 to December 2010,10 patients with the deep wound infection of the PLIF were analyzed retrospectively, including 4 males and 6 females, with a mean age of 52.8 years (ranged from 34 to 70 years). All the patients were treated with debridement and the drainage. The sensitive antibiotics were used. The VAS score, erythrocyte sedimentation rate (ESR), C reactive protein (CRP), and JOA lumbar score were used to compare the clinical results pre-and post-operation. RESULTS: All the patients were followed up, and the mean duration was 24 months (ranged from 19 to 28 months). One patient developed to an intervertebral space infection and the cage was removed. One patient suffered a radical central nerve system infection and died after the debridement. Other 8 patients got a good clinical result. The VAS score decreased from preoperative 8.0 +/- 0.4 to postoperative 2.8 +/- 0.3; JOA score improved from preoperative 10.30 +/- 3.02 to postoperative 24.10 +/- 2.85; ESR decreased from preoperative (85.0 +/- 17.0) mm/h to postoperative (14.0 +/- 6.0) mm/h; both CRP and WBC decreased from preoperative (73.5 +/- 14.3) mg/L, (11.1 +/- 1.8) x 10(9)/L to postoperative (5.1 +/- 1.1) mg/L, (7.4 +/- 0.5) x 10(9)/L respectively. CONCLUSION: Treatment of patients with deep wound infections after PLIF with debridement, drainage, and sensitive antibiotics could get a good long-term clinical result, which is important to treat the patients with high-risk factors. Early diagnosis and operation is the key to deal with the patients with deep wound infections after PLIF.


Assuntos
Vértebras Lombares/cirurgia , Fusão Vertebral/efeitos adversos , Estenose Espinal/cirurgia , Infecção da Ferida Cirúrgica/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Zhongguo Gu Shang ; 25(12): 975-8, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23627140

RESUMO

OBJECTIVE: To analyze the advantages and disadvantages of bipedicular approach and uni-extrapedicular approach of vertebroplasty in treating osteoporotic vertebral compression fractures (OVCFs). METHODS: From January 2008 to December 2010,53 patients with OVCFs were retrospectively analyzed. There were 24 males, 30 females with an average age of 66.9 years (ranged,59 to 88 years). Among them, 26 cases were treated with bipedicular approach, 28 cases were treated with uni-extrapedicular approach. The data of bone cement injection, radiology exposure times, operation time, bone cement leakage and vessels nerve complications were observed. Cobb angle, vertebral compression ration were observed by imaging data, and evaluate recovery of deformity. RESULTS: The data of bone cement injection, radiology exposure times, operation time, VAS score were (6.6 +/- 0.8) ml and (6.8 +/- 1.5) ml, (21.7 +/- 4.0) times and (17.9 +/- 3.6) times, (40.5 +/- 5.5) min and (31.6 +/- 9.1) min, (2.8 +/- 0.6) scores and (3.1 +/- 0.5) scores respectively. Cobb angle,vertebral compression ration were (7.6 +/- 2.0) degrees and (6.9 +/- 2.6) degrees, (18.1 +/- 5.8)% and (16.5 +/- 6.1)%. There were no vascular nerve complications occurred. For bone cement leakage, 3 cases (11%) in bipedicular approach and 3 cases (11%)in uni-extrapedicular approach. There was no significant differences between two groups in VAS score, recovery of vetebral body, Cobb angle, bone cement injection and bone cement leakage, but had significant differences in radiology exposure times and operation time (P<0.05). CONCLUSION: Both of two approaches can treat OVCFs well, especially extropedicle approach which could reduce operation time and radiation shoot frequency.


Assuntos
Fraturas por Compressão/cirurgia , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
6.
Zhonghua Yi Xue Za Zhi ; 91(43): 3062-5, 2011 Nov 22.
Artigo em Chinês | MEDLINE | ID: mdl-22333060

RESUMO

OBJECTIVE: To evaluate the clinical efficacies, indications and application values of posterior fusion plus pedicle screw fixation in the treatment of upper cervical spine instability. METHODS: From May 2006 to December 2010, a total of 24 patients with atlantoaxial instability were treated with C1-2 pedicle screws and rod fixation under general anesthesia. There were 18 males and 6 females with a mean age of 49.8 years old (range: 17 - 69). RESULTS: The postoperative radiographs verified a good position of all screws with satisfactory atlantoaxial reduction. A mean follow-up period of 23 months (range: 3 - 45) showed no injury of spinal cord and vertebral artery or inter fixation failure. Atlantoaxial alignment and stability were restored without instrumentation-related complications. CONCLUSION: Posterior atlantoaxial pedicle screw and rod fixation provide immediate three-dimensional rigid fixation of atlantoaxial joint. It is a more effective technique than with previously reported techniques.


Assuntos
Articulação Atlantoaxial/cirurgia , Vértebras Cervicais , Fixação Interna de Fraturas/métodos , Instabilidade Articular/cirurgia , Adolescente , Adulto , Idoso , Parafusos Ósseos , Feminino , Humanos , Fixadores Internos , Masculino , Pessoa de Meia-Idade , Fusão Vertebral/métodos , Resultado do Tratamento , Adulto Jovem
7.
Bull Environ Contam Toxicol ; 84(5): 513-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20414640

RESUMO

Based on the acid rain and concurrent meteorological observational data during the past 10 years in Fujian Province, China, the dependence of distribution characteristics of acid rain on season, rain rate, weather pattern and dominant airflow in four regions of Fujian Province is analyzed. On the annual average, the acid rain frequency is the highest (above 40%) in the southern and mid-eastern regions, and the lowest (16.2%) in the western region. The acid rain occurs most frequently in spring and winter, and least frequent in summer. The acid rain frequency in general increases with the increase of precipitation. It also depend on the direction of dominant airflows at 850 hPa. In the mid-eastern region, more than 40% acid rains appear when the dominant wind directions are NW, W, SW, S and SE. In the southern region, high acid rain occurrence happens when the dominant wind directions are NW, W, SW and S. In the northern region, 41.8% acid rains occur when the southwesterly is pronounced. In the western region, the southwesterly is associated with a 17% acid rain rate. The examination of meteorological sounding conditions over Fuzhou, Xiamen and Shaowu cities shows that the acid rain frequency increases with increased inversion thickness. Based on the results above, a meteorological potential forecast model for acid rain is established and tested in 2007. The result is encouraging. The model provides an objective basis for the development of acid rain forecasting operation in the province.


Assuntos
Chuva Ácida/análise , Poluentes Ambientais/análise , Previsões , Conceitos Meteorológicos , Modelos Teóricos , China , Monitoramento Ambiental , Estações do Ano
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(7): 1530-4, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18844155

RESUMO

To solve the problems of real-time online measurement for the freezing point of diesel fuel products, a soft sensing method by near-infrared (NIR) spectrometry was proposed. Firstly, the information of diesel fuel samples in the spectral region of 750-1 550 nm was extracted by spectrum analyzer, and the polynomial convolution algorithm was also applied in spectrogram smoothness, baseline correction and standardization. Principal component analysis (PCA) was then used to extract the features of NIR spectrum data sets, which not only reduced the number of input dimension, but increased their sensitivity to output. Finally the soft sensing model for freezing point was built using SVR algorithm. One hundred fifty diesel fuel samples were used as experimental materials, 100 of which were used as training (calibrating) samples and the others as testing samples. Four hundred and one dimensional original NIR absorption spectrum data sets, through PCA, were reduced to 6 dimensions. To investigate the measuring effect, the freezing points of the testing samples were estimated by four different soft sensing models, BP, SVR, PCA-BP and PCA+SVR. Experimental results show that (1) the soft sensing models using PCA to extract features are generally better than those used directly in spectrum wavelength domain; (2) SVR based model outperforms its main competitors-BP model in the limited training data, the error of which is only half of the latter; (3) The MSE between the estimated values by the presented method and the standard chemical values of freezing point by condensing method are less than 4.2. The research suggests that the proposed method can be used in fast measurement of the freezing point of diesel fuel products by NIRS.

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