C&I(chopping and interleaving)干扰是一种针对线性调频(linear frequency modulation,LFM)雷达的典型干扰样式,干扰子信号调频斜率与雷达发射信号相同,利用信号处理工具分离真实回波与干扰信号难度较大。针对该问题,以LFM相参雷...C&I(chopping and interleaving)干扰是一种针对线性调频(linear frequency modulation,LFM)雷达的典型干扰样式,干扰子信号调频斜率与雷达发射信号相同,利用信号处理工具分离真实回波与干扰信号难度较大。针对该问题,以LFM相参雷达抗自卫式C&I干扰为背景,提出基于回波预处理和相参积累的干扰抑制算法。根据估计的回波时延,设置距离窗截取受干扰回波段,在此基础上,通过对回波预处理,改变不同重复周期内假目标的快时间位置分布,通过相参积累实现干扰抑制。仿真试验表明,所提算法能够有效抑制强干扰背景下的C&I干扰,干扰抑制后真实目标检测概率大幅提高,虚假目标数量明显减少。展开更多
频谱弥散(smeared spectrum,SMSP)干扰和切片组合(chopping and interleaving,C&I)干扰是两种用于对抗线性调频(linear frequency modulation,LFM)脉冲压缩雷达的干扰样式。相比SMSP干扰,C&I干扰与雷达发射信号相似度更高,干扰...频谱弥散(smeared spectrum,SMSP)干扰和切片组合(chopping and interleaving,C&I)干扰是两种用于对抗线性调频(linear frequency modulation,LFM)脉冲压缩雷达的干扰样式。相比SMSP干扰,C&I干扰与雷达发射信号相似度更高,干扰抑制更为困难。针对该问题,以远距离支援干扰下LFM相参雷达对抗C&I干扰为背景,提出快慢时间域联合处理C&I干扰抑制算法。分析了C&I干扰时频特征和对相参雷达的干扰特性,在此基础上,通过快慢时间域处理估计干扰位置、幅度、多普勒频率、采样周期、采样脉宽等参数,重构干扰信号,通过对消实现干扰抑制。仿真试验验证了所提算法的可行性和有效性。展开更多
This work was a retrospective prospective study carried out in the general surgery department of the Cs ref of commune I from January 2009 to December 2012. Our study aimed to determine the hospital frequency of hemor...This work was a retrospective prospective study carried out in the general surgery department of the Cs ref of commune I from January 2009 to December 2012. Our study aimed to determine the hospital frequency of hemorrhoidal disease, to identify the contributing factors, describe the clinical and therapeutic aspects and analyze the surgical consequences. We collected 73 patients with an average age of 37.8 years (range: 19 years and 77 years) with a sex ratio of 2.5 in favor of men. We operated on 49 patients or 67.1% of cases. 71.2% of our patients were married and lived in Bamako. Schoolchildren and middle managers made up 39.8% of cases. 82.2% of patients were seen in ordinary consultation and 69.9% complained of progressive anal pain in 66.7% of cases. This pain was triggered by defecation in 88.2% of our patients. The contributing factors were dominated by constipation (53.4%), working in a seated position (41.1%) and a sedentary lifestyle (16.4%) of cases. Stage IV external hemorrhoids and hemorrhoidal thrombosis represented 53.8% of surgical indications. The most used surgical technique was that of Milligan-Morgan, i.e. 51.9% of cases and 45.2% of patients treated medically received a combination of transit regulator, venotonics and analgesics. The surgical aftermath was marked by hemorrhage (3 cases), delayed healing (5 cases), urinary retention (1 case) and scarring anal stenosis (1 case). The morbidity rate was 5.48% of cases and a zero mortality rate. The average length of hospitalization was 2 days with extremes of 1 and 5 days.展开更多
Inguinal hernia in children is a congenital pathology in children linked to the persistence of the peritoneo-vaginal canal in children and the NüCK canal in girls;persisting into adulthood. This work aimed to stu...Inguinal hernia in children is a congenital pathology in children linked to the persistence of the peritoneo-vaginal canal in children and the NüCK canal in girls;persisting into adulthood. This work aimed to study inguinal hernia in children in the general surgery department of the Reference Health Center of Commune I of the Bamako District;to determine the frequency of inguinal hernia;describe the epidemiological, clinical and therapeutic aspects of inguinal hernias and in order to evaluate the cost of treatment. This was a prospective study from April 2017 to March 2018 during which 60 children with an inguinal hernia were collected. Inguinal hernias in children represented 9.23% of patients operated on in the department. The average age was 59.23 months with extremes of one month and 180 months and a standard deviation of 49.23 years. The male sex was dominant with a sex ratio equal to 9:1. The notion of prematurity was found in 11.7% and was associated with a testicle not in place in 1.7% of cases. 41.7% of our patients were referred by a doctor and 66.7% of patients presented with painless, intermittent inguino-scrotal swelling (83.3% of cases). The hernia was discovered before one week of life in 50% of cases. Inguinal swelling was absent in 11.7% but observed intraoperatively. The inguinal hernia was unilateral in 91.7% of cases and 70% of hernias were discovered by the parents during pushing efforts. The inguinal hernia was located on the right in 61.7% of cases. The hernia swelling was soft, painless, impulsive and reducible in 78.3% of cases. The swelling was inguino-scrotal in 58.3% of cases. The hernia was simple in 95% of patients and hernial strangulation was observed in 3 cases or 5% of cases. 98.3% of patients were ASA I. The treatment was carried out openly in all our patients including closure of the vaginal peritoneal canal in 95% of cases under general anesthesia in 98.3% of cases. The morbidity rate was 8.4% (surgical site infection: 6.7% of cases and hematoma: 1.7%). The immediate consequences were simple in 96.6% of cases. No cases of recurrence occurred during the 6 months after the intervention. The average cost of care was estimated at 69,743 FCFA.展开更多
文摘C&I(chopping and interleaving)干扰是一种针对线性调频(linear frequency modulation,LFM)雷达的典型干扰样式,干扰子信号调频斜率与雷达发射信号相同,利用信号处理工具分离真实回波与干扰信号难度较大。针对该问题,以LFM相参雷达抗自卫式C&I干扰为背景,提出基于回波预处理和相参积累的干扰抑制算法。根据估计的回波时延,设置距离窗截取受干扰回波段,在此基础上,通过对回波预处理,改变不同重复周期内假目标的快时间位置分布,通过相参积累实现干扰抑制。仿真试验表明,所提算法能够有效抑制强干扰背景下的C&I干扰,干扰抑制后真实目标检测概率大幅提高,虚假目标数量明显减少。
文摘频谱弥散(smeared spectrum,SMSP)干扰和切片组合(chopping and interleaving,C&I)干扰是两种用于对抗线性调频(linear frequency modulation,LFM)脉冲压缩雷达的干扰样式。相比SMSP干扰,C&I干扰与雷达发射信号相似度更高,干扰抑制更为困难。针对该问题,以远距离支援干扰下LFM相参雷达对抗C&I干扰为背景,提出快慢时间域联合处理C&I干扰抑制算法。分析了C&I干扰时频特征和对相参雷达的干扰特性,在此基础上,通过快慢时间域处理估计干扰位置、幅度、多普勒频率、采样周期、采样脉宽等参数,重构干扰信号,通过对消实现干扰抑制。仿真试验验证了所提算法的可行性和有效性。
文摘This work was a retrospective prospective study carried out in the general surgery department of the Cs ref of commune I from January 2009 to December 2012. Our study aimed to determine the hospital frequency of hemorrhoidal disease, to identify the contributing factors, describe the clinical and therapeutic aspects and analyze the surgical consequences. We collected 73 patients with an average age of 37.8 years (range: 19 years and 77 years) with a sex ratio of 2.5 in favor of men. We operated on 49 patients or 67.1% of cases. 71.2% of our patients were married and lived in Bamako. Schoolchildren and middle managers made up 39.8% of cases. 82.2% of patients were seen in ordinary consultation and 69.9% complained of progressive anal pain in 66.7% of cases. This pain was triggered by defecation in 88.2% of our patients. The contributing factors were dominated by constipation (53.4%), working in a seated position (41.1%) and a sedentary lifestyle (16.4%) of cases. Stage IV external hemorrhoids and hemorrhoidal thrombosis represented 53.8% of surgical indications. The most used surgical technique was that of Milligan-Morgan, i.e. 51.9% of cases and 45.2% of patients treated medically received a combination of transit regulator, venotonics and analgesics. The surgical aftermath was marked by hemorrhage (3 cases), delayed healing (5 cases), urinary retention (1 case) and scarring anal stenosis (1 case). The morbidity rate was 5.48% of cases and a zero mortality rate. The average length of hospitalization was 2 days with extremes of 1 and 5 days.
文摘Inguinal hernia in children is a congenital pathology in children linked to the persistence of the peritoneo-vaginal canal in children and the NüCK canal in girls;persisting into adulthood. This work aimed to study inguinal hernia in children in the general surgery department of the Reference Health Center of Commune I of the Bamako District;to determine the frequency of inguinal hernia;describe the epidemiological, clinical and therapeutic aspects of inguinal hernias and in order to evaluate the cost of treatment. This was a prospective study from April 2017 to March 2018 during which 60 children with an inguinal hernia were collected. Inguinal hernias in children represented 9.23% of patients operated on in the department. The average age was 59.23 months with extremes of one month and 180 months and a standard deviation of 49.23 years. The male sex was dominant with a sex ratio equal to 9:1. The notion of prematurity was found in 11.7% and was associated with a testicle not in place in 1.7% of cases. 41.7% of our patients were referred by a doctor and 66.7% of patients presented with painless, intermittent inguino-scrotal swelling (83.3% of cases). The hernia was discovered before one week of life in 50% of cases. Inguinal swelling was absent in 11.7% but observed intraoperatively. The inguinal hernia was unilateral in 91.7% of cases and 70% of hernias were discovered by the parents during pushing efforts. The inguinal hernia was located on the right in 61.7% of cases. The hernia swelling was soft, painless, impulsive and reducible in 78.3% of cases. The swelling was inguino-scrotal in 58.3% of cases. The hernia was simple in 95% of patients and hernial strangulation was observed in 3 cases or 5% of cases. 98.3% of patients were ASA I. The treatment was carried out openly in all our patients including closure of the vaginal peritoneal canal in 95% of cases under general anesthesia in 98.3% of cases. The morbidity rate was 8.4% (surgical site infection: 6.7% of cases and hematoma: 1.7%). The immediate consequences were simple in 96.6% of cases. No cases of recurrence occurred during the 6 months after the intervention. The average cost of care was estimated at 69,743 FCFA.