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Communications and Network 2022年第3期14卷 91-107页

作者： Abdelrahman El Gebali René Jr landry Lassena Laboratory Department of Electrical Engineering &#201cole de Technologie Supérieure (&#201TS) Montreal Canada

A jamming signal such as single and multiple Continuous-Wave (CW and MCW) interferences have been shown to have severe effects on the quality of the received signal in wireless communication. This paper presents an approach of a low-complexity algorithm that compares the performances of using Adaptive Notch Filter (ANF) direct and lattice forms structures based on second-order Infinite Impulse Response (IIR) Notch Filter (NF) for the detection and mitigation of CW and MCW interferences in QPSK communication systems. The approach method consists of two ANFs, adaptive IIR NF and adaptive IIR NF . The present algorithm can estimate and mitigate each CWI and computer their power in Time-Domain (TD). In results for performance comparison, the lattice IIR NF structure outperforms the direct IIR NF structure for detection and removal jamming and has a better Bit Error Ratio (BER). Furthermore, compared with the case of full suppression (), both cases (direct and lattice form) work better for low and high-power jammers. Also, compared to the case without an IIR NF, the presented algorithm can detect and mitigate, track hopping frequency interference, and improve BER performance.

关键词： CWI MCWI ANF BER IIR QPSK Direct and Lattice Form and JSR

Thermal characterization of bio-based phase changing materials in decorative wood-based panels for thermal energy storage

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Green Energy & Environment 2019年第1期4卷 56-65页

作者： Damien Mathis Pierre Blanchet Véronic landry Philippe Lagière NSERC Industrial Research Chair on Ecoresponsible Wood Construction(CIRCERB) Laval University Engineering and Mechanics Institute University of Bordeaux Avenue D'Aquitaine

Decorative wood panels containing pouches of bio-based phase changing materials(PCMs) were prepared. Three different PCM mixtures were used: a blend of capric and lauric acids as well as two commercial products, Puretemp?20 and Puretemp?23(Puretemp). The panels consist of engraved Medium Density Fiberboard(MDF) filled with a plastic pouch filled with PCM. High density fiberboard(HDF) was used on top of the panels to enclose the PCM pouches. PCM mixtures were first tested by differential scanning calorimetry(DSC). Phase change temperature and total heat storage of the panels were measured for both fusion and solidification with a Dynamic Heat-Flow Meter Apparatus(DHFMA). DSC and DHFMA results were compared, allowing a better understanding of results gathered from these two techniques. DSC calibration has been revealed important when assessing PCMs. The panels present a phase change temperature and a latent heat storage suitable for buildings applications. The panel made with Puretemp?23 presented the highest energy, with 57.1 J g^(-1). Thermal cycling was conducted on the panels to investigate thermal reliability, which revealed small modifications of thermal properties for two products. For all cases, latent heat was found stable. Hygro-mechanical behavior of the panels was also evaluated as these where designed to be esthetic decorative panels. This study exposes the potential of a new type of wood-based panels loaded with PCM for thermal energy storage and brings overall knowledge about PCM products thermal characterization.

关键词： PCM Wood Biosourced Fatty acids DHFMA

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人声情感分析

人声情感分析

作者： Dejoli Tientcheu Touko landry 华南理工大学

学位级别：硕士

情感分析技术应用已被在智能电子设备、医疗保健系统和其他几个领域得到应用。语音情感分析是指使用各种技术发现和分析语音数据中存在的潜在情感,重点关注人声的语音和非语音部分。语音情感识别的两个主要挑战是:第一,数据稀缺,可靠数... 详细信息

情感分析技术应用已被在智能电子设备、医疗保健系统和其他几个领域得到应用。语音情感分析是指使用各种技术发现和分析语音数据中存在的潜在情感,重点关注人声的语音和非语音部分。语音情感识别的两个主要挑战是:第一,数据稀缺,可靠数据集的数量有限。第二个问题是,混合情感出现在人声信号,例如,人们可能感知到混合信息,表达一种情感的语音和表达完全不同事物的非言语声音线索。这些差异促使我们研究使用鲁棒识别系统框架。最近,深度学习算法已成功地应用于语音情感识别(SER),各种模型结构显示出提取高级情感特征表示的良好能力,并在现有数据集上取得了良好的准确性。然而,当这些系统在现实中被应用时,精度会大幅下降。其中一个原因是,大多数关于人类情感识别系统的研究都是在安静的场景和环境中记录,是有请演员来扮演,是脚本数据集类型,其中背景噪声几乎不存在,一段音频尽量突出单个情感。性能下降的另一个原因是,在现有模型中没有考虑到自然人类交流过程中出现的包含有价值情感信息的情感声音和声音突发。本文的主要的工作需要将语音情感和非语音人声情感识别处理统一到一个框架中,即考虑了非语音人声情感识别与传统语音情感识别的高度关联性,有考虑到其特殊性为双过程情感分析方案提供合理性分析;本文的情感分析的研之涉及到语气(没有考虑词)通过分析音频样本数据的声学和频谱特征来优化人声情感识别。采取的步骤如下:1、构建了一个多语言数据集ASVP-ESD(音频、语音和视觉处理实验室-情感声音数据库),其中包括12635个音频样本,其中包含13种不同情感类别的语音(5090)和非语音(7545)情感声音。2、设计了一种基于语音/非语音鉴别的双过程情感识别;第一阶段采用线性回归算法是实现语音和非语音的分类,第二阶段将采用密集卷积网络结构与递归网络相结合的方法,分别提取局部和全局特征、时间相关特征,然后通过简单的logistic回归注意机制检测不同情绪之间的不同特征模式实现情感识别;考虑到人类除了使用包含情感状态的声学和词汇(词)信息的言语情态外,还可以使用非言语声音来表达情感;这两个阶段的识别可以有效地建立情感语音和非言语声音中表达的情感语音相关性(如:笑声代表快乐)。3、分析了该模型在现有和可用的基于公共语音的数据集上的性能。实施说话人无关实验后获得的结果表明,上述提出的模型架构在会话类型数据集(如具有4种不同情绪的IEMOCAP)上实现了与最新发布的结果相同的结果,并在单说话人数据集上实现了合理的结果。在使用两阶段识别策略,该模型在使用13种不同情绪的ASVP-ESD数据集上实现时达到了令人满意的精度,在测试集上超过了传统的单阶段方法2%的加权精度(WA)。

关键词：语音情感识别语音和非语音情感声音密集连接神经网络递归神经网络注意机制

植物体系非生物纳米载体的开发及生物分子递送应用

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植物体系非生物纳米载体的开发及生物分子递送应用

Laparoscopic Radical Cystectomy in a Low-Middle Income Country: A 5-Year Review of a Single Institution;Operative Data, Oncologic Results and Morbidity

首届植物科学前沿学术大会

作者：张欢 Natalie Goh Markita landry 暨南大学化学与材料学院 University of California-Berkeley

植物基因工程是农业科技革命的关键技术,发展高效、安全的遗传转化技术是基因工程和遗传育种等领域的研究热点之一。传统的遗传转化技术(农杆菌转化法和基因枪法)存在物种受限、基因整合、组织损伤及效率低等问题,不能满足日益增长的植... 详细信息

植物基因工程是农业科技革命的关键技术,发展高效、安全的遗传转化技术是基因工程和遗传育种等领域的研究热点之一。传统的遗传转化技术(农杆菌转化法和基因枪法)存在物种受限、基因整合、组织损伤及效率低等问题,不能满足日益增长的植物遗传转化需求。本系列研究充分发挥DNA纳米技术的高度可设计性及可编程性,设计开发了DNA纳米结构以及纳米金等纳米载体,通过精确地调控纳米载体的物理化学性质,如尺寸、刚性等,系统的研究了纳米载体被植物细胞有效摄取的性能参数。结果标明,DNA纳米结构的尺寸及刚性是决定其是否可以有效摄取的两个关键指标。DNA纳米结构作为载体可以有效地将干扰小RNA(siRNA)递送到烟草植物叶片中发挥基因沉默功能,并且沉默效率和相对摄取量成正比。在此研究基础上,我们设计了不同尺寸(5-20 nm)和形状(球形和棒状)的核酸分子修饰的金纳米颗粒,进一步的系统研究纳米颗粒在植物叶片及细胞中的转运及摄取机理。研究结果发现,金纳米颗粒均可以被输送至细胞壁部位,和细胞壁发生一定的相互作用,但是只有棒状的金纳米颗粒可以被植物细胞摄取。进一步使用金纳米颗粒作为载体载带siRNA的结果却标明,10 nm的球形金纳米颗粒具有最优的基因沉默效率。基于此,本研究提出siRNA的载带并不需要纳米载体进入植物细胞,只要载体可以有效地保护siRNA且将其运送至植物细胞壁处,siRNA便可进入细胞发挥基因沉默作用。本系列研究为非生物纳米载体的设计及开发提供了理论指导,有望针对不同的功能生物分子开发定制的纳米载体,更好的服务基于基因编辑的新一代育种技术。

关键词：纳米载体基因沉默生物分子递送植物

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Open Journal of Urology 2023年第11期13卷 484-494页

作者： Axel Stéphane Nwaha Makon landry Oriol Mbouche landry Tchuenkam Laure Kamkui Dadje Marcella Derboise Biyouma Bertin Nginkeu Njinou Pierre Joseph Fouda Maurice Aurelien Sosso Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroon Urology Unit Department of Surgery Douala Laquintinie Hospital Douala Cameroon Department of Surgery Yaounde Gynaeco-Obstetric and Pediatric Hospital Yaounde Cameroon Bali Medical and Surgical Center of Urology (BMSCU) Douala Cameroon Yaounde Central Hospital Yaounde Cameroon

Introduction and Objective: Laparoscopic radical cystectomy (LRC) is an alternative to open approach with lower morbidity and better oncologic outcome. We aim to share our experience on laparoscopic radical cystectomy and to evaluate our morbidity and oncological outcome in our settings. Methodology: An observational study in the Douala Medico-Surgical Urology Centre on 5 patients who underwent laparoscopic cystectomy with or without lymph node dissection and external urine diversion between April 2014 to July 2016 was conducted. The overall survival rate was subsequently estimated. Results: Four men and one woman underwent laparoscopic radical cystectomy during the 5-year study period with a mean age of 54.5-year-old. Three patients were submitted to ileal conduits, one to neobladders, and one patient to uretero-cutaneostomies. The mean operative time was 300 ± 17 minutes and the mean length of hospital stay was 9 ± 3 days. Three patients had minor complications according to Clavien and Dindon Classification treated conservatively without need for further operation. Four patients had transitional cell carcinoma and one Squamous cell carcinoma types. Everyone had negative resection margin while only two had negative lymph node. The median survival years in our study was 2.5 years, the overall survival rates at 2 years were 60%, 40% at 3 years and 20 at 5years. 2 patients die after one year due to renal failure and intercurrent disease. Conclusion: Laparoscopic radical cystectomy carried lower morbidity and cancerological outcome compare to open surgery making it a good alternative for bladder oncologic surgery.

关键词： Radical Cystectomy Laparoscopy Oncology Findings Bladder Cancer

A Meta-Learning Approach for Aircraft Trajectory Prediction

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Communications and Network 2023年第2期15卷 43-64页

作者： Syed Ibtehaj Raza Rizvi Jamal Habibi Markani René Jr. landry É cole de technologies supérieure (&#201TS) Montréal Canada

The aviation industry has seen significant advancements in safety procedures over the past few decades, resulting in a steady decline in aviation deaths worldwide. However, the safety standards in General Aviation (GA) are still lower compared to those in commercial aviation. With the anticipated growth in air travel, there is an imminent need to improve operational safety in GA. One way to improve aircraft and operational safety is through trajectory prediction. Trajectory prediction plays a key role in optimizing air traffic control and improving overall flight safety. This paper proposes a meta-learning approach to predict short- to mid-term trajectories of aircraft using historical real flight data collected from multiple GA aircraft. The proposed solution brings together multiple models to improve prediction accuracy. In this paper, we are combining two models, Random Forest Regression (RFR) and Long Short-term Memory (LSTM), using k-Nearest Neighbors (k-NN), to output the final prediction based on the combined output of the individual models. This approach gives our model an edge over single-model predictions. We present the results of our meta-learner and evaluate its performance against individual models using the Mean Absolute Error (MAE), Absolute Altitude Error (AAE), and Root Mean Squared Error (RMSE) evaluation metrics. The proposed methodology for aircraft trajectory forecasting is discussed in detail, accompanied by a literature review and an overview of the data preprocessing techniques used. The results demonstrate that the proposed meta-learner outperforms individual models in terms of accuracy, providing a more robust and proactive approach to improve operational safety in GA.

关键词： Trajectory Prediction General Aviation Safety Meta-Learning Random Forest Regression Long Short-Term Memory Short to Mid-Term Trajectory Prediction Operational Safety

Persistent interstitial pregnancy diagnosed after two unsuccessful attempts of clandestine abortion: A case report and literature review

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Gynecology and Obstetrics Clinical Medicine 2022年第3期2卷 153-156页

作者： landry W.Tchuenkam Anicet FN.NGate Joel Noutakdie Tochie Fetsus T.Wirwah Flobert Titcheu Axel S.Nwaha Makon Faculty of Medicine and Biomedical Sciences University of Yaounde ICameroon Njombe Saint Jean de Malte Hospital Cameroon

Dear editor,Ectopic pregnancy is a medico-surgical emergency requiring prompt diagnostic and therapeutic *** is defined as the implantation of the embryo outside its normal site within the endometrial cavity.1 The fallopian tube is the most common site of ectopic implantations(96%),followed by the ovary(1%),caesarean section scar(1%–3%),cervix(1%)and viscera of the abdominal cavity(1%).2 Among tubal locations,the interstitium is the least described implantation site(2.6%),whereas the ampulla,isthmus and fimbriated infundibulum have the following respective frequencies:73.3%,12.5%and 11.6%.3 Heterotopic pregnancies are extremely rare cases.

关键词： pregnancy implantation cavity

Hormone-Naïve Metastatic Prostate Cancer: A Presentation of 110 Cases in a Urology Center in the City of Douala, Cameroon

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Open Journal of Urology 2022年第1期12卷 83-97页

作者： Cyril Kamadjou Calson Ambomatei landry Mbouche Zacharie Sando Achille Mbassi Fru Angwafor Medical Surgical Center of Urology and Minimal Invasive Surgery Douala Cameroon Department of Surgery and Specialities Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Health Search Association Douala Cameroon Gyneco-Obstetric and Pediatric Hospital Yaounde Cameroon Urology Service Central Hospital Yaounde Cameroon

Aim: According to World Health Organization, prostate cancer is one of the increasing malignancies in men worldwide. This paper aims to describe the epidemiological, clinical, diagnostic, therapeutic, and evolutionary aspects of patients with early metastatic prostate cancer in a urology center in the city of Douala in Cameroon. Materials and Methods: It is a retrospective and descriptive study of 110 patients with prostate cancer that was immediately metastatic at diagnosis over a period of six years (from January 2014 to December 2020). Results: The average age of patients at diagnosis was 67.5 years (range: 45 years to 88 years) and 53.63% of patients had body mass indexes greater than 25. Disorders of the lower urinary tract were the main presenting complaint in 55.45% of cases, followed by bone and joint pain in 46.36% of cases. Digital rectal examination was suggestive of prostate cancer in 96.36% of cases with an average total prostatic specific antigen (PSAT) level of 676.9 ng/ml (range: 21.8 to 8832 ng/ml). The diagnosis was made through prostate biopsy in 57 (51.81%) patients or after palliative endoscopic resection of the prostate indicated for lower urinary tract symptoms or even acute urinary retention in 53 (48.18%) patients. Adenocarcinoma of the prostate was the main histologic type, and in 47.27% of cases, the tumor was poorly differentiated with a Gleason’s score of greater than 7. The sites of metastasis were mainly the lymph node (87.27%), bone (56.36%), and both (44.54%). The treatment was palliative and dominated by bilateral pulpectomy in 60% of cases and luteinizing hormone-releasing hormone agonists (Triptorelin 11.25 mg every 3 months) in 44 (40%) of cases. Conclusion: Prostate cancer is a real public health problem in developed countries but also in Africa, especially in Cameroon. It is aggressive cancer that is often diagnosed when metastasis has already occurred. Its man

关键词： Prostate Cancer Metastasis Hormone Therapy Palliative Treatment

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定向管状纤维自修复水泥基复合材料性能研究

定向管状纤维自修复水泥基复合材料性能研究

作者： Soro Dogniman landry（索罗多格·尼曼兰德里）河北工业大学

学位级别：硕士

混凝土开裂是威胁基础设施安全服役的关键问题。混凝土在大型基础设施、工业与民用建筑等工程中长期广泛应用,但由于其抗拉强度低和准脆性,也最容易出现裂缝。结构中的裂缝通常需要定期修复,这不但会使基础设施在一定时期内无法使用,还... 详细信息

混凝土开裂是威胁基础设施安全服役的关键问题。混凝土在大型基础设施、工业与民用建筑等工程中长期广泛应用,但由于其抗拉强度低和准脆性,也最容易出现裂缝。结构中的裂缝通常需要定期修复,这不但会使基础设施在一定时期内无法使用,还会增加工程成本。同时某些裂缝并不能通过人工方法进行修复,如地下结构和放射性废物处理设施。混凝土自修复技术是解决上述问题的方法之一,该方法允许混凝土结构通过自然或人工机制在没有人为干预的情况下自我修复裂缝。基于化学原理来使裂缝自我修复是一种行之有效的方法。因其能够修复一定范围宽度的裂缝,该方法已证明是应用在水泥基材料中最有效的修复方法之一。然而,裂缝自修复一般是向混凝土中掺入含修复剂的胶囊或管状纤维,胶囊或管状纤维随机分布的特性可能使其无法充分接触裂缝,这就限制了其自修复的效果。在本文中,利用内含修复剂的聚偏氟乙烯树脂(PVDF)管状自修复纤维,研究自修复纤维的排列方向对其修复裂缝的能力的影响。首先,研究了PVDF自修复纤维的拉伸强度及其与水泥基体的粘结强度。结果表明,水泥基体发生开裂时,PVDF自修复纤维既具有一定的弹性,同时能够及时开裂以释放其中的修复剂。PVDF自修复纤维和水泥基体之间的粘结强度也能保证纤维开裂而不是发生滑移。其次,研究了PVDF自修复纤维在水泥基体中的定向方法。由于钢纤维可通过磁场力在水泥基体中旋转定向,因此将PVDF自修复纤维与钢纤维结合形成复合纤维。当将掺有复合纤维的拌合物置于匀强磁场中时,钢纤维会因为受到磁场力而发生旋转。相应地,PVDF自修复纤维也会随钢纤维发生旋转。基于此原理,首先制备了两种类型的复合纤维(AHFCC-1SF和AHFCC-2SF,每根自修复纤维上分别绑定一根和两根钢纤维),而后研究了实现混杂纤维定向所需要的最佳的拌合物工作性。结果表明,AHFCC-2SF型纤维定向效果良好,且拌合物工作性(扩展度)应在160-240mm范围。然后,研究了PVDF自修复纤维的排列方向对其修复裂缝能力的影响。首先制备了单向定向(AHFCC)和随机乱向(RHFCC)自修复纤维水泥基复合材料试件,并对每个试件进行了劈拉以使其分别带有270?m和220?mm宽度的裂缝。然后将两种类型的试件养护7天以使裂缝得到修复。修复完成后,测试了两种类型试件的透水性能。结果表明,与RHFCC相比,AHFCC虽然具有较大的裂缝宽度,但其透水能力更低。进一步地,通过劈拉强度测试评价其修复能力。在试件自修复完成后,与RHFCC相比,AHFCC的劈拉强度得到更大程度的恢复。此外,也研究了不同掺量的自修复纤维(体积掺量分别为0%、0.12%和0.18%)对水泥基复合材料抗压强度的影响。结果表明,自修复纤维掺量较高时可能会对抗压强度产生不利影响。综上所述,PVDF自修复纤维与钢纤维结合能够使PVDF自修复纤维跟随钢纤维发生旋转实现定向;沿拉应力分布(垂直于开裂表面)的PVDF自修复纤维显著提高了材料的自修复能力;与RHFCC相比,尽管AHFCC的裂缝宽度更大,但是自修复性能更好;PVDF自修复纤维定向后,能提高跨越裂缝的自修复纤维的数量,开裂时释放更多的修复剂,从而填充或粘结更大裂缝体积(面积)。因此,自修复纤维在基体中定向排列能够有效提高试件的自修复能力。

关键词：自修复修复性能定向修复纤维随机分布修复纤维混杂纤维水泥基复合材料

Epidemiologic and Therapeutic Aspect of Urogenital Fistula Following Obstetric and Gynecologic Surgeries Repaired at the Nkwen Baptist Hospital

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Open Journal of Obstetrics and Gynecology 2023年第3期13卷 427-443页

作者： William Ako Takang Mangoue Moubeariane landry Ngwa Tangang Ebogo Titus Julius Sama Dohbit Faculty of Health Sciences University of Bamenda Bamenda Cameroon Cameroon Baptist Convention Health Services Nkwen Bamenda Cameroon Faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon

Introduction: Urogenital fistula is an abnormal communication between the urinary and the genital systems. It may occur following vaginal deliveries or following pelvic surgeries. Data concerning urogenital fistula post-surgery is limited and we have noticed in recent years in Sub-Saharan Africa, an increase in the burden of iatrogenic urogenital fistula. Objective: The aim of this study was to assess the epidemiology, clinical profiles and therapeutic aspects of urogenital fistula following obstetric and gynaecologic surgeries repaired at the Nkwen Baptist Hospital Bamenda. Materials/Methods: This was a longitudinal descriptive study with a retrospective and prospective phase carried out at the Nkwen Baptist Hospital for 5 months. However the complete duration of the study was about 17 months. Data was collected using a pretested questionnaire containing socio-demographic information, clinical features, and therapeutic methods used. We used the statistical software SPSS (Social Package for Statistical Sciences) V 26.0 for data analysis. Results: The number of participants in the study was 40. The mean age was 43.5 years (+/- 13.3) ranging from 16 - 74 years. The prevalence of urogenital fistula post obstetric and gynecologic surgeries at the Nkwen Baptist hospital was 64.6%. The most common symptom was urine leakage and the most common surgery that exposed the patient to the urogenital fistula was total abdominal hysterectomy (60%) followed by caesarean section (35%). The different indications for these surgeries were mostly symptomatic leiomyoma (70.8 %) and prolonged labor (64.2%) respectively. The different types of fistula encountered were Vesicovaginal fistula (55%), Ureterovaginal fistula 40% and Vesicoutetrine fistula 5%. The different treatment modalities used were trans abdominal (77.5%) and transvaginal repair (22.5%). The overall repair success rate after one month was 85%. Conclusion: There is high burden of urogenital fistula post surgeries in our sett

关键词： Urogenital Fistula Obstetric Surgery Gynecologic Surgery