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3-아미노-1H-피라졸-4-카르복실산 에틸의 디아조화와 결합반응;피라졸로아진의 합성
Youssef, Ayman M.S.,Faty, Rasha A.M.,Youssef, Mohamed M. 대한화학회 2001 대한화학회지 Vol.45 No.5
피라졸로아진은 농업이나 의약품에서 매우 유용한 화합물등이다. 본 논문에서는 몇 가지 새로운 피라졸로아진의 합성을 보고하고자 한다. 표제 화합물인 3-아미노-1H-피라졸-4-카복실산 에틸을 다이아조화한 후 활성화된 메틸렌 화합물들과 반응시키고 고리화하여 피라졸로[5,1-c][1,2,4]트라이아진 유도체들을 합성하였다. 또한 표제 화합물을 $\alpha$-치환된 신남나이트릴과 반응시켜 피라졸로[1,5-a]피리미딘 유도체들을 합성하였다. 새로 합성된 화합물들의 구조는 화학적 방법과 분광학적 방법을 사용하여 확립하였다. Pyrazoloazines are extremely useful in agriculture and medicine. The main objective of this article is to synthesize some new pyrazoloazines. Ethyl 3-amino-1H-pyrazole-4-carboxylate undergoes diazotization, couples with activated methylene compounds and cyclizes to form pyrazolo[5,1-c][1,2,4]tri-azine derivatives. The title compound also reacts with $\alpha$-substituted cinnamonitriles to produce pyrazolo[1,5-a]pyrimidine derivatives. Structures of newly synthesized compounds are established via chemical and spectral methods.
Rochd Sara,Benhoummad Othmane,Salhi Salma,Lakhdar Youssef,Rochdi Youssef,Raji Abdelaziz,Oualhadj Hamza,Kamouni Youssef El,Zouhair Said 대한청각학회 2024 Journal of Audiology & Otology Vol.28 No.1
Lyme neuroborreliosis (LNB) is a rare but potentially serious manifestation of Lyme disease, caused by the spirochete <i>Borrelia burgdorferi</i>. Although LNB can affect various neurological systems, neurosensory hearing loss as the sole presentation is uncommon. We report a case of a 23-year-old woman who presented with a 2-month history of temporal headache, tinnitus, and instability, which was followed by sudden bilateral hearing loss without any other associated symptoms. Pure-tone audiometry revealed profound bilateral hearing loss. Serological testing for various pathogens was negative, except for <i>B. burgdorferi</i> IgM, which was confirmed using Western blot analysis. The patient received doxycycline treatment; unfortunately, no recovery of hearing was observed. This case report highlights the importance of considering LNB as a potential cause of neurosensory hearing loss, particularly in areas where Lyme disease is endemic, as well as the need for timely diagnosis and treatment to prevent potential complications.
Youssef N. Raffoul 대한수학회 2018 대한수학회보 Vol.55 No.6
We consider a functional difference equation and use fixed point theory to obtain necessary and sufficient conditions for the asymptotic stability of its zero solution. At the end of the paper we apply our results to nonlinear Volterra infinite delay difference equations.
CFD Simulation Tool for Anode-Supported Flat-Tube Solid Oxide Fuel Cell
Youssef M. Elsayed.,Lim, Tak-Hyoung,Song, Rak-Hyun,Lee, Seung-Bok,Shin, Dong-Ryul The Korean Electrochemical Society 2006 한국전기화학회지 Vol.9 No.4
A two-dimensional numerical model to study the performance of anode-supported flat-tube solid oxide fuel cell (SOFC) far the cross section of the cell in the flow direction of the fuel and air flows is developed. In this model a mass and charge balance, Maxwell-Stefan equation as well as the momentum equation by using, Darcy's law are applied in differential form. The finite element method using FEMLAB commercial software is used for meshing, discritization and solving the system of coupled differential equations. The current density distribution and fuel consumption as well as water production are analyzed. Experimental data is used to verify a predicted voltage-current density and power density versus current density to judge on the model accuracy.
Youssef S. Al Jabbari 대한치과보철학회 2011 The Journal of Advanced Prosthodontics Vol.3 No.4
Maxillary labial and buccal frena are considered as normal anatomic structures in the oral cavity. However, they may exist intraorally as a thick broad fibrous attachment and/or become located near the crest of the residual ridge, thus interfering with proper denture border extension resulting in inferior denture stability, retention and overall patient satisfaction. This case report highlights the importance of clinical examination and treatment planning which may mandate preprosthetic surgery prior to fabrication of a new conventional complete denture. Adequate patient satisfaction with conventional complete dentures can be significantly increased after frenectomy.
Gastric Duplication Cyst Presenting as Massive Gastrointestinal Bleeding
Youssef, Alexey,Ibrahim, Alexander,AlShehabi, Zuheir,Omran, Ammar,Sharara, Ala I. The Korean Society of Pediatric Gastroenterology 2019 Pediatric gastroenterology, hepatology & nutrition Vol.22 No.2
Gastric duplication cysts (GDCs) are rare congenital anomalies. Presentation of GDCs varies from an asymptomatic abdominal mass to fulminant or massive gastrointestinal (GI) bleeding. Herein, we describe a case of a GDC in a 10-month-old infant presenting with unexplained massive GI hemorrhage and hematemesis. An abdominal ultrasound was negative, while computerized tomography was, initially, inaccessible. Through a series of repeated esophagogastroduodenoscopies, we documented penetration of the GDC into the gastric cavity that was later confirmed by computerized tomography. The patient was treated successfully with surgical resection.
Hazard identification and scenario selection of ship grounding accidents
Youssef, Samy Adly Mansour,Paik, Jeom Kee Elsevier 2018 Ocean engineering Vol.153 No.-
<P><B>Abstract</B></P> <P>The objectives of the present paper are to identify the hazard of ship grounding; where a ship runs on a rock with a forward speed, and to select a set of credible scenarios with a limited number that can still represent all possible situations of the accidents. For this purpose, the statistics of ship grounding accidents recorded by authorities for the period of 46 years during 1970–2016 are collated. An extensive analysis is undertaken to examine the statistical characteristics in association with random variables influencing the consequence of grounding. A total of six parameters, namely ship's forward speed, ship's trim angle, rock tip eccentricity, rock length, rock width and rock height are considered as random variables where the displacement or mass of the grounded ship is fixed. Each of the random variables is then formulated with a probability density function. A sampling technique is applied to the probabilistic selection of the grounding scenarios which are to be used for the consequence analysis within the framework of quantitative risk assessment. Important insights developed from the present study are discussed. Details of the analyses are documented.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This article aims to identify the hazard of ship grounding to select a set of scenarios represent all possible situations. </LI> <LI> Statistics of ship grounding accidents recorded by authorities are collated. </LI> <LI> Extensive analyses are performed to examine the statistical characteristics with random variables of grounding. </LI> <LI> A sampling technique is applied to the probabilistic selection of the grounding scenarios. </LI> <LI> Selected credible scenarios are essential within the framework of quantitative grounding risk assessment and management. </LI> </UL> </P>
Towards Robust Key Extraction from Multipath Wireless Channels
Youssef El Hajj Shehadeh,Omar Alfandi,Dieter Hogrefe 한국통신학회 2012 Journal of communications and networks Vol.14 No.4
This paper tackles the problem of generating shared secret keys based on the physical characteristics of the wireless channel. We propose intelligent quantization mechanisms for key generation,achieving high secret bits generation rate. Moreover, some practical issues affecting the performance of the key generation mechanism are deeply investigated. Mainly, we investigate the effects of delay and mobility on the performance and we enhance the key generation mechanism accordingly. As a result, this paper presents a framework towards robust key generation from multipath wireless channels.
SAMT: Shape-aware Multi-task Deep Convolutional Model for Crack Identification
Youssef Oumate(우마트 유셉),Seongmin Kim(김성민),JeanPierre Lomaliza(로말리자 장피에르),Joonhyeok Shin(신준혁),Jiyoung Lee(이지영),Seowoo Han(한서우) 대한전자공학회 2023 대한전자공학회 학술대회 Vol.2023 No.6
In this paper, we present a novel pipeline for crack classification using a multi-task model. Our model consists of two branches: a classification branch that distinguishes between crack and no crack images, and a segmentation branch that locates the crack region in the image. By combining these two tasks, our model can focus more on the crack itself and avoid being distracted by the surrounding regions. We also use the segmentation output to extract shape features from the crack region and combine them with the classification output to obtain a final crack score. This way, we can reduce the false positive rate significantly and achieve stateof-the-art results on various public datasets. We demonstrate that our multi-task model for crack identification is simple yet effective, achieving 87.29% and 90.14% Average Precision on SDNet2018 and Concrete Crack Images for Classification datasets, recursively.