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On-the-fly dopant redistribution in a silicon nanowire p-n junction

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Nano Research 2017年第8期10卷 2845-2855页

作者： Dong-II Moon Myeong-lok Seol Jin-Woo Han M. Meyyappan Center for Nanotechnology NASA Ames Research Center Moffett Field CA 94035 USA

Dopant redistribution in a silicon nanowire （SiNW） p-n junction is found to occur owing to self-heating effects. A SiNW is doped to form back-to-back diodes and is thermally isolated by an oxide layer on its bottom side and by air on the other sides. When a high level of current flows, the inner body temperature is found to increase enough to cause dopant diffusion and even to reach the silicon melting point due to Joule heating. This experimentally observed electrothermal behavior is also validated through numerical simulation. The conductivity change is dependent on the total power density and the change becomes permanent once the device suffers self-heating beyond a threshold point. Finally, the dopant redistribution is directly visualized using scanning capacitance microscopy for the first time.

关键词： nanowire degradation Joule heating dopant redistribution scanning capacitance microscopy

A molecular arms race between host innate antiviral response and emerging human coronaviruses

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Virologica Sinica 2016年第1期31卷 12-23页

作者： lok-Yin Roy Wong Pak-Yin Lui Dong-Yan Jin School of Biomedical Sciences The University of Hong Kong

Coronaviruses have been closely related with mankind for thousands of years. Communityacquired human coronaviruses have long been recognized to cause common cold. However,zoonotic coronaviruses are now becoming more a global concern with the discovery of highly pathogenic severe acute respiratory syndrome(SARS) and Middle East respiratory syndrome(MERS) coronaviruses causing severe respiratory diseases. Infections by these emerging human coronaviruses are characterized by less robust interferon production. Treatment of patients with recombinant interferon regimen promises beneficial outcomes, suggesting that compromised interferon expression might contribute at least partially to the severity of disease. The mechanisms by which coronaviruses evade host innate antiviral response are under intense investigations. This review focuses on the fierce arms race between host innate antiviral immunity and emerging human coronaviruses. Particularly, the host pathogen recognition receptors and the signal transduction pathways to mount an effective antiviral response against SARS and MERS coronavirus infection are discussed. On the other hand, the counter-measures evolved by SARS and MERS coronaviruses to circumvent host defense are also dissected. With a better understanding of the dynamic interaction between host and coronaviruses, it is hoped that insights on the pathogenesis of newly-identified highly pathogenic human coronaviruses and new strategies in antiviral development can be derived.

关键词： MERS-CoV SARS-CoV innate antiviral response type I interferons immune evasion

TransHist:Occlusion-robust shape detection in cluttered images

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Computational Visual Media 2018年第2期4卷 161-172页

作者： Chu Han Xueting Liu lok Tsun Sinn Tien-Tsin Wong The Chinese University of Hong Kong Hong Kong China.

Shape matching plays an important role in various computer vision and graphics applications such as shape retrieval, object detection, image editing,image retrieval, etc. However, detecting shapes in cluttered images is still quite challenging due to the incomplete edges and changing perspective. In this paper, we propose a novel approach that can efficiently identify a queried shape in a cluttered image. The core idea is to acquire the transformation from the queried shape to the cluttered image by summarising all pointto-point transformations between the queried shape and the image. To do so, we adopt a point-based shape descriptor, the pyramid of arc-length descriptor(PAD),to identify point pairs between the queried shape and the image having similar local shapes. We further calculate the transformations between the identified point pairs based on PAD. Finally, we summarise all transformations in a 4 D transformation histogram and search for the main cluster. Our method can handle both closed shapes and open curves, and is resistant to partial occlusions. Experiments show that our method can robustly detect shapes in images in the presence of partial occlusions, fragile edges, and cluttered backgrounds.

关键词： shape matching shape detection transformation histogram

Electromagnetic wave propagation of wireless capsule endoscopy in human body

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Journal of Central South University 2013年第10期20卷 2650-2656页

作者： LIM Eng-Gee 王炤陈瑾慧 TILLO Tammam MAN Ka-lok Department of Electronic and Electrical Engineering Xi’an Jiaotong-Liverpool University

Wireless capsule endoscopy(WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine section. However, this technique is still far from mature and asks for the feasible improvements. For example, the relatively low transmission data rate and the absence of the real-time localization information of the capsule are all important issues. The studies of them rely on the understanding of the electromagnetic wave propagation in human body. Investigation of performance of WCE communication system was carried out by studying electromagnetic(EM) wave propagation of the wireless capsule endoscopy transmission channel. Starting with a pair of antennas working in a human body mimic environment, the signal transmissions and attenuations were examined. The relationship between the signal attenuation and the capsule(transmitter) position, and direction was also evaluated. These results provide important information for real-time localization of the capsule. Moreover, the pair of antennas and the human body were treated as a transmission channel, on which the binary amplitude shift keying(BASK) modulation scheme was used. The relationship between the modulation scheme, data rate and bit error rate was also determined in the case of BASK. With the obtained studies, it make possible to provide valuable information for further studies on the selection of the modulation scheme and the real-time localization of the capsules.

关键词： wireless capsule electromagnetic wave propagation transmission channel

香港地区中学文凭考试诊断反馈系统的开发及改进

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中国考试 2024年第2期 40-46页

作者：禤美瑶萧伟乐周钜宽杨汉基席小明香港考试及评核局中国香港999077

为进一步推动“评核促进学习”,香港地区考试及评核局以历年香港地区中学文凭考试(HKDSE)的评核数据为基础开发了HKDSE诊断反馈系统。目前,该系统结合HKDSE 6个科目选择题的试题库,对学生学习表现数据加以分析并建立统计模型,为教师与... 详细信息

为进一步推动“评核促进学习”,香港地区考试及评核局以历年香港地区中学文凭考试(HKDSE)的评核数据为基础开发了HKDSE诊断反馈系统。目前,该系统结合HKDSE 6个科目选择题的试题库,对学生学习表现数据加以分析并建立统计模型,为教师与学生提供诊断性反馈报告,突出学生在不同能力或范畴的不足与强项。来自14所学校的约2200名学生及教师试用了该系统,通过问卷调查和访谈法,收集意见建议,以改进系统设计。系统改良版在“数据主导评核提升计划”中正式推出,辅之以学科教师培训,以帮助学校提升评核质量。

关键词：香港地区中学文凭考试诊断反馈评核促进学习个性化学习

Importance of Air-Sea Coupling in Simulating Tropical Cyclone Intensity at Landfall

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Advances in Atmospheric Sciences 2022年第10期39卷 1777-1786页

作者： Charlie C.F.lok Johnny C.L.CHAN Ralf TOUMI School of Energy and Environment City University of Hong KongHong KongChina Department of Physics Imperial CollegeLondon SW72AZUK

An atmosphere-only model system for making seasonal prediction and projecting future intensities of landfalling tropical cyclones(TCs)along the South China coast is upgraded by including ocean and wave models.A total of 642 TCs have been re-simulated using the new system to produce a climatology of TC intensity in the South China *** comparisons of the simulations from the atmosphere-only and the fully coupled systems reveal that the inclusion of the additional ocean and wave models enable differential sea surface temperature responses to various TC characteristics such as translational speed and *** particular,interaction with the ocean does not necessarily imply a weakening of the TC,with the coastal bathymetry possibly playing a role in causing a near-shore intensification of the *** results suggest that to simulate the evolution of TC structure more accurately,it is essential to use an air-sea coupled model instead of an atmosphere-only model.

关键词： tropical cyclone intensity tropical cyclone landfall seasonal prediction air-sea coupling

Temperature-and thickness-dependence of robust out-of-plane ferroelectricity in CVD grown ultrathin van der Waals a-In2Se3 layers

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Nano Research 2020年第7期13卷 1897-1902页

作者： Weng Fu Io Shuoguo Yuan Sin Yi Pang lok Wing Wong Jiong Zhao Jianhua Hao Department of Applied Physics The Hong Kong Polytechnic UniversityHong KongChina

Two-dimensional(2D)ferroelectric materials with unique structure and extraordinary optoelectrical properties have attracted intensive research in the field of nanoelectronic and optoelectronic devices,such as optical sensors,transistors,photovoltaics and non-volatile memory ***,the transition temperature of the reported ferroelectrics in 2D limit is generally low or slightly above room temperature,hampering their applications in high-temperature electronic ***,we report the robust high-temperature ferroelectricity in 2D a-In2Se3,grown by chemical vapor depostion(CVD),exhibiting an out-of-plane spontaneous polarization reaching above 200℃.The polarization switching and ferroelectric domains are observed in In2Se;nanoflakes in a wide temperature *** coercive field of the CVD grown ferroelectric layers ilustrates a room-temperature thickness dependency and increases drastically when the film thickness decreases;whereas there is no large variance in the coercive field at dfterent termperature from the samples with identical *** results show the stable ferroelectricit of In2Se3 nanoflakes maintained at high temperature and open up the opportunities of 2D materials for novel applications in high-temperature nanoelectronic devices.

关键词： ln2Se3 two-dimensional(2D)materials ferroelectricity high-temperature coercive field

Corneal injection track: an unusual complication of intraocular lens implantation and review

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International Journal of Ophthalmology(English edition) 2015年第3期8卷 631-633页

作者： Julie Y.C.lok Alvin L.Young Department of Ophthalmology & Visual Sciences the Chinese University of Hong Kong Prince of Wales Hospital Alice Ho Miu Ling Nethersole Hospital

Phacoemulsification is the main gold standard for cataract operation in the developed world together with foldable intraocular lens(IOL) implantation by injection,allowing for stable wound construction and less postoperative astigmatism. It is a safe procedure with high success rate with the advancement in machines,improvement of IOL injection systems and further maturation of surgeons’ techniques. Despite the large number of operations performed every day, foldable IOL injection leading to an intra-stromal corneal track is a very rare complication. We report a case of this unusual finding in a 70-year-old gentleman who has undergone cataract operation in November 2011 in our hospital and will review on the complications related to foldable IOL injection.

关键词： foldable intraocular lens phacoemulsification cornea complications

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宮頸液基細胞學檢測原發性宮頸淋巴瘤1例

镜湖医学 2024年第1期24卷 61-61,60,F0004页

作者：陳頌敏李文洛陳建勇澳門鏡湖醫院病理科中国

原發女生殖系統淋巴瘤較少見,佔全身結外淋巴瘤1%[1],其中原發性宮頸淋巴瘤(primary cervical lymphoma,PCL)更是罕見的婦科惡性腫瘤,佔宮頸腫瘤0.008%[2,3]。宮頸淋巴瘤起源於宮頸黏膜淋巴組織,症狀包括陰道出血、白帶增多、下腹痛和... 详细信息

原發女生殖系統淋巴瘤較少見,佔全身結外淋巴瘤1%[1],其中原發性宮頸淋巴瘤(primary cervical lymphoma,PCL)更是罕見的婦科惡性腫瘤,佔宮頸腫瘤0.008%[2,3]。宮頸淋巴瘤起源於宮頸黏膜淋巴組織,症狀包括陰道出血、白帶增多、下腹痛和盆腔腫塊,與其他婦科疾病症狀相似,容易誤診。

关键词：淋巴瘤女生殖系下腹痛液基