2 . 연구원 활동 : 3 ) 발표논문요약 < 금속공학분야 >

(E . Schroer),(S . Hopfe),(J . Y . Huh),(U . Gosele) 고려대학교 공학기술연구소 1997 공학기술연구소보 Vol.4 No.-

HELIUM3D: A Laser-scanning Head-tracked Autostereoscopic Display

Brar, Rajwinder Singh,Surman, Phil,Sexton, Ian,Hopf, Klaus The Korean Infomation Display Society 2010 Journal of information display Vol.11 No.3

A multi-user autostereoscopic display based on laser scanning is described in this paper. It does not require the wearing of special glasses; it can provide 3D to several viewers who have a large degree of freedom of movement; and it requires the display of only a minimum amount of information. The display operates by providing regions in the viewing field, referred to as "exit pupils," which follow the positions of the viewers' eyes under the control of a multi-user head tracker. The display incorporates an RGB laser illumination source that illuminates a light engine. The light directions are controlled by a spatial light modulator, and a front screen assembly incorporates a novel Gabor superlens. Its operating principle is explained in this paper, as is the construction of three iterations of the display. Finally, a method of developing the display into one that is suitable for television applications is described.

A Time-multiplexed 3d Display Using Steered Exit Pupils

Brar, Rajwinder Singh,Surman, Phil,Sexton, Ian,Hopf, Klaus The Korean Infomation Display Society 2010 Journal of information display Vol.11 No.2

This paper presents the multi-user autostereoscopic 3D display system constructed and operated by the authors using the time-multiplexing approach. This prototype has three main advantages over the previous versions developed by the authors: its hardware was simplified as only one optical array is used to create viewing regions in space, a lenticular multiplexing screen is not necessary as images can be produced sequentially on a fast 120Hz LCD with full resolution, and the holographic projector was replaced with a high-frame-rate digital micromirror device (DMD) projector. The whole system in this prototype consists of four major parts: a 120Hz high-frame-rate DMD projector, a 49-element optical array, a 120Hz screen assembly, and a multi-user head tracker. The display images for the left/right eyes are produced alternatively on a 120Hz direct-view LCD and are synchronized with the output of the projector, which acts as a backlight of the LCD. The novel steering optics controlled by the multiuser head tracker system directs the projector output to regions referred to as exit pupils, which are located in the viewers’eyes. The display can be developed in the "hang-on-the-wall"form.

A Time-multiplexed 3d Display Using Steered Exit Pupils

Rajwinder Singh Brar,Phil Surman,Klaus Hopf,Ian Sextona 한국정보디스플레이학회 2010 Journal of information display Vol.11 No.2

This paper presents the multi-user autostereoscopic 3D display system constructed and operated by the authors using the time-multiplexing approach. This prototype has three main advantages over the previous versions developed by the authors: its hardware was simplified as only one optical array is used to create viewing regions in space, a lenticular multiplexing screen is not necessary as images can be produced sequentially on a fast 120Hz LCD with full resolution, and the holographic projector was replaced with a high-frame-rate digital micromirror device (DMD) projector. The whole system in this prototype consists of four major parts: a 120Hz high-frame-rate DMD projector, a 49-element optical array, a 120Hz screen assembly, and a multi-user head tracker. The display images for the left/right eyes are produced alternatively on a 120Hz direct-view LCD and are synchronized with the output of the projector, which acts as a backlight of the LCD. The novel steering optics controlled by the multiuser head tracker system directs the projector output to regions referred to as exit pupils, which are located in the viewers’ eyes. The display can be developed in the “hang-on-the-wall” form.

Short-Term Student Exchanges for Aspiring International Activities of Engineering Students

Sato, Takashi,Sakamoto, Shuichi,Shimizu, Tadaaki,Suzuki, Takamasa,Ikeda, Hideki,Hopf, Anja,Goto, Yasushi,Oka, Tetsuo,Sasaki, Tomohiro,Narumi, Takatsune Korean Society for Engineering Education 2014 공학교육연구 Vol.17 No.4

The Faculty of Engineering, Niigata University, Japan, obtained the scholarship in "Short-Stay and Short-Visit scholarship programs(SS-SV programs)" for both German and Japanese students in 2011 and 2012. Our short-term student exchange programs proved that a short-term stay in a foreign country worked as an initiator for the students' interest and it strengthen their will to study further more in foreign countries.

Short-Term Student Exchanges for Aspiring International Activities of Engineering Students

Takashi Sato,Shuichi Sakamoto,Tadaaki Shimizu,Takamasa Suzuki,Hideki Ikeda,Anja Hopf,Yasushi Goto,Tetsuo Oka,Tomohiro Sasaki,Takatsune Narumi 한국공학교육학회 2014 공학교육연구 Vol.17 No.4

The Faculty of Engineering, Niigata University, Japan, obtained the scholarship in “Short-Stay and Short-Visit scholarshipprograms(SS-SV programs)” for both German and Japanese students in 2011 and 2012. Our short-term student exchange programsproved that a short-term stay in a foreign country worked as an initiator for the students' interest and it strengthen their will tostudy further more in foreign countries.

Incidence and characteristics of major bleeding among rivaroxaban users with renal disease and nonvalvular atrial fibrillation

Manesh R. Patel,W. Frank Peacock,Sally Tamayo,Nicholas Sicignano,Kathleen P. Hopf,Zhong Yuan 대한응급의학회 2018 Clinical and Experimental Emergency Medicine Vol.5 No.1

Objective Patients with nonvalvular atrial fibrillation (AF) and renal disease (RD) who receive anticoagulation therapy appear to be at greater risk of major bleeding (MB) than AF patients without RD. As observed in past studies, anticoagulants are frequently withheld from AF patients with RD due to concerns regarding bleeding. The objective of this study was to evaluate the incidence and pattern of MB in those with RD, as compared to those without RD, in a population of rivaroxaban users with nonvalvular AF. Methods Electronic medical records of over 10 million patients from the Department of Defense Military Health System were queried to identify rivaroxaban users with nonvalvular AF. A validated algorithm was used to identify MB-related hospitalizations. RD was defined through diagnostic codes present within 6 months prior to the bleeding date for MB cases and end of study participation for non-MB patients. Data were collected on patient characteristics, comorbidities, MB management, and outcomes. Results Overall, 44,793 rivaroxaban users with nonvalvular AF were identified. RD was present among 6,921 patients (15.5%). Patients with RD had a higher rate of MB than those without RD, 4.52 per 100 person-years versus 2.54 per 100 person-years, respectively. The fatal bleeding outcome rate (0.09 per 100 person-years) was identical between those with and without RD. Conclusion In this post-marketing study of 44,793 rivaroxaban users with nonvalvular AF, RD patients experienced a higher MB rate than those without RD. The higher rate of MB among those with RD may be due to the confounding effects of comorbidities.

Dislocations as native nanostructures - electronic properties

Reiche, Manfred,Kittler, Martin,Uebensee, Hartmut,Pippel, Eckhard,Hopfe, Sigrid Techno-Press 2014 Advances in nano research Vol.2 No.1

Dislocations are basic crystal defects and represent one-dimensional native nanostructures embedded in a perfect crystalline matrix. Their structure is predefined by crystal symmetry. Two-dimensional, self-organized arrays of such nanostructures are realized reproducibly using specific preparation conditions (semiconductor wafer direct bonding). This technique allows separating dislocations up to a few hundred nanometers which enables electrical measurements of only a few, or, in the ideal case, of an individual dislocation. Electrical properties of dislocations in silicon were measured using MOSFETs as test structures. It is shown that an increase of the drain current results for nMOSFETs which is caused by a high concentration of electrons on dislocations in p-type material. The number of electrons on a dislocation is estimated from device simulations. This leads to the conclusion that metallic-like conduction exists along dislocations in this material caused by a one-dimensional carrier confinement. On the other hand, measurements of pMOSFETs prepared in n-type silicon proved the dominant transport of holes along dislocations. The experimentally measured increase of the drain current, however, is here not only caused by an higher hole concentration on these defects but also by an increasing hole mobility along dislocations. All the data proved for the first time the ambipolar behavior of dislocations in silicon. Dislocations in p-type Si form efficient one-dimensional channels for electrons, while dislocations in n-type material cause one-dimensional channels for holes.