• Title/Summary/Keyword: focal region

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대칭 및 비대칭 binary filter가 수차를 포함한 광학계의 축상 GAIN에 미치는 영향

  • 최기준;정창섭;심상현
    • Korean Journal of Optics and Photonics
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    • v.12 no.3
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    • pp.165-171
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    • 2001
  • We discuss the influence of annular binary filters on the axial PSF of imaging systems which are apodized by a radiallysymmetric filter and have spherical aberration and coma. In this paper we consider a whole family of annular binary fIlters in two cases. First, the binary filters are composed of two transparent annuli of the same area. Second, the binary filters are composed of a central clear circle and a concentric annular aperture with area bigger than that of the inner circle. In order to investigate the influence of the proposed filters on the axial PSF, we may use the axial resolution gains, which evaluate in terms of the FWHM of the intensity in the focal region of an apodized imaging system in comparison with that corresponding to a nonapodized one. We evaluate the PSF for the conventional and confocal systems having an aberration. ation.

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Study on The Electron-Beam Optics in The Micro-Column for The Multi-Beam Lithography (다중빔 리소그래피를 위한 초소형 컬럼의 전자빔 광학 해석에 관한 연구)

  • Lee, Eung-Ki
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.4
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    • pp.43-48
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    • 2009
  • The aim of this paper is to describe the development of the electron-beam optic analysis algorithm for simulating the e-beam behavior concerned with electrostatic lenses and their focal properties in the micro-column of the multi-beam lithography system. The electrostatic lens consists of an array of electrodes held at different potentials. The electrostatic lens, the so-called einzel lens, which is composed of three electrodes, is used to focus the electron beam by adjusting the voltages of the electrodes. The optics of an electron beam penetrating a region of an electric field is similar to the situation in light optics. The electron is accelerated or decelerated, and the trajectory depends on the angle of incidence with respect to the equi-potential surfaces of the field. The performance parameters, such as the working distances and the beam diameters are obtained by the computational simulations as a function of the focusing voltages of the einzel lens electrodes. Based on the developed simulation algorithm, the high performance of the micro-column can be achieved through optimized control of the einzel lens.

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Soft Tissue Sarcomas Originating from Retroperitoneal Cavity in a Maltese Dog (후복강에서 기원한 비혈관성 연부조직 육종 증례)

  • Shin, Jung-Min;Park, Seuingjo;Lee, Sang-Kwon;Choi, Jihye
    • Journal of Veterinary Clinics
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    • v.32 no.1
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    • pp.115-119
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    • 2015
  • An 11-year-old spayed female maltese was presented for abdominal distention, dysuria and dyschezia. Panting and heart murmur was found and abdominal palpation was difficult due to increased abdominal pressure. A soft tissue mass, $6{\times}3cm$ in size, was identified radiographically in pelvic canal, displacing the descending colon to the medioventral direction and the urinary bladder cranially. On ultrasonography, the mass consisted of homogeneous hypoechoic parenchyma containing the focal hyperechoic region ($1.6{\times}1.5cm$). The mass had distinct margin and no connection with adjacent organs. It was considered as a mass originating from the retroperitoneal cavity. Additional diagnostic procedures were not advanced because of the owner's request, and only a surgical excision of the mass was performed to alleviate the dysuria and dyschezia. Histopathologic examination and immunohistochemistry determined the mass as a soft tissue sarcoma and excluded hemangiosarcoma and osteosarcoma, both are the most common types of the retroperitoneal tumors. This report described non-vascular soft tissue sarcoma originating from the retroperitoneal cavity in a maltese dog.

Reconstruction of extensive jaw defects induced by keratocystic odontogenic tumor via patient-customized devices

  • Park, Seok-Yong;Shin, Young-Jo;Kim, Chul-Hoon;Kim, Bok-Joo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.37
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    • pp.37.1-37.4
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    • 2015
  • Keratocystic odontogenic tumors can occur in any area of the maxilla or mandible. According to their size, location, and relations with surrounding structures, they are treated by cyst enucleation or enucleation after either marsupialization or decompression. Enucleation is performed when cysts are not large and when only minor damage to adjacent anatomical structures is expected. Although marsupialization and decompression follow the same basic bone-regeneration principle, which is to say, by reducing the pressure within the cyst, the former leaves a large defect after healing due to the large fistula necessary to induce the conversion of the cyst-lining epithelia to oral epithelia; the latter leaves only a relatively small defect, because of the continuous washing carried out by means of a tube inserted into a small hole in the cyst. In the latter case too, a decompressor appropriate for the focal position is required, owing to the importance of maintaining the device and controlling for oral hygiene. We report herein decompression treatment with a patient-customized device for an extensive cyst in the anterior region of the mandible.

Heart Failure Occurred during Endoscopic Transthoracic Sympathetic Cauterization -A case report- (흉강경하 교감신경절 소작술중 발생한 심부전 -증례 보고-)

  • Lee, Youn-Woo;Yoon, Duck-Mi;Ahn, Eun-Kyoung;Seouk, Mi-Ja
    • The Korean Journal of Pain
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    • v.9 no.1
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    • pp.235-238
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    • 1996
  • Hyperhidrosis is the distressing condition of abnormal sweating which affects the palm, sole and axillary region. Transthoracic endoscopic sympathectomy is recommended as the treatment of choice for hyperhidrosis, especially when the upper limbs are affected. We experienced a case of accidental cauterization of right azygos vein in a healthy 23 year old male during endoscopic transthoracic sympathectomy. We changed the single lumen endotracheal tube to a double lumen tube which made it easier to perform the explo-thoracotomy and bleeder ligation under one lung ventilation. Crystalloid and colloid solutions, and packed RBC were loaded during explo-thoracotomy. Monitoring showed the signs indicating pulmonary edema. Pulmonary arterial catheterization revealed global heart failure. The patient was transfered to ICU for intensive management for heart failure. On the 4th postoperative day, pulmonary edema and heart failure were cured; and the patient was extubated. But in the evening of the same day ST-segment elevation and Q-wave were noted on ECG monitoring. On the 13th postoperative day coronary angiography was performed. This revealed left apex focal hypokinesia, patent coronary artery and accidental right coronary spasm, treated by vasodilator. On the 14 day, after surgery, he was discharged to return to work.

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Characteristics of Surface Hardening for Hot Work Tool Steel using Continuous Wave Nd:YAG Laser (연속파형 Nd:YAG 레이저를 이용한 열간금형 공구강의 표면경화 특성)

  • Shin, Ho-Jun;Shin, Byung-Heon;Yoo, Young-Tae
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.4 s.193
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    • pp.57-67
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    • 2007
  • Laser surface hardening technologies have been used to improve characteristics of wear and to enhance the fatigue resistance fur mold parts. The objective of this research work is to investigate the influence of the process parameters, such as power of laser and defocused spot position, on the characteristics of laser surface hardening for the case of SKD61 steel. CW Nd:YAG laser is selected as the heat source. The optical lens with the elliptical profile is designed to obtain a wide surface hardening area with a uniform hardness. From the results of the experiments, it has been shown that the maximum average hardness is approximatly 780 Hv when the power, focal position and the travel of laser are 1,095 W, 0mm and 0.3 m/min, respectively. In samples treated with lower scanning speeds, some small carbide particles appear in the interdendritic regions. This region contains fine martensite and carbide in proportions which depend on the local thermal cycle.

Cavitation Effects on Radiated Sounds and Break Efficiency Induced by Piezoelectric Extracorporeal Shock Wave Lithotripter (ESWL 장치에 의한 방사음 및 파쇄효율에 미치는 캐비테이션의 영향)

  • 장윤석
    • Journal of Biomedical Engineering Research
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    • v.22 no.2
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    • pp.205-210
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    • 2001
  • The effectiveness of extracorporeal shock wave lithotripter for the therapy of calculus has been well known in the field of urology. There are many studies about the performance of that and the influence into human body. Among them, it is an impertant issue that cavitation is always deal with shock wave. A medium of the shock wave is related to the cavitation phenomenon. In this paper, therefore, we analysis the spectra of radiated sounds and the break efficiency on focal region due to the medium of shock wave. The results show that the cavitation bubbles produce a harmful on the break efficiency and the stability of the radiated sounds due to the ESWL.

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Earthquake Mechanism in and around the Korean Peninsula (한반도 및 인근의 지진 메카니즘 특성)

  • Jun, Myung-Soon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2008.10a
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    • pp.1-5
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    • 2008
  • In and around the Korean Peninsula, 9 intraplate earthquake mechanisms since 1936 were analyzed to understand the regional stress orientation and tectonics. These earthquakes are largest ones in this century and may represent the characteristics of earthquake in this region. Focal mechanism of these earthquakes show predominant strike-slip faulting with small amount of thrust components. The average P-axis is almost horizontal ENE-WSW. This indicate that not only the subducting Pacific Plate but also the indenting Indian Plate controls earthquake mechanism in the far east of the Eurasian Plate.

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Study of ion beam shaping of an anode-type ion source coupled with a Whenelt mask

  • Huh, Yunsung;Hwang, Yunseok;Kim, Jeha
    • Applied Science and Convergence Technology
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    • v.27 no.4
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    • pp.70-74
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    • 2018
  • We fabricated an anode-type ion source driven by a charge repulsion mechanism and investigated its beam shape controlled by a Whenelt mask integrated at the front face of the source. The ion beam shape was observed to vary by changing the geometry of the Whenelt mask. As the angle of inclination of the Whenelt mask was varied from $40^{\circ}$ to $60^{\circ}$, the etched area at a thin film was reduced from 20 mm to 7.5 mm at the working distance of 286 mm, and the light transmittance through the etched surface was increased from 78% to 80%, respectively. In addition, for the step height difference, ${\Delta}$ between the inner mask and the outer mask of ${\Delta}=0$, -1 mm, and +1 mm, we observed the ion beam shape was formed to be collimated, diverged, and focused, respectively. The focal length of the focused beam was 269 mm. We approved experimentally a simple way of controlling the electric field of the ion beam by changing the geometry of the Whenelt mask such that the initial direction of the ion beam in the plasma region was manipulated effectively.

January 24, 2020 Sivrice Earthquake and the response of the masonry Haci Yusuf Tas (New) mosque

  • Firat, Fatih K.;Ural, Ali;Kara, Mehmet E.
    • Earthquakes and Structures
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    • v.22 no.4
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    • pp.331-343
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    • 2022
  • Masonry structures are the most common structural systems that have been used almost all over the world from the earliest ages of history to the present day. These structural systems are often unfavorably affected by natural disasters such as earthquakes. The main reason for this is that they are built without sufficient engineering knowledge. On January 24, 2020, a severe earthquake occurred near the Sivrice District of Elazığ in eastern Turkey. According to the Turkish Directorate of Disaster and Emergency Management (AFAD), the magnitude of the earthquake was 6.8 and the focal depth 8 km. This earthquake caused damage and destruction to the masonry structures used extensively in the region. The Hacı Yusuf Taş (new) mosque in the Malatya city center, located about 64 km from the epicenter of the earthquake, was among the buildings affected by the earthquake. The mosque has smooth-cut stone walls and domes made of brick units. The main dome of the structure was severely damaged during the earthquake. In this study, information about the earthquake is first provided, and the damage to the mosque is then interpreted via photographs. In addition, two separate finite element models were produced, where the current state of mosque and solution suggestions are presented, and response spectrum analyses were carried out. According to these analyses and field observations, a buttress system to the main walls of the structure should be constructed in the direction which has little lateral rigidity.