• Title/Summary/Keyword: focal point

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Optical Implementation of Incoherent Holographic 3D Display System using Modified Triangular and Mach-Zehender Interferometer (변형된 삼각 및 마하젠더 간섭계 기반의 인코히어런트 홀로그래픽 3D 디스플레이 시스템의 광학적 구현)

  • 김승철;구정식;김은수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.4C
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    • pp.524-532
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    • 2004
  • In this paper, an incoherent holographic 3D imaging and display system based on the modified triangular and Mach-Zehnder interferometers is optically implemented and some experiments are carried out. Incoherent hologram of a 3D object is generated by using the hologram input system of modified triangular interferometer. Then this complex hologram is reconstructed by using the hologram output system of modified Mach-Zehnder interferometer in which two LCD spatial light modulators and a waveplate are inserted. From the experiment with two point sources having a depth difference of 100 mm each other, it is revealed that each point source can be independently reconstructed at its own focal position from the complex hologram, while both of the bias and conjugate image are simultaneously eliminated at the same time. And in the experiment with the real 3D object of two dices having a depth difference of 30 mm each other, it is also conformed that the bias and conjugate image can be effectively eliminated from the hologram pattern and each 3D dice can be also successfully reconstructed at its own focal position from the complex hologram. These experiment results finally suggest a possibility of implementing a new incoherent holographic 3D imaging and display system using the modified triangular and Mach-Zehender interferometers.

An Investigation on Non-Relevance Criteria for Image in Failed Image Search (이미지 검색 실패에 나타난 비적합성 평가요소 규명에 관한 연구)

  • Chung, EunKyung
    • Journal of the Korean Society for Library and Information Science
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    • v.50 no.1
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    • pp.417-435
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    • 2016
  • Relevance judgment is important in terms of improving the effectiveness of information retrieval systems, and it has been dominant for users to search and use images utilizing internet and digital technologies. However, in the field of image retrieval, there have been only a few studies in terms of identifying relevance criteria. The purpose of this study aims to identify and characterize the non-relevance criteria from the failed image searches. In order to achieve the purpose of this study, a total of 135 participants were recruited and a total of 1,452 criteria items were collected for this study. Analyses and identification on the data set found thirteen criteria such as 'topicality', 'visual content', 'accuracy', 'visual feature', 'completeness', 'appeal to user', 'focal point', 'bibliographic information', 'impression', 'posture', 'face feature', 'novelty', and 'time frame'. Among these criteria, 'visual content' and 'focal point' were introduced in this current study, while 'action' criterion identified in previous studies was not shown in this current study. When image needs and image uses are analyzed with these criteria, there are distinctive differences depending on different image needs and uses.

Reconstruction of a 3D Model using the Midpoints of Line Segments in a Single Image (한 장의 영상으로부터 선분의 중점 정보를 이용한 3차원 모델의 재구성)

  • Park Young Sup;Ryoo Seung Taek;Cho Sung Dong;Yoon Kyung Hyun
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.4
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    • pp.168-176
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    • 2005
  • We propose a method for 3-dimensionally reconstructing an object using a line that includes the midpoint information from a single image. A pre-defined polygon is used as the primitive and the recovery is processed from a single image. The 3D reconstruction is processed by mapping the correspondence point of the primitive model onto the photo. In the recent work, the reconstructions of camera parameters or error minimizing methods through iterations were used for model-based 3D reconstruction. However, we proposed a method for the 3D reconstruction of primitive that consists of the segments and the center points of the segments for the reconstruction process. This method enables the reconstruction of the primitive model to be processed using only the focal length of various camera parameters during the segment reconstruction process.

Recombinant Protein Expression and Purification of the Human HMTase MMSET/NSD2

  • Morishita, Masayo;Mevius, Damiaan;Shen, Yunpeng;Di Luccio, Eric
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.3
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    • pp.157-164
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    • 2013
  • Chromatin remodelers that include histone methyl transferases (HMTases) are becoming a focal point in cancer drug development. The NSD family of three HMTases, NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L are bona fide oncogenes found aberrantly expressed in several cancers, suggesting their potential role for novel therapeutic strategies. Several histone modifiers including HMTase have clear roles in human carcinogenesis but the extent of their functions and regulations are not well understood, especially in pathological conditions. The extents of the NSDs biological roles in normal and pathological conditions remain unclear. In particular, the substrate specificity of the NSDs remains unsettled and discrepant data has been reported. NSD2/MMSET is a focal point for therapeutic interventions against multiple myeloma and especially for t(4;14) myeloma, which is associated with a significantly worse prognosis than other biological subgroups. Multiple myeloma is the second most common hematological malignancy in the United States, after non-Hodgkin lymphoma. Herein, as a first step before entering a pipeline for protein x-ray crystallography, we cloned, recombinantly expressed and purified the catalytic SET domain of NSD2. Next, we demonstrated the catalytic activities, in vitro, of the recombinantly expressed NSD2-SET on H3K36 and H4K20, its biological targets at the chromatin.

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Geometric Modelling and Coordinate Transformation of Satellite-Based Linear Pushbroom-Type CCD Camera Images (선형 CCD카메라 영상의 기하학적 모델 수립 및 좌표 변환)

  • 신동석;이영란
    • Korean Journal of Remote Sensing
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    • v.13 no.2
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    • pp.85-98
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    • 1997
  • A geometric model of pushbroom-type linear CCD camera images is proposed in this paper. At present, this type of cameras are used for obtaining almost all kinds of high-resolution optical images from satellites. The proposed geometric model includes not only a forward transformation which is much more efficient. An inverse transformation function cannot be derived analytically in a closed form because the focal point of an image varies with time. In this paper, therefore, an iterative algorithm in which a focal point os converged to a given pixel position is proposed. Although the proposed model can be applied to any pushbroom-type linear CCD camera images, the geometric model of the high-resolution multi-spectral camera on-board KITSAT-3 is used in this paper as an example. The flight model of KITSAT-3 is in development currently and it is due to be launched late 1998.

Haptic recognition of the palm using ultrasound radiation force and its application (초음파 방사힘을 이용한 손바닥의 촉각 인식과 응용)

  • Kim, Sun Ae;Kim, Tae Yang;Lee, Yeol Eum;Lee, Soo Yeon;Jeong, Mok Kun;Kwon, Sung Jae
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.4
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    • pp.467-475
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    • 2019
  • A high-intensity ultrasound wave generates acoustic streaming and acoustic radiation forces when propagating through a medium. An acoustic radiation force generated in a three-dimensional space can produce a solid tactile sensation, delivering spatial information directly to the human skin. We placed 154 ultrasound transmit elements with a frequency of 40 kHz on a concave circular dish, and generated an acoustic radiation force at the focal point by transmitting the ultrasound wave. To feel the tactile sensation better, the transmit elements were excited by sine waves whose amplitude was modulated by a 60 Hz square wave. As an application of ultrasonic tactile sensing, a region where tactile sense is formed in the air is used as an indicator for the position of the hand. We confirmed the utility of ultrasonic tactile feedback by implementing a system that provides the number of fingers to a machine by receiving the shape of the hand at the focal point where the tactile sense is detected.

Development of Merging Algorithm between 3-D Objects and Real Image for Augmented Reality

  • Kang, Dong-Joong
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.100.5-100
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    • 2002
  • A core technology for implementation of Augmented Reality is to develop a merging algorithm between interesting 3-D objects and real images. In this paper, we present a 3-D object recognition method to decide viewing direction toward the object from camera. This process is the starting point to merge with real image and 3-D objects. Perspective projection between a camera and 3-dimentional objects defines a plane in 3-D space that is from a line in an image and the focal point of the camera. If no errors with perfect 3-D models were introduced in during image feature extraction, then model lines in 3-D space projecting onto this line in the image would exactly lie in this plane. This observa...

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The Hope of the Stroke Patients (뇌졸중환자의 희망)

  • 김이순
    • Journal of Korean Academy of Nursing
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    • v.27 no.1
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    • pp.212-227
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    • 1997
  • Cerebrovascular diseases in Korea is an important health problem since mortality and mobidity have been increased rapidly. It marked the 2nd cause of specific death rates in 1993. The stroke causes physical function disorder due to hemiparalysis and emotional disorder, and stroke patients experience helplessness, powerlessness. sense of alienation and loss of hope. These feelings make the rehabilitation difficult because they lose the will of life. The subjects of the study were seven citizens who live in Pusan, are over 50 years old and belong to low income-level. The data were collected from Jan. to Sep. 1995. The researcher as a caregiver and volunteer made confidence of them and asked for their agreement on the purpose of the study. The subjects expressed their experience as openheartedly as possible. The analysis of the data was made through the phenomenological analytic method suggested by Giorgi, which is as follows ; as an unit of description which include the subject' expressions and the researcher's observation, it is examined the theme that express the hope experience with the subject's language(underlining), and the focal meanings are identified. The focal meaning is the crystalization of the theme, which is written in the language of the researcher. After intergrating the focal meaning and make the situated structural description as the meaning of the hope experience identified on each subject's point. After intergrating the situated structural description and make the general structural description as the meaning of the hope experience identified on total subject's point then the systemizing of the structure of the hope experienced phenomena and the flowing of the conciousness was researched. The conclusions of this study was as follows : The ten sources of hope which the subjects experienced were sorted as under 〈mutual relations to others : spouse, children, relatives, fellow believer. health professioner. associate patient group〉, 〈spiritual dependence〉. 〈recovery of physical function〉. 〈rumination of the past life〉, 〈expectation of the future〉. 〈economic power〉, 〈belief〉, 〈ability〉. 〈spontaneous participation〉 and 〈recovery of roles〉. Their hope was spoken out by the following two kinds of linguistics. First. the hope was expressed in the affirmative expression as follows : 〈 to be dependable〉, 〈to make efforts〉, 〈to keep under control〉, 〈to desire〉, 〈to be pleasant〉, 〈to be peaceful〉, 〈to be grateful〉, 〈to give help〉, 〈self-confidence. Courage〉, 〈to be happy〉, 〈to satisfy oneself〉, 〈to share with others〉, 〈to understand〉 and 〈to be affected, be impressed〉 Second, the hope was expressed in the negative on pression as under : 〈to be distressed〉, 〈to be uneasy〉, 〈to be sorry, be unsatisfied〉 〈despair〉, 〈to abandon〉, 〈to be fearful〉, 〈to suffer〉, 〈to bear a burden〉 〈to be confused〉, 〈to be solitary〉, 〈chest trouble〉, 〈to feel heavy〉 〈grief〉, 〈to be daunted〉, 〈to get angry〉, 〈to be uncomfortable〉, 〈to have something regretable〉 and 〈to feel guilty〉. And their hope was expressed by the following four behavioral expressions : 〈physical sphere〉, 〈psychological sphere〉, 〈social support sphere〉 and 〈spiritual sphere〉. The reaction patterns of their hope experience appeared in the following 4 coping method : 〈conquest type〉, 〈dependence type〉, 〈adaptation type〉 and 〈fate type〉. Finally, in the hope structure the sense of certainty don't always coexict with the sense of uncertainty, When the stroke patients try to search for the best quality of life, the senses of certainty and uncertainty make a continual cyclic system in the hope structure.

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An Ultrastructural Study on the Effect of Exogenous $Ca^{2+}$ Stimulation to Ischemic Myocardium during Post-ischemic Reperfusion (재관류시 외인성 칼슘 자극이 허혈 심근에 미치는 영향에 대한 전자현미경적 연구)

  • Kim, Ho-Dirk;Chun, Sang-Bae;Rah, Bong-Jin
    • Applied Microscopy
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    • v.21 no.1
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    • pp.1-20
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    • 1991
  • The effects of exogenous $Ca^{2+}$ stimulation on the post-ischemic myocardial cells were studied using isolated Langendorff-perfused guinea pig hearts. At the starting point of reperfusion, Tyrode solutions, each containing 2.0mM, 4.0mM and 8.0mM $CaCl_2$ respectively, were administered for 2 minutes apart by descending, ascending, or by combined sequences followed by standard Tyrode solution containing 1.0mM $CaCl_2$. The minutes of global ischemia produced reversible but moderate to severe degree of myocardial ultrastructrual changes including focal destruction of sarcolemma, loss of nuclear matrix, clumping and margination of chromatins, mitochondrial swelling, destruction of mitochondrial cristae, shortening of sarcomeres, focal loss of myofibrils, and separation of cell junctions. In spite of reperfusion, the ultrastructure was more severely damaged and irreversible changes such as intracellular fluid accumulation, contracted sarcomeres, mitochondrial destruction, disruption of sarcolemma, loss of nuclear matrix, and separation of cell junction were observed in a large number of cells. In contrast, Tyrode-perfused $Ca^{2+}$-stimulated myocardial cells showed relatively well preserved ultrastucture, except slight changes including focal mitochondrial swelling, widening of T-tubule, and widening of cell junctions, especially at fasciae adherentes. The post-ischemic $Ca^{2+}$-stimulated reperfused myocardial cells produced focal changes such as mitochondrial destruction, disintegration of sarcolemma, widening of T-tubule, and intracellular fluid accumulation with slight variation in degree of changes by the method of $Ca^{2+}$ administration sequence. However, in a large number of the myocardial cells, chromatins were redistributed relatively evenly in the nuclear matrix, mitochondrial cristae were tightly packed, and a considerable number of intramitochondrial granules and glycogen granules reap-pealed. These results indicate that exogenous $Ca^{2+}$ stimulation in the initial period of reperfusion may be beneficial to salvage or to reduce the post-ischemic myocardium from further deleterious changes, and that the beneficial effects may be derived from the reserves of the function of the intracellular $Ca^{2+}$ regulating organelles and/or from the responsiveness of contractile apparatus to $Ca^{2+}$ stimulation.

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Clinical Implications of Focal Mineral Deposition in the Globus Pallidus on CT and Quantitative Susceptibility Mapping of MRI

  • Hyojin Kim;Jinhee Jang;Junghwa Kang;Seungun Jang;Yoonho Nam;Yangsean Choi;Na-young Shin;Kook-Jin Ahn;Bum-soo Kim
    • Korean Journal of Radiology
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    • v.23 no.7
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    • pp.742-751
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    • 2022
  • Objective: To assess focal mineral deposition in the globus pallidus (GP) by CT and quantitative susceptibility mapping (QSM) of MRI scans and evaluate its clinical significance, particularly cerebrovascular degeneration. Materials and Methods: This study included 105 patients (66.1 ± 13.7 years; 40 male and 65 female) who underwent both CT and MRI with available QSM data between January 2017 and December 2019. The presence of focal mineral deposition in the GP on QSM (GPQSM) and CT (GPCT) was assessed visually using a three-point scale. Cerebrovascular risk factors and small vessel disease (SVD) imaging markers were also assessed. The clinical and radiological findings were compared between the different grades of GPQSM and GPCT. The relationship between GP grades and cerebrovascular risk factors and SVD imaging markers was assessed using univariable and multivariable linear regression analyses. Results: GPCT and GPQSM were significantly associated (p < 0.001) but were not identical. Higher GPCT and GPQSM grades showed smaller gray matter (p = 0.030 and p = 0.025, respectively) and white matter (p = 0.013 and p = 0.019, respectively) volumes, as well as larger GP volumes (p < 0.001 for both). Among SVD markers, white matter hyperintensity was significantly associated with GPCT (p = 0.006) and brain atrophy was significantly associated with GPQSM (p = 0.032) in at univariable analysis. In multivariable analysis, the normalized volume of the GP was independently positively associated with GPCT (p < 0.001) and GPQSM (p = 0.002), while the normalized volume of the GM was independently negatively associated with GPCT (p = 0.040) and GPQSM (p = 0.035). Conclusion: Focal mineral deposition in the GP on CT and QSM might be a potential imaging marker of cerebral vascular degeneration. Both were associated with increased GP volume.