• Title/Summary/Keyword: Focal

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INTEGRATED RAY TRACING MODEL FOR END-TO-END PERFORMANCE VERIFICATION OF AMON-RA INSTRUMENT (AMON-RA 광학계를 활용한 통합적 광선 추적 기법의 지구 반사율 측정 성능 검증)

  • Lee, Jae-Min;Park, Won-Hyun;Ham, Sun-Jeong;Yi, Hyun-Su;Yoon, Jee-Yeon;Kim, Sug-Whan;Choi, Ki-Hyuk;Kim, Zeen-Chul;Lockwood, Mike
    • Journal of Astronomy and Space Sciences
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    • v.24 no.1
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    • pp.69-78
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    • 2007
  • The international EARTHSHINE mission is to measure 1% anomaly of the Earth global albedo and total solar irradiance using Amon-Ra instrument around Lagrange point 1. We developed a new ray truing based integrated end-to-end simulation tool that overcomes the shortcomings of the existing end-to-end performance simulation techniques. We then studied the in-orbit radiometric performance of the breadboard Anon-Ra visible channel optical system. The TSI variation and the Earth albedo anomaly, reported elsewhere, were used as the key input variables in the simulation. The output flux at the instrument focal plane confirms that the integrated ray tracing based end-to-end science simulation delivers the correct level of incident power to the Amon-Ra instrument well within the required measurement error budget of better than ${\pm}0.28%$. Using the global angular distribution model (ADM), the incident flux is then used to estimate the Earth global albedo and the TSI variation, confirming the validity of the primary science cases at the L1 halo orbit. These results imply that the integrated end-to-end ray tracing technique, reported here, can serve as an effective and powerful building block of the on-line science analysis tool in support of the international EARTHSHINE mission currently being developed.

Venous Congestion in Cerebral Hyperperfusion Syndrome: A Case Report (뇌과관류증후군에서 보일 수 있는 정맥울혈 1례)

  • Bong, Jeong Bin;Kang, Hyun Goo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.8
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    • pp.84-87
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    • 2017
  • Cerebral hyperperfusion syndrome (CHS) is a rare complication that can occur when conducting stent insertion or endarterectomy in patients with carotid artery stenosis and is known to be caused by various mechanisms when the blood volume abruptly increases. The main clinical symptoms are unilateral headache, hypertension, seizure, and focal neurologic deficit. Subarachnoid hemorrhage and parenchymal hemorrhage may lead to permanent impairment or death in severe cases. CHS can be predicted by using transcranial Doppler, perfusion magnetic resonance imaging, and single photon emission computed tomography. In our case report, a patient developed CHS subsequent to significant venous congestion caused by carotid artery stent insertion. The patient had preexisting, symptomatic bilateral carotid artery stenosis. Venous congestion occurs when the direction of blood flow changes because of increased blood volume in patients with well-developed collateral vessels. We believe that CHS can be predicted from this finding. This study reports the possibility that CHS could be confirmed by cerebral angiography after insertion of the internal carotid stent.

Analysis of cognitive factors affecting stroke patient's activity of daily living performance -Using the computerized neurocognitive function test- (뇌졸중 환자의 일상 활동 수행에 영향을 미치는 인지요인 분석 -전산화 신경인지기능검사 중심으로-)

  • Kim, Ji-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.12
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    • pp.5715-5721
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    • 2011
  • This research analyzed the cognitive factors affecting stroke patient's activity of daily living performance and suggests the approaches which can contribute to the effective activity of daily living performance in the rehabilitation treatment of stroke patients. In this study, Seoul Computerized NeuroCognitive Function Test (SCNT) and MBI have been performed for 21 patients under extensive rehabilitation treatments, hospitalized in the rehabilitation clinic of A hospital after being diagnosed as a stroke caused by cerebrovascular disorders. To assess the effectiveness of the cognitive factors which affect the stroke patient's activity of daily living performance, activity of daily living performance values were set as dependent variables and 10 cognitive factors were included in the model to carry out analysis of the multiple regression analysis. The results show that stroke patient's activity of daily living performance have statistically significant correlations with divided attention, motor control and selectivir attention. In addition, cognitive factors explained 69.8% of the stroke patient's activity of daily living performance. Consequently, if divided attention and motor control are considered as a focal point of training in the rehabilitation treatment of stroke patients, we can effectively promote the improvement of the activity of daily living performanceroutine activities.

Study of the Effects of Supplier Monitoring on Shop floor Productivity (공급사 모니터링이 현장생산성에 미치는 영향에 관한 연구)

  • Cho, BooYun;Kang, Gi-Choon;Hyun, MinCheol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.12
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    • pp.7025-7039
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    • 2014
  • Focal companies (hereafter called buyers) adopt outsourcing practices from a supply chain management strategy to be competitive. Buyers face the bridge transfer after outsourcing contracts, and the monitoring practices would be the only control mechanism left to prevent losing control over the suppliers. This study suggests the set of monitoring practices (i.e., capability, activity and outcome monitoring) as the independent variables to enhance the buyer-supplier collaboration and supplier's performance. In addition the buyer's efforts of monitoring are assumed to influence the buyer's shop floor productivity mediated by the supplier's performance and buyer-supplier collaboration. The results showed that the monitoring practices are meaningful antecedents to the supplier's performance and buyer-supplier collaboration, which fully mediates between the monitoring practices and buyer's shop floor productivity. The mediating role of the buyer-supplier collaboration between activity monitoring and shop floor productive has been rejected, because the negative effect of activity monitoring on buyer-supplier collaboration conflicts with the positive impact of buyer-supplier collaboration on shop floor productive. The theoretical contribution and managerial implications with limitations have been discussed.

Analysis of the Result and Merit of Computed Tomography Guided Percutaneous Needle Aspiration Biopsy of Focal Lung Lesion (CT 유도하 국소적 폐질환의 경피적 흡입생검의 장점과 결과 분석)

  • Chang, You-Song;Cho, Kil-Ho;Byun, Woo-Mock;Hwang, Mi-Soo;Park, Bok-Hwan
    • Journal of Yeungnam Medical Science
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    • v.10 no.1
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    • pp.127-134
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    • 1993
  • Percutaneous needle biopsy of pulmonary lesion with use of fluoroscopic guidance is well established as a diagnostic tool but limited by the small size and inaccessibility of certain lesions. However, percutaneous needle biopsy has been used increasingly in relation to advance and the safty of smaller biopsy needle and new imaging modalities such as ultrasound and CT. CT, because of its characteristics of high resolution, allows tissue sampling with considerable safety from area that heretofore could not be visualized under fluoroscopy. The authors summarized 44 pulmonary lesions that underwent CT-guided transthoracic biopsy with fine-needle over a 14 month period and analyzed the sensitivity of PTNB. CT-guided PTNB was done with 20 gauge or 22 gauge Westcott biopoy needle(Manan medical products, USA). A diagnosis was made in 27 of 44 cases(61%) including malignany in 19 of 24 cases and benignancy in 8 of 20 cases. The pulmonary mass lesions were located at the peripheral zone of the lung field in 33 cases and at the central zone in 11 cases. Complications were observed in 2 cases which were pneumothorax and hemoptysis each but specific therapy was not required. The sensitivity of PTNB by one session was 61%(27/44). The sensitivity of malignancy was 79%(19/24) and benignancy was 40%(8/20). These results suggest the usefulness of PTNB using fine needles be increased in earlier diagnosis and improved staging of pulmonary nodular lesions without significant complications.

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Signal change in hippocampus and current source of spikes in Panayiotopoulos syndrome

  • Yeom, Jung-Sook;Kim, Young-Soo;Park, Ji-Sook;Seo, Ji-Hyun;Park, Eun-Sil;Lim, Jae-Young;Park, Chan-Hoo;Woo, Hyang-Ok;Youn, Hee-Shang;Kwon, Oh-Young
    • Clinical and Experimental Pediatrics
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    • v.55 no.2
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    • pp.63-67
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    • 2012
  • A 4-year-old girl with Panayiotopoulos syndrome presented with a history of 4 prolonged autonomic seizures. The clinical features of her seizures included, in order of occurrence, blank staring, pallor, vomiting, hemi-clonic movement on the right side, and unresponsiveness. A brain magnetic resonance imaging (MRI) showed a slightly high $T_2$ signal in the left hippocampus. Interictal electoencephalogram revealed spikes in the occipital area of the left hemisphere. We analyzed the current-source distribution of the spikes to examine the relationship between the current source and the high $T_2$ signal. The current source of the occipital spikes was not only distributed in the occipital area of both cerebral hemispheres, but also extended to the posterior temporal area of the left hemisphere. These findings suggest that the left temporal lobe may be one of the hyperexcitable areas and form part of the epileptogenic area in this patient. We hypothesized that the high $T_2$ signal in the left hippocampus of our patient may not have been an incidental lesion, but instead may be related to the underlying electroclinical diagnosis of Panayiotopoulos syndrome, and particularly seizure. This notion is important because an abnormal $T_2$ signal in the hippocampus may represent an acute stage of hippocampal injury, although there is no previous report of hippocampal pathology in Panayiotopoulos syndrome. Therefore, long-term observation and serial follow-up MRIs may be needed to confirm the clinical significance of the $T_2$ signal change in the hippocampus of this patient.

A Clinical Analysis of Chronic Subdural Hematoma according to Age Factor (연령에 따른 만성 뇌경막하 혈종의 임상적 분석)

  • Jeong, Jae Eun;Kim, Gook Ki;Park, Jong Tae;Lim, Young Jin;Kim, Tae Sung;Rhee, Bong Arm;Leem, Won
    • Journal of Korean Neurosurgical Society
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    • v.29 no.6
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    • pp.748-753
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    • 2000
  • Objectives : A 10-year retrospective clinical study was undertaken to determine the differences between two groups according to age at presentation(group A, under 50 ; B, over 50). Methods : We analyzed 468 cases with chronic subdural hematoma admitted to the department of neurosurgery in our hospital from January 1987 to December 1996. The patients were divided into two groups according to age at presentation(group A, under 50 ; B, over 50). Results : 1) The number of group A was 126 cases(26.9%) and that of group B was 342 cases(73.1%), respectively. Males were more frequently involved than females in each group. 2) There noted a history of head trauma in 88.9% of group A and 92.4% of group B. Forty-nine patients(38.9%) of group A and 103 cases(30.1%) of group B revealed a history of alcoholism. 3) Group A patients presented with symptoms of increased intracranial pressure such as headache(75.% ), nausea and vomiting(68.0%). However, Group B patients had more frequent mental changes(84.0%) and focal neurological deficits such as hemiparesis(76.5%). 4) Onset of symptom and its duration was shorter in group A than group B. 5) Six patients among 441 cases(1.4%) treated with burr hole drainage and two patients of 27 cases(5.4%) with craniotomy died, and all of these were group B patients. The two cases among six patients with burr hole drainage developed huge intracerebral hemorrhage and brain stem hemorrhage, respectively. Conclusion : In treating patients with chronic subdural hematoma, distinguishing between two age groups is quite helpful to determine treatment strategies.

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Metabolic Changes in Pericontusional Edematous Areas in Mild Head Injury Evaluated by Proton MRS (경도 두부외상 환자에서 뇌좌상주위 부종영역에서의 자기공명분광법을 이용한 대사변화)

  • Hong, Sang-Su;Son, Byung-Chul;Cho, Byung Gil;Kim, Euy-Nyeng;Kim, Bum-Soo;Park, Chun-Kum;Choe, Bo-Young;Kim, Moon-Chan;Kang, Joon-Ki
    • Journal of Korean Neurosurgical Society
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    • v.29 no.9
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    • pp.1233-1237
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    • 2000
  • Objectives : In order to evaluate the metabolic changes associated with pericontusional edematous area in mild head injury, proton magnetic resonance spectroscopy(1H-MRS) was performed in mild head injury patients (initial GCS score 13-15) with focal brain contusion. Methods : Seven head injury patients with initial GCS 13-15(3 males and 4 females : age range 15-65 years, mean age 33 years) have underwent 1H-MRS evaluations. The patients were examined within 7 days after injury(n=7) and 2 months after injury(n=5). The region of interest(ROI) was selected in the edematous area adjacent to traumatic brain contusion upon T2-weighted MR images and a corresponding region of the contralateral hemisphere (ROC, region of contralateral corresponding hemisphere) was examined as well. The metabolic ratios of NAA/Cr and lactate/Cr were compared between ROIs, ROCs and control values. Results : In initial NAA/Cr ratios, the values of ROIs were significantly lower than those of the controls(p=0.009), but there was no difference either between ROIs and ROCs(p=0.410) or between ROCs of patients and the control (p=0.199). In lactate/Cr ratios, the ROIs in all seven patients and the ROCs in two showed increased lactate signals. The lactate/Cr ratios of the ROIs were significantly elevated as compared to those of the ROCs(p=0.02) and the control(p=0.015). In two months follow-up, lactate signals were absent or significantly reduced(p=0.015). In no patients, clinical or radiological deterioration has been observed. Conclusion : Our 1H-MRS results demonstrate that there are significant ischemic changes in pericontusional edematous areas as indicated by elevated lactate signals in the patients with mild head injury. But there were no consistent neural loss or dysfunction in these area. There findings suggest that pericontusional edematous areas can be vulnerable to secondary brain insults even in the patients with mild head injury.

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The Impact of Cause Diversity and Fit on Purchase Intention According to Choice of Cause (공익 선택에 따라 공익 다양성과 적합성이 구매의도에 미치는 영향)

  • Shen, Xiangdong;Bae, Byungryul
    • The Journal of Industrial Distribution & Business
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    • v.10 no.3
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    • pp.35-44
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    • 2019
  • Purpose - The purpose of this study is to empirically investigate the effect of choice of cause on the purchase intention by dividing it into the situation selected by the consumer and the company. This study also examines the moderating effect of cause options diversity and company-cause fit on the relationship between choice of cause and purchase intention. This will provide the theoretical information necessary to gain an in-depth understanding of the consumer's intention to purchase the cause-related marketing campaign, and in practice, it is expected that companies will be able to obtain useful information for effective planning and execution of the cause-related marketing campaign. Research design, date, and methodology - This study's survey was carried out on the college students of university located in Shandong, China. It was from November 4-11, 2018, and a total of 440 questionnaires were distributed, with 424 collected. Of them, effective questionnaires used in the final study were a total of 400 except 24 that couldn't be used. In this study, empirical analysis was done with frequency analysis, reliability analysis, analysis of variance and simple effect analysis by using Statistics Package SPSS 20.0. Results - The results are reported below: first of all, in the cause-related campaign consumers are more willing to buy the products when they are allowed to choice the focal cause of charity than when the company selects the cause of charity. Furthermore, the positive effect of allowing consumers to choice the cause of charity (vs. company choice) on purchase intentions is greater for high cause diversity to select. Finally, the positive effect of allowing consumers to choice the cause of charity (vs. company choice) on purchase intentions is greater when perceived fit between the company and the cause charity is low. Conclusions - This study extends the scope of the consumer perspective from consumer purchase intention research to the choice of cause in the cause-related marketing. When consumers select the cause, it would be better to provide the cause charity in diversifying selection and provide options for low fit between company and cause charity.

A Study on the Integrated System Implementation of Close Range Digital Photogrammetry Procedures (근거리 수치사진측량 과정의 단일 통합환경 구축에 관한 연구)

  • Yeu, Bock-Mo;Lee, Suk-Kun;Choi, Song-Wook;Kim, Eui-Myoung
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.1 s.13
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    • pp.53-63
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    • 1999
  • For the close range digital photogrammetry, multi-step procedures should be embodied in an integrated system. However, it is hard to construct an Integrated system through conventional procedural processing. Using Object Oriented Programming(OOP), photogrammetric processings can be classified with corresponding subjects and it is easy to construct an integrated system lot digital photogrammetry as well as to add the newly developed classes. In this study, the equation of 3-dimensional mathematic model is developed to make an immediate calibration of the CCD camera, the focus distance of which varies according to the distance of the object. Classes for the input and output of images are also generated to carry out the close range digital photogrammetric procedures by OOP. Image matching, coordinate transformation, dirct linear transformation and bundle adjustment are performed by producing classes corresponding to each part of data processing. The bundle adjustment, which adds the principle coordinate and focal length term to the non-photogrammetric CCD camera, is found to increase usability of the CCD camera and the accuracy of object positioning. In conclusion, classes and their hierarchies in the digital photogrammetry are designed to manage multi-step procedures using OOP and close range digital photogrammetric process is implemented using CCD camera in an integrated System.

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