• Title/Summary/Keyword: CBF

Search Result 292, Processing Time 0.023 seconds

Fast Mode Decision Algorithm for Intra Prediction in HEVC using transform coefficients and coded block flag (변환계수와 CBF 를 이용한 HEVC 고속 화면 내 예측)

  • Kim, Nam-Uk;Lee, Yung-Lyul
    • Proceedings of the Korean Society of Broadcast Engineers Conference
    • /
    • 2015.11a
    • /
    • pp.145-146
    • /
    • 2015
  • HEVC(High Efficient Video Coding)는 H.264/AVC 대비 하여 50% 정도의 높은 압축률을 보이지만 인코더의 복잡도가 크게 증가하였다. 이러한 높은 복잡도로 인한 실사용에 있어서의 문제를 줄이기 위하여 본 논문에서는 변환계수의 분포와 cbf(coded block flag)를 이용하여 예측블록의 크기를 빠르게 결정짓는 방법을 제안한다. 제안된 방법은 HM16.0 대비 42%의 부호화 속도를 향상시켰으며 1.9%의 성능 감소를 갖는다.

  • PDF

Mechanism of Mokhyangjoki-san Extract on the Improvement in Cerebral Blood Flow in Ischemic Rats (목향조기산(木香調氣散) 추출물이 뇌허혈 흰쥐의 뇌혈류개선에 미치는 작용기전)

  • Shim, Ik-Hyun;Choi, Chan-Hun;Kim, Yeong-Mok;Yoon, Young-Jeoi;Jeong, Hyun-Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.25 no.5
    • /
    • pp.807-815
    • /
    • 2011
  • This study was designed to investigate the effects of Mokhyangjoki-san extract (MJS) on the improvement in cerebral blood flow (rCBF) in cerebral ischemic rats, and further to determine cytokines production (IL-1${\beta}$, TNF-${\alpha}$, IL-10, TGF-${\beta}$) of MJS. The results in cerebral ischemic rats were as follows ; The rCBF was significantly and stably increased by MJS (10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. In cytokine production in serum from femoral arterial blood 1 hr after middle cerebral arterial occlusion, MJS significantly decreased IL-1${\beta}$ and TNF-${\alpha}$ production, and increased IL-10 production compared with control group. In cytokine production in serum from femoral arterial blood 1 hr after reperfusion, MJS significantly decreased IL-1${\beta}$ and TNF-${\alpha}$ production compared with control group. IL-10 and TGF-${\beta}$1 production in MJS group were significantly increased compared with control group. These results suggested that MJS significantly and stably increased rCBF by inhibiting the production IL-1${\beta}$ and TNF-${\alpha}$, and accelerating that of IL-10 and TGF-${\beta}$. The result in nerve cells was as follows ; MJS significantly inhibited lactate dehydrogenase activity in vitro in a dose-dependent manner. This result suggested that MJS prevented the neuronal death.

Neurological Improvement after Cranioplasty in Patients with Surgical Bony Defects : The Usefulness of Acetazolamide Activated $^{99m}Tc-HMPAO$ SPECT

  • Seo, Won-Duck;Kim, Young-Don;Hong, Dae-Young;Kim, Dae-Hyun;Choi, Gi-Hwan;Yeo, Hyung-Tae
    • Journal of Korean Neurosurgical Society
    • /
    • v.40 no.6
    • /
    • pp.434-440
    • /
    • 2006
  • Objective : The purpose of this study is to examine the influence of cranioplasty on dynamics of cerebral blood flow[CBF] and cerebrovascular reserve capacity[CVRC], and to investigate the usefulness of single photon emission computed tomography [SPECT] as a prognostic factor for neurological improvement after cranioplasty. Methods : Between March 2003 and December 2005, a prospective study was performed on 24 patients who had undergone total 25 cranioplasty operations. Cerebral blood flow velocities in the middle cerebral artery[MCA] and internal carotid artery[ICA] were obtained by transcranial Doppler ultrasonography[TCD]. The CVRC was assessed by SPECT in the natural state and after stimulation with 1g of acetazolamide. Neurological improvement after cranioplasty was compared between patients who showed hyperactivity to acetazolamide-activated SPECT [Group 1, n=7] and hypoactivity to acetazolamide-activated SPECT [Group 2, n=17]. These measurements were obtained two weeks prior to and two weeks after cranioplasty. Results : The blood flow velocities at the opposite site to the cranioplasty as well as at the cranioplasty site were significantly increased [P<0.05]. Compared with Group 2, there was significant increase in CBF and neurological improvement after cranioplasty in Group 1. Conclusion : Among patients with surgical bony defects, the patients who had normal reactivity of the CVRC showed a significant increase in CBF and neurological improvement after cranioplasty. The authors suggest that CVRC measurement prior to surgery may be an important prognostic factor for neurological improvement after cranioplasty.

Zinc status and growth of Korean infants fed human milk, casein-based, or soy-based formula: three-year longitudinal study

  • Han, Young-Hee;Yon, Mi-Yong;Han, Heon-Seok;Johnston, Kelley E.;Tamura, Tsunenobu;Hyun, Tai-Sun
    • Nutrition Research and Practice
    • /
    • v.5 no.1
    • /
    • pp.46-51
    • /
    • 2011
  • To evaluate the effect of feeding methods on growth and zinc nutritional status of infants early in life, we monitored from birth to 36 months in 51 infants who were exclusively fed human milk (HM, n=20), casein-based formula (CBF, n=12), or soy-based formula (SBF, n=19) during the first five months of life. Zinc status was assessed by analyzing serum zinc concentrations and zinc intakes. Zinc contents in HM and formulas were measured. Zinc intake was estimated by weighing infants before and after feeding in the HM group and by collecting formula-intake records in the CBF and SBF groups. After solid foods were introduced, all foods consumed were also included to estimate zinc intake. The growth of infants in all groups was similar to that established for normal Korean infants. Human milk zinc concentrations declined as lactation progressed. Zinc concentrations in all formulas tested in this study were higher than HM and were also higher than those claimed by the manufacturers. During the first twelve months, mean serum zinc concentrations of infants were similar in all groups, although infants in the HM group consistently had the lowest zinc intake among the groups, and the overall zinc intake in infants fed SBF was highest. This finding could be explained by the difference zinc bioavailability of HM and formulas. In conclusion, infants fed HM, CBF or SBF has normal growth up to three years of age, although HM contained the lowest zinc concentration followed by CBF, then SBF.

Statistical Analysis of rCBF Positron Emission Tomography Images for the Functional Mapping of Human Memory

  • Lee, J.S.;Lee, D.S.;Park, K.S.;Kwark, C.;Lee, S.K.;Chung, J.K.;Lee, M.C.;Koh, C.S.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1997 no.05
    • /
    • pp.92-94
    • /
    • 1997
  • By measuring the increase of regional cerebral blood flow (rCBF) during the activation tasks, we can describe the brain regions that participate in certain specific functions. In this study, we composed the functional maps of verbal and nonverbal memory by performing the rCBF positron emission tomography (PET) activation studies and analyzing the differences between control and each activation state. Successive four tasks, which consist of one control state and three different activation tasks, were performed on 6 normal volunteers. All images were spatially normalized on standard atlas and the differences between control and activation states were statistically analyzed. The verbal memory activated predominantly left-sided structures, especially left superior temporal cortex, and the nonverbal short-term memory activated the right frontal cortex. Also, some regions ,where is thought to be related with short-term memory system, such as cingulate gyrus and hippocampus were activated. We conclude that biological validity of the brain regions for verbal and nonverbal memory could be tested using rCBF PET imaging technique and statistical analysis.

  • PDF

Fast CU Decision Algorithm using the Initial CU Size Estimation and PU modes' RD Cost (초기 CU 크기 예측과 PU 모드 예측 비용을 이용한 고속 CU 결정 알고리즘)

  • Yoo, Hyang-Mi;Shin, Soo-Yeon;Suh, Jae-Won
    • Journal of Broadcast Engineering
    • /
    • v.19 no.3
    • /
    • pp.405-414
    • /
    • 2014
  • High Efficiency Video Coding(HEVC) obtains high compression ratio by applying recursive quad-tree structured coding unit(CU). However, this recursive quad-tree structure brings very high computational complexity to HEVC encoder. In this paper, we present fast CU decision algorithm in recursive quad-tree structure. The proposed algorithm estimates initial CU size before CTU encoding and checks the proposed condition using Coded Block Flag(CBF) and Rate-distortion cost to achieve the fast encoding time saving. And, intra mode estimation is also possible to be skipped using the CBF values acquired during the inter PU mode estimations. Experiment results shows that the proposed algorithm saved about 49.91% and 37.97% of encoding time according to the weighting condition.

Pseudo Continuous Arterial Spin Labeling MR Imaging of Status Epilepticus (간질중첩증의 동맥 스핀 라벨링 자기공명영상)

  • Yi, Min-Kyung;Choi, Seung-Hong;Jung, Keun-Hwa;Yoon, Tae-Jin;Kim, Ji-Hoon;Sohn, Chul-Ho;Chang, Kee-Hyun
    • Investigative Magnetic Resonance Imaging
    • /
    • v.16 no.2
    • /
    • pp.142-151
    • /
    • 2012
  • Purpose : The purpose of this study was to describe arterial spin labeling MR image findings of status epilepticus. Materials and Methods: A retrospective chart review within our institute revealed six patients who had been clinically diagnosed as status epilepticus and had also undergone MR imaging that included ASL in addition to routine sequences. Results: Six patients with status epilepticus were studied by conventional MR and arterial spin labeling imaging. All patients showed increased regional CBF correlating with EEG pathology. Notably, in two patients, conventional MRI and DWI showed no abnormal findings whereas pCASL demonstrated regional increased CBF in both patients. Conclusion: Arterial spin labeling might offer additional diagnostic capabilities in the evaluation of patients with status epilepticus.

Mechanism of Jaeumgenby-tang adding Aurantii FructusㆍGastrodae Rhizoma on the Improvement and Changes of Cerebral Hemodynamics (자음건비탕가지각ㆍ천마가 뇌혈류역학 변동에 미치는 작용기전)

  • Im Gwang Mo;Park Choul Hoon;Jeong Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.17 no.2
    • /
    • pp.416-422
    • /
    • 2003
  • Jaeumgenby-tang(JGT) have been used in oriental medicine for many centuries as a therapeutic agent of vertigo caused by deficiency of qi(氣) and blood(血). Effect of Aurantii Fructus(AF) take off the phlegm by promoting the circulation of qi, Gastrodae Rhizoma(GR) has effects treating for headache, vertigo by calming the liver and suppressing hyperactivity of the liver-yang(陽). And, We reported that JGT adding AFㆍGR extract(JGTAG) was significantly increased regional cerebral blood f1ow(rCBF) by dilating pial arterial diameter(PAD). Therefor we designed to investigate whether JGTAG is mediated by adrenergic β-receptor, cyclooxygenase or guanylate cyclase in normal rats. The changes of rCBF and mean arterial blood pressure(MABP) were determinated by laser-doppler flowmetry(LDF), and the change of PAD was determinated by video microscope and width analyzer. The results were as follows in normal rats; Pretreatment with propranolol(1mg/kg, i.v.) was significantly inhibited JGTAG induced increase of rCBF, PAD and MABP, and pretreatment with indomethacin(1 mg/kg, i.v.) was significantly inhibited too. But pretreatment with methylene blue(10μg/kg, i.v.) were accelerated JGTAG induced increase of rCBF and MABP, but pretreatment with methylene blue was inhibited JGTAG induced increase of PAD. This results suggest that the mechanism of JGTAG is mediated by adrenergic β-receptor and cyclooxygenase.

The Nuclear Medical Study on the Effect of ST36 Electroacupuncture on Cerebral Blood Flow (족삼리(足三里) 전침자극(電針刺戟)이 뇌혈류(腦血流)에 미치는 영향(影響)에 관한 핵의학적(核醫學的) 고찰(考察))

  • Kim, Il-du;Oh, Hei-hong;Song, Ho-chun;Bom, Hee-seung;Byun, Jae-yung;Ahn, Soo-gi
    • Journal of Acupuncture Research
    • /
    • v.18 no.2
    • /
    • pp.18-26
    • /
    • 2001
  • Purpose : To evaluate the effects of electroacupuncture on regional cerebral blood flow (rCBF) at acupoints suggested by oriental medicine to be related to the treatment of cerebrovascuiar diseases. Materials and Methods : Rest/electroaeupuncture-stimulation Tc-99m ECD brain SPECT using a same-dose subtraction method was performed on 5 normal male volunteers (age range from 27 to 30 years) using electroacupuncture at acupoint, ST 36. In the control study, needle location was chosen on a non-meridian focus 1cm posterior to the right fibular head. All images were spatially normalized and the differences between rest and acupuncture stimulation were statistically analyzed using SPM$^{(R)}$ for Windows$^{(R)}$. Results : Electroacupuncture applied at ST36 increased rCBF in the left hemisphere, that is, the left parietal lobe(angular gyrus), the left temporal lobe, the left inferior frontal lobe around rectus gyrus and the left cerebellar hemisphere, a part of the left inferior frontal lobe. In the control stimulation, no significant rCBF increase was observed. Conclusion : The results demonstrate that electroacupuncture increases rCBF in the contralateral cerebral hemisphere.

  • PDF

Effects of FOENICULI FRUCTUS on the Regional Cerebral Blood Flow and Mean Arterial Blood Pressure in Rats (소회향이 흰쥐의 국소뇌혈류량 및 평균혈압에 미치는 영향)

  • Kim, Nam-Soon;Jeong, Hyun-Woo;Kang, Sung-Yong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.21 no.3
    • /
    • pp.652-657
    • /
    • 2007
  • This experimental study was designed to investigate the effects of FOENICULI FRUCTUS freeze dry powder (FF) on the change of cerebral hemodynamics [regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP)] in normal and further to determine the mechanism of action of FF. The results in normal rats were as follows ; FF significantly increased rCBF in a dose-dependent, but decreased MABP, This results were suggested that FF significantly increased rCBF by dilating PAD. The FF-induced increase in rCBF was significantly inhibited by pretreatment with 1H[1,2,4]oxadizolo[4,3-a]quinoxalin-1-one (ODQ, 10 ${\mu}$g/kg, i.p.), an inhibitor of guanylate cyclase and indomethacin (IDN, 1 mg/kg, i.p.), an inhibitor of cyclooxygenase and propranolol (PPN, 3 mg/kg, i.p.), a blocker of adrenalic f receptor and Lu-Nitro-L-Arginine (L-NNA, 1 m9/kB, i.p.), an inhibitor of nitric oxide synthase. The FFE-induced decrease in MABP was significantly increased by pretreatment with L-NNA and was increased by pretreatment with PPN, Dut was inhibited by pretreatment with ODQ and IDN, This results were suggested that the mechanism of FF was mediated by nitric oxide synthase and adrenalic ${\beta}$ receptor.