• Title/Summary/Keyword: reduced frequency

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A Design of Prescaler with High-Speed and Low-Power D-Flip Flops (고속 저전력 D-플립플롭을 이용한 프리스케일러 설계)

  • Park Kyung-Soon;Seo Hae-Jun;Yoon Sang-Il;Cho Tae-Won
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.8 s.338
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    • pp.43-52
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    • 2005
  • An prescaler which uses PLL(Phase Locked Loop) must satisfy high speed operation and low power consumption. Thus the performance or TSPC(True Single Phase Clocked) D-flip flops which is applied at Prescaler is very important. Power consumption of conventional TSPC D-flip flops was increased with glitches from output and unnecessary discharge at internal node in precharge phase. We proposed a new D-flip flop which reduced two clock transistors for precharge and discharge Phase. With inserting a new PMOS transistor to the input stage, we could prevent from unnecessary discharge in precharge phase. Moreover, to remove the glitch problems at output, we inserted an PMOS transistor in output stage. The proposed flip flop showed stable operations as well as low power consumption. The maximum frequency of prescaler by applying the proposed D-flip flop was 2.92GHz and achieved power consumption of 10.61mw at 3.3V. In comparison with prescaler applying the conventional TSPC D-flip $flop^[6]$, we obtained the performance improvement of $45.4\%$ in the view of PDP(Power-Belay-Product).

An Experimental Study on the Effect of Low Fin Tube Geometry on Pool Boiling of a LiBr Solution (낮은 핀관의 형상이 LiBr 수용액의 풀 비등에 미치는 영향에 대한 실험적 연구)

  • Kim, Nae-Hyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.7
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    • pp.591-598
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    • 2015
  • Pool boiling heat transfer coefficients of a LiBr solution were obtained for seven low fin tubes having different fin pitch and fin height. The test range covered saturation pressure from 7.38kPa to 101.3kPa, heat flux from $20kW/m^2$ to $40 kW/m^2$ and LiBr concentration from 0% to 50%. The optimum fin geometry for the present experimental range turned out to be 26 fpi with 0.18 mm fin height.The advantage of added heat transfer area and the disadvantage of slower bubble growth and departure appear to have yielded an optimum fin pitch. The heat transfer coefficient decreased as saturation pressure decreased and Libr concentration increased. The reason may be attributed to the low saturation pressure, which increased the bubble departure diameter and decreased the bubble departure frequency. As the LiBr concenreation increased, the saturation temperature increased and the mass diffusion rate decreased, which resulted in a reduced heat transfer coefficient. The heat transfer coefficients of the low fin tube were greater than those of the smooth tube. Correlations were developed based on the present data.

Study on the Development of a Standard Instrument of Diagnosis and Assessment for Spleen Qi Deficiency Pattern (脾氣虛證(비기허증) 진단평가도구 개발 연구)

  • Oh, Hye-Won;Lee, Ji-Won;Kim, Je-Shin;Song, Eun-Young;Shin, Seung-Won;Han, Ga-Jin;Lu, Huanyu;Lee, Jun-Hee
    • The Journal of Korean Medicine
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    • v.35 no.1
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    • pp.157-170
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    • 2014
  • Objectives: The purpose of this study was to develop a standard instrument of diagnosis and assessment for spleen qi deficiency pattern. Methods: Reports published in Korea and China related to spleen qi deficiency pattern were selected. Assessments of selected references were performed to select major symptoms of spleen qi deficiency pattern. Korean translation and review by a Korean linguist were performed to create a draft of [Standard instrument of diagnosis and assessment for spleen qi deficiency (for subject)]. The final [Standard instrument of diagnosis and assessment for spleen qi deficiency (for subject)] was completed after assessment on inclusion or exclusion, on importance of items and on validity of translation by an expert committee, consisting of professors from the National College of Korean Medicine. Results & Conclusions: 1. 14 major symptoms were selected by frequency from 45 references which were related to standard identification of spleen qi deficiency pattern, translated into Korean and reviewed by a Korean linguist. 2. 11 symptoms were selected after assessment on inclusion yes or no by the expert group. Items were listed in order of importance: tiredness of extremities (肢体倦怠), sallow complexion (面色萎黃), reduced appetite (食欲减退), abdominal distension after eating (腹胀食後尤甚), inability to eat (納少), pale tongue and white fur (舌淡苔白), lethargy (神疲), emaciation (消瘦), loose stool (大便溏薄), shortness of breath and reluctance to speak (少氣懶言), and weak pulse (脈緩弱). 3. Final [Standard instrument of diagnosis and assessment for spleen qi deficiency (for subject)] was completed after assessment of translation validity, reflection of individual opinions by the expert committee, and application of weighted value computed from assessment on importance of items.

Efficacy of Lactobacillus Acidophilus in Treatment of Acute Diarrhea in Children (소아의 급성 설사에서 Lactobacillus Acidophilus의 치료 효과)

  • Han, Hye Jung;Han, Hye Jung;Lee, Hye Sun;Lee, In Sil;Yang, Hae Joung
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.7 no.1
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    • pp.24-30
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    • 2004
  • Purpose: Acute diarrhea in young children is a major problem in pediatric hospitals worldwide. We evaluated the clinical efficacy of orally administered Lactobacillus acidophilus in the treatment of acute diarrhea in children. Methods: From September 2002 to July 2003 at National Police Hospital 41 children aged 3 months to 5 years with acute diarrhea were enrolled in this study. The patients were randomized to one of two groups to receive either $0.5{\times}10^8$ colony forming unit (CFU) of L. acidophilus or matching placebo on admission and every 8 hours during hospitalization. Results: The mean duration of diarrhea in all 41 children was decreased (p=0.001) in the L. acidophilus (40.5 hours) group compared to the placebo (56.6 hours) group. Stool frequency was also reduced (p=0.01) on the 3rd day in the L. acidophilus group. Rotavirus was identified in 58% of the patients. The decrease of duration of diarrhea was more significant in rotavirus-negative patients (p=0.002) compared to the rotavirus-positive patients (p=0.027). Conclusion: L. acidophilus shows to be an effective therapeutic agent in acute diarrhea in children. Further studies are needed to confirm the present findings.

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The Role of Bmi1 in Pilocarpine-induced Status Epilepticus in Mice (Pilocarpine에 의해 유도된 생쥐 경련중첩증에서 Bmi1의 역할)

  • Pyeon, Hae-In;Bak, Jia;Choi, Yun-Sik
    • Journal of Life Science
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    • v.30 no.6
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    • pp.513-521
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    • 2020
  • B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi1) is a polycomb group protein and a core component of polycomb repressive complex 1. Initial research into Bmi1 has focused on its role in tumorigenesis, and it is generally accepted that it is important for the proliferation and survival of cancer cells. However, more recent studies have revealed that Bmi1 is downregulated in brains with neurodegenerative disease and that it regulates the function of mitochondria and reactive oxygen species levels. In this study, we tested the therapeutic potential of Bmi1 in pilocarpine-induced seizures in Bmi1-knockout mice. Bmi1 expression transiently increased in the hippocampal CA1 and CA3 and the dentate gyrus following pilocarpine-induced status epilepticus (SE). In terms of seizure behavior, SE induction was 43.14% and 53.57% for Bmi1+/+ and Bmi1+/- mice, respectively. However, there was no significant difference in mortality or hippocampal damage between the two groups. Two months after SE induction, the frequency of epileptic seizures in the Bmi1+/- mice was 50% lower than in the control group, although the difference was not statistically significant. In addition, mossy fiber outgrowth in the Bmi1+/- mice was significantly higher than in their wild-type littermates. Taken together, these data indicate that reduced Bmi1 activity increases pilocarpine-induced seizure probability and mossy fiber outgrowth.

The Effect of Ear Reflexotherapy on Back Pain of Working Women in Middle Age (귀 자극요법 적용이 중년 여성 근로자의 요통에 미치는 효과)

  • Park, Kyung-Sook;Ha, Eun-Ho;Kim, Yu-Na;Kwon, Soo-Jin;Ru, Lee-Jung;Song, Ju-Hyun;Woo, Yong-Wha;Lee, Jae-Yeon;Chun, In-Hee;Kang, Hyun-Kyung;Park, Hee-Jung;Lee, Eun-Joo;Lee, Jae-On
    • Journal of muscle and joint health
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    • v.17 no.1
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    • pp.14-24
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    • 2010
  • Purpose: The purpose of this study was to investigate the effect of ear reflexotherapy on back pain of working women in middle age. Methods: The quasi-experimental, nonequivalent control group pretest-posttest design was used for the study. Total of 56 participants composed of experimental group (n=26) and control group (n=30), who were working in four hospitals in urban area. The degree of back pain after ear reflexotherapy was measured by VAS. The data were analyzed by frequency, percent, t-test and $X^2$-test. Results: The degree of back pain after ear reflexotherapy in the experimental group was significantly reduced, while there was no difference in control group. There was a significant difference between the experimental group and control group in the degree of back pain after ear reflexotherapy (t=3.702, p=.001). Conclusion: Application of ear reflexotherapy was effective for employed women in middle age and it needs to be further evaluated among the other population.

Improvement of Fat Suppression and Artifact Reduction Using IDEAL Technique in Head and Neck MRI at 3T

  • Hong, Jin Ho;Lee, Ha Young;Kang, Young Hye;Lim, Myung Kwan;Kim, Yeo Ju;Cho, Soon Gu;Kim, Mi Young
    • Investigative Magnetic Resonance Imaging
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    • v.20 no.1
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    • pp.44-52
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    • 2016
  • Purpose: To quantitatively and qualitatively compare fat-suppressed MRI quality using iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) with that using frequency selective fat-suppression (FSFS) T2- and postcontrast T1-weighted fast spin-echo images of the head and neck at 3T. Materials and Methods: The study was approved by our Institutional Review Board. Prospective MR image analysis was performed in 36 individuals at a single-center. Axial fat suppressed T2- and postcontrast T1-weighted images with IDEAL and FSFS were compared. Visual assessment was performed by two independent readers with respect to; 1) metallic artifacts around oral cavity, 2) susceptibility artifacts around upper airway, paranasal sinus, and head-neck junction, 3) homogeneity of fat suppression, 4) image sharpness, 5) tissue contrast of pathologies and lymph nodes. The signal-to-noise ratios (SNR) for each image sequence were assessed. Results: Both IDEAL fat suppressed T2- and T1-weighted images significantly reduced artifacts around airway, paranasal sinus, and head-neck junction, and significantly improved homogeneous fat suppression in compared to those using FSFS (P < 0.05 for all). IDEAL significantly decreased artifacts around oral cavity on T2-weighted images (P < 0.05, respectively) and improved sharpness, lesion-to-tissue, and lymph node-to-tissue contrast on T1-weighted images (P < 0.05 for all). The mean SNRs were significantly improved on both T1- and T2-weighted IDEAL images (P < 0.05 for all). Conclusion: IDEAL technique improves image quality in the head and neck by reducing artifacts with homogeneous fat suppression, while maintaining a high SNR.

Ecological Changes of the Larix kaempferi Plantations and the Restoration Effects Confirmed from the Results (일본잎갈나무조림지의 생태적 변화와 그 결과를 통해 확인된 복원 효과)

  • Kim, Se-Mi;An, Ji-Hong;Lim, Yun-Kyung;Pee, Jung-Hun;Kim, Gyung-Soon;Lee, Ho-Young;Cho, Yong-Chan;Bae, Kwan-Ho;Lee, Chang-Seok
    • Korean Journal of Ecology and Environment
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    • v.46 no.2
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    • pp.241-250
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    • 2013
  • Developmental process of vegetation over years after afforestation was analyzed in the Japanese larch (Larix kaempferi) plantations with different stand ages. The height and diameter of Japanese larch increased rapidly until 24 years after afforestation and tended to be blunted thereafter. The density of Japanese larch was similar with each other in the 8 and 17 years old stands but was reduced greatly in the 24 years old plantation and changing little thereafter. The floristic composition of the Japanese larch plantation did not show any clear trend depending on stand ages. The differences of species composition among plantation themselves with different ages were bigger than those between plantations and the reference stands, Mongolian oak (Quercus mongolica) stands. Japanese larch plantations showed a trend of succession to native vegetation dominated by Mongolian oak based on the results of analysis of frequency distribution by diameter class of major tree species. Species richness and diversity of all plantations were higher than those of the reference vegetation. As were shown in the above mentioned results, it can be evaluated that Japanese larch plantations practiced in the level of the functional restoration achieved successful restoration based on the floristic composition similar to the reference vegetation, the successional trend toward native vegetation, and higher species diversity compared with the reference vegetation.

Impact of IL-2 and IL-2R SNPs on Proliferation and Tumor-killing Activity of Lymphokine-Activated Killer Cells from Healthy Chinese Blood Donors

  • Li, Yan;Meng, Fan-Dong;Tian, Xin;Sui, Cheng-Guang;Liu, Yun-Peng;Jiang, You-Hong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7965-7970
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    • 2014
  • One of the goals of tumor immunotherapy is to generate immune cells with potent anti-tumor activity through in vitro techniques using peripheral blood collected from patients. However, cancer patients generally have poor immunological function. Thus using patient T cells, which have reduced in vitro proliferative capabilities and less tumor cell killing activity to generate lymphokine-activated killer (LAK) cells, fails to achieve optimal clinical efficacy. Interleukin-2 (IL-2) is a potent activating cytokine for both T cells and natural killer cells. Thus, this study aimed to identify optimal donors for allogeneic LAK cell immunotherapy based on single nucleotide polymorphisms (SNP) in the IL-2 and IL-2R genes. IL-2 and IL-2R SNPs were analyzed using HRM-PCR. LAK cells were derived from peripheral blood mononuclear cells by culturing with IL-2. The frequency and tumor-killing activity of LAK cells in each group were analyzed by flow cytometry and tumor cell killing assays, respectively. Regarding polymorphisms at IL-2-330 (rs2069762) T/G, LAK cells from GG donors had significantly greater proliferation, tumor-killing activity, and IFN-${\gamma}$ production than LAK cells from TT donors (P<0.05). Regarding polymorphisms at IL-2R rs2104286 A/G, LAK cell proliferation and tumor cell killing were significantly greater in LAK cells from AA donors than GG donors (P<0.05). These data suggest that either IL-2-330(rs2069762)T/G GG donors or IL-2R rs2104286 A/G AA donors are excellent candidates for allogeneic LAK cell immunotherapy.

The Design of Feature Selecting Algorithm for Sleep Stage Analysis (수면단계 분석을 위한 특징 선택 알고리즘 설계)

  • Lee, JeeEun;Yoo, Sun K.
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.10
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    • pp.207-216
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    • 2013
  • The aim of this study is to design a classifier for sleep stage analysis and select important feature set which shows sleep stage well based on physiological signals during sleep. Sleep has a significant effect on the quality of human life. When people undergo lack of sleep or sleep-related disease, they are likely to reduced concentration and cognitive impairment affects, etc. Therefore, there are a lot of research to analyze sleep stage. In this study, after acquisition physiological signals during sleep, we do pre-processing such as filtering for extracting features. The features are used input for the new combination algorithm using genetic algorithm(GA) and neural networks(NN). The algorithm selects features which have high weights to classify sleep stage. As the result of this study, accuracy of the algorithm is up to 90.26% with electroencephalography(EEG) signal and electrocardiography(ECG) signal, and selecting features are alpha and delta frequency band power of EEG signal and standard deviation of all normal RR intervals(SDNN) of ECG signal. We checked the selected features are well shown that they have important information to classify sleep stage as doing repeating the algorithm. This research could use for not only diagnose disease related to sleep but also make a guideline of sleep stage analysis.