• Title/Summary/Keyword: Am

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Pre-distorter Method Using LUT with 2ι Partition Interpolation in the OFDM System (OFDM 시스템에서 2ι 분할 보간을 LUT에 결합한 전치왜곡기에 관한 연구)

  • 권오주;이호근;하영호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.7A
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    • pp.668-675
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    • 2002
  • This paper proposes pre-distorter combined LUT with 2ιpartition interpolation method to reduce nonlinear distortion which was caused by high PAPR and to update LUT quickly. Pre-distorted gain and phase can be found by using LUT which consisted of AM/AM and AM/PM value, and OFDM signal amplitude. The proposed 2ιpartition interpolation can accurately find predistorted gain and phase using bit shift and add component instead of increasing size of LUT which requires increasing the amount of computation. The performance of the proposed method was measured by the difference between HPA input and output characteristics by the LUT size, constellation, SER performance by the HPA, and LUT update error by the HPA characteristic changes. As a result, it is shown that when the size of the LUT is 32 and 64 for 16-QAM and 64-QAM, nonlinear distortion nearly didn't occurred.

Implementation of the Vehicle Antenna for the AM/FM/TDMB/GPS Receiver (AM/FM/TDMB/GPS 수신용 전장 안테나 제작)

  • Kim, Joo-Man;Son, Tae-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.5
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    • pp.105-113
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    • 2009
  • In this paper, a vehicle antenna for AM, FM, TDMB, GPS systems was designed and implemented. AM antenna loaded into small space of shark shape was designed by ferrite turn style antenna. For the FM and TDMB antenna, folded monopole antenna which helical is folded was applied. GPS antenna for achieving characteristics both bandwidth and gain improvement was designed microstrip patch that has air substrate and fractal structure. Receiving signal strengths by the measurement were presented for the AM, FM and TDMB antenna. AM signal strength was -65.7dBm, this strength is almost as same conventional pole antenna as -63.4dBm. It can be replaced conventional pole or glass antenna by the studied antenna. Signal strengths for FM and TDMB were -55.66 and -43.50dBm at center frequency, they are 5~10dB higher than conventional antenna. Measurements of bandwidth and gain for the GPS antenna showed 135 MHz under VSWR 2 : 1 and 4.31dBi, gains over GPS band were 3~5dB higher than ceramic patch antenna.

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Effects of Platelet-Activating Factor on Tumor Necrosis $Factor-_{\alpha}$ Production by Muramyl Dipeptide- or Silica-Stimulated Alveolar Macrophages

  • Lee, Ji-Hee;Hah, Jong-Sik
    • The Korean Journal of Physiology
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    • v.30 no.1
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    • pp.77-83
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    • 1996
  • Platelet-activating factor(PAF) is a phospholipid mediator of pulmonary inflammation, and immunologic reaction. In this study, the role of PAF on tumor necrosis factor$(TNF_{-{\alpha}})$ production by rat alveolar macrophages(AM) was examined. When PAF $(10^{-12}{\sim}10{-16}\;M)$ alone was added to AM culture, $(TNF_{-{\alpha}})$ production was not significantly increased above the resting level. In contrast, the combined addition of PAF $(10^{-6}\;M)$ and muramyl dipeptide(MDP) $(1.0\;{\mu}g\ml)$ to AM cultures markedly enhanced $(TNF_{-{\alpha}})$ production with 8.2 fold increase compared with AM culture in resting state. This potentiative effect was 313% above the sum of the separate effects of PAF and MDP. To characterize MDP effects on $(TNF_{-{\alpha}})$ production, the dose-response of AM cultured with various concentrations of MDP was tested. High level of MDP $(10\;{\mu}g\ml)$ could not significantly enhance the potentiation effect on $(TNF_{-{\alpha}})$ production compared with AM cultures with low level of MDP $(0.1\;{\mu}g\ml)$, i.e. 112.5% vs 107.8%, respectively when $10^{-10}$ M of PAF was simultaneously added to the cell culture. These data support that the potentiation of TNF. g production in AM culture is mediated by PAF rather than MDf It was also evaluated whether the similar result was obtained in silica, respirable toxic particle-treated AM culture. $(TNF_{-{\alpha}})$ production was also significantly enhanced in the PAF $(10^{-6}\;M)$ and silica $(50\;{\mu}g\ml)$-added cell cultures with 4.7 fold above the value of silica alone-stimulated cells. These results indicate that PAF can potentiate $(TNF_{-{\alpha}})$ production by MDP-or silica- stimulated AM and suggest that PAF may play a potent role in lung inflammation and disease associated with microbe and occupational dust exposures.

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Sequential separation of 90Sr, 241Am, 239,240Pu and 238Pu by radioanalytical techniques (방사능 분석기술을 이용한 90Sr, 239,240Pu, 238Pu, 241Am 축차분리)

  • Lee, Myung Ho;Park, Kyoung Kyun;Kim, Jong-Yun;Park, Yeong Jae;Kim, Won Ho
    • Analytical Science and Technology
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    • v.18 no.6
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    • pp.469-474
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    • 2005
  • This paper presents a quantitative method of sequential separation of $^{90}Sr$, $^{241}Am$ and Pu radionuclides with an anion exchange resin and a Sr-Spec resin. The Pu isotopes were purified with an anion exchange resin. The americium and strontium fractions were separated from the matrix elements with an oxalate co-precipitation method. Americium fraction was separated from the strontium fraction with iron co-precipitation method and purified from lanthanides with anion exchange resin. Strontium-90 was purified from other hindrance elements with the Sr-Spec resin after oxalate co-precipitation. The measurement of Pu and Am isotopes was carried out by an ${\alpha}$-spectrometer. Strontium-90 was measured by a liquid scintillation counter. The radiochemical procedure of $^{90}Sr$, $^{241}Am$ and Pu radionuclides investigated in this study has been validated by application to IAEA-Reference soils.

A Literature Review of Clinical Studies Using Sa-am Acupuncture

  • Lim, Jinwoong;Kim, Yong-hwa;Kim, Yu-gon;Jeong, Hyeon-gyo;Shin, Kyung-moon;Shin, Dong-hoon;Jeong, Hwe-joon;Kang, Deok;Yang, Jae-woo;Oh, Ji-hoon;Yoon, Hong-ryoul;Jo, Jae-sung
    • Journal of Acupuncture Research
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    • v.38 no.3
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    • pp.183-191
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    • 2021
  • Sa-am acupuncture originated in the Chosun Dynasty and is a distinct feature of Korean medicine. It has been used to treat various diseases and conditions in clinical practice however, there is insufficient scientific evidence to support the use of Sa-am acupuncture. We aimed to comprehensively review the clinical studies of Sa-am acupuncture retrieved from national and international databases (MEDLINE, EMBASE, the China National Knowledge Infrastructure, and 3 Korean databases). There were 52 articles reviewed including 29 case studies, 19 randomized controlled trials (RCTs), and 4 uncontrolled trials. Neurological disorders were the most frequently studied, and kidney tonification, and directional supplementation and draining were the most frequently used methods. Overall, the outcomes were generally positive however, there were many additional treatments together with Sa-am acupuncture reported in the case reports, and the quality of evidence was low in the RCTs. Future studies should report the detailed method of practicing Sa-am acupuncture treatment and focus on the specific effect of Sa-am acupuncture with rigorous design to scientifically support the clinical use of Sa-am acupuncture.

A study on pearl millet (Pennisetum glaucum L.) plant Biochemical and histochemical changes inoculated with indigenous AM fungi under Barren soil

  • Pal, Ajay;Pandey, Sonali
    • Journal of Plant Biotechnology
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    • v.44 no.2
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    • pp.203-206
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    • 2017
  • The soil organisms that develop beneficial Symbiotic relationships with plants roots and contribute to plant growth are mycorrhizal (AM) fungi. Arbuscular mycorrhizal inoculations change the growth and biochemical composition of the host plant and soil. Mycorrhizal root systems do augment the absorbing area of roots from 10 to 100 times thereby greatly improving the ability of the plants to utilize the soil resources. A pot experiment was conducted during the kharif seasons at Jaipur, Rajasthan, to find out the effects of three different indigenous AM fungi i.e. Glomus mosseae, Glomus fasciculatum and Gigaspora decipiens either single and in combination inoculation on biochemical and histochemical changes of Pearl millet (Pennisetum glaucum L.) grown under barren soil conditions. The AM fungus has shown to improve the tolerance of plant to drought stress. Experimental results showed that AM fungi treated plants improved their plants growths, biochemical and histochemical changes as compared to non-mycorrhizal treatments. The AM fungi inoculated plant was found to be attaining maximum plant biochemical and histochemical substances in Glomus mosseae (alone) and also Glomus mosseae + Glomus fasciculatum treatments.

The Depressive effect of Sa-Am Acupuncture(膀胱正格) treatment in Stroke Patients (뇌졸중 환자에서 사암침의 혈압강하에 대한 고찰)

  • Park, Young-soo;Kim, Eun-mi;Kim, Young-il;Hong, Kwon-eui;Lee, Hyun
    • Journal of Acupuncture Research
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    • v.21 no.4
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    • pp.217-223
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    • 2004
  • Objective: The aim of this research was to investigate the depressive effect of Sa-am Acupuncture(膀胱正格) in stroke patients. Methods: We measured the blood pressure of the patients who were admitted in the Oriental Medical hospital of Dae-Jeon University from June. 2003. to September. 2003. If systolic blood pressure was over 160mmHg or diastolic blood pressure was over 100 mmHg, 40 patients were treated by Sa-am Acupuncture(膀胱正格) and the other 20 patients were taken a rest in bed. Then 30 minutes and 60 minutes later, systolic, diastolic blood pressure were measured. Results: After 30 minute treatment, Sa-am Acupuncture(膀胱正格) significantly depressed the systolic and diastolic blood pressure, but bedrest can't do it. After 60 minute treatment, both Sa-am Acupuncture(膀胱正格) and bedrest significantly depressed the systolic and diastolic bood pressure. Conclusion: These results suggest that Sa-am Acupuncture(膀胱正格) is effective in depressing the systolic and diastolic blood pressure.

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Species Diversity of Arbuscular Mycorrhizal Fungi Community Depending on Environmental Conditions of Forest Soils (산림(山林)의 토양환경(土壤環境) 조건(條件)에 따른 수지상(樹枝狀) 균근(菌根)(AM)균(菌) 집단(集團)의 종(種) 다양성(多樣性))

  • Koo, Chang-Duck
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.1
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    • pp.70-79
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    • 2000
  • Arbuscular mycorrhizal(AM) fungi have significant role for ecosystem structure and function. They are the major component of forest soil ecosystems and critically important for water and nutrient cycling in the system. To understand the ecology of AM fungi the fungal spores were collected, identified and counted in forest soils under various climatic and edaphic conditions. In relation to soil depth 90% of AM fungi spores and mycorrhizas distributed within 15cm soil depth. Number of spores per $100m{\ell}$ forest soil volume was 5 to 36 spores from 1 to 3 fungal species. AM fungal species diversity was higher in warmer climates, and more moist and fertile soils. The most frequently found species were Gigaspora decipiens irrespective of soil moisture and Gi. gigantea irrespective of soil fertility. In the Jeju island the soils of Cryptomeria japonica plantations and Miscanthus sinensis var. purpurascens meadow had more AM spores than the other soils. We suggest AM fungi be considered as keystones species when restoring a disturbed forest ecosystem.

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A Study on the Formula Structure of Sa-am Acupuncture and the Theory of Sovereign, Minister, Assistant and Courier (사암침법(舍巖鍼法)의 처방구조(處方構造)와 군신좌사(君臣佐使)의 관계에 대한 소고(小考))

  • Lee, In-Seon;Cho, Sung-Woo;Kwon, Jung-Nam
    • Journal of Acupuncture Research
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    • v.27 no.6
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    • pp.23-30
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    • 2010
  • Objectives : This study was undertaken in order to establish the composite principles of fomulas through the of Sa-am acupuncture therapy and the theory of sovereign, minister, assistant and courier. Methods : We analyzed the formula construction of Sa-am acupuncture therapy, and applied the theory of sovereign, minister, assistant and courier that was referred to in the preface of "Essential Rhymes on Acupuncture and Moxibustion by Master Sa-am" to the analysis of formula construction. Results & Conclusions : 1. Sa-am acupuncture therapy was acupuncture and moxibustion method that inherited and developed progress contents of Chinese traditional acupuncture and moxibustion. 2. The theory of sovereign, minister, assistant and courier was based on the idea that acupuncture and herbal medicine had the same origins. 3. Formula constructions of Sa-am acupuncture therapy were formed complicatedly, but reflected the theory of sovereign, minister, assistant and courier. 4. The supplementing acupuncture point that is Chunbu-point in other merdian became Sovereign, the draining acupuncture point that is Chunbu-point in other merdian became Minister, and the supplementing and draining acupuncture points in same merdian became Assistant and Courier that mean leading merdian points.

Sa-Am Acupuncture with Spleen Seung-gyuck induces an acute increase of radial pulse parameters related to arterial stiffness in healthy subjects: A comparative study of Jung-gyuck and Seung-gyuck

  • Yim, Yun-Kyoung
    • The Journal of Korean Medicine
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    • v.35 no.2
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    • pp.19-27
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    • 2014
  • Objectives: To investigate the different effects of Sa-Am acupuncture with Spleen Jung-gyuck and Spleen Seung-gyuck on the radial pulse in healthy subjects. Methods: Sixty healthy volunteers (30 males and 30 females) participated in this study. The participants were randomly divided into three groups: control (C), Sa-Am acupuncture with Spleen Jung-gyuck (SP+) and Sa-Am acupuncture with Spleen Seung-gyuck (SP-). The radial pulse was measured using a multi-step tonometry system before, and 0, 30 and 60 minutes after acupuncture. Results: The heart rate adjusted radial augmentation index (RAI/HR) and high-tensioned pulse area (W area) significantly increased in the SP- group compared to the C and SP+ groups in males. The systolic pulse period (T4) increased significantly in the SP- group compared to the C and SP+ groups in females. The RAI/HR had positive correlations with W area and T4. Conclusion: The effects of Sa-Am acupuncture with Spleen Jung-gyuck and Spleen Seung-gyuck are different. Sa-Am acupuncture with Spleen Seung-gyuck induces acute increases of radial pulse parameters related to arterial stiffness in healthy subjects.