• Title/Summary/Keyword: Phase-control

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A Nulling Anti-Jamming Scheme for the Polyphase Filter Bank-Based Satellite Repeat System (다상 필터 뱅크 기반의 위성 중계시스템을 위한 항재밍 기법의 연구)

  • Oh, Jin-O;Im, Sung-Bin;Ko, Hyun-Suk
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.7
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    • pp.39-47
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    • 2012
  • The combination of the broadband property and the wide area coverage of satellite communications enables high speed transmission. Every user in the region under the satellite beam coverage can tranceiver and one can simultaneously communicate with multiple users. For these reasons, it is one of commendable telecommunication networks for information transfer. Since the satellite communications use open channels, it is likely to cause jamming with unwanted interference signals. In the thesis, APSK (Amplitude Phase Shift Keying) is employed, which is recommended for DVB-S2 due to high-speed transmission and excellent bandwidth efficiency. For obtaining reliable communication under the jamming environments, the communication satellite transponder rests on the polyphase filter bank structure, which enables switching among the subchannels and gain control on each subchannel, resulting in effectively eliminating jamming. Furthermore, the nulling scheme, one of the various anti-jamming approaches, is investigated, in which unwanted jamming signals are eliminated in the frequency domain after passing through the analysis part of the polyphase filter bank. The performance of the nulling scheme is evaluated for tone jamming and partial band jamming in terms of BER and EVM. The simulation results indicate that the nulling scheme improve the BER and EVM performance over the case without any anti-jamming approach.

Effect of the Head Support on a Change in Muscle Thickness for Longus Colli and Sternocleidomastoid During Cranio-Cervical Flexion Test in Subjects With Forward Head Posture (앞쪽머리자세를 가진 대상자의 머리-목 굽힘 검사 시 머리받침 유무에 따른 긴목근과 목빗근의 근두께 변화량 비교)

  • Park, Jun-sang;Song, Si-jeong;Jung, Hee-seok;Kwon, Oh-yun
    • Physical Therapy Korea
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    • v.23 no.3
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    • pp.11-20
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    • 2016
  • Background: A forward head posture (FHP) is one of the most common types of poor head posture in patients with neck disorder. A prolonged FHP might increase pressure on the posterior cranio-cervical structure and exhibit reduced performance on a cranio-cervical flexion test (CCFT). CCFT is included to activate deep cervical flexor muscles and inhibit excessive activation of superficial cervical flexor muscles. Therefore, the selective activation of deep cervical flexors is needed for effective exercise for FHP. Objects: The purpose of this study was to compare muscle thickness between longus colli (Lco) and sternocleidomastoid (SCM) using ultrasonography in subjects with FHP depending on head support. Methods: This was a cross-sectional, case-control research design study. The ultrasonographic images of Lco and SCM were taken in 17 subjects with FHP during the 5 phases of the CCFT with and without a head support. Towel was used for supporting head to make the neutral head position in supine. Changes in muscle thickness during the test were calculated to infer muscle activation. Data were analyzed using repeated measures of two-way analysis of variance with the significance level of .05. Results: When subjects performed the CCFT with head support, there was a significant difference in muscle thickness of Lco and SCM (p<.05). According to a post hoc paired t-test, change of thickness of Lco was greater at all phases, and change of thickness of SCM muscle was less at phase 4 and 5 in condition with head support (p<.01) compared to condition without head support (p<.01). Conclusion: The result of this study suggest that applying head support for neutral head position during CCFT could be a useful method for activating Lco muscle without excessive activation of SCM muscle.

The Effects of Dynamic Functional Electrical Stimulation With Treadmill Gait Training on Functional Ability, Balance Confidence and Gait in Chronic Stroke Patients

  • Cho, Young-Ki;Ahn, Jun-Su;Park, Yong-Wan;Do, Jung-Wha;Lee, Nam-Hyun;Kwon, Oh-Yun
    • Physical Therapy Korea
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    • v.21 no.4
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    • pp.23-33
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    • 2014
  • The aim of this study was to evaluate the effects of walking on a treadmill while using dynamic functional electrical stimulation (Dynamic FES) on functional ability and gait in chronic stroke patients. This was a prospective, randomized controlled study. Twelve patients with chronic stroke (>24 months) who were under grade 3 in dorsiflexor strength with manual muscle test were included and randomized into intervention (Dynamic FES) ($n_1$=7) and control (FES) ($n_2$=5). Both the Dynamic FES group and FES group were given a neuromuscular development treatment. The Dynamic FES group has implemented a total of 60 minutes of exercise treatment and gait training with Dynamic FES application. The FES group, with the addition of applying FES while sitting, has also implemented a total of 90 minutes of gait training on treadmill after the exercise treatment. Both two groups accomplished the program, twice a week, for a total of 24 times in a 12-week period. Exercise treatment, gait training on treadmill, and both Dynamic FES and FES were implemented for 30 minutes each. Korean version activities-specific balance confidence scale (K-ABC) was measured to determine self-efficacy in balance function. Timed up and go (TUG) test was performed to evaluate the physical performance. K-ABC, TUG, Berg balance scale (BBS), modified physical performance test (mPPT) and G-walk were evaluated at baseline and at 12 weeks. After 12 weeks, statistically significant differences (p<.05) were apparent in the Dynamic FES group in the changes in K-ABC and BBS. mPPT, TUG, gait speed, stride length and stance phase duration (%) were compared with the FES group. K-ABC had higher correlation to BBS, along with mPPT to TUG. Our results suggest that walking with Dynamic FES in chronic stroke patients may be beneficial for improving their balance confidence, functional ability and gait.

Anticancer Effects of Cultivated Orostachys japonicus on Human Prostate Cancer Cells (인체 전립선 암세포에서 재배 와송의 항암효과)

  • Won, Yeong Seon;Lee, Ju Hye;Kwon, Soon Jae;Ahn, Dong Uk;Shin, Dong Young;Seo, Kwon Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.1
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    • pp.67-73
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    • 2014
  • This study was performed to determine the anticancer effects of cultivated Orostachys japonicus (COJ) and wild Orostachys japonicus (WOJ) on primary human prostate cancer cells (RC-58T/h/SA#4 cells). The morphology of cells treated with COJ and WOJ was distorted to shrunken cell masses. In addition, cell death induced by COJ and WOJ was associated with increased population of cells in sub-G1 phase as well as the formation of apoptotic bodies and nuclear condensation. COD and WOJ markedly reduced the number of viable prostate cancer cells in a dose-dependent manner, and cell numbers were lower than control cells. COJ and WOJ also inhibited increases in cell proliferation induced by environmental hormones such as dioxin and bisphenol A in charcoal-treated FBS (cFBS) medium. COJ and WOJ methanol extracts at the tested concentrations (150, 300, and 600 ${\mu}g/mL$) also dose-dependently inhibited cell proliferation induced by environmental hormones. These results indicate that COJ and WOJ exert anticancer effects on primary human prostate cancer cells.

Refinement of the manganese nitrate solution prepared by leaching the reduced Ferromanganeses dust with nitric acid. (용해도 차이를 이용한 질산망간 용액의 정제)

  • Cho Young-Keun;Song Young-Jun;Lee Gye-Seung;Shin Kang-Ho;Kim Hyung-Seok;Kim Yun-Che;Cho Dong-Sung
    • Resources Recycling
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    • v.12 no.1
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    • pp.33-40
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    • 2003
  • Mn was extracted by using a nitric acid from the reduced ferromanganese dust and the basic experiments were taken to refine the manganese nitrate solution by means of precipitation of Ca, Mg oxalate. The dust was generated in AOD process producing a medium-low carbon ferromanganese and collected in the bag filter. Manganese oxide content in the dust was about 90% and its phase was confirmed as $Mn_3$$O_4$. $Mn_3$$O_4$ in the dust was reduced to MnO by roasting with activated charcoal. The main impurities in the extracted solution prepared by leaching the reduced dust with nitric acid were Na, K, Fe, Si, Ca, Mg etc. Among them, Fe was removed by controlling pH of the solution more than 4 and precipitating $Fe(OH)_3$, simultaneously silicious material solved in the solution was removed by co-precipitation with the ferric hydroxide. Addition of 150 g reduced dust into 4N HNO3 solution 1$\ell$ was appropriate to control the pH of the solution to pH 4. To differ greatly the solubilities of manganese oxalate and calcium or magnesium oxalate in a solution containing a high concentration of Mn, pH of 4 or less and addition of ($NH_4$)$_2$$C_2$$O_4$ in equivalent with Ca and Mg are recommended. At this time, the higher temperature was the shorter the precipitation reaction time was needed.

A Pilot Study of Brief Eye Movement Desensitization and Reprocessing(EMDR) for Treatment of Acute Phase Schizophrenia (급성기 정신분열병의 치료로서 단기적인 안구운동 민감소실 및 재처리요법에 대한 예비연구)

  • Kim, Daeho;Choi, Joonho;Kim, Seok Hyeon;Oh, Dong Hoon;Park, Seon-Cheol;Lee, Sun Hye
    • Korean Journal of Biological Psychiatry
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    • v.17 no.2
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    • pp.94-102
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    • 2010
  • Objectives : Eye movement desensitization and reprocessing(EMDR) is a novel, time-limited psychotherapy originally developed for treatment of psychological trauma. The effectiveness of this therapy has been validated only for posttraumatic stress disorder ; however, EMDR is often applied to other psychiatric illnesses, including other anxiety disorders and depression. This pilot study tested the efficacy of EMDR added to the routine treatment for individuals with acute stage schizophrenia. Methods : This study was conducted in the acute psychiatric care unit of a university-affiliated training hospital. Inpatients diagnosed with schizophrenia were randomly assigned to either three sessions of EMDR, three sessions of progressive muscle relaxation(PMR) therapy, or only treatment as usual(TAU). All the participants received concurrent typical treatments(TAU), including psychotropic medication, individual supportive psychotherapy and group activities in the psychiatric ward. The Positive and Negative Syndrome Scale(PANSS), the Hamilton Depression Rating Scale and the Hamilton Anxiety Rating Scale were administered by a clinical psychologist who was blinded to the patients' group assignment. Results : Forty-five patients enrolled and forty patients(89%) completed the post-treatment evaluation. There were no between-group differences in the withdrawal rates of patients during the treatment or at the three-month follow-up session. All three groups improved significantly across each of the symptomatic domains including schizophrenia, anxiety, and depressive symptoms. However, a repeated measures ANOVA revealed no significant differences among the groups over time. Effect size for change in total PANSS scores was also similar across treatment conditions, but effect size for negative symptoms was large for EMDR(0.60 for EMDR, 0.39 for PMR and 0.21 for TAU only). Conclusion : These findings supported the use of EMDR in treating the acute stage of schizophrenia but the results failed to confirm the effectiveness of the treatment over the two control conditions in three sessions. Further studies with longer courses of treatment, more focused target dimensions of treatment, and a sample of outpatients are necessary.

Molecular Biological Study of Anti-cancer Effects of Bee Venom on Human Melanoma Cell (약침용봉독액(藥鍼用蜂毒液)이 흑색종세포(黑色腫細胞)에 미치는 항암효과(抗癌效果)에 대(對)한 분자생물학적(分子生物學的) 연구(硏究))

  • Park, Chan-Yol;Nam, Sang-Soo;Kim, Chang-Hwan;Lee, Jae-Dong;Kang, Sung-Keel;Lee, Yun-Ho;Ahn, Byoung-Choul
    • Journal of Acupuncture Research
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    • v.17 no.2
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    • pp.169-186
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    • 2000
  • To study anti-cancer effect and molecular biological mechanism of bee venom for aqua-acupuncture, the effects of bee venom on cell viability, apoptosis, and cell cycle were analyzed using MTT assay, tryphan blue assay, [3H]thymidine release assay, flow cytometric analysis, activity of caspase-3 protease activity assay, and immunocytometric analysis of PCNA. To explore whether anti-cancer effects of bee venom are associated with the transcriptional control of gene expression, quantitative RT-PCR analysis of apoptosis- and cell cycle-related genes was performed. The obtained results are summarized as follows: 1. The MTT assay demonstrated that cell viability was decreased by bee venom in a dose-dependant manner. 2. Significant induction of apoptosis was identified using tryphan blue assay, [$^3H$]thymidine release assay, and flow cytometric analysis of sub $G_1$ fraction. 3. In analysis of caspase-3 protease activity, the activity had increased significantly, in a dose-dependant manner. 4. Quantitative RT-PCR analysis of the apoptosis-related genes showed that Bcl-2 and $Bcl-X_L$ were down-regulated whereas Bax was up-regulated by bee venom treatment. 5. In flow cytometric analysis of cell cycle and immunocytometric analysis of PCNA expression, cell numbers of $G_1$ phase was increased by a dose-dependant manner. 6. In quantitative RT-PCR analysis of the cell cycle-related genes, p21, p27, and p57 were increased, while Cyclin D1, CDK4, c-Myc, c-Fos, and Histone H3 were decreased. In contrast, there were no remarkable changes in expression levels of CDC2 and c-Jun.

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A Study of Dance Movement Training on the Wellness of young Women (율동적 동작 훈련이 젊은 여성의 Wellness에 미치는 영향)

  • ;Lou Heber
    • Journal of Korean Academy of Nursing
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    • v.25 no.3
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    • pp.538-548
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    • 1995
  • Exercises are achievement oriented, the process is frequently perceived as hard and difficult Participants drop out from exercise programs in the middle of the training period. Dance movement, which is the deliberate and systematic use of movement, is enjoyable during the movement and provides opportunities for persons to express them-selves. Regular long term dance movement may in-duce a training effect with a decreased drop out rate. Dance movement could be one way to attain wellness, however, there have been few studies to evaluate both physiological and psychological aspects of dance movement. This study focused on evaluating the effects of dance movement training on body weight, resting blood pressure and heart rate, limb circumference and strength, stress response and subjective feelings. This quasi-experimental study was designed as a nonequivalent control group pre test -post test study. Ten healthy fe-male subjects, aged between 19 and 31 years volunteered for an eight week dance movement program. Ten healthy female subjects, between 19 and 21 years of age paticipated as controls. None of the subjects had performed regular physical activity for six months prior to the study. Dance movement was created with reference to Heber's movement guide. The Dance movement program consisted of approximately 30 minutes of dance, three days per week, for eight weeks. During each 30 minute work out, there were approximately 5 minutes of warm-up dancing, 20 minutes of conditioning dance and 5 minutes of cool-down dancing. The intensity for the conditioning phase was at between 60% and 65% of age-adjusted maximum heart rates. Body weight, resting blood pressure and heart rate, circumference of mid upper arm, mid thigh and mid calf, muscle strength of upper and lower limb, physical and psychological response to stress were measured prior to, and following the experimental treatment. Body weight was measured by digital weight scale(Kyung In Corp., Korea). Resting systolic and diastolic blood pressure were measured by sphygmomanometer, Resting heart rate was measured for one minute in a relaxed sitting position using the radial artery. Circumference of mid upper arm, mid thigh and mid calf was determined by tape measure. Muscle strength of the upper extremities was measured by a grip dynamometer (Takei Corp. No.1857, Japan) and that of the extremities was measured by the length of time the leg could be held at 45° Physical and psychological responses to stress were measured using the Symptoms of Stress (SOS)Scale. Paticipants in the dance movement were interviewed by the facilitator following the eight weeks, and their thematic responses about the dance movement were recorded. Following the eight week dance movement train-ing, body weight decreased significantly, circumference of mid thigh and mid calf increased. The length of time leg - raising could be held tended to increase following the dance movement training. Resting systolic and resting heart rate showed a tendency to decrease. Total mean score of stress response tended to de-crease, and mean score of habitual patterns, do-pression, anxiety / fear, anger and cognitive disorganization decreased remarkably following the eight week dance movement. Thematic responses about the dance movement were positive following the training.

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Design and Implementation of High Efficiency Transceiver Module for Active Phased Arrays System of IMT-Advanced (IMT-Advanced 능동위상배열 시스템용 고효율 송수신 모듈 설계 및 구현)

  • Lee, Suk-Hui;Jang, Hong-Ju
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.7
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    • pp.26-36
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    • 2014
  • The needs of active phased arrays antenna system is getting more increased for IMT-Advanced system efficiency. The active phased array structure consists of lots of small transceivers and radiation elements to increase system efficiency. The minimized module of high efficiency transceiver is key for system implementation. The power amplifier of transmitter decides efficiency of base-station. In this paper, we design and implement minimized module of high efficiency transceiver for IMT-Advanced active phased array system. The temperature compensation circuit of transceiver reduces gain error and the analog pre-distorter of linearizer reduces implemented size. For minimal size and high efficiency, the implented power amplifier consist of GaN MMIC Doherty structure. The size of implemented module is $40mm{\times}90mm{\times}50mm$ and output power is 47.65 dBm at LTE band 7. The efficiency of power amplifier is 40.7% efficiency and ACLR compensation of linearizer is above 12dB at operating power level, 37dBm. The noise figure of transceiver is under 1.28 dB and amplitude error and phase error on 6 bit control is 0.38 dB and 2.77 degree respectively.

Study on Methodology for Effect Evaluation of Information Offering to Rail passengers - Focusing on the Gate Metering Case Study considering congested conditions at a platform - (철도 이용객 정보제공 효과평가 방법론 연구 - 승강장의 혼잡상황을 고려한 Gate Metering 사례 연구 중심으로 -)

  • Lee, Seon-Ha;Cheon, Choon-Keun;Jung, Byung-Doo;Yu, Byung-Young;Kim, Eun-Ji
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.14 no.3
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    • pp.50-62
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    • 2015
  • Recently, Subway Line No. 9, described as a 'hell-like' subway for its recorded load factor of max. 240% due to the opening of the 2nd phase extension section, has been causing problems of recurrent congestion in a subway station building. A recurrent congestion in the station building becomes a factor to offend rail users and to reduce the efficiency of railway management. This study aims to establish the methodology for effect evaluation of information provided to rail users, and conducts a gate metering case study considering the congested conditions at a platform among the methodologies for effect evaluation. The metering effect evaluation by load factor was conducted through selecting the micro simulation and pedestrian simulation tool grafting a gate metering. As a result, it was confirmed that, if gate metering is performed, the service level and pedestrian density of a platform by load factor would improve. In other words, if metering is conducted at a platform, it is possible to control the load factor in the waiting space of a platform. Therefore, it was judged through this study that it is possible to set up the index for effect evaluation of information provided to manage congestion of rail users, and establish the methodology for effect evaluation of information provided to rail users through a program.