• 제목/요약/키워드: Threshold Level

검색결과 1,282건 처리시간 0.028초

젊은 여성의 철분저장 고갈상태와 운동수행능력 (Physical Performance in Young Women with Depleted Iron Stoles)

  • 정영진;정명일;정종귀
    • Journal of Nutrition and Health
    • /
    • 제35권2호
    • /
    • pp.223-228
    • /
    • 2002
  • The purpose of this study was to investigate the relationship between iron deficiency without anemia and physical performance in healthy women aged 20-21 yrs. Ten subjects with normal iron stores (serum ferritin $\geq$ 12$\mu\textrm{g}$/L: iron-sufficient group) and 11 subjects with iron depletion without anemia (serum ferritin < 12 $\mu\textrm{g}$/L and serum hemoglobin > 120 g/L: iron-depleted group) were chosen from a group of 50 women and were given physical-performance tests, including determinations of maximum oxygen consumption (VO$_2$ max) and ventilatory threshold. Iron status assessment included determination of hemoglobin, hematocrit, seam ferritin, total iron-binding rapacity, serum iron and transferrin saturation values. Dietary iron intake was assessed based on seven-day food intake records written by the subjects. Physical activity level was estimated by frequency questionnaires and two-week physical activity records were compiled daily by the subjects. Blood ferritin concentration was significantly lower in the iron-depleted group than in the iron-sufficient group (p < 0.05). However, other variables showing iron status was not different between the groups. There were no significant differences in body size, body composition and physical activity levels between the groups. Daily dietary iron, total protein and animal protein intakes of the iron-sufficient group were significantly higher than those of the iron depleted group. However, no differences were found in the amount of dietary vitamin C and fiber between the groups. The values for VO$_2$max and VO$_2$max corrected with weight or fat-free mass were not different between the groups. However, the ventilatory threshold was significantly higher in the iron sufficient group than in the iron-depleted group. The lower ventilatory threshold in the iron-depleted group suggests that iron depletion without anemia could diminish aerobic physical performance in young women. In addition, a significant correlation of physical performance to serum fferritin level was shown only in the iron depleted group.

원/달러 환율 투자 손실률에 대한 극단분위수 추정 (Extreme Quantile Estimation of Losses in KRW/USD Exchange Rate)

  • 윤석훈
    • Communications for Statistical Applications and Methods
    • /
    • 제16권5호
    • /
    • pp.803-812
    • /
    • 2009
  • 금융자료에 극단값이론을 적용하는 것은 위험관리에서 중요한 최신 통계기법 중의 하나라고 할 수 있다. 극단값분석에서 전통적으로 사용해 오던 연간 최대값방법은 시계열자료의 연간 최대값들에 대하여 일반화 극단값분포를 적합시키는 것이고, 최근 대안으로 널리 사용되고 있는 분계점 방법은 시계열자료 중 충분히 큰 하나의 분계점을 넘어서는 초과값들에 대하여 일반화파레토분포를 적합시키는 것이다. 그러나, 보다 실질적인 방법은 분계점을 넘어서는 초과값들을 하나의 점과정으로 해석하는 것인데, 즉 초과값들의 초과시점과 초과여분을 점근적으로 비동질 포아송과정을 갖는 하나의 2차원 점과정으로 간주하는 것이다. 본 논문에서는 이러한 2차원 비동질 포아송과정 모형을 1982.1.4부터 2008.12.31까지 수집된 원/달러 환율 시계열자료로부터 계산된 일별 환율투자손실률, 즉 일별 로그 손실률에 적용한다. 여기서 주된 관심은 10년 혹은 50년에 한번 정도 발생하는 대형 손실률 수준과 같은 극단분위수를 어떻게 추정하느냐 하는 것이다.

국소 영역별 대비 개선과 쌍선형 보간에 의한 불균등 대비 영상의 효율적 적응 이진화 (An Adaptive Thresholding of the Nonuniformly Contrasted Images by Using Local Contrast Enhancement and Bilinear Interpolation)

  • 정동현;조상현;최흥문
    • 전자공학회논문지S
    • /
    • 제36S권12호
    • /
    • pp.51-57
    • /
    • 1999
  • 본 논문에서는 불균등 대비 영상에서 국소 영역별 대비개선과 문턱치 평면의 쌍선형 보간을 이용한 효과적인 적응 이진화 방법을 제안하였다. 제안한 방법에서는 먼저 영상을 국소 영역으로 나누고, 영역별로 흐리거나 대비가 낮은 부분의 명도차를 증대시켜 전체적으로 대비를 개선한 후, 대비 개선된 국소 영역별 명도 분포로부터 해당 영역의 최적 문턱치를 구하였다. 국소 영역간에 이웃하는 문턱치들을 쌍선형 보간하여 전역적으로 영역별 문턱치들간의 불연속성을 없앰으로써 불균등 대비 영상에 대해서도 관심 영역이나 문자 부분에서의 불연속을 줄이도록 하였다. 불균등 대비를 갖는 일반문서 및 PCB나 웨이퍼상의 문자 영상을 제안한 방법과 기존 방법으로 이진화한 영상들로부터 문자들을 추출하고, 동일 조건하에서 같은 역전파 신경회로망으로 인식 실험하여 제안한 방법의 실효성을 확인하였다.

  • PDF

Long-term Follow-up of Cutaneous Hypersensitivity in Rats with a Spinal Cord Contusion

  • Jung, Ji-In;Kim, June-Sun;Hong, Seung-Kil;Yoon, Young-Wook
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제12권6호
    • /
    • pp.299-306
    • /
    • 2008
  • Sometimes, spinal cord injury (SCI) results in various chronic neuropathic pain syndromes that occur diffusely below the level of the injury. It has been reported that behavioral signs of neuropathic pain are expressed in the animal models of contusive SCI. However, the observation period is relatively short considering the natural course of pain in human SCI patients. Therefore, this study was undertaken to examine the time course of mechanical and cold allodynia in the hindpaw after a spinal cord contusion in rats for a long period of time (30 weeks). The hindpaw withdrawal threshold to mechanical stimulation was applied to the plantar surface of the hindpaw, and the withdrawal frequency to the application of acetone was measured before and after a spinal contusion. The spinal cord contusion was produced by dropping a 10 g weight from a 6.25 and 12.5 mm height using a NYU impactor. After the injury, rats showed a decreased withdrawal threshold to von Frey stimulation, indicating the development of mechanical allodynia which persisted for 30 weeks. The withdrawal threshold between the two experimental groups was similar. The response frequencies to acetone increased after the SCI, but they were developed slowly. Cold allodynia persisted for 30 weeks in 12.5 mm group. The sham animals did not show any significant behavioral changes. These results provide behavioral evidence to indicate that the below-level pain was well developed and maintained in the contusion model for a long time, suggesting a model suitable for pain research, especially in the late stage of SCI or for long term effects of analgesic intervention.

Monosodium Glutamate의 맛표현 용어와 기본맛 성분과의 상호작용에 관한 연구 (Studies on the Taste Describing Terms of Monosodium Glutamate and the Interactions Between MSG and Other Basic Taste Substances)

  • 홍혜경;이현덕;이철호
    • 한국식생활문화학회지
    • /
    • 제5권4호
    • /
    • pp.425-430
    • /
    • 1990
  • MSG의 맛 표현용어를 설문조사를 통하여 수집분석하고 관능검사를 통한 MSG의 감응역가를 다른 기본 맛의 역가와 비교하였으며, MSG가 다른 기본 맛 성분에 첨가되었을때 일어나는 맛의 강도변화를 관능적 방법으로 측정하였다. 96명의 설문 응답자로부터 수집분석한 자료에 의하면 MSG 자체의 맛은 느끼한 맛(58%)과 역겨운 맛(24%)으로 주로 표현되었으나 음식에 첨가됨으로써 기대 되는 맛은 감칠 맛(79%)으로 주로 표현(表現)되었다. 관능검사자들이 MSG 수용액을 직접 맛보고 표현한 용어로는 최소 감각농도 부근의 낮은 농도에서는 느끼한 맛, 쓴맛, 단맛 등이 감지되었으나 최소 감미농도 이상에서는 느끼한 맛과 짠맛이 주로 표시되었다. MSG 수용액의 최소 감각농도는 0.002mole 수준이었으며 최소 감미농도는 0.006mole 수준이었다. MSG와 기본 맛 성분(成分)과의 상호작용을 보면 MSG가 식염용액에 첨가되면 짠맛의 상승작용을 나타내었다. 그러나 MSG가 설탕용액에 첨가되면 첨가된 MSG 농도가 낮은 때(0.01M)에는 다소 단맛의 상승효과를 나타내었으나 MSG 농도가 높아지면 단맛의 억제효과를 나타내었다. MSG를 구연산용액에 첨가했을 때는 전반적으로 신맛의 억제효과가 나타났다.

  • PDF

스마트폰 시청 시 몸통 교정기 착용에 따른 목, 허리 굽힘-이완 비율, 관절가동범위, 압통, 착용감 변화 (Changes in the Cervical and Lumber Flexion-Relaxation Ratio, Range of Motion, Pressure Pain Threshold, and Perceived Comfort Following the Wearing of a Trunk Brace during Smartphone Watching)

  • 박진성;박두진
    • PNF and Movement
    • /
    • 제19권3호
    • /
    • pp.413-422
    • /
    • 2021
  • Purpose: This study was conducted to investigate changes in the cervical and lumbar flexion-relaxation ratio, range of motion, pressure pain threshold, and perceived comfort following the wearing of a trunk brace during smartphone watching. Methods: To calculate the number of subjects for this study, an analysis with G*Power was performed at a statistical power of 0.8, an effect size of 0.5, and a significance level of 0.05, based on the results of a preliminary experiment on five subjects. In total, 27 adult men and women were recruited who had been informed of the study's purpose and process and had agreed to participate. All subjects watched content on a smartphone for 20 minutes in the same posture and conditions while wearing and not wearing a trunk brace, and then their cervical and lumbar flexion-relaxation ratio, range of motion, pressure pain threshold, and perceived comfort were measured. Results: Compared to the non-wearing of a trunk brace, the wearing of a trunk brace resulted in a statistically significant smaller decline in cervical extension and right-side cervical rotation (p<0.05). When the subjects wore a trunk brace, their right- and left-side cervical and right-side lumbar pressure pain statistically significantly improved when compared to not wearing a trunk brace (p<0.05). They also perceived a significantly lowered level of comfort 20 minutes after wearing a trunk brace compared to immediately after wearing it (p<0.05). Conclusion: The trunk brace was effective in reducing declines in right-side cervical rotation and the occurrence of left- and right-side cervical and right-side lumbar pressure pain. The findings indicate the need to improve the perceived comfort of trunk braces.

Masking Level Difference: Performance of School Children Aged 7-12 Years

  • de Carvalho, Nadia Giulian;do Amaral, Maria Isabel Ramos;de Barros, Vinicius Zuffo;dos Santos, Maria Francisca Colella
    • Journal of Audiology & Otology
    • /
    • 제25권2호
    • /
    • pp.65-71
    • /
    • 2021
  • Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.

Masking Level Difference: Performance of School Children Aged 7-12 Years

  • de Carvalho, Nadia Giulian;do Amaral, Maria Isabel Ramos;de Barros, Vinicius Zuffo;dos Santos, Maria Francisca Colella
    • 대한청각학회지
    • /
    • 제25권2호
    • /
    • pp.65-71
    • /
    • 2021
  • Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.

저온 Poly-Si TFT를 이용한 저소비전력 레벨 쉬프터 (A Low-Power Level Shifter Using Low Temperature Poly-Si TFTs)

  • 안정근;최병덕;권오경
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2005년도 추계종합학술대회
    • /
    • pp.747-750
    • /
    • 2005
  • In this paper, we propose a new level shifter circuit for reducing power consumption. The concept of the proposed level shifter is to use capacitive coupling effect to reduce short circuit current. The power consumption of the proposed level shifter is reduced up to 50%, compared to the conventional level shifter. Especially the proposed level shifter circuit works well with low temperature poly-Si (LTPS) TFTs. It can operate on low input voltage even with low-mobility, high and widely-varying threshold voltage of LTPS TFT.

  • PDF

오이 시설재배시 고구마뿌리혹선충의 경제적피해한계 (Economic Threshold of Meloidogyne incognita for Greenhouse Grown Cucumber in Korea)

  • 김동근;이중환
    • 식물병연구
    • /
    • 제14권2호
    • /
    • pp.117-121
    • /
    • 2008
  • 고구마 뿌리혹선충(Meloidogyne incognita)의 시설재배 오이에 대한 경제적 피해한계를 조사하기 위하여 비닐하우스 내에 합판으로 만든 박스($30{\times}40{\times}15cm$)를 묻고 박스 내 토양 $100cm^3$당 뿌리혹선충 유충의 밀도를 0, 10, 30, 100, 300, 600마리로 조정된 토양을 넣었다. 각 박스에는 '장수신토좌'에 접붙인 '슈퍼만촌'오이 23일 묘를 8월 1일 1포기씩 심고 11월까지 각 구당 오이 수확량을 조사하였다. 뿌리혹선충의 유충밀도와 수량과의 회귀식은 $Y=0.82-0.04{\cdot}Log_{10}$(Pi+1)로 방제 비용을 감안한 경제적 피해 허용 수준은 정식전 뿌리혹선충 유충의 밀도가 토양 $1,000cm^3$당 5마리이면 살선충제 입제 살포가 경제적이고, 유충의 밀도가 토양 $1,000cm^3$당 25마리 이상이면 훈증제를 처리하는 것도 고려해 볼 수 있다. 오이 시설재배시 뿌리혹선충의 피해를 방지하기 위해서는 최소한 정식 수개월 전에 미리 토양 선충 밀도를 조사해야 할 것이다.