• 제목/요약/키워드: Median Frequency

검색결과 458건 처리시간 0.026초

저작근의 근전도 휴지기와 근육피로와의 관계 (A Relationship Between the EMG Silent Period and Muscle Fatigue of the Masticatory Muscle)

  • 김태훈;양덕진;강병길;조일준;이진;김성환
    • 대한전기학회논문지:시스템및제어부문D
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    • 제50권5호
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    • pp.247-254
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    • 2001
  • Silent period(SP) is transient stops of muscle activity that are induced by mechanical or electrical stimulus and the duration of silent period is a important parameter that have been associated with symptoms of masticatory dysfunction. Muscle fatigue is induced by sustained muscular contractions. It is associated with the external manifestations as the inability to maintain a desired force output, muscular tremor, and localized pain. Muscle fatigue is a parameter that have been measured or monitored the deterioration of a performance of muscles. On the study of relationship between SP and masticatory muscle fatigue, Nagasawa suggested that SP increases up to 3 min. from the beginning of clenching when the subjects performed sustained contractions at 50% maximum clenching level. In this paper, in order to evaluate a relationship between SP and muscle fatigue, 10 SPs per 1 minute are measured at 10%, 20%, 50% maximum clenching level. We used the median frequency in order to quantify the degree of muscle fatigue. However, the results shows that the duration of silent period was not significantly affected by differing levels of muscle fatigue. Therefore, we suggest that the SP is not increased or decreased as the results of muscle fatigue, also the origin of the SP generation mechanism is discussed.

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성인여성의 성역할 정체감에 따른 신체 및 화장이미지 (Body Image and Cosmetic Image Based on Women's Sex Role Identity)

  • 김용숙
    • 복식
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    • 제59권3호
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    • pp.55-56
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    • 2009
  • The purpose of this study was to analyse body and cosmetic image according to women's sex role identity. The subjects of this study were 433 women over 20 years old. Self-administered questionnaires were used for data collection. SPSS(Ver. 15.0) was used for mean, median, frequency, percentages, factor analysis, and one-way ANOVA. The results of this study were as followed; First, women were clustered into 4 groups according to their sex role identity. 36.5% was classified as an androgynous group, 32.4% was a undifferentiated group, 16.1% was a masculine group, and 15.0% was a feminine group. Second, factors of women's body image were interest in appearance, interest in weight, and charming of appearance. Factors of cosmetic image were natural & sociable, urban & intellect, passionate, romantic, prestige & sophisticate, fashionable & splender, active, feminine, and formal. Third, Androgynous group showed much interests in appearance and charming of appearance, but undifferentiated group had low interests. Androgynous group pursued natural & sociable, urban & intellect, passionate, romantic, prestige & sophisticate, fashionable & splendor, active, feminine, and formal images most when they applied make-ups. Masculine group pursued urban & intellect and active images much and femme group pursued natural & sociable, feminine, and formal images much. However undifferentiated group pursued all factors of cosmetic images less. Forth, androgynous group applied more kinds of cosmetics, but undifferentiated group applied less.

Frequency of Post-Concussion Syndrome in Korean Patients with Minor Head Injury

  • Lee, Ji Young;Yoon, Young Hoon;Lewis, Roger J.;Tolles, Juliana
    • Journal of Trauma and Injury
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    • 제30권2호
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    • pp.41-46
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    • 2017
  • Purpose: To determine the incidence of post-concussion syndrome (PCS) in Korean patients after minor traumatic brain injury. Methods: We conducted an observational cohort study of a convenience sample of patients presenting to the emergency department of a major academic Korean hospital. Patients who visited the Emergency Department for head trauma were screened. A researcher questioned the subject regarding his or her symptoms. Subjects were contacted by phone approximately 2 weeks after their Emergency Department visit and questioned about subsequent symptoms and subsequent visits for medical care. Results: Only 8% of subjects reported any post-concussion symptoms. Only 0.4% had three or more symptoms which might have met criteria for PCS. The median peak onset of symptoms was 3 days after injury. Conclusion: The incidence of PCS is Korean patients is much lower than that documented for patients in the United States or other western countries. On the other hand, this study results could give an idea that mild trauma could also cause the PCS. Further study is needed to replicate this finding and investigate possible explanations for this difference.

An eigenspace projection clustering method for structural damage detection

  • Zhu, Jun-Hua;Yu, Ling;Yu, Li-Li
    • Structural Engineering and Mechanics
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    • 제44권2호
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    • pp.179-196
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    • 2012
  • An eigenspace projection clustering method is proposed for structural damage detection by combining projection algorithm and fuzzy clustering technique. The integrated procedure includes data selection, data normalization, projection, damage feature extraction, and clustering algorithm to structural damage assessment. The frequency response functions (FRFs) of the healthy and the damaged structure are used as initial data, median values of the projections are considered as damage features, and the fuzzy c-means (FCM) algorithm are used to categorize these features. The performance of the proposed method has been validated using a three-story frame structure built and tested by Los Alamos National Laboratory, USA. Two projection algorithms, namely principal component analysis (PCA) and kernel principal component analysis (KPCA), are compared for better extraction of damage features, further six kinds of distances adopted in FCM process are studied and discussed. The illustrated results reveal that the distance selection depends on the distribution of features. For the optimal choice of projections, it is recommended that the Cosine distance is used for the PCA while the Seuclidean distance and the Cityblock distance suitably used for the KPCA. The PCA method is recommended when a large amount of data need to be processed due to its higher correct decisions and less computational costs.

One portion size of foods frequently consumed by Korean adults

  • Choi, Mi-Kyeong;Hyun, Wha-Jin;Lee, Sim-Yeol;Park, Hong-Ju;Kim, Se-Na;Song, Kyung-Hee
    • Nutrition Research and Practice
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    • 제4권1호
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    • pp.82-88
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    • 2010
  • This study aimed to define a one portion size of food items frequently consumed for convenient use by Koreans in food selection, diet planning, and nutritional evaluation. We analyzed using the original data on 5,436 persons (60.87%) aged 20~64 years among 8,930 persons to whom NHANES 2005 and selected food items consumed by the intake frequency of 30 or higher among the 500 most frequently consumed food items. A total of 374 varieties of food items of regular use were selected. And the portion size of food items was set on the basis of the median (50th percentile) of the portion size for a single intake by a single person was analyzed. In cereals, the portion size of well polished rice was 80 g. In meats, the portion size of Korean beef cattle was 25 g. Among vegetable items, the portion size of Baechukimchi was 40 g. The portion size of the food items of regular use set in this study will be conveniently and effectively used by general consumers in selecting food items for a nutritionally balanced diet. In addition, these will be used as the basic data in setting the serving size in meal planning.

등장성 운동 시 근전도 중앙주파수 데이터의 잡음 제거 방법 (Noise Reduction Methods for the EMG Median Frequency Data in Fatiguing Isotonic Exercise)

  • 조상현
    • 한국전문물리치료학회지
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    • 제8권4호
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    • pp.31-43
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    • 2001
  • 19명의 건강한 성인 남자의 우세팔쪽 위팔두갈래근에서 피로가 생길 때까지 2.4초를 하나의 주기로 팔꿉을 반복적 등장성으로 굽히고 펴서 표면근전도 신호를 얻었다. 처리과정 A 중앙주파수(MDF )는 이 신호의 0.5초 구간을 power spectrum analy sis (PSA)로 계산하였는데 상당량의 잡음이 있었다. 중앙주파수의 잡음 양을 비교하기 위해, 동일한 표면근전도에서 3번까지 신호를 받았다 (2.4초 구간을 PSA로 계산한 처리과정 B, 13 point 로 moving averages한 처리과정 C, digital low pass filter한 처리과정 D). 그리고 나서 그 신호의 주요 주파수 성분을 뽑아내었다. 위의 중앙주파수 자료와 시간간의 회귀직선을 분석하면 초기 중앙주파수, 회귀기울기, 그리고 피로지수와 같은 모수를 얻을 수 있다. 비모수 검정의 하나인 Kendall 기법으로 네 개의 처리과정간의 모수를 비교하였다. 통계결과 잡음이 처리과정 A보다 B, C, D에서 적었고, D에서 가장 적게 나타났다. 중앙주파수를 digital low pass로 여과(filtering)함으로써 앞으로 있게 될 동적 운동 시 근피로 모니터기의 신뢰도를 높일 수 있다.

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기준전극의 형상과 입력전극사이의 간격을 고려한 건식형 표면 근전위 센서 개발 (Development of Dry-type Surface Myoelectric Sensor for the Shape of the Reference Electrode and the Inter-Electrode Distance)

  • 최기원;최규하
    • 대한전기학회논문지:시스템및제어부문D
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    • 제55권12호
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    • pp.550-557
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    • 2006
  • This paper proposes a dry-type surface myoelectric sensor for the myoelectric hand prosthesis. The designed surface myoelectric sensor is composed of skin interface and processing circuits. The skin interface has one reference and two input electrodes, and the reference electrode is located in the center of two input electrodes. In this paper is proposed two types of sensors with the circle- and bar-shaped reference electrode, but all input electrodes are the bar-shaped. The metal material of the electrodes is the stainless steel (SUS440) that endures sweat and wet conditions. Considering the conduction velocity and the median frequency of the myoelectric signal, the inter-electrode distance (IED) between two input electrodes as 18mm, 20mm, and 22mm is selected. The signal processing circuit consists of a differential amplifier with a band pass filter, a band rejection filter for rejecting 60Hz power-line noise, amplifiers, and a mean absolute value(MAV) circuit. Using SUS440, six prototype skin interface with different reference electrode shape and IED is fabricated, and their output characteristics are evaluated by output signal obtained from the forearm of a healthy subject. The experimental results show that the skin interface with parallel bar shape and the 18mm IED has a good output characteristics. The fabricated dry-type surface myoelectric sensor is evaluated for the upper-limb amputee.

Mitochondrial DNA Variation and Genetic Relationships in Japanese and Korean Cattle

  • Sasazaki, S.;Odahara, S.;Hiura, C.;Mukai, F.;Mannen, H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권10호
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    • pp.1394-1398
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    • 2006
  • The complete mtDNA D-loop regions of Japanese and Korean cattle were analyzed for their mtDNA variations and genetic relationships. Sequencing the 30 Higo substrain and 30 Tosa substrain of Japanese Brown, respectively 12 and 17 distinct Bos haplotypes were identified from 77 polymorphic nucleotide sites. In order to focus on the relationships among Japanese and Korean cattle, two types of phylogenetic tree were constructed using individual sequences; first, a neighbor-joining tree with all sequences and second, reduced median networks within each Japanese and Korean cattle group. The trees revealed that two major mtDNA haplotype groups, T3 and T4, were represented in Japanese and Korean cattle. The T4 haplogroup predominated in Japanese Black and Japanese Brown cattle (frequency of 43.3-66.7%), while the T3 haplogroup was predominant (83.3%) and T4 was represented only twice in the Korean cattle. The results suggested that the mitochondrial origins of Japanese Brown were Japanese ancient cattle as well as Japanese Black in despite of the considerable introgression of Korean and European cattle into Japanese Brown.

상악 정중 과잉치의 위치와 병발증간의 관계 (The relationship between the position of mesiodens and complications)

  • 정연화;나경수;조봉혜
    • Imaging Science in Dentistry
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    • 제38권2호
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    • pp.103-107
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    • 2008
  • Purpose: The purpose of this study was to evaluate the relationship between the position of mesiodens and its complications. Materials and Methods: The subjects for this study consisted of 172 patients with mesiodens. Panoramic radiographs and cross-sectional tomography were taken of all of the subjects. Their clinical records and radiographs were analyzed in order to study the direction and vertical and sagittal position of mesiodens, as well as complications caused by mesiodens. Results: The number of mesiodens was one in 112 cases (65.1%) and two in 60 cases (34.9%). Complications were found in 121 mesiodentes (52.2%), with being median diastema the most frequent. The incidence of complications was high in erupted mesiodens (75.0%), in horizontal mesiodens (89.8%) and in mesiodens located within the arch (75.7%), but was low in mesiodens impacted above apex (29.8%), in normal position (34.4%) and in palatally positioned mesiodens (46.5%). Conclusion: It was suggested that the frequency of complications was different according to the vertical position, the direction of the crown and the sagittal position.

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청소년기 자녀를 둔 한부모가족의 모자녀갈등, 대처와 심리적 안녕 (Single Mother Family's Mother-Adolescent Conflicts, Copings and Psychological Well-being)

  • 김오남
    • 한국생활과학회지
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    • 제13권4호
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    • pp.507-519
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    • 2004
  • The purpose of this study is to explore the general trends and the correlations of parent-child conflicts, copings, and psychological well-being of single mothers and their children, and to analyze the variables explaining relationships between single mothers and their children. The subjects were 196 dyads of single mothers and their children who reside in Gwangju city and Jeonnam area. The data were analyzed with frequency, t-Test, Pearsons' r, and multiple regression by SPSS. The major findings are as follows: 1. Scores of single mothers and their children had conflicts and emotion-focused copings lower than median. Another scores of single mothers and their children had significantly higher problem solving focused copings and emotion-focused copings than their children except life satisfaction; 2. Conflicts, copings, life satisfaction, and depression of a single mother were positively related to those of children; 3. Life satisfaction of single mothers depends on the reason for spouse-loss, their own education background, and problem solving-focused copings. Also, that of children depends on problem solving-focused copings, mother-child conflicts, and the mothers' education. Depression of single mothers is dependent upon mother-child conflicts, emotion-focused copings, and mothers' education. Also, that of children is upon mother-child conflicts, emotion-focused copings, mothers' education, and problem solving-focused copings.

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