• Title/Summary/Keyword: Time-Frequency Analysis

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Evaluation of the change in Geotechnical properties due to the Construction of Civil engineering Structure using HWAW Method (HWAW방법을 이용한 토목구조물 건설에 따른 하부 지반 물성 변화 평가)

  • Park, Hyung-Choon;Noh, Hee-Kwan;Park, Byeong-Cheol;Kim, Min-Su
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.182-187
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    • 2010
  • In the various fields of Civil Engineering, shear modulus is very important input parameters to design many constructions and to analyze ground behaviors. In general, a shear wave velocity profile is decided by various experiments before constructing a structure and, analysis and design are carried out by using decided shear wave velocity profile of the site. However, if civil structures are started to construct, the shear wave velocity will be increased more than before constructions because of confining pressure increase by the load of structure. The evaluation of the change in shear wave velocity profile is used very importantly when maintaining, managing, reinforcing and regenerating existing structures. In this study, a non-destructively geotechnical investigation method by using the HWAW method is applied to an evaluation of change in properties of the site according to construction. Generally, the space for experiments is narrow when underground of existing or on-going structures is evaluate, so a prompt non-destructive experiment is required. This prompt non-destructive experiment would be performed by various in-situ seismic methods. However, most of in-situ seismic methods need more space for experiments, so it is difficult to be applied. The HWAW method using the Harmonic wavelet transforms, which is based on time-frequency analysis, determines shear wave velocity profile. It consists of a source as well as short receiver spacing that is 1~3m, and is able to determine a shear wave velocity profile from surface to deep depth by one test on a space. As the HWAW method uses only the signal portion of the maximum local signal/noise ratio to determine a profile, it provides reliability shear modulus profile such as under construction or noisy situation by minimizing effects of noise from diverse vibration on a construction site or urban area. To estimate the applicability of the proposed method, field tests were performed in the change of geotechnical properties according to constructing a minimized modeling bent. Through this study, the change of geotechnical properties of the site was effectively evaluated according to construction of a structure.

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The Adolescents' Internet Addiction Tendencies According to their Human Resources (청소년의 인적 자원에 따른 인터넷 중독 경향성)

  • Song, Keum-Sook;Jang, Yoon-Ok
    • Journal of Korean Home Economics Education Association
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    • v.17 no.3 s.37
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    • pp.1-15
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    • 2005
  • The purpose of this study was to investigate adolescents' internet addiction tendencies according to their human resources which is composed of personal resources and interpersonal resources. The subjects of this study were 396 middle school students in Daegu. Analysis of data were done with the use of frequency. percentage, meat factor analysis, and MANOVA with the Scheffe test applied. The main results of this study were as follows : First, there were meaningful differences in adolescents' internet addiction tendencies according to their personal resources such as self-control ability, Problem-solving ability, and time management ability. Second, there were meaningful differences in adolescents' internet addiction tendencies according to their interpersonal resources such as parents-support, peer-support, and teacher-support.

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Comparison of Stress Between the Mother and Father Who Have Children (운동발달장애아 어머니와 아버지의 스트레스 비교)

  • Song, Ju-Young
    • Physical Therapy Korea
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    • v.5 no.2
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    • pp.65-80
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    • 1998
  • Parents of handicapped children are experiencing difficulties in their children's care, social isolation, change of life style and lirnited leisure time. Because the parents should take care of the children's daily life, they have lots of psychological and physical stress. Chronic stress of parents puts stress to the other family members and affects the development of children with handicap. The purpose of this study were to identify the level of stress in each of parents of children with motor problem, the characteristics of the children and general information related with the children, and to analyse the stress by reasons. Specially organized questionnaire were used for an investigation method. "Test of stress in mother who has children with chronic illness" by Kim Hee-soon were modified and used. The questionnaire answered by 43 mothers and 35 fathers were analyzed. Data analysis includes frequency analysis, Pearson correlation coefficients, paired-samples t-test and MANOV A by SPSSWIN. The results were as follows: 1) Degree of handicap was most moderate (46.5%), level of motor development was most pull to walk (34.9%), and combined handicap was 69.8%. 2) Sexual distribution represented that 51.2% male and 48.8% female. The cost of physical therapy was 69.8% in no more than 100,000 won. 3) The mean of age, for the mother was 32.8 years and 35.3 years. Level of motor development that mother and father expect was 88.4%, 83% walk alone. 4) Both mother and father experienced stress in other of Part II (changes in father was the illness status of the child and difficulty in taking care of child), Part III (prognosis of the child's condition), Part I (social-personal relationships and the responsibility of the care givers). In the total score of stress, mother's stress is indicated higher level than father's stress. 5) There was no correlationship between characteristics and stress of mother and father. 6) There was no statistically significant difference between characteristics and related general information of children with handicap and stress of mother and father. As a results, the mother of children with handicap are experiencing more stress than the father. Both of parents have the most difficulties in the changes in the illness status of the child and difficulty in taking care of child. This study can be used as resources of education, therapy and counselling for children with handicap and their parents. This study, also, can be used to encourage the quality of Iife for the children with handicapped and their family.

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An Analysis of the Instructional State of the Unit 생Small Living Things′ in the Elementary School Science (초등학교 자연과 생작은생물생 단원의 수업 실태 분석)

  • 최도성;최규식;남철우;김정길;김석중;송판섭;한광래;한효의
    • Journal of Korean Elementary Science Education
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    • v.19 no.1
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    • pp.157-170
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    • 2000
  • The purpose of this study is to survey the instructional state of the unit 'Small Living Things' in the Elementary School Science. for this study, 100 teachers were surveyed on teaching-learning practices. More specifically, questions were asked on the degree of accomplishing instruction objectives, frequency of field . study, experimental preparation, alternative instructional methods, amount of preparation, availability of reference books for teachers and availability of information materials on the Kwangju region. Our results show that teachers find the objectives related to the collection of living things for class experiments and the task of growing and observing them the most difficult to accomplish. It was reported that 38% of teachers have actually conducted field trips. The obstacles listed in going out on field study range from lack of knowledge of appropriate places, lack of time, to safety concerns. The most difficult problem in teaching this unit was preparing proper instructional materials, regardless of teacher's gender, career, and interest. Most respondents let children provide the experimental subjects. Teachers with collection experience tend to provide for the experimental materials themselves. Our Analysis also reveals that more than 70% of the respondents do not have adequate knowledge of the species dealt with in the unit. Gender, career, and interest area of the teachers did not make any difference (p< .05). In the case that proper experimental subjects have not been prepared, VTR, textbooks, and charts were reported as the most frequently used alternative instruction aids. The level of content and amount of knowledge contained in this unit were found to be appropriate. Information on instruction materials and experiment-observation were obtained through the teaching manual or periodicals (58%), information materials on the region(20%), and fellow teachers (12%). Reference books for teachers and materials on the region are perceived to be inadequate in order of importance in the areas of preparation method, level-wise learning guide, experimental observation, and information on species covered in text. Overall, it was judged that the highest concern was with obtaining experimental materials, and teacher's reference books and materials on the region need to be reinforced to allow teachers to more fully utilize them. Development and distribution of proper instruction-learning materials to the children's level is also required.

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A Content Analysis of Storytelling in Mathematics Textbooks & Research on the Actual Teacher-Student Condition centered on Senior High School (수학교과서의 스토리텔링 내용 분석 및 활용실태조사 - 고등학교 1학년 중심으로 -)

  • Kang, Ok-Sun;Kim, Yunghwan
    • Journal of the Korean School Mathematics Society
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    • v.17 no.3
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    • pp.337-358
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    • 2014
  • The purpose of this study is to investigate how storytelling is embodied in the Mathematics I textbooks for first grade high school students in the 2009 revised curriculum and the perception of secondary math teachers and students of those books. Furthermore, in order to have some implications on newly ongoing textbook development, this thesis sets up the following goals for inquiry into the effect on storytelling. First, are there any noticeable differences among the 10 types of mathematics I textbooks for high school first graders in the 2009 revised curriculum? Second, what do teachers and students think of textbooks which apply storytelling techniques? The results are as follows. The frequency of storytelling types that appeared in the textbooks is as follows: real-life connection type and inter-scholarship type take up 47.55% and 24.51% respectively, followed by decision-making type with 10.52%, math history type with 10.17% and tool-using type with 7.05%. Within the contents, math history type showed up on reading material from every textbook. And it is worth considering that real-life-connection type has the most various topics and is mainly for arousing interest and checking up on some concepts. However, inter-scholarship type is usually related to science, and decision-making type is included for error analysis and tool-using type for reading materials about math programs. The results of this study suggest that many of the teachers who participated showed some kind of understanding of storytelling but there were not many who are actually incorporating that into their own classes. It is also essential that we develop textbooks that are effective for storytelling classes, hold regular symposiums as well as teacher training, and create tools for proper assessment. Furthermore, students think that textbooks based on storytelling would have positive effects as long as they are supported by enough time, a sufficient number of classes and tests with validity.

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Relationships between Health, Depression, Memory Self-Efficacy and Metamemory in Adults (성인의 건강, 우울, 기억, 자기효능과 메타기억과의 상관관계 연구)

  • Kim, Jeong-Hwa;Kang, Hyun-Sook
    • The Korean Journal of Rehabilitation Nursing
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    • v.1 no.1
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    • pp.61-71
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    • 1998
  • Defining prediction variables related to metamemory for the adults in aging process has worthwhile meaning from the perspective that the produced results can be helpful to reducing the difficulty of memorizing efforts and it can also enhance quality of life of aged. This study attempted to analysis relationship between perceived health status, depression, memory self-efficacy and meta memory for the subjects of middle age and old age adults. This study was designed by adopting descriptive correlational analysis method for the 468 middle and old age adults who are living in Seoul. Samples were selected by convenience sampling. Data collection was done over 1 month period in june 1998. The instruments used in this study were health status measuring scale including depression measuring scale, memory self efficacy measuring scale and metamemory measuring scale which were verified for reliability. Data collected were analized by using SPSS for frequency, Peason correlation, t-test and ANOVA according to the variables character and the study purposes. Results of the study were as follows. 1. Relationship between perceived health status, depression, memory self-efficacy and metamemory. Relational analyses between perceived health status, depression, memory self-efficacy and metamemory supported the hypotheses of 1st, 2nd and 3rd(p < .01). These results suggested that the aged perceived great health status then their memory self-efficacy, and metamemory showed the high scores. In the case of depression when its level became decreased metamemory was inclined to increased. Thus, it is identified that strong relationship exists between these variables. 2. Perceived health status, depression, memory self-efficacy by subject's general characteristics. Scores of perceived health status were high in the group of man compared to the group of women, and also highly educated group showed great perceived health status. Group of persons having occupation showed high score of perceived health status and low depression score. The score of memory self-efficacy and metamemory showed higher in the middle aged than the old aged. The high scores of memory self-efficacy and metamemory were found in the group of highly educated people and who have continuing education. The high scores of memory self-efficacy were found in the group of persons having their job and high metamemory scores found in the group of persons having religion. In summary, the greater perceived health status and memory self-efficacy, the more metamemory scores were likely increased and the more depression level was decreased, the more metamemory was likely increased. Also it was found that general characteristics like educational level, continuing education and religion influenced the metamemory of the aged. Therefore, prevention the aged from getting depression and activation of health promotion are needed to delay time of memory loss.

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Analysis of Solar Irradiance Measurement From a Multi-Filter Radiometer At Kwangju, South Korea.

  • Ogunjobi, K.O.;Kim, Y.J.;He, Z.;Ryu, S.Y.
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2001.11a
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    • pp.335-335
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    • 2001
  • Direct-normal, total horizontal and diffuse horizontal irradiance data obtained from a multi-filter rotating shadowband radiometer over seven different wavelength bands (416nm, 151nm, 616nm, 675nm, 870nm and 940nm and the entire spectrum) has been analyzed at Kwangju, South Korea from June 1998 December 2000. The maximum hourly global radiation flux ranged from 0.44 MJ/$m^2$ to 2.68 MJ/$m^2$ at around 11:00-12:00 Hr local time while the maximum hourly diffuse radiation flux ranged from about 0.96 MJ/$m^2$ to 1.37 MJ/$m^2$. The maximum hourly direct irradiance ranged from 1.42 MJ/$m^2$ to 2.92 MJ/$m^2$ from June1998-2000. During the period under consideration, the average monthly global radiation recorded were 13.09 MJ/$m^2$/day, 10.58MJ/$m^2$/day and 9.78MJ/$m^2$/day for years 1998, 1999 and 2000 respectively, while the diffuse irradiance were 6.54 MJ/$m^2$/day, 5.33 MJ/$m^2$/day and 5.14 MJ/$m^2$/day for f998, 1999 and 2000 respectively. The direct irradiance values at the site were 11.63 MJ/$m^2$/day, 8.24MJ/$m^2$/day and 7.75 MJ/$m^2$/day for 1998, f999 and 2000 respectively. It was observed that each of the years has its own unique meteorological parameters that affect the quality and quantity of radiation received for each month. The annual average daily fractions of the diffuse to the global radiation (KD) were 0.51, 0.61 and 0.59 for years 1998, 1999 and 2000 respectively. Analysis indicated that the average daily KD ranged from 0.13 to a maximum value of 0.99 in May for irradiance measured at the broadband channel while the maximum and minimum KD value of 0.91 and 0.23 was recorded at wavelength band 870nm and 940nm in January and September respectively. The lowest average daily clearness index (Kt) value recorded was 0.03 in May (Spring) and the annual average daily clearness indexes are 0.45, 0.34 and 0.35 for years 1998, f999 and 2000 respectively. The frequency of clear days annually at Kwangju is 67.95%, 29.57% and 40.72% for years 1998, 1999 and 2000 respectively.

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Analysis of High-Resolution Manometry Results in LPRD Patients Who Do Not Response to PPI Medication (양자펌프 억제제에 반응을 보이지 않은 인후두 역류질환 환자에서 고해상도 식도 내압검사의 분석)

  • Lee, Chang-Hee;Lee, Hyun-Sub;Jin, Sung-Min;Lee, Sang-Hyuk
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.23 no.1
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    • pp.43-47
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    • 2012
  • Background and Objectives : Laryngopharyngeal reflux disease (LPRD) originates from regurgitation of gastric contents to the laryngopharynx, and it is relatively common disease in otolaryngology. Proton-pump inhibitor (PPI) medication is frequently using treatment method in present time, but controversies exist regarding treatment for it. High-resolution manometry (HRM) system is a newly developed device that using 36 channels and pressure topography plotting program, checking the function and status of esophagus. The aim of this study was to evaluate clinical usefulness of HRM in LPRD patients who do not response to PPI medication. Materials and Method : From July 2009 to July 2010, a total of 99 patients who were suspected LPRD according to symptoms (Reflux Symptom Index >13) and laryngoscopic findings (Reflux Finding Score >7) were retrospectively enrolled in this study. Patients were consisted of 31 men and 68 women, the mean age was 51.8 years, the mean BMI was 22.46. Patients have taken PPI medication for 2 months, after medication, they performed HRM. Comparative analysis was performed with results of the difference in symptoms. Results : In 99 patients, 37 patients (37.4%) show not improvement of LPRD symptoms after PPI medication. Among them, 18 patients (48.6%) showed abnormal findings that were classified as Peristaltic dysfunction (38.9%), Diffuse esophageal spasm (11.1%), Relaxation impairment of LES (11.1%), Achalasia (5.6%), Hypotensive LES (11.1%), Relaxation impairment of UES (11.1%), Nutcracker esophagus (5.6%), Decreased resting pressure (5.6%). Other 62 patients (62.6%) show improvement of LPRD symptoms, 23 patients (37.1%) showed abnormal findings. Most common finding was Peristaltic dysfunction (43.4%) More prevalent abnormal findings of HRM were found in patients who revealed no response to PPI medication (48.6% vs. 37.1%), but it does not reach the statistical significance. Conclusion : Although statistical significances is not showed, the difference observed in the frequency of HRM abnormal finding between response and no response for PPI medication. It has been estimated that HRM may be used to determine differential diagnosis in patients with LPRD. Further studies in lager population containing normal controls will be needed to prove clinical usefulness.

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Analysis of High-Resolution Manometry Results in LPRD Patients who do not Response to PPI Medication (양자펌프 억제제에 반응을 보이지 않은 인후두 역류질환 환자에서 고해상도 식도 내압검사의 분석)

  • Lee, Chang-Hee;Lee, Hyun-Sub;Jin, Sung-Min;Lee, Sang-Hyuk
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.22 no.2
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    • pp.151-155
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    • 2011
  • Background and Objectives : Laryngopharyngeal reflux disease (LPRD) originates from regurgitation of gastric contents to the laryngopharynx, and it is relatively common disease in otolaryngology. Proton-pump inhibitor (PPI) medication is frequently using treatment method in present time, but controversies exist regarding treatment for it. High-resolution manometry (HRM) system is a newly developed device that using 36 channels and pressure topography plotting program, checking the function and status of esophagus. The aim of this study was to evaluate clinical usefulness of HRM in LPRD patients who do not response to PPI medication. Subjects and Method : From July 2009 to July 2010, a total of 99 patients who were suspected LPRD according to symptoms (Reflux Symptom Index >13) and laryngoscopic findings (Reflux Finding Score >7) were retrospectively enrolled in this study. Patients were consisted of 31 men and 68 women, the mean age was 51.8 years, the mean BMI was 22.46. Patients have taken PPI medication for 2 months, after medication, they performed HRM. Comparative analysis was performed with results of the difference in symptoms. Results : In 99 patients, 37 patients (37.4%) show not improvement of LPRD symptoms after PPI medication. Among them, 18 patients (48.6%) showed abnormal findings that were classified as Peristaltic dysfunction (38.9%), Diffuse esophageal spasm (11.1%), Relaxation impairment of LES (11.1%), Achalasia (5.6%), Hypotensive LES (11.1%), Relaxation impairment of UES (11.1%), Nutcracker esophagus (5.6%), Decreased resting pressure (5.6%). Other 62 patients (62.6%) show improvement of LPRD symptoms, 23 patients (37.1%) showed abnormal findings. Most common finding was Peristaltic dysfunction (43.4%) More prevalent abnormal findings of HRM were found in patients who revealed no response to PPI medication (48.6% vs. 37.1%), but it does not reach the statistical significance. Conclusion : Although statistical significances is not showed, the difference observed in the frequency of HRM abnormal finding between response and no response for PPI medication. It has been estimated that HRM may be used to determine differential diagnosis in patients with LPRD. Further studies in lager population containing normal controls will be needed to prove clinical usefulness.

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Signal-Averaged P Wave Analysis in Patients with Paroxysmal Atrial Fibrillation (발작성 심방세동 환자의 신호평균 P파 분석)

  • 김인영;이종연;이병채;이용희;이종민;김선일;김준수
    • Journal of Biomedical Engineering Research
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    • v.23 no.1
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    • pp.1-8
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    • 2002
  • Atrial fibrillation(AF). chronic or paroxysmal is the most frequent arrhythmia in human subjects Duration of P wave in signal-averaged electrocardiography(SAECG) reflects intra-atrial conduction time and therefore. could be used as an electrophysiological marker for atrial conduction chance at the earthy stave. So we apply the analysis method using SAECG to diagnose Paroxysmal atrial fibrillation(PAF) . Subjects Participated for the study consisted of two groups: a control group(n=34) of normal healthy volunteers and a group of AF Patients(n=38) with a documented history of PAF but no other history of cardiac disease. We evaluated the effect of several filtering and determination methods to find the starting and ending feints of the P wavy on its duration. To increase the measurement reliability of P wave duration. the automatic detection method was proposed. Also. to increase the detection rate for PAF risk, the decision threshold value was optimized using receiver operation characteristics(ROC) curve. Results showed that the highest statistical difference (p〈0.001) of the P wane duration between controls and subjects was obtained at the Processing condition, using absolute threshold vague(8.75 $\mu N$) , a least mean square(LMS) high pass filter and 30 Hz cutoff frequency. The most outstanding difference(sensitivity 88 % specificity 64.4 %) between controls and subjects was obtained at the decision threshold value of 112 ms.