• Title/Summary/Keyword: frequency response test

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Context Prediction Using Right and Wrong Patterns to Improve Sequential Matching Performance for More Accurate Dynamic Context-Aware Recommendation (보다 정확한 동적 상황인식 추천을 위해 정확 및 오류 패턴을 활용하여 순차적 매칭 성능이 개선된 상황 예측 방법)

  • Kwon, Oh-Byung
    • Asia pacific journal of information systems
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    • v.19 no.3
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    • pp.51-67
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    • 2009
  • Developing an agile recommender system for nomadic users has been regarded as a promising application in mobile and ubiquitous settings. To increase the quality of personalized recommendation in terms of accuracy and elapsed time, estimating future context of the user in a correct way is highly crucial. Traditionally, time series analysis and Makovian process have been adopted for such forecasting. However, these methods are not adequate in predicting context data, only because most of context data are represented as nominal scale. To resolve these limitations, the alignment-prediction algorithm has been suggested for context prediction, especially for future context from the low-level context. Recently, an ontological approach has been proposed for guided context prediction without context history. However, due to variety of context information, acquiring sufficient context prediction knowledge a priori is not easy in most of service domains. Hence, the purpose of this paper is to propose a novel context prediction methodology, which does not require a priori knowledge, and to increase accuracy and decrease elapsed time for service response. To do so, we have newly developed pattern-based context prediction approach. First of ail, a set of individual rules is derived from each context attribute using context history. Then a pattern consisted of results from reasoning individual rules, is developed for pattern learning. If at least one context property matches, say R, then regard the pattern as right. If the pattern is new, add right pattern, set the value of mismatched properties = 0, freq = 1 and w(R, 1). Otherwise, increase the frequency of the matched right pattern by 1 and then set w(R,freq). After finishing training, if the frequency is greater than a threshold value, then save the right pattern in knowledge base. On the other hand, if at least one context property matches, say W, then regard the pattern as wrong. If the pattern is new, modify the result into wrong answer, add right pattern, and set frequency to 1 and w(W, 1). Or, increase the matched wrong pattern's frequency by 1 and then set w(W, freq). After finishing training, if the frequency value is greater than a threshold level, then save the wrong pattern on the knowledge basis. Then, context prediction is performed with combinatorial rules as follows: first, identify current context. Second, find matched patterns from right patterns. If there is no pattern matched, then find a matching pattern from wrong patterns. If a matching pattern is not found, then choose one context property whose predictability is higher than that of any other properties. To show the feasibility of the methodology proposed in this paper, we collected actual context history from the travelers who had visited the largest amusement park in Korea. As a result, 400 context records were collected in 2009. Then we randomly selected 70% of the records as training data. The rest were selected as testing data. To examine the performance of the methodology, prediction accuracy and elapsed time were chosen as measures. We compared the performance with case-based reasoning and voting methods. Through a simulation test, we conclude that our methodology is clearly better than CBR and voting methods in terms of accuracy and elapsed time. This shows that the methodology is relatively valid and scalable. As a second round of the experiment, we compared a full model to a partial model. A full model indicates that right and wrong patterns are used for reasoning the future context. On the other hand, a partial model means that the reasoning is performed only with right patterns, which is generally adopted in the legacy alignment-prediction method. It turned out that a full model is better than a partial model in terms of the accuracy while partial model is better when considering elapsed time. As a last experiment, we took into our consideration potential privacy problems that might arise among the users. To mediate such concern, we excluded such context properties as date of tour and user profiles such as gender and age. The outcome shows that preserving privacy is endurable. Contributions of this paper are as follows: First, academically, we have improved sequential matching methods to predict accuracy and service time by considering individual rules of each context property and learning from wrong patterns. Second, the proposed method is found to be quite effective for privacy preserving applications, which are frequently required by B2C context-aware services; the privacy preserving system applying the proposed method successfully can also decrease elapsed time. Hence, the method is very practical in establishing privacy preserving context-aware services. Our future research issues taking into account some limitations in this paper can be summarized as follows. First, user acceptance or usability will be tested with actual users in order to prove the value of the prototype system. Second, we will apply the proposed method to more general application domains as this paper focused on tourism in amusement park.

A Descriptive Study of Oral Health Knowledge & Behaviors in Middle School Students (일부지역 중학생의 구강건강 지식 및 행동에 관한 조사연구)

  • Yoo, Jung-Sook;Kim, Jung-Hee;Han, Su-Jin;Sim, Sang-Hyo;Kim, Yoon-Shin
    • The Journal of Korean Society for School & Community Health Education
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    • v.9 no.1
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    • pp.85-97
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    • 2008
  • Objectives: This study was designed to understand the oral health knowledge & conduct of middle-school students, search for the learning objective and the educational method in line with the subjects and of utilizing as the basic data for an effective oral health-care program. Methods: The samples to achieve the purpose of this research are composed of 139 students in middle-school, OO county. Chungcheongbuk-do, the number of male students 64, and female students 75. Data were statistically analyzed by frequency analysis, $x^2$-test or Fisher's exact test by using SPSS WIN Ver. 12.0. Results: Among items on oral-health knowledge in middle-school students. the awareness ratio on a cause and preventive method for oral disease was surveyed to be lower than the awareness ratio on symptoms of oral disease. As a result of examining by comparing knowledge and behavior on the time of tooth brush. both awareness and behavior were the level of 50% or less than it. In particular, 46.2% perceived after lunch. but practice just accounted for 33.0%. The frequency of tooth brush a day was the largest in a case(47.5%) of doing twice a day. However. there was also the response (5.8%) with saying of brushing once or not brushing even once. Thus, the practice of tooth brush was surveyed to be very low even if being a minority of students. The frequency of taking a light meal was 68.8% in less than twice a day. However, even students of taking more than five times were surveyed to be 9.8%. Out of the whole-body health in over 50%-59.9%. the oral health was surveyed to be perceived to be very important. Compared to the awareness level on importance of a tooth, the ratio of visiting a dentistry was analyzed to be very low. Conclusions: The study results suggest that the school oral-health project was examined to have the necessity of being expanded and carried out even in middle-and-high schools, by which the specific oral-health promotion program including oral-health education in this period is developed.

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A Development of Framework for Selecting Labor Attendance Management System Considering Condition of Construction Site (건설 현장 특성을 고려한 출역관리시스템 선정 프레임워크 개발)

  • Kim, Seong-Ah;Chin, Sang-Yoon;Jang, Moon-Seok;Jung, Choong-Won;Choi, Cheol-Ho
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.4
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    • pp.60-69
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    • 2015
  • Labor attendance management has traditionally been carried out by writing a table for checking an attendance of labor, which requires a lot of time and effort. As electronic devices with additions such as barcodes, Quick Response codes, and Radio Frequency Identification(RFID) have been developed, however, automated labor attendance management systems have appeared. Recently, various types of labor recognition devices converged with biometrics (fingerprint, vein, face recognition, etc.) have been released. However, although these devices can be used to check attendance automatically, there is insufficient guidance when it comes to selecting the appropriate labor attendance management system for construction sites. Therefore, this study proposed a decision framework to determine which labor attendance management system would be suitable for a construction site and to select the labor recognition device. This study investigated different labor recognition devices, focusing on how they worked, and tested the performance of devices and their usability for construction labor attendance management. The test results showed that RFID is most suitable when verifying the attendance of many laborers over a short period of time. The devices for hand vein and fingerprint recognition did not function when there was a foreign material such as cement or paint on the laborer's hand, except for a deformed finger. Reflecting these test results, this study suggested a framework for selecting a labor attendance system and recognition device; this is expected to contribute to the development of more efficient labor management systems.

A Crash Prediction Model for Expressways Using Genetic Programming (유전자 프로그래밍을 이용한 고속도로 사고예측모형)

  • Kwak, Ho-Chan;Kim, Dong-Kyu;Kho, Seung-Young;Lee, Chungwon
    • Journal of Korean Society of Transportation
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    • v.32 no.4
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    • pp.369-379
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    • 2014
  • The Statistical regression model has been used to construct crash prediction models, despite its limitations in assuming data distribution and functional form. In response to the limitations associated with the statistical regression models, a few studies based on non-parametric methods such as neural networks have been proposed to develop crash prediction models. However, these models have a major limitation in that they work as black boxes, and therefore cannot be directly used to identify the relationships between crash frequency and crash factors. A genetic programming model can find a solution to a problem without any specified assumptions and remove the black box effect. Hence, this paper investigates the application of the genetic programming technique to develope the crash prediction model. The data collected from the Gyeongbu expressway during the past three years (2010-2012), were separated into straight and curve sections. The random forest technique was applied to select the important variables that affect crash occurrence. The genetic programming model was developed based on the variables that were selected by the random forest. To test the goodness of fit of the genetic programming model, the RMSE of each model was compared to that of the negative binomial regression model. The test results indicate that the goodness of fit of the genetic programming models is superior to that of the negative binomial models.

Output-Only System Identification and Model Updating for Performance Evaluation of Tall Buildings (초고층건물의 성능평가를 위한 응답의존 시스템판별 및 모델향상)

  • Cho, Soon-Ho
    • Journal of the Earthquake Engineering Society of Korea
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    • v.12 no.4
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    • pp.19-33
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    • 2008
  • Dynamic response measurements from natural excitation were carried out for 25- and 42-story buildings to evaluate their inherent properties, such as natural frequencies, mode shapes and damping ratios. Both are reinforced concrete buildings adopting a core wall, or with shear walls as the major lateral force resisting system, but frames are added in the plan or elevation. In particular, shear walls in a 25-story building are converted to frames from the 4th floor level downwards while maintaining a core wall throughout, resulting in a fairly complex structure. Due to this, along with similar stiffness characteristics in the principal directions, significantly coupled and closely spaced modes of motion are expected in this building, making identification rather difficult. By using various state-of-the-art system identification methods, the modal parameters are extracted, and the results are then compared. Three frequency-domain and four time-domain based operational modal identification methods are considered. Overall, all natural frequencies and damping ratios estimated from the different identification methods showed a greater consistency for both buildings, while mode shapes exhibited some degree of discrepancy, varying from method to method. On the other hand, in comparison with analysis results obtained using the initial finite element(FE) models, test results exhibited a significant difference of about doubled frequencies, at least for the three lower modes in both buildings. To improve the correlation between test and analysis, a few manual schemes of FE model updating based on plausible reasons have been applied, and acceptable results are obtained. The advantages and disadvantages of each identification method used are addressed, and some difficulties that might arise from the updating of FE models, including automatic procedures, for such large structures are carefully discussed.

Two Cases of Cerebral Cysticercosis Treated with Albendazole (Albendazole을 이용한 뇌낭미충증(腦囊尾蟲症) 치험(治驗) 2예)

  • Joo, Kyoung-Hwan;Rim, Han-Jong
    • Journal of agricultural medicine and community health
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    • v.16 no.2
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    • pp.165-171
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    • 1991
  • Two patients with confirmed cerebral cysticercosis were treated with Albendazole(Zentel$^{(R)}$) at a daily dose of 1.200mg t.i.d. for 14 consecutive days and evaluated for tolerance and therapeutic effects. First case was 29 year old male, who had experience of 4 times of grand mal seizures during 1 year period before administration in Korea University Hospital. His chief complaints were seizure and moderate degree headache. He also had 4 subcutaneous nodules on the thorax, right and left upper arms. Among them one nodule was biopsied and confirmed microscopically as Cysticercus cellulosae hominis. Computed tomography of the brain showed four round low density lesions in right postero-frontal area, sylvian area, intra-occipital area and left parietal area. Second case was 48 year old male, who also had experience of seizures at 3 years, 5 months and 3 months before administration. In this case, no subcutaneous nodules and no headaches were noted. Brain CT showed four round low density lesions in right postero-parietal area and temporo-parietal area, and left temporo-parietal and parietal area. Serum antibody against cystic fluid antigen was detected by ELISA in both cases. The efficacy of the treatment of cerebral cysticercosis was assessed by the frequency of convulsions after treatment for 22 months follow-up. by the disappearance of the densities in cystic lesions at brain CT for 6 months follow-up, and disappearance of subcutaneous nodules, headache and so on. As the results, all low density lesions in both cases were disappeared in films of brain CT, and 4 nodules in first case were also disappeared. No more seizure and complain of headache occurred during the last 22 months after treatment in both cases. Post-treatment complete blood count and liver function test revealed no remarkable change compared to pre-treatment test. In the nations of Latin America, the physicians do not initially recommended the simultaneous administrations of steroids, reserving them only for patients whom the adverse reactions such as severe headache and/or seizures are occurred. According to them, in most patients these symptoms are controlled with aspirin and symptomatic drugs. But our experience using praziquantel is different, and most cerebral cysticercosis patients who takes PZQ had complaint of severe headache and sometimes seizure. So we simultaneously used dexamethasone as 6mg q.i.d. for 14 consecutive days and 6 days tapering thereafter in both cases for prevention of reactions produced by the host in response to the deaths of the parasites. As the conclusion, albendazole is effective in patients who presented cerebral cysticercosis and albendazole may help in the control of cysticercosis.

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Experimental Verification of Implantable Middle Ear System using the Differential Electromagnetic Type Transducer (차동 전자 트랜스듀서를 이용한 이식형 인공중이 시스템의 실험적 검증)

  • 송병섭;이기찬;원철호;박세광;이상흔;조진호
    • Journal of Biomedical Engineering Research
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    • v.23 no.3
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    • pp.217-225
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    • 2002
  • The implantable middle ear(IME) system, which has good sound quality. superior sound intelligibility and wide frequency characteristics. can resolve the sound distortion and ringing effect by sound feedback at high gain operation those are the major problems of conventional hearing aid. In this paper, we have manufactured the IME system using differential electromagnetic transducer(DET) and verified the performance of the system by carrying out vibration and animal implanting experiment. The DET was manufactured using micro-machining technology and vibration experiment of the transducer was performed to inspect whether the transducer could vibrate in accordance with the applied sound signal or not. And the result of the loaded experiment using temporal bone sampled from cadaver showed that the transducer can drive the middle ear bone and transmit the signal to inner ear After the internal unit of IME system was implanted in a dog. the auditory brainstem response (ABR) test was carried out. The result of the test indicated the Proper behavior of the IME system in the living body From the results of the experiments, it is verified that the manufactured system ewll work well when it is applied to human and a basis of clinical experiment of IME system to real human hearing impaired was be arranged.

Effect of Participation in Regular Leisure Sports on Satisfaction with Family Relationship in Adolescents (청소년의 규칙적인 여가스포츠 참여가 가족관계 만족도에 미치는 영향)

  • Cho, Hyungsun;Hwang, Sunhwan;Bang, Shinwoong
    • The Journal of the Korea Contents Association
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    • v.15 no.11
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    • pp.591-602
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    • 2015
  • The purpose of this study was to examine the effect of participation in regular leisure sports on satisfaction with family relationship in adolescents. To achieve this purpose, 650 students of elementary and middle schools in Seoul and Gyeonggi area were selected and surveyed using the purposive sampling method. 611 survey samples were used in final analysis and 39 survey samples were excluded because of untrustworthy response. Statistical program AMOS 18.0 was used to conduct the confirmatory factor analysis and goodness of fit test, and SPSS 21.0 Window program was used to conduct analysis of frequency, t-test, and ANOVA. Through the analysis, the main findings were as follows; First, it was found that the adolescents participating in regular leisure sports has significant difference in satisfaction with family relationships compared to non-participation group. Second, satisfaction with family relationship of parental participation group in regular leisure sport was high the most followed by lonely participation group and non-participation group. Finally, authors described the implications and future studies.

Development of a Korean Sexual Satisfaction Scale (한국 성인의 성만족 측정도구 개발)

  • Lee Byung-Sook;Koh Hyo-Jung;Kim Myung-Ae;Im Shin-Hwa
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.9 no.2
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    • pp.190-200
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    • 2002
  • Purpose; The purpose of this study was to develop an instrument to measure sexual satisfaction in Korean adults. Method: Development of items for the instrument was done by a collecting, reorganizing, reducing and selecting process based on the literature. A total of 19 items were selected in this process. For evaluation of the appropriateness of the 19 items, questionnaires were given to an expert group consisting of 18 professionals (7 men and 11 women). Eighteen items having a response of 70% in 'very good' item or 'good' item were included as items for the instrument. With these 18 items, a 5 point Likert scale was developed, and reliability and validity tests of the scale were done. The subjects for the test were 1,127 Korean adults living in 11 areas in Korea, Data were collected from Dec. 1, 2000 to Feb. 28, 2001 and analyzed with SPSS/PC+ 10.0 program. Item analysis and factor analysis were used to assess the reliability and validity of the scale. Chronbach alpha and corrected item-total correlation were obtained to verify internal consistency, and principal component analysis with the varimax rotation was used to identify structure validity of the developed tool. Result: Reliability of the scale was .9503 and corrected item-total correlations of the items were distributed from .5208 to 7899. As a result of the factor analysis, the items were categorized into three factors. The cumulative variance of the three factors was 67.1%, and all of the variances of the factors were above 5%. Because factor 1 (8 items) indicated a special feeling of psychological satisfaction with sexual activity, it was named 'psychological factor'. Factor 2 (8 items) indicated a feeling of satisfaction in the interaction with sexual partner through communication and variation, therefore it was named 'interactional factor'. Factor 3 (2 items) was about the frequency and duration of sexual intercourse and indicated physical dimensions of satisfaction, so it was named 'physical factor'. The average score for sexual satisfaction of the 1,127 subjects was 65.32 (${\pm}12.71$), and histogram of the score showed a normal distribution with skewness - .425. Conclusion: Finally, a Korean Sexual Satisfaction Scale(KSSS) was accepted as a 5 point Likert scale with 18 items after the statistical test for reliability and validity. In conclusion, KSSS is a useful instrument which is valid and reliable can be used to understand the sexuality of Korean adults.

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Clinical Features of Chronic Obstructive Pulmonary Disease with High Fractional Exhaled Nitric Oxide

  • Ahn, Seong;Kim, Tae-Ok;Chang, Jinsun;Shin, Hong-Joon;Kwon, Yong-Soo;Lim, Sung-Chul;Kim, Yu-Il
    • Tuberculosis and Respiratory Diseases
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    • v.83 no.3
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    • pp.234-241
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    • 2020
  • Background: The fractional exhaled nitric oxide (FENO) test is useful in asthma patients. However, a few studies on its usefulness in chronic obstructive pulmonary disease (COPD) patients have been reported. We analyzed the FENO level distribution and clinical characteristics according to the FENO level in COPD patients. Methods: From December 2014 to June 2019, COPD patients who underwent pulmonary function and FENO tests at Chonnam National University Hospital were retrospectively evaluated for FENO, comorbidities, asthma history, blood eosinophil, and pulmonary function test. The high FENO group was defined as those with FENO level>25 parts per billion (ppb). Results: A total of 849 COPD patients (mean age, 70.3±9.4 years) were included. The mean forced expiratory volume at 1 second was 66.5±21.7% and the mean FENO level was 24.3±20.5 ppb. Patients with FENO ≤25 ppb were 572 (67.4%) and those with FENO >25 ppb were 277 (32.6%). Blood eosinophil percentage was significantly higher (4.2±4.8 vs. 2.7±2.5, p<0.001) in patients with the high FENO group than the low FENO group. The high FENO group revealed a significantly higher frequency of patients with blood eosinophil percentage >3% (46.9% vs. 34.8%, p=0.001) and asthma history (25.6% vs. 8.6%, p<0.001) than the lower FENO group. Asthma history, blood eosinophil percentage >3%, and positive bronchodilator response (BDR) were independent risk factors for the high FENO level (adjusted odds ratio [aOR], 3.85; p<0.001; aOR, 1.46; p=0.017; and aOR, 1.57, p=0.034, respectively) in the multivariable analysis. Conclusion: The FENO level distribution varied in COPD patients and the mean FENO value was slightly elevated. Asthma history, eosinophil percent, and positive BDR were independent risk factors for the high FENO level.