• 제목/요약/키워드: Difference-In-Difference

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보건용 마스크의 요구사항 및 만족도 (Requirements and satisfaction with medical masks)

  • 박영희
    • 복식문화연구
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    • 제31권1호
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    • pp.1-17
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    • 2023
  • This study analyzed requirements for medical masks and difference in satisfaction based on demographic characteristics and side effects experience caused by wearing medical masks. Three factors related to requirements for medical masks were identified: wearing comfort and usability, blocking function for harmfulness, and design. As a result of the difference analysis for requirements of medical masks based on demographic characteristics, all three factors showed a significant difference in gender and occupation. Design did in age and monthly income. As a result of the presence or absence of breathing difficulties experience, design factor was significant. As a result of the presence or absence of skin trouble experience, wearing comfort and usability showed a significant difference. As a result of the difference in satisfaction with medical masks based on demographic characteristics and side effect experience caused by wearing medical masks, breathing, ear string tightness, blocking harmful substances, price, and over all wearing comfort showed a significant difference by gender, marital status, age, occupation, and monthly income, and the presence of absence of breathing difficulty experience and skin trouble experience, respectively. As a result of the interaction effect analysis between demographic characteristics and side effects experience caused by wearing medical masks, it showed a significant interaction effect between gender and monthly income, between marital status and monthly income, between monthly income and breathing difficulties experience, and between monthly income and skin trouble experience.

Temperature distribution analysis of steel box-girder based on long-term monitoring data

  • Wang, Hao;Zhu, Qingxin;Zou, Zhongqin;Xing, Chenxi;Feng, Dongming;Tao, Tianyou
    • Smart Structures and Systems
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    • 제25권5호
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    • pp.593-604
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    • 2020
  • Temperature may have more significant influences on structural responses than operational loads or structural damage. Therefore, a comprehensive understanding of temperature distributions has great significance for proper design and maintenance of bridges. In this study, the temperature distribution of the steel box girder is systematically investigated based on the structural health monitoring system (SHMS) of the Sutong Cable-stayed Bridge. Specifically, the characteristics of the temperature and temperature difference between different measurement points are studied based on field temperature measurements. Accordingly, the probability density distributions of the temperature and temperature difference are calculated statistically, which are further described by the general formulas. The results indicate that: (1) the temperature and temperature difference exhibit distinct seasonal characteristics and strong periodicity, and the temperature and temperature difference among different measurement points are strongly correlated, respectively; (2) the probability density of the temperature difference distribution presents strong non-Gaussian characteristics; (3) the probability density function of temperature can be described by the weighted sum of four Normal distributions. Meanwhile, the temperature difference can be described by the weighted sum of Weibull distribution and Normal distribution.

콘크리트 바닥판의 아스팔트 두께에 따른 강박스거더교의 상하 온도차 (Vertical Temperature Difference of Steel Box Girder Bridge Considering Asphalt Thickness of Concrete Deck)

  • 이성행
    • 한국산학기술학회논문지
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    • 제20권3호
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    • pp.602-608
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    • 2019
  • 본 연구에서는 강박스거더교 바닥판의 아스팔트 두께에 따른 단면 상하 온도차를 산정하고, 이에 따른 설계기준의 자료를 제공하고자 하였다. 아스팔트 두께 0mm, 50mm, 100m, 150mm의 4개 강박스거더 모형시험체를 제작하였다. 각 모형에 17~23개의 온도 센서를 상부 콘크리트와 강박스거더에 부착하였다. 이 센서 중 Euro code와 온도차를 비교 할 수 있는 6개의 온도 게이지를 선정하였다. 각 모형의 기준 대기온도에서 최대 온도와 최저 온도를 계산하고, 이를 바탕으로 온도차(경사)를 산정하여, 4개 각 모형에서 온도차 모델을 제시하였다. 0mm ~ 100mm 온도차 모델은 슬래브 최상단에서 Euro code의 온도차와 비교할 때 -0.9~-1.5도 더 낮은 온도차를 보였다. 전체적으로 측정된 온도차는 Euro code와 비교하여 5.45%~8.33%정도의 오차가 있음을 확인하였다. 산정된 온도와 평균온도의 차를 표준오차의 배수로 산정한 표준오차 계수는 최상단과 최하 단에서 평균 2.50 ~ 2.51배의 값으로 일정한 범위에서 산정되었다. 제시된 온도차 모델은 국내 교량 온도설계 온도차 기준 산정 시 기본 자료로 활용될 수 있을 것으로 판단된다.

근광장 측정에서 방사선 사진술의 정확도 (The Accuracy of the Radiographic Method in Root Canal Length Measurement)

  • 조은영;박창서
    • 치과방사선
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    • 제28권2호
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    • pp.471-489
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    • 1998
  • For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora/sup (R)/, an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora/sup (R)/ system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora/sup (R)/ system and standard periapical radiograph was 0.002 mm and the standard deviation was 0.341 mm which showed no statistically significant difference between the two systems(p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mm and the standard deviation was 0.323 mm which showed no statistically significant difference between the two systems(p>0.05). 2. In Digora/sup (R)/ system, the average difference between the bisecting angle and paralleling technique was -0.336 mm and the standard deviation was 0.472 mm which showed a statistically significant difference between the two techniques(p<0.05). Also, in the standard periapical radiographs, the average difference between the bisecting angle and paralleling technique was 0.328 mm and the standard deviation was 0.517 mm which showed a statistically significant difference between these two techniques(p<0.05). 3. In Digora/sup (R)/ system and the standard periapical radiographs. there was a statistically significant difference between the measurement using the bisecting angle technique and the actual length(p<0.05), But there was no statistically significant difference between the measurement using the paralleling technique and the actuallength(p>0.05). In conclusion. the determination of the root canal length by using the Digora/sup (R)/ system can give us as good an image as the standard periapical radiograph and using the paralleling technique instead of the bisecting angle technique can give a measurement closer to the actual canal length. thereby contributing to a successful result. Also. considering the advantages of the digital imaging processor such as decreasing the amount of exposure to the patient. immediate use of the image. magnification of image size. control of the contrast and brightness and the ability of storing the image can give us good reason to replace the standard periapical radiographs.

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Validity of a Portable APDM Inertial Sensor System for Stride Time and Stride Length during Treadmill Walking

  • Tack, Gye Rae;Choi, Jin Seung
    • 한국운동역학회지
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    • 제27권1호
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    • pp.53-58
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    • 2017
  • Objective: The purpose of this study was to compare the accuracy of stride time and stride length provided by a commercial APDM inertial sensor system (APDM) with the results of three dimensional motion capture system (3D motion) during treadmill walking. Method: Five healthy men participated in this experiment. All subjects walked on the treadmill for 3 minutes at their preferred walking speed. The 3D motion and the APDM were simultaneously used for extracting gait variables such as stride time and stride length. Mean difference and root mean squared (RMS) difference were used to compare the measured gait variables from the two measurement devices. The regression equation derived from the range of motion of the lower limb was also applied to correct the error of stride length. Results: The stride time extracted from the APDM was almost the same as that from the 3D motion (the mean difference and RMS difference were less than 0.0001 sec and 0.0085 sec, respectively). For stride length, mean difference and RMS difference were less than 0.1141 m and 0.1254 m, respectively. However, after correction of the stride length error using the derived regression equation, the mean difference and the RMS difference decreased to 0.0134 m and 0.0556 m or less, respectively. Conclusion: In this study, we confirmed the possibility of using the temporal variables provided from the APDM during treadmill walking. By applying the regression equation derived only from the range of motion provided by the APDM, the error of the spatial variable could be reduced. Although further studies are needed with additional subjects and various walking speeds, these results may provide the basic data necessary for using APDM in treadmill walking.

어레이 압저항 센서를 활용한 체질맥 임상연구 (Clinical Study on the Sasang Constitutional Pulse Using Array Piezoresistive Sensor)

  • 이시우;주종천;김경요;김종열
    • 사상체질의학회지
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    • 제18권1호
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    • pp.118-131
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    • 2006
  • 1. Objective Pulse diagnosis is generally applied to Traditional Oriental Medicine but not to Sasang Constitution diagnosis. Recently new pulse analyzer using array piezoresistive sensor and multi-channel robot arm developed. It reflects Oriental Medical Doctors' diagnostic processes, and its reproducibility test was done at Korea Institute of Oriental Medicine. We performed this study to set parameters diagnosing Sasang Constitution. 2. Methods One hundred thirty three subjects participated in this study. They are healty and approved this study. Before being tested with pulse analyzer, they had interview with Sasang Constitution Specialist to diagnose their Sasang Constitution. We established some useful parameters from parameters of pulse analyzer according to the Original Texts of Oriental Medicine and clinical experiences to analyze with clinical data of this study. 3. Results (I) There is a significant difference in pre-dicrotic notch time among all parameters of pulse analyzer in Sasang Constitution groups(P=0.047). (2) There is a significant difference in maximum pulse pressure in 33 to 48 year Sasang Constitution groups(P=0.010). (3) There is a significant difference in frequency width in 17 to 32 year Sasang Constitution groups(P=0.002). (4) There is a significant difference in CFS value in groups which OMD diagnoses; Floating & Sinking pulse(P=0.020). (5) There is a significant difference in pulse rate in groups which OMD diagnoses; Rapid & Slow pulse(P=0.000). (6) There is a significant difference in maximum pulse pressure in groups which OMD diagnoses; Deficient & Solid pulse(P=0.000). 4. Conclusions Analyzing parameters in each Sasang Constitution group, we found it shows significant difference in maximum pulse pressure and corresponding tendency in coefficient of floating & sinking pulse with theories of Sasang Consti-tutional Medicine. As we accumulate more clinical data, we will establish algorithm to diagnose Sasang Constitution using a pulse analyzer.

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Effects of White Noises on Gait Ability of Hemiplegic Patients during Circuit Balance Training

  • Jang, Na-Young;Kim, Gi-Do;Kim, Bo-Kyoung;Kim, Eun-Hee;Koo, Ja-Pung;Shin, Hee-Joon;Choi, Seok-Joo;Choi, Wan-Suk
    • 국제물리치료학회지
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    • 제3권1호
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    • pp.370-377
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    • 2012
  • This study examines the effects of different environments on the application of hemiplegia patients circuit balance training. Group 1 performed circuit balance training without any auditory intervention Group 2 performed training in noiseless environments and Group 3 performed training in white noise environments. First, among lower extremity muscular strength evaluation items, maximum activity time(MAT) was not significantly different(p>.05). Maximum muscle strength(MMS) increased significantly in Group 3(p<.01), there was no significant difference in MMS among the groups. Average muscle strength(AMS) indexes also significantly increased in Group 3(p<.01), there was no significant difference in AMS among the groups. Second, among balancing ability evaluation items, Berg's balance scale(BBS) scores significantly increased in all groups(p<.05), BBS scores were significantly difference among the groups. Based on the results, Group 1, 2 and Group 1, 3 showed significant increases (p<.05). Functional reach test(FRT) values significantly increased in Group 2, 3(p<.05), and there was no significant difference in FRT values among the groups. Timed up and go(TUG) test values significantly decreased in Group 2, 3(p<.05), and there was no significant difference in TUG test values among the groups. Third, among walking speed evaluation items, the time required to walk 10m significantly decreased in all groups(p<.05), and there was no significant difference in the values among the groups. Average walking speeds showed significant increases in Group 1, 3(p<.05), and there was no significant difference in the values among the groups. Based on the results of this study, noise environments should be improved by either considering auditory interventions and noiseless environments, or by ensuring that white noise environments facilitate the enhancement of balancing ability.

제 3대구치와 인접한 제 2대구치의 치주상태에 대한 고찰 (A study on the periodontal status of second molar adjacent third molar)

  • 이해두;홍기석;정진형;임성빈
    • Journal of Periodontal and Implant Science
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    • 제36권2호
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    • pp.489-502
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    • 2006
  • The purpose of this study was to determine the relationship between the third molar and periodontal status of the adjacent second molar. Fifty patients who had four maxillary and mandibular second molars were consecutively selected for the study subjects. The subjects provided a total of 200 molars, i. e., 100 maxillary and 100 mandibular molars, and classified the groups as follows; third molars that are normally erupted are control group, that are impacted are test 1 group, that are simply extracted are test 2 group, that are surgically extracted are test 3 group. Probing depth, plaque index, gingival index and mobility were measured. The results were as follows. 1. In mesial probing depth, there was no significantly difference. In distal probing depth, there was a significantly difference between control group and test 1 & 3 group in maxilla and between control & test 2 group and test 1& 3 group in mandible(p<0.05). 2. In buccal probing depth, there was a significantly difference between test 2 group and test 3 group in mandible. In lingual probing depth, there was a significantly difference between control group and test 1 & 3 group in mandible(p<0.05). 3. In plaque index, there was a significantly difference between test 1 group and test 2 group in maxilla, between test 1 group and control & test 2 group in mandible(p<0.05). 4. In gingival index, there was a significantly difference between control group and test 1 & 3 group in mandible. In mobility, there was no significantly difference(p<0.05). As a result of this study, the second molars adjacent to the third molars that are impacted or surgically extracted had poor prognosis, so impacted third molars should be extracted in early time and the second molars are actively treated for periodontal health.

무용기반 저강도 복합운동요법이 당뇨노인의 생리적 지표에 미치는 효과 (Physiological Index of the Elderly with Diabetes According to Dance Based Low Intensity Combined Kinesitherapy)

  • 김수진
    • 한국콘텐츠학회논문지
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    • 제18권5호
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    • pp.683-694
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    • 2018
  • 본 연구는 제2형 당뇨병에 있어서 저강도의 복합적 운동요법을 시행하는 것이 효과적이라는 점과 무용-동작활동이 갖는 방법론적 측면의 유용성에 관한 이론적 근거 하에, 사전 동질성 검증을 거친 노인 당뇨환자에게 12주간 무용-동작활동과 저강도 복합운동을 처방한 실험군(병행군)과 저강도 복합운동만을 처방한 대조군(운동군)의 공복혈당 및 혈중지질의 사후검사 점수의 차이를 독립표본 t-test로 분석하였다. 연구의 주요 결과를 정리하면 다음과 같다. 첫째, 공복시 혈당은 집단별 사전-사후 차이에서 실험군의 차이가 대조군보다 큰 것으로 나타났다. 둘째, 총 콜레스테롤은 집단별 사전-사후 차이에서 실험군이 통계적으로 유의미한 차이가 있는 것으로 나타났다. 셋째, 중성지방은 집단별 사전-사후 차이에서 실험군과 대조군 모두 통계적으로 유의미한 차이가 없는 것으로 나타났다. 넷째, 고밀도 지단백 콜레스테롤은 집단별 사전-사후 차이에서 실험군과 대조군 모두 통계적으로 유의미한 차이가 없는 것으로 나타났다. 다섯째, 저밀도지단백콜레스테롤은 집단별 사전-사후 차이에서 실험군이 통계적으로 유의미한 차이가 있는 것으로 나타났다. 결국 본 연구는 기존에 다루지 못한 제 2형 당뇨노인에 있어서 무용-동작활동과 저강도 복합운동의 병행 효과를 생리적 지표를 이용하여 정량적으로 입증하였다는데 의의가 있다.

The Design Harmony in the Necktie with Dot Pattern

  • Jung, Su-Jin;Choi, Su-Koung
    • 패션비즈니스
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    • 제13권6호
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    • pp.31-44
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    • 2009
  • This study aims at clarifying the influence that color, tone, dot size, the combination of area ratios exercise on the harmony in dot necktie, and revealing the harmony differentiation according to the cues of various factors for pattern design. The conclusion is drawn as below, in the result that the cues which can exercise influence on the harmony of dot necktie, was analyzed by 54 stimuli. In the result of analysis of variance in order to clarify the influence which color, tone, dot size, and color area ratio exercise on dot necktie harmony, color and dot size operate appeared to be independent cues which exercise significant influence with main effect. In the result of the harmony difference analysis on color, tone, dot size, and color area ratio combination by multiple comparison, the cyan color in vivid tone was estimated to be most inharmonious in the analysis by color and tone. Viewing the harmony difference according to color and dot size, the dot size of 0.5cm in cyan was perceived to be most harmonious. Viewing the harmony difference according to color and color area ratio combination, both magenta and cyan were estimated to be positive, regardless of area ratio combination, and particularly, the case that the background was in cyan and the dots were in grey was perceived more harmonious compared to the contrary case. Viewing the harmony difference according to tone and dot sizes, the case when the dot sizes were 0.5cm, was perceived to be most positive, regardless of tone. Viewing the harmony difference according to color area ratio combination and tone, the case that the chromatic colors, cyan, magenta, and yellow was used as background, was estimated to be more harmonious, compared to the case that the achromatic color, grey was used as background. Viewing the harmony difference according to dot size and color area ratio combination, in case that the dots were in chromatic color and the background was in grey, the harmony showed difference by dot size, and the case of the dot size of 0.5cm was estimated to be most harmonious.