• Title/Summary/Keyword: Long Term Measurement

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A Study on the Performance Indicators of SME's International Marketing Program (중소기업 수출역량강화사업의 성과지표에 관한 연구)

  • Han, Min-Chung;Ahn, Byung-Soo
    • International Commerce and Information Review
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    • v.16 no.3
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    • pp.141-158
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    • 2014
  • This research is intended to improve the performance of "small and medium companies international marketing program" by screening the performance indicators of the program. The program aims to prepare SMEs to penetrate foreign market and become global companies eventually. This research analyzed the current SMEs international marketing programs based on Logic Model to find the current performance measurement lacks in qualitative indicators and process evaluation with focusing on quantitative indicators and short term result evaluation. Therefore, the measurement indicators should be balanced between process and results including mid-term and long term results.

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Statistical Analysis on the Temperature Dependence and Long-Term Change of Relative Humidity Sensors (상대습도계의 온도 의존성과 경년변화의 통계적 분석)

  • Kim, Jong Chul;Choi, Byung Il;Woo, Sangbong;Yang, Inseok
    • Journal of Sensor Science and Technology
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    • v.21 no.6
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    • pp.420-424
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    • 2012
  • We have investigated temperature dependence and long-term change of humidity measurement from 32 relative humidity sensors. The readings of the humidity sensors depended not only the reference humidity, but also temperature of the chamber. Approximately, the temperature dependence of the humidity sensor in average was 0.05 %R.H./$^{\circ}C$ in the temperature range from $5^{\circ}C$ to $55^{\circ}C$. For humidity sensors that have an internal temperature compensation circuit, the resulting temperature dependence was weaker by 20%. It should be also noted that for the humidity sensors used in this work underwent ${\pm}3$ %R.H. change per year for level of confidence of 95%. The users of relative humidity sensors may refer this value as a minimum change when they set the calibration interval of the humidity sensors.

The Reliability and Validity of Korean Version of the Wheelchair User's Shoulder Pain Index in Wheelchair Users (휠체어 사용자를 위한 한국어판 WUSPI의 신뢰도와 타당도)

  • Park, Ji-Yeon;Cho, Sang-Hyun
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.4
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    • pp.573-582
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    • 2013
  • PURPOSE: The purpose of this study was to establish the reliability and validity of the Wheelchair User's Shoulder Pain Index (WUSPI), which was translated into Korean for long-term wheelchair users. This index measured 15 functional activities, including transfer, self-care, wheelchair mobility and general activities. METHODS: To assess test-retest reliability, 23 long-term wheelchair users completed this self-administered index twice within the same day. Reliability was determined by the intraclass correlation coefficient (ICC), and Cronbach's alpha was used to measure internal consistency. To examine concurrent validity, 21 long-term wheelchair users completed the questionnaire, and we examined the correlation between the index score and the shoulder range of motion measurements. RESULT: The results showed that the intraclass correlation for test-retest reliability of the total index score ranging from .88 to .99 was good to excellent. Additionally, Cronbach's alpha was .96. The internal consistency indicated excellent. Concurrent validity showed negative correlations of total index score to range of motion measurements of shoulder flexion (rho=-.58), extension (rho=-.09), abduction (rho=-.59), external rotation (rho=-.07) and internal rotation (rho=-.3), suggesting a relationship of total index score to loss of shoulder range of motion. CONCLUSION: The Korean WUSPI shows not only high reliability and internal consistency, but also concurrent validity with loss of shoulder flexion and abduction.

Effect of long-term thermal aging on the microstructural and mechanical characteristics of nickel-based alloy weldment (니켈계 합금 용접부의 미세조직 및 기계적 특성에 대한 장기 열적 시효의 영향)

  • Yoo, Seung Chang;Ham, Junhyuk;Kim, Ji Hyun
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.12 no.1
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    • pp.41-48
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    • 2016
  • To investigate the effect of long-term thermal aging on the microstructural and mechanical characteristics of weldment made of nickel base alloy and its weld metal, an accelerated heat treatment was applied to simulate the process of long-term thermal aging in the operating condition of nuclear power plant. A representative nickel-based weldment with Alloy 600 and Alloy 182 was fabricated and heat-treated at $400^{\circ}C$ for 1,713 h and 3,427 h to simulate the thermal aging for the period equivalent to 15 and 30 years in operating pressurized water reactors, respectively. The microstructural and mechanical characteristics were analyzed by using optical microscopy, scanning electron microscopy and Vickers microhardness measurement. Changes were observed in precipitation behavior and microhardness of each specimen, and these changes were mainly attributed to the change in precipitated morphology and residual stress across the weld during the thermal aging process.

Long-Term Monitoring and Analysis of a Curved Concrete Box-Girder Bridge

  • Lee, Sung-Chil;Feng, Maria Q.;Hong, Seok-Hee;Chung, Young-Soo
    • International Journal of Concrete Structures and Materials
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    • v.2 no.2
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    • pp.91-98
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    • 2008
  • Curved bridges are important components of a highway transportation network for connecting local roads and highways, but very few data have been collected in terms of their field performance. This paper presents two-years monitoring and system identification results of a curved concrete box-girder bridge, the West St. On-Ramp, under ambient traffic excitations. The authors permanently installed accelerometers on the bridge from the beginning of the bridge life. From the ambient vibration data sets collected over the two years, the element stiffness correction factors for the columns, the girder, and boundary springs were identified using the back-propagation neural network. The results showed that the element stiffness values were nearly 10% different from the initial design values. It was also observed that the traffic conditions heavily influence the dynamic characteristics of this curved bridge. Furthermore, a probability distribution model of the element stiffness was established for long-term monitoring and analysis of the bridge stiffness change.

Long-term stabilization of optical feedback of a resonant external cavity coupled semiconductor laser (공진형 외부 캐비티 부착 반도체 레이저의 광피드백 장기 안정화)

  • 신철호
    • Korean Journal of Optics and Photonics
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    • v.9 no.2
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    • pp.96-99
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    • 1998
  • In this study, a novel long term stabilization method of optical feedback for the resonant cavity coupled semiconductor lasers is proposed, and its utility was shown experimentally. The proposed method is realized by using the pahse discriminator of optical feedback with high gain. The phase discriminating signal was obtained by the polarization spectroscopic technique using reflection light from the external reflector, which is a confocal Fabry-Perot cavity. Experimental result shows that stable control state can be maintained up to 20 hours. The period can be increased by reducing size of the system and/or fixing position stably of optical parts used, which were arranged on an optical table by using magnetic bases in this experiment. The proposed long-term stabilization method of optical feedack of a resonant external cavity coupled semiconductor laser is very useful for the field of high sensitivity measurement, and for the use in the laboratory level in particular.

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Long-Term Effects of the Self-Help Program for Arthritis Patients (관절염 환자를 위한 자조관리과정의 장기효과 연구)

  • Lee, Kyung-Sook;Lee, In-Ok;Jang, In-Ok;Lee, Eun-Ok;Suh, Moon-Ja
    • Journal of muscle and joint health
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    • v.10 no.1
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    • pp.32-43
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    • 2003
  • The purpose of this study was to identify the long-term effects of the self-help program for arthritis patients. The subjects were 126 patients who have participated in the 6-week self-help program from 1997 to 2000, agreed to participate in this study by telephone interview and responded the mailed questionnaires. The measurement tools of this study were all self-reported questionnaires such as Numerical Pain Rating Scale, the number of pain sites, Korean Health Assessment Questionnaire, Numerical Fatigue Rating Scale, CES-D depression scale, Self-efficacy scale, Social support scale. The repeated measure ANOVA revealed the significant differences among the pre post follow-up pain and fatigue. Whileas there were no significant differences the pre post follow-up pain site and physical functioning. And there were also no significant differences the pain, pain site, fatigue and physical functioning among three groups according to the duration of follow-up. These results suggested that the follow-up program after the self-help program was completed would be helpful for the physical wellbeing of arthritis patients.

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Damping Ratio Evaluation Using Long-Term Ambient Vibration (장기간 상시계측을 통한 감쇠율 평가)

  • Kim, Yong Chul;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.18 no.1
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    • pp.77-84
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    • 2018
  • The identification of damping ratios in buildings is a well-known problem and appears to be of important and crucial interest in the safety and serviceability design. When compared to an estimation of the stiffness, i.e. natural frequency, and mass, the damping ratio is the most difficult quantity to determine. Many previous studies have examined the characteristics of damping ratios from ambient vibration, but the measurement time is roughly within 2 hours. In this paper, characteristics of damping ratios and natural frequencies of 4 story RC building were investigated using long-term ambient vibration. Free vibrations were obtained using random decrement technique, and damping ratios were evaluated by the envelop function, continuous wavelet transform, and logarithmic decrement. It was found that although the natural frequencies show little variations with time, the damping ratios show some variations with time and the largest variations found in the damping ratios obtained from the continuous wavelet transform. The damping ratios from the envelop function showed the smallest mean and standard deviation. And the probability distribution of damping ratios seems to follow the logarithmic normal distribution.

A Study on the Development of Long Term Exposure $NO_2$ Sampler (장기 노출 $NO_2$ 간이 샘플러 개발에 관한 연구)

  • 이동인;김윤선
    • Journal of the Korean Society of Safety
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    • v.10 no.2
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    • pp.105-112
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    • 1995
  • The concentrations of $NO_2$ were measured to estimate a new developed long term exposure $NO_2$ sampler at Pusan City considering the meteorological factors from May to July, in 1994. The monthly mean concentration of $NO_2$ was 15.9 PPb and 36.2 ${\mu}\ell$/day $NO_2$ and their high values were shown in the downtown of Pusan City which show potential pollution due to the increase of traffic activities and micrometeorological factors In and around the City. As a result of statistical correlation between $NO_2$ concentration by new sampling method and $NO_2$ concentration by the handy air sampler and chemiluminescent nitrogen oxides analyzer, 1994, correlation coefficients were high(r=0.93) and showed more than 0.88 value in the high concentration data set, which was arbitrarily divided into 30${\mu}\ell$ $NO_2$ concentration in an attempt to further investigate these relationships. Therefore, use of new developed long term exposure $NO_2$ sampler is good for $NO_2$ measurement and valuable for estimation of air quality in the urban and Industrial area.

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A Study on the Long-term Absorption Rate of Organic Insulation Materials (유기질 단열재 장기 흡수율에 관한 연구)

  • Kim, Hae-na;Park, Jun-Seo;Shin, Joung-Hyeon;Hong, Sang-Hun;Jung, Ui-In;Kim, Bong-Joo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.195-196
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    • 2022
  • Insulation material absorption rate is closely related to thermal conductivity. In Korea, there is no study on the change of insulation material in a long-term continuous exposure environment. In this study, basic data on the long-term durability of insulation materials were obtained by measuring the absorption rate of insulation materials over time. For the purpose of providing, as a result of the measurement, PIR class2 No.2 and PIR noncombustible show similar absorption rate trends, which is thought to be due to the fact that both are made of rigid urethane foam, and flame retardant EPS has the highest absorption rate except for PF. This is thought to be because there is a space for absorption between the beads and the beads. In the case of XPS, it is thought that the reason for showing the lowest absorption rate is that because it is produced by extrusion, it has a high density and thus has less space for moisture to penetrate.

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