• Title/Summary/Keyword: Difference equation

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Effect of Patient's Positioning on the Grade of Tendinosis and Visible Range of Infraspinatus Tendon on Ultrasound (초음파 영상에서 극하근 힘줄병의 단계와 관찰가능 범위에 환자의 자세가 미치는 영향)

  • Jee Won Chai;Joo-ho Lee;Dong Hyun Kim;Jina Park;So-Hee Oh;Su-Mi Shin
    • Journal of the Korean Society of Radiology
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    • v.84 no.3
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    • pp.627-637
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    • 2023
  • Purpose To investigate the effect of patient positioning on tendinosis grade, visible range, and infraspinatus tendon (IST) thickness, and to determine the feasibility of internal rotation (IR) position to assess IST on ultrasound (US). Materials and Methods This study included 52 shoulders of 48 subjects who were evaluated for IST in three different positions: neutral position (N), IR, and position with the ipsilateral hand on the contralateral shoulder (HC). Two radiologists retrospectively graded IST tendinosis from grade 0 to grade 3 and the visible range from grade 1 to grade 4. The thickness of the IST was measured by another radiologist with a short-axis view. A generalized estimating equation was used for statistical analysis. Results The tendinosis grades were higher in the HC position than in the IR position, with a cumulative odds ratio of 2.087 (p = 0.004, 95% confidence interval [CI]: 1.268-3.433). The tendinosis grades in the HC position (p = 0.370) and IR position (p = 0.146) were not significantly different from those in the N position. The overall difference in IST thickness was significant (p < 0.001), but the visible range (p = 0.530) was not significantly different according to position. Conclusion Patient positioning significantly affected the grade of tendinosis and thickness but not the visible range of the IST. The IR position is a feasible position for assessing the IST on US.

The Effect of Smart Oreder Service on Satisfaction and Continuous Use Intention: The Moderating Effect of Personality Type (스마트 오더 서비스가 만족도와 지속사용의도에 미치는 영향: 성격유형의 조절효과)

  • Yea Ji Yeon;Cheol Park
    • Information Systems Review
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    • v.24 no.2
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    • pp.41-66
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    • 2022
  • With the development of IT, mobile apps and the expansion of contactless services due to COVID-19, "smart orders" have recently been activated in the food and beverage service. Even in recent years, when sales have declined, the number of orders made by smart orders has been steadily increasing, and this ordering method can accumulate customer data, enabling effective customized services in the future. In the present study, satisfaction with smart orders and continuous use intention were studied based on the technology acceptance model (TAM). And it focused on whether there is a difference in personality when using smart orders. For this purpose, a survey was conducted on 317 smart order users, and the hypothesis was verified by structural equation model analysis. Perceived benefits had a significant effect on satisfaction; also, satisfaction had a significant effect on continuous use intention. There is a significant disparity between introvert and extrovert type. As a consequence, the introverted type has a greater intention to perceive usefulness of smart orders and continuously use them. These results suggest that the customer's personality type should be considered in future customer customization strategies.

DEVELOPMENT OF HIGH SENSITIVE MODEL OF CARIES ACTIVITY TEST FOR EARLY DIAGNOSIS OF DENTAL CARIES (치아우식증의 조기진단을 위한 고감도 우식활성검사 모형개발)

  • Lee, Sang-Ho;Lee, Chang-Seop
    • Journal of the korean academy of Pediatric Dentistry
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    • v.27 no.1
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    • pp.169-179
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    • 2000
  • The purpose of this study is to develop the system which convert the optical difference of teeth texture between intact enamel and incipient caries lesion into shade difference by laser fluorescence and to develop new and simple caries activity test using laser fluorescence. The experimental design of this study consists of three parts. In first part, a new method for the in vitro assessment of changes in initial enamel caries lesion of Bovine teeth using laser fluorescence is tested. In second part, in vivo assessment undertaken. Number of teeth which showed incipient carious lesion on buccal surface examined by laser fluorescence was compared with the caries activity test of $Cariescreen^{(R)}$ test and other oral environmental test of dDfFtT. In third part, new caries activity test measured by laser fluorescence was developed on the basis of above results and evaluated the sensitivity, specificity, and diagnostic power. Optical density measured by laser fluorescence was increased as increasing the depth of incipient carious lesion and showed high correlation$(\gamma=0.7015)$ with lesion depth. Optical density showed direct proportion to lesion depth. Linear equation was obtained between the optical density and the lesion depth by regression analysis. The result of caries activity test with laser fluorescence showed high correlation with those of $Cariescreen^{(R)}$ test and dDfFtT examination. Caries activity test with laser fluorescence showed 48% of sensitivity, 52% of specificity, and 45% of diagnostic power on the basis of dDfFtT examination, and also showed 48% of sensitivity, 51% of specificity, and 36% of diagnostic power on the basis of $Cariescreen^{(R)}$ test. In regard above result, caries activity test with laser fluorescence considered to be reliable for caries activity test compared with other oral environmental test. and it was also considered to be practical because it would be simple, inexpensive, and time saving method.

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Runoff and Erosion of Alachlor, Ethalfluralin, Ethoprophos and Pendimethalin by Rainfall Simulation (인공강우에 의한 alachlor, ethalfluralin, ethoprophos 및 pendimethalin의 토양표면 유출)

  • Kim, Chan-Sub;Ihm, Yang-Bin;Lee, Young-Deuk;Oh, Byung-Youl
    • Korean Journal of Environmental Agriculture
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    • v.25 no.4
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    • pp.306-315
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    • 2006
  • Two different experiments, adsorption/desorption and runoff by rainfall simulation of four pesticides, such as alachlor, ethalfluralin, ethoprophos and pendimethalin were undertaken their runoff and erosion losses from sloped land and to assess the influence of their properties and environmental factors on them. The mobility of four pesticides and which phase they were transported by were examined in adsorption study, and the influence of rainfall pattern and sloping degree on the pesticide losses were evaluated in simulated rainfall study. Freundlich adsorption parameters (K) by the adsorption and desorption methods were 1.2 and 2.2 for ethoprophos, 1.5 and 2.6 for alachlor, respectively. And adsorption distribution coefficients (Kd) by the adsorption and desorption methods were 56 and 94 for ethalfluralin, and 104 and 189 for pendimethalin, respectively. K or Kd values of pesticides by the desorption method which were desorbed from the soil after thoroughly mixing, were higher than these ones by the adsorption method which pesticides dissolved in water were adsorbed to the soil. Another parameter (1/n), representing the linearity of adsorption, in Freundlich equation for the pesticides tested ranged from 0.96 to 1.02 by the desorption method and from 0.87 to 1.02 by the adsorption method. Therefore, the desorption method was more independent from pesticide concentration in soil solution than the adsorption method. By Soil Survey and Land Research Center (SSLRC)'s classification for pesticide mobility, alachlor and ethoprophos were classified into moderately mobile $(75{\leq}Koc<500)$, and ethalfluralin and pendimethalin were included to non-mobile class (Koc > 4000). Runoff and erosion loss of pesticides by three rainfall scenarios were from 1.0 to 6.4% and from 0.3 to 1.2% for alachlor, from 1.0 to 2.5% and from 1.7 to 10.1% for ethalfluralin, from 1.3 to 2.9% and from 3.9 to 10.8% for pendimethalin, and from 0.6 to 2.7% and from 0.1 % 0.3% for ethoprophos, respectively. Distribution of pesticides in soil profile were investigated after the simulated rainfall study. Alachlor and ethoprophos were leached to from 10 to 15 cm of soil layer, but ethalfluralin and pendimethalin were mostly remained at the top 5 cm of soil profile. The losses of the pesticides at 30% of sloping degree were from 0.2 to 1.9 times higher than those at 10%. The difference of their runoff loss was related with their concentration in runoff water while the difference of their erosion loss must be closely related with the quantity of soil eroded.

A Case Study on the Characteristics of the Road Traffic Noise in Plant Communities (학교 정온시설 앞 식물군락 조성지역에서 도로교통소음 특성에 대한 사례연구)

  • Cho, Il-Hyoung;Lee, Nae-Hyun;Cho, Jung-Sang;Ko, Jung-Yong;SunWoo, Young;Park, Young-Min
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.12
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    • pp.1293-1303
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    • 2006
  • This paper represents a comparison the difference between existence and nonexistence of soundproof trees for road traffic noise. Also we suggested that the simple equation has been derived using a single regression analysis for predicting levels of $Leq_{th}$ at a given distance from a road in terms of the flow rate, the mean speed of the traffic, and the percentage of the type vehicles in the existence and nonexistence of soundproof trees. We classified a vehicle into four and analyzed contribution rate to traffic volume. As a result, the order showed as followed: light vehicle>medium vehicle>heavy vehicle>motorcycle. However, the results of analyzing contribution rate with between traffic volume and traffic noise by the each type showed as followed; Motorcycle>Light vehicle>Medium vehicle>Heavy vehicle. This study showed that the most a lof of traffic volumes of the three vehicles(light vehicle, medium vehicle and motorcycle) and heavy vehicle were existed in 67 km/h and 61 km/h of car speed, respectively. The total traffic noise to the mean car speed decreased because of the inflow a lot of traffic volumes between 2016 and 2388 in the range of 67 km/h of light vehicle speed, in traffic composition of 4.75% heavy vehicles, and 1.11% motorcycle. the final result for this study showed that statistical paired t-test for between existence and nonexistence of soundproof trees was significant(p<0.05) and the difference between daytime and night in the location of the nonexistence of plant communities with the independent sample T-test was significant(p<0.05). However, the independent sample T-test for analyzing the variance of traffic noise between daytime and night was not significant(p>0.05).

Estimation of surface nitrogen dioxide mixing ratio in Seoul using the OMI satellite data (OMI 위성자료를 활용한 서울 지표 이산화질소 혼합비 추정 연구)

  • Kim, Daewon;Hong, Hyunkee;Choi, Wonei;Park, Junsung;Yang, Jiwon;Ryu, Jaeyong;Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.33 no.2
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    • pp.135-147
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    • 2017
  • We, for the first time, estimated daily and monthly surface nitrogen dioxide ($NO_2$) volume mixing ratio (VMR) using three regression models with $NO_2$ tropospheric vertical column density (OMIT-rop $NO_2$ VCD) data obtained from Ozone Monitoring Instrument (OMI) in Seoul in South Korea at OMI overpass time (13:45 local time). First linear regression model (M1) is a linear regression equation between OMI-Trop $NO_2$ VCD and in situ $NO_2$ VMR, whereas second linear regression model (M2) incorporates boundary layer height (BLH), temperature, and pressure obtained from Atmospheric Infrared Sounder (AIRS) and OMI-Trop $NO_2$ VCD. Last models (M3M & M3D) are a multiple linear regression equations which include OMI-Trop $NO_2$ VCD, BLH and various meteorological data. In this study, we determined three types of regression models for the training period between 2009 and 2011, and the performance of those regression models was evaluated via comparison with the surface $NO_2$ VMR data obtained from in situ measurements (in situ $NO_2$ VMR) in 2012. The monthly mean surface $NO_2$ VMRs estimated by M3M showed good agreements with those of in situ measurements(avg. R = 0.77). In terms of the daily (13:45LT) $NO_2$ estimation, the highest correlations were found between the daily surface $NO_2$ VMRs estimated by M3D and in-situ $NO_2$ VMRs (avg. R = 0.55). The estimated surface $NO_2$ VMRs by three modelstend to be underestimated. We also discussed the performance of these empirical modelsfor surface $NO_2$ VMR estimation with respect to otherstatistical data such asroot mean square error (RMSE), mean bias, mean absolute error (MAE), and percent difference. This present study shows a possibility of estimating surface $NO_2$ VMR using the satellite measurement.

Seasonal Variation of Thermal Effluents Dispersion from Kori Nuclear Power Plant Derived from Satellite Data (위성영상을 이용한 고리원자력발전소 온배수 확산의 계절변동)

  • Ahn, Ji-Suk;Kim, Sang-Woo;Park, Myung-Hee;Hwang, Jae-Dong;Lim, Jin-Wook
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.4
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    • pp.52-68
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    • 2014
  • In this study, we investigated the seasonal variation of SST(Sea Surface Temperature) and thermal effluents estimated by using Landsat-7 ETM+ around the Kori Nuclear Power Plant for 10 years(2000~2010). Also, we analyzed the direction and range of thermal effluents dispersion by the tidal current and tide. The results are as follows, First, we figured out the algorithm to estimate SST through the linear regression analysis of Landsat DN(Digital Number) and NOAA SST. And then, the SST was verified by compared with the in situ measurement and NOAA SST. The determination coefficient is 0.97 and root mean square error is $1.05{\sim}1.24^{\circ}C$. Second, the SST distribution of Landsat-7 estimated by linear regression equation showed $12{\sim}13^{\circ}C$ in winter, $13{\sim}19^{\circ}C$ in spring, and $24{\sim}29^{\circ}C$ and $16{\sim}24^{\circ}C$ in summer and fall. The difference of between SST and thermal effluents temperature is $6{\sim}8^{\circ}C$ except for the summer season. The difference of SST is up to $2^{\circ}C$ in August. There is hardly any dispersion of thermal effluents in August. When it comes to the spread range of thermal effluents, the rise range of more than $1^{\circ}C$ in the sea surface temperature showed up to 7.56km from east to west and 8.43km from north to south. The maximum spread area was $11.65km^2$. It is expected that the findings of this study will be used as the foundational data for marine environment monitoring on the area around the nuclear power plant.

A Study on the Analysis of Difference between IT and Non-IT Companies on the Smart Work Environment Continuous Use Intention - Focusing on Korean Small and Medium Enterprises (스마트워크 환경에서 지속사용의도에 대하여 IT기업과 비IT기업 간의 차이분석에 관한 연구 -한국 중소기업을 중심으로)

  • Jung, Soo-Yong;Shin, Yong-tae
    • Journal of Digital Convergence
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    • v.16 no.3
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    • pp.249-259
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    • 2018
  • This research had intended to find out regarding the present influences of the Smart Work on the intention to use continuously with the staff members working in the small- and medium-sized enterprises as the subject. And, finally, it had intended to find out about the Smart Work environments of the IT corporations and the non-IT corporations. For this research, the questionnaire survey data were collected from the staff members working at the small- and medium-sized enterprises. Through the questionnaire survey data that were collected, an empirical analysis was carried out. And, through the reliability analysis, the feasibility analysis, the discriminatory feasibility analysis, and the inspection of the degree of suitableness of the structural equation model, finally, the research model was verified and, finally, a difference analysis of the IT corporations and the non-IT corporations was carried out. Regarding the results of the analysis of the research, it appeared that the factors of the job efficiency and the job autonomy of the special characteristics of the job had the positive influences on the usefulness and the job satisfaction, which were the parameters and which were perceived. And it appeared that the time flexibility of the job form could not have any influences on the usefulness and the job satisfaction, which were the parameters and which were perceived. And it appeared that the spatial flexibility had the influences on the job satisfaction only. The perceived usefulness, which was a parameter, had the positive influences on the job satisfaction and the intention to use continuously. And, finally, the job satisfaction had the positive influences on the intention to use continuously. And it appeared that there were the differences, too, between the IT corporations and the non-IT corporations. It is thought that, through the results of this research and through the Smart Work environment, the positive influences on the workers and the organizations could be induced and that a better working environment than previously can be provided to the workers to fit the special characteristics of the corporations.

A Study of the Effect of Store Selection factors on the Customer's Satisfaction and Revisit Intention (한·중 대형마트 구매자 점포선택요인에 관한 비교연구)

  • Noh, Jung-Koo;Lee, Ji-Eun;WANG, Chun-Chun
    • Management & Information Systems Review
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    • v.33 no.5
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    • pp.97-115
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    • 2014
  • The purpose of this study is to illustrating how the store selection factors affect the customer's satisfaction about the store and the intention of revisit base on the analyzing the store selection factors. At the same time, the difference between the influence on the customer's satisfaction and revisit intention of that in Korea and in China is also compared. Accordingly, through the notional understanding of configuration variables and the investigation of previous research, the Research hypothesis was set and the relevance between the two was inspected. The survey was aimed at the Korean customers who visit the large supermarkets in Korea and Chinese customers who visit the large supermarkets in China. After that, the reliability and validity of the collected data was verified and the research hypothesis was validated by structure equation modeling. The result of this study can by concluded as follows: First, in Korea the customer's satisfaction is showed to be affected by store selection factors, product property, service property and physical environment. Second, in China the customer's satisfaction is showed to be affected by store selection factors, product property, service property and physical environment. Third, in Korea the revisit intention is showed to be affected by customer's satisfaction. Forth, in China the revisit intention is showed to be affected by customer's satisfaction. Fifth, it shows little difference between the store selection factors of the customers visiting large supermarkets in Korea and in China. According to the research results above, the implications can be drawn as the customer's satisfaction of those who visit the large supermarkets may be affected by store selection factors (store property, product property, service property and physical environment). In recent years, more and more overseas large supermarkets are opening in both Korea and China and the competition among each is become more intense day by day. Every larger supermarket is trying their best to refine their store property, product property, service property and physical environment, in order to enhance the customer's satisfaction. The biggest factor that affects the customer's satisfaction and revisit intention in Korea is service property, So that the services requires proper measures and improvement. In China, the factor that affects most on the customer's satisfaction and revisit intention is physical environment. In order to enhance the customer's positive consciousness of stores, the physical environment needs to be well constructed. Lastly, in the compared research between Korea and China, the distribution of survey responders was limited from certain areas. Therefore, the further study can be implemented by more research in various geographical areas and more development in store selection factors.

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The Effect of Geometric Factors When Measuring Standard Count for Radioactive Iodine Thyroid Uptake Rate (표준계수 측정 시 기하학적 요인이 방사성 요오드 갑상선 섭취율에 미치는 영향)

  • Oh, Joo Young;Kim, Jung Yul;Oh, Ki Baek;Oh, Shin Hyun;Kim, Jae Sam;Lee, Chang Ho;Park, Hoon-Hee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.1
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    • pp.53-61
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    • 2013
  • Objectives: It is certain that Radioactive iodine thyroid uptake(RAIU) rate should be measured with the standard counts considering the thyroid gland depth in enlarged thyroid patients for the variation from geometric factors. The purpose of this paper is to consider the effects of geometric factors according to detector to source distance and the effective thyroid depth on RAIU rate with experiment test. Materials and Methods: I-131 370 kBq ($10{\mu}Ci$) point source was measured by Captus-3000 thyroid uptake system (Capintec, NJ, USA) with a change Detector-Source Distance from 20 cm to 30 cm at an interval of 1 cm. And we changed the Neck phantom surface-Source Depth in the phantom with 1 cm, 2 cm, 5 cm using the neck phantom in order to reproduce the effective thyroid depth. Results: Every experimental group follows power curve as inverse square curve ($$R2{\geq_-}0.915$$). The average count rates in the case not using a phantom and the every case applied the effective thyroid depth using a phantom was not identical each other. There was significant fluctuations upon the effective thyroid depths applied the effective thyroid depth above 1 cm in $364.4 keV{\pm}10%$ energy ROI (p<0.01). There was not significant difference between the count rates of 1 cm and 2 cm in $364.4keV{\pm}20%$ and $637.1keV{\pm}6.2%$ (p=0.354, p=0.397). In assumed RAIU rate from regression equation, $364.4keV{\pm}20%$ was lower difference than $364.4keV{\pm}10%$ as 6.42% and 5.09% per 1 cm. Every change of count rate upon depth appears decreased line on Linear Regression, but the case of $284.3keV{\pm}10%$ increased only. And also, The graphs of coefficient of variation upon depth increased as straight line on every experimental group. Conclusion: The result appears that application of $364.4keV{\pm}20%$ energy ROI is more suitable for reducing error from the effective thyroid depth. And also, we can estimate the error of 20 cm should be highly reduced than 30 cm for Inverse Square Law. Therefore, If there is not information of the thyroid depth, it is considered that the error from thyroid depth can reduce through set up energy ROIs for $364.4keV{\pm}20%$, and increase Detector-Source Distances.

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