• 제목/요약/키워드: Period of use

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A Study on the Comparison of Electricity Forecasting Models: Korea and China

  • Zheng, Xueyan;Kim, Sahm
    • Communications for Statistical Applications and Methods
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    • v.22 no.6
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    • pp.675-683
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    • 2015
  • In the 21st century, we now face the serious problems of the enormous consumption of the energy resources. Depending on the power consumption increases, both China and South Korea face a reduction in available resources. This paper considers the regression models and time-series models to compare the performance of the forecasting accuracy based on Mean Absolute Percentage Error (MAPE) in order to forecast the electricity demand accurately on the short-term period (68 months) data in Northeast China and find the relationship with Korea. Among the models the support vector regression (SVR) model shows superior performance than time-series models for the short-term period data and the time-series models show similar results with the SVR model when we use long-term period data.

A Study on the Spatial Use Patterns of the Demented Elderly in Skilled Nursing Facilities (노인전문요양시설 치매노인의 공간이용패턴에 관한 연구)

  • Yang, Kum-Suek
    • Journal of the Korean Institute of Rural Architecture
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    • v.8 no.2
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    • pp.36-45
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    • 2006
  • The purpose of this study is to clarify the spatial use pattern changes over time in skilled nursing facility. The investigation had been executed against the elderly(65 and over) in skilled nursing facility. This article discuss the basic characteristics of the elderly with dementia and the daily living activities of the elderly with dementia at skilled nursing facility in Jangseong-gun. The survey was repeated 2 times at the period of 61 months and 88 months after the opening of the facility. Changes over time of the spatial use patterns are clarified. Some results show as follows: (1)As the time went by, there is wide difference between behavioral places and nursing levels on the living activities of the elderly with dementia. (2)As the time went by, the elderly who have a tendency to stay in his bedroom through the greater part of the days.

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Analysis of Irrigation Water Use from Pumping Station (양수장 지구를 대상으로 한 농업용수 이용특성 분석(관개배수 \circled2))

  • 박기욱;정하우;석대식
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2000.10a
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    • pp.169-174
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    • 2000
  • The analysis of irrigation water use characteristics from a pumping station is implemented. Sangjoo district was selected as a test area. Irrigation water are varied according to manners of water manager, weather change and irrigation system changes such as the repair and improvement of irrigation canal, installation of an auxiliary water sources and canal structure. From the results, average irrigation water is 1,136mm during irrigation period from 1987 to 1997 in sanjoo district. After improvement of irrigation district, irrigation water was increased 45% as average water use in this area.

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A Study on Project Scheduling under Multiple Resource Constraints (다수 자원제약 하에서의 프로젝트 일정계획에 관한 연구)

  • Lee, Jeong-Hun;Kim, Pan-Sool;Moon, Il-Kyeong
    • Journal of Korean Institute of Industrial Engineers
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    • v.36 no.4
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    • pp.219-229
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    • 2010
  • The PERT/CPM are considered as the base procedures for the most successful project scheduling programs. Unfortunately, it is not easy to apply these procedures to real-life projects. This is due to the fact that PERT/CPM assume an infinite number of resources for each activity in project networks. Obviously, the completion time under no constraints is less than when constraints are imposed. One way of approaching this problem is to use heuristic solution techniques. In this paper, we present three heuristics; MRU (Maximum Resource Use) rule, STU (Shortest Time Use) rule, MRUP (Max Resource Use and Period) rule for allocating resources to activities of projects under multiple resource constraints. Comparisons of the project durations show that these heuristic rules are superior to AG3 rule that has been widely used in practice (Elsayed and Boucher, 1994).

Investigation of Irrigation Water Use in Sumjin River Basin

  • Choi, Jin-Kyu;Yoon, Kwang-Sik;Choi, Soo-Myung;Park, Seung-Woo;Son, Jae-Gwon;Koo, Ja-Woong
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42
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    • pp.1-8
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    • 2000
  • To examine the irrigation water uses in Sunjin river basin, existing status and operation records of headworks facilities including reservoirs, pumping stations, tube wells, and diversion dams were surveyed and analyzed for the period of 1994∼1998. Daily irrigation demand and water use were estimated for the irrigated paddy field using penman equation, Thank model, reservoir water balance model and daily pumping rate of pumping stations. Irrigation water use from multi-purpose dams in the basin was not included in this study.

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A Investigation for Usage Reason and Usage Satisfaction of Setting Perm and Digital Perm (셋팅 펌과 디지털 펌 기기의 사용 이유와 사용 만족도 조사)

  • Hong, Mi Ra;Park, Hye ryeon;Youn, Young Han
    • The Journal of the Korea Contents Association
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    • v.20 no.6
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    • pp.312-325
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    • 2020
  • The heat perm is the preferred hair technique to get positive affects such as increase of work efficiency and sale in hair industry. The subjects of this study is 262 hair shop workers and it was investigated heat perm device using reason, using satisfaction and repurchase. As a result, the perm accounted for 32.1 and the use of digital perm devices was more than that of setting perm devices. The reasons for the use were that the longer the setting device was engaged, the flexible it was the hair wave. The higher the rank, the better the hair wave retention and the long hair treatment, and it also helped sales. (p<0.05) Digital perm device can be hair-wavy in the desired style while in use, and the longer the working period, the more advantageous. The repurchase intention was that the longer the period of service and the higher the rank, the more advantageous it was. (p<0.05) The reasons for the usage of setting perm and digital perm were correlated with the satisfaction of use and the repurchase intention. The reasons for the use were helpful for sales and elastic hair wave and long hair waving was possible, which affected the repurchase. In conclusion, heat perm had been found not only helped sales, made a good hair wave, and the long hair waving, but also to be preferred to the long working period of the hair shop and the rank above the designer.

Monitoring Land-use Changes by Remote Sensing and GIS Techniques: Case Study of Barind Tract, Bangladesh

  • Sohel, Md. Shawkat Islam;Rana, Md. Parvez;Islam, A.Z.M. Zahedul;Akhter, Sayma
    • Journal of Forest and Environmental Science
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    • v.27 no.2
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    • pp.73-79
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    • 2011
  • The Barind tract is threatened by desertification and undergoing rapid change. In view of this fact it is very much essential to manage this barind tract under proper land-use plan. The present study evaluates the effectiveness of high-resolution satellite data and computer aided GIS techniques in assessing land-use change detection for the period 1990 to 2007 within the study area, which is very much essential to manage this barind tract under proper land-use plan, and for proper land-use plan it is necessary to get reliable information. The present study found five major land-use such as current fallow, current agriculture, settlement, irrigation water and water bodies. From the result, it is found that current fallow and water bodies decrease while settlement and current agriculture increase. Study concludes that as Barind tract is threatened by desertification, decrease of water bodies is not a good sign for the study area.

The comparison of muscle activity according to various conditions during smartphone use in healthy adults

  • Kim, You Lim;Yoo, Jaehyun;Kang, Sinwoo;Kim, Taerim;Kim, Namyeol;Hong, Sojeong;Hwang, Wonjeong;Lee, Suk Min
    • Physical Therapy Rehabilitation Science
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    • v.5 no.1
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    • pp.15-21
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    • 2016
  • Objective: The purpose of this study was to see the changes in muscle activity of the upper limb in persons using a smartphone. Design: Cross-sectional study. Methods: An experiment was conducted to target 15 right-handed university students. Experiments were carried out for students using cell phones for more than a year. In this study, experiments were carried out with one-handed and both handed operation of smartphone use in a sitting position, the same parameters with smartphone use in a standing position. The experiments were carried out by having the subjects write a text message in Korean on the smartphone for 3 minutes repeated 3 times with a rest period of 10 seconds given between each 3 minute period. Electromyography (EMG) was used to record the muscle activity of the upper trapezius (UT), extensor carpi radialis (ECR), and abductor pollicis (AP) during phone operation. Results: The muscle activity of the AP and ECR were significantly higher during single handed compared to double handed in both sitting and standing position (p<0.05). The muscle activity of the ECR was significantly higher in standing position compared to sitting position with double handed use of the smartphone (p<0.05). UT muscle activity of the right has been activated more than twice compared to the left UT in a sitting position (p<0.05). And UT muscle activity on the right has been activated more than five times compared to the left in a standing position (p<0.05). Conclusions: Using smartphone with double hand is useful for the prevention of musculoskeletal disorders.

A Numerical Simulation for Thermal Environments by the Modification of Land-use in Busan (부산지역 토지이용(land-use) 변화에 의한 열환경 수치모의)

  • 김유근;문윤섭;오인보;임윤규
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.6
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    • pp.453-463
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    • 2002
  • Prognostic meteorological model, MM5V3 (Mesoscale Model 5 Version 3) was used to assess the effects of the land-use modifications on spatial variations of temperature and wind fields in Busan during the selected period of summer season in 2000. We first examined sensitivity analysis for temperature between MM5V3 predictions and meteorological data observed at 4 AWS (Automatic Weather System) stations in Busan, which exhibited low structural and accurate errors (Mean Bias Error, MBE: 0.73, Root Mean Square Error, RMSE: 1.18 on maximum). The second part of this paper, MMSV3 simulations for the modification of land-use was performed with 1 km resolution in target domain, 46$\times$46 $\textrm{km}^2$ area around city of Busan. It was found that modification result from change of surface land-use in central urban area altered spatial distributions of temperature and wind. In particular, heat island core moved slightly to the seaward at 1300 LST. This results may imply that modification of surface land-use leads to change the thermal environments; in addition, it has a significant effect on local wind circulations and dispersions of air pollutants.

The Impact of Technostress on Telemedicine App Usage Intentions in the Post-COVID19 Era (포스트 코로나 시대의 원격진료 앱 사용 의도에 대한 연구: 테크노 스트레스의 영향을 중심으로)

  • Dong-eon Lee;Se-Youn Jung
    • Journal of the Korea Safety Management & Science
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    • v.26 no.1
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    • pp.1-8
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    • 2024
  • This study explores the impact of technostress on the intention to use telemedicine applications (apps) in the post-COVID19 era, a period marked by the rapid popularization of such apps to mitigate COVID19 infection risks. Utilizing the Technology Acceptance Model (TAM), the study identifies variables and proposes a research model. A questionnaire survey involving 364 adults is analyzed through Partial Least Squares-Structural Equation Modeling. Results indicate positive significance for variables linked to the TAM (perceived usefulness, perceived ease of use, attitude, and intention to use). Notably, techno-complexity negatively affects perceived ease of use, while techno-unreliability negatively impacts perceived usefulness and ease of use. Surprisingly, techno-uncertainty has a positive effect on both perceived usefulness and ease of use. Techno-overload, although negatively impacting perceived usefulness and ease of use, does not reach statistical significance. The study underscores the need to consider both positive and negative aspects, including technostress, when evaluating telemedicine app usage. Additionally, recognizing the varying impact of technostress based on users' ICT(Information and Communication Technology) confidence levels is crucial. Overall, these findings contribute academically to telemedicine app adoption literature and hold industrial significance by providing a user perspective on these apps.