• International Journal of Computer Science & Network Security
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• 제21권8호
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• pp.308-316
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• 2021

During the past two years, the education systems in the world witnessed unprecedented turmoil due to the coronavirus (Covid-19) pandemic, as most schools and universities in the world closed their doors to more than 1.5 billion students, or more than 90% of the total learners, according to recent figures issued by the UNESCO Institute for Statistics. Education experts have agreed that post- coronavirus education will not be the same as before, especially with the increasing use of modern technology in education. One of the most important new patterns with a structure digital in education is distance education, this style has been used, in many countries of the world, as an alternative to traditional education, since the beginning of the pandemic. In Saudi Arabia, this type of education has been used in all educational institutions, starting from kindergarten until the postgraduate level, as an alternative to face-to-face education to preserve the health and safety of students and workers in educational institutions. This study aimed to explore the level of satisfaction of preparatory year students on distance learning in their first year of study at Umm Al-Qura University. The findings of this study showed that students in the preparatory year were satisfied with their online learning experience. In addition, the results revealed that there was no effect for gender and location of study on students' level of satisfaction. Saudi universities should continue to work to create a suitable learning environment for students at the e-learning level.

• 정보보호학회논문지
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• 제21권6호
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• pp.153-160
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• 2011

최근 테러와 범죄의 증가로 CCTV와 같은 영상 감시시스템의 도입이 활발하게 이루어지고 있다. 동시에 감시카메라를 활용한 원거리 얼굴인식에 대한 관심도 증가하고 있다. 본 논문에서는 주성분 분석기반 얼굴인식기와 보간법을 이용해 거리별 얼굴인식률의 변화를 분석해보았다. 실험에 사용된 보간법은 최근접 이웃, 양선형, 양3차회선, Lanczos3 보간법이다. 실험결과 기존의 보간법 기술이 주성분 분석기반 원거리 얼굴인식기의 인식률에 미치는 영향은 적은 반면에, 거리별 얼굴영상을 학습영상에 포함시키면 주성분 분석기반 얼굴인식기의 인식률을 향상시킴을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제4권1호
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• pp.31-40
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• 1991

Four pairs of draught oxen (two local and two Jersey crossbred) were studied when they ploughed dry land on local farms. Work done, distance traveled and body temperature of each ox were measured continuously over a 5 h working day. A different team worked each day, completing at least six days work each. Individual food intakes and digestibility of feed were measured when the animals were given rice straw and tree fodder, and housed and fed according to local husbandry practices. The Jersey crossbreds, particularly the longer legged type, had a higher rate of work than the local oxen in this study. They did significantly more work and covered a greater distance during the day. The absence of a hump in the crossbred oxen had no effect on the position of the yoke or the way the oxen pulled when ploughing. The longer legged type of Jersey crossbred tended to work more erratically than any of the other teams. A fast rate of work made the oxen more liable to heat stress. When fed according to local practices and given the same amount of feed as local oxen, Jersey crossbreds tended to do less well. During the ploughing months, the local oxen gained weight, while the crossbreds remained at the same or lost some weight. Although there were some disadvantages to keeping Jersey crossbreds for work, their favourable work output suggests that the introduction of the Jersey crossbred in the hills of Nepal is unlikely to be detrimental to the performance of the work oxen population.

• The Journal of Asian Finance, Economics and Business
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• 제7권2호
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• pp.221-228
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• 2020

This study suggests an alternative to the conventional collaborative filtering method for predicting consumer choice, using case-based reasoning. The algorithm of case-based reasoning determines the similarity between the alternative sets that each subject chooses. Case-based reasoning uses the inverse of the normalized Euclidian distance as a similarity measurement. This normalized distance is calculated by the ratio of difference between each attribute level relative to the maximum range between the lowest and highest level. The alternative case-based reasoning based on similarity predicts a target subject's choice by applying the utility values of the subjects most similar to the target subject to calculate the utility of the profiles that the target subject chooses. This approach assumes that subjects who deliberate in a similar alternative set may have similar preferences for each attribute level in decision making. The result shows the similarity between comparable alternatives the consumers consider buying is a significant factor to predict the consumer choice. Also the interaction effect has a positive influence on the predictive accuracy. This implies the consumers who looked into the same alternatives can probably pick up the same product at the end. The suggested alternative requires fewer predictors than conjoint analysis for predicting customer choices.

• 오토저널
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• 제11권1호
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• pp.51-56
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• 1989

This study was performed to investigate the effect of defect on fatigue strength under the stress of rotary bending. The specimens were made of low carbon steel having artificial microholes, namely, single micro-hole and two adjacent micro-holes as natural defects, and the effects of the diameter of hole and the distance between the holes on fatigue strength have been investigated. The obtained result can be summarized as follows: 1, The critical defect means the largest size of defect that does not affect fatigue limit, and correspondes to the size of defect leading to final fracture under fatigue limit of smooth specimen. The size of defect which has an effect on fatigue limit is larger than that of critical defect. 2, The defect larger than the critical defect affects fatigue strength for as a kind of size effect, and the physical meaning of size effect of defect is considered same as the one of notch effect.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.6-14
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• 2007

The objective of this research is to comparative LCA(life cycle assessment) between two different model of Electric Motor Unit(EMU).the environmental impact of Aluminum body Electric Motor Unit(EMU) and Stainless Steel(STS) body Electric Motor Unit(EMU). LCA process consists of four steps which are goal, scope definition, life cycle impact analysis(LCIA) and life cycle interpretation. ISO 14044 provides the LCA standard method which can be conducted by using comparative LCA. From the research it is foung that the Aluminium Body Electric Motor Unit (EMU) is 3.6ton heaver than Stainless Steel(STS) body Electric Motor Unit(EMU). The system boundary of both Electric Motor Unit (EMU) are same life span and travel same distance. These both Electric Motor Unit (EMU) has same kind of environmental impact which is maximum Ozone Depletion(OD). During using period of these two models, the Aluminium Body Electric Motor Unit(EMU) has more global warming(GW) effect but Stainless Steel(STS) body Electric Motor Unit(EMU) has more Ozone Depletion(OD) effect. The above result is obtained by using LCA software PASS verson 3.1.3.

• 한국포장학회지
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• 제7권2호
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• pp.25-30
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• 2001

Corrugated board is composed of cellulose fibers which are arranged with the same direction as the board manufactured. The direction is classified with machine direction (MD) and cross-machine direction (CD). Therefore, corrugated board is orthotropic material that has totally different strength properties at each direction and especially, at machine direction, the mechanical properties of fiberboard is superior. The compression strength of the corrugated fiberboard boxes is very important information to the manufacturers and the end users. This study was carried out to design the optimum pattern, size, and location of ventilating hole for ventilating container through the finite element analysis. The optimum pattern and location of ventilating and hand hole were vertical oblong, a short distance to the right and left from the center of panel, and center or a short distance to the top of both sides, respectively. We identified the effect on both stress dispersion and stress level from the analysis of redisigned hand hole.

• 천문학회지
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• 제33권3호
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• pp.151-158
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• 2000

We conducted a deep CCD observations in V band to obtain stellar density distribution and to determine the distances toward two molecular clouds with anomalous velocity in the Galactic anti-center region. Star count method based on the linear programming technique was applied to the CCD photometric data. We found two prominent peaks at distances of around 1.4 and 2.7 kpc. It is found that the first peak coincides well with stellar density enhancement of B8-A0 stars and the second one with the outer Perseus arm. The effect of the choice of the luminosity function is discussed. The stellar number density distribution is used to derive the distances to the molecular clouds and the visual extinctions caused by the clouds. We found that two molecular clouds are located almost at the same distance of about 1.1 $\pm$ 0.1 kpc, and the peak extinctions caused by the clouds are about 2.2 $\pm$ 0.3 mag in V band.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.119-125
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• 2000

In this study, field measurements and analysis of vibration before and after the installation of continuously welded rail were performed. The vibration data obtained at the same locations before and after were analyzed to find out the characteristics of vibration level. The component of train-induced impulsive vibration at the rail joints varies depending upon the distance from the source, however mostly low frequency vibration which propagates long distance causes the problems of vibration. Even though it is expected that there may be certain degree of discrepancy in the amount of reduction in vibration depending upon site ground conditions, it was found that installation of continuously welded rail shows reduction in train-induced vibration.

• 천문학회지
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• 제29권2호
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• pp.269-278
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• 1996

We present the color-magnitude diagrams (CMD) of more than 24,000 stars in the field of an intermediate age open cluster M11, based on wide field CCD imaging. The morphology of the CMDs varies strikingly as the distance from the center of the cluster increases. From the surface number density analysis, we confirm the mass segregation effect in this cluster: the bright, massive stars are centrally more concetrated than the faint, low mass stars. The slope of the field-corrected surface density with respect to magnitude progressively increases as the radius increases, up to r = 5'. Most of the field stars in or near the cluster main sequence band and in the bright part of the red stars in the CMDs appear to be nearly at the same distance as M11, and they are considered to be the major component of disk stars in the Sagittarius-Carina arm.