• Journal of Korean Ophthalmic Optics Society
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• v.19 no.3
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• pp.383-387
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• 2014

Purpose: To investigate the effect of corneal unique shape to changes of refractive full corrections when pupil size changes. Methods: Subjective refraction for monocular full correction was performed to 30 subjects ($23.33{\pm}1.78$ of age, 60 eyes) in two room conditions, 760 lx and 2 lx, respectively. Pupillary diameter was measured in two conditions and the change pattern was analyzed using a peak data of corneal topography. Results: Pupillary diameter was 3.74~4.00 mm in 760 lx and 5.52~5.90 mm in 2 lx. By comparison with refractive data in 760 lx, those data in 2 lx was changed as follows: more (-) spherical power of 17 eyes (28.3%), more (+) spherical power of 10 eyes (17.7%), more (-) cylinderical power of 17 eyes (28.8%), less (-) cylinderical power of 9 eyes (15.3%), and astigmatic axis rotation of 36 eyes (62.1%). From peak data of corneal topography, the changing pattern of two principal meridians was classified into 4 types. Conclusions: Expansion of the corneal refractive surface accompanied with pupillary dilation may be a main factor that effects the changing a values of subjective refraction because of unique corneal shape. Therefore, subjective refraction should be performed under the nearest lighting condition to a main living environment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.1-13
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• 1980

The purpose of the present study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by using three species of commercial fishes: filefish, Stephanolepis cirrhifer (Temminck et Schlegel), conger eel, Astroconger myriaster (Brevoort) and crucian carp, Carassius oarassius (Linnaeus). An experimental tank $(360L\times50W\times55Hcm)$ was set up in a dark room. An illumination system was attached to one end of the tank to control horizontal, light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish .in each section was counted 40 times every 30 seconds, and the gathering rates were obtain from the average number of fish in each section. In filefish the light intensity inducing maximum gathering rate was 0.7 lx(0.5-1.1 lx), and there nab little difference between day and night. Gathering rate varied propotionally to the length of illumination time. In conger eel the light intensities inducing maximum gathering rate were 1.9 lx(1.2-2.9 lx) in daytime and 5.2 lx (3.2-7.7 lx) at night. Thus, there was a considerable difference between day and night, but the gathering rate remained almost unchanged regardless to the length of illumination time. In crucian carp gathering rate did not show a definite pattern hut fluctuated irregularly. The gathering rate, however, was slightly higher at 16.21 lx, and there was little difference between day and night.

• Korean Journal of Ichthyology
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• v.19 no.3
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• pp.185-192
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• 2007

The present experiment was carried out to study the effects of light intensity on growth, survival, caudal fin shape, body composition, skin color and blood component of river puffer, Takifugu obscurus. Four light intensities (0, 500, 1,000, 2,000 lx) were tested in duplicates for 60 days. Specific growth rate (SGR), daily feeding rate (FR) and food coefficient (FC) were reduced following to the decrease of light intensity. However in survival rate there was not significantly different among groups. The damage extent of caudal fin was increased in more strong light intensity. In body composition, moisture and crude protein were only significantly difference according to light intensity. In body color, L and a were the highest in 0 lx. In blood analysis, the content of AST, ALT, GLU significantly increased in more powerful the intensity groups. It is concluded that the supplement of low light intensity (e.g. 0 lx) recommended for the commercial scale aquaculture of river puffer in land-based tank without growth and survival retardation.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.4
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• pp.549-554
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• 2013

Purpose: To determine the minimal illumination for visual acuity with the decimal vision chart and individual difference with varying contrast and illumination. Methods: Landolt's vision chart with 10 different grade of contrast was made. Minimal illumination was measured for 69 eyes using 100% contrast vision chart. Minimal contrast for identifying the chart was measured in conditions of the minimal illumination and 230 lx, respectively. Results: Minimal illumination was gradually increased with decrease of the chart size. Mean of minimal illumination to identify the 1.0 visual acuity was $74.39{\pm}25.90$ lx with range of 17~107 lx. In conditions of the minimal illumination and 230 lx, the minimal contrast for identifying the chart were gradually increased with decrease of the chart size in both conditions, the those deviation for 69 eyes was also increased. Conclusions: For refractive correction, examiners need to consider the individual difference for identifying the visual chart according to illumination and contrast.

• Korean Journal of Applied Biomechanics
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• v.24 no.2
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• pp.167-172
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• 2014

The purpose of this study was to investigate walking standard time and joint powers of the lower extremities on the changes of illuminations in the elderly women. Ten older women ($70.90{\pm}3.28$ years, $154.70{\pm}3.47$ cm, $53.80{\pm}5.39$ kg) with normal vision and no gait disabilities participated in this study. All the experiments were performed on a level walkway from low to high lighting (six conditions). A 3-dimensional motion capturing system, force-plate, and EMG were used to acquire and analyze walking motion, force, and muscle activity data; the sampling frequency was 100 Hz, 1000 Hz and 1000 Hz respectively. To test the differences on walking standard time and joint powers of the lower extremities between the six lighting conditions, one-way repeated ANOVAs were evaluated. The following results were drawn: First, mean standard time was about 1.3 sec/stride, and velocities were smaller with lighting increasing except 100 Lx. Second, the joint power patterns of ankle and knee were not consistent, but only hip joint power was a greatest in 6 Lx and a smallest in 400 Lx. Third, standard times(100 Lx<300 Lx, 400 Lx) were statistically significant, and hip joint max powers (100 Lx>others) were also statistically significant. But ankle and knee joint max power were not statistically significant. These results showed that standard times from low to high lighting were not consistent, and hip joint of 100 Lx has a greatest rotational torque. We suggested that gait strategies of them as to changing illuminations were not consistent and findings may represent a lack of adaptability in the elderly women.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.174-179
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• 2007

본 연구는 A체육대학교 옥내운동장 5곳을 선정하여 현재의 조명환경을 파악하고 수평면 및 수직면 조도를 측정하고 분석하였다. 고천장인 실내테니스장 배드민턴장, 핸드볼장과 저천장인 유도장과 탁구장을 선정하여 측정한 결과 평균조도는 실내테니스장 483[lx] 배드민턴장 272[lx], 핸드볼장 471[lx], 유도장 284[lx], 탁구장 370[lx]로 기준조도보다 상당히 낮게 측정되었다. 수직연 조도와 균제도도 권장치보다 낮게 나왔으나 연습경기장이므로 수평면조도를 충분히 보완한다면 연습하는 데는 큰 무리가 것으로 보인다. 전반적으로 조명환경이 열악하고 설비가 노후화되어 있으므로 시설보수 시 시뮬레이션을 활용하여 종목별 경기특성에 맞는 환경을 갖추도록 연구검토가 필요할 것으로 판단되었다.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.8 no.1
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• pp.29-36
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• 1994

Exhibitlon lighting design be done after due consideration of the photochemical reaction and heating effcts upon exposure to light In this study the balanced judgement is as follows. 'The most light-susceptible material should be illustrated less than 5O(lx](illumlnance-hours per year: 120,OOOlx.h)and the illuminance of moderately sensitive material is 200(lx] (illuminance hours per year: 480,OOOlx.h). Moreover to minimize damage the sources of light should not only contribute as little as heat possible but remove ultraviolt radiation by filters. Also the sources of light must have good color rendering and low color temperature.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.3
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• pp.9-20
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• 2016

This study compared the effect of green light consequent on maximum brightness 85 lx and intial brightness 15 lx, and its accompanying psychological, physiological response. 1) As a result of psychology(general stress evaluation, Symptom Checklist-90-Revision) evaluation, all stress evaluation items mostly showed a decrease, and they are comparatively positively evaluated in minimum brightness 15 lx comparing to maximum brightness 85 lx. 2) Physiological (Heart Rate Variability) evaluation result was included in stable range in all cardiovascular system variables after light stimulus in time of comparison with the standard range; in addition, the Heart Rate Variability evaluation result was found to be stable in all cardiovascular system variables except Low Frequency in minimum brightness 15 lx comparing to maximum brightness 85 lx. 3) Green light was found not to appear as a stimulating factor in the human body in time of space projection, being found to be effective in stability of mind and body, and reduction in stress. Thus, it was found that green light functioned as an emotional, relaxing tranquilizer by working on the sympathetic nervous system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.3
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• pp.259-267
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• 2023

At a time when the demand for drones is increasing, a plan to utilize drone images was sought for efficient promotion of cadastral resurvey. To achieve the purpose of this study, the technical and legal status of drone images was reviewed, and through this, the possibility of using it for cadastral resurvey was primarily reviewed. subsequently, an experiment was conducted targeting the project district to examine whether drone images were applied to boundary extraction, which is the primary process of cadastral resurvey. As a result of the experiment, it was found that boundary extraction from images is possible. However, in some cases, it is impossible due to field conditions or image quality. Therefore, it is necessary first to apply cases where boundary extraction is possible to cadastral resurvey and seek solutions for some impossible cases. In particular, the image quality problem may have problems with the current technology, but it will also have problems with the existing drone equipment. So, standard for drone calibration should also be established. Finally, the cadastral resurvey surveying procedure using drones was also presented

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.2
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• pp.146-155
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• 2004

Currently most of commercial operating systems contain a high-level audit feature to increase their own security level. Linux does not fall behind the other commercial operating systems in performance and stability, but Linux does not have a good audit feature. Linux is required to support a higher security feature than C2 level of the TCSEC in order to be used as a server operating system, which requires the kernel-level audit feature that provides the system call auditing feature and audit event. In this paper, we present LxBSM, which is a kernel module to provide the kernel-level audit features. The audit record format of LxBSM is compatible with that of Sunshield BSM. The LxBSM is implemented as a loadable kernel module, so it has the enhanced usability. It provides the rich audit records including the user-level audit events such as login/logout. It supports both the pipe and file interface for increasing the connectivity between LxBSM and intrusion detection systems (IDS). The performance of LxBSM is compared and evaluated with that of Linux kernel without the audit features. The response time was increased when the system calls were called to create the audit data, such as fork, execve, open, and close. However any other performance degradation was not observed.