• Journal of the Ergonomics Society of Korea
• /
• v.34 no.2
• /
• pp.191-198
• /
• 2015

Objective: As a cue for desired mood, we attempted to identify types of sitting postures when people are involved in various tasks during their working hours. Background: Physical behaviors in reaction to user contexts were studied, such as automated posture analysis for detecting a subject's emotion. Sitting postures have high feasibility and can be detected robustly with a sensing chair, especially when it comes to an office. Method: First, we attached seven sensors, including six pressure sensors and one distance sensor, to an office chair. In Part 1, we recorded participants' postures while they took part in four different tasks. From the seven sensors, we gathered five sets of data related to the head, the lumbar, the hip, thigh pressure and the distance between the backrest and the body. We classified them into four postures: leaning forward, upright, upright with the lumbar supporting, and leaning backward. In part 2, we requested the subjects to take suitable poses for the each of the four task types. In this way, we compared the matches between postures and tasks in a natural setting to those in a controlled situation. Results: We derived four types of sitting postures that were mapped onto the different tasks. The comparison yielded no statistical significance between Parts 1 and 2. In addition, there was a significant association between the task types and the posture types. Conclusion: The users' sitting postures were related to different types of tasks. This study demonstrates how human emotion can interact with lighting, as mediated through physical behavior. Application: We developed a posture-based lighting system that manipulates the quality of office lighting and is operated by changes in one's posture. Facilitated by this system, color temperatures ranging between 3,000K and 7,000K and illuminations ranging between 300lx and 700lx were modulated.

• Journal of the Korea Safety Management & Science
• /
• v.12 no.4
• /
• pp.41-51
• /
• 2010

This paper describes the development of various lighting equipment adapting Ultra Constant Discharge Lamp that has newly been on commercial supply in the market. Meeting the required conditions of lighting equipment, various types of UCD Lamp equipment with excellent performances could be successfully developed. In order to provide a guideline for the economical lighting product selection, the analyzed data comparison between Hi-pressure Sodium Lamp which has been the most popular lamp for street lighting and UCD Lamp is provided. The conclusions of the study are made as follows; (1) The performance measurement result of UCD Lamp shows excellent Luminous Efficacy as 108Lm/W, daylight-like Color Rendering Index as 90Ra, and the best operating temperature range as $-50^{\circ}C{\sim}+85^{\circ}C$. Comparing to the Hi-pressure Sodium Lamp, UCD could be evaluated as much superior products. (2) In an assembled status with the lighting fixture (Type STB형-60W), UCD Lamp was tested OK for one hour duration at the temperature range form $-50^{\circ}C$ to $+85^{\circ}C$ and the humidity of 98%. The operation at the extremely low temperature can be an excellent feature to enable the export to the cold temperature regions such as Northern Europe and Russia and the specific applications for defense systems and special industry. (3) As UCD Lamp is a genuine Korea made product following Energy-saving and Eco-friendly policy, it should be appreciated as one of the best $CO^2$ reduction Green product.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.8 no.1
• /
• pp.19-26
• /
• 2014

The purpose of this study was to investigate the human body effect according to micro bubble and LED lighting in half body bathing. This study was conducted on 6 elderly male and 7 female in 70's, and the subjects were classified into half body bathing with the micro bubble group (3 male, 4 female) and without the micro bubble group (3 male, 3 female) to proceed to the experiment. Experiments were performed 4 times by changing the LED lighting colors. As a result, parasympathetic nerves were activated than sympathetic nerves (micro bubble stimulation : 21.41%) and the temperature of the body were increased by $5.93^{\circ}C$ with micro bubble and red lighting stimulation. It is considered that this work will help to utilize the half body bathing system for the micro bubble and LED lighting.

• Proceedings of the Korea Contents Association Conference
• /
• 2008.05a
• /
• pp.203-207
• /
• 2008

The production process of the 3D-animation roughly consists of the pre-production, the main-production and the post-production. The pre-production, which is not only the outset of whole procedure among them but also the process to predict and design overall plan collectively is the most important step. A much more specific and perfect pre-production structure is needed to produce a high quality 3D-animation. Moreover, the standard 3D efficient lighting model is gathering strength as 2D and 3D artworks which are completed in this step maintain colors and looks in the main as well as post-production consistently. This study will make up for the weak points and help both to predict the color range of the overall 3D-animation product and to promote the application range of the 3D lighting system on the pre-production stage by developing the standard 3D lighting model applicable on the early step and calculating its lighting parameter properties.

• The Journal of the Korea Contents Association
• /
• v.19 no.7
• /
• pp.291-303
• /
• 2019

For cities with ancient buildings at core areas, night lighting is an effective means to demonstrate their history and culture. In this regard, night scenes of these ancient buildings are evaluated from multiple aspects, such as color rendition, brightness ratio affected by ambient light and technological realization of lighting facilities. This study builds a visual evaluation system for night scenes of ancient buildings based on three dimensions, namely ancient architecture carrier performance, visual perception and technological realization, and explains specific evaluation sub-criteria one by one. In addition, this study adopts Analytic Hierarchy Process (AHP) to analyze the impact of each sub-criteria item on the weight of the whole evaluation system, and conducts a consistency test to show that the evaluation system meets the reasonable requirements of hierarchy setting. Moreover, relative importance of each sub-criteria item may be determined based on their corresponding weights.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.6
• /
• pp.706-713
• /
• 2020

To control the LED lighting for broadcasting, LED current control using tri-stimulus values is used for RGB LEDs. For the convenience of control, this control is approximated as a linear function or used as an appropriate value through trial and error. Also, it is not suitable for broadcast lighting because it does not use a diffuser plate applied for mixing sufficient light and color required for actual it. In this study, a neural network with excellent nonlinear function approximation is used as a control method for LED panels for broadcast lighting. We intend to implement an LED panels controller suitable for the desired chromaticity coordinates and dimming values of intensity. As a result of the performance evaluation, the errors of the xy chromaticity coordinates are mostly ±0.02 and the acceptable range of ANSI C78.377A was satisfied. The average errors of the xy chromaticity coordinate are xerror=0.0044 and yerror=0.0030, respectively, and we confirmed the superiority and stable performance of the proposed algorithm.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.43 no.3 s.309
• /
• pp.67-75
• /
• 2006

Facial expressions exhibit not only facial feature motions, but also subtle changes in illumination and appearance. Since it is difficult to generate realistic facial expressions by using only geometric deformations, detailed features such as textures should also be deformed to achieve more realistic expression. The existing methods such as the expression ratio image have drawbacks, in that detailed changes of complexion by lighting can not be generated properly. In this paper, we propose a nonlinear model for skin color change and a model-based synthesis method for facial expression that can apply realistic expression details under different lighting conditions. The proposed method is composed of the following three steps; automatic extraction of facial features using active appearance model and geometric deformation of expression using warping, generation of facial expression using a model for nonlinear skin color change, and synthesis of original face with generated expression using a blending ratio that is computed by the Euclidean distance transform. Experimental results show that the proposed method generate realistic facial expressions under various lighting conditions.

• Science of Emotion and Sensibility
• /
• v.14 no.1
• /
• pp.59-72
• /
• 2011

Since stress can cause a variety of diseases, the relaxation of stress is an important factor for preventing diseases. One way to relieve stress is to use auditory or visual materials. If auditory and visual ones are used together, the effect of stress relaxation will be maximized. In this context, we analyze mood distribution of genre of music and color distribution of mood from the mood data for musics and color data for mood words collected directly from volunteers. Based on these two distributions, we also perform the $X^2$-test with Minitab for checking that color distributions are different from genre to genre. The results show that a different genre has a different color distribution and that the distributions of color, brightness and saturation depend on mood (P<0.0001). The results will be used to develop an emotional lighting system which plays lighting according to music mood, which can be applied to psychotherapy but more data and analysis are needed for clinical trials.

• Journal of the Semiconductor & Display Technology
• /
• v.5 no.2 s.15
• /
• pp.15-18
• /
• 2006

This paper presents a optimizing algorithm getting through analyzing a image improvement algorithm using retinex theory. Improving a existing retinex theory's slow process speed, our proposal is that it controls a small filter size of surrounding function by comparing with original algorithm. So slow process speed decreased drastically. For filling a short of lighting information by small filter, we also selected gray image as a forth channel. Using the color constancy, we got fast process time like linear color correction and could do comfortable auto color rectification according to other images.

• Journal of the Korean Society of Industry Convergence
• /
• v.15 no.3
• /
• pp.87-94
• /
• 2012

Kruithof demonstrated the preferred combination of illuminance levels and color temperatures. However, as Benett pointed out, difference of themal variables in such preference may be expected. The purpose of this study is to clarify the combined effects of lighting conditions(illuminance, color temperature), operative temperature on the human physiological and psychological responses. In order to observe operative temperature change in preference of color temperatures for three illumination levels, three subjects were exposed to two different conditions of color temperatures of 2,850K, 4,200K and 6,850K combined with operative temperatures(OT) of $25{\sim}31^{\circ}C$ at 100~1000lx. Thermal sensation vote and comfortable sensation vote, brightness perception vote were reported in each experiment conditions. The following results were obtained : 1) When illuminace level was at 100lx in operative temperatures of OT $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, Color temperature affect not themal sensation but Warm-cool sensation. 2) Operative temperatures affect not brightness perception vote but visual comfort sensation vote, satisfactive sensation vote, warm-cool sensation vote and themal sensation vote.