A noble method was developed for determining indoor greenery ratio through a digital camera and image analysis. Photographs with 10 different exposure compensations level were taken at indoor room using the function of “Partial color (green)” in a digital camera under varied indoor light conditions. RGB photographs were converted into Lab mode using [Image/Mode] function of Photoshop software program. The number of green pixels were calculated within 1 to 127 level (equivalent to -127 to -1 of Hunter a* value) through “Channel a” in [Histogram] function of the software. Greenery ratio was calculated by maximum green pixel number of an exposure compensation in relation to total pixel number, as maximum green pixels number would be obtained under a certain exposure compensation level when it minimizes achromatic color by partially excessive lower or higher light condition within certain area of photograph. When greenery ratio obtained from this method was compared with general greenery calculation of green area through manual selection, coefficient of determination was 0.9852, indicating appropriate greenery ratio estimating method. When applied to vertical planter of veranda and office, greenery ratio varied at 0.53～14.96%. In our experimental condition, error of the function, “Partial color” by the digital camera was within 0.013, while the error of the function, “Channel a” by the software was within 0.005.

This study was taken place to find out the psychological change with comparing before and after the experience of installation of indoor garden with 55 of subjects out of 62 subjects. More than 50% of subject answered that the garden management would be difficult before they experience the installation but the pressure was decreased while the interest of plants and landscape increased, however, the burden of management decreased and the interest in the kinds of plants and landscape design tended to increase after the experience of the installation. The psychological effect of indoor garden of workers was significantly increased with the question of “Indoor garden improves effect of air cleaning.” after the experience of installation and the loyalty was statistically increased with the question of “Intend to invest more fund to purchase indoor plant” (p <.05). As a result of the comparison of two psychological indicators, the recovery index of the state according to experience of indoor gardening was significantly higher after experiencing the indoor garden than before the indoor gardening experience. As the result of sensibility evaluation of pleasant, natural and calm with semantic differential method, workers feel more of them with the indoor garden. In addition, the loyalty was statistically significantly higher in the question “I would be willing to invest more in plant purchase” after experiencing the composition indoor garden (p <.05). This result is similar to the result that the resident’s recovery index, pleasantness, calm feeling, and emotional index are higher the indoor garden in public resting area with indoor garden than without indoor garden. With this study, the perception of indoor garden changed as a result of the worker’s experience of indoor gardening in the workplace and the view of the indoor garden created by the workers. As the psychological healing effect of indoor garden increased, increase in the cost investment for the emotional health promotion of the workers is expected to have a positive effect on the increase of the indoor garden.

The study was surveyed to 269 respondents for investigating psychological response to indoor foliage plants grouped by four type of design materials. 21 indoor foliage plants grouped as filler, mass, form, and line plant, are shown to each respondent for surveying the preference and emotion by SD (semantic differential) scale. It was statically significant that the filler plant group was the least preferred one between the indoor foliage plant and the preference of line plant group was the highest. In filler plant Scindapsus aureus is significantly favored, in mass plant Aglaonema crispum and Syngonium podophyllum, in form plant Ficus banghalensis in line plant Dracaena fragrans ‘Lemon Lime’, respectively. The green is the most preferred color of leaf and gray is the least one. When investigated on the major emotions felt with four types of indoor foliage plant with SD scale, filler plant felt as ‘Bright’, ‘Light’, ‘Pale’, mass plant ‘Warm’, ‘Sharp’, form plant ‘Simple’, ‘Luxurious’ and line plant ‘Sophisticated’, ‘Luxurious’, ‘Pleasant’, ‘Soft’ and ‘Fancy’, respectively. This result will be valuable when the indoor garden is designed with an indoor foliage plant.

White light and compound light were found to be the ideal light sources for improving the functionality and ornamental value of indoor plants and reducing the cost of maintenance, but because compound light hinders people from recognizing the original color of plants and makes their eyes easily tired, white light was considered the optimal light satisfying all of the ornamental value, economic efficiency and functionality resulting from plant growth. On the other hand, in the results of examining physiological changes before and after treatment on fine dust PM10 and carbon dioxide removal capacity in a closed chamber under an artificial light source, the patterns of carbon dioxide and fine dust removal were similar among the treatment groups according to light condition, but according to plant type, the removal rate per unit leaf area was highest in Spathiphyllum and lowest in Dieffenbachia. In the experiment on dust and carbon dioxide removal, the photosynthetic rate was over 2 times higher after the treatment, and the rate increased particularly markedly under compound light and white light, suggesting that the photosynthetic rate of plants increases differently according to light quality. These results show that light quality has a significant effect on the photosynthetic rate of plants, and suggests that plants with a high photosynthetic rate also have a high carbon dioxide and dust removal capacity. In conclusion, the photosynthetic rate of foliage plants increased under white and blue light that affect photosynthesis and the increased photosynthetic rate reduced carbon dioxide and fine dust, and therefore white and compound light were found to be the optimal light sources most functional and economically efficient in improving ornamental value and indoor air quality.