• Environmental Engineering Research
• /
• v.18 no.2
• /
• pp.85-90
• /
• 2013

This study is an attempt to quantify rainwater utilization and miscellaneous water demand in Tokyo's 23 special wards, the core of the urban area in Tokyo, Japan, in order to elucidate the potential of further rainwater utilization. The rainwater utilization for miscellaneous appropriate water demands, including toilet flushing, air conditioning, and garden irrigation, were calculated for six different types of building: residential house, office, department store, supermarket, restaurant, and accommodation. Miscellaneous water demands in these different types of building were expressed in terms of equivalent rainfall of 767, 1,133, 3,318, 1,887, 16,574, and 2,227 (mm/yr), respectively, compared with 1,528 mm of Tokyo's average annual precipitation. Building types, numbers and its height were considered in this study area using geographic information system data to quantify miscellaneous water demands and the amount of rainwater utilization in each ward. Area precipitation-demand ratio was used to measure rainwater utilization potential for miscellaneous water demands. Office and commercial areas, such as Chiyoda ward, showed rainwater utilization potentials of <0.3, which was relatively low compared to those wards where many residential houses are located. This is attributed to the relatively high miscellaneous water demand. In light of rainwater utilization based on building level, the introduction of rainwater storage mechanisms with a storage depth of 50 mm for six different types of buildings was considered, and calculated as rainfall of 573, 679, 819, 766, 930, and 787 (mm), respectively. Total rainwater utilization using such storage facilities in each building from 23 wards resulted in the retention of 102,760,000 $m^3$ of water for use in miscellaneous applications annually, and this volume corresponded to 26.3% of annual miscellaneous water demand.

• Korean journal of applied entomology
• /
• v.46 no.3
• /
• pp.335-341
• /
• 2007

The main habitats of diving beetles in agricultural ecosystems were identified as ponds, irrigation channels, and reservoirs, where the water system is maintained throughout the year. Four species, Cybister japonicus, Cybister brevis, Hyphydrus japonicus and Noterus angustulus, were selected as biological indicators which can be used to evaluate the healthiness of the agricultural ecosystem. The species number of 4 indicator species, the species number of diving beetle species, and the diversity index were used as factors for environmental evaluation. The evaluation was classified into grades $I{\sim}IV$. The non-fertilizer and non-pesticide agricultural practicing area and the sustainable agricultural practicing area were evaluated as grades $I{\sim}II$, and the general agricultural area to be relatively fine with a grade II. However, the analysis indicated the agricultural areas near a residential area and an industrial complex to be poor with a grade of IV, suggesting that immediate improvement in the agricultural environment is needed.

• YAKHAK HOEJI
• /
• v.51 no.6
• /
• pp.415-423
• /
• 2007

This study was to evaluate the genotoxic effects of airborne particulate matters using single cell gell elec trophoresis (comet assay) in A549 human lung carcinoma cells. The total suspended particulate (TSP) was collected on back-up filter in Chuncheon, Kangwon Do, South Korea from April, 2003 to February, 2005. The concentrations of TSP, B(a)p and most of heavy metals seemed to be higher in spring and winter, and lower in summer. And they showed higher concentration in the commercial areas and the residential area having more traffics than in the rural area. It was found that A549 cells interacting with the organic extract of TSP showed more DNA single-strand breaks compare to untreated cells. The genotoxicity of the organic extract of TSP was increased with the pre-treatment of S-9 mixture during the culture or with the treatment of endonuclease after cell lysis. The DNA damage by the organic extract of TSP was higher in winter and the commercial area than in summer and the rural area. This study suggests that TSP, heavy metals and B(a)P analyzed showed significant variation depend on the seasons and the areas which are correlated with the DNA damage evaluated by Comet assay, indicating that genotoxic biomarker is useful for toxicological evaluation of air quality.

• Journal of Environmental Health Sciences
• /
• v.47 no.4
• /
• pp.330-338
• /
• 2021

Background: This study was conducted to provide background information for the proper management of radon contamination in apartments using mechanical ventilation facilities in residential environments. Objectives: To this end, this study compared and evaluated changes in radon concentrations based on different operating intensities of mechanical ventilation with or without natural ventilation. Methods: For the continuous measurement of radon concentrations, an RAD7 instrument was installed in four apartments equipped with a ventilation system. The measurements were done for comparison of ventilation types and different ventilation intensities ("high", "middle", "low"). Results: The results confirmed that both mechanical and natural ventilation sufficiently reduced the radon concentration in the apartments. In particular, mechanical ventilation at "high" intensity was the most effective. Natural ventilation combined with mechanical ventilation and then natural ventilation alone were the second and the third most effective, respectively. Conclusions: When using ventilation to reduce indoor radon concentrations, it is most effective to operate mechanical ventilation ("high") or natural ventilation and mechanical ventilation at the same time. In cases where mechanical ventilation is available alone, it is recommended to operate it at a minimum of "middle" intensity.

• KIEAE Journal
• /
• v.14 no.2
• /
• pp.77-86
• /
• 2014

Plenty of efforts have been made in the traditional architecture of Korea, Hanok, to develop various elements such as restoration, the introduction of new design, and energy-saving while systemic setups on standard and evaluation of eco-friendly energy design of Hanok are lacking. If we evaluate energy performance based on current standards without reflecting unique features of Hanok on the system, Hanok will be included in the very low grade among the residential buildings being included in the approval system of eco-friendly architecture or the unique features will be modified and the burden of increased construction cost. Therefore, this study is to prepare the basic reference for the introductory evaluation system by evaluating the energy performance level of NEO-Hanok based on the current building energy rating system. The result for NEO-Hanok based on the building energy rating system, we propose the rating standard with scorecard elements of NEO-Hanok by considering the necessity of identity and standard for NEO-Hanok. As a result of infiltration test to check the tightness, it was measured as 10.81 times/h (50 ACH). As we switch from the main insulation for the wall from the glass wool 64k(0.035W/mk) to rigid polyurethane foam first class first unit (0.024W/mk), the result was slightly increased from the first demand quantity rating yield $249.8kWh/m^2{\cdot}yr$ to $235.0kWh/m^2{\cdot}yr$. Current certificate system is focused more on the heating load than the cooling load, it is disadvantageous for Hanok, which has less cooling energy consumption in summer. The rating result from the target building study is level 4.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.28 no.2
• /
• pp.513-528
• /
• 2018

In a smart home environment that integrates IoT technology into a residential environment, the smart home hub provides convenience functions to users by connecting various IoT devices to the network. The smart home hub plays a role as a gateway to and from various data in the process of connecting and using IoT devices. This data can be abused as personal information because it is closely related to the living environment of the user. Such abuse of personal information may cause damage such as exposure of the user's identity. Therefore, this thesis analyzed the threat by using LINDDUN, which is a threat modeling technique for personal information protection which was not used in domestic for Smart Home Hub. We present evaluation criteria for smart home hubs using the Common Criteria, which is an international standard, against threats analyzed and corresponding security requirements.

• The Journal of the Korea Contents Association
• /
• v.18 no.4
• /
• pp.688-697
• /
• 2018

The following research was conducted to encourage residents in urban areas to move to rural areas, and to improve the residential environments in those rural areas. Current policies for rural village development Project were analyzed, and policy implications were proposed. Residents in rural villages participated in a 12-question survey that asked their priorities prior to moving to the area, and factors contributing to resident satisfaction. Importance and Performance Analysis (IPA) was performed to present potential development strategies in the construction business. As a result, 'natural environment and landscapes' had the highest priority and satisfaction, whereas 'lack of public transportation and accessibility' and 'road conditions and parking facilities' had high priorities but low satisfaction levels. Thus, it is important to take nature and environment, as well as accessibility into consideration when moving to rural villages. Although this research was based on residents' bias, and the sample area was limited, these conclusions still offer important policy agreement provide of future rural villages location selection and establishment of land use planning.

• Toxicological Research
• /
• v.13 no.1_2
• /
• pp.49-54
• /
• 1997

PCBs are classified as B2 (Probable human carcinogen) based on the induction of hepatocellular carcinomas in rats and mice from IRIS (Integrated Risk Information System). About 20 years ago, PCBs were phased out for electrical use in Korea, but PCBs were continuously used in the other field. Lately, there has been increasing concern on possible effects of contaminated soil to the other environment and human health. The purpose of this study is to determine PCBs level in soil at some site and to assess the human exposure doses according to exposure routes for people living within sites which expected to be exposed to PCBs. Pollution level of PCBs on the site was monitored using gas liquid chromatography. To assess the transport of PCBs in soil to plant and to air, various transfer factors(diffusion coefficient, bioconcentration factor etc.) were considered in simple calculations. To calculate the residential exposure doses by routes, some equations were considered using assumption value, which define inhalation, ingestion (soil, plant) and derreal uptake pathway. Computated results will be used as risk assessment information for human health evaluation on contaminated soil.

• Journal of Institute of Control, Robotics and Systems
• /
• v.20 no.12
• /
• pp.1181-1188
• /
• 2014

In this paper, we propose a novel concept foran unmanned delivery service using a cooperative heterogeneous unmanned system consisting of a self-driving car and an unmanned aerial vehicle (UAV). The proposed concept is suitable to deliver parcels in high-density and high-rise urban or residential areas. In order to achieve the proposed concept, we will develop acooperative heterogeneous unmanned system. Customers can order goods using a smartphone application and the order information, including the position of the customer and the order time, and the package is transported automatically by the unmanned systems. The system assigns the tasks suitable for each unmanned vehicle by analyzing it based on map information. Performance is validated by experiments consisting of autonomous driving and flight tests in a real environment. For more evaluation, the landing position error analysis is performed using circular error probability (CEP).

• KIEAE Journal
• /
• v.10 no.4
• /
• pp.59-66
• /
• 2010

Natural ventilation is major strategy of 'sustainable building'. It aims to supply fresh air to the indoor, and to remove heat from the indoor during summer. In the latter point of view, natural ventilation can be grouped into two main strategies, daytime ventilation and night cooing. If we take advantage of these two natural ventilation strategies, indoor thermal comfort can be significantly improved. This study focused on grasping the current situation and problem of indoor thermal comfort of the naturally ventilated residential buildings to seek for direction of later studies. Additionally, thermal comfort of residence where the interior blind and exterior insulation were applied was analyzed. It was analyzed that the percentage of the time which satisfy the indoor acceptable operative temperature during summer was 90 ~ 95% and the heat control performance of natural ventilation has a limitation. When the interior blind and exterior insulation were applied, indoor thermal comfort was significantly improved. However, it still need more improvement.