• Polymer(Korea)
• /
• v.24 no.1
• /
• pp.97-104
• /
• 2000

PAN-based activated carbon fibers/phenolic resin matrix composites (ACFCs) were manufactured via molding process with oxidized carbon fabrics (plain-type) and phenolic resin (resole-type) compounded by 70 : 30 wt%. The green body (as molded) was submitted to carbonization (at 100$0^{\circ}C$) in an inert environment and activation (at 700, 800, 900 and 100$0^{\circ}C$) in a $CO_2$ environment. In this work, the influence of activation temperatures was investigated in surface properties, such as pH, acid- and base-values by titration method, and in adsorption properties, i.e., specific surface area and pore structures by BET-method of the composites. Also, the pressure drops of the specimens were calibrated by ASTM. As a result, the activation temperature influenced the surface property of ACFCs. When the activation temperature was higher than 90$0^{\circ}C$, the surface was gradually developed in basic nature. And, the evolutions of specific surface area, total pore volume and pore size distribution of ACFCs could be easily confirmed the dependence on the activation temperature. Among them, well-developed pore structure from adsorption characteristics was changed of the ACFCs activated at 90$0^{\circ}C$. Also, the pressure drop was slightly decreased with increasing the temperature due to increasing the burn-off with heat treatment temperature of ACFCs.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.12
• /
• pp.264-275
• /
• 2017

Objective: This study examines the effects of children's art activities through forest experience in relation with Nuri curriculum on environmental sensitivity. Method: A survey was administered to an experimental group of 20 children as well as a control group of 20 children for statistical analysis. after 16-class art activities through forest experience were performed to children aged 4 at a daycare center for 50 days. Result: Children's art activities through forest experience in relation with Nuri curriculum had a positive effect on their environmental sensitivity. In particular, their art activities had a positive effect on their self-awareness, self-regulation, empathy and motivation in the experimental group, supporting the educational effects and benefits of developmental children's art activities through forest experience in relation with Nuri curriculum. In other words, art activities through forest experience are useful in terms of providing children with creative expression activities in art by leading to observation and exploration, as well as educational experiences that have positive attitudes toward the environment. Conclusion: As children's art activities through forest experience have a positive effect on their environmental sensitivity, more useful information on teaching-learning methods will be able to be provided to early childhood teachers in the field. Consequently, children's art activities through forest experience need to be actively introduced in the field of early childhood education as an alternative for learning nature and improving environment-friendly emotional intelligence.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.11 no.2
• /
• pp.66-73
• /
• 2003

To investigate the availability of solidified wastes as resource, wastewater sludge, waste gypsum and fly ash were mixed and the results with various mixing ratios are as follows. Compressive strength turned out to be increasing as the amount of waste gypsum increases, keeps longer curing inhibition, and higher forming Pressure under the conditions of waste gypsum/sludge ratio 0.31-0.45, and 0.9kg cement as 15% and 1.2kg cement as 20% of total amount. Solidified agent under the fly ash/sludge ratio 0.45, 0.6, compressive strength seemed to be higher than standard one which means solidified wastes with these conditions could be applicable in real life. These results inform that concentrations of the leachate $Cr^{+6}$, Cu, Zn, Cd, Pb solidified matrix, containing low concentration of heavy metal, were cured with/without enough time it still will cause adverse effect on nature environment and application of heavy metal sequester must be needed to reuse industrial wastes from incineration plant solidified matrix. Total cost price, when considering manufacturing capability of the facilities for resourcerizing as 18,000ton was presented 678,664,000 won, as it were, manufacturing cost price was 37,704 won per ton. The results as above has shown that it's possible to use the mixture of waste gypsum/sludge, fly ash/sludge, cement, additions, and solidification matter as substitute of materials like brick, block, interlocking which has proper compressive strength of KS L 5201 and KS F 4004.

• Journal of Soil and Groundwater Environment
• /
• v.9 no.1
• /
• pp.70-78
• /
• 2004

The current study was undertaken to evaluate the hydrogeochemical implications of heavy metals (Cr, Cu, Pb, Zn) in both soils and groundwater in reclaimed lands of Sydney's 2000 Olympic Games site at Homebush Bay in Port Jackson, Sydney. The Olympic Games site can be divided into three areas, i.e. 'reclaimed areas' were previously estuarine, and were filled with waste materials and are now above present high tide level, whereas 'landfill areas' are areas where deposition of waste materials occurred above sea level. No deposition of waste took place in 'non-infilled areas'. 4513 soil core samples and 101 groundwater samples were analyzed for Cr, Cu, Pb, Zn. The mean heavy metal (Cr, Cu, Pb, Zn) concentrations in soils of the study area revealed the order of reclaimed (greatest), landfill and non-infilled area (smallest), whereas in groundwater it is all shown the order of landfill, reclaimed and non-infilled area, except for Pb. Mean Pb concentration in soils derived from the three land types at the Olympic Games site revealed the order of reclaimed area(174 $\mu\textrm{g}$/g), landfill area (102 $\mu\textrm{g}$/g) and non-infilled area (48 $\mu\textrm{g}$/g). Results reveal that soils contaminated by Cr, Cu, Pb and Zn in reclaimed/landfill areas are associated with dumped materials. No relationship could be established between soil and groundwater concentrations of heavy metals (Cr, Cu, Pb, Zn) in the landfill, reclaimed and non-infilled areas of the Olympic site, probably due to the varied nature of the materials deposited at the Olympic site.

• Journal of Plant Biotechnology
• /
• v.39 no.3
• /
• pp.163-168
• /
• 2012

An optimization in vitro seed germination was established by using triphenol tetrazolium chloride (TTC) test, which has been known as two rare orchids (Gastrodia verrucosa Blume and Hetaeria sikokiana Tuyama) in Jeju island. We have established proper NaOCl treatment for in vitro germination of G. verrucosa and H. sikokiana through TTC test. In the case of H. sikokiana, seed viability through TTC test was high with 95% in control. However, NaOCl 1% treatment for 30 minutes showed the highest embryo swelling rate to seed viability. Likewise, swelling formation of embryos, diameter of embryos, protocorm formation and diameter of protocorms of G. verrucosa was 87%, $59{\mu}m$, 91% and $138{\mu}m$ through NaOCl 1% treatment for 30 minutes. This result will be applied on the basic information for improving in vitro seed germination rate of G. verrucosa and H. sikokiana.

• The Journal of Engineering Geology
• /
• v.22 no.2
• /
• pp.173-183
• /
• 2012

The nature of surface deformation of Tono granite was investigated using a confocal laser scanning microscope (CLSM) under water-saturated stress relaxation conditions. A new apparatus was developed for this experiment, enabling continuous measurements of stress-strain and simultaneous observations of surface deformation by CLSM. The amounts of grain contact deformation and intra-granular surface deformation were calculated using a finite element method. The results reveal that intense grain contact deformation and intra-granular surface deformation occurred during the period of stress relaxation, and that the intensity of this deformation increased with increasing applied stress. Finite element method (FEM) results show that the strain of grain boundary was greater than strain of inter-granular surface. Contour maps of these local strains were compiled for individual grains and their boundaries, revealing intense deformation at the boundaries between biotite and quartz under compressional stress. This result was a consequence of the mechano-chemical effect of biotite and quartz minerals. Biotite in granite has a layered structure of iron-magnesium-aluminum silicate sheets that are weakly bonded together by layers of potassium ions. In contrast, quartz occurs as stable spherical grains.

• Korean Journal of Ecology and Environment
• /
• v.39 no.4 s.118
• /
• pp.489-497
• /
• 2006

The feasibility of the Natural and Ecological Wastewater treatment System (NEWS) was examined for rural wastewater treatment in Korea. The intermittent trickling biofilter with high hydrophilic filter media was used for pretreatment for suspended solids and organic pollutants. The subsequent constructed wetland with porous granule materials was used for promoting nutrient removal. The results show that the removal efficiencies of the system were high with respect to the water quality parameters except COD. Even if the effluent from the biofilter did not meet the guidelines for wastewater treatment plant effluent in Korea in terms of $BOD_5$ and TN, the final effluent of the system meets the guidelines us to good performance of the constructed wetland. The regression analysis between pollutant loading rate and removal rate indicated that the system could have stable removal for SS, $BOD_5$, TN, and TP in the given influent ranges. The analysis in the winter period indicated that the wetland covered with transparent polycarbonate glass had the statble performance during the winter period dus to increase of temperature inside the wetland without any heating system. With the stable performance, effective poilutant removal, low maintenance, and cost-effectiveness, the NEWS could be considered as an alternative treatment system for decentralized regions and rural communities in Korea.

• Journal of the Korean institute of surface engineering
• /
• v.12 no.3
• /
• pp.207-216
• /
• 1979

Environmental pollution or contaminations caused by various kinds of pollutants have become one of most serious problems of our time. Environ mental pollution is the unfavoralble alteration of our surroundings, through direct or indirect effects of changes in energy patterns, rediation levels, chemical and physical constitution and abundances of organisms. These changes may affect humans directly or through their supplies of water and of agicultural and other biological products, their physical objects or possessions, or their opportunities for recreation and appreciation of nature. Pollutants that meet the criteria of this definition of environmental pollution are numerous: gases (such as sulfur dioxide and nitrogen oxides) and paniculate matter (such as smoke particles, lead aerosols, and asbestos) in the atmosphere; pesticides and radioactive isotopes in the atmosphee and in waterways; sewage, organic. chemicals, and phosphates in water; solid wastes on land; excessive heating (thermal pollution) of rivers and lakes; and many others. Some of these pollutants are introduced into the environment naturally, others by human actions, and most in both ways. Our major concer is with environmental pollution resulting wholly or largely as a by-product of human activities, because these can be controlled most readily. Environmental pollution cannot be solved by science and technology alone. It should be handled by an interdisciplinary approach with combined methods of science and technology as wen as social science disciplines for the better solution of this critical problem. In this respect, introducing "Environmental Science," a new scientific approach for the solution of environmental problems, which is now widely accepted by most developed countries of the world will be very helpful for systematization of theoretical basis for a new scientific approach to environmental pollution. Environmental science is "the study of all systems of air, land, water, energy, and life that surround Man. It includes all sciences directed to the system-level of understanding of the environment, drawing especially upon such disciplines as meteorology, geophysics, oceanography, and ecology, and utilizing to the fullest knowledge and techniques developed in such fields as physics, chemistry, biology, mathematics and engineering as well as many social science disciplines, such as economics, such as economics, law, political science and public administration." The components of this discipline are not new, for they are drawn from existing areas of science within biology chemistry, physics, and geoscience. What is really new about environmental science, however, is it siewpoint - its orientation to global problems, its conception of the earth as a set of interlocking, interacting systems, and its interest in Man as a part of these systems.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.6
• /
• pp.117-125
• /
• 2008

The Object tracking by real-time image analysis is one of the major concerns in computer vision and its application fields. The Object detection process of real-time images must be preceded before the object tracking process. To achieve the stable object detection performance in the exterior environment, adaptive background model generation methods are needed. The adaptive background model can accept the nature's phenomena changes and adapt the system to the changes such as light or shadow movements that are caused by changes of meridian altitudes of the sun. In this paper, we propose a robust background model generation method effective in an illegal parking auto-detection application area. We also provide a evaluation method that judges whether a moving vehicle stops or not. As the first step, an initial background model is generated. Then the differences between the initial model and the input image frame is used to trace the movement of object. The moving vehicle can be easily recognized from the object tracking process. After that, the model is updated by the background information except the moving object. These steps are repeated. The experiment results show that our background model is effective and adaptable in the variable exterior environment. The results also show our model can detect objects moving slowly. This paper includes the performance evaluation results of the proposed method on the real roads.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.5
• /
• pp.519-526
• /
• 2018

In this study, an algorithm to predict evacuation routes in support of shipboard lifesaving activities is presented. As the first step of algorithm development, the feasibility and necessity of an evacuation route prediction algorithm are shown numerically. The proposed algorithm can be explained in brief as follows. This system continuously obtains and analyzes passenger movement data from the ship's monitoring system during non-disaster conditions. In case of a disaster, evacuation route prediction information is derived using the previously acquired data and a prediction tool, with the results provided to rescuers to minimize casualties. In this study, evacuation-related data obtained through fire evacuation trials was filtered and analyzed using a statistical method. In a simulation using the conventional evacuation prediction tool, it was found that reliable prediction results were obtained only in the SN1 trial because of the conceptual and structural nature of the tool itself. In order to verify the validity of the algorithm proposed in this study, an industrial engineering tool was adapted for evacuation characteristics prediction. When the proposed algorithm was implemented, the predicted values for average evacuation time and route were very similar to the measured values with error ranges of 0.6-6.9 % and 0.6-3.6 %, respectively. In the future, development of a high-performance evacuation route prediction algorithm is planned based on shipboard data monitoring and analysis.