• Journal of the Korean earth science society
• /
• v.29 no.2
• /
• pp.189-203
• /
• 2008

Microcomputer Based Laboratory (MBL), by offering accurate and effective data collection and real-time graphs, enables students to reduce experiment time and, thereby, have deeper discussions concerning experimental results. This helps to emphasis the essential aspect of scientific inquiry; the process communication. Therefore, this study examined secondary school earth science MBL lessons with regards to the five basic aspects of scientific inquiry: "Asking", "Evidencing", "Explaining", "Evaluating" and "Communicating". It then investigated the level of argumentative communication between the students and teachers and also among the students themselves. For this study, three classroom activities were observed and videotaped, and teaching materials, textbooks and students' notes were collected. The transcribed data were analyzed from the perspective of scientific inquiry level and argument frames. The results showed that the scientific inquiry levels of the three classes were similar, except for the "Communicating" aspect, which appeared in only one episode. "Asking" was carried out by the teacher and then students were directed to collect certain data in the "Evidencing" stage. Furthermore, students were given possible ways to use evidence to formulate explanations and connections through the "Explaining" and "Evaluating" stages. In the argumentation analysis, most argumentative communication was identified as being associated with a given procedure, rather than with any scientific phenomena. In only one episode, did "Communicating" relate directly to any scientific phenomena. It can be concluded, that although MEL places emphasis on communication for authentic scientific inquiry, the environment required for such inquiry and argumentative communication can not be easily created in the classroom. Therefore, in order for authentic inquiry to take place in the MBL classroom, teachers should provide students with the opportunity to develop meaningful argumentation and scaffolding abilities.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.2
• /
• pp.156-162
• /
• 2008

Salmonellosis is a major bacterial zoonosis that causes a variety of disease syndromes, self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Recently, the emergence of multidrug resistant strains of Salmonella spp. causes more serious problems in environment and public health. The present study was investigated the antibacterial effect of Houttuynia cordata ethanol extract(HCEE) for murine salmonellosis. In the cytotoxic effect of HCEE on RAW 264.7 cells, there was no detectable effect with any concentrations between 25 and 100 ${\mu}g/ml$ after 8 h incubation. The bacteriocidal effect of HCEE was not showed on a Salmonella enterica serovar Typhimurium(S. typhimurium). HCEE makes morphological change of the RAW 264.7 cells, and there was significant decreased bacterial uptake and intracellular replication within Salmonella infected cells. And further nitric oxide(NO) production of Salmonella infected RAW 264.7 cells with HCEE was decreased comparing to RAW 264.7 cells without HCEE until 8 h post infection. Oral administration of HCEE showed a therapeutic effect for S. typhimurium infected BALB/c mice. The mortality of HCEE treated mouse was 80% until 12 days, while that of HCEE untreated mouse was 100 % until 8 days after lethal dose of S. typhimurium infection. These data suggested that HCEE has a potency treatment for intracellular replicative pathogen including salmonellosis, brucellosis, tuberculosis, listeriosis etc., and the application of HCEE makes new strategies for safety medicine development without antibiotic resistance bacterial appearance and residue problem in food and solves the public health problem from antibiotic mis- and over use.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.2
• /
• pp.120-132
• /
• 2008

Remotely sensed images from a satellite can be applied for detecting and quantifying spatial and temporal variations in terms of landuse & landcover, crop growth, and disaster for agricultural applications. The purposes of this study were to analyze topography using DEM(digital elevation model) and classify landuse & landcover into 10 classes-paddy field, dry field, forest, bare land, grass & bush, water body, reclaimed land, salt farm, residence & building, and others-using Landsat TM images in North Korea. Elevation was greater than 1,000 meters in the eastern part of North Korea around Ranggang-do where Kaemagowon was located. Pyeongnam and Hwangnam in the western part of North Korea were low in elevation. Topography of North Korea showed typical 'east-high and west-low' landform characteristics. Landcover classification of North Korea using spectral reflectance of multi-temporal Landsat TM images was performed and the statistics of each landcover by administrative district, slope, and agroclimatic zone were calculated in terms of area. Forest areas accounted for 69.6 percent of the whole area while the areas of dry fields and paddy fields were 15.7 percent and 4.2 percent, respectively. Bare land and water body occupied 6.6 percent and 1.6 percent, respectively. Residence & building reached less than 1 percent of the country. Paddy field areas concentrated in the A slope ranged from 0 to 2 percent(greater than 80 percent). The dry field areas were shown in the A slope the most, followed by D, E, C, B, and F slopes. According to the statistics by agroclimatic zone, paddy and dry fields were mainly distributed in the North plain region(N-6) and North western coastal region(N-7). Forest areas were evenly distributed all over the agroclimatic regions. Periodic landcover analysis of North Korea based on remote sensing technique using satellite imagery can produce spatial and temporal statistics information for future landuse management and planning of North Korea.

• Korean Chemical Engineering Research
• /
• v.53 no.5
• /
• pp.557-564
• /
• 2015

The previous etching, rinsing and drying processes of wafers for MEMS (microelectromechanical system) using SC-$CO_2$ (supercritical-$CO_2$) consists of two steps. Firstly, MEMS-wafers are etched by organic solvent in a separate etching equipment from the high pressure dryer and then moved to the high pressure dryer to rinse and dry them using SC-$CO_2$. We found that the previous two step process could be applied to etch and dry wafers for MEMS but could not confirm the reproducibility through several experiments. We thought the cause of that was the stiction of structures occurring due to vaporization of the etching solvent during moving MEMS wafer to high pressure dryer after etching it outside. In order to improve the structure stiction problem, we designed a continuous process for etching, rinsing and drying MEMS-wafers using SC-$CO_2$ without moving them. And we also wanted to know relations of states of carbon dioxide (gas, liquid, supercritical fluid) to the structure stiction problem. In the case of using gas carbon dioxide (3 MPa, $25^{\circ}C$) as an etching solvent, we could obtain well-treated MEMS-wafers without stiction and confirm the reproducibility of experimental results. The quantity of rinsing solvent used could be also reduced compared with the previous technology. In the case of using liquid carbon dioxide (3 MPa, $5^{\circ}C$, we could not obtain well-treated MEMS-wafers without stiction due to the phase separation of between liquid carbon dioxide and etching co-solvent(acetone). In the case of using SC-$CO_2$ (7.5 Mpa, $40^{\circ}C$), we had as good results as those of the case using gas-$CO_2$. Besides the processing time was shortened compared with that of the case of using gas-$CO_2$.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.13 no.4
• /
• pp.111-124
• /
• 2010

To monitor the environment of land surface change is considered as an important research field since those parameters are related with land use, climate change, meteorological study, agriculture modulation, surface energy balance, and surface environment system. For the change detection, many different methods have been presented for distributing more detailed information with various tools from ground based measurement to satellite multi-spectral sensor. Recently, using high resolution satellite data is considered the most efficient way to monitor extensive land environmental system especially for higher spatial and temporal resolution. In this study, we use two different spatial resolution satellites; the one is SPOT/VEGETATION with 1 km spatial resolution to detect coarse resolution of the area change and determine objective threshold. The other is Landsat satellite having high resolution to figure out detailed land environmental change. According to their spatial resolution, they show different observation characteristics such as repeat cycle, and the global coverage. By correlating two kinds of satellites, we can detect land surface change from mid resolution to high resolution. The K-mean clustering algorithm is applied to detect changed area with two different temporal images. When using solar spectral band, there are complicate surface reflectance scattering characteristics which make surface change detection difficult. That effect would be leading serious problems when interpreting surface characteristics. For example, in spite of constant their own surface reflectance value, it could be changed according to solar, and sensor relative observation location. To reduce those affects, in this study, long-term Normalized Difference Vegetation Index (NDVI) with solar spectral channels performed for atmospheric and bi-directional correction from SPOT/VEGETATION data are utilized to offer objective threshold value for detecting land surface change, since that NDVI has less sensitivity for solar geometry than solar channel. The surface change detection based on long-term NDVI shows improved results than when only using Landsat.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.20 no.3
• /
• pp.263-268
• /
• 1998

Many myocutaneous flaps have been used for the reconstruction of intraoral defects caused by the excision of oral cancer. Among these myocutaneous flaps, cervical island flap has been introduced by Farr et al. Although different in detail, this flap was designed as the platysma myocutaneous flap by Futrell et al in the supraclavicular site. Since many authors applied this flap to cover intraoral defect, they discussed deeply the blood supply of this flap. To improve further flap survival, it was modified by Tashiro et al. This flap makes its vascularity highly reliable. The amount of tissue needed for reconstruction can be accurately planned. The surgical and reconstruction procedure can be performed simply, rapidly, and effectively. Oral functions including deglutition, speech, and denture fitting are not compromised. With it's minimal deformity, new donor fields is not necessory. Of course, we keep in mind that this flap has limitations in patients where much bulk of tissue defects is needed and more than 3000 rad radiation due to the metastasis of neck lymph node is exposed. In three patients with intraoral squamous cell carcinoma($T_{1-3}N_0M_0$), we performed induction chemotherapy with FP regimen including pepleomycin. Thereafter, we ablated oral cancer and peformed reconstruction of intraoral defects with cervical island flap designed by Tashiro et al. Due to these significant benefits and minimal limitations, we have found that this flap is adequate for reconstruction of most intraoral defects following cancer ablation.

• The korean journal of orthodontics
• /
• v.27 no.5 s.64
• /
• pp.815-824
• /
• 1997

The purpose of this study is to develop the basic algorithm for the finite element method modeling of individual malocclusions. Usually, a great deal of time is spent in preprocessing. To reduce the time required, we developed a standardized procedure for measuring the position of each tooth and a program to automatically preprocess. The following procedures were carried to complete this study. 1. Twenty-eight teeth morphologies were constructed three-dimensionally for the finite element analysis and saved as separate files. 2. Standard brackets were attached so that the FA points coincide with the center of the brackets. 3. The study model of a patient was made. 4. Using the study model, the crown inclination, angulation, and the vertical distance from the tip of a tooth was measured by using specially designed tools. 5. The arch form was determined from a picture of the model with an image processing technique. 6. The measured data were input as a rotational matrix. 7. The program provides an output file containing the necessary information about the three-dimensional position of teeth, which is applicable to several finite element programs commonly used. The program for a basic algorithm was made with Turbo-C and the subsequent outfile was applied to ANSYS. This standardized model measuring procedure and the program reduce the time required, especially for preprocessing and can be applied to other malocclusions easily.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.6
• /
• pp.588-597
• /
• 2016

In this study, we attempted to improve the biogas production efficiency by varying the mixing ratio of the mixed sludge of organic wastes in the improved single-phase anaerobic digestion process. The types of organic waste used in this study were raw sewage sludge, food wastewater leachate and livestock excretions. The biomethane potential was determined through the BMP test. The results showed that the biomethane potential of the livestock excretions was the highest at $1.55m^3CN4/kgVS$, and that the highest value of the composite sample, containing primary sludge, food waste leachate and livestock excretions at proportions of 50%, 30% and 20% respectively) was $0.43m^3CN4/kgVS$. On the other hand, the optimal mixture ratio of composite sludge in the demonstration plant was 68.5 (raw sludge) : 18.0 (food waste leachate) : 13.5 (livestock excretions), which was a somewhat different result from that obtained in the BMP test. This difference was attributed to the changes in the composite sludge properties and digester operating conditions, such as the retention time. The amount of biogas produced in the single-phase anaerobic digestion process was $2,514m^3/d$ with a methane content of 62.8%. Considering the value of $2,319m^3/d$ of biogas produced as its design capacity, it was considered that this process demonstrated the maximum capacity. Also, through this study, it was shown that, in the case of the anaerobic digestion process, the two-phase digestion process is better in terms of its stable tank operation and high efficiency, whereas the existing single-phase digestion process allows for the improvement of the digestion efficiency and performance.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.44 no.1
• /
• pp.107-118
• /
• 2016

The Seoul metropolitan government announced an open design competition for reconfiguring the annex building of the National Tax Service Building site on Sejong-daero as a space for citizens to commemorate the 70th anniversary of Korea's liberation. The site, built during the Japanese colonial period, has been in use ever since. This study, as one of the entries for the competition, described the strategy and design contents by drawing the concept and main points of the design through an analysis of the historical context of the site. As the guidelines instructed to consider the value of the Sejong-daero area and the cultural heritage through a comprehensive analysis, this study specified the site as a place connecting the past, present and future. Since the foundation of the Joseon dynasty, the Korean Empire and the Japanese colonial period, Sejong-daero has been a main site for important events and activities along with the change of the city structure. Jungdong, to the rear of the site, was a place for adopting new culture during the beginnings of modern Korea, while adjacent places like Duksugung, the Anglican church, and the Seoul City Council building have also been historic urban landscapes of the historical layers of time as the city has changed. When Gojong announced the Korean Empire, the city structure was remodeled with this site as the center along with Sogong-ro, Wongudan and so forth. In this study, public interest stated in the guidelines was focused and the relevance of the road and the plaza was considered from the view of an historic urban landscape by a comprehensive analysis with Sejong-daero as the center. The restoration of public interest was to be drawn as the concept of the object site by considering the current status and the change around the site and Jungdong at the rear. Returning the site to the public is ambiguous with the relevance of the restoration of public interest and as the symbol of the idea of the Korean Empire by Gojong's announcement. The object site, having the characteristic of being returned to the public, must ensure public interest and therefore the design strategy has been established with the keywords of openness, connection and void. As a result of a review of the alternatives, a plan for a square has an 8% slope, just as the original site does, and provides ramps for convenient access for all, including the disabled and the elderly, and is connected to the grounds adjacent. No construction is allowed at the terrace square of the Anglican church level and the main square connected to the pedestrian street, so a variety of modern city utilization can be done. The value of the site at which this design is aimed shall be given back to the public with the concepts of modern democracy, independence, and the vision of Gojong by reinterpreting the space from a modern viewpoint. This study focused on the processes of establishing a main concept and strategy rather than the content of the design details, and the suggestion is meaningful in that the design for the object site with historic backgrounds and the layers of time can continue to be grown.

• Archives of design research
• /
• v.20 no.3 s.71
• /
• pp.299-314
• /
• 2007

For the past 20 years, the growth and development of university-design-educational institutes contributed to the industrial development of our country. Due to the technological fluctuation and changes in the industrial structure in the latter half of the 20th century, the enterprise is demanding professionally-oriented design manpower. The principle which appears from instances of the advanced nations is to accommodate the demands in social changes and apply them to educational design programs. In order to respond promptly to the industrial demand especially, the advanced nations adopted "multidisciplinary design education programs" to lead innovation in the area of design globally. The objective of the research consequently is to suggest an educational system and a program through which the designer can be educated to obtain complex knowledge and the technique demanded by the industry and enterprise. Nowadays in order to adapt to a new business environment, designers specially should have both the knowledge and techniques in engineering and business administration. We suggest that the IPDI, a multidisciplinary design educational system and program is made up of the coordinated operation of major classes, on-the-job training connection, educational system for research base creation, renovation design development program for the application and the synthesis of alternative proposals about the training facility joint ownership by connecting with the education of design, business administration and engineering.