• KSBB Journal
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• v.23 no.1
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• pp.90-95
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• 2008

In this study, a combined process of sequential anaerobic-aerobic digestion (SAAD), fluidized-bed bioreactor (FBBR), and ultrafiltration (UF) for the treatment of small scale food waste leachate was developed and evaluated. The SAAD process was tested for performance and stability by subjecting leachate from food waste to a two-phase anaerobic digestion. The main process used FBBR composed of aerators for oxygen supply and fluidization, three 5 ton reaction chambers containing an aerobic mesophilic microorganism immobilized in PE (polyethylene), and a sedimentation chamber. The HRTs (hydraulic retention time) of the combined SAAD-FBBR-UF process were 30, 7, and 1 day, and the operation temperature was set to the optimal one for microbial growth. The pilot process maintained its performance even when the CODcr of input leachate fluctuated largely. During the operation, average CODcr, TKN, TP, and salt of the effluent were 1,207mg/L, 100mg/L, 50 mg/L, and 0.01 %, which corresponded to the removal efficiencies of 99.4%, 98.6%, 89.6%, and 98.5%, respectively. These results show that the developed process is able to manage high concentration leachate from food waste and remove CODcr, TKN, TP, and salt effectively.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.766-773
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• 2013

A transparent film was fabricated based on bacterial cellulose (BC), BC has excellent physical strength and stability at high temperature and it is an environmental friendly flexible material. In order to improve the conductivity, silver nanowire (AgNW) and/or graphene were introduced to the BC membrane. The aspect ratio of the AgNW synthesized in this study was 214, with a length of $15{\mu}m$ and width of 70 nm. The higher aspect ratio improved the conductivity by reducing the contact resistance. The thermal and electrical properties of 7 types of films prepared were investigated. Each film was fabricated with rectangular shape ($2mm{\times}2mm{\times}50{\mu}m$). The films were scored with a net shape by a knife, and filled with AgNW and graphene to bestow conductivity. The film filled with AgNW showed favorable electrical characteristics with a thickness of $350{\mu}m$, electron concentration of $1.53{\times}10^{19}$, electron mobility of $6.63{\times}10^5$, and resistivity of 0.28. The film filled with graphene had a thickness of $360{\mu}m$, electron concentration of $7.74{\times}10^{17}$, electron mobility of 0.17, and resistivity of 4.78. The transmittances at 550 nm were 98.1% and 80.9%, respectively. All the films were able to light LEDs bulbs although their brightness differed. A thermal stability test of the BC and PET films at $150{\pm}5^{\circ}C$ showed that the BC film was more stable, whereas the PET film was quickly banded. From these results, it was confirmed that there it is possible to fabricate new transparent conductivity films based on BC.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.211-220
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• 1994

The critical need of forest road for enchanting the additional values of various forest products, in addition, giving more recreational opportunity to citizen, has been recognized. In this study the present author aimed to ascertain the most effective construction working plan of forest road being tit to Korean geographic condition. To execute this research program, four locations in national forest of Kangweon-do district and other four locations in private forest in Chollabuk-do district both where forest roads have previously been constructed were selected to analyze the effectiveness basing upon the various factors separately or in combination. The results are summarized as follows ; 1. The investment efficiency in forest road construction showed to increase in the area where terrain factors and district social factors rate is high, and to decrease in the area where forest status factors and forest road structure factors rate is high. So in future the Forest Resource Development Model of forest road should take more importance particularly on those area having terrain factor ratio is low. The extractable value of constructed forest road based on forest status factors rate is expected to increase in case of high considerably. 2. To construct of forest road for increasing multiple use of forests, forest road should be construct with priority on area where obtained total score by evaluation factors is high. And these evaluation factors should take possible determine the position of forest road construction. 3. The following five types of forest road basing upon function performance are suggested with regard to the place where road is constructed. (1) Forest Utilization Model ; where forest status factors and forest road structure factors rate are over 60%. (2) Forest Resource Development Model ; where terrain factors, forest status factors, forest road structure factors and district social factors rate are less than 60%. (3) Community Development Model ; where terrain factors, forest road structure factors and district social factors rate are over 60% but forest status factors rate are less than 60%. (4) Recreation and Health Model ; where terrain factors, forest status factors, forest road structure factors and district social factors rate are over 60%. (5) Multiple Use Model ; where both forest status factors and district social factors rate are over 60%.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.63-74
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• 2006

During the construction of circular underground pipe, the non-proper compaction along the pipe and the decrease of compaction efficiency have been the main problems to induce the failure of underground pipe or facility. The use of CLSM (controlled low strength materials) should be one of the possible applications to overcome those problems. In this research, the full-scaled field test and the numeric analysis using PENTAGON-3D FEM program were carried out for three different cases on the change of backfill materials, including the common sand, the soil from construction site, and the CLSM. From the full-scaled test in field, the use of in-situ CLSM as backfill materials reduced the vertical and lateral deformation of the pipe, as well as the deformation of the ground surface. The main reason for reducing the deformation would be the characteristics of the CLSM, especially self-leveling and self-hardening properties. The measured earth pressure at the surround of the corrugated pipe using the CLSM backfills was the smaller than the other cases, and the absolute value was almost zero. Judging from the full-scaled field test and FEM analysis, the use of CLSM as backfill materials should be one of the best choices reducing the failure of the underground pipes.

• Journal of Science Education
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• v.32 no.1
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• pp.33-46
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• 2008

The purpose of this study was to know whether or not any wrongful description or simple errors were in photosynthesis unit of Biology II textbook under 7th national curriculum and if so, to know whether or not high school teachers recognized and corrected properly the mistakes. The mistakes in photosynthesis unit of text books were determined by the comparison with several reference books and through examination by three plant physiologists in 8 different Biology II textbooks. After the mistakes were analysed, the survey using contents of textbook containing the mistakes was conducted on high school teachers teaching Biology II. As a result, 48 mistakes were determined in 13 subjects. As many as four mistakes were found even in one subject in a certain textbook and a same mistake was found repeatedly in several textbooks. The survey result showed that the teachers who pointed exactly the mistakes out corrected properly, however, the percentage of these ones out of 35 teachers replied to survey was less than 50%. The ratios of correction out of total number of responses were high in question #6 (43%), #4-3 (40%), and #1-2 (32%) which were containing a simple mistake in graph, a wrong word and a wrong picture, respectively. But, no one pointed out and made correction in question #5-1 and #5-2 which were containing Z scheme of light reaction without the legend of vertical axis that should be explained as electron energy or standard reduction potential. The result indicates the possibility that the mistakes in photosynthesis unit of Biology II textbook can be corrected and teached properly by teachers may be low. In order to reduce the possibility that students may have misconceptions about photosynthesis, the list of print's errors should be provided to the teachers and/or the training program and/or workshop for in-service high school biology teachers was recommended.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.835-854
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• 2017

Government regulations and policies are important means of restraining the indiscreet expansion of urban areas. According to the standards from those means, it is clear that the fluctuation of forest green proportion encroached by the increase of urban space is obvious. In this study, we interpreted the changes of urban areas as well as the green ones owing to the urban expansion by the decades from 1996, with focusing on the cities of Seoul and Daegu highly developed in South Korea. The purpose of this study is to analyze the spatial expansion and morphological characteristics of urban land cover using not only satellite imageries (1996, 2006, 2016). but also the urban expansion intensity index (UEII) and GUIDOS program. Ultimately, this study is to compare the changes in the rate of forests due to urban expansions annually analyzed based on areas of forest elevation, slope, and the area of single forest patch. In Seoul, the expansion begun from urban space to suburban areas was comparatively rapid, which led the forest fragmentation and the gradual decline of the single patch. However, when it comes to DEM (Digital elevation model) and slope above a certain standard, by the development regulations, there was little decrease in area by anthropogenic developments. The city of Daegu has increased at a slow speed since 1996 in urban and suburban areas, whereas green forests have greatly increased through green forest conservation campaigns. In this way, as to the government policies and regulations, the quantitative and morphological expansion of cities owing to development could be controlled and forest spaces could be preserved as well. Therefore, regulations and policies by the government should be appropriately utilized for sustainable cities.

• Korean Security Journal
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• no.21
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• pp.155-175
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• 2009

RFID that provide automatic identification by reading a tag attached to material through radio frequency without direct touch has some specification, such as rapid identification, long distance identification and penetration, so it is being used for distribution, transportation and safety by using the frequency of 125KHz, 134KHz, 13.56MHz, 433.92MHz, 900MHz, and 2.45GHz. Also it is one of main part of Ubiquitous that means connecting to net-work any time and any place they want. RFID is expected to be new growth industry worldwide, so Korean government think it as prospective field and promote research project and exhibition business program to linked with industry effectively. RFID could be used for access control of person and vehicle according to section and for personal certify with password. RFID can provide more confident security than magnetic card, so it could be used to prevent forgery of register card, passport and the others. Active RFID could be used for protecting operation service using it's long distance date transmission by application with positioning system. And RFID's identification and tracking function can provide effective visitor management through visitor's register, personal identification, position check and can control visitor's movement in the secure area without their approval. Also RFID can make possible of the efficient management and prevention of loss of carrying equipments and others. RFID could be applied to copying machine to manager and control it's user, copying quantity and It could provide some function such as observation of copy content, access control of user. RFID tag adhered to small storage device prevent carrying out of item using the position tracking function and control carrying-in and carrying-out of material efficiently. magnetic card and smart card have been doing good job in identification and control of person, but RFID can do above functions. RFID is very useful device but we should consider the prevention of privacy during its application.

• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.217-224
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• 2004

This study was carried out to investigate the antibiotic resistance pattern of Listeria spp. and Staphylococcus aureus. A total of 17 (14.8%) L. monocytogenes, 13 (11.3%) L. innocua, 7 (7%) L. welshimeri, and 83 (72.2%) S. aureus were isolated from commercial poultry carcasses in Seoul and Kyonggi province during the period between 2001 and 2003. Antibiotic susceptibility test of all Listeria strains isolated was performed by the disk agar diffusion method. Antibiotics used in the study were as follows; Amikacin (An), Ampicillin (Am), Cephalothin (Cf), Chloramphenicol (C), Ciprofloxacin (Cip), Erythromycin (E), Gentamicin (Gm), Imipenem (Ipm), Kanamycin (K), Minocycline (Mi), Neomycin (N), Norfloxacin (Nor), Ofloxacin (Ofx), Penicillin (P), Streptomycin (S), Tetracycline (Te), Tobramycin (Nn), Trimethoprim (Tmp), Trimethoprim/Sulfamethoxazloe (Sxt), and Vancomycin (Va). The antibiotic resistance pattern of S. aureus isolates was performed by the disk agar diffusion method. For the latter program, antibiotics used to the study were as follows; Cf, C, Cip, Clindamycin (Cc), E, Gm, Ipm, Nafcillin (Nf), Oxacillin (Ox), P, Te, Sxt, and Va. Of the 17 L. monocytogenes isolates, 94.1% were resistant to Te, 88.2% to Mi, 11.8% to Nor, 11.8% to S, 5.9% to Cip, and 5.9% to C. Of 13 L. innocua, 53.8% were resistant to Te, 23.1% to Mi, 23.1% to S, 7.7% to Cip, and 7.7% to Nor. Of 7 L. welshimeri, 57.1% were resistant to Te, and 14.3% to Am. Of 83 S. aureus, 100% were resistant to Te, 86.7% to Gm, 34.9% to P, 15.7% to Cip, 12% to Cc, 9.6% to E. The multiple antibiotic resistance patterns of L. monocytogenes isolates were observed in Te Mi Cip (5.9%), Te Mi Nor (5.9%), Te Mi (76.5%), and Te Nor (5.9%). Multiple antibiotic resistance was also found in L. innocua isolates. Resistant to Te Mi S Cip Nor was 7.7%, Te Mi S (7.7%), Te Mi (7.7%), and was 7.7% to Te S. Antibiotic resistance patterns for S. aureus isolats were demonstrated to Te Gm P Cip Cc E (6.0%), Te Gm Cip Cc E (3.6%), Te Gm P Cc (1.2%), Te Gm P (15.6%), Te Gm Cip (2.4%), Te P Cip (2.4%), Te Gm Cc (1.2%), Te Gm (56.6%), Te P (9.6%), and to Te Cip (1.2%). The results of this study suggest a high incidence of Lsteria spp. and S. aureus on poultry carcasses. The contaminated poultry carcasses may be a potential vehicle for foodborne infections due to multiple antimicrobial resistant organisms.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.756-763
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• 2013

Mechanical hair removal of carrot seed causes seed injuries and suppresses the germination in carrot cultivation. This study was performed to develop molecular markers for breeding high quality cultivars with short-hair seed. To meet this objective, random amplified polymorphic DNA (RAPD)-sequence characterized amplified region (SCAR) markers specifically linked to seed-hair characteristic were identified using CT-SMR 616 OP 389-1 line with short-haired seed and CT-SMR 616 OP 616-33 line with long-haired seed, bred by self-pollination for 6 years from 2008 to 2013, as parents. After seed hair lengths of these lines were analyzed using microscope, next generations were advanced and compared with the molecular markers polymorphism. From RAPD analysis using fixed lines in 2011, twelve RAPD primers showing polymorphic bands specific between the two lines were identified from 80 random primers. To develop RAPD-SACR marker, SCAR primers were designed based on sequence analysis of these specific RAPD bands and more than three combinations of primers were tested. As a result, it was found that the $SCA2_{1.2}$ amplified single polymorphic band from short-haired seed line. To confirm this result, $SCA2_{1.2}$ marker was retested by applying to the 2012 and 2013 progenies. Finally, it was concluded that the developed $SCA2_{1.2}$ marker distinguished short-haired line from long-haired seed line. Therefore, SCAR marker, $SCA2_{1.2}$ is expected to be utilized for breeding of the short-haired seed cultivars.

• Journal of Life Science
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• v.19 no.12
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• pp.1750-1757
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• 2009

The purpose of this study was to investigate the effects of regular walking exercise on health-related parameters in the elderly with chronic diseases - apoplexy, overweight, impaired fasting glucose, and overweight + impaired fasting glucose. A total of 85 subjects, 27, 17, 21 and 20 in apoplexy (A), overweight (O), impaired fasting glucose (IFG), overweight + impaired fasting glucose group (O_IFG), respectively, completed a 12-week walking exercise. The health-related parameters were measured before and at the completion of the exercise program including anthropometric measurements, functional physical fitness levels, blood pressure, fasting glucose, blood lipid profiles and chronic inflammatory markers (CRPs). Significant improvements in body weight, BMI, %body fat, blood pressure, all blood lipid measurements and all measured physical fitness items were shown in A; those in %body fat, TC, HDL-C and LDL-C in O; those in body weight, BMI, %body fat, fasting glucose, TC, TG and HDL-C in IFG; and those in body weight, HDL-C and LDL-C in O_IFG (p<0.05). The results of the present study demonstrated that a 12-week walking exercise brought positive effects on body weight, bloody lipid profiles, fasting glucose and functional physical fitness levels in the elderly with chronic diseases. In conclusion, this study suggested that walking regularly is very effective in lowering the risks of developing chronic diseases.