• Journal of the Korean Society of Radiology
• /
• v.11 no.5
• /
• pp.297-302
• /
• 2017

Recently, building materials and air purification filters with eco-friendly charcoal are actively studying to reduce the concentration of radon gas in indoor air. In this study, radon reduction performance was assessed by designing and producing new panel-type activated carbon filter that can be handled more efficiently than conventional charcoal filters, which can reduce radon gas. For the fabrication of our panel-type activated carbon filter, first the pressed molding product after mixing activated carbon powder and polyurethane. Then, through diamond cutting, the activated carbon filter of 2 mm, 4 mm and 6 mm thickness were fabricated. To investigate the physical characteristics of the fabricated activated carbon filter, a surface area and flexural strength measurement was performed. In addition, to evaluate the reduction performance of radon gas in indoor, the radon concentration of before and after the filter passes from a constant amount of air flow using three acrylic chambers was measured, respectively. As a result, the surface area of the fabricated activated carbon was approximately $1,008m^2/g$ showing similar value to conventional products. Also, the flexural load was found to have three times higher value than the gypsum board with 435 N. Finally, the radon reduction efficiency from indoor gas improved as the thickness of the activated carbon increases, resulting in an excellent radon removal rate of more than 90 % in the 6 mm thick filter. From the experimental results, the panel-type activated carbon is considered to be available as an eco-friendly building material to reduce radon gas in an enclosed indoor environment.

• Korean Journal of Poultry Science
• /
• v.36 no.1
• /
• pp.69-75
• /
• 2009

The effects of different packaging methods such as aerobic, vacuum, and wrap packaging, on quality characteristics of fresh chicken breast meat during cold storage were investigated. The results show that crude fat content in aerobic packaging method was significantly (P<0.05) higher compared to the others, whereas moisture, protein and ash contents were not significantly different. pH in wrap packaging was increased with storage time and reached the highest values at 10 days. Both lightness and redness of the meat were increased with storage time, but lightness was significantly (P<0.05) higher in wrap packaging than in the others. Thiobarbituric acid (TBA) and volatile basic nitrogen (VBN) values were increased in all treatments at 10 days. VBN at 5 days were over 20 mg%, and TBA values at 10 days were between 0.82~1.05 mg malondialdehyde/kg meat. TBA showed significantly (P<0.05) lower in vacuum packaging compared to the other methods. Therefore, our results suggested that vacuum packaging decreases lipid oxidation of chicken breast meat, thereby enhancing the shelf life, compared to aerobic and wrap packaging methods.

• 한국HCI학회:학술대회논문집
• /
• 2008.02a
• /
• pp.749-753
• /
• 2008

Proprioception defined it as the ability to detect, the spatial position or movement of joints using balance, power of the muscle, agility in the internal parts of the body. In existing study for improvement of proprioception, reaching task training provided a feedback; the assessment was not provided a feedback. But, this has problem that it can not guide a proprioception from situation with visual feedback. Virtual reality technique can solve the problem of way providing feedback during training. In this study, we developed proprioception training program using virtual reality and pilot study is performed. VR task were composed three modes. In mode 1, real-time movement of the body was provided using visual feedback. In mode 2, body position was provided using visual feedback when participant have specific response. And in mode 3, body position was not provided. VR task is performed five sessions at each mode and one session performed one by one a three target. In the result of this study, the moving time toward the target from mode 3 was smaller than the moving time toward the target from mode 1 (p= 0.001). The correlation was statistically significant between mode 2 and mode 3 while be offering visual feedback position of mode 2 1session. But, the correlation was not statistically significant between mode 2 and mode 3 after be offered visual feedback position of mode2 1session (p = 0.012). Training environment of mode 1 shows which training used visual feedback than proprioception. Mode2 can execute training of proprioception because first session acquires visual feedback by proprioception. The next study will be verification of the system for training or assessment by clinical experiment.

• Journal of the Korean Wood Science and Technology
• /
• v.45 no.1
• /
• pp.126-138
• /
• 2017

This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a raw material of wood adhesives. For the purpose, adhesive resins were formulated with NaOH- and $H_2SO_4$-hydrolyzed CF as well as crosslinkers, and then the properties and water resistance of the adhesive resins against hot water were measured. CF was made of mainly keratin-type protein, and no or very low content of heavy metals was detected. Hydrolysis rate of CF increased as NaOH concentration in hydrolysis solutions increased. However, in order to minimize the loss of adhesive property of protein itself by the severe hydrolysis of CF and to seek its proper hydrolysis conditions, NaOH concentrations in hydrolysis solution determined to adjust to 5%, 7.5% and 10%. In the NaOH-hydrolyzed CF, $H_2SO_4$-hydrolyzed CF as a hardener and crosslinker were added to formulate CF-based adhesive resins. Solid content of the resins ranged from 28.3% to 44.8% depending on hydrolysis conditions and type of crosslinker. Viscosity of the resins at $25^{\circ}C$ was very high. However, when the temperature of the resins was increased to $50^{\circ}C$, the viscosity decreased greatly and thus the resins could be applied as a sprayable resin. Retention rate measured to evaluate the water resistance of adhesive resins was the highest in the cured resin formulated with 5% NaOH-hydrolyzed CF and 5% $H_2SO_4$-hydrolyzed CF of 10% based on the solid weight as a hardener. Retention rate depending on crosslinkers added into adhesive resins was the highest phenol-formaldehyde (PF) followed by melamine-urea-formaldehyde (MUF) and formalin. The retention rate of CF-based adhesives formulated with 5% NaOH-hydrolyzed CF, PF and $H_2SO_4$-hydrolyzed CF of 10% and over did not differ statistically from that of commercial MUF resins. All of CF-based adhesives formulated with PF as a crosslinker and one with 5% NaOH-hydrolyzed CF of 55%, 5% $H_2SO_4$-hydrolyzed CF of 15%, and MUF of 30% on the basis of solid weight could be substituted for commercial urea-formaldehyde resins, From the results, CF can be used as a raw material of wood adhesives if hydrolyzed in proper conditions.

• Journal of Animal Science and Technology
• /
• v.55 no.5
• /
• pp.483-488
• /
• 2013

To develop a sustainable composting method for livestock mortality, a natural aeration-composting process was designed and the influences of bulking materials on the mortality composting process were studied. Bulking materials (e.g., compost, swine manure, sawdust, and rice husks), easily supplied at the scene of an animal mortality outbreak, were tested in this research. A lab-scale composting system (W34 ${\times}$ L60 ${\times}$ H26 cm) was made using 100 mm styrofoam, and natural aeration was achieved through pipes installed on the bottom of the system. Four treatments were designed (compost, compost + swine feces, sawdust, and rice husks treatment groups) and all experiments were done in triplicates. During composting for 40 days, no leachate was observed in compost and sawdust treatment groups, whereas 18 and 8.2 ml leachate/kg-mortality was emitted from the compost + feces and rice husks treatment groups, respectively. Dimethyl disulfide (DMDS) emission during the composting was very low in all treatment groups, possibly due to the bio-filtering function of the compost cover layer on the pile. The mortality degradability in compost, compost + feces, sawdust, and rice husks groups was 25.3, 25.8, 13.5, and 14.5%, respectively, showing significantly higher levels in compost and compost + feces groups (p<0.05). Also, only the compost + feces group produced enough heat (over $55^{\circ}C$) and lasted for 7 days, indicating that bio-security cannot be guaranteed without feces supplementation.

• The Journal of Engineering Geology
• /
• v.13 no.3
• /
• pp.293-308
• /
• 2003

New results about the crustal structure down to a depth of 60 km beneath North Korea were obtained using the seismic tomography method. About 1013 P- and S-wave travel times from local earthquakes recorded by the Korean stations and the vicinity were used in the research. All earthquakes were relocated on the basis of an algorithm proposed in this study. Parameterization of the velocity structure is realized with a set of nodes distributed in the study volume according to the ray density. 120 nodes located at four depth levels were used to obtain the resulting P- and S-wave velocity structures. As a result, it is found that P- and S-wave velocity anomalies of the Rangnim Massif at depth of 8 km are high and low, respectively, whereas those of the Pyongnam Basin are low up to 24 km. It indicates that the Rangnim Massif contains Archean-early Lower Proterozoic Massif foldings with many faults and fractures which may be saturated with underground water and/or hot springs. On the other hand, the Pyongyang-Sariwon in the Pyongnam Basin is an intraplatform depression which was filled with sediments for the motion of the Upper Proterozoic, Silurian and Upper Paleozoic, and Lower Mesozoic origin. In particular, the high P- and S-wave velocity anomalies are observed at depth of 8, 16, and 24 km beneath Mt. Backdu, indicating that they may be the shallow conduits of the solidified magma bodies, while the low P-and S-wave velocity anomalies at depth of 38 km must be related with the magma chamber of low velocity bodies with partial melting. We also found the Moho discontinuities beneath the Origin Basin including Sari won to be about 55 km deep, whereas those of Mt. Backdu is found to be about 38 km. The high ratio of P-wave velocity/S-wave velocity at Moho suggests that there must be a partial melting body near the boundary of the crust and mantle. Consequently we may well consider Mt. Backdu as a dormant volcano which is holding the intermediate magma chamber near the Moho discontinuity. This study also brought interesting and important findings that there exist some materials with very high P- and S-wave velocity annomoalies at depth of about 40 km near Mt. Myohyang area at the edge of the Rangnim Massif shield.

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.1
• /
• pp.67-72
• /
• 2018

This study was conducted to investigate a potential of Yellow poplar (Liriodendron tulipifera L.) as a raw material for the manufacturing of particleboard (PB) and oriented strandboard (OSB). PB panels were prepared at the parameters of $0.7g/cm^3$ density, 15 mm thickness, three-layer, $E_1$ grade urea-formaldehyde (UF) resin, emulsion wax, and hardener. OSB panels were manufactured with a density of $0.65g/cm^3$, thickness of 10 mm, and $E_1$ grade of UF resin. Particle size of the face layer of PB was 20~80 mesh with 7~9% moisture content (MC), while that of core-layer was 3~20 mesh with 3~5% MC, which was similar to the production condition of commercial PB. As a result, the manufactured PB panels with 15.8 mm thickness, $0.7g/cm^3$ density, and 5.8% MC satisfied the requirement of bending strength of 15 type PB of Korean Industrial Standard (KS F 3104). Both internal bonding (IB) strength and surface screw withdrawal resistance also satisfied the requirement of 18 type PB of the standard. But, the edge screw withdrawal resistance satisfied the requirement of 15 type PB of the standard. These differences in properties could be due to the slenderness ratio of raw particles. In case of OSB panels with 10.7 mm thickness, $0.68g/cm^3$ density, and 5.8% MC satisfied all the requirements of bending strength, screw withdrawal resistance, and IB strength of 18 type PB of the standard. These results suggest that Yellow poplar wood has a good potential as a raw material for the production of PB and OSB.

• Research in Plant Disease
• /
• v.16 no.1
• /
• pp.21-26
• /
• 2010

Viral diseases, especially Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV) have been most serious in barley fields. In this study, we investigated the effect of different level of resistance to viral diseases on the plant growth and yield in malting barley. In diagnosis of virus infection, BaYMV and BaMMV were detected in 'Doosan 29' (susceptible), however, 'Jinyangbori' (moderate susceptible) and 'Hopumbori' (moderate) was infected by only BaYMV. Plant height was restrained about 8~29% in overwintered plant regeneration stage depending on the resistant of each cultivar. The culm length damaged also to 9~12% by BaYMV infection. The tiller numbers reduced to 10~14% in overwintering season, however, the head numbers in harvest season more decreased to 26~33%. Heading date was delayed to 3~3 days by the infection. In examination of yield components, 1,000 kernel weight and $\ell$ weight reduced according to culrivar's resistant degrees to 4.0~6.4% and 1.0~4.2%, respectively. The yield of abortive grain was doubled in BaYMV infection comparing to non-infested field. Three varieties tested in the non-infected field over two years were not significantly different for yield potential with ranges of 509kg~632kg/10a. However, significant yield reduction was observed in 'Saessalbori' and 'Baegdong' with ranges of 77~177kg/10a as compared to 'Hopumbori' (467 kg/10a) when tested in the virus-infected field. Yield potentials of these cultivars reduced by 26~43%, respectively, in the virus-infected field as compared to those in the non-infected field.

• The Journal of Korean Academy of Sensory Integration
• /
• v.13 no.2
• /
• pp.63-73
• /
• 2015

Objective : To report the effects of a specific intervention, the Interactive Metronome$^{(R)}$ (IM), on timing, attention and motor function of a children with ADHD. Methods : The study is case reports about two boys with ADHD. One boy who is born 2008 is attending general elementary school as a first year student (case 1), and another boy who is born 2001 is attending general elementary school as a second year student (case 2). For each case subject, IM training was provided during 3 weeks, from January 2015 to Febrary 2015. Evaluations were performed pre- and post-intervention in order to exam timing, attention and motor skills. The measurements uses in this study are Long Form Assessment (LFA) for the timing, RehaCom screening module for the attention, and Bruininks-Oseretsky Test of Morot Proficiency, second version (BOT-2) for the motor function. Results : The timing function was improved in both cases since both showed reduced response time for all motor tasks of LFA. In terms of attention, case 1 showed improvement of visual attention division, neglect and response Inhibition, and case 2 showed improvement of sustained attention. Lastly, in the BOT-2, case 1 showed improved the percentile rank of short (from 42%ile to 96%ile), and case 2 also showed similar improvement (from 21%ile to 66%ile). Conclusion : This study provides positive evidence that the Interactive Metronome$^{(R)}$ training has positive power to facilitate several body functions such as timing, attention and motor control of children with ADHD, through two case studies.

• The Journal of Korean Society for Radiation Therapy
• /
• v.20 no.2
• /
• pp.91-102
• /
• 2008

Purpose: To enlarge the efficiency of operation and establish a constituency for development of new radiotherapy treatment through database which is established by arranging and indexing radiotherapy related affairs in well organized manner to have easy access by the user. Materials and Methods: In this study, Access program provided by Microsoft (MS Office Access) was used to operate the data base. The data of radiation oncology was distinguished by a business logs and maintenance expenditure in addition to stock management of accessories with respect to affairs and machinery management. Data for education and research was distinguished by education material for department duties, user manual and related thesis depending upon its property. Registration of data was designed to have input form according to its subject and the information of data was designed to be inspected by making a report. Number of machine failure in addition to its respective repairing hours from machine maintenance expenditure in a period of January 2008 to April 2009 was analyzed with the result of initial system usage and one year after the usage. Results: Radiation oncology database system was accomplished by distinguishing work related and research related criteria. The data are arranged and collected according to its subjects and classes, and can be accessed by searching the required data through referring the descriptions from each criteria. 32.3% of total average time was reduced on analyzing repairing hours by acquiring number of machine failure in addition to its type in a period of January 2008 to April 2009 through machine maintenance expenditure. Conclusion: On distinguishing and indexing present and past data upon its subjective criteria through the database system for radiation oncology, the use of information can be easily accessed to enlarge the efficiency of operation, and in further, can be a constituency for improvement of work process by acquiring various information required for new radiotherapy treatment in real time.