• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.19-25
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• 2005

Recycling of waste materials in the construction Industry is a useful method that can cope with an environment restriction of every country. In this study, synthetic lightweight aggregates are manufactured with recycled plastic and fly ash with 12 percent carbon. Nominal maximum-size aggregates of 9.5 mm were produced with fly ash contents of 0, 35, and $80\%$ by the total mass of the aggregate. An expanded clay lightweight aggregate and a normal-weight aggregate were used as comparison. Gradation, density, and absorption capacity are reported for the aggregates. Five batches of concrete were made with the different coarse aggregate types. Mechanical properties of the concrete were determined including density, compressive strength, elastic modulus, splitting tensile strength, fracture toughness, and fracture energy. Salt-scaling resistance, a concrete durability property, was also examined. Compressive and tensile strengths were lower for the synthetic aggregates; however, comparable fracture properties were obtained. Relatively low compressive modulus of elasticity was found for concretes with the synthetic lightweight aggregate, although high ductility was also obtained. As nv ash content of the synthetic lightweight aggregate increased, all properties of the concrete were improved. Excellent salt-scaling resistance was obtained with the synthetic lightweight aggregate containing 80 percent fly ash.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.254-258
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• 2005

The purpose of this study is to characterize the indoor-outdoor relationship of airborne pollutants and recognize probable sources in inside and outside individual apartments in Seoul metropolitan. Simultaneous air monitoring in inside and outside of the 16 Korean Apartments classified into 2groups: less than 1 year old and more than 4 years old from October, 2004 to February, 2005were sampled f3r airborne pollutants(volatile organic compounds, formaldehyde, respiratory particles, carbon dioxide and bacteria) using the Korean Indoor Air Quality Official Method. The concentrations of $CO_2$, TVOCs, HCHO, bacteria and PM10 in the less than 1 year old apartments were determined to be $773.6{\pm}422.3ppm$, $4,393.8{\pm}2,758.2{\mu}g/m^3$, $98.0{\pm}56.4{\mu}g/m^3$, $254.0{\pm}186.3CFU/m^3$ and $31.7{\pm}14.8{\mu}g/m^3$, respectively, Also, the concentrations of those in the more than 4 years old apartments were determined to be $798.9{\pm}266.5ppm$, $792.7{\pm}398.3{\mu}g/m^3$, $70.0{\pm}30.7{\mu}g/m^3$, $245.6{\pm}122.0CFU/m^3$, $49.7f28.7{\pm}g/m^3$, respectively. The average ratios of the indoor and outdoor concentrations of $CO_2$, TVOCs, HCHO, bacteria and PM10 were 2.2, 3.6, 3.1, 3.9 and 1.4, respectively. These results of this analysis is suggested that $CO_2$, TVOCs, HCHO, bacteria and PM10 in indoor air are both emitted from source within the apartment environment and partly come from outdoor air. With the above considerations in mind, it is suggested that the research for source contribution of indoor air pollutants should be expanded and the detailed interpretation of the results on these needed further study(using principal component analysis(PCA).

• Journal of Korea Water Resources Association
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• v.38 no.10 s.159
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• pp.801-810
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• 2005

The lag time is one of the most important factors for estimating a flood runoff from streams. It is well known to be under the influence of the morphometric properties of basins which could be expressed by catchment shape descriptors. In this paper, the notion of the geometric characteristics of an equivalent ellipse proposed by Moussa(2003) is applied for calculating the lag time of geomorphological instantaneous unit hydrograph(GIUH) at the basin outlet. The lag time is obtained from the observed data of rainfall and runoff by using the method of moments suggested by Nash(1957), and the procedure based on geomorphology is used for GIUH. The relationships between the basin morphometric properties and the hydrological response are discussed as applied to 3 catchments In Korea. Additionally, the shapes of equivalent ellipse are examined how then are transformed from upstream area to downstream one. As a result, the relationship between the hydrological response and descriptors is shown to be comparatively good, and the shape of ellipse is presented to approach a circle along the river downwards. These results may be expanded to the estimation of hydrological response of ungauged catchment.

• The Journal of the Korea Contents Association
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• v.17 no.3
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• pp.444-453
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• 2017

Moral education is essential to the military in fostering elite warriors to have clear sense of their nation and the security, while arming themselves with military spirit that strives for victory. To reach this goal, various moral education has been set forth through boot camp training, academic education, unit training, etc. depending on various subject and supporting agencies in question. Also, in order to heighten the effect of the education, various attempts to combine concert-style cultural activities with the programs are carried out. However, the ultimate goal for this moral education is to facilitate soldiers to voluntarily set their minds and will in combat, and the current education system lacks that motivation as it concentrates mostly on educating knowledges about nationality and security. Under such circumstances, various units have attempted to raise morality in creating many public and media activities within the unit, which proven to be successful. In theory, the usual definitions in the field of education such as emotion, interest, attitude, and personality can be expanded upon with public and media activities. With this in mind, we have researched on how effective this method is by conducting various public and media activities in multiple units, total of 531 soldiers, starting from June to July of 2016. As a result, these activities brought positive effects on young soldiers to build pride in their assigned units, and also increased their willingness to carry out their assignments and missions. Through this research, we drew to the conclusion that unit-level public and media activities, which was solely used for gaining trust and communicate with the general civilians, can be used to boost the soldiers moral strength and help them express the strength in action.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.495-501
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• 1993

This experiment was carried out to find out the dormancy physiology, method of softening culture and evaluation of nutritional value of wild garlic, Ulrung-native Allium victorialis var. platyphyllum. In March, a new bulbs, the shoot and bulbs began to develop until the bulbs showed their complete dormant states in late August. The bulbs renewed to another one in every years. When shoots germinated about $1{\sim}2\;cm$ from mother bulbs, the soft tissues in the mother bublbs was degenerated and finally remained as only fiberous tissues unlike the other bulbaceous plants. There was a high inhibiting activities like ABA in the bulbs. This is believed that this inhibiting substance like ABA in the bulbs is related to the dormancy of wild garlic. Although the immatured bulbs, harvested at May and June, was treated with chilling for 90 days, it didn't germinate their shooting, but the matured bulbs, harvested at July and August, could germinate their shooting over 1 cm in 75 and 60 days chilling treatment, respectively. The shoot elongation was promoted by the longer chilling periods, the later harvesting day and the dark condition. The crude fiber content of leaf and stem increased at more expanded leaf and higher light intensity condition. Since the shoots, grown from germinating to leaf expanding time, had a good quality for food stuff and had less crude fibers, we supposed this period is to be most appropriate for harvesting time.

• Applied Biological Chemistry
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• v.45 no.4
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• pp.207-211
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• 2002

This study was conducted to increase the shelf life of grape by edible coating material such as methyl cellulose (MC) with antimicrobial substances, n-capric acid isopropyl ester (ci) and sodium nitrate (sn), added by spraying method. The quality changes of packaged grapes with wrapping PE film on EPS tray were investigated for 16 days at $30{\circ}C$. The shelf-lives of C and MCci based on the weight reduction ratio of 7% were 6 days and 9 days, respectively. The reduction rate of acidity of C was higher value than those of treatments during 18 days of storage at $30{\circ}C$. The vitamin C reduction ratios of C, MCsn and MCci were 64.8, 51.5 and 49.8%, respectively, after 16 days at $30{\circ}C$. The reduction rates of firmness of C, MCsn and MCci after 16 days at $30{\circ}C$ were 44.2, 26.5, and 23,2%, respectively compared to that of initial storage grapes. The additions of ci and sn had much affected the reductions of bacteria and yeast counts especially early stage of storage. The hedonic sensory evaluation scores of MCci and MCsn had higher values than those of MC.

• Archives of design research
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• v.19 no.5 s.67
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• pp.55-64
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• 2006

As digital systems were introduced to automotive design in the mid 1980s, the design process has adopted many digital programs to save time compared to the conventional hand drafting. Digital technology was introduced not only to satisfy the reeds of the global environment, as the number of automobiles exported to many different parts of the world has increased, but also to save time and effort in developing several models of quality automobiles. Therefore, every automotive manufacturer in the world has expanded its virtual reality(VR) studio to establish visualization systems that visualize automobiles in the actual size and a co-operation system that enables simultaneous feedback from all of its design studios around the world. Unlike the existing design reviewing methos, the new improved feedback system is assessed as a reasonable method to evaluates and understand how the automobiles are actually manufactured in simulation. It is especially helpful when advanced products and concept cars require fast results. Other strengths of the new system include shorter development period, cost efficiency, no more manual labor, various designs within a short period of time, and realistic visualization of concepts. Large-scale products, including automobiles, need to be projected in the actual size and high clarity through the Power-wall System and are examined in a virtual space called a Cave. Therefore, it took much time to establish digital infrastructure. An infrastructure would constantly require system improvement and performance enhancement, but it is certain that now is the right time for the take-off to utilizing the strengths of digital design and improve the weaknesses. In this respect, this study provided an understanding of the importance of digital design based on digital reinforcements and examined an effective utilization of digital technology for an efficient development of automobiles in the future.

• Journal of the Korean Institute of Gas
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• v.22 no.2
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• pp.46-51
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• 2018

Hydrogen sulfide from landfill and sewage treatment plant is a major odor component and causes many civil petitions. Rapidly developing industries release hydrogen sulfide, an odorous gas, to the atmosphere. This study aims to develop a $10{\mu}mol/mol$ concentration level hydrogen sulfide primary standard gas for odor measurement. The hydrogen sulfide gas was prepared at a nominal concentration of $10{\mu}mol/mol$ in nitrogen using the gravimetric method described in ISO 6142. Replicate standard gases were produced in 4 aluminium cylinders, and their concentrations were verified by GC-AED. The uncertainty of production was less than 0.50 %, and the variation of the 4 replicates was 0.22 %. The wall adsorption of hydrogen sulfide in cylinders was 0.10 % at 1500 psi, and the concentration was estimated to be long-term stable for one year. The relative expanded uncertainty of the preparation consistency, adsorption and long-term stability of this hydrogen sulfide standard gas was less than 1.05 % (95 % of confidence level, k=2).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.24-30
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• 2018

As the demand for underground space increases, many researchers have been studying the load reduction method using high compressible materials to solve for the stability problem of the overhead load and for the increase of the earth pressure which decreases the function of the underground structure. This paper determines the optimum soft zone and the effect of the using EPS Geofoam as a load reduction material to arch structures. A finite element analysis program, ABAQUS, is used to analyze the soil-structure interaction and the behavior of buried arch structures considering different four EPS Geofoam forms to confirm the most conservative shape. The optimum cross-sectional shape was determined by comparing the results of earth pressure reduction rate in accordance with the change of span-rise ratio and span length of the arch structure. It was confirmed that the earth pressure generated in the arch structure using the optimal soft zone selected by the numerical analysis was reduced by an average of 78%. In this study, the effect of EPS Geofoam on soil pressure reduction and its applicability to underground arch structures will provide an economical and conservative way to design underground structures and will help to increase the usability of deep underground space.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.880-884
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• 2001

Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.