• Clean Technology
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• v.25 no.4
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• pp.316-323
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• 2019

In order to enhance combustion efficiency and reduce atmosphere pollutants, it is essential to measure carbon monoxide (CO) concentration precisely in combustion exhaust. CO is the important gas species regarding pollutant emission and incomplete combustion because it can trade off with NOx and increase rapidly when incomplete combustion occurs. In the case of a steel annealing system, CO is generated intentionally to maintain the deoxidation atmosphere. However, it is difficult to measure the CO concentration in a combustion environment in real-time, because of unsteady combustion reactions and harsh environment. Tunable Diode Laser Absorption Spectroscopy (TDLAS), which is an optical measurement method, is highly attractive for measuring the concentration of certain gas species, temperature, velocity, and pressure in a combustion environment. TDLAS has several advantages such as sensitive, non-invasive, and fast response, and in-situ measurement capability. In this study, a combustion system is designed to control the equivalence ratio. Also, the combustion exhaust gases are produced in a Liquefied Petroleum Gas (LPG)/air flame. Measurement of CO concentration according to the change of equivalence ratio is confirmed through TDLAS method and compared with the simulation based on Voigt function. In order to measure the CO concentration without interference from other combustion products, a near-infrared laser at 4300.6 cm^-1 was selected.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.22 no.3
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• pp.95-102
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• 2016

This study investigated the effects of the oxygen permeability of vacuum packaging film and the storage temperature on the quality and shelf life of Hamburg steaks during storage for 14 days. Control samples (C) were packaged in a polyamide/polyethylene (PA/PE) film and stored at $5^{\circ}C$. Treatment samples were either packaged in an ethylene vinyl alcohol/polyethylene (EVOH/PE) copolymer film and stored at $5^{\circ}C$ (T1), and in a PA/PE film and stored at $-18^{\circ}C$ (T2). The initial total plate count (TPC) was 3.6 log cfu/g. In T1 samples, TPC and Brochothrix thermosphacta counts were increased, similar to those in C samples, whereas Pseudomonas spp. counts were significantly lower than those in C samples during storage. Over the storage period, the volatile basic nitrogen values increased most rapidly in C samples, followed by T1 and then T2 samples. The values of thiobarbituric acid reactive substances steadily increased in all samples during storage. The colour parameters were not significantly different among the samples during storage. T1 samples maintained sensory qualities in flavour and off-odour parameters for two days longer than C samples did. At day 12, T2 samples were evaluated as being below the marketability score of 5.0 for texture. In conclusion, using high oxygen barrier films like EVOH/PE copolymer for packaging Hamburg steaks could extend the sensory qualities in view of flavour and off-odour during chilled storage. However, frozen storage at $-18^{\circ}C$ is recommended when the storage period is extended beyond 14 days at $5^{\circ}C$.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.149-155
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• 1995

Background: Cytokeratin 19 is 40KD acidic molecule whose distribution is restricted to simple or pseudo-stratified epithelia, such as the epithelial layer of the bronchial tree. Immunohistochemical study have shown that cytokeratin 19 is overexpressed in lung carcinoma tissue. An immunoradiometric assay, CYFRA 21-1 has been developed using two monoclonal antibody, BM 19-21 and KS 19-1, reactive to different epitopes on cytokeratin 19. We studied the diagnostic value of CYFRA 21-1 in lung cancer. Method: The serum CYFRA 21-1 level using immunoradiometric kit(ELSA-CYFRA 21-1) was measured in 54 patients who admit to Yeungnam University Hospital from April, 1993 to August, 1994. Lung cancer group was 39 primary lung cancer patients(19 patients with squamous cell carcinoma, 11 patients with adenocarcinoma and 9 patients with small cell carcinoma). Control group was 15 patients with non malignant lung diseases(8 patients with pulmonary tuberculosis, 3 patients with chronic obstructive pulmonary disease, 2 patients with pneumonia and 2 patients with chronic obstructive pulmonary disease combined with pulmonary tuberculosis). Results: The mean serum value of CYFRA 21-1 was $20.2{\pm}4.7ng/ml$ in squamous cell carcinoma, $7.2{\pm}1.6ng/ml$ in adenocarcinoma and $15.5{\pm}4.7ng/ml$ in non-small cell lung cancer. The serum value of CYFRA 21-1 in control group was $1.7{\pm}0.5ng/ml$. All of the serum values of 3 histologic types were significantly higher than that of control group(p<0.01). The serum value of CYFRA 21-1 of squamous cell carcinoma was significantly higher than that of adenocarcinoma(p <0.05). Serum value of CYFRA 21-1 in small cell lung cancer was $2.9{\pm}0.9ng/ml$ and not significantly different compared with control group. Using cut off value of 3.3ng/ml, sensitivity and specificity was 11.1%, 65.2% in small cell lung cancer, 70.0%, 62.5% in non-small cell lung cancer, 73.7%, 75% in squamous cell carcinoma and 63.6%, 78.9% in adenocarcinoma, respectively. Conclusion: The serum levels of CYFRA 21-1 may be useful in diagnosis of non-small cell lung carcinoma, especially in squamous cell carcinoma with its high specificity.

• Clean Technology
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• v.18 no.2
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• pp.200-208
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• 2012

This study was performed to prevent the health damage of environmental contaminants in Industrial Complex Area. And, this study aimed to identify the concentration levels and distribution characteristics of environmental contaminants and Polycyclic Aromatic Hydrocarbons (PAHs) at soil in Industrial Complex Area and control area. The concentration of the soil pollution standard such as the heavy metals in the soil, VOCs, PAHs, and PCB were measured and analyzed using the soil specimens in the Industrial Complex Area and control area. Soil specimens from the Industrial Complex Area (the direct exposure area) and the control area were surveyed. Songdo-dong, Haedo-dong and Jechul-dong, which are in the direct exposure area and near the emission source, showed relatively high concentrations of contaminant materials when compared with Jangki-myeon, which is far off and in the control area. The concentration of zinc was 20.8-58.9% of the level of concern (300 mg/kg) in the 1st region, which is a relatively high concentration. The concentration of fluoride was under the standard in every region, but it was about 74% of the level of concern (400 mg/kg) in the 1st region. It is recommended that controlling fluoride emissions is necessary. Levels of organic phosphate, phenol, and VOCs like benzene, toluene, ethylbenzene and xylene were under the detection limit of the analysis instruments. The concentration of TPH was high in Songdo-dong. The concentration of contaminants in Jechul-dong was high. In addition, it was observed that the level of soil contamination changed depending on the distance from the emission source. The concentration of PAH compounds in the soil was 18.71-1744.59 ng/g, and the concentration of six potential cancer-causing PAH materials was 6.54-695.94 ng/g. The highest concentration was in Songdo-dong. The PAH concentration in the direct exposure area near the complex was relatively high compared to the indirect exposure area.

• Journal of Life Science
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• v.25 no.8
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• pp.953-959
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• 2015

Optogenetics is the combination of optical and molecular strategies to control designated molecular and cellular activities in living tissues and cells using genetically encoded light-sensitive proteins. It involves the use of light to rapidly gate the membrane channels that allows for ion movement. Optogenetics began with the placing of light-sensitive proteins from green algae inside specific types of brain cells. The cells can then be turned on or off with pulses of blue and yellow light. Using the naturally occurring algal protein Channelrhodopsin-2 (ChR2), a rapidly gated light-sensitive cation channel, the number and frequency of action potentials can be controlled. The ChR2 provides a way to manipulate a single type of neuron while affecting no others, an unprecedented specificity. This technology allows the use of light to alter neural processing at the level of single spikes and synaptic events, yielding a widely applicable tool for neuroscientists and biomedical engineers. An improbable combination of green algae, lasers, gene therapy and fiber optics made it possible to map neural circuits deep inside the brain with a precision that has never been possible before. This will help identify the causes of disorders like depression, anxiety, schizophrenia, addiction, sleep disorder, and autism. Optogenetics could improve upon existing implanted devices that are used to treat Parkinson’s disease, obsessive-compulsive disorder and other ailments with pulses of electricity. An optogenetics device could hit more specific subsets of brain cells than those devices can. Applications of optogenetic tools in nonneuronal cells are on the rise.

• Journal of the Korean Society of Food Science and Nutrition
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• v.3 no.1
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• pp.47-51
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• 1974

1. As the low standard of living of the people who live in both the model and compared villages, is almose similar to each other, the state of their food intaking has nearly the same degree. 2. The villagers of the two kinds of village mentioned above do not cast off their traditional eating habits getting an energy from rice and vegetarian diet. They, however, have been so much interested in the problem of birth control that they have a few children in less than four-year-old. We have to go on the problems of driving a reasonable family plan, and replacing the traditional food life by taking a fatty food. 3. Their pool life forces them to have an over work for supporting their family. Even though they take much Fe from grains and vegetables day after day, Fe does not give a great influence on making Hb (Erythrocyte) in a body. Accordingly most of them have developed symptoms of anemia. This research, comparing with the research results of Ewha University and Seoul Medical College shows much lack of Hb. So it is need for them to take a large quantity of animal protain and make a healthful habit by reforming their food life.

• Archives of design research
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• v.13 no.4
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• pp.233-242
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• 2000

The traditional image of hydraulic excavator started to change in two ways since 1990. First, post-heavy equipment's visual image was new waves to traditional image of heavy, strong, and wild. They are the negative aspect that excavators have. Another movement of getting rid of its negative image can be found in late-heavy equipment, which was intended to adapt traditional and positive, but off negative images. In 1990s, the design trend is moving from warm/hard to warm/soft, and KOBELCO can be exceptional example that went even further, gone up to cool-soft image. KOBELCO specially aimed 'post- excavator image' strategy, which has been successful. Image of cabin as a human space changed little bit further than outside image. Each company tried to differentiate the design of cabin focusing on its safety. Following paragraphs show specific trend of image change in form, colour, texture, and the composition. Major visual image change in form tries to follow the image of cars and home appliances which are showing the movement from tough and hard image to soft one. Structural change on local image shows the movement from angular edge to edgeless and the movement of cabin's pillar C placed to back of the equipment with gentle inclination. All of these movements are the result of effort to improve traditional excavator's negative image, that top structure is assembled separately, to positive ones. Today's tendency about its color becomes important to apply two different colour styles. Each style has brightness and tone comparison. As an enormous power convey system, it was in common that its brightness comparison was useful because of the alarm of its damage possibility. However, as its colour control and its design have been emphasized gradually, the tone comparison takes a part in an important role, too. As an example, there is an occasion that these comparisons are compromised simultaneously. In the respect of its image creation, its texture treatments make the tendency of being the same as passenger cars. It is caused from its development of the manufacture techniques of from the fabrication method in small business to the press method in big firm. Further, it is also because of its improvement of painting & coating skills. It may prohibit the reflection effect from solar rays. In the point of view of its visual images, it is recognized the prominent tendency that its composition has been gradually decreased. Lots of windows and the frames tends dark-colour as a whole. It is more preferred to have one colour image, but except KOBELCO and HITACHI. As well, there is another high-tendency to improve its standard treatments, especially for its corner and texture treatments.

• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.449-455
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• 2009

The increase of industrial carbonic dioxide emissions has accelerated the carbonation of reinforced concrete structures, which drops off their durability. Although advanced countries have already taken safety control measures against the carbonation of RC structures, it is still difficult now to accurately predict the actual carbonation depth. Additionally, it requires much time and efforts. Recently, it is possible to get the data more rapidly through accelerated carbonation test with the $CO_2$ concentration of 100%. In this paper, the carbonation test results obtained by two test methods such as the normal carbonation test method and the accelerated carbonation test method, were compared to investigate the carbonation characteristics of fly ash concrete. The accelerated carbonation test on concrete specimens with the pre-curing age of 180 days was also carried out to examine the carbonation characteristics of fly ash concrete at long-term age. Consequently, fly ash concrete at early age was vulnerable to carbonation and however, its carbonation resistance at long-term ages was improved compared with OPC concrete.

• Journal of Environmental Science International
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• v.26 no.8
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• pp.967-976
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• 2017

In this study, the effect of probiotic supplementation on growth performance, blood metabolites, and meat quality of Hanwoo steer was investigated. A total of 32 Hanwoo steers (15-17 months, average body weight $462{\pm}37.9kg$) were randomly allotted to 4 dietary treatments (0, 0.5, 1.0, and 1.5% mixed probiotics), with four Hanwoo steers per pen (two replicates per treatments), and reared for 12 months. There were no differences among treatments in growth performance of Hanwoo steer (P>0.05); however, feed intake decreased linearly with increasing levels of mixed probiotics. Growth hormone and Blood Urea Nitrogen (BUN) levels responded linearly with increasing levels of dietary mixed probiotics (P<0.05), but not insulin and blood glucose did not. In particular, total cholesterol was significantly lower for the 1% mixed probiotic treatment in comparison with that of the other treatments (P<0.05). The pH, Thiobarbituric Acid Reactive Substances (TBARS), cooking loss, and meat color were influenced by increasing levels of mixed probiotics (P<0.05), but the carcass characteristics and shear force were not. Regarding sensory evaluation, the addition of mixed probiotics resulted in significant difference in meat color, tenderness, aroma, off-flavor, juiciness, and marbling score, but not in overall acceptability. In addition, fatty acid profiles indicated no differences between control and mixed probiotic treatments. In conclusion, mixed probiotic treatment at 1% levels can enhance consumer preferences possibly by reducing cholesterol and TBARS.

• Journal of The Korean Association For Science Education
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• v.9 no.1
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• pp.19-37
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• 1989

The purpose of this study was to investigate the development of logical thinking and scientific reasoning pattern of Korean high school students. To carry out this study subjects were selected about 2,000 Junior high school students, and about 4,100 senior high school students throughout the nation. They were identified as concrete, transitional or formal operational stage with the use of TOLT(the Test of Logical Thinking) by Tobin and Capie(1980), and TOSR(the Test of Scientific Reasoning) by W.A Farmer(1986). This study turned out that more than 76% of Junior high school students were classified as the concrete operational stage and about 44% of senior high school students were classified as the formal operational stage, while about 26% of them were still in the concrete operational level. This study showed that the main factor of the intellectual development of students is learning by the gradual advancement of their grades and especially entrance into the senior high school rather than by the physical growth. This study also showed that there are the take-off stage of the development of logical thinking between fourteen and fifteen years of their ages. Less than 25% of junior high school students were in the formal operational stages which are capable of control of variables, probabilistic, correlation and combinational logic in problem-solving situation, while 33-54% of senior high school students were in the formal operational levels. 38% of junior high school students were in the formal operational stage which is capable of proportional logic, while about 55% of senior high school students were in the formal operational stage. Less than 20% of senior high school students were classified as group of highly capable of scientific reasoning, while more than 23% of them were classified as group of poor capability. It also turned out that there are differences or no differences between male and female students of each school in problem-solving situation regarding each logic approach. These differences were proved to be fluctuating depending on the situations and their grades. The other results of this study is similar to those of other researches such as Tomlinson-Keasey 1972, Coleman 1973, Lawson 1973, Lawson and Renner 1974, Neimark 1975, Han 1982, and Kim 1989.