• Journal of the Korean Institute of Rural Architecture
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• v.25 no.4
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• pp.9-16
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• 2023

In this study, the status and characteristics of fine dust and its impact on neighboring areas were investigated to proactively respond to the government's environmental regulations expected in the future and to minimize the damage by the fine dust generated at construction waste intermediate treatment plants. In addition, since there are no such plants that can affect the surroundings with no houses or other waste treatment sites nearby, an independently located construction waste intermediate treatment plant was selected to compare the characteristics of fine dust with that from the construction waste intermediate treatment sites located in the downtown area. The conclusions of the study are as follows. (1) The measurement results of PM10 at 4 points in the plant showed that the location where the crushing facility was operating had an elevated level of fine dust at 80㎍/m³ on average and a maximum of 124㎍/m³, and the level rose to 110㎍/m³ at points where vehicles frequent. (2) The PM2.5 measurement results inside the plant showed that the average concentration of the reference point was 16㎍/m³ and the maximum value was 20㎍/m³, which was distributed within the management standard. (3) It was found that the average concentration of PM10 in the nearby area ranged from 28 to 38㎍/m³, which was similar to or lower than 36㎍/m³ of the reference point. Therefore, the concentration of the fine dust generated in the plant had a negligible effect on the increase in concentration of fine dust in nearby areas. (4) The heavy metal contents were measured from the filter paper collected from the plant. The PM10 was found to be about 14 to 26ng/m³, and PM 2.5 was 25 to 28ng/m³, which was the average of domestic atmospheric concentrations. (5) The SEM-EDX analysis results showed that the PM10 contained Si and O around 40% similarly for both. The SiO2, a component of silica occupied the most and C was present as CaCO3, which was assumed to be a limestone component. The remaining components included NaO, Al2O3, and CaO as trace oxides. (6) The SEM-EDX analysis results showed that the PM 2.5 contained 5 to 7% of Cl, which is a chlorine ion, and a small amount of K was detected at 2.51% in the sample from the shutdown plant.

• The Journal of the Acoustical Society of Korea
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• v.26 no.7
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• pp.361-365
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• 2007

Aero-pulsation noise, generally caused by geometric asymmetry of a rotating device, is one of considerable sources of annoyance in passenger cars using the turbocharged diesel engine. Main source of this noise is the compressor wheel in the turbocharger system, and can be reduced by after-treatment devices such as silencers, but which may increase the manufacturing cost. More effective solution is to improve the geometric symmetry over all, or to control the quality of components by sorting out inferior ones. The latter is more simple and reasonable than the former in view of manufacturing. Thus, an appropriate discrimination method should be needed to evaluate aero-pulsation noise level at the production line. In this paper, we introduce the accurate method which can measure the noise level of aero-pulsation and also present its evaluation criteria. Besides verifying the reliability of a measurement system - a rig test system-, we analyze the correlation between the results from rig tests and those from vehicle tests. The gage R&R method is carried out to check the repeatability of measurements over 25 samples. From the result, we propose the standard specification which can discriminate inferior products from superior ones on the basis of aero-pulsation noise level.

• The Journal of the Acoustical Society of Korea
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• v.28 no.3
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• pp.222-228
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• 2009

This study compared the sound spectrums of pyeonjong remains and pyeonjong replica to investigate tuning ways of bells. pyeonjong remains, exhibited at King Sejong Memorial Museum and pyeonjong replica, played at the National Center for Korean Traditional Performance Arts were analyzed. To get mode frequencies and mode shapes, pyeonjong replicas' sound spectrums were analyzed and modal analyses by TV holography were performed. Also pyeonjong remains' sound spectrum were analyzed. Nominal frequencies on the pyeonjong replica and remains showed differences in a range between 9.8 cent and 203 cent. Two facts were inferred as causes of the differences, the tuning conditions of pyeonjong remains were not good and C4 in western tempered scale was preferred as the sound standard of Kukak, whangjong. Relative ratio of higher mode frequencies to the nominal frequencies were calculated to figure out tonal differences between two pyeonjongs. The differences in relative ratio of higher mode frequencies except (3,0)a and (3,0)b modes were significants as well as beyond the just noticeable difference. These results implied that the tonal differences between two pyeonjongs could exist. More pyeonjong remains are needed to be investigated to confirm this result in addition to the analyses of alloy components and bell structure of pyeonjong remains and replica.

• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1109-1118
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• 2024

Probiotics, specifically Lacticaseibacillus rhamnosus, have garnered attention for their potential health benefits. This study focuses on evaluating the probiotic properties of candidate probiotics L. rhamnosus IDCC 3201 (3201) using the Caenorhabditis elegans surrogate animal model, a well-established in vivo system for studying host-bacteria interactions. The adhesive ability to the host's gastrointestinal tract is a crucial criterion for selecting potential probiotic bacteria. Our findings demonstrated that 3201 exhibits significantly higher adhesive capabilities compared with Escherichia coli OP50 (OP50), a standard laboratory food source for C. elegans and is comparable with the widely recognized probiotic L. rhamnosus GG (LGG). In lifespan assay, 3201 significantly increased the longevity of C. elegans compared with OP50. In addition, preconditioning with 3201 enhanced C. elegans immune response against four different foodborne pathogenic bacteria. To uncover the molecular basis of these effects, transcriptome analysis elucidated that 3201 modulates specific gene expression related to the innate immune response in C. elegans. C-type lectin-related genes and lysozyme-related genes, crucial components of the immune system, showed significant upregulation after feeding 3201 compared with OP50. These results suggested that preconditioning with 3201 may enhance the immune response against pathogens. Metabolome analysis revealed increased levels of fumaric acid and succinic acid, metabolites of the citric acid cycle, in C. elegans fed with 3201 compared with OP50. Furthermore, there was an increase in the levels of lactic acid, a well-known antimicrobial compound. This rise in lactic acid levels may have contributed to the robust defense mechanisms against pathogens. In conclusion, this study demonstrated the probiotic properties of the candidate probiotic L. rhamnosus IDCC 3201 by using multi-omics analysis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.69 no.2
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• pp.78-87
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• 2024

The risk of global warming is increasing due to rapid climate change and increased greenhouse gas (GHG) emissions. Among the greenhouse gases, methane has a strong warming effect; in particular, 51.2% of the agricultural sector's methane emissions are from flooded rice fields. According to the current standard rice cultivation method, rice is grown during the maximum tillering stage with an intermittent drainage period of approximately 2 weeks. During the flooding period, methane-producing bacteria are active, but the activity of methane-producing bacteria and the amount of methane gas produced are reduced when the soil becomes oxidized through watering. Accordingly, this study used multiple-sensing technology to analyze the growth response according to the intermittent drainage period and to identify the extended intermittent drainage period with less impact on rice production. The equipment used for growth observations included NDVI, PRI, and IR sensors. The results confirmed that growth indices related to stress, such as NDVI and PRI, were not significantly different from those of the control when treated within 3 weeks of drainage, but drastically decreased when the drainage period was extended beyond 4 weeks. These results appear to result from the fact that soil water content (volumetric water content) also dropped to below 20% 4 weeks after irrigation, creating actual drought stress conditions. The 22^nd day after treatment, when the soil moisture content reached 20%, was considered the point in time when drought stress conditions were formed. The point at which the SPAD value decreased to 0.6% of normal was estimated to be 23.5 days after treatment by using the regression equation between NDVI and SPAD.

• Fire Science and Engineering
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• v.26 no.6
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• pp.99-108
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• 2012

These days, spontaneous ignition phenomena by oxidizing heat frequently occur in the circumstances of processing and storing waste tires. Therefore, to examine the phenomena, in this work, this researcher conducted the tests of fires of fragmented waste tires (shredded tire), closely investigated components of the fire residual materials collected in the processing and storing place, and analyzed the temperature of the starting of the ignition, weight loss, and heat of reaction. For the study, this researcher conducted fire tests with fragmented waste tires in the range of 2.5 mm to 15 mm, whose heat could be easily accumulated, and performed heat analysis through DSC and TGA, DTA, DTG, and GC/MS to give scientific probability to the possibility of spontaneous ignition. According to the tests, at the 48-hour storage, rapid increase in temperature ($178^{\circ}C$), Graphite phenomenon, smoking were observed. And the result from the DTA and DTG analysis showed that at $166.15^{\circ}C$, the minimum weight loss occurred. And, the result from the test on the waste tire analysis material 1 (Unburnt) through DSC and TGA analysis revealed that at $180^{\circ}C$ or so, thermal decomposition started. As a result, the starting temperature of ignition was considered to be $160^{\circ}C$ to $180^{\circ}C$. And, at $305^{\circ}C$, 10 % of the initial weight of the material reduced, and at $416.12^{\circ}C$, 50 % of the intial weight of the material decreased. The result from the test on oxidation and self-reaction through GC/MS and DSC analysis presented that oxidized components like 1,3 cyclopentnadiene were detected a lot. But according to the result from the heat analysis test on standard materials and fragmented waste tires, their heat value was lower than the basis value so that self-reaction was not found. Therefore, to prevent spontaneous ignition by oxidizing heat of waste tires, it is necessary to convert the conventional process into Cryogenic Process that has no or few heat accumulation at the time of fragmentation. And the current storing method in which broken and fragmented materials are stored into large burlap bags (500 kg) should be changed to the method in which they are stored into small burlap bags in order to prevent heat accumulation.

• Proceedings of the Technology Innovation Conference
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• 1997.07a
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• pp.222-223
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• 1997

By analyzing the successful innovation case of potato microtuber mass production technology, a representative case of technology-push type creative innovation in an imitation oriented research culture, this paper attempts to figure out conceptual model of creative innovation that is initiated by the public laboratories in catching-up country, Stages of creative innovation can be divided into the internal R&D stage and the external commercialization stage. Success of the internal R&D stage depended on autonomy to secure creative research idea and commitment of individual researchers. Psychological pressure evoked from sportlights of mass media and commitment of sponsor increased the intensity of research efforts of the researcher Recognition of research problem and its significance was intensified by site visits of agricultural fields, and the recognized higher impacts of expected research results and knowledge creation achieved were a fundamental source of self-motivation. In the stage of commercialization stage, various legal, socio-economic, and psychological barriers were confronted. In a catching-up country lacking of experiences of creative innovation, creative innovation process can be regarded as a barrier elimination and cultural revolution process. Among the barriers, psychological refusal of farmers to corn-sized potato seeds was critical, which finally enforced to further researches to enlarge the size of potato seeds. In addition, the researcher has concentrated his research efforts in one specialized research area by getting a series of similar research project funds rather than diversification. It was lucky for him to have a chance to carry out a series of similar researches in one research area during the last 10 years. In getting research funds from government and private companies continuously in one research area, both internal and external promoters played significant roles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.2
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• pp.11-26
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• 1964

The studies reported herein are on the varietal differences of rice in the effects of seeding times and nursery periods on the components such as, culm length, ear length, number of ears, ear weight, straw weight, and grain/straw ratio following the first series of studies on heading date. In the present investigations, 50 rice varieties, as the preceding studies, were seeded nine times at the interval of 15 days from March 15 to July 28 in 1963. Each variety seeded at respective time was transplanted in 40 days in nursery after seeded. Reviewing the result obtained from the first series of the studies on heading date, the number of days required to heading from seeding were decreased by delaying the seeding time. Most varieties tended to decrease in the number of days from seeding to heading by the 8th planting time. Some of varieties seemed to be decreased in the number of days from seeding to heading by 9th seeding time. However most varieties were failed to show heading delaying the seeding date at the 10th seeding. The results on the effects of altering the seeding time on the components and varietal differences of the response are summarized as follows; 1) Culm length; It appeared that culm length was shortened when the number of days from seeding to heading was decreased by delaying the seeding date. The varieties which needed many days to heading were also shortened in their culm length. 2) Ear length; Ear length was also shortened when the number of days needed tocheading was decreased, by delaying the seeding time. The varieties which needed many days for heading were also shortened in their ear length, while those which headed earlier seemed to be lengthened in their ear lengths. 3) Number of ears; It was shown that the number of ears was increased with the delay of the heading date, whereas, at the 9th seeding the number of ears was decreased when delayed the heading date. 4) Ear weight; Ear weight per hill was also likely to be heavy throughout the seeding times and varieties except the 7th and 8th seedings in which it appeared to be light on the contrary. 5) Straw weight; Straw weight became heavier as delayed the seeding date throughout all the varieties and seeding dates. 6) The grain/straw ratio; The grain/straw ratio was gradually increased by the 5th seeding time, reaching the pick at 5th. An examination of the varieties at each seeding date showed that the grain/straw ratio was low from 1st to 3rd seeding and from 7th to 9th seeding, when the number of days required to heading from seeding are increased. At the 4th seeding time-which is standard seeding time-5th, and 6th seeding times the ratio was high with the delay of heading.

• Journal of Home Health Care Nursing
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• v.4
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• pp.30-40
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• 1997

The change in health care environment increases the importance of Visiting Nursing Services Program. It has been performed by nurses of district health centers in Seoul since 1991. The Achievement of Visiting Nursing Services Program will be dependent upon their activities. The purpose of this study was to identify the Performance of Visiting Nurses and Job satisfaction of district health centers in Seoul. Therefore, it was to provide the fundamental data development of Visiting Nursing Services Program. The subjects were 214 Visiting Nurses of district health centers in Seoul. The data was collected by self reporting questionnaire from April 15 to April 30, 1997. Their performances and various supportive factors were measured with the instruments developed by the researcher. Job satisfaction were also measured by the instrument developed by Slavitt et al. (1978) was used. The data were, analyzed by Cronbach Alpha, mean, standard deviation, percentage, t -test, ANOVA Duncan test, Correlation Coefficient, and Stepwise Multiple Regression with SAS program. The results of this study were as follows: 1. The average of budget of Visiting Nursing Services Program of district health centers was 0.9% and the average of visiting nursing services personnel of district health centers was 10.1%. 2. With regard to the job satisfaction of Visiting Nurses the mean score was 2.92 out of 5. While the level of Job prestige / status presented as a mean score of 3.48 which was the largest among the 7 components of job satisfaction, the level of administration was the lowest showing 2.57 scores respectively. There were significant differences in the job satisfaction by age, working career of health centers(p<0.01, 0.001). 3. The average of the performance level of Visiting Nurses variables was 2.29; The variable with highest degree of performance was the teaching & consultation, establishment of performance plan, whereas the on with the lowest degree was the directive nursing services. The significant difference was found in performance level according to age, structure type of visiting nursing services, working career of health centers and working career of visiting nursing services(p<0.05). 4. With regard to the perception of the performance expertise by the Visiting Nurses the mean score was 2.37 : The variable with highest degree of performance expertise was the teaching & consultation, establishment of performance plan, whereas the on with the lowest degree was management of home-environment. The significant difference was found in performance expertise according to working career outside of health centers(p<0.05). 5. With regard to the perception of the performance necessity by the Visiting Nurses the mean was 2. 40 : the variable with highest degree of performance necessity was the teaching & consultation, establishment of performance plan, whereas the on with the lowest degree was directive nursing services. The significant difference was found in performance necessity according to working career of visiting nursing services(p<0.05). 6. A positive correlation was found between job satisfaction and performance level(r=.3731, P<0.001). Also, a weak positive correlation was found between the components of job satisfaction and performance level. 7. Stepwise multiple regression analysis revealed that the most powerful predictor was the variance of job satisfaction(R=.3557, $R^2$=.1265). Structure type of visiting nursing services and working career of visiting nursing services accounted for 19.0% of the variance in performance level in nurses. In conclusion, Job satisfaction, Structure type of visiting nursing services and Working career of visiting nursing services variables had influenced on performance level in health centers. Further research is required to confirm these findings.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.217-224
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• 1988

Changes in lipid components of Gul-bi, salted-dried yellow corvenia, during processing and storage were studied. Raw fishes contained $6.7\%$ total lipid (TL) which consisted of $83.3\%$ neutral lipid (NL), $6.5\%$ glycolipid (GL) and $10.2\%$ phospholipid (PL), and salted-dried sample at 30 days storage contained $11.1\%$ TL which consisted of $86.1\% NL, $7.1\%$ GL and $6.8\%$ PL. The NL was mainly consisted of trigly ceride (TG), free sterol (FS), free fatty acid (FFA), and the main lipids in PL were phosphatidyl choline (PC), phosphatidly ethanolamine (PE) and sphingomyelin (SPM). The contents of TG, PC, PE decreased, while that of FFA, SPM increased during processing and storage. Total fatty acid contents of raw fish, salted sample, salted-dried sample (product) and product at 30/days of storage were 847.9, 764.0, 633.5 and 588.mg/g-lipid, respectively, taking $C_{23:0}$ as the internal standard material. Most fatty acid con tents of TL revealed a tendency to decrease during processing and storage, highly unsaturated fatty acid such as $C_{22:6},\;C_{20:5}$, decreased largely. The major fatty acids in TL, NL, GL and PL were generally $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{20:5},\;C_{22:6}. Percentage of $C_{16:1},\;C_{18:1}$ in NL and GL and GL are higher than those in PL, while $C_{22:6},\;C_{20:5},\;C_{20:4}$. Peroxide value in salted-dried sample is 121.6 meq/kg and decreased rapidly with storage period, carbonyl value and brown pigment formation showed tendency of increase during processing and storage.