• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.12
• /
• pp.1909-1915
• /
• 2010

The material properties of gas turbine components change during the daily start/stop thermal cycle because of exposure to the hot combustion gas. Recently, single-crystal Ni-based superalloys have been used to manufacture many hot-gas components for gas turbines. However, the user needs to depend on the manufacturer for maintenance issues because of the lack of data required for predicting blade life and material degradation. In this study, we investigate the time-dependent degradation of first-stage blades at various operating facilities to collect the basic data for life assessment and damage analysis. The blade material is a single-crystal Ni-based superalloy, CMSX-4, and the EOH (equivalent operating hours) are 25,000 and 52,000, respectively. We prepared the test specimen directly from used blades and carried out mechanical tests and microstructural observations.

• Journal of Korean Society of Transportation
• /
• v.29 no.6
• /
• pp.85-93
• /
• 2011

The width of sidewalk is one of the important factors constructing a pleasant pedestrian environment. The procedure for sidewalk width design based on the Level of Service is suggested in Korea Highway Capacity Manual. However, this manual does not give a difference between the sidewalk on the street with the passage of the subway, therefore, the different flow characteristic of these places is not appropriately reflected. Though the pedestrian flow in the subway encounters a frequent stop and go situation as like the platoon of vehicles, the similar condition is rarely observed at the urban streets. The new measure of LOS for sidewalk is in need. The study reviewed the prominent measure of LOS and carried out the outdoor experiment to evaluate the new measure. Particularity, GPS was used to collect the pedestrian foot path trajectory for the quantitative evaluation and the results from quantitative and qualitative are compared.

• Microbiology and Biotechnology Letters
• /
• v.28 no.1
• /
• pp.8-13
• /
• 2000

A study was carried out to determine the probiotic effect of Lactobacillus reuteri BSA-131 by investigating the growth performance and fecal microbial population of piglets. Five dietary treatment groups, the basal diet (control, BD), basal diet with antibiotics(BA), basal diet with 2$\times$106/g of probiotics (BP6), 2$\times$108/g of probiotics (BP8) and basal diet with antibiotics and 2$\times$108/g probiot-ics(BAP8) were divised. Each dietary treatment group was consisted of 1 month of age piglets(male 13, female 12). Fecal micro-flora, body weights and feed consumption were measured at before, after and stop feeding of probiotics. The results showed that the CFU of fecal Enterobacteriaceae of piglets of the group BA, BP6, BP8 and BAP8, were reduced (P<0.05) compared to control BA. On the contrary, Lactobacillus counts were increased significan시 (P<0.001) in all groups fed probiotics dites, but not antibiotics. Body weight of probiotics treated piglets were improved 5% (p<0.001) in BP6 group than that of control group and antibiotic treated piglets BAP group was 27% (P<0.001) higher than BA group. The amount of feed consumption value of probiotics treated piglets showed 21-30% (P<0.001) lower intake than the control group, whereas antibiotic treated piglets BAP was 20% (P<0.001) higher than BA group. The results showed that body weights and feed to gain ratios were improves 19% when compared to control piglets for groups fed diets probiotic. It is very suggestive that productivity of probiotic piglets would be economical in pig farming.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.10
• /
• pp.1800-1807
• /
• 2016

To understand how human cytomegalovirus (HCMV) might change and evolve after reactivation, it is very important to understand how the nucleotide sequence of cultured HCMV changes after in vitro passaging in cell culture, and how these changes affect the genome of HCMV and the consequent variation in amino acid sequence. Strain JHC of HCMV was propagated in vitro for more than 40 passages and its biological and genetic changes were monitored. For each passage, real-time PCR was performed in order to determine the genome copy number, and a plaque assay was employed to get virus infection titers. The infectious virus titers gradually increased with passaging in cell culture, whereas the number of virus genome copies remained relatively unchanged. A linear correlation was observed between the passage number and the log₁₀ infectious virus titer per virus genome copy number. To understand the genetic basis underlying the increase in HCMV infectivity with increasing passage, the whole-genome DNA sequence of the high-passage strain was determined and compared with the genome sequence of the low-passage strain. Out of 100 mutations found in the high-passage strain, only two were located in an open reading frame. A G-T substitution in the RL13 gene resulted in a nonsense mutation and caused an early stop. A G-A substitution in the UL122 gene generated an S-F nonsynonymous mutation. The mutations in the RL13 and UL122 genes might be related to the increase in virus infectivity, although the role of the mutations found in noncoding regions could not be excluded.

• Archives of design research
• /
• v.15 no.4
• /
• pp.379-390
• /
• 2002

Science Revolution, which stands for new paradigm in an era as a transfer, usually is accompanied with a change in intellectual sphere. Futhermore, as there is an indissoluble connection between science and an, so the correlation of two realm lead to mutual prosperity in coexistence. Recently, concerns for the phenomena of non-linear dynamics in science and its quick adaptation in art made .it possible. What is important agenda for science and art is to suggest the process of creative evolution and its method, I believe. In order to attain these, different and contra way of thinking, spirit of research and venture for unpredictable things out of daily routine should be indispensible. In this study, I am offering and reviewing the space design based upon phenomena of nonlinear dynamics, drawn from concept of chaos in physics and mathematics. This study places a great emphasis on nonlinearity which should be understood as a whole, not partially, that enable a designer to find new cosmos and principles of creation. In addition to these, I wish that a designer would stop trying partial apply in nonlinear space. In fine, I hope this study enables a designer to adapt and generate nonlinearity as creative attribute in space by understanding of phenomena of nonlinear dynamics and its process as a whole.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.10 no.2
• /
• pp.55-60
• /
• 2010

The purpose of this study is to analyze compact city planning indicators that have influence on public transportation commuting of residents in the 54 medium and small-sized cities. In the study, land use and transportation infrastructure of cities and other socio-demographic variables are used as explanatory variables in a causal model. 96,552 subjects from 54 cities in korea are selected as the final sample, and a statistical analysis is carried out by applying Random Intercept Logit Model. Analysis shows that a high level of density and jobs-housing balance in the city results in more public transportation commuting. And higher access to bus and subway station influence commuting, so subway & bus stop are important factors to increase public transportation commuting

• Journal of Korean Medical classics
• /
• v.18 no.1 s.28
• /
• pp.146-174
• /
• 2005

This study analyzes a medicine and iching-study(易學) and vital meaning through a me야cal science ruler called ZhangNan(章楠) of Qing-Dynasty(淸代), but has a purpose. First of all, the writer judges that the ZhangNan's medicine did not get out of a tradition of a Rui-Yi(儒醫, Confucian medicine) medicine greatly. He considered philosophy character of Rui-Yi formed after Jin-Yuan Dynsty(金元代) a purpose of own medicine. A way he kept the human life in order to realize a large meaning of Confucianism, and to stop a disease was necessary and spoke necessity of a medicine for this. Though a medicine is small, but becomes necessary thing in order to realize Confucianism whether a medicine and Confucianism are the only each other. The ZhangNan presented Zhi-zhong-he(致中和) with a way as soon as it is a purpose of a medicine, but ZhangNan is opening the point that Xing(性) was given 'Taiji(太極)'to. If Neo-Confucianism named 'Taiji(太極)-xing(性)-li(理)' is general, but ZhangNan is introducing the Taiji with Chi(氣). ZhangNan introduces the Taiji(太極) with one Chi(氣) and is rea야ng thing with another Zhu-zai(主宰) except Taiji, but cannot but recognize this with one in characteristics of a medicine ruler. A disregard is the inferior results, and this can do entrance of the Huang-di-nei-jing(業帝內經) which put a base with Han-Dynasty(漢代) iching-study(易學) and this too. It is made concrete 'Zangfu(藏府)-Taiji', and he is considering 'Dan-tian(丹田)-Taiji‘ in a discussion about the Great Absolute to be physical too more. Also, Taiji' is describing a point of contact that a spirit and the body meet with.

• Membrane Journal
• /
• v.25 no.1
• /
• pp.7-14
• /
• 2015

In this study transmembrane pressure (TMP) was measured with respect to operational time in order to estimate fouling of the submerged membrane in the membrane bioreactor(MBR). The microfiltration flat sheet module which has $0.02m^2$ of effective area and $0.15{\mu}m$ nominal pore size was submerged in the activated sludge solution of MLSS 5,000 mg/L. The permeate experiments were carried out simultaneously to compare TMP of the run/stop (R/S) with that of the sinusoidal flux continuous operation (SFCO). TMP for SFCO mode was up to 93% lower than that of R/S mode, and the effect of TMP drop reduced as permeate flux increased. Also, TMP of the SCFO mode was maintained below 40% of the limited operating TMP 55 kPa until the permeate operational time extended to longer than 5 times for the case as the coagulant $FeCl_3$ was dosed into the activated sludge solution with 500 mg/L concentration.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.11
• /
• pp.4497-4502
• /
• 2015

Background: Due to the increase in morbidity and mortality rate, cancer has become an alarming threat to the human population worldwide. Since cancer is a progressive disorder, timely diagnosis would be helpful to prevent/stop cancer from progressing to severe stage. In Khyber Pakhtunkhwa, Pakistan, most of the time, tumors are diagnosed with endoscopy and biopsy; therefore rare studies exist regarding the diagnosis of gastrointestinal (GIT) carcinomas based on tumor markers, especially CEA. Objectives: This study made a comparative analysis of CEA in admitted hospitalized stomach and colon cancer patients diagnosed as GIT with biopsy. Materials and Methods: In this study, a total of 66 cases were included. The level of CEA was determined in the blood of these patients using ELISA technique. Results: Out of 66 patients, the level of CEA was high in 59.1% of the total, 60.7% in colon cancer patients and 57.9 % in stomach cancer patients. Moreover, the incidence of colorectal and stomach cancer was greater in males as compared to females. Patients were more of the age group of 40-60 and the level of CEA was comparatively higher in patients (51.5%) with histology which was moderately differentiated, than patients with well differentiated and poorly differentiated tumor histology. Conclusions: CEA level was high in more than 50% of the total patients. Moreover, CEA exhibited higher sensitivity for colon than stomach cancer.

• The Journal of Korean Institute for Practical Engineering Education
• /
• v.4 no.1
• /
• pp.140-145
• /
• 2012

Korean government improved the Individual Training Account (ITA) System in September 15, 2011. This paper evaluated the Improved Individual Training Account System of Korea based on the success conditions of contracting-out public services. The results showed that the improved ITA system of Korea was expected to solve some of the problems of former ITA system of Korea by stabilizing ITA training market, improving target of ITA and better matching between jobs and training courses, and activating trainees. Nevertheless the improved ITA system of Korea still has some problems to be solved. The relationship between job placement services and issue of ITA should be closer by improving tailored total one-stop services for job seekers. The government should develop infrastructure for evaluating, monitoring and supporting the ITA training to enhance the effectiveness and efficiency of the ITA training system.