• Journal of Astronomy and Space Sciences
• /
• v.27 no.1
• /
• pp.55-68
• /
• 2010

It has been generally known that Datong-li (a Chinese calendar in the Ming dynasty) was first introduced into Korea in the nineteenth reign of King Gongmin (1370) of the Goryeo dynasty and lasted to the third reign of King Hyeojong (1652) of the Joseon dynasty. This understanding is based on the records of Goryeo-sa (History of the Goryeo dynasty) and of Seoungwan-ji (Official book of Seoungwan)/Jeungbomunheon-bigo (Explanatory Notes of Library Document). To verify the period of the use of Datong-li in Korea, we develop a Fortran code to calculate the calendar day by Datong-li and also investigate historical literatures and extant almanacs. As a result, we find the possibility that Datong-li had been in use since 1389 at least. However, we cannot confirm whether Datong-li was first enforced in 1370 or not. On the other hand, we confirm that Datong-li was used until 1653 and reintroduced during the period from 1667 to 1669. Also, we find that previous studies had some errors in the sexagenary cycle of the real first day of a month. We think that this study will contribute to understanding the calendrical history of the Joseon dynasty.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 1996.10b
• /
• pp.123-128
• /
• 1996

Bench Scale급 건식 가스화기에서 중국 Datong탄과 미국 Alaska Usibelli탄으로부터 생성된 Slag의 구조적인 특성과 화학적인 특성을 조사하였다. Datong slag은 표면이 매끄럽고 검으며 속이 약간 비어 있는 구형을 띄고 있고 Alaska Usibelli탄으로부터의 slag은 속이 조밀하게 차여있는데, 이들 slag의 내부는 Datong, Alaska Usibelli탄 두 경우 다 회분이 결정화된 형상의 특징을 보여주고 있다. 그리고 Cu, Zn외 11가지 중금속이 slag에 다량으로 농축되어 제거되었음을 알 수 있었으며, slag들의 침출여부를 조사하기 위하여 용출시험을 수행한 후 용출액에 대하여 중금속 분석을 한 결과 대부분 중금속들은 검출되지 않았다. 내화재의 주성분인 Cr이 slag에 포함되어 나오는 것으로 측정되었으나 용출시험 결과 검출이 안되어 2차오염에는 전혀 문제가 없음이 입증되었다. 따라서 건식 가스화기로부터 생성된 slag을 재사용할 때, 용출되는 중금속에 관한 2차 환경오염이 유발되지 않을 것으로 확인되었다.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.21 no.12
• /
• pp.1690-1700
• /
• 1997

Entrained coal gasification tests with Datong coal were performed to assess the influence of oxygen/coal ration and pressure. When gasification condition in oxygen/coal ratio has changed from 0.5 to 1.0, optimal gasification condition from low pressure runs was oxygen/coal ratio of approximately 0.9 where CO was produced about 40% and H, about 20%. Under the pressure condition of 12-14 atmospheres, optimal oxygen/coal ratio value was in the region of 0.6 where CO was produced about 55% and H2about 25%. From these results, it was found that the oxygen/ coal ratio for the maximum production of CO and H, was decreasing with the increase in gasifier pressure and also, with increasing oxygen content, carbon conversion was increased. For the Chinese Datong coal, cold gas efficiency was in the range of 40-80%.

• Journal of the Korean Mathematical Society
• /
• v.47 no.2
• /
• pp.385-407
• /
• 2010

To study the relationship between the levels of chemical pollutants and the number of daily total hospital admissions for respiratory diseases and to find the effect of temperature/relative humidity on the admission number, Wong et al. [17] introduced the varying-coefficient single-index model (VCSIM). As pointed out, it is a popular multivariate nonparametric fitting technique. However, the tests of the model have not been very well developed. In this paper, based on the estimators obtained by the local linear technique, the average method and the one-step back-fitting technique in the VCSIM, the generalized likelihood ratio (GLR) tests for varying-coefficient parts on the VCSIM are established. Under the null hypotheses the new proposed GLR tests follow the $\chi^2$-distribution asymptotically with scale constant and degree of freedom independent of the nuisance parameters, known as Wilks phenomenon. Simulations are conducted to evaluate the test procedure empirically. A real example is used to illustrate the performance of the testing approach.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.11a
• /
• pp.441-444
• /
• 2007

The inside wall of a coal gasifier is lined with refractory, and the corrosion of the refractory by coal sag is an important parameter affecting the refractory lifetime and the replacement period. This paper examines the changes in microstructure of a chromia refractory due to chemical reactions with penetrating slag as a function of slag composition. The effects of CaO and $Fe_2O_3$ concentrations were studied using Datong and KIDECO slag. Static corrosion experiments were carried out, the percent slag penetration and changes in the microstructure were determined by SEM/EDX analyses. FactSage equilibrium calculations were carried out to determine the equilibrium products and the predictions were compared with experimental observations.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2003.10b
• /
• pp.186-186
• /
• 2003

The aim of the study was to see if there is any differences in urinary 1-hydroxypyrene glucuronide (1-OHPG) levels in children (9-15 years old) living three cities in South Korea (Seoul, Incheon and Pohang) and three in China (Changchun, Datong and Kunming), where the levels of particulate air pollution varies.(omitted)

• Toxicological Research
• /
• v.23 no.1
• /
• pp.39-46
• /
• 2007

The aim of the study was to see if there is any differences in urinary 1-hydroxypyrene glucuronide (1-OHPG) and 2-naphthol levels in children ($8{\sim}14$ years old) and their mothers ($30{\sim}46$ years old) living three cities in South Korea (Seoul, Incheon and Pohang) and three in China (Changchun, Datong and Kunming), where the levels of air pollution varies. The factors related with urinary biomarkers levels were also evaluated. The study subjects consisted of 118 Korean (60 children and 58 their mothers) and 120 Chinese (60 children and 60 their mothers). Urinary 1-OHPG was measured by synchronous fluorescence spectroscopy after immuno-affinity purification using monoclonal antibody 8E11 and urinary 2-naphthol concentrations were determined by HPLC with fluorescence detector. Information on recent consumption of diet containing high PAHs, environmental tobacco smoke (ETS), type of cooking and heating fuels, and other life-style characteristics were collected by self-administered questionnaire. The arithmetic mean of urinary 1-OHPG levels (n = 120, $mean{\pm}SD$, $6.77{\pm}7.96{\mu}mol/mol$ creatinine) in Chinese were 10 fold higher than those in Korean (n = 118, $0.62{\pm}0.61{\mu}mol/mol$ creatinine) (P < 0.01). Urinary 2-naphthol levels in Chinese (n = 119, $59.50{\pm}82.29{\mu}g/g$ creatinine) were significantly higher than those in Korean (n = 117, $25.09{\pm}46.56{\mu}g/g$ creatinine) (P < 0.01). Urinary 1-OHPG and 2-naphthol levels were significantly higher in children living the polluted cities in China (Datong and Chanchun, respectively). Multiple linear regression analysis indicated that living in factory area (vs. residential area) and use of coal stove as heating fuel were significant predictors for urinary 1-OHPG (overall model $R^2$= 0.46, n = 204). And ETS was predictor for urinary 2-naphthol levels in Korean ($R^2$ = 0.36, n = 46). These results indicated that urinary 1-OHPG and 2-naphthol levels were related with different ambient particulate air pollution, type of heating fuels and ETS.

• The Journal of the Korea Contents Association
• /
• v.18 no.4
• /
• pp.154-163
• /
• 2018

The research object is Huayan Street, which is located in Datong City of Shanxi Province in Northern China. And it's detailedly seated to the east of the Huayan Temple. This street is a multicultural area which covers religious and business culture, along with other kinds of civilization since ancient time. The purpose of this research is to restore the historical and cultural tradition, improving the economic development. This research will use the theory of narrative to analyze the public design of Huayan Street. It's present the new design concept to reflect the cultural story of this region. First of all, the cultural stories of Huayan Street were explored and collected by introducing the history. Secondly, the drawbacks of public design of this street were found out by analyzing the current situation in Huayan Street At the end of this paper, a design solution was proposed according to the history and culture with story-telling methods from narratology which depart the street into four scenes opening, developing, changing and concluding. The innovation point of this research is apply humanism into the public design of Huayan Street and rebuild the image of Huayan Street.

• Journal of Energy Engineering
• /
• v.6 no.1
• /
• pp.96-103
• /
• 1997

Coal gasification experiments were performed to characterize the bench scaled unit of 0.5∼1.0 T/D entrained coal gasifier developed by KIER. Datong coal from China was selected for this study. The system was operated at the temperature range of 1300∼1550$^{\circ}C$, with 62.5% of coal water mixture on the basis of dry coal. Oxygen and slurry mixture were preheated prior to feeding into burner and the ratio of oxygen/coal was in the range of 0.8∼1.2. In the preparation of coal water mixture, 0.3 wt% of CWM1002 and 0.05 wt% of NaOH wire added to reduce viscosity as well as to enhance theological properties of slurry. The resultant gaseous products consist primarily of hydrogen, carbon monoxide, carbon dioxide, and minor amounts of methane. Formation of H$_2$and CO was increased, while CO$_2$was decreased as the reacting temperature being increased due to the char-CO$_2$reaction. Maximum production of H$_2$and CO occurred in the O$_2$/coal ratio of 0.9 at 1530$^{\circ}C$. Heating values of product gases were in the range of 1700∼2400 kcal/N㎥.

• Animal Bioscience
• /
• v.36 no.7
• /
• pp.1022-1033
• /
• 2023

Objective: p66Shc, a 66 kDa protein isoform encoded by the proto-oncogene SHC, is an essential intracellular redox homeostasis regulatory enzyme that is involved in the regulation of cellular oxidative stress, apoptosis induction and the occurrence of multiple age-related diseases. This study investigated the expression profile and functional characteristics of p66Shc during preimplantation embryo development in sheep. Methods: The expression pattern of p66Shc during preimplantation embryo development in sheep at the mRNA and protein levels were studied by quantitative real-time polymerase chain reaction (RT-qPCR) and immunofluorescence staining. The effect of p66Shc knockdown on the developmental potential were evaluated by cleavage rate, morula rate and blastocyst rate. The effect of p66Shc deficiency on reactive oxygen species (ROS) production, DNA oxidative damage and the expression of antioxidant enzymes (e.g., catalase and manganese superoxide dismutase [MnSOD]) were also investigated by immunofluorescence staining. Results: Our results showed that p66Shc mRNA and protein were expressed in all stages of sheep early embryos and that p66Shc mRNA was significantly downregulated in the 4-to 8-cell stage (p<0.05) and significantly upregulated in the morula and blastocyst stages after embryonic genome activation (EGA) (p<0.05). Immunofluorescence staining showed that the p66Shc protein was mainly located in the peripheral region of the blastomere cytoplasm at different stages of preimplantation embryonic development. Notably, serine (Ser36)-phosphorylated p66Shc localized only in the cytoplasm during the 2- to 8-cell stage prior to EGA, while phosphorylated (Ser36) p66Shc localized not only in the cytoplasm but also predominantly in the nucleus after EGA. RNAi-mediated silencing of p66Shc via microinjection of p66Shc siRNA into sheep zygotes resulted in significant decreases in p66Shc mRNA and protein levels (p<0.05). Knockdown of p66Shc resulted in significant declines in the levels of intracellular ROS (p<0.05) and the DNA damage marker 8-hydroxy2'-deoxyguanosine (p<0.05), markedly increased MnSOD levels (p<0.05) and resulted in a tendency to develop to the morula stage. Conclusion: These results indicate that p66Shc is involved in the metabolic regulation of ROS production and DNA oxidative damage during sheep early embryonic development.