• 제목/요약/키워드: Secular Change

검색결과 52건 처리시간 0.028초

A Monitoring Observation of Comet 17P/Holmes during 2014 Apparition

  • Kwon, Yuna;Ishiguro, Masateru;Hanayama, Hidekazu;Kuroda, Daisuke;Sarugaku, Yuki;Kim, Yoonyoung;Vaubaillon, Jeremie J.;Takahashi, Jun;Watanabe, Jun-Ichi
    • 천문학회보
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    • 제40권1호
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    • pp.61.1-61.1
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    • 2015
  • We performed a monitoring campaign of a Jupiter-Family comet 17P/Holmes, which underwent the dramatic outburst on 23.3 October 2007 at $r_h=2.44AU$, to investigate the secular change in activity and subsequent physical properties of the inner dust coma before and after the 2014 perihelion passage. The monitoring observation was carried out over two years: from May to July 2013, from July to November 2014, and January 2015 with ~weekly cadence. We conducted photometry monitoring in Rc band using four ground-based telescopes, which are the Ishigakijima Astronomical Observatory 105cm telescope, the Okayama Astrophysical Observatory 50cm telescope, the Nishi-Harima Astronomical Observatory 2m telescope, and the T30 51cm i-telescope, respectively. In order to examine the dust production rate, we put a constraint upon the physical distance from the center of the nucleus as rho=2500km and conducted aperture photometry. We found that the average absolute Rc magnitude over the period between July to November 2014 was mR(1,1,0)~12.29, which was approximately 1.5 magnitudes fainter than those of 2013 data. Accordingly, comet 17P/Holmes seemed to become dormant, although a minor eruption was detected on January 26, 2015. In this presentation, we will introduce our ongoing project for 17P/Holmes and discuss why the nucleus becomes dormant within one orbital period.

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Time Trends of Nasopharyngeal Carcinoma in Urban Guangzhou over a 12-Year Period (2000-2011): Declines in Both Incidence and Mortality

  • Li, Ke;Lin, Guo-Zhen;Shen, Ji-Chuan;Zhou, Qin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권22호
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    • pp.9899-9903
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    • 2014
  • Nasopharyngeal carcinoma (NPC) is an uncommon disease in most countries but occurs with much greater frequency in southern China. This study aimed to examine the secular trends of NPC in urban Guangzhou over the time period of 2000-2011 using data from the Guangzhou Cancer Registry. Age-adjusted annual incidence rates of NPC were calculated by the direct method using the WHO World Standard Population (1960) as the reference. The average annual percentage change (AAPC) was used as an estimate of the trend. A total of 7,532 new cases of NPC and 3,449 related deaths were registered. In both genders, the peak incidence occurred in the 50- to 59-year age group, and this age distribution pattern remained similar throughout. The AAPC in NPC incidence rates was -3.26% (95% CI: -5.4%--1.1) for males and -5.74% (95% CI: -8.9%--2.5) for females, resulting in a total decrease of 39.3% (from 22.14 to 13.44 per 100,000 population) for males and 48.6% (from 10.1 to 5.18 per 100,000 population) for females over this 12-year period. The AAPCs in NPC mortality rates were -4.62% (95%CI: -3.5%--5.7) for males and -6.75% (95% CI: -5.2%--8.3) for females, resulting in a total decrease of -46.1% (from 12.1 to 6.54 per 100,000 population) for males and 51.7% (from 4.14 to 2.00 per 100,000 population) for females. The age-adjusted incidence and mortality rates of NPC declined during 2000-2011 in urban Guangzhou but remained high. Future efforts to improve prevention, early detection and treatment strategies are needed.

Variation in Meal-skipping Rates of Korean Adolescents According to Socio-economic Status: Results of the Korea Youth Risk Behavior Web-based Survey

  • Hong, Seri;Bae, Hong Chul;Kim, Hyun Soo;Park, Eun-Cheol
    • Journal of Preventive Medicine and Public Health
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    • 제47권3호
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    • pp.158-168
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    • 2014
  • Objectives: To identify and evaluate the trend of meal-skipping rates among Korean adolescents with their contributing causes and the influence of household income level on meal skipping. Methods: Using 2008, 2010, and 2012 data from the Korea Youth Risk Behavior Web-based Survey of 222 662 students, a cross-sectional study with subgroup analysis was performed. We calculated odds ratios for skipping each meal 5 or more times in a week by household socio-economic status using a multiple logistic regression model. The secular change in the meal-skipping rates by the students' family affluence scale was analyzed by comparing the meal-skipping students within each subgroup and odds ratios for the same event over time. Results: Through 2008 to 2012, most of the meal-skipping rates generally showed a continuous increase or were almost unchanged in both sexes, except for breakfast skipping in several subgroups. Students in low-income households not living with both parents had the highest meal-skipping rates and odds ratios for frequent meal skipping. In a time-series subgroup analysis, the overall odds ratios for the same event increased during 2008 to 2012, with a slight reduction in the gap between low and higher income levels with regard to meal skipping during 2010 to 2012. Conclusions: Household socio-economic status and several other factors had a significant influence on Korean adolescent meal-skipping rates. Although the gap in eating behavior associated with household socio-economic differences is currently decreasing, further study and appropriate interventions are needed.

일본 UR도시기구의 안심주공간사업자참여제도를 통한 지역복지거점시설 정비사례 연구 (A Case Study on the Local-based Welfare Facilities of Urban Renaissance Agency in Japan by Business Entry System for Stable Living)

  • 유순선
    • 한국주거학회논문집
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    • 제24권5호
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    • pp.9-16
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    • 2013
  • The purpose of this study is to analyze local-based social welfare facilities to respond to secular change of the UR rental housing estates in Japan. The selected case studies for the analysis are Hibarigaoka, Hamakousien, Turumai UR rental housing estates constructed around 1960's. The analysis was done through UR website, MLIT (Ministry of Land, Infrastructure, Transport and Tourism) and MHLW (Ministry of Health, Labour and Welfare) policy report, and related literature. These case studies are connected with housing policy as well as welfare policy and performed to Stable Living Creation Project by Business Entry System for Stable Living. The types of local-based social welfare facilities are classified by welfare corporation and medical corporation. The results are as follows: 1) The implementation of cooperative and participative system not only the private sector (welfare and medical Corporation, etc.) but also the public (MLIT, MHLW, UR Renaissance Agency, Local government, etc.). 2) Repurposed of land through rent and transfer of land for local-based social welfare facilities in the process of housing stock renewal utilization. 3) The pursue of regional revitalization through attached to multi-generation facility or local community space for elderly in local-based social welfare facilities.

Secular Trends of Species and Antimicrobial Resistance of Blood Isolates in a Tertiary Medical Center for Ten Years: 2003~2012

  • Shin, Kyeong Seob;Son, Young Il;Kim, Yong Dae;Hong, Seung Bok;Park, Je-Seop;Kim, Sunghyun;Yu, Young-Bin;Kim, Young Kwon
    • 대한의생명과학회지
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    • 제20권2호
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    • pp.77-84
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    • 2014
  • Periodic analysis of local epidemiologic data of prevalent pathogens of blood culture can provide clinicians with relevant information to guide empirical antibiotic therapy. In this study, we analyzed a pattern of change of causative microorganisms and antimicrobial resistance at a tertiary medical center in Chungcheong province from 2003 to 2012, retrospectively. Of 70,258 blood specimens cultured, 6,063 (8.6%) were positive. Among the positive isolates, 95.9% were aerobic or facultative anaerobic bacteria, 0.1% were anaerobes, and 3.9% were fungi. Coagulase-negative Staphylococci (CoNS) (32.9%), Escherichia coli (16.7%), Staphylococcus aureus (9.1%), Klebsiella pneumoniae (6.4%), and ${\alpha}$-hemolytic Streptococcus (5.9%) were commonly isolated bacteria, and Candida albicans (1.4%) was the most commonly isolated fungi. Enterococcus faecium progressively increased but Streptococcus pneumoniae, Acinetobacter baumannii and Proteus species gradually decreased over a period of 10 years. The multidrug-resistant microorganisms such as methicillin-resistant S. aureus (MRSA), vancomycin-resistant enterococci (VRE), cefotaxime-resistant E. coli, imipenem-resistant Pseudomonas aeruginosa (IRPA) and imipenem-resistant A. baumannii (IRAB), were significantly increased. Therefore, there is a need for a more strict control of antibiotics and a more updated guideline for the treatment of bloodstream infection.

한국 전통사찰의 인공지 연구 (A Study on the Ponds of the Korean Traditional Temples)

  • 권태철;홍광표
    • 한국조경학회지
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    • 제27권2호
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    • pp.80-94
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    • 1999
  • The purpose of this study is to analyze and interpret the ponds appeared in the Korean traditional temples. Summarized findings are as follows: First, it appeared that the location of ponds of the Korean traditional temples is, in general, in both the entry space and transitional space of temple. And it is considered that such configurations of the location of ponds were done intentionally in order that the ponds should have a significance as same as the concept that a natural mountain stream separates the sacred place and the secular world. Second, since the size of the ponds appeared in the temples are considered to be what is transformed from the original one, it is hard to understand the real size. However, it is judged that since ponds we see at present played an element of the total space of a temple it is deemed that no significant change of the size of ponds have happened if the size of the structure a temple itself has ever changed. Third, it appeared that the forms of the temple's ponds are diversified in a square, oval, egg-shaped one, round shape(circle), natural shape, etc. and it is identified that most of the ponds inspected for this study appeared to be in shapes of an oval, egg-shaped one, and round shape which take a typical curve. Fourth, regarding the temples whose origins are from the Baekje dynasty or Shilla dynasty among the objects of this case study, there appear some uniform styles for each temple respectively. For example, in both the Junglim Temple's twin pond(定林寺 雙池) and the Mireuk Temple's twin pond(彌勒寺 雙池) which were built in the Baekje dynasty appears a twin-pond in a square shape, and in the Bulkuk temple(佛國寺), Haein temple(海印寺), Tongdo temple(通度寺), etc. which were built in the Silla dynasty appears the ponds in an egg-shape one. Fifth, regarding the function of the ponds appeared in the temples, the ponds are characterized with a lotus pond(蓮池), reflecting pond(影池), and pond complex(蓮 . 影池). In consideration of the 20 ponds in the 15 places of this study's object, there are 8 lotus ponds(蓮池), 6 reflecting ponds(影池), and 6 ponds complex(蓮 . 影池).

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하천 및 녹지와 온도의 관계에 대한 기초적 연구 - 청계천 복원을 중심으로 - (A Fundamental Study on the Relationship Between Riparian Vegetation and Surface Temperature - Focused on Cheonggaecheon Stream Restoration -)

  • 김재욱;이동근;오규식;성현찬
    • 한국환경복원기술학회지
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    • 제6권3호
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    • pp.79-85
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    • 2003
  • Human beings have pursued development and economic betterment; thus, enhancing convenience and prosperity. A flourish of human civilization upon the industrialization results a massive urbanization. However, human beings have connived the environmental importance in the course of rapid urbanization. The environmental quality now becomes one of the most important factors that determine the quality of life in a city. Many studies were proceeded about the heat island effect in large cities. In general, most studies have been done to investigate urban microclimate phenomena using meteorological network or AWS (automatic weather station) data. Those preceding studies do not seem to sufficiently reflect the and thus, failed to show regional representative. In this study, temporal Landsat TM satellite imageries of May 20, 1987 and May 21, 1999 were 뻐d in order to detect the surface temperature of the study area using the band 6 ($10.4{\mu}m{\sim}12.5{\mu}m$). The surface temperature distribution detected by the band 6 of Landsat TM was over layed with the land cover classification data in order to investigate the temperature difference of the paved road and the riparian areas of the stream. As a result, a surface temperature difference as much as $3^{\circ}C$ between the paved road and the riparian areas with vegetation was observed. This study concludes that the land cover change is one of the main causes of urban heat island effect which may be closely affected by the paved areas and roads. Besides, the change of the atmospheric temperature followed by the urban secular change could have been confirmed. In the case of Yangjaecheon stream which underwent a heavy environmental restoration in 1995, the temperature was decreased as much as $0.6^{\circ}C$ after the restoration. The results of this study is expected to contribute to develop an urban space in harmony with the healthy human life and the environment respecting the crucial role of vegetation to stabilize the urban environmental dynamics.

대학생기독교선교회 시니어간사의 경력전환 경험 탐색 (Exploring the Meanings of Career Transition Experience of Senior Stewards of the Campus Crusade for Christ)

  • 신봉진;유기웅
    • 한국콘텐츠학회논문지
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    • 제18권10호
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    • pp.247-256
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    • 2018
  • 본 연구는 세속 직업에 종사하다가 대학생 선교단체 간사로 경력을 전환한 대학생 선교단체 간사의 경력전환 과정과 경험을 탐색하는 것을 목적으로 한다. 연구목적을 달성하기 위하여 한국대학생선교회(CCC)에 소속되어 있는 시니어간사 5명을 인터뷰하여 분석하였다. 주요 연구결과는 다음과 같다. 첫째, 대학생 기독선교회 시니어 간사의 경력전환 동기는 소명의식과 유관함을 알 수 있다. 둘째, 경력전환 과정에서 새로운 환경에 대한 적응과 주위로 부터의 격려와 지지를 경험하는 것으로 나타났다. 셋째, 간사의 경력전환의 의미는 하고자 했던 일을 다시 찾게 됨과 약속지킴, 특별하고 영광스러운 삶인 것으로 나타났다. 이상의 연구결과를 토대로 다음과 같은 결론을 얻었다. 첫째, 선교단체 간사의 소명실행은 소명확인의 단계가 필수적임을 확인할 수 있었다. 둘째, 선교단체 간사의 소명실행은 주위 지지자들이 있을 때 더욱 지속됨을 알 수 있었다. 셋째, 선교단체 간사의 경력전환경험이 갖는 의미는 소명을 따라가는 삶에 있음을 알 수 있었다.

Change in the height of Korean children and adolescents: analysis from the Korea National Health and Nutrition Survey II and V

  • Ryoo, Na Yung;Shin, Ha Young;Kim, Jae Hyun;Moon, Jin Soo;Lee, Chong Guk
    • Clinical and Experimental Pediatrics
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    • 제58권9호
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    • pp.336-340
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    • 2015
  • Purpose: The mean adult height of Koreans has increased since nationwide anthropological measurements began in 1967. The objective of this study was to evaluate differences in heights of Korean late adolescents and young adults within and between the Second and Fifth Korea National Health and Nutrition Examination Surveys (KNHANES II and V). Methods: Koreans aged ${\leq}22$ years with available measurements of height were enrolled from the KNHANES surveys (KNHANES II: n=3,372 [1,732 males and 1,640 females]; KNHANES V: n=6,190 [3,198 males and 2,992 females]). Differences in the height of KNHANES respondents within and between surveys were evaluated according to age and sex. Results: In KNHANES II, there was no significant difference in height between males aged 17-19 years and those aged 20-22 years ($174.3{\pm}0.5cm$ vs. $174.3{\pm}0.6cm$, P=0.995). Females aged 20-22 years were taller than those aged 17-19 years ($159.8{\pm}0.4cm$ vs. $161.0{\pm}0.4cm$, P=0.017). Females aged 17-19 years were significantly taller in KNHANES V than in KNHANES II ($161.2{\pm}0.3cm$ vs. $159.8{\pm}0.4cm$, P=0.004). Respondents aged 20-22 years were taller in KNHANES V than in KNHANES II, although not significantly so; the difference was $0.3{\pm}0.8cm$ in males (P=0.721) and $0.5{\pm}0.6cm$ in females (P=0.386). Conclusion: Koreans appear to continue growing even in their late adolescence and early twenties. Consequently, it may be necessary to expand the reference age ranges of the Korean growth chart. Additionally, a longitudinal growth survey is needed to determine growth patterns and secular trend in height among Koreans.

근접촉쌍성 XZ CMi의 CCD 측광관측과 광도곡선 분석 (CCD Photometric Observations and Light Curve Synthesis of the Near-Contact Binary XZ Canis Minoris)

  • 김천휘;박장호;이재우;정장해;오준영
    • Journal of Astronomy and Space Sciences
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    • 제26권2호
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    • pp.141-156
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    • 2009
  • 근접촉쌍성 XZ CMi의 BV 측광관측을 수행하여 새로운 광도곡선과 총 7개의 극심시각을 획득하였다. 관측한 극심시각과 지금까지 발표된 극심시각을 수집하여 XZ CMi의 궤도 공전주기를 분석한 결과, 이 쌍성계의 공전주기가 지난 70년간 영년 주기감소와 더불어 규칙적으로 변화함을 확인하였다. 규칙적인 변화를 제3천체에 의한 광시간 효과로 가정하여 0.0056일의 진폭, 약 29년의 주기, 그리고 0.71의 궤도이심율의 광시간 궤도를 결정하였다. 관측된 영년 주기감소($-5.26{\times}10^{-11}d/P$)를 자기제동 항성풍의 각운동량 손실에 의한 주기감소($-8.20{\times}10^{-11}d/P$)와 질량이 작은 반성에서 주성으로 질량 이동에 의한 주기 증가($2.94{\times}10^{-11}d/P$)가 동시에 일어나는 것으로 해석하였다. 이런 관점에서 AML에 의한 주기감소율은 질량 이동에 의한 공전주기 증가율보다 그 크기가 약 3배 정도 크며, 반성에서 년간 $3.21{\times}10^{-8}M_{\odot}$의 질량이 주성으로 이동된다. 관측된 BV 광도곡선을 최근의 Wilson & Devinney 쌍성코드로 주성의 온도를 달리하는 두가지 모형(8200K와 7000K)을 상정하여 분석하였다. 두가지 모형 해 모두 XZ CMi가 반성이 로쉬 로브를 채웠으나, 주성은 아직 로쉬 로브를 채우지 않은 근접촉 쌍성임과 약 15-17%의 제3광도가 이 계에 있음을 보여준다. 그러나, 제3광도를 내는 천체가 주기연구에서 제안한 제3천체와 동일 천체가 아닌 것은 확실하다. 두 모형의 $\sum(O-C)^2$의 차이는 너무 미미하여, 현 시점에서 어느 해가 더 관측치를 잘 맞추는 지를 가릴 수는 없었다. 그간 연구자간에 불일치하였던 질량비의 다양성 문제는 아직도 풀리지 않는 숙제로 남아있다. 이를 해결하기 위해서 분광시선속도곡선과 스펙트럼의 관측과 더불어 정밀 측광관측이 필요하다.