• Title/Summary/Keyword: Temporal trends

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Global Temperature Trends of Lower Stratosphere Derived from the Microwave Satellite Observations and GCM Reanalyses (마이크로파 위성관측과 모델 재분석에서 조사된 전지구에 대한 하부 성층권 온도의 추세)

  • Yoo, Jung-Moon;Yoon, Sun-Kyung;Kim, Kyu-Myong
    • Journal of the Korean earth science society
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    • v.22 no.5
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    • pp.388-404
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    • 2001
  • In order to examine the relative accuracy of satellite observations and model reanalyses about lower stratospheric temperature trends, two satellite-observed Microwave Sounding Unit (MSU) channel 4 (Ch 4) brightness temperature data and two GCM (ECMWF and GEOS) reanalyses during 1981${\sim}$1993 have been intercompared with the regression analysis of time series. The satellite data for the period of 1980${\sim}$1999 are MSU4 at nadir direction and SC4 at multiple scans, respectively, derived in this study and Spencer and Christy (1993). The MSU4 temperature over the globe during the above period shows the cooling trend of -0.35 K/decade, and the cooling over the global ocean is 1.2 times as much as that over the land. Lower stratospheric temperatures during the common period (1981${\sim}$1993) globally show the cooling in MSU4 (-0.14 K/decade), SC4 (-0.42 K/decade) and GEOS (-0.15 K/decade) which have strong annual cycles. However, ECMWF shows a little warming and weak annual cycle. The 95% confidence intervals of the lower stratospheric temperature trends are greater than those of midtropospheric (channel 2) trends, indicating less confidence in Ch 4. The lapse rate in the trend between the above two atmospheric layers is largest over the northern hemispheric land. MSU4 has low correlation with ECMWF over the globe, and high value with GEOS near the Korean peninsula. Lower correlations (r < 0.6) between MSU4 and SC4 (or ECMWF) occur over $30^{\circ}$N latitude belt, where subtropical jet stream passes. Temporal correlation among them over the globe is generally high (r > 0.6). Four kinds of lower stratospheric temperature data near the Korean peninsula commonly show cooling trends, of which the SC4 values (-0.82 K/decade) is the largest.

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Continuity Simulation and Trend Analysis of Water Qualities in Incoming Flows to Lake Paldang by Log Linear Models (로그선형모델을 이용한 팔당호 유입지류 수질의 연속성 시뮬레이션과 경향 분석)

  • Na, Eun-Hye;Park, Seok-Soon
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.336-343
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    • 2003
  • Two types of statistical models, simple and multivariate log linear models, were studied for continuity simulation and trend analysis of water qualities in incoming flows to Lake Paldang. Water quality is a function of one independent variable (flow) in the simple log linear model, and of three different variables (flow, time, and seasonal cycle) in multivariate model. The independent variables act as surrogate variables of water quality in both models. The model coefficients were determined by the monthly data. The water qualities included 5-day Biochemical Oxygen Demand ($BOD_5$), Total Nitrogen (TN), and Total Phosphorus (TP) measured from 1995 to 2000 in the South and the North branches of Han River and the Kyoungan Stream. The results indicated that the multivariate model provided better agreements with field measurements than the simple one in a31 attempted cases. Flow dependency, seasonality, and temporal trends of water quality were tested on the determined coefficients of the multivariate model. The test of flow dependency indicated that BOD concentrations decreased as the water flow increased. In TN and TP concentrations, however, there were no discernible flow effects. From the temporal trend analyses, the following results were obtained: 1) no trends on BOD at all three upstreams, 2) increase on TN at the South Branch and the Kyoungan Stream, 3)decrease on TN at the North Branch,4) no trends on TP at the North and the South Branches and 5) increase on TP at the Kyoungan Stream by 3 to 8% per years. The seasonality test showed that there were significant seasonal variations in all three water qualities at three incoming flows.

Geochemical Studies of the Trace Element of the Basalt in the Kilauea, Hawaii (킬라우에아 현무암의 미량원소에 대한 지구화학적 연구)

  • Park, Byeong-Jun;Jang, Yun-Deuk;Kwon, Suk-Bom;Kim, Jeong-Jin
    • Economic and Environmental Geology
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    • v.40 no.5
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    • pp.675-689
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    • 2007
  • Kilauea volcano's summit area was formed by continuous ind/or sporadic eruption activities for several hundreds years. In this study, we mainly focused on the trace elements characteristics through systematic sample rocks erupted from 1790 to September of 1982. Under the microscope it can be observed some main minerals such as olivine, clinopyroxene. and plagioclase with minor opaque minerals including Cr-spinel and ilmenite. Zr, V, Y, Ti elements show incompatible activities with MgO while Ni, Cr, Co elements show highly compatible properties. Elements like as Ba, Rb, Th, Sr, Nd are highly incompatible to show positive trends with $K_2O$. In the REE diagram LREE is more enriched than HREE suggesting typical Oceanic Island Basalt(OIB) type. It can be suggested that Sr have an effect on the fractionation of plagioclase from the kink in the $K_2O$ variation diagram. Y/Ho ratio diagram shows there was no fluids effect in the historical Kilauea volcano but Zr/Hf ratio diagram shows a significant difference between Kilauea lavas and PuuOo lavas. There are distinctive changes of trace element contents showing in particular abrupt changes of temporal variations between 1924 and 1954. Moreover, PuuOo lavas which had been erupted since 1983 follow these decreasing trends of trace element variation. Therefore, it is strongly suggested that these abrupt changes of trace elements trends result from the huge collapse geological event which formed Halemaumau crater in 1924 causing contamination effects of crustal contents into magma chamber and from the changes of parental magma composition injected into Kilauea volcano's summit magma reservoir.

Floral Pigmentation and Expression of Anthocyanin-Related Genes in Bicolored Roses 'Pinky Girl' as Affected by Temporal Heat Stress (일시적 고온 스트레스가 복색 장미 'Pinky Girl'의 화색 및 관련 유전자 발현에 미치는 영향)

  • Lee, Seul Ki;Kim, Wan Soon
    • Horticultural Science & Technology
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    • v.33 no.6
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    • pp.923-931
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    • 2015
  • This study was conducted to investigate petal pigmentation and the expression patterns of anthocyanin-related genes in bicolored roses 'Pinky Girl' treated with temporal heat stress (THS). Cyanin accumulation in petals was correlated with floral bud development and started rapidly as floral buds began to open, defined as the $4^{th}$ stage of floral bud development ($S_4$). This stage seems to be most susceptible to petal pigmentation. The total of cyanin pigmentation at blooming was significantly decreased (by 45.5%) with exposure to THS ($39/18^{\circ}C$ for three days at $S_4$) in comparison with control. Meanwhile, the expression of anthocyanin-related genes such as CHS, CHI, F3'H, DFR, ANS, 3GT, and 5GT was relatively promoted by THS. Only F3H was less expressed (by 26.7%) with THS treatment; thus, F3H could be a key gene for bicolor promotion in 'Pinky Girl' among anthocyanin-related genes. Overall, the expression pattern of the most anthocyanin-related genes did not match the trends of cyanin pigmentation in petals. These results suggest that floral pigmentation could be associated with other mechanisms related to anthocyanin biosynthesis such as post-translational effects and regulatory genes.

Characteristics of PM2.5 Emission and Distribution in a Highly Commercialized Area in Seoul, Korea (상업지역의 초미세먼지(PM2.5) 발생특성 연구)

  • Seo, Young-Ho;Ku, Myeong-Seong;Choi, Jin-Won;Kim, Kyeong-Min;Kim, Sang-Mi;Sul, Kyung-Hwa;Jo, Hyo-Jae;Kim, Su-Jin;Kim, Ki-Hyun
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.2
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    • pp.97-104
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    • 2015
  • The pollution of particulate matter (PM) is considered one of the hot socioenvironmental issues at present time. In this study, we investigated the distribution of fine particulate matter ($PM_{2.5}$) in Wangsimni commercial areas in Seoul, Korea to learn more about its environmental behavior in an urban area. Our analysis of $PM_{2.5}$ was made to distinguish the $PM_{2.5}$ pollution levels between three different types of site characteristics: (1) densely populated area, (2) thinly populated area, and (3) traffic roadside. Moreover, to assess the temporal trends in our study, the concentration levels of $PM_{2.5}$ were also compared between weekdays and weekends and between early in the afternoon and evening. The average concentration of $PM_{2.5}$ from densely and thinly populated areas were measured as $36.0{\pm}13.1$ and $32.3{\pm}11.2{\mu}g/m^3$, respectively. If the results are compared between different time bands, there were apparent differences between weekdays ($29.6{\pm}10.8{\mu}g/m^3$) and weekends ($36.9{\pm}12.1{\mu}g/m^3$). Such difference was also evident between noon ($27.8{\pm}5.8{\mu}g/m^3$) and evening ($38.3{\pm}13.7{\mu}g/m^3$). According to our research, concentration of $PM_{2.5}$ in the study area was affected more sensitively by time zone rather than the population density. The measurement data was also analyzed by drawing concentration map of $PM_{2.5}$ in the Wangsimni commercial areas based on data contouring method.

A Study on 4D GIS Technology Trends and Development Strategies (4D GIS 기술동향 및 개발전략 연구)

  • 최환석;김은형;조대수
    • Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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    • 2004.03a
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    • pp.173-187
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    • 2004
  • The horizon of using GIS technologies can be expanded to analyzing spatial changes by time in reality. Traditional GIS technologies usually use maps for a snapshot aspect of spatial information. Limitations of the present GIS technologies in terms of dealing with spatial changes require more solutions for collecting, processing and analyzing spatial data with time. Traditional GIS technologies include Temporal GIS, Real-time GIS and Virtual GIS respectively but those are not capable enough to represent spatial change in an overall perspective. By reflecting dynamic changes the current GIS technologies can be more useful and valuable than before. This study assumes that '4D GIS', a composite of temporal, realtime and virtual GIS technology, will open a new horizon for the future sophisticated GIS applications. By identifying a technology application model for 4D GIS the new concept of 4D GIS can be clarified. The model is established by combining dynamic spatial information types and applicable 4D GIS technologies, which are identified from the most current 4D application and research efforts. The technology application model for 4D GIS can be expected to contribute to efficient in planning for 4D GIS technology development in the future.he future.

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A Review of Change Detection Techniques using Multi-temporal Synthetic Aperture Radar Images (다중시기 위성 레이더 영상을 활용한 변화탐지 기술 리뷰)

  • Baek, Won-Kyung;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.35 no.5_1
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    • pp.737-750
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    • 2019
  • Information of target changes in inaccessible areas is very important in terms of national security. Fast and accurate change detection of targets is very important to respond quickly. Spaceborne synthetic aperture radar can acquire images with high accuracy regardless of weather conditions and solar altitude. With the recent increase in the number of SAR satellites, it is possible to acquire images with less than one day temporal resolution for the same area. This advantage greatly increases the availability of change detection for inaccessible areas. Commonly available information in satellite SAR is amplitude and phase information, and change detection techniques have been developed based on each technology. Those are amplitude Change Detection (ACD), Coherence Change Detection (CCD). Each algorithm differs in the preprocessing process for accurate automatic classification technique according to the difference of information characteristics and the final detection result of each algorithm. Therefore, by analyzing the academic research trends for ACD and CCD, each technologies can be complemented. The goal of this paper is identifying current issues of SAR change detection techniques by collecting research papers. This study would help to find the prerequisites for SAR change detection and use it to conduct periodic detection research on inaccessible areas.

Spatial and temporal trends in food security during the COVID-19 pandemic in Asia Pacific countries: India, Indonesia, Myanmar, and Vietnam

  • Yunhee Kang;Indira Prihartono;Sanghyo Kim;Subin Kim;Soomin Lee;Randall Spadoni;John McCormack;Erica Wetzler
    • Nutrition Research and Practice
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    • v.18 no.1
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    • pp.149-164
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    • 2024
  • BACKGROUND/OBJECTIVES: The economic recession caused by the coronavirus disease 2019 pandemic disproportionately affected poor and vulnerable populations globally. Better uunderstanding of vulnerability to shocks in food supply and demand in the Asia Pacific region is needed. SUBJECTS/METHODS: Using secondary data from rapid assessment surveys during the pandemic response (n = 10,420 in mid-2020; n = 6,004 in mid-2021) in India, Indonesia, Myanmar, and Vietnam, this study examined the risk factors for reported income reduction or job loss in mid-2021 and the temporal trend in food security status (household food availability, and market availability and affordability of essential items) from mid-2020 to mid-2021. RESULTS: The proportion of job loss/reduced household income was highest in India (60.4%) and lowest in Indonesia (39.0%). Urban residence (odds ratio [OR] range, 2.20-4.11; countries with significant results only), female respondents (OR range, 1.40-1.69), engagement in daily waged labor (OR range, 1.54-1.68), and running a small trade/business (OR range, 1.66-2.71) were significantly associated with income reduction or job loss in three out of 4 countries (all P < 0.05). Food stock availability increased significantly in 2021 compared to 2020 in all four countries (OR range, 1.91-4.45) (all P < 0.05). Availability of all essential items at markets increased in India (OR range, 1.45-3.99) but decreased for basic foods, hygiene items, and medicine in Vietnam (OR range, 0.81-0.86) in 2021 compared to 2020 (all P < 0.05). In 2021, the affordability of all essential items significantly improved in India (OR range, 1.18-3.49) while the affordability of rent, health care, and loans deteriorated in Indonesia (OR range, 0.23-0.71) when compared to 2020 (all P < 0.05). CONCLUSIONS: Long-term social protection programs need to be carefully designed and implemented to address food insecurity among vulnerable groups, considering each country's market conditions, consumer food purchasing behaviors, and financial support capacity.

Spatiotemporal Trends of Malaria in Relation to Economic Development and Cross-Border Movement along the China-Myanmar Border in Yunnan Province

  • Zhao, Xiaotao;Thanapongtharm, Weerapong;Lawawirojwong, Siam;Wei, Chun;Tang, Yerong;Zhou, Yaowu;Sun, Xiaodong;Sattabongkot, Jestumon;Kaewkungwal, Jaranit
    • Parasites, Hosts and Diseases
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    • v.58 no.3
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    • pp.267-278
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    • 2020
  • The heterogeneity and complexity of malaria involves political and natural environments, socioeconomic development, cross-border movement, and vector biology; factors that cannot be changed in a short time. This study aimed to assess the impact of economic growth and cross-border movement, toward elimination of malaria in Yunnan Province during its pre-elimination phase. Malaria data during 2011-2016 were extracted from 18 counties of Yunnan and from 7 villages, 11 displaced person camps of the Kachin Special Region II of Myanmar. Data of per-capita gross domestic product (GDP) were obtained from Yunnan Bureau of Statistics. Data were analyzed and mapped to determine spatiotemporal heterogeneity at county and village levels. There were a total 2,117 malaria cases with 85.2% imported cases; most imported cases came from Myanmar (78.5%). Along the demarcation line, malaria incidence rates in villages/camps in Myanmar were significantly higher than those of the neighboring villages in China. The spatial and temporal trends suggested that increasing per-capita GDP may have an indirect effect on the reduction of malaria cases when observed at macro level; however, malaria persists owing to complex, multi-faceted factors including poverty at individual level and cross-border movement of the workforce. In moving toward malaria elimination, despite economic growth, cooperative efforts with neighboring countries are critical to interrupt local transmission and prevent reintroduction of malaria via imported cases. Cross-border workers should be educated in preventive measures through effective behavior change communication, and investment is needed in active surveillance systems and novel diagnostic and treatment services during the elimination phase.

Changing Susceptibility of Staphylococcus aureus in Children with Skin and Soft Tissue Infections: a Single Center Experience from 2010 to 2018 (소아 피부 및 연조직 감염 환자에서의 황색포도알균의 항생제 감수성의 변화: 2010년부터 2018년까지 단일기관에서의 경험)

  • Cho, Yong-Sun;Lee, Shin-Hye;Lee, Taek-Jin
    • Pediatric Infection and Vaccine
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    • v.26 no.3
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    • pp.140-147
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    • 2019
  • Purpose: Staphylococcus aureus is a major cause of skin and soft tissue infections (SSTIs). This study aimed to determine the temporal trends in antibiotic susceptibility of S. aureus in SSTI patients aged <19 years. Methods: This retrospective observational study was conducted in pediatric patients with SSTI caused by community-associated S. aureus. Microbiologic and demographic data were collected, and the trends of antibiotic susceptibility results were evaluated. Results: From January 2010 to December 2018, a total of 807 S. aureus isolates were included. An overall increase in susceptibility of isolates to oxacillin was noted (P<0.001), with 75.0% of isolates being oxacillin-susceptible in 2018. S. aureus remained highly susceptible to trimethoprim/sulfamethoxazole and tetracycline, with 97.6% and 95.2% isolate susceptibility in 2018, respectively. Isolates from younger children aged 1 to 5 years had a significantly lower rate of susceptibility to oxacillin than older children aged 6 to 18 years (53.4% vs. 75.0%, P<0.001). Conclusions: The proportion of methicillin-resistant S. aureus isolates appears to decrease in pediatric patients with community-associated SSTI caused by S. aureus. Clinicians should be aware of regional susceptibility patterns when choosing empirical regimens.