• Title/Summary/Keyword: Temporal changes

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Soil Carbon Dioxide Flux and Organic Carbon in Grassland after Manure and Ammonium Nitrate Application

  • Lee, Do-Kyoung;Doolittle, James J.
    • Korean Journal of Environmental Agriculture
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    • v.24 no.3
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    • pp.238-244
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    • 2005
  • Fertilization effects on changes in soil $CO_2$ flux and organic C in switchgrass (Panicum virgatum L.) land managed for biomass production were investigated. The mean daily soil $CO_2$ flux in the manure treatment was 5.63 g $CO_2-C\;m^{-2}\;d^{-1}$, and this was significantly higher than the mean value of 3.36 g $CO_2-C\;m^{-2}\;d^{-1}$ in the control. The mean daily $CO_2$ fluxes in N and P fertilizer treatments plots were not different when compared to the value in the control plots. Potentially mineralizable C (PMC), soil microbial biomass C (SMBC), and particulate organic C (POC) were highest at the 0 to 10 cm depth of the manure treatment. Potentially mineralizable C had the strongest correlation with SMBC (r = 0.91) and POC (r = 0.84). There was also a strong correlation between SMBC and POC (r = 0.90). Our results indicated that for the N and P levels studied, fertilization had no impact on temporal changes in soil organic C, but manure application had a significant impact on temporal changes in soil $CO_2$ evolution and active C constituents such as PMC, SMBC, and POC.

A Study on Design of Ontologies-Driven Design of Context-based Historical-Cultural of U-Service in U-City (U-City에 있어서 U-Service의 콘텍스트 기반 역사문화 온톨로지 설계 관한 연구)

  • Kwon, Chang-Hee
    • Journal of Digital Convergence
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    • v.9 no.6
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    • pp.379-387
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    • 2011
  • Historical-cultural contents are digitized documents of records or evidences about changes of human society. The changes or evolvements are results of the interaction between society and environment. So the different feafures are appears by spatio-temporal observing locations Historical-cultural contents need to be designed so that the preservation and exchange of information, adaptation to changes of the future are easy. So historical-cultural contents have structured to support the intelligent services based on context. This study propose context-based ontology-design method based on events, and we implemented web services of Bible contents by proposed method.

A study on the Quality Characteristics of Rice Bread Containing Trehalose (트레할로스를 첨가한 쌀식빵의 품질특성)

  • Bae, Dae Seok;Lee, Jin Shik
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.2
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    • pp.568-577
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    • 2018
  • This study was conducted to evaluate the quality characteristics. Trehalose was used to manufacture rice bread in two ways: one was to substitute trehalose for sugar by (0, 25, 50, and 75%) trehalose in each sample and the other was to analyze the temporal changes in rice bread on Day 0, on Day 2, and on Day 4. The results concerning the characteristics of specific volumes, water content, water activity, variation in weight and height, physical property test, and sensory test and measurements of the temporal changes are as follows: First, as for variation in specific volumes, rice bread containing trehalose had the content and temporal changes decrease significantly (p<0.001). Second, as for texture, a higher trehalose content led to a slightly lower level of hardness. As for the temporal changes, addition of trehalose is generally effective in decreasing hardness of rice bread. the sample containing trehalose showed an almost similar value. The control group not containing trehalose showed the significantly lowest level of cohesiveness, springiness, Chewiness. Finally, the sensory evaluations revealed that the taste, Flavor, and Sweetness was at a significantly higher level in the group with trehalose substituted for sugar than in the control group. An increase in the trehalose content led to an increase in overall eating quality.

A Study on Detection of Deforested Land Using Aerial Photographs (항공사진을 이용한 훼손 산지 탐지 연구)

  • Ham, Bo Young;Lee, Chun Yong;Byun, Hye Kyung;Min, Byoung Keol
    • Journal of Korean Society for Geospatial Information Science
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    • v.21 no.3
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    • pp.11-17
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    • 2013
  • With high social demands for the diverse utilizations of forest lands, the illegal forest land use changes have increased. We studied change detection technique to detect changes in forest land use using an object-oriented segmentation of RED bands differencing in multi-temporal aerial photographs. The new object-oriented segmentation method consists of the 5 steps, "Image Composite - Segmentation - Reshaping - Noise Remover - Change Detection". The method enabled extraction of deforested objects by selecting a suitable threshold to determine whether the objects was divided or merged, based on the relations between the objects, spectral characteristics and contextual information from multi-temporal aerial photographs. The results found that the object-oriented segmentation method detected 12% of changes in forest land use, with 96% of the average detection accuracy compared by visual interpretation. Therefore this research showed that the spatial data by the object-oriented segmentation method can be complementary to the one by a visual interpretation method, and proved the possibility of automatically detecting and extracting changes in forest land use from multi-temporal aerial photographs.

Influence of Greenhouse Gases on Radiative Forcing at Urban Center and Background Sites on Jeju Island Using the Atmospheric Radiative Transfer Model (대기복사전달모델을 이용한 제주지역 도심 및 배경지점에서의 온실가스에 따른 복사강제력 영향 연구)

  • Lee, Soo-Jeong;Song, Sang-Keun;Han, Seung-Beom
    • Atmosphere
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    • v.27 no.4
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    • pp.423-433
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    • 2017
  • The spatial and temporal variations in radiative forcing (RF) and mean temperature changes of greenhouse gases (GHGs), such as $CO_2$, $CH_4$, and $N_2O$, were analyzed at urban center (Yeon-dong) and background sites (Gosan) on Jeju Island during 2010~2015, based on a modeling approach (i.e., radiative transfer model). Overall, the RFs and mean temperature changes of $CO_2$ at Yeon-dong during most years (except for 2014) were estimated to be higher than those at Gosan. This might be possibly because of its higher concentrations at Yeon-dong due to relatively large energy consumption and small photosynthesis and also the difference in radiation flux due to the different input condition (e.g., local time and geographic coordinates of solar zenith angle) in the model. The annual mean RFs and temperature changes of $CO_2$ were highest in 2015 ($2.41Wm^{-2}$ and 1.76 K) at Yeon-dong and in 2013 ($2.22Wm^{-2}$ and 1.62 K) at Gosan (except for 2010 and 2011). The maximum monthly/seasonal mean RFs and temperature changes of $CO_2$ occurred in spring (Mar. and/or Apr.) or winter (Jan. and/or Feb.) at the two sites during the study period, whereas the minimum RFs and temperature changes in summer (Jun.-Aug.). In the case of $CH_4$ and $N_2O$, their impacts on the RF and mean temperature changes were very small (an order of magnitude lower) compared to $CO_2$. The spatio-temporal differences in these RF values of GHGs might primarily depend on the atmospheric profile (e.g., ozone profile), surface albedo, local time (or solar zenith angle), as well as their mass concentrations.

A Study on Temporality of 'Phenomenology of music' in Rem Koolhaas's space (렘 콜하스 공간의 음악현상학적 시간성에 대한 연구)

  • Kang, So-Yeon;Yoon, Sang-Young;Yoon, Jae-Eun
    • Korean Institute of Interior Design Journal
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    • v.22 no.1
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    • pp.115-123
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    • 2013
  • Today, the views on Temporality of space have been changed not only to be based on the concept of time, but also to identify the space with a body adapted to the new circumstances. The study suggests that the actions of performers in space have been important by changes of views and are connected to the music phenomenology mixed with music whose tempo is the phenomenology related with of human consciousness itself, and derives the temporal property by putting them into Rem Koolhaas space with the fluid quality. According to Clifton's Phenomenology of Music, an understanding of music is made in both human body and consciousness as two ways to listen to sounds and enjoy music. Though a correlation between the characteristics of Clifton's Phenomenology of Music and one of resulted from uncertainty and immateriality of modern space Temporality, we could work out four kinds of characters which are the continuity of the fluidity from temporal programs, contrasting changes or synchronicity, the multidimensionality from synesthesia of line and face, ventilation by quality of the material and immaterial circumstances of sound effects, the implication in events resulted from cognition for information and unexpected actions, and the autonomy of the route of a variety of experiences including intimate connection of inter-related events and temporary and diverse external conditions. Hereby Temporality of musical phenomenology in Rem Koolhaas's space can be experienced by systems base oh the importance of host's motion, changes of programs according to the motion as well as uncertainty and immaterial changes. Due to the changes user's emotion and motion is undergone as Temporality that changes automatically.

Errors in Estimated Temporal Tracer Trends Due to Changes in the Historical Observation Network: A Case Study of Oxygen Trends in the Southern Ocean

  • Min, Dong-Ha;Keller, Klaus
    • Ocean and Polar Research
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    • v.27 no.2
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    • pp.189-195
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    • 2005
  • Several models predict large and potentially abrupt ocean circulation changes due to anthropogenic greenhouse-gas emissions. These circulation changes drive-in the models-considerable oceanic oxygen trend. A sound estimate of the observed oxygen trends can hence be a powerful tool to constrain predictions of future changes in oceanic deepwater formation, heat and carbon dioxide uptake. Estimating decadal scale oxygen trends is, however, a nontrivial task and previous studies have come to contradicting conclusions. One key potential problem is that changes in the historical observation network might introduce considerable errors. Here we estimate the likely magnitude of these errors for a subset of the available observations in the Southern Ocean. We test three common data analysis methods south of Australia and focus on the decadal-scale trends between the 1970's and the 1990's. Specifically, we estimate errors due to sparsely sampled observations using a known signal (the time invariant, temporally averaged, World Ocean Atlas 2001) as a negative control. The crossover analysis and the objective analysis methods are for less prone to spatial sampling location biases than the area averaging method. Subject to numerous caveats, we find that errors due to sparse sampling for the area averaging method are on the order of several micro-moles $kg^{-1}$. for the crossover and the objective analysis method, these errors are much smaller. For the analyzed example, the biases due to changes in the spatial design of the historical observation network are relatively small compared to the tends predicted by many model simulations. This raises the possibility to use historic oxygen trends to constrain model simulations, even in sparsely sampled ocean basins.

Mapping Paddy Rice Varieties Using Multi-temporal RADARSAT SAR Images

  • Jang, Min-Won;Kim, Yi-Hyun;Park, No-Wook;Hong, Suk-Young
    • Korean Journal of Remote Sensing
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    • v.28 no.6
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    • pp.653-660
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    • 2012
  • This study classified paddy fields according to rice varieties and monitored temporal changes in rice growth using SAR backscatter coefficients (${\sigma}^{\circ}$). A growing period time-series of backscatter coefficients was set up for nine fine-beam mode RADARSAT-1 SAR images from April to October 2005. The images were compared with field-measured rice growth parameters such as leaf area index (LAI), plant height, fresh and dry biomass, and water content in grain and plants for 45 parcels in Dangjin-gun, Chungnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) ranged from -18.17 dB to -6.06 dB and were lower than those for medium-late maturing rice varieties during most of the growing season. Both crops showed the highest backscatter coefficient values at the heading stage (late July) for early-maturing rice, and the difference was greatest before harvest for early-maturing rice. The temporal difference in backscatter coefficients between rice varieties may play a key role in identifying early-maturing rice fields. On the other hand, comparisons with field-measured parameters of rice growth showed that backscatter coefficients decreased or remained on a plateau after the heading stage, even though the growth of the rice canopy had advanced.

A Potential Risk of Radiation-Induced Cavernous Malformations Following Adjuvant Gamma Knife Radiosurgery for Mesial Temporal Lobe Epilepsy

  • Junhyung Kim;Joonho Byun;Do Heui Lee;Seok Ho Hong
    • Journal of Korean Neurosurgical Society
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    • v.67 no.4
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    • pp.458-466
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    • 2024
  • Objective : Several clinical studies have explored the feasibility and efficacy of radiosurgical treatment for mesial temporal lobe epilepsy, but the long-term safety of this treatment has not been fully characterized. This study aims to report and describe radiation-induced cavernous malformation as a delayed complication of radiosurgery in epilepsy patients. Methods : The series includes 20 patients with mesial temporal lobe epilepsy who underwent Gamma Knife radiosurgery (GKRS). The majority received a prescribed isodose of 24 Gy as an adjuvant treatment after anterior temporal lobectomy. Results : In this series, we identified radiation-induced cavernous malformation in three patients, resulting in a cumulative incidence of 18.4% (95% confidence interval, 6.3% to 47.0%) at an 8-year follow-up. These late sequelae of vascular malformation occurred between 6.9 and 7.6 years after GKRS, manifesting later than other delayed radiation-induced changes, such as radiation necrosis. Neurological symptoms attributed to intracranial hypertension were present in those three cases involving cavernous malformation. Of these, two cases, which initially exhibited an insufficient response to radiosurgery, ultimately demonstrated seizure remission following the successful microsurgical resection of the cavernous malformation. Conclusion : All things considered, the development of radiation-induced cavernous malformation is not uncommon in this population and should be acknowledged as a potential long-term complication. Microsurgical resection of cavernous malformation can be preferentially considered in cases where the initial seizure outcome after GKRS is unsatisfactory.

Changes of the Cerebral Blood Flow During Event Related Petential Test to Auditory Stimuli : A Transcranial Doppler Study (인지유발전위중의 뇌혈류변화 : 초음파뇌혈류검사)

  • Kim, Jong-Yeol
    • Annals of Clinical Neurophysiology
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    • v.1 no.1
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    • pp.26-30
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    • 1999
  • Background : The origin of P300 was still on debate nbut thought to be in the frontal, temporal or parietal lobe. As the transcranial doppler ultrasonography(TCD) gives us and opportunity to observe hemodynamic chaged dynamically and the middle cerebral artery feeds these ares of the hemisphere, we observed the change of mean flow velocity of MCA during the event related potential test(ERP) to determine the role of these structures in P300 generation. Method : Twenty normal subjects(male : 13, age : 24-29 years) performed ERP. An auditory oddball pardigm was used to elicit the ERPs. TCD examination was performed with 2-MHz probe monitoring the left MCA(Transscan, EME). After signal identification and adjustments to maximize the Doppler signal strength, the probe was mechanically locked during the monitoring. The changes of blood flow velocity of the left middle cerebral artery(MCA) induced by cognitive demands were monitored. The measurement of the meal flow velocities(MFV) of MCA were made while the subjects were prior to, during, and after ERP. We recorded the MFVs during ERP. Statistical analysis was performed using t-tests with SPSS-PC for windows release 6.0. Results : All subjects showed a relative increase in MFV of MCA during the task. The mean rise was about 3.2-4.2%(p <0.05). Although TCD does not measure absolute values of regional cerebral blood flow(rCBF) or absolute rCBF changes, changes of flow velocity can reflect relative rCBF changes. Conclusions : The generation site of P300 still remains unclear but the neocortical, thalamic and limbic region and temporal-parietal cortex have been proposed. The MCA supplies these anatomical structures. The Changes of flow veolocity of MCA during the ERP test suggest that the some part of the brain fed y the MCA activate of the temporal lobe or parietal lobes, we can deduce that some parts of brain fed by the MCA participate in the generation of P300.

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