• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.161-161
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• 2023

Bias correction of values is a necessary step in downscaling coarse and systematically biased global climate models for use in local climate change impact studies. In addition to univariate bias correction methods, many multivariate methods which correct multiple variables jointly - each with their own mathematical designs - have been developed recently. While some literature have focused on the inter-comparison of these multivariate bias correction methods, none have focused extensively on the effect of diverse configurations (i.e., different combinations of input variables to be corrected) of climate variables, particularly high-dimensional ones, on the ability of the different methods to remove biases in uni- and multivariate statistics. This study evaluates the impact of three configurations (inter-variable, inter-spatial, and full dimensional dependence configurations) on four state-of-the-art multivariate bias correction methods in a national-scale domain over South Korea using a gridded approach. An inter-comparison framework evaluating the performance of the different combinations of configurations and bias correction methods in adjusting various climate variable statistics was created. Precipitation, maximum, and minimum temperatures were corrected across 306 high-resolution (0.2°) grid cells and were evaluated. Results show improvements in most methods in correcting various statistics when implementing high-dimensional configurations. However, some instabilities were observed, likely tied to the mathematical designs of the methods, informing that some multivariate bias correction methods are incompatible with high-dimensional configurations highlighting the potential for further improvements in the field, as well as the importance of proper selection of the correction method specific to the needs of the user.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.281-285
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• 1996

On farm demonstration of urea treatment (5 kg urea dissolved in 60 litre water/100kg) of straw was performed at 6 different sites and treated straw was stored by three different methods i.e., plastic covered, mud plastered and existing farmers technique (mud plastered on the top and open from sides) to determine the best storage method in field. Untreated and treated samples were taken after 5 week storage period and subjected to crude protein, crude fibre and cell wall constituents analysis. In situ dry matter digestibility of straw was measured by nylon bag technique in buffalo bulls. Crude protein content increased by 100 to 153 percent in treated straw stored by different methods. Maximum increase in crude protein of treated straw was noticed in mud plastered method. Urea treatment of straw resulted in significant decrease in crude fibre contents in all the storage methods. Treatment of straw enhanced the in situ digestibility by 25-49 percent and maximum digestibility (53%) was found in mud plastered storage method. It was concluded that the mud plastered storage method for urea treated straw was found to be the best at farm level.

• Korean Journal of Ecology and Environment
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• v.41 no.spc
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• pp.1-10
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• 2008

We patterned water quality of agricultural reservoirs according to the differences of six physico-chemical environmental factors (TN, TP, DO, BOD, COD, and SS) using four different ordination methods: Principal Components Analysis (PCA), Detrended Correspondence Analysis (DCA), Nonmetric Multidimensional Scaling (NMS), and Isometric Feature Mapping (Isomap). The data set was obtained from the water quality monitoring networks operated by the Ministry of Agriculture and Forestry and the Ministry of Environments. Chlorophyll-${\alpha}$ displayed the highest correlation with COD, followed by TP, BOD, SS, and TN (p<0.01), while negatively correlated with altitude and bank height of the reservoirs (p<0.01). Although four different ordination methods similarly patterned the reservoirs according to the gradient of nutrient concentration, PCA and NMS appeared to be the most efficient methods to pattern water quality of reservoirs based on the explanation power. Considering variable scores in the ordination map, the concentration of nutrients was positively correlated with Chl-${\alpha}$, while negatively correlated with altitude and bank height. These ordination methods may help to pattern agricultural reservoirs according to their water quality characteristics.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.201-207
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• 2007

Researchers have used a variety of methods to measure patterns of animal movement, including the use of spatial data (mapping the position of a moving animal at specified intervals) and direct estimation of travel path length by pacing under a moving animal or group. I collected movement data from five groups of siamangs (Symphalangus syndactylus) using two different methods concurrently to estimate the effects of the method of data collection on estimates of daily path length (DPL). Estimates of DPL produced from spatial data collected at 15-minute intervals were 12% lower than estimates of DPL produced by pacing under the traveling animal. The actual magnitude of the difference was correlated with the travel distance, but there was no correlation between the proportional difference and the travel distance. While the collection of spatial data is generally preferable, as spatial data permit additional analyses of patterns of movements in two or three dimensions, the relatively small difference between the DPL's produced using different methods suggests that pacing is an acceptable substitute where the collection of spatial data is impractical. I also subsampled the spatial data at increasing time intervals to assess the effect of sampling interval on the calculation of daily path lengths. Longer sampling intervals produced significantly shorter estimates of travel paths than shorter sampling intervals. These results suggest that spatial data should be collected at short time intervals wherever possible, and that sampling intervals should not exceed 30 minutes. Researchers should be cautious when comparing data generated using different methods.

• Annals of Clinical Neurophysiology
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• v.12 no.1
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• pp.16-20
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• 2010

Background: The medial plantar nerve (MPN) is a distal branch of the posterior tibial nerve, and various methods of nerve conduction study for MPN have been introduced so far. Hemmi et al described a new method (Hemmi's method) for recording medial plantar sensory nerve action potentials (SNAPs), which is considered as a simple and reliable method for measuring medial plantar SNAPs. This study was aimed to establish the normal values for the MPN conduction study among Koreans and to compare the sensitivities of three different methods for MPN conduction study (Hemmi, Oh, and Saeed's method) in detecting evidence of peripheral neuropathy among diabetic patients. Methods: In 27 healthy subjects, MPN conduction study using Hemmi's method was performed and normal values were calculated. In 54 diabetic patients who showed normal routine nerve conduction studies, three different methods for MPN conduction study were performed and diagnostic sensitivity of each method were compared. Results: In normal subjects, the mean medial plantar SNAP amplitude and conduction velocities measured by Hemmi's method were $4.3{\pm}1.0$ uV and $38.3{\pm}6.8$ m/s respectively. Among 54 patients with diabetes who showed normal routine nerve conduction studies, medial plantar SNAP was not obtainable in 28, 31, and 6 patients by Hemmi, Oh and Saeed's method respectively. Conclusions: In terms of the diagnostic sensitivity for detecting diabetic neuropathy, there had been no significant statistical difference between three different methods. Our study suggested that MPN conduction study using Hemmi's method is simple and useful screening test for early diabetic neuropathy, and is comparable with Oh's method.

• Journal of Environmental Impact Assessment
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• v.21 no.4
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• pp.593-607
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• 2012

The Ministry of Environment have started the 'National Ecosystem Survey' since 1986. It has been carried out nationwide every ten years as the largest survey project in Korea. The second one and the third one produced the GIS-based inventory of species. Three survey methods were different from each other. There were few studies for species distribution using national survey data in Korea. The purposes of this study are to test species distribution models for finding the most suitable modeling methods for the National Ecosystem Survey data and to investigate the modeling results according to survey methods and taxonominal group. Occurrence data of nine species were extracted from the National Ecosystem Survey by taxonomical group (plant, mammal, and bird). Plants are Korean winter hazel (Corylopsis coreana), Iris odaesanensis (Iris odaesanensis), and Berchemia (Berchemia berchemiaefolia). Mammals are Korean Goral (Nemorhaedus goral), Marten (Martes flavigula koreana), and Leopard cat (Felis bengalensis). Birds are Black Woodpecker (Dryocopus martius), Eagle Owl (Bubo Bubo), and Common Buzzard (Buteo buteo). Environmental variables consisted of climate, topography, soil and vegetation structure. Two modeling methods (GAM, Maxent) were tested across nine species, and predictive species maps of target species were produced. The results of this study were as follows. Firstly, Maxent showed similar 5 cross-validated AUC with GAM. Maxent is more useful model to develop than GAM because National Ecosystem Survey data has presence-only data. Therefore, Maxent is more useful species distribution model for National Ecosystem Survey data. Secondly, the modeling results between the second and third survey methods showed sometimes different because of each different surveying methods. Therefore, we need to combine two data for producing a reasonable result. Lastly, modeling result showed different predicted distribution pattern by taxonominal group. These results should be considered if we want to develop a species distribution model using the National Ecosystem Survey and apply it to a nationwide biodiversity research.

• Restorative Dentistry and Endodontics
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• v.41 no.4
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• pp.283-295
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• 2016

Objectives: In this study, we characterized human dental pulp cells (HDPCs) obtained by different culture methods to establish the most suitable methodology for dental tissue engineering and regenerative endodontic applications. Materials and Methods: HDPCs were isolated by the outgrowth method (HDPCs-OG), the enzymatic digestion method (collagenase/dispase/trypsin, HDPCs-ED), or the combination of both methods (HDPCs-Combined). The expression of mesenchymal stem cell markers (CD105, CD90, and CD73) was investigated. In vitro differentiation capacities of HDPCs into adipogenic, osteogenic, and chondrogenic lineages were compared. Differentiation markers were analyzed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) and western blotting. Results: Our data indicated that whole HDPCs-ED, HPDCs-OG, and HDPCs-Combined could be differentiated into adipogenic, chrondrogenic, and osteogenic cell types. However, we found that the methods for isolating and culturing HDPCs influence the differentiation capacities of cells. HDPCs-OG and HDPCs-ED were preferably differentiated into adipogenic and osteogenic cells, respectively. Differentiation markers shown by RT-PCR and western blotting analysis were mostly upregulated in the treated groups compared with the control groups. Conclusions: Our findings confirmed that cell populations formed by two different culture methods and the combined culture method exhibited different properties. The results of this study could provide an insight into regenerative endodontic treatment using HDPCs.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.3
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• pp.1071-1090
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• 2016

Most of scheduling methods in the Grid only consider one special attribute of the resource or one aspect of QoS (Quality of Service) of the job. In this paper, we focus on the problem that how to consider two aspects simultaneously. Based on the requirements of the jobs and the attributes of the resources, jobs are categorized into three kinds: CPU-overload, memory-overload, and bandwidth-overload jobs. One job may belong to different kinds according to different attributes. We schedule the jobs in different categories in different orders, and then propose a scheduling method-MTS (multiple attributes scheduling method) to schedule Grid resources. Based on the comparisons between our method, Min-min, ASJS (Adaptive Scoring Job Scheduling), and MRS (Multi-dimensional Scheduling) show: (1) MTS reduces the execution time more than 15% to other methods, (2) MTS improves the number of the finished jobs before the deadlines of the jobs, and (3) MTS enhances the file size of transmitted files (input files and output files) and improves the number of the instructions of the finished jobs.

• Plant Resources
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• v.6 no.1
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• pp.53-56
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• 2003

To develop optimal storage method of root of Anemarrhena Rhizome, which has been grown as major cultural herbal medicine material, root of Anemarrhena Rhizome was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The rot ratio of root during the storage period was not significantly different among packing materials but was significantly different among sealing conditions. Conclusively vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Anemarrhena Rhizome.

• Plant Resources
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• v.5 no.2
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• pp.114-117
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• 2002

To develop optimal storage method of root of Peucedani Radix, which has been grown as major cultural herbal medicine material, root of Peucedani Radix was stored for 10 months with different packing materials and sealing methods. The loss in dry weight as influenced by packing materials and sealing methods was the lowest at vacuum packing and followed by complete sealing methods with transparent polyethylene film. The ratio of root rot during the storage period was not significantly different between packing materials but was significantly different between sealing conditions. Conclusively vacuum packing and complete sealing with polyethylene film appears to be optimal for storage of Peucedani Radix.