• Journal of Ginseng Research
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• v.40 no.2
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• pp.127-134
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• 2016

Background: Rhizospheric fungi play an essential role in the plantesoil ecosystem, affecting plant growth and health. In this study, we evaluated the fungal diversity in the rhizosphere soil of 2-yr-old healthy Panax notoginseng cultivated in Wenshan, China. Methods: Culture-independent Illumina MiSeq and culture-dependent techniques, combining molecular and morphological characteristics, were used to analyze the rhizospheric fungal diversity. A diffusion test was used to challenge the phytopathogens of P. notoginseng. Results: A total of 16,130 paired-end reads of the nuclear ribosomal internal transcribed spacer 2 were generated and clustered into 860 operational taxonomic units at 97% sequence similarity. All the operational taxonomic units were assigned to five phyla and 79 genera. Zygomycota (46.2%) and Ascomycota (37.8%) were the dominant taxa; Mortierella and unclassified Mortierellales accounted for a large proportion (44.9%) at genus level. The relative abundance of Fusarium and Phoma sequenceswas high, accounting for 12.9% and 5.5%, respectively. In total,113 fungal isolates were isolated from rhizosphere soil. They were assigned to five classes, eight orders (except for an Incertae sedis), 26 genera, and 43 species based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer. Fusarium was the most isolated genus with six species (24 isolates, 21.2%). The abundance of Phoma was also relatively high (8.0%). Thirteen isolates displayed antimicrobial activity against at least one test fungus. Conclusion: Our results suggest that diverse fungi including potential pathogenic ones exist in the rhizosphere soil of 2-yr-old P. notoginseng and that antagonistic isolates may be useful for biological control of pathogens.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.59-59
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• 2017

Rice (Oryza sativa L.) is the most important crop and its yield must be improved to feed the increasing global population. Recently developed high-yielding varieties with extra-large sink capacity often have a problem in unstable grain-filling. Therefore, understanding limiting factors for improving grain-filling and controlling them are essential for further improvement of rice grain yield. However, since grain-filling rate was determined by complex sink-source balance, the ability of grain-filling was very difficult to evaluate. Source ability for 'grain' was not only determined by the ability of carbon assimilation in leaves, but also that of carbon translocation from leaves to panicles. Sink strength was determined by the complex carbon metabolism from sucrose degradation to starch synthesis. Hence, to evaluate the grain-filling ability and determine its regulatory steps, the whole picture of carbon flow from photosynthesis at leaves to starch synthesis at grains must be revealed in a metabolite level. In this study, the yield and grain growth rate of three high-yielding varieties, which show high sink capacity commonly, were compared. Momiroman showed lower grain filling rate and slower grain growth rate than the other varieties, Hokuriku 193 and Tequing. To clarify the limiting point in the carbon flow of Momiroman, $CO_2$ labeled by stable isotope ($^{13}C$) was fed to three varieties during ripening period. The ratio of $^{13}C$ left in the stem was higher in Momiroman 24 hours after feeding, suggesting inefficient carbon translocation of Momiroman. More interestingly, $^{13}C$ translocation from soluble fraction to insoluble one in the grain seemed to be slower in Momiroman. To get the further insight in a metabolite level, we are now trying the $^{13}C$ labeling metabolome analysis in the developing grains.

• Journal of Korea Spatial Information System Society
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• v.8 no.2 s.17
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• pp.91-107
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• 2006

To handling the extreme situation that must manage positional information of a very large volume, at least millions of moving objects. A cluster-based sealable distributed computing system architecture, called the GALIS which consists of multiple data processors, each dedicated to keeping records relevant to a different geographical zone and a different time zone, was proposed. In this paper, we proposed a valid time management and time-zone shifting scheme, which are essential in realizing the long-term location data subsystem of GALIS, but missed in our previous prototype development. We explain how to manage valid time of moving objects to avoid ambiguity of location information. We also describe time-zone shifting algorithm with three variations, such as Real Time-Time Zone Shifting, Batch-Time Zone Shifting, Table Partitioned Batch-Time Zone Shifting, Through experiments related with query processing time and CPU utilization, we show the efficiency of the proposed time-zone shifting schemes.

• Tunnel and Underground Space
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• v.23 no.4
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• pp.308-318
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• 2013

Thermal stratification in heat stores is essential to improve the efficiency of energy storage systems and deliver more useful energy on demand. It is generally well known that the degree of thermal stratification in heat stores varies depending on the aspect ratio (the height-to-width ratio) and size of the stores. The present study aims to investigate the effect of the aspect ratio and storage volume of rock caverns for storing hot water on thermal stratification in the caverns and heat loss to the surroundings. Heat transfer simulations using a computational fluid dynamics code, FLUENT were performed at different aspect ratios and storage volumes of rock caverns. The variation of thermal stratification with respect to time was examined using an index to quantify the degree of stratification, and the heat loss to the surroundings was evaluated. The results of the numerical simulations demonstrated that the thermal stratification in rock caverns was improved by increasing the aspect ratio, but this effect was not remarkable beyond an aspect ratio of 3-4. When the storage volume of rock caverns was large, a higher thermal stratification was maintained for a relatively longer time compared to caverns with a small storage volume, but the difference in thermal stratification between the two cases tended to decrease as the aspect ratio became larger. In addition, the numerical results showed that the heat loss to the surrounding rock tended to increase with an increase in aspect ratio because the surface area of rock caverns increased as the aspect ratio became larger. The total heat loss from multiple small caverns with a reduced storage volume per cavern was larger compared to a single cavern with the same total storage volume as that of the multiple caverns.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.6
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• pp.447-458
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• 2003

A high speed multiplier is essential basic building block for digital signal processors today. Typically iterative algorithms in Signal processing applications are realized which need a large number of multiply, add and accumulate operations. This paper describes a macro block of a parallel structured multiplier which has adopted a 32$\times$32-b regularly structured tree (RST). To improve the speed of the tree part, modified partial product generation method has been devised at architecture level. This reduces the 4 levels of compression stage to 3 levels, and propagation delay in Wallace tree structure by utilizing 4-2 compressor as well. Furthermore, this enables tree part to be combined with four modular block to construct a CSA tree (carry save adder tree). Therefore, combined with four modular block to construct a CSA tree (carry save adder tree). Therefore, multiplier architecture can be regularly laid out with same modules composed of Booth selectors, compressors and Modified Partial Product Generators (MPPG). At the circuit level new Booth selector with less transistors and encoder are proposed. The reduction in the number of transistors in Booth selector has a greater impact on the total transistor count. The transistor count of designed selector is 9 using PTL(Pass Transistor Logic). This reduces the transistor count by 50% as compared with that of the conventional one. The designed multiplier in 0.25${\mu}{\textrm}{m}$ technology, 2.5V, 1-poly and 5-metal CMOS process is simulated by Hspice and Epic. Delay is 4.2㎱ and average power consumes 1.81㎽/MHz. This result is far better than conventional multiplier with equal or better than the best one published.

• Geotechnical Engineering
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• v.10 no.1
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• pp.47-62
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• 1994

It has been well known that the rainfall-triggered rise of groundwater levels is one of the most important factors resulting the instability of the hillside slopes. Thus, the prediction of porewater pressure is an essential step in the evaluation of landslide hazard. This study involves the development and verification of numerical groundwater flow model for the prediction of groundwater flow fluctuations accounting for both of unsatu나toed flow and saturated flow on steep hillside slopes. The first part of this study is to develop a nomerical groundwater flow model. The numerical technique chosen for this study is the finitro element method in combination with the finite difference method. The finite element method is used to transform the space derivatives and the finite difference method is used to discretize the time domain. The second part of this study is to estimate the unknown model parameters used in the proposed numerical model. There were three parameters to be estimated from input -output record $K_e$, $\psi_e$, b. The Maximum -A-Posteriori(MAP) optimization method is utilized for this purpose, . The developed model is applied to a site in Korea where two debris avalanches of large scale and many landslides of small scale were occurred. The results of example analysis show that the numerical groundwater flow model has a capacity of predicting the fluctuation of groundwater levels due to rainfall reasonably well.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.1
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• pp.96-101
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• 2017

We have developed a compact desktop-sized nanopatterning system driven by the Roll-to-Roll (R2R) nanoimprinting (NIL) principle. The system realizes the continuous and high-speed stamping of various nanoscale patterns on a large-area flexible substrate without resorting to ponderous and complicated instruments. We first lay out the process principle based on continuous NIL on a UV-curable resin layer using a flexible nanopatterned mold. We then create conceptual and specific designs for the system by focusing on two key processes, imprinting and UV curing, which are performed in a continuous R2R fashion. We build a system with essential components and optimized modules for imprinting, UV curing, and R2R conveying to enable simple but effective nanopatterning within the desktop volume. Finally, we demonstrate several nanopatterning results such as nanolines and nanodots, which are obtained by operating the built desktop R2R NIL system on transparent and flexible substrates. Our system may be further utilized in the scalable fabrication of diverse flexible nanopatterns for many functional applications in optics, photonics, sensors, and energy harvesters.

• Atmosphere
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• v.24 no.4
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• pp.481-489
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• 2014

The Chugugi and Wootaek data of Gyeongsang-do (Dagu, Jinju, Goseong) were restored from "Gaksadeungnok", the governmental documents reported by the local government to the central during the Joseon Dynasty, and analyzed. The duration of the restored data represents 6 years for Daegu (1863, 1872, 1890, 1897, 1898, and 1902), 3 years for Jinju (1897, 1898, and 1900), and 2 years for Goseong (1871 and 1873). Total number of the restored data was 134, including 83 in Daegu, 25 in Jinju, and 26 in Goseong with the period ranging from March to September. The summer data from June to August accounts for approximately 50% (73 data), while the April data also shows relatively high number of 22, followed by September and March. Most data was collected from March to October, while this time winter data was not found even in October. The rainfall patterns using Chugugi data were investigated. First, the number of days with rainfall by annual mean showed 41 days in Daegu, 39 in Jinju, 33 in Goseong, respectively. In terms of the time series distribution of daily rainfall, the ratio between the number of occurrences with over 40 mm of heavy rainfall and the number of rainy days showed 14 times (8%) in Daegu, 24 (39%) in Jinju, and 4 (6%) in Goseong, respectively. The maximum daily rainfall during the period was recorded with 80mm in Jinju on August 24, 1900. The result of analyzing monthly amount of rainfall clearly indicated more precipitation in summer (June, July and August) with the relatively high records of 284 mm and 422 mm in April, 1872 and July, 1902, respectively, in Daegu, while Jinju recorded the highest value of 506 mm in June, 1898. When comparing the data with those observed by Chugugi in Seoul during the same period from "Seungjeongwonilgi", the monthly rainfall patterns in Daegu and Seoul were quite similar except for the year of 1890 and 1897 in which many data were missing. In particular, in June 1898 the rainfall amount of Jinju recorded as much as 506 mm, almost 4 times of that of Seoul (134 mm). Based on this, it is possible to presume that there was a large amount of the precipitation in the southern region during 1898. According to the calculated result of Wootaek data based on Chugugi observations, the unit of 1 'Ri' and 1 'Seo' in Daegu can be interpreted into 18.6 mm and 7.8 mm. When taking into consideration with the previous result found in Gyeonggi-do (Cho et al., 2013), 1 'Ri' and 1 'Seo' may be close to 20.5 mm and 8.1 mm, however, more future investigations and studies will be essential to verify the exact values.

• Journal of Distribution Science
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• v.13 no.4
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• pp.77-87
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• 2015

Purpose - This study aims to investigate the current state of distribution terminology usage by retailers and consumers nationwide, and to suggest a practical improvement plan for its standardization. The Korean distribution industry is closely related to consumers' daily lives. However, in reality, there exists a gap among producers, distributors, and consumers in terms of the definition, understanding, and perception of the terminology. Therefore, standardizing this terminology is essential for more smooth communication. This paper suggests the necessity of committing overall research and survey activities to the actual conditions of using Korean distribution terminology by organizations and their respective management situations, and further, the necessity of probing the problem and its measures in line with the objective and mission of the "Fundamental Law of the Korean Language." Research design, data, and methodology - This study's scope is limited to wholesale and retail including some information systems. First, the study covers most written material including lexicons and glossary of distribution terminology, university textbooks and teaching material for national certificate of qualification, and related laws and ordinances. Second, the survey covers retailers' management situations by store format. The retailers used as the sample for the survey include department stores, discount stores, SSM, and convenience stores. Altogether, 20 specialists were interviewed in their respective sectors or retail formats. Finally, the project team surveyed a sample of 1,300 consumers nationwide on 50 distribution terms mainly used by consumers, including those about awareness, understanding, usage, and attitude. Results - In total, 1,249 terms are drawn through literature research including distribution terminology used in the related literature, glossary and lexicons, distribution terminology in textbooks, and legal terminology. A classified table comprises four large categories including general distribution, distribution marketing, distribution information, and merchandise. The results of the three-step research including literature survey, field survey of retailers, and consumer survey were advised to be screened by academia (retail associations, faculty etc.), retailers (major retail management by store format), retail specialists and consultants, consumers, and Korean linguists. In total, 1,300 questionnaires for 50 terms of the distribution terminology closely associated with consumers were distributed to subjects nationwide. Conclusions - The desired and expected results from this study are summarized from three perspectives as follows: First, from retailers' perspective, a new concept, or coinage of new terms of the distribution industry stems from advanced countries such as America and Europe. However, the original meaning and definition are diluted and distorted with changes in the language users' situations and context. This study provides basic guidelines for standardization of distribution terms used among various retail formats in most daily life situations that consumers encounter. Second, from the nation's perspective, this study suggests optimal choices of distribution terminology in the context of laws and ordinances regarding concerned Ministries. Last, from the consumers' perspective, this paper enables consumers to understand and use distribution terms properly in their daily life.

• Journal of Korea Multimedia Society
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• v.1 no.1
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• pp.98-108
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• 1998

In the multimedia tele-medical system the medical informations are stored and managed in multimedia database. Also, multimedia DBMS is essential in order to manage large scale medical informations, and the remote access function is necessary for the distributed processing at all around the hospital. For the multimedia tele-medical information that is composed of image/picture, data, video, and audio, a high-speed telecommunication network is necessary that can provide separated connections for each medical information type with different QoS. The commercial DBMSs are based on the TCP/IP socket API(Application Programming Interface) that does not provide multiple QoS. Also, each commercial DBMS has its own API that is incompatible with other DBMS. In this paper, we propose a multimedia DBMS agent for the remote access of the multimedia database in the tele-medical system. The proposed multimedia DBMS agent is based on the ATM API that can provide high-speed data transfer capability and multiple QoS connections. Also, the proposed multimedia DBMS agent is independent of the commercial DBMS. We explain the functional architecture of the multimedia DBMS agent, implementation technology on the ATM network environment, and the result of performance analysis.