• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.353-353
• /
• 2017

Rice yield of South Korea in 2015 was the highest of the last 30 years. It is important issue to establish food policy whether the historically highest yield in 2015 can be continued or just one-off event. Therefore, it is necessary to understand whether such a high yield as 2015 will be reoccurred. The aim of this study was to find out what climatic factor affect rice yield and how often these climatic factor could occur. For this study, the yield monitoring data from National Institute of Crop Science, Rural Development Administration and the meteorological data provided by Korea Meteorological Administration are used to identify the weather conditions could cause high yield, and how often these conditions occurred in the past. Our results indicated that such as high yield as 2015 could occur only when the mean sunshine hours of July and the mean sunshine hours from the end of August to early September was more than 5.1 hours and 6 hours, respectively. Mean sunshine hour of July may be related to grain number. The mean sunshine hour from the end of August to early September was presumed to relate to grain filling ratio. The relationship between monthly mean temperature and yield or yield component was not clear in this study. In this study, any cycle of high weather condition was not found. Therefore, the probability of high yield weather condition was expressed by frequency. The frequency of the sunshine hour, could make high yield, were 8/35 (23%) over the past 35 years. And the frequency of two years consecutive sunshine hour condition, which could cause high yield, was 1/35 (2.9%). The frequency of recurrence of sunshine hour making high yield within the next 5 years or 10 years after high yield weather condition were 4/35 (11.4%). After all, the high yield as much as yield of 2015 could not be one-off event. But it was not also consecutive event.

• Korean Journal of Pharmacognosy
• /
• v.51 no.4
• /
• pp.244-254
• /
• 2020

Atractylodes macrocephala is a perennial herb and is a member of the Compositae family. This plant is known to contain various bioactive constituents indicating anti-inflammatory, neuroprotective, anti-oxidant, immunological enhancement, and gastroprotective effects. In this investigation, we isolated four compounds with similar chemical structures from A. macrocephala, and evaluated their anti-inflammatory effects. Among the four compounds, compound 2(atractylenolide II) showed the second-best inhibitory effect on the lipopolysaccharide(LPS)-induced production of nitric oxide in RAW264.7 macrophages and BV2 microglial cells. Compound 2 also inhibited the LPS-induced the production of prostaglandin E2(PGE2), and the expression of inducible nitric oxide synthase(iNOS) and cyclooxygenase(COX)-2 proteins in both cells. In addition, compound 2 suppressed the production of pro-inflammatory cytokines including interleukin(IL)-1β, IL-6, and tumor necrosis factor(TNF)-α. These inhibitory effects were contributed by inactivation of nuclear factor kappa B(NF-κB) and mitogen-activated protein kinases(MAPKs) pathways by treatment with compound 2. This compound did not induce the expression of heme oxygenase(HO)-1 protein indicating that the anti-inflammatory effect of compound 2 was independent with HO-1 protein. Taken together, these results suggested that atractylenolide II can be a candidate material to treat inflammatory diseases.

• Korean Journal of Culture and Social Issue
• /
• v.19 no.2
• /
• pp.133-158
• /
• 2013

The present research aimed at investigating the impacts of volunteer activities on self-development and sociability-development. In study 1, the scale comprised of 15 items was developed to measure the meaningfulness of volunteer activities. An exploratory factor analysis was conducted on the data obtained from 428 undergraduates (193 males and 235 females). A confirmatory factor analysis was then conducted on the data obtained from 280 undergraduates (124 males and 156 females). In study 2, the impacts of volunteer activities on 947 undergraduates (461 males and 486 females) were analyzed in terms of self-development and sociability-development. Self-development consisted of self-evaluation, self-esteem, and quality of life. Sociability-development consisted of pother-acceptances, sense of community, and democratic citizenship. The results showed that not more volunteer activities itself but more meaningfulness of those activities had stronger relations with self-development and sociability-development. Finally, a values of the undergraduates internalized for volunteer activities and their levels of self-development and sociability-development expectation were discussed.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.625-627
• /
• 2002

High precision voltages. currents. power factor and electrical power measurements wide range of frequency can be achieved by using the thermo-elements (thermal converters). This paper describes the development wattmeter. based on a thermal principle. The instrument has been performed measurement in the range of currents from 0 to 50 A, voltages up to 600 V, power factor 0.5. 1 and frequencies from 45 Hz to 3 kHz. The thermal converters with two heater are used in the functional element of the wattmeter.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.23 no.6
• /
• pp.886-897
• /
• 1999

Fitness of clothes becomes a major concern in apparel industry. But girls had difficulties to buy ready-made clothes of good fit. To solve this problem it is necessary to classify girls' lower body Into several kinds of somatotypes and to develop dress form. The purposes of this study was to classify lower body types of middle-high school an provide the dress forms based on the analysis of their lower body types. The subjects for anthropometric measurement were 402 middle-high school girls of 13 to 15 year-old. The result of factor analysis indicated that 5 factors were extracted from anthropometric measurments through factor analysis and those factors comprise 71% of total variance. 4 clusters were categorized using 5 factor scores by cluster analysis 4 lower body dress forms for middle-high school girls were made of gypsum mould. By the analysis of more photograph three dimensional characteristics of somatotype and overlapped cross-section diagrams were analyzed.

• Journal of Power Electronics
• /
• v.15 no.3
• /
• pp.644-651
• /
• 2015

This paper introduces a novel digital one cycle control (DOCC) boost power factor correction (PFC) converter. The proposed PFC converter realizes the FPGA-based DOCC control approach for single-phase PFC rectifiers without input voltage sensing or a complicated two-loop compensation design. It can also achieve a high power factor and the operation of low harmonic input current ingredients over universal loads in continuous conduction mode. The trailing triangle modulation adopted in this approach makes the acquisition of the average input current an easy process. The controller implementation is based on a boost topology power circuit with low speed, low-resolution A/D converters, and economical FPGA development board. Experimental results demonstrate that the proposed PFC rectifier can obtain a PF value of up to 0.999 and a minimum THD of at least 1.9% using a 120W prototype.

• Biomolecules & Therapeutics
• /
• v.23 no.1
• /
• pp.12-18
• /
• 2015

Skin is an emerging target tissue in pharmaceutical and cosmetic science. Safety assessment for dermal toxicity is a critical step for development of topically applicable pharmaceutical agents and ingredients in cosmetics. Urgent needs exist to set up toxicity testing methods for dermal safety, and identification of novel biomarkers for pathological cutaneous alteration is highly required. Here we will discuss if vascular endothelial growth factor (VEGF) has a potential as a biomarker for dermal impairment. Experimental and clinical evidences for induction of keratinocytic VEGF under pathological conditions will be reviewed.

• Steel and Composite Structures
• /
• v.18 no.1
• /
• pp.71-90
• /
• 2015

Axial compression tests have been carried out on 18 rectangular concrete-filled cold-formed steel tubular (CFST) columns with the aim of investigating the axial behaviour of rectangular CFST columns under different loading methods (steel loaded-first and full-section loaded methods). The influence of different loading methods on the ultimate strength of the specimens was compared and the development of Poisson's Ratio as it responds to an increasing load was reported and analysed. Then, the relationship between the constraining factor and the strength index, and the relationship between the constraining factor and ductility index of the specimens, were both discussed. Furthermore, the test results of the full-section loaded specimens were compared with five international code predicted values, and an equation was derived to predict the axial carrying capacity for rectangular CFST columns with a steel loaded-first loading method.

• ETRI Journal
• /
• v.30 no.1
• /
• pp.81-88
• /
• 2008

The security threat posed by worms has steadily increased in recent years. This paper discusses the application of the optimal and sub-optimal Internet worm control via Pontryagin's maximum principle. To this end, a control variable representing the optimal treatment strategy for infectious hosts is introduced into the two-factor worm model. The numerical optimal control laws are implemented by the multiple shooting method and the sub-optimal solution is computed using genetic algorithms. Simulation results demonstrate the effectiveness of the proposed optimal and sub-optimal strategies. It also provides a theoretical interpretation of the practical experience that the maximum implementation of treatment in the early stage is critically important in controlling outbreaks of Internet worms. Furthermore, our results show that the proposed sub-optimal control can lead to performance close to the optimal control, but with much simpler strategies for long periods of time in practical use.

• 한국디지털정책학회:학술대회논문집
• /
• 2006.12a
• /
• pp.167-175
• /
• 2006

This paper aimed to exam core factors of the success factors of new products and analyze their effects on success. To accomplish this purpose, this study examined previous studies and summarized core factors of success factors of new products. From previous studies, we drawed core factor Core factor is technology factors(marketing skills, technical skills), specific of new product(more innovative, less innovative, cost advantage, competitive advantage), the process of product development(crossfunctional integralion, staff involvement). Except for more innovative factors, the others factors affect on success To be winner , companies must be consider these key factor( less innovative, cost advantage, competitive, advantage, cross-functionalintegration, staff involvement)