• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.391-404
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• 2021

This study developed a long-term prediction model for the potential yield of garlic based on a genetic algorithm (GA) by utilizing global climate reanalysis data. The GA is used for digging the inherent signals from global climate reanalysis data which are both directly and indirectly connected with the garlic yield potential. Our results indicate that both deterministic and probabilistic forecasts reasonably capture the inter-annual variability of crop yields with temporal correlation coefficients significant at 99% confidence level and superior categorical forecast skill with a hit rate of 93.3% for 2 × 2 and 73.3% for 3 × 3 contingency tables. Furthermore, the GA method, which considers linear and non-linear relationships between predictors and predictands, shows superiority of forecast skill in terms of both stability and skill scores compared with linear method. Since our result can predict the potential yield before the start of farming, it is expected to help establish a long-term plan to stabilize the demand and price of agricultural products and prepare countermeasures for possible problems in advance.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.2
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• pp.65-75
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• 2010

Space transformation of hospital architecture happens more rapidly than other types such as school and office buildings. This requirement is caused by medical demand, service transformation, technical development and equipment changes. Grand scale extension and rapid change in hospital architecture affects whole planning; therefore, it is important to design in the macro perspective such like Life Cycle. Grand scale extension is difficult process to rebuild growth and transfer of hospital architecture and to adapt to the future change. That's why simple planning gives limits to some departments in a short-term and brings another reform such as more extension or interior renovation in a long-term. This study surveys various space transformation and grand scale extension of EB hospital extended recently, and it is to find planning condition in extension.

• Journal of Climate Change Research
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• v.9 no.2
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• pp.143-156
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• 2018

Evapotranspiration is a key element in designing and operating agricultural hydraulic structures. The profound effect of climate change to local agro-hydrological systems makes it inevitable to study the potential variability in evapotranspiration rate in order to develop policies on future agricultural water management as well as to evaluate changes in agricultural environment. The APEX-Paddy model was used to simulate local evapotranspiration responses to climate change scenarios. Nine Global Climate Models(GCMs) downscaled using a non-parametric quantile mapping method and a Multi?Model Ensemble method(MME) were used for an uncertainty analysis in the climate scenarios. Results indicate that APEX-Paddy and the downscaled 9 GCMs reproduce evapotranspiration accurately for historical period(1976~2005). For future periods, simulated evapotranspiration rate under the RCP 4.5 scenario showed increasing trends by -1.31%, 2.21% and 4.32% for 2025s(2011~2040), 2055s(2041~2070) and 2085s(2071~2100), respectively, compared with historical(441.6 mm). Similar trends were found under the RCP 8.5 scenario with the rates of increase by 0.00%, 4.67%, and 7.41% for the near?term, mid?term, and long?term periods. Monthly evapotranspiration was predicted to be the highest in August, July was the month having a strong upward trend while. September and October were the months showing downward trends in evapotranspiration are mainly resulted from the shortening of the growth period of paddy rice due to temperature increase and stomatal closer as ambient $CO_2$ concentration increases in the future.

• Atmosphere
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• v.25 no.2
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• pp.249-260
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• 2015

The changes in thermodynamic and dynamic aspects on near (2025~2049) and long-term (2075~2099) future climate changes between the historical run (1979~2005) and the Representative Concentration Pathway (RCP) 4.5 run with 20 coupled models which employed in the phase five of Coupled Model Inter-comparison Project (CMIP5) over East Asia (EA) and the Korean Peninsula are investigated as an extended study for Moon et al. (2014) study noted that the 20 models' multi-model ensemble (MME) and best five models' multi-model ensemble (B5MME) have a different increasing trend of precipitation during the boreal winter and summer, in spite of a similar increasing trend of surface air temperature, especially over the Korean Peninsula. Comparing the MME and B5MME, the dynamic factor (the convergence of mean moisture by anomalous wind) and the thermodynamic factor (the convergence of anomalous moisture by mean wind) in terms of moisture flux convergence are analyzed. As a result, the dynamic factor causes the lower increasing trend of precipitation in B5MME than the MME during the boreal winter and summer over EA. However, over the Korean Peninsula, the dynamic factor causes the lower increasing trend of precipitation in B5MME than the MME during the boreal winter, whereas the thermodynamic factor causes the higher increasing trend of precipitation in B5MME than the MME during the boreal summer. Therefore, it can be noted that the difference between MME and B5MME on the change in precipitation is affected by dynamic (thermodynamic) factor during the boreal winter (summer) over the Korean Peninsula.

• Journal of Korean Society of Forest Science
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• v.94 no.4 s.161
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• pp.252-257
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• 2005

The study on long-term change of natural and sediment disasters such as landslides and debris flows is not thoroughgoing enough in spite of increasing of concern for disaster. Therefore, the change of natural and sediment disasters was investigated with the number of victims caused by both disasters and the ratio of sediment disasters for natural disasters was compared. The number of victims by sediment and natural disasters has apparently been decreasing despite of the change of rainfall pattern. The number of victims was changed to 140 persons/year in the late 1990s from 250 persons/year in the 1970s of natural disaster and that of sediment disaster to 20 persons/year in the late 1990s from 60 persons/year in the late 1970s. Furthermore, the ratio of sediment disaster victims to natural disaster victims has decreased from 2/7 in the 1970s to 2/15 after 1980s. But, the system of sediment disaster management and new soil erosion control works tough introduction of watershed management concept are requested because of increased landslide area in recent years (206ha in 1981 $\rightarrow$ 688ha in 1999).

• Journal of Climate Change Research
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• v.8 no.2
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• pp.109-123
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• 2017

The effects of recent climate change on hydrological systems could affect the Winter Olympic Games (WOG) because the event is dependent on suitable snow and ice conditions to support elite-level competitions. We investigate the long-term variability and change in winter total precipitation (P), snowfall water equivalent (SFE), and ratios of SFE to P during the period 1973/74~2015/16 in Gangwon province. The climatological percentages of SFE relative to winter total precipitation were 71%, 28%, and 44% in Daegwallyeong, Chuncheon, and Gangneung, respectively. The winter total P, SFE, and SFE/P has decreased (but not significantly), although significant increases of winter maximum and minimum temperature were detected at a 95% confidence level. Notably, a significant negative trend of SFE/P at Daegwallyeong in February, the month of the WOG, was attributable to a larger decrease in SFE related to the increases in maximum and minimum temperature. Winter wet-day minimum temperatures were warmer than climatological minimum temperatures averaged over the study period. The 20-year return values of daily maximum P and SFE decreased in Yongdong area. Since the SFE/P decrease with increasing temperature, the probability of rainfall rather than snowfall can increase if global warming continues.

• Korean Journal of Labor Studies
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• v.24 no.1
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• pp.1-28
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• 2018

This paper studies and evaluates the present situation of three decades of 'Minjoonojoundong' in Korea with a long-term perspectives. It had grown up during 1987 labour regime era and has declined abruptly since 1998. The backdrop of this decline was the transformation of labour regime from the 1987 regime to the dependent neoliberal one. The Korean labour movement did not respond to the changed structural conditions as it sustained its old strategies, militant unionism. Now the 'Minjoonojoundong' in Korea has met three difficult problems that are connected with each others. They are militant economism, political economism and formal industrial unionism. However the 'Candlelight Revolution' occurred in 2016 winter has opened a chance of regime change that could strengthen the 'Minjoonojoundong'. The revolution was primarily a political one. But it also created a dramatic situation change in labour politics. The candle-citizen demanded radical change of the polarized Korean society and overflown contingent workers. So it is a time of radical and overall innovation for the 'Minjoonojoundong' and KCTU. And they have to keep the long-term strategical vision of labour regime change.

• Korean Journal of Radiology
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• v.21 no.11
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• pp.1248-1255
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• 2020

Objective: To analyze long-term follow-up sonographic findings of intrathyroidal thymus in children. Materials and Methods: Among 1259 patients with congenital hypothyroidism under 15 years of age who underwent thyroid ultrasonography (US), 41 patients were diagnosed with an intrathyroidal thymus based on US criteria, i.e., hypoechoic solid lesion with punctate and linear echogenicity. In 26 patients aged one to 14 years old, the last follow-up US was performed after 6 to 132 months and compared with the initial US. The lesion was considered to decrease in size if there was a change of more than 2 mm in any dimension. The margin change was divided into well-defined and indistinct, blurred. When the echogenicity changed to a hyperechoic from a characteristic thymic echogenicity pattern, the pattern was considered a hyperechogenic. The changes in size were compared with the changes in shape, margin, and echogenicity pattern. The changes in size, shape, margin, and echogenicity were analyzed the association with the age of last follow-up. Statistical analysis was conducted using the chi-squared test and logistic regression. Results: Fifteen (57.7%) cases were stable in size, and 11 (42.3%) decreased in size, including one that disappeared. Ten (38.5%) cases changed to indistinct margins from initially well-defined margins including one case of initially indistinct margin. Six (23.1%) changed to hyperechogenic, from initially characteristic thymic echogenicity patterns. When follow-up change was compared, decreases in size were significantly associated with lesion changes to indistinct margins (p = 0.004). The age at last follow-up was significantly associated with change to hyperechogenicity (odd ratio, 2.141; 95% confidence interval, 1.144-4.010, p = 0.017). Conclusion: On follow-up US, an intrathyroidal thymus may be decreased in size, with indistinct margins, or show changes to a hyperechoic mass. Decreases in size may be associated with changing to indistinct margins, and changes to hyperechogenicity may be associated with increasing age.

• The Korean Journal of Financial Management
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• v.24 no.1
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• pp.1-27
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• 2007

In this study, we investigated the market long-term performance of stock splits by using the Korean Stock Market data from 1998 through 2002. We measured the performance by the event-time portfolio approach with the buy-and-hold abnormal return(BHAR) and the cumulative average abnormal return(CAAR). Also, the calendar-time portfolio approach with one-factor and three factor model were used for avoiding the misspecification model problem. The first of main results in this study was that the stock splits had significantly positive abnormal returns around the month of the stock splits announcements. However, the period BHAR and CAAR after the announcement month were significantly negative. This negative long-term abnormal returns were confirmed by the calendar-time portfolio approach. The results suggested that the abnormal return followed by the stock splits seemed to be positive in the short-term period. Second, there was no the difference of the long term performance between the high and the low split ratios. The operating income performance in the periods followed by the stock splits announcements grew worse. Therefore, the signalling effects, the managers of the firm under considering the stock splits would make use of splits as a form of signals for the upward changes in the cash flow or profits, could not be found. Finally, in contrast to Fama, Fisher, Jensen and Roll(1969), the significant negative abnormal returns following the stock splits were still found irrespective of the change of dividend payout ratio.

• Journal of the Korean association of regional geographers
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• v.15 no.2
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• pp.282-291
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• 2009

This research predicts the spatial discord which relates with a restriction using 1915 and 2005 spatial data. In this research, difference of relative spatial density is measured and predicted the discord which relates with an environmental restriction in Pyeongchang. First, research area Pyeonchang's relative crowding degree of the building was strengthened from 1915 to 2005. When classifies a change type, formed the strong hold with new regulation and grew types and at the strong hold where contiguous concentration is progress types, general the influence weakening types and the change almost nil types. The next is the result which analyzes the long and short terms discord for the environmental restriction which is forecast from the research area. That is forecast with the fact that the discord between of development and preservation will be big with long and short terms in Jinbu-Myeon, Pyeongchang-Eup city center angles and 31 national road circumferences. And in Daegwanryeong-Myeon the discord is big short-term but with the fact that the discord will be weakened long-term. Bangrim-Myeon, now the discord is weak but the discord will be strengthened long-term. This result could be applied with fundamental data for weakening the spatial discord of the area.