• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.4
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• pp.293-303
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• 2017

The purpose of this study is to measure the effects of droughts and public investments in irrigation facilities on rice production. We estimated the effects of droughts and the fraction of irrigated paddy fields with irrigation facilities on rice yields through a panel regression model. The results showed that the effect of drought on rice yield was negative but modest. Also, we found that increases in the ratio of irrigated paddy fields to total paddy fields by 1% enhance rice yields by 0.025-0.035%. However, the ratio of irrigated paddy fields to total paddy fields has insignificant effects on reducing harmful droughts effects regardless of the conditions of irrigated paddy fields.

• Knowledge Management Research
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• v.20 no.3
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• pp.155-171
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• 2019

In the entertainment industry which has great uncertainty, it is essential to predict public preference first. Thanks to various mass media channels such as cable TV and internet-based streaming services, the reality audition program has been getting big attention every day and it is being used as a new window to new entertainers' debut. This phenomenon means that it is changing from a closed selection process to an open selection process, which delegates selection rights to the public. This is characterized by the popularity of the public being reflected in the selection process. Therefore, this study aims to implement a machine learning model which predicts the winner of , which has recently been popular in South Korea. By doing so, this study is to extend the research method in the cultural industry and to suggest practical implications. We collected the data of winners from the 1st, 2nd, and 3rd seasons of the Produce 101 and implemented the predictive model through the machine learning method with the accumulated data. We tried to develop the best predictive model that can predict winners of by using four machine learning methods such as Random Forest, Decision Tree, Support Vector Machine (SVM), and Neural Network. This study found that the audience voting and the amount of internet news articles on each participant were the main variables for predicting the winner and extended the discussion by analyzing the precision of prediction.

• Korean Journal of Radiology
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• v.21 no.1
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• pp.117-117
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• 2020

• Journal of the Korea Society for Simulation
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• v.33 no.1
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• pp.1-17
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• 2024

Forest management is known to beneficially influence stand structure and wood production, yet quantitative understanding as well as an illustrative depiction of the effects of different management approaches on tree growth and stand dynamics are still scarce. Long-term management of beech forests must balance public interests with ecological aspects. Efficient forest management requires the reliable prediction of tree growth change. We aimed to develop a novel hybrid simulation approach, which realistically simulates short- as well as long-term effects of different forest management regimes commonly applied, but not limited, to German low mountain ranges, including near-natural forest management based on single-tree selection harvesting. The model basically consists of three modules for (a) natural seedling regeneration, (b) mortality adjustment, and (c) tree growth simulation. In our approach, an existing validated growth model was used to calculate single year tree growth, and expanded on by including in a newly developed simulation process using calibrated modules based on practical experience in forest management and advice from the local forest. We included the following different beech forest-management scenarios that are representative for German low mountain ranges to our simulation tool: (1) plantation, (2) continuous cover forestry, and (3) reserved forest. The simulation results show a robust consistency with expert knowledge as well as a great comparability with mid-term monitoring data, indicating a strong model performance. We successfully developed a hybrid simulation that realistically reflects different management strategies and tree growth in low mountain range. This study represents a basis for a new model calibration method, which has translational potential for further studies to develop reliable tailor-made models adjusted to local situations in beech forest management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3220-3230
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• 2014

This paper analyzes the house designs of Kazuyo Sejima and Ryue Nishizawa from the 1900s to the early 2000s' works. By analyzing the degree of space integration of each house using the Convex Map of the Space Syntax Theory, this study arrived at the following conclusions in the respects of private space and public space. First, from period 1 (the 1990s) to period 2 (the first half of the 2000s), the differences between average integration values of private space and public space in their works have decreased. Over time, in general, average integration values of private space have increased, and, on the other hand, those of public space have decreased, leading to smaller differences between two sets of values, which means that, as the integration degrees of private and public spaces have become similar, the boundary which divides spaces becomes blurry. Second, in terms of private space, average integration values of private space in S-3 (House in a Plum Grove) and S-4 (House in China), works of period 2, are the highest among those values of their all 10 works. We can identify that, closure degrees of private space in their works have fallen over time. Third, in terms of public space, average integration values of I-2 (Villa in the Forest), I-5 (S-House), and I-6 (Weekend House), works of period 1, are the highest among those values of their all 10 works. Public space has become more central and open from period 1 to period 2.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.4
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• pp.13-20
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• 2013

Due to the global warming, international agreements have been propelled by industrialized countries. These days, there are various studies and projects to reduce the carbon emission quantity in South Korea, because South Korea is a strong candidate for a newly industrialized nation by Kyoto Protocol. Therefore, this study arranges plans to create various thematic map by producing database that can manage various datum based on grid spatial objects to manage quantity of forest biomass and carbon dioxide. Moreover, this study designs a system to create forest biomass by using the best method of calculation with LiDAR data and KOMPSAT-2 satellite images. In addition, this study designs a biomass monitoring system for public institutions to register biomass, suggesting actual plans to extract, manage, and utilized forest biomass.

• Journal of Korean Society of Forest Science
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• v.31 no.1
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• pp.21-29
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• 1976

In foreign countries the national forests began to emerge when the modern body politic came into being and looked upon forests as an indispensible source of national wealth to the effect that eachnation virtually nationalized the forests to promote the public interest such as erosion prevention and water source stability. Most of the forests that are now in national ownership used to be the estates of kings and feudal lords in the Middle Ages. In Korea in national forests come into being toward the end of Yi-dynasty as an outcome of the Japanese colonial policy under which, with the purpose of exploiting the forest resources, the dense forests of large area were systematically transferred into national property to be controlled by establishing the echelon of the national forest stations. The main task of these stations was to fell lumber to no limits.

• Journal of Ecology and Environment
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• v.34 no.2
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• pp.203-214
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• 2011

The objectives of this research were to predict land-use/land-cover change at the Sakaerat Environmental Research Station (SERS) and to analyze its consequences on the distribution for Black-crested Bulbul (Pycnonotus melanicterus), which is a popular species for bird-watching activity. The Dyna-CLUE model was used to determine land-use allocation between 2008 and 2020 under two scenarios. Trend scenario was a continuation of recent land-use change (2002-2008), while the integrated land-use management scenario aimed to protect 45% of study area under intact forest, rehabilitated forest and reforestation for renewable energy. The maximum entropy model (Maxent), Geographic Information System (GIS) and FRAGSTATS package were used to predict bird occurrence and assess landscape fragmentation indices, respectively. The results revealed that parts of secondary growth, agriculture areas and dry dipterocarp forest close to road networks would be converted to other land use classes, especially eucalyptus plantation. Distance to dry evergreen forest, distance to secondary growth and distance to road were important factors for Black-crested Bulbul distribution because this species prefers to inhabit ecotones between dense forest and open woodland. The predicted for occurrence of Black-crested Bulbul in 2008 covers an area of 3,802 ha and relatively reduces to 3,342 ha in 2020 for trend scenario and to 3,627 ha for integrated-land use management scenario. However, intact habitats would be severely fragmented, which can be noticed by total habitat area, largest patch index and total core area indices, especially under the trend scenario. These consequences are likely to diminish the recreation and education values of the SERS to the public.

• Proceedings of the KSRS Conference
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• v.2
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• pp.590-593
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• 2006

Timber inventory management includes to measure and update forest attributes, which is crucial information for private companies and public organizations in property assessment and environment monitoring. Field measurement would be accurate, but time-consuming and inefficient. For the reason, remote sensing technology has been an alternative to field measurement from an economic perspective. Among several sensors, LiDAR and Radar interferometry are known for their efficiency for forest monitoring because they are less influenced by weather and light conditions, and provide reasonably accurate vertical/horizontal measurement for a large area in a short period. For example, Shuttle Radar Topography Mission (SRTM) and National Elevation Dataset (NED) in the U.S. can provide tree height information and DSM. On the other hand, LiDAR DSM (the first return) and DEM (the last return) can also present tree height estimation. With respect to project site of loblolly pine plantation in Louisiana in the U.S., the accuracy of SRTM C-Band approach estimating tree height was assessed by the LiDAR approaches. In addition, SRTM X-Band and NED were also compared with the results. Plantation year in inventory GIS, which is directly related to forest age, is high correlated with the difference between SRTM C-Band and NED. As a byproduct, several stands of age mismatch could be recognized using an outlier detection algorithm, and optical satellite image (ETM+) were used to verify the mismatch. The findings of this study were (1) the confirmation of usefulness of the SRTM DSM for forest monitoring and (2) Multi-sensors- Radar, LiDAR, ETM+, MODIS can be used for accuracy improvement of forest inventory GIS altogether.

• Journal of the Korean Wood Science and Technology
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• v.26 no.3
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• pp.81-92
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• 1998

Lately public interest in tree saps of maple and birch trees has been increased for sap drink as a natural medical beverage. To ensure tree sap drink for commercial production, species which are available in resources, their ecological regeneration characteristics in the natural forest stand, and tree sap resources should be investigated. Species for the collecting tree saps and their distribution were surveyed in the areas of Mt.Sobaek, Tanyang-gun, Chungcheongbuk-do. Mt.Sobaek area was selected to the proper place to survey as the feasible area for tapping tree saps for the natural beverage. Feasible tree species of this area are Betula costata, Betula schmidtii, Comus controversa, Acer mono, and Acer pseudosieboldianum based on the estimated tree sap amounts. Average and maximum species diversities of surveyed area were 4.2 and 5.39, respectively. Its evenness 0.78 referred that there are actively progressing ecological regeneration among diverse tree species. Tree saps are mainly harvested at the areas of upper and lower Wonmanteo. In terms of species, the most high sap amounts were from birch sap, next Comus controversa, the 3rd Acer mono. Many measures were suggested ecologically and technically, for commercial or practical production of tree sap drinks, though Mt.Sobaek area was evaluated as improper place because of geographical and transportational limitation.