• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.3
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• pp.435-442
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• 2000

The present study is conducted to investigate the local heat/mass transfer characteristics for flow through perforated plates. A naphthalene sublimation method is employed to determine the local heat/mass transfer coefficients on the effusion plate. Two parallel perforated plates are arranged for the two different ways: staggered and shifted in one direction. The experiments are conducted for hole pitch-to-diameter ratios of 6.0, for gap distance between the perforated plates of 0.33 to 10 hole diameters, and for Reynolds numbers of 5,000 to 12,000. The result shows that the high transfer region is formed at stagnation region and at the mid-line of the adjacent impinging jets due to secondary vortices and flow acceleration to the effusion hole. For flows through the perforated plates, the mass transfer rates on the surface of the effusion plate are about six to ten times higher than for effusion cooling alone (single perforated plate). More uniform and higher heat/mass transfer characteristic is obtained in overall region with small gap between two perforated plates.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.89-94
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• 2003

The formation of a severe snow storm occurred in the mountainous coastal region near Mt. Taegualyang and Kangnung city in the eastern part of Korea was investigate from 0900LST, December 7 through 9, 2002, using MM5 model. As synoptic scale easterly wind induced a great amount of moisture from the East Sea into the inland coastal region and sea-breeze further induced more moisture from the basin toward the top of the mountain side. The lifted moisture toward the mountain top was cooled down along the eastern slope of the mountain and near the mid of the mountain the moisture was much cooled down with relative humidity of 100％ under the air temperature below $O^{\circ}C$, resulting in the formation of snow. Relative humidity of 100％ generally occurred at the 5km away from the coast toward the inland mountain and the band of 100％ RH was parallel to the coastal line. The 100％ band coincided with minimum air temperature band and line.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.4
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• pp.357-366
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• 2007

The present study investigated local heat/mass transfer characteristics on the surface of the rotating turbine blade with various incidence angles. The experiments are conducted in a low speed annular cascade with a single stage turbine. The blade has a flat tip with the mean tip clearance of 2.5% of the blade chord. A naphthalene sublimation method is used to measure detailed mass transfer coefficient on the blade. At design condition, the inlet Reynolds number is $Re_c=1.5{\times}10^5$ which results in the blade rotation speed of 255.8 rpm. Also, the effect of off-design condition is examined with various incidence angles between $-15^{\circ}$ and $+7{\circ}$. The results indicated that the incidence angle has significant effects on the blade surface heat transfer. In mid-span region, the laminar separation region on the pressure side is reduced and the laminar flow region on the suction side shrinks with increasing incidence angle. Near the tip, the effect of tip leakage flow increases in span wise and axial directions as the incidence angle decreases because the tip leakage flow is formed near the suction side surface. However, the effect of tip leakage flow is reduced with positive incidence angle.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.84.1-84.1
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• 2014

We report the spatial distribution of early-type stars and pre-main-sequence (PMS) stars around the starburst type young open cluster Westerlund 2. The early-type were selected from UBVI photometric data, while the PMS members were identified from their X-ray emission and mid-infrared excess. The northern clump of the cluster is composed mainly of PMS stars detected in both optical and X-ray and seems to be coeval to the cluster, while PMS stars in the bright bridge region are highly obscured in optical wavelength. The bright bridge appear to be an on-going star forming region possibly triggered by the strong radiation field from both sides-massive stars in Westerlund 2 and WR 20b. We also found that there are many early-type stars not only in the cluster but also farther from the cluster up to several times of the cluster radius. These early-type stars are well aligned from east to southwest of the cluster. We conclude these early-type stars are members of an OB association in the RCW 49 nebula. This report indicates there is a complex star formation history in Westerlund 2 and its surrounding H II region, the RCW 49 nebula.

• SUVANNABHUMI
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• v.9 no.1
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• pp.133-148
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• 2017

In spite of being one of the first countries in Asia to establish an institution devoted to the study of the Asian region, area studies in the Philippines has languished over the years. In contrast, area studies programs of her neighbors have grown by leaps and bounds, invigorated by both public and private support. This observation becomes more glaring as Filipino scholars have made a name for themselves in the field of Southeast Asian Studies abroad. The paper is an appraisal of the current state of Southeast Asian area studies and the extent of its operation by the Philippines' top four universities, namely: the Asian Center of the University of the Philippines, the Ateneo de Manila University, the De La Salle University, and the University of Santo Tomas. Starting from the inception of area studies in the mid-1950s leading to a template patterned after the North American - European model, the paper then describes the challenges and its decline in the 80s toward its progression on a paradigm defined by the growing importance of, and actors within, the region. The paper expresses the view that one, the role of the government was both a boon and a bane in the development of area studies; and two, that the rapid economic growth and immense integration in the region in the last two decades gave a new impetus to Southeast Asian area studies, an enormous opportunity to capitalize on for Philippine universities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.3
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• pp.210-219
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• 2021

In recent years, air temperature has been increasing rapidly compared to the 1980s because of global warming. This increase in temperature reduces the yield and quality of rice; therefore, measures are needed to prevent such effects and ensure food security. The early maturing type (EMT) of rice is mainly cultivated in the central northern mid-mountainous area (CNMA). This study was conducted to shift the transplanting date of EMT and to examine the adaptability of the mid-maturing type (MMT) or mid-late maturing type (MLMT) in the Jecheon region of the CNMA to address global warming. The air temperature increased by 0.7-0.9℃ in the 2010s, compared to that in the 1980s, and was similar to other decades during the ripening period. Over the past 35 years, considering rice quality, the heading date of the Odae variety has arrived sooner by approximately 10 days, the ripened grain ratio has increased by more than 10%, and the thousand grain weight; however, the mean temperature at 40 days after heading has increased by more than 2℃. The late marginal heading date in the Jecheon region was determined as August 11 based on the accumulated temperature of 880℃ and August 15 based on 840℃ for 40 days after heading. According to different transplanting dates, milled rice yield per 10 a was the highest at 567 kg with June 10 in EMT, 595 kg with June 10 in MMT, and 572 kg with May 30 in MLMT. Considering the late marginal heading date, rice yield, and quality, the optimum transplanting date was June 15 in EMT, June 5 in MMT, and May 30 in MLMT in the Jecheon region of CNMA. Owing to global warming, MMT and MLMT are expected to be reliably cultivated in the CNMA.

• Journal of Korea Water Resources Association
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• v.36 no.3 s.134
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• pp.495-505
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• 2003

Convective weather systems such as organized mesoscale convective systems (Mesoscale Convective Complex, MCC and Convective Cloud Clusters, CCC) and much weaker Disorganized Short-lived Convection (DSC) in the region of India and Nepal were analyzed using the Meteosat-5 IR imagery. The diurnal march and propagation of patterns of convective activity in the Himalayas and Northern Indian subcontinent were examined. Results indicate that infrared satellite images of Northern India and along the southern flank of the Himalayas reveal a strong presence of convective weather systems during the 1999 and 2000 monsoons, especially in the afternoon and during the night. The typical MCCs have life-times of about 11 hours, and areal extent about $300,000km^2$. Although the core of MCC activity remains generally away from the Middle Himalayan range, the occurrence of heavy precipitation events in this region can be directly linked to MCCs that venture into the Lesser Himalayan region and remain within the region bounded by $25^{\circ}-30^{\circ}N$. One principal feature in the spatial organization of convection is the dichotomy between the Tibetan Plateau and the Northern Indian Plains: CCCs and DSCs begin in the Tibetan Plateau in the mid-afternoon into the evening; while they are most active in the mid-night and early morning in the Gangetic Plains and along the southern facing flanks of the Himalayas. Furthermore, these data are consistent with the daily cycle of rainfall documented for a network of 20 hydrometeorological stations in Central Nepal, which show strong nocturnal peaks of intense rainfall consistent with the close presence of Convective Weather Systems (CWSs) in the Gangetic Plains (Barros et al. 2000).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.166-171
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• 2017

For high-quality colored rice production, the cultivation environment is a critical factor. The major environmental factor is temperature, which includes the accumulated and average temperature during vegetative and reproductive stages. Generally, during the cultivation period, the temperature can be controlled by shifting the transplanting date. This study was carried out to determine the optimum transplanting date for high-quality red-colored rice production. Four red-colored rice varieties (Jeokjinju, Jeokjinjuchal, Hongjinju, and Gunganghongmi) were used as test materials. The transplanting dates were May 20 and June 5, 20, and 30 in 2015~2016. The most variable factor controlled by the transplanting date was the grain filling rate. The varieties transplanted on June 30 showed low yields owing to the decrease in the grain filling rate. In contrast, the polyphenol content increased with increasing delay in the transplanting date. Collectively, these two results indicate that the optimum transplanting date was June 20. The average temperature for 30 days after the heading date (30DAH) highly affected the polyphenol content. A lower temperature during the 30DAH induced higher polyphenol contents but also caused low yield. The optimum 30DAH temperature for obtaining a higher yield and polyphenol content was $22{\sim}23^{\circ}C$. Using the average 30DAH and accumulated temperatures, the optimum transplanting date was calculated as June 18 to 24 in Miryang region. The optimum transplanting date of Kyeungsangnamdo region was approximately mid-June to early July, and that of Kyeungsangbukdo region was approximately early to mid-June.

• Cross-Cultural Studies
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• v.22
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• pp.203-221
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• 2011

With the beginning of systemized research on Latin American region as a part of the third world in the mid-60s, Latin American regional studies in Korea acquired a steppingstone for development through the establishment of Hankook University of Foreign Studies Central & South American Regional Study, the creation of Central & South America Research Center, and Latin American Society established in the mid-80s. Latin American regional studies achieved quantitative and qualitative growth with the natioal globalization policy in the 90s, and research centers related to Latin America in Seoul National University, Pusan University of Foreign Studies, Dankook University, and Sunmoon University have contributed to the activation of regional studies. In spite of such achievements, Latin American regional studies, which have developed with 40 years of history, still possess problems that need to be solved. This study achieves qualitative analysis on theses published from 2000 to March 2001 in main Latin America regional study academic journals in Korea to analyze Latin American regional study trend of the recent 10 years in order to search measures for activating Latin American regional studies. Academic journals used in analysis include "Ibero America Research" of Seoul National University Research Center of Central & South America, Spain, "Central & South America Research" of Hankook University of Foreign Studies Research Center of Central & South America, "Ibero America Research" of Pusan University of Foreign Studies Central & South America Center, and "Latin America Research" published by Latin American Society. According to analysis on publication ratio of published theses according to field, it was presented that culture and politics fields occupied the highest ratio. Social and cultural fields, the elementary studies of regional research which have previously presented a weak research tendency, have achieved noticeable development during the past 10 years. According to analysis on researched nations, Latin America regional study was weighted in particular nations, and nations of economic size and political influence within region were selected as main subjects of research. Furthermore, several nations were not researched at all. For the last 10 years, the depth and width of the Latin America regional study had been decided by the degree of political, economic, social, and cultural significance occupied by the nation. It can be said that studies based on overall understanding on regional countries of Latin America have been relatively weak in individual nation study. Furthermore, studies that separate issues to achieve analysis based on the awareness theory of individual branches can be regarded dominant among studies based on entire Latin America. These studies still possess limitations in failing to deviate from the outline of particular region and topic.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.217-218
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• 2012

Among the AKARI all-sky survey data, the $9{\mu}m$ diffuse map is crucial to study the polycyclic aromatic hydrocarbon (PAH) emission features on large spatial scales, while the $18{\mu}m$ map is useful to trace hot dust emission. To utilize these advantages, we have improved the AKARI mid-infrared (MIR) all-sky survey diffuse maps. For example, we have established special methods to remove the effects of the ionizing radiation in the South Atlantic Anomaly (SAA) and of the scattered light from the moon. Using improved diffuse map data, we study the properties of PAHs and dust in the Galactic center region associated with high-energy phenomena.