• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.9-24
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• 2009

We compare the relation among the annual distribution of sunspots: coronal mass ejections (CMEs) and geomagnetic storms and North-South asymmetry during solar cycle 23. For this purpose, we calculate correlation coefficients between (i) annual distribution and N-S asymmetry of CMEs - sunspots (ii) distribution of CMEs - occurrence number of geomagnetic storms (iii) distribution of sunspots - occurrence number of geomagnetic storms. We find that (i) the annual distribution of total CMEs has good correlation with distribution of annual average of sunspots but poor correlation with N-S asymmetry of sunspots, N-S asymmetry of CMEs has good correlation with N-S asymmetry of sunspots: (ii) total and N-S asymmetry of CMEs have poor correlation with occurrence number of geomagnetic storms, it's, however, well correlated with the classified groups of CMEs (Ap, Dst and an indices vs. fast CMEs($\upsilon$ > $1000kms^{-1}$), Dst index vs. Halo CMEs), and (iii) sunspot numbers and area are correlated with occurrence number of geomagnetic storms. We conclude that annual distribution of CMEs and sunspots have well correlated with geomagnetic storms, N-S asymmetry of CMEs and sunspots have poor correlated with the geomagnetic storms.

• The Bulletin of The Korean Astronomical Society
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• v.34 no.1
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• pp.79.2-79.2
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• 2009

• Bulletin of the Korean Space Science Society
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• 2009.04a
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• pp.42.1-42.1
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• 2009

• The Korean Journal of Quaternary Research
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• v.5 no.1
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• pp.33-45
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• 1991

Sand bars associated with strong tidal currents are well developed in the subtidal zone near the Kokunsan islands. Tidal currents measured at sand bar in the area show an asymmetry in magnitude between flood and ebb currents. At the southern flank of the sand bar the currents are flood-dominant whereas the currents are ebb-dominant at the northern flank. The asymmetry is more distinctive as the currents become stronger during spring tide. Moreover, the flood-dominance along the southern flank is stronger than the ebb-dominance along the northern flank. Thus the flood current is more affective to the sand bar. The sandy bottom sediment is mostly transported as bedload by the tidal currents. The magnitude asymmetry of the tidal currents results in a net sediment movement in one direction. The direction is onshore in the south and offshore in the north, which may result in a net counterlookwise rotation of the sands around the sand bar. However, the sand bar may migrate towards onshore due to the more affective flood current in the south. The irregular V-shaped outline of the sand bar in the south also seem to reflect the strong effect of flood current.

• Journal of Astronomy and Space Sciences
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• v.35 no.3
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• pp.151-161
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• 2018

Understanding solar influences on extreme weather is important. Insight into the causes of extreme weather events, including the solar-terrestrial connection, would allow better preparation for these events and help minimize the damage caused by disasters that threaten the human population. In this study, we examined category three, four, and five tropical cyclones that occurred in the western North Pacific Ocean from 1977 to 2016. We compared long-term trends in the positions of tropical cyclone occurrence and development with variations of the observed sunspot area, the solar North-South asymmetry, and the southern oscillation index (SOI). We found that tropical cyclones formed, had their maximum intensity, and terminated more northward in latitude and more westward in longitude over the period analyzed; they also became stronger during that period. It was found that tropical cyclones cannot be correlated or anti-correlated with the solar cycle. No evidence showing that properties (including positions of occurrence/development and other characteristics) of tropical cyclones are modulated by solar activity was found, at least not in terms of a spectral analysis using the wavelet transform method.

• Journal of Korea Water Resources Association
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• v.44 no.4
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• pp.315-325
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• 2011

There are not many practical measures to solve a water conflict, when a hydromorphologically asymmetric situation in international rivers exists whereby downstream users may not affect upstream users but upstream users do cause downstream impacts. In taking advantage of this merit, North Korea has built Imnam Dam in upstream of North Han River and uses water for trans-basin hydropower generation. As an impact of this dam South Korean' area as a downstream user has been suffered from water deficit and dry river. It is very critical for South Korea to solve a key problem such as water allocation for water supply and river maintenance. Therefore, this study is aim to suggest alternatives for equitable water allocation in consideration of special circumstances between the South and the North. For this, reviewing the allocation methods of water rights is carried using lessons obtained from international river cases. The results show that the minimum desired streamflow is calculated at 7.3 $m^3/sec$; water budget analysis by the equitable distribution of streamflows at the border line of the North Han River, the difference in water supply deficiency is at 3.7 $m^3/sec$ before and after Imnam Dam; in the determined distribution method, the difference in water deficiency is at 11.38 $m^3/sec$. These results show that South Korea should be secured 11.38 $m^3/sec$ from North Korean's Imnam Dam in respective of water use right and sound river maintenance.

• Journal of The Korean Astronomical Society
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• v.34 no.3
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• pp.157-166
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• 2001

The molecular cloud associated with the H II region S301 has been mapped in the J = 1-0 transitions of $^{12}CO$ and $^{13}CO$ using the 13.7 m radio telescope of Taeduk Radio Astronomy Observatory. The cloud is elongated along the north-south direction with two strong emission components facing the H II region. Its total mass is $8.7 {\times} 10^3 M{\bigodot}$. We find a velocity gradient of the molecular gas near the interface with the optical H II region, which may be a signature of interaction between the molecular cloud and the H II region. Spectra of CO, CS, and HCO+ exhibit line splitting even in the densest part of the cloud and suggests the clumpy structure. The radio continuum maps show that the ionzed gas is distributed with some asymmetry and the eastern part of the H II region is obscured by the molecular cloud. We propose that the S301 H II region is at the late stage of the champagne phase, but the second generation of stars has not yet been formed in the postshock layer.

• Strategy21
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• s.33
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• pp.113-147
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• 2014

While China's military rise is an issue of growing importance to regional security, it is worthwhile to note that it is not China's military modernization per se, but its capacity to project and sustain power along and beyond its borders--in particular, the possibility to resolve forcefully its outstanding maritime disputes and various contingencies. This essay argues that China's "anti-access capability"--a U.S.-coined term originally developed for a Taiwan contingency--is equally applicable to other major regional cases such as the Spratly disputes and a North Korean contingency. Furthermore, notwithstanding China's continuos efforts to develop and deploy various types and classes of weapons/platforms, it is the Russian systems and technologies that are most capable and thus likely assigned to the highest mission-critical areas. In assessing China's current and likely future military capability as well as their implications for the region, it is necessary to take note of the following: • There exists asymmetry of military capability between China and its weaker neighbors. While the PLAN is weak in several important aspects, for instance, many of its neighbors' navies are weaker still. • Some have argued that China's foreign policy behavior apparently became more "assertive" in 2009-2013, but it is wiser to keep in mind that China has almost always been assertive and aggressive when it comes to what China defines as "sovereignty and territorial issues" as well as its newest "core interests." • On the South China Sea disputes it is the function of U.S. presence in the theater--in the form of overseas bases and the freedom of navigation--and the PLA's own limitations to project and sustain power for an extended period of time that have largely prevented armed. • While Taiwan remains the idee fixe of China's diplomacy and military, it is and will be a tough nut to crack. China's recent creeping attempts for economic integration with Taiwan should be seen in this context. • China and Japan, the two regional heavyweights and traditional rivals, will likely have a bilateral relationship that is replete with difficulties and tension. China's unilateral announcement of its ADIZ in November 2013 as well as the occasional yet persistent disputes with Japan over the Senkaku/Diaoyudao/Diaoyutai islands are only the latest manifestation of this deeper and difficult relationship. • For Korean security it is imperative to take into account the geostrategic and historical factors. On top of the existing military threats from North Korea, the ROK should be able to employ a) hedging strategy, b) "limited defense sufficiency" strategy, and c) rock-solid relations with the United States.

• Journal of National Security and Military Science
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• s.8
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• pp.239-270
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• 2010

This thesis is to make an appropriate national defense policy of Republic of Korea through studying the Hegemony Strategy of United States. I searched the theory of hegemony. The hegemony was differently defined by the point of time and region. The strong power nations with the hegemony have been making efforts to maintain their hegemony everytime. I have conclusion that the presence of hegemony once emerged, it brought regional stability in place whether it is coercive or beneficial. The stability and instability of international order IS not exclusively dependent on hegemony. Even if the safety of hegemony cannot guarantee absolute stability of international order, there IS on doubt that the hegemony has enormous impact on that. According to the hegemonic theory, the history of mankind equals to the history of rising and falling hegemony. The international order was changed as the hegemony changes. The United States has been making efforts to maintain her global hegemony during the post cold-war era as well. Taking all these into consideration, relevant military strategy direction able to pursue national interest is that to make up for the relative weakness in the strategic environment. South Korea have to prepare security policy response as following. First, South Korea should build the military force equipped with advanced weapons in military technology sector and solidify military diplomatic relation able to form cooperative relation in wartime. Second, South Korea should make solid Alliance of Korea and U.S. Third, develop and maintain multilateral security cooperation of East Asia. Forth, we could realize that there are means that can neutralize opponent's strong point by seeking one or two and more asymmetry in the aspect of strategy, tactics, and means through asymmetric strategy. Than the military force of South Korea should develop into a force that is able to overcome to the traditional North Korea's threat and new type of conflicts. And the force should have sufficient strength and be deployed to effectively defend the Korean Peninsula. So, we need to establish a denial and defense system against any hostile neighboring country. Therefore, ROK military forces preparing for the future should try to construct a future military power to gradually establish enough strength for self-defense to prepare for a uncertain security environment and when the Korean Peninsula is unified in a future.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.4
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• pp.65-75
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• 2018

This thesis attempts to investigate and analyse the architectural characteristics of catholic churches in Gangwon province built in the 1950s. Catholic churches built at that time in Korea had many similarities basically since they were supported by UN forces after the Korean War and were established by priests connected to the Missionary Society of St. Columban. The results of study are as follows. In location, Except one catholic church, the catholic churches preferred low and gentle hill. In layout axis, catholic churches at Youngseo area preferred the north-south layout axis, whereas those at Youngdong favor the east-west layout axis. In approach, most of catholic churches around the Youngseo and Youngdong areas preferred entering the front entrance with a bell tower, whereas three of them at Youngdong did entering the front entrance with a bell tower around the rear corner. In floor plan, catholic churches at Youngseo preferred symmetry, whereas those at Youngdong preferred asymmetry. And every floor plan of catholic churches is rectangular type with transepts except one semicircular type. In apse shape, catholic churches in the Youngseo area preferred non-extruded types like a straight wall, whereas those in Youngdong have extruded types. Every catholic churches have no crypt under ground except one at Gangreung. Except one at Sokcho, every catholic church in this study has choir space in half story.