• Korean Journal of Optics and Photonics
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• v.23 no.5
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• pp.203-210
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• 2012

Sagnac interferometer gyroscopes can be divided into three large generations using starting points of time or highlights of their research. As the first generational Sagnac interferometer, the ring laser gyroscopes have been studied since the 1960s by laser invention, and as the second generational Sagnac interferometer, the fiber optic gyroscopes have been studied since the 1970s by invention of optical fiber for communication. In the latter half of the 1990s, after having confirmed the wave theory of the atom, studies of atomic interferometers were started for a next generation gyroscope application. This paper discusses the operation principles, application, and future prospects of these three generations of Sagnac gyroscopes.

• Ocean and Polar Research
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• v.26 no.3
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• pp.523-529
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• 2004

The seismic monitoring at Syowa Station$(69^{\circ}S,\;39^{\circ}E: SYO)$, located on the continental margin of the Eastern Dronning Maud Land, East Antarctica, began in 1959. Phase readings of the earthquakes have been reported since 1967 and have been annually published as part of the Data Report Series of the National Institute of Polar Research since 1968. An observation of a tripartite seismic network was carried out at SYO for a period of three years from 1987 to 1990. Epicenters of local earthquakes were determined for the first time by using the array network for the three-year period. Many different types of earthquakes, such as the mainshock-aftershock type, twin earthquake, earthquake swarms, etc., were detected during the period. After this, local events around SYO have been detected empirically from their waveforms recorded on seismograms. The seismic activity for the period of 1987-1990 was higher than that of the following decade. Earthquake epicenters, occurring during that period, were highly localized along the coast and in the central part of the $L\"{u}tzow-Holm$ Bay (LHB). Nine local earthquakes, recorded during the period of 1990-1996, showed many different types of events. The seismicity for the period of 1990-1996 was very low and the magnitudes ranged from 0.1 to 1.4. The locations of some events were determined by using the single station method for SYO, i.e., using the particle motions of the initial phase and S-P time. Two local events were detected in 1998 and one event in 2001. It would be estimated that the stress concentration was related to the glacial rebound around the LHB. Afterwards, we will be able to eventually examine the relationship between the seismicity around Antarctica and deglacial phenomena such as crustal uplift, and sea level change within the earth environmental system.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.449-452
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• 2008

Originally developed in Scandinavia over 40 years ago, syphonic roof drainage systems have been in use in the UK since the early 1990's. Since then, many large projects have used the syphonic system to overcome installation problems which would have been difficult to solve using a traditional gravity rainwater system.

• Land and Housing Review
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• v.2 no.3
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• pp.227-238
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• 2011

There are similarities between Korea and Japan in terms of national planning and development system and housing policies. Japan has suffered from great shifts of social and economic systems due to skyrocketing land prices for three times and the collapse of the bubble economy after the Second World War. The study reviews historically important changes in the national territory and housing policies for last 60 years in Japan. It also investigates changing trends and characteristics of many socioeconomic indicators with regard to population, housing and other fields in response to these policies. First of all, Japan has experienced significant economic growth before and after the 1960's, and the era of national rebuilding projects in the 1970's. After then, the period of the bubble economy has emerged since 1980; however, it suffered from skyrocketing land values between the late 1980's and the early 1990's, and the collapse of Japanese bubble economy in the early 1990's. In response, many urban regeneration policies and projects were proposed to recover the national economy since 2000. It is found that these national territory development and housing supply policies throughout the country have been influenced by the changing characteristics of social and economic conditions. Since the housing supply ratio in 1968 reached up to around 100% on average, Japan has been focusing attention to improving the residential and living quality for existing housing stock rather than supplying new housing units through large-scale new town projects. These experiences are full of helpful suggestions for our future housing and urban regeneration policies as we reach to more than 100% of housing supply ratio on average.

• Nuclear Engineering and Technology
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• v.44 no.6
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• pp.689-696
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• 2012

A small integral reactor SMART (System Integrated Modular Advanced ReacTor), being developed in Korea since late 1990s and targeted to obtaining a standard design approval by the end of 2011, is introduced. The design scope and level for design certification (DC) is well described in the U.S. NRC SECY documents published the early 1990s. However, the documents are valid for a one-step licensing process called a combined operating license (COL) by the U.S. NRC, while Korea still uses a two-step licensing process. Thus, referencing the concept of the SECY documents, we have established the design scope and level for the SMART DC using the contexts of the standard review plan (SRP). Some examples of the results and issues raised during our review are briefly presented in this paper. The same methodology will be applied to other types of reactor under development in Korea, such as future VHTR reactors.

• Journal of The Geomorphological Association of Korea
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• v.18 no.2
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• pp.15-23
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• 2011

The first paper on the floodplain in Korea was published in the late 1960s. In 1970s and 1980s the study on the floodplain and delta of Korea was led by Hyuck Jae Kwon(emeritus professor at Korea University) and Hwa-Ryong Jo(emeritus professor at Kyungpook National University). Kwon established the foundation of the study and Jo analyzed the alluvial landforms microscopically. Since 1990s, the study on the floodplain and delta has entered a phase of stagnation.

• Journal of the Korean Society of Costume
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• v.52 no.5
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• pp.155-172
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• 2002

The research has the aim of defining the special characteristics of the functionalist fashion design in the 1900s by understanding the essence of functionalism in the sociocultural contexts. Giving careful consideration to functionalist fashion design in the 1990s makes it possible to foresee the way of fashion design to meet the needs of the modems and men of the future world. To obtain the purposes, documentary study and demonstrative study with fashion photographs have been executed. Main results are as follows. Functionalism in the 1990s has been developed in different ways from the analogies in the beginning of the 20th century. It doesn't belong to an analogy but has the fused characteristics. It can be classified into techno functionalism influenced by new technology Pure functionalism related to minimalism. casual functionalism for those who are crazy about the speed and sports and enjoy the freedom and comfort and symbolic functionalism. Mechanical analogy has been developed into techno functionalism. Pure functionalism has come from the blend of mechanical and moral analogy, casual functionalism from mechanical. organic and moral analogy. and symbolic functionalism from organic and moral analogy. Since fashion design has much closer relation to human body and movements. it has been expressed considering a division of men and women and the places and times for the designs more than other designs. More casual manners of formal wear are distinct elements in functionalist fashion design in the 1990s. The 20th century general cultural phenomena including post modernism can be explained by eclectic functionalism. Functionalism considering Practical and conceptional functions ill continue and techno functionalism and casual functionalism in future fashion design will be expressed more strongly with new technology and casual trends of life style.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.1
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• pp.90-101
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• 2011

From 1990s, the lunar exploration programs, suspended over 20 years after the project Apollo's first successful human landing on the Moon in 1969, have been restarted according to a revived interest in Moon. In recent, several nations progress their own lunar exploration program successfully. In this report, to investigate the technical trends of the onboard propulsion system for the lunar orbiter, technical features related to the performance of the propulsion system of the lunar orbiters developed since 1990 are surveyed. In the future, it is expected that this technical report can provide a fundamental guideline for selecting a proper type of the onboard propulsion system for the domestic lunar orbiter.

• Current Industrial and Technological Trends in Aerospace
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• v.7 no.1
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• pp.56-67
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• 2009

From 1990s, the lunar exploration programs, suspended over 20 years after the project Apollo's first successful human landing on the Moon in 1969, have been restarted according to a revived interest in Moon. In recent, several nations progress their own lunar exploration program successfully. In this report, to investigate the technical trends of the onboard propulsion system for the lunar orbiter, technical features related to the performance of the propulsion system of the lunar orbiters developed since 1990 are surveyed. In the future, it is expected that this technical report can provide a fundamental guideline for selecting a proper type of the onboard propulsion system for the domestic lunar orbiter.

• Journal of the Korean Professional Engineers Association
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• v.34 no.3
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• pp.10-15
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• 2001

The biotechnology is the study of biochemical and biological processes in living things. Since 1990's biotechnology has developed more repidly than all of the life technical industries, through the use of extremly sensitive analytical instruments, computers, and radioactive tracers. The biotechnician has been able to gain an understanding of the mechanisms and information on biotechnology, enables the biologist and biochemist to fine farther information about DNA techniques and human beings.