• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.1
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• pp.36-45
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• 2017

Abstract It is necessary to verify the properties of an inertial measurement unit in the flight environment before applying to military applications. In this paper, we presented a new approach to verify an inertial measurement unit(IMU) in regard to the performance and the robustness in flight environments for the high-dynamics vehicle systems. We proposed two methods for verification of an IMU. We confirmed normal operation of an IMU and properties in flight environment by using direct comparison method. And we proposed real time multi-navigation system to complement the first method. The proposed method made it possible to compare navigation result at the same time. Therefore, it is easy to analyze the performance of an inertial navigation system and robustness during the vehicle flight. To verify the proposed method, we carried out a flight test as well as an experimental test of flight vibration on the ground. As a result of the experiment, we confirmed flight environment properties of an IMU. Therefore, we shows that the proposed method can serve the reliability improvement of IMU.

• Journal of the Korean association of regional geographers
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• v.9 no.4
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• pp.505-518
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• 2003

The purpose of this paper is to review Post-Fordist urban economic theories that have tackled the recent changes of urban economies in large cities in the world since 1980s, so that we can conceptualise the changes of urban economies in Korean cities. In the perspective of the Post-Fordist urban economic theories, the recent changes of urban economies in the world are deeply related to the transformation of capitalist world economic system from Fordism to Post-Fordism. To see these changes which can be called as the new urbanization process in the economic aspect, we will focus especially such theories as new industrial space (district) theory based on the flexible specialization paradigm, informational city theory based on the information and communication mode paradigm, and cluster and regional innovation theory based on the institution and network paradigm. Also we will consider the social polarization process and dual city phenomena that have been observed for the most part of big cities in the world.

• Journal of Astronomy and Space Sciences
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• v.11 no.1
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• pp.71-80
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• 1994

It is generally known that the measurement of the ionospheric total electron content(TEC) by GPS can more accurately monitor the broader area of the ionosphere than other current methods. \Ve measured the TEC along a slant path considering the arrival time differences of P-code which is transmitted from GPS satellites with the modulation on two L-band carrier frequencies, L1 (1574.42MHz) and L2 (1227.60MHz). Under the assumptions that the ionosphere is uniformly distributed and its average height is 350km, we transformed the slant TEC to the vertical TEC at the point that the line-of-sight direction to GPS satellite cut across the average height of the ionosphere. Because there is no dual frequency P-code GPS receiver in Korea, we used the data observed at the TAIW GPS station ($N25^{\circ},E121.5^{\circ}$) in Taiwan which is one of the core stations in International GPS and Geodynamics Services (IGS). The TEC values obtained in this work showed a typical daily variation of the ionosphere which is high in the daytime and low in the nighttime. Our results are found to be consistent with the SOLAR-DAILY data of NOAA and the Klobuchar's model for the ionospheric correction of GPS. In addition, in the cornparision with SOLAR-DAILY data, we estimated the precision of our TEC measurement as 2 TEC.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.68.1-68.1
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• 2014

We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual channel imaging spectrograph (S-channel 900-1150 ${\AA}$, L-channel 1350-1710 ${\AA}$, and ${\lambda}/{\Delta}{\lambda}$ ~ 550 for both channels) with large image fields of view (S-channel $4.0^{\circ}{\times}4.6^{\prime}$, L-channel $7.5^{\circ}{\times}4.3^{\prime}$, and angular resolution ~ $5-10^{\prime}$) optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) were made in two campaigns during its perihelion approach between May 8 and 15, 2004. Based on the scanning mode observations in the wavelength band of 1400-1700 ${\AA}$, we have constructed an image of the comet with an angular size of $5^{\circ}{\times}5^{\circ}$, which corresponds to the central coma region. Several important fluorescence emission lines were detected including S I multiplets at 1429 and 1479 ${\AA}$, C I multiplets at 1561 and 1657 ${\AA}$, and the CO $A^1{\Pi}-X^1{\Sigma}^+$ Fourth Positive system; we have estimated the production rates of the corresponding species from the fluxes of these emission lines. The estimated production rate of CO was $Q_{CO}=(2.65{\pm}0.63){\times}10^{28}s^{-1}$, which is 6.2-7.4% of the water production rate and is consistent with earlier predictions. The average carbon production rate was estimated to be $Q_C={\sim}1.59{\times}10^{28}s^{-1}$, which is ~60% of the CO production rate. However, the observed carbon profile was steeper than that predicted using the two-component Haser model in the inner coma region, while it was consistent with the model in the outer region. The average sulfur production rate was $Q_S=(4.03{\pm}1.03){\times}10^{27}s^{-1}$, which corresponds to ~1% of the water production rate.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.12
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• pp.1032-1039
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• 2012

The present paper deals with precise relative positioning of formation satellites with long baseline in low Earth orbit making use of L1/L2 dual frequency GPS carrier phase measurements. Kinematic approach means to describe the motion of objects without taking its mass/dynamics model into consideration. The advantage of the kinematic approach is that information about dynamics of the system is not applied, which gives more flexibility and could improve the scientific interest of the observations made by the mission. The ionosphere terms, which are not canceled by double differenced measurement equation in the case of the long baseline, are explicitly estimated as unknown parameters by extended Kalman filter. The estimated float ambiguities by EKF are solved by existing efficient integer vector search strategy under integer least square condition. For the integer vector search, we employ well known MLAMBDA. Finally, The feasibility and accuracy of processing scheme are demonstrated using the GPS measurements for two satellites in low Earth orbit separated by baselines of 100 km.

• Journal of KIISE:Software and Applications
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• v.32 no.11
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• pp.1021-1028
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• 2005

The general solution for classification and regression problems can be found by matching and modifying matrices with the information in real world and then these matrices are teaming in neural networks. This paper treats primary space as a real world, and dual space that Primary space matches matrices using kernel. In practical study, there are two kinds of problems, complete system which can get an answer using inverse matrix and ill-posed system or singular system which cannot get an answer directly from inverse of the given matrix. Further more the problems are often given by the latter condition; therefore, it is necessary to find regularization parameter to change ill-posed or singular problems into complete system. This paper compares each performance under both classification and regression problems among GCV, L-Curve, which are well known for getting regularization parameter, and kernel methods. Both GCV and L-Curve have excellent performance to get regularization parameters, and the performances are similar although they show little bit different results from the different condition of problems. However, these methods are two-step solution because both have to calculate the regularization parameters to solve given problems, and then those problems can be applied to other solving methods. Compared with UV and L-Curve, kernel methods are one-step solution which is simultaneously teaming a regularization parameter within the teaming process of pattern weights. This paper also suggests dynamic momentum which is leaning under the limited proportional condition between learning epoch and the performance of given problems to increase performance and precision for regularization. Finally, this paper shows the results that suggested solution can get better or equivalent results compared with GCV and L-Curve through the experiments using Iris data which are used to consider standard data in classification, Gaussian data which are typical data for singular system, and Shaw data which is an one-dimension image restoration problems.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.124-136
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• 2011

In landscape architecture, plants play an important role in realizing the intention of the architect and user- behavior as well as an ecology and appearance of the space for them. However, it is true that many researches have focused on ecological characteristics of plants, their cultivation environment and symbolic meanings in traditional terms, while relatively few for the analysis of the aspects of each period through plants. For this, cherry trees that we often see around are selected and their introduction, propagation, development and symbolism from the view of chronicle are studied and the results are followings; Firstly, three-year seedlings of 1,500 pieces of cherry tree from Osaka and Tokyo were planted for the first time in Oieseongdae, Namsan Park, Seoul. Since then, they had been widely planted at traditional sites, modern parks, newly-constructed roads for street trees, and for this, the Japanese Government-General of Chosun had actively supported by its direct cultivation and selling of cherry trees. The spread of cherry trees planted raised the question of whether or not Prunus yedoensis is originated from Jeju Island. Secondly, such massive and artificial planting of them had become attractions over the time and mass media at that time also had actively promoted it. And such trend made the day and night picnic under the cherry blossoms one of the most representative cultures of enjoying spring in Seoul. Thirdly, although general people enjoyed cherry blossoms, but they had dual view and attitude for cherry trees, which were well expressed in their use of them: for example, cherry blossoms, aeng and sakura were used altogether for same meaning, but night aeng or night picnic under cherry blossoms were especially used instead of yojakura when mentioning just pleasure, which meant some saw night enjoying cherry blossoms a low culture. Fourth, symbolic space of Chosun had been transformed into the space for enjoyment and consumption. Anyone who paid entrance fee could enjoy performance of revugirl, cinema and entertainment along with enjoying cherry blossoms. The still-existing strict differentiation of enjoyment culture by social status, class and ethnicity was dismantled from that trend and brought about a kind of disorder. From this, we could find that cherry blossoms had made a great contribution to the change of traditional enjoyment culture over the Japanese colonial period and become a popular spring enjoyment.

• Archives of design research
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• v.11 no.2
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• pp.31-45
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• 1998

Human beings receive experiences and education in viewing and manipulating objects since birth, These experiences in forms and colours influence signifrcantty the formation of the person's humanity, sensibility and constituOOn until he becomes an adult. Considering that all objects coexist through space and time with human beings from birth to an adulthood, we can imagine how these things shape a person, Human beings' perception of form and colour might be different according to the person's living environment, experiences, education, age and job, However, when we see there are certain kinds of form and colour of that most people favor, we can understand that human beings have a certain inherent feelings about forms and colours, Let's suppose a man faces an object that dosen't correspond with his basic feelings about form and colour, He would avoid that object at least unconsoousty, All of his acts dealing with form and colour probably satisfy a desire for beauty which can be required from certain proper forms and colours, By revealing the feelings about forms and colours that human beings originally have, this study is going to explore what kinds of form and colour have what kinds of psychological and physical influences on human beings. Another purpose of this study is to be a theory suggesting more profitable and effective forms and colours psychologically and physically to the consumer. this study demonstrates that the basic feelings about forms and colours which human beings possess are different according to the individual's psychology and the body's condition. It also establishes the reality of the principle of how human psychology and the body change according to the surrounding environment. Finally, it will be appropriate for the suggested theory from this study to be used as fundamental material in deciding the forms and colours used in the design field in the future in that these forms and colours are more profitable and efftient.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.3
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• pp.98-106
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• 2011

This study was performed with the purpose of providing basic data for the improvement of zoning regulations of urban nature park by analyzing the present problem which occurred during last 6 years from the year of 2005 when the program was introduced for the first time. The study was processed first by the analysis of the cases of problems evoked by citizens, second the other problems was delineated by interviews of officials, at last the validity of all of the problems was verified by a group of professionals through delphi method. The results can be summarized as follows. 1. In relation to the designation and management of urban national park areas, designation criteria, designation process, maintenance, laws and regulations and 20 other items were found to be problematic. After Delphi method, 5 items were removed and 2 added. The results showed that there were 17 problematic items in total. 2. Regarding the problem of criteria for designation, which are, lack of priority(weights), lack of objectivity due to the difficulty to use quantitative evaluation method, incompatibility for contaminated land environmental impact assessment, incompatibility of land suitability assessment, lack of detailed field survey standards, lack of national park area standards, and 6 other items. 3. Regarding the problem of designation process, which are, the occurrence of civil appeals for designating a new national park, the needs of feasibility study on the urban national park areas constructed before urban national park guidelines came out, lack of a comprehensive review of the boundaries set when determining national park area management plan, poor temporal and financial conditions for an accurate field survey, and 4 other items. 4. Regarding the problem of maintenance management, which are, lack of management system in each space, lack of effectiveness of Urban Nature Park Area Management Plan among master plans for park and green areas, the occurrence of dual managers due to dual natures such as purpose area and city park, lack of professional manpower to manage park areas, and 4 other items. 5. Regarding the problems of regulation guidelines, which are, lack of separate urban park area management plan, incompatibility of the permitted facilities in the park to the park area standards, lack of feasibility study on urban park areas, and 3 other items.

• The Korean Journal of Archival Studies
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• no.39
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• pp.281-318
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• 2014

This article aims to inquire into the decision making system and the sources of the original documents made by means of it in Imperial Japan, the colonial Chosun, GHQ, and the occupied Japan in terms of the post-war treatments of compensation on the Japanese colonial rules. It deals with them from 1910 to 1952 in the perspective of history and archivistics. This article attempts to establish the foundation on which the perception of the documents made in the Imperial Japan, its colony, and the occupied territory would be widened by placing the colonial rules and the compensation on them into a continuous line. The records of Japan's forced occupation of Korea during 1910-1945, and the original records documenting the decision making process of post-war compensation under GHQ, 1945-1952, have been dispersed in Korea, Japan and the United States. This dispersed preservation was mainly due to the complicated decision-making process among Governor-General of Chosun, the Japanese Imperial government, and the GHQ. It was the top-down styled, dual decision making system, in which the critical policies, personnel, and budget had been decided in Imperial homeland, while their implementations were made in the colonies. As a result, the records documenting the whole process of domination have been preserved dispersedly in Japan and its colonies. In particular, the accounts of not yet paid Korean workers that was forced to mobilize in Japan's colonial periods, which is emerging as the diplomatic conflict between Korea and Japan, had been dealt in the decrees of the Japanese government and policy-making of GHQ. It has already been changed to the problem as 'economic cooperation' from the 'debt'. Also, the critical records for post-war compensation were preserved dispersedly in the United States and Japan under the top-down decision making process of GHQ-Japan. Therefore, the dispersed records of 1910-1952 about the colonial rules by the Imperial Japan and the post-war compensation on them must be re-investigated for the adequate documentation in the context of time and space.