• The Journal of Korea Robotics Society
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• v.6 no.4
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• pp.334-343
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• 2011

This paper presents a new approach for mobile robot heading detection using MEMS Gyro north finding method in the indoor environment. Based on this, the robot heading angle measurement scheme is proposed; improved north finding theory and algorithm are also explained. Several approaches are applied to confirm system's precision and effectiveness. In order to find out the heading angle, a single axis MEMS gyroscope to sense the angle between the robot heading direction and the north is used. To reach enough estimation accuracy and reduce detection time, the least square method (LSM) for the signal fitting and parameter estimation is applied. Through a turn-table, we setup a carouseling system to decrease the substantial bias effect on gyroscope's heading angle. For the evaluation of the proposed method, this system is implemented to the Pioneer robot platform. The performance and heading error are analyzed after the test. From the simulation and experimental results, system's accuracy, usefulness and adaptability are shown.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.291-294
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• 2004

There are many position fixing systems in the world from ancient times. But the principles are to compare the position to want to know with the known position already. The position finding system which is not restricted by weather condition and/or electronic apparatus has been sought. The best system is the GPS as far. But the system has the fatal faults as follows; 1. to depend on satellite's accuracy, 2. not to use underwater. This paper is to investigate theoretically position fixing and north finding by using free gyroscope. This paper introduce a position fixing and north finding method by measuring inclination of 2 free gyroscopes. And this system does not depend on the weather condition and underwater condition. What is more, it could use on the planets, if the gravity exits.

• KDI Journal of Economic Policy
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• v.42 no.4
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• pp.1-25
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• 2020

The international community's sanctions against North Korea, triggered by North Korea's nuclear tests and by missile development in the country, are considered the strongest sanctions in history, banning exports of North Korea's major items and limiting imports of machinery and oil products. Accordingly, North Korea's trade volume decreased to the level of collapse after the sanctions, meaning that the sanctions against North Korea were considered to be effective. However, according to this paper, which analyzed the price fluctuations of refined petroleum products in North Korea through the methodology of an event study, the market prices of oil products were only temporarily affected by the sanctions and remained stable over the long run despite the restrictions on the volumes of refined petroleum products introduced. This can be explained by evidence that North Korea has introduced refined oil supplies that are not much different from those before the sanctions through its use of illegal transshipments even after the sanctions. With regard to strategic materials such as refined oil, the North Korean authorities are believed to be desperately avoiding sanctions by, for instance, finding loopholes in the sanctions to meet the minimum level of demand.

• Journal of Power System Engineering
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• v.19 no.3
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• pp.36-41
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• 2015

The true north-finding equipment utilizing gyro sensor is used for INS(Inertial Navigation System) and has an increasing preference for gyro compass system due to compact size, lightening, low power and price. The purpose of this experiment is to research gyro compass system providing high performance in the field of manned or unmanned gyro compass system which proposes the accuracy of 1% utilizing experimented equipment at true north of the earth. Unlike the conventional system, the proposed gyro sensor system indicates to be applied in the various and specific equipment using multiple technique and method.

• Phonetics and Speech Sciences
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• v.10 no.1
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• pp.1-7
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• 2018

Categorical production in language processing helps speakers to produce phonemic contrasts. This categorization and production is utilized for the production-based and imitation-based approach in the present study. Contrastive signals in speakers' speech reflect the shapes of boundaries with categorical characteristics. Signals that provide information about lexical pitch accent contrasts can introduce categorical distinctions for productive and cognitive selection. This experiment was conducted with nine North Kyungsang speakers for a production task and nine North Kyungsang speakers for an imitation task. The first finding of the present study is the rigidity of categorical production, which controls the boundaries of lexical pitch accent contrasts. The categorization of North Kyungsang speakers' production allows them to classify minimal pitch accent contrasts. The categorical production in imitation appeared in two clusters, representing two meaningful contrasts. The second finding of the present study is that there are individual differences in speakers' production and imitation responses. The distinctive performances of individual speakers showed a variety of curves. For the HL-LH patterns, the categorical production tended to be highly distinctive as compared to the other pitch accent patterns (HH-HL and HH-LH), showing that there are more continuous curves than categorical curves. Finally, the present study shows that, for North Kyungsang speakers, imitative production is the core type of categorical production for determining the existence of the lexical pitch accent system. However, several questions remain for defining that categorical production, which leads to ideas for future research.

• Journal of Korean Academy of Nursing
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• v.43 no.3
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• pp.431-441
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• 2013

Purpose: The study was done to explore meanings and essence of the experience in South Korea of men defectors from North Korea. Methods: Data were collected from March, 2011 to May, 2012, through in-depth interviews with ten men defectors. Data analysis was conducted using the process of hermeneutic phenomenological reflection. Results: Eight essential themes were extracted; 'buoyant expectation for a new life', 'feeling guilty about family left behind in North Korea', 'inability to become acclimatized due to communication difficulties', 'inability to socialize with South Koreans due to different lifestyles', 'finding strength through trustworthy acquaintances', 'continuing reconciliation with oneself while trying to assimilate into South Korean culture', 'self-realization of one's original self', and 'continuing to feel out the possibility of a future in South Korea'. Conclusion: The findings indicate that North Korean men who defect to South Korea shape their identity through three phases: forming self-image during escape from North Korea, trying to become accustomed to South Korean society, and finding their own identity by self-realization of their original self. Eventually, the whole process enables them to recover their identity, to feel a sense of belonging, and to discover possibilities for a better future.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1356-1363
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• 2005

In the gyrocompass system, the use of the fiber optic gyroscope(FOG) makes this traditional system considerably attractive because it has strong points in terms of weight, power, warming-up time, and cost. In this paper, a novel digital north-finding method based upon an FOG, which can be applied to the gyrocompass system, is proposed. The analytical model for the earth signal of the FOG is described, and the earth signals passed through lock-in amplifiers are modeled. Additionally, a north-finding algorithm using two lock-in amplifier outputs is developed, and the proposed method is organized by the developed algorithm. Simulation results are included to verify the performance of the proposed method.

• Journal of Arbitration Studies
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• v.17 no.1
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• pp.157-181
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• 2007

The commercial relationship between South and North Korea is defined under the concept of economic relation and cooperation. To resolve any dispute that can arise from the trade and investment relations between South and North Korea, 'Agreement on the Procedures to Resolve Commercial Arbitration of South-North Korea' came into force in August 2003. Commercial Arbitration Committee of South-North Korea will be organized as the member lists of the committee were exchanged in July 2006 between South and North Korea. This committee must become a central system to settle the trade and investment disputes between South and North Korea. North Korea's Foreign Economic Arbitration Act was enacted to provide the foreign investors with the safe measures in their investments such as dispute resolution. But this Act can not dispute the trade and investment disputes between South and North Korea. The purpose of this paper is to contribute to the activation of arbitration between South and North Korea by studying Commercial Arbitration Committee of South-North Korea introduced by Agreement on the Procedures to Resolve Commercial Arbitration of South-North Korea and Agreement on the Construction and Operation of Commercial Arbitration Committee of South-North Korea and finding the problems and solutions of Commercial Arbitration Committee of South-North Korea.

• Korean Journal of Veterinary Service
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• v.31 no.3
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• pp.315-329
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• 2008

A total of 710 bovine serum samples which are composed 532 bovine serum samples showed negative reaction and 178 bovine serum samples showed positive reaction with tube agglutination test (TAT) from North area of Gyeong-nam, Korea were tested using all the 3 assays which are Rose-Bengal test(RBT), tube agglutination test (TAT) and enzyme-linked immunosorbent assay (ELISA, two types) and analyzed for evaluation of specificity, sensitivity, reproducibility and predictive value. In the comparison of serum antibody titer agglutination test, RBT showed almost agreement with TAT. In the comparison of TAT and two types of ELISA method, they showed difference in specificity and sensitivity about 5%. But there is no significant difference in detecting sensitivity between two types of ELISA method and TAT. In serologic tests for bovine brucellosis, the new assay ELISA would be a good candidate for serologic survey for bovine brucellosis in Korea because it is efficient in detecting many test samples quickly. But the serum agglutination tests (RBT, TAT) are more economical and easy assay for detection. In the test of comparison of antibody titer between first day of finding and 10 days after finding by TAT, there was no change in 55% (76/139) of positive cattle.

• Journal of the military operations research society of Korea
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• v.15 no.2
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• pp.79-93
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• 1989

This research paper is aimed at developing an optimal strategy for finding espionage ship sent from North Korea. The optimal strategy developed here handles detection rate and probability that the espionage ship is in a certain specific sea area. A detection model is developed and an application problem is illustrated.