• Journal of the Korean Society of Safety
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• v.15 no.3
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• pp.102-107
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• 2000

The extensive use of pretensioned prestressed concrete in the modem construction industry, together with wider application of pretensioned components for structural purposes requires some important consideration on the adequate transfer of prestress force into the concrete, especially around the end zones of pretensioned member. The main objective of this paper is to study the effects of various important parameters on the bond characteristics of prestressing strand around the end zone of high strength pretensioned concrete members. To this end, a comprehensive experimental program has been set up. The principal test variables considered were strand diameter, concrete strength, concrete cover size. The present study provides valuable test data for the realistic and accurate determination of transfer length, which can be efficiently used for improving the design equation of transfer length in pretensioned prestressed concrete members.

• Korean Business Review
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• v.17
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• pp.153-183
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• 2004

The Gaisong Merchants can be regarded to playa pioneering role to activate the Korea's trade with foreign countries. In the early period of Yi-Dynasty, the Gaisong Merchants focused on personal trade, but in the middle period of Yi-Dynasty, they entered to the realm of governmental trade. Furthermore, their business activities widened to various forms of trades, for example, smuggling. Utilizing accumulated capital, Gaisong merchants expanded their trading activities to their neighboring countries such as Japan and China. In recent times, it is necessary for modem Korean companies to diversify risks through the establishment of corporations for production, marketing and R&D abroad or through joint venture, M&A and strategic alliance with foreign companies in order to reduce the risks originated from volatile economic and political situations. In this study, we utilize tools of comparative study to compare Gaisong Merchants' foreign trade strategies with those of modem companies such as AMOREPACIFIC, HANILCEMENT and SHINDORICO. The purpose of the paper is to test the hypothesis that modem Korean companies grew up by following the cases of Gaisong Merchants' business activities. We summarize our main findings as follows. First, both Gaisong Merchants and modem Korean companies have common functional core capability in the field of marketing, manufacturing technology, R&D, and human resources development. Second, both Gaisong Merchants and modem Korean companies have common organizational core capability. Third, both Gaisong Merchants and modem Korean companies have common infrastructures such as planning, finance, accounting and MIS. It constitutes the infrastructure of Korea's foreign trade sector. Fourth, both Gaisong Merchants and modem companies have common organizational culture in the field of management policy and philosophy. Actually, those factors are evaluated to be driving forces of Koera's success in foreign trade. In conclusion, the business activities of Gaisong Merchants who represented the peculiarity of Korean business spirit are partially inherited to current Korean business management. The value system and behavior pattern of modern Korean companies is succeeded from the spirit of Gaisong Merchants and it playa major role to specify the identity of Korean business administration.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11C
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• pp.1085-1097
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• 2009

We present a structure and design method of the D8PSK modem compatible with the VDL mode-2 standard and performance test results of the developed modem. In VDL mode-2, the raised cosine filter is used only in the transmitter and a general low pass filter is used in the receiver. Consequently, we can not achieve ISI reduction but can have better spectrum characteristics. Although there is 1~2 dB performance degradation with an un-matched filter compared to that with a matched filter, it is more important to minimize adjacent channel interference in narrow band communications. The transmit signal is generated digitally to avoid the problems(I/Q imbalance and DC offset etc.) of analog modulators. In addition the digital down converter using digital IF sampling technique is adopted for the receiver. This paper contains the overall configuration, design method and simulation results based in part on the previously proposed structures and algorithms. It is confirmed that the modem transmits and receives messages successfully at a speed of max. 870 km/h over ranges of up to 310 km through the ground and in-flight communication tests.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.1
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• pp.175-181
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• 2015

In this paper, we develop a 2.4GHz ISM band wireless communication platform prototype based on embedded linux which support can be u-Hospital service. The developed system is available connecting between ARM920T processor board and FPGA board and linking IEEE 802.11b PHY board, AD/DA(10Bit) and RF(2.4GHz) board for wireless access. It is also can be utilized for the embedded system design with IEEE 802.11b/g Access Point(Option: IEEE 802.11a/b/g) test due to the Embedded Linux. Also, the developed system is possible to test and verify the radio access technology, Modem(OFDM etc) and IP(Intellectual Property) circuit. And make the most use of the system, we search for a expansion to that home and mobile healthcare, wellness service application.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.7
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• pp.46-56
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• 2002

In this paper, we describe a hardware-software co-verification methodology and environment in developing a mobile station modem chip for cdma2000 1x which is one of the 3rd generation mobile communication standards. By constructing an efficient co-verification environment for a register-transfer-level hardware model and a physical-layer software model combining a channel link simulator and a versatile test-bench, we can drastically reduce both time and cost for developing a complex three-million-gate class system integrated circuit.

• Journal of Family Resource Management and Policy Review
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• v.15 no.3
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• pp.1-22
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• 2011

The purpose of this study is to offer basic data on family rite education, as well as to suggest future directions for family rites by surveying differences in the understanding and the practice of family rites among female undergraduates, who will be the future leaders of our society. General proclivity toward, and differences between understanding and practice of family rites, as well as the effect of socio-demographic variables on these differences, were further verified with a one-way ANOVA, a t-test, and a Duncan's Multiple Range Test. This study had two main findings. First, the gap between understanding and practice in family rites, ordered from largest to smallest by sub-sphere, was found to be: coming-of-age ceremonies, birthday rituals, ancestral rituals, funeral rites, and wedding ceremonies. Second, as for the results of the analysis of the difference between understanding and practice of family rites in female undergraduates according to socio-demographic variables, among a total of 18 variables, significant differences were found in: own religion, brother's rank, mother's religion, father's religion, mother's job, place where the individual grew up, having experienced family rites, education. place of residence, and monthly income. In the face of a changing era and environment, the basic spirit of family rites has not changed. However, a new harmony between tradition and modem times is needed. This can be achieved through the establishment of a suitable form of rites for the present age, while taking on a modem acceptance of the significance traditionally associated with these rites.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.349-353
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• 2001

An air foil bearing is developed for the high speed generator. The bearing is type of multi-leaf and is stable on 60,000RPM. The vibration level is 12um(p-p) and the highest temperature level is below 100$^{\circ}C$. The dynamic parameter of air foil bearing is acquired by experimental method using exciter. The air foil bearing is also good condition at test of real generator and load condition. The condition of foil is very good after 3,000cycle start-stop test. Therefore the air foil bearing is ideal for high speed, light weight and modem turbo-machinery.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1947-1948
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• 2008

This paper presents the implementation of Power Line Communication(PLC) module which can reduce standby-power consumption. The suggested PLC module consists of PLC modem, coupling circuit, ZCP(Zero-Cross Point) Circuit and main SMPS control relay. The test results under power line communication test-bed used home appliance show the 77% saving of standby-power.

• International Journal of Aeronautical and Space Sciences
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• v.5 no.1
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• pp.6-18
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• 2004

This paper addresses the development and design of the HAUSAT-l (Hankuk Aviation University SA'Tellite-D communication subsystem, which is a next generation picosatellite, developed by SSRL (Space System Research Lab.) of Hankuk Aviation University. The communication subsystem generally consumes the majority of power and volume for picosatellites, and thus its design is critical to the overall satellite and mission plans. The HAUSAT-l designs are implemented by using the 145.84 MHz for uplink and 435.84 MHz for downlink frequency bands. The simulation and test results of the homemade radio and the TNC (Terminal Node Controller) integrated on the HAUSAT - I , a picosatellite scheduled to launch on September 2004 by Russian launch vehicle "Dnepr", are presented for EM, QM and FM, respectively.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.348-350
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• 2003

In recent years, with the continuous development of modem power system, the need for high performance protection to meet the customers' requests for more stable and reliable power supply has become increasingly emphasized. So, there is urgent need for a proper testing platform about not only existing digital protection relay but also new digital protection relay on the transmission line. It is also dynamic-state test which can test the performance of digital relay. This paper suggests basic system model for testing transmission line protection using PSCAD/EMTDC, and presents the process of the component modeling in the basic system.