• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1069-1075
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• 2004

In this paper, we show the equivalence between complementary code keying (CCK) codeword and coset of the first order Reed-Muller (RM) code with variables of three. The CCK codewords are Golay sequences which have peak-to-average power ratio (PAPR) of two at most and can correct one error. We propose a CCK-orthogonal frequency division multiplexing (OFDM) modem to reduce PAPR. Also, we present the performance improvement techniques by increasing the variables of four to correct three errors and reduce PAPR at least 9㏈ with this system. Although, two Fast Hadamard Transform (FHT) blocks of size 8 64 are required at the receiver, we reduce the complexity by using FHT blocks of size 8 64 and 2 4 without deteriorating the performance. We generalize our results that we may increase the variables of RM code to enhance the error correcting and PAPR reduction capabilities without increasing receiver's complexity.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.8
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• pp.1254-1260
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• 2009

CDMA tele-Controller system is designed with a low power consumption 8 bit microcontroller, ATmega 2560. ATmega 2560 microcontroller consists of 4 UART (Universal asynchronous receiver/transmitter) ports, 4 kbytes EEPROM, 256 kbytes flash memory, 4 kbytes SRAM. 4 URAT is used for CDMA modem, communication for GPS module, EEPROM is used for saving a configuration for program running, a flash memory of 256 kbytes is used for storing a F/W(Firm Ware), and SRAM is used for stack, storing memory of global variables while program running. We have tested the communication distance between the coast station and sea by the fabricated control board using 800 MHz CDMA modem and GPS module, which is building for the navigational aid management system by remote control. As a results, the receiving signal strength is above -80 dBm, and then the characteristics of the control board implemented more than 10 km in the distance of the communication.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.3 no.4
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• pp.255-260
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• 1991

A voltage measuring system specified for the voltage fluctuation of the Pusan-Hamada submarine cable is developed by adding circuits of differential amplification and analog-to-digital conversion to a microprocessor-based data logger with a data modem. This system is charaterized by its small size. no power failure. fully unmanned operation. and precise instrumental drift correction. In addition to the cable voltage and current it measures an ambient temperature and a mercury cell voltage in order to calibrate temperature effect and check its long-term stability. The data acquired by this system show that the voltage signal. comprising fast random noises with a constant width of about 0.2V. fluctuates within a range of about 1V and the fluctuation frequency is similar to that of tidal motion. The source voltage of power feeding equipment (PFE) for the cable system seems to be affected when the room temperature changes rapidly.

• Journal of Advanced Navigation Technology
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• v.14 no.3
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• pp.384-390
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• 2010

Since many accidents have been constantly occurring in the workplace, requirements of Industrial Safety Management have also been increasing. In order to meet the needs and prevent the problems in advance, we designed wireless sensor network system based on PLC. This system is set with amain node including PLC Modem and Zigbee in the every workplace and each wireless sensor node is attached to every worker in the workplace. The main node is supposed to transmit and receive sensor data, and the data which is from a wireless sensor node to the main node is delivered to monitoring PC through PLC. In this paper, it is expected that, by perceiving the realtime situation of the work place through this system, we could prevent the problems in advance and reduce damages by accidents.

• Korean Institute of Interior Design Journal
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• v.21 no.1
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• pp.68-77
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• 2012

Appreciating the aspect of modem architecture requires not only the comprehension of the nature of design and architects' ways of thinking and expression but also observers' views on buildings and their perceptive/cognitive stages. This calls for an in-depth study on the "system of phenomenological perceptions" that works as a new architectural experience system. The system of phenomenological perceptions makes it possible to specify the individual process of understanding architecture, that is, hands-on experiences, participations, feelings, perceptions, and cognition. The value of user experience and cognition has been emphasized by philosophical and aesthetical concepts as well. Therefore, in order to better appreciate the modern architecture, this study suggests theoretical consideration to "orientation and event" that are crucial elements in understanding a phenomenological view and materializing actual space formation. This offers the cognitive system with which we analyze modem architecture and comprehensive expressional methods. In other words, this study contemplates the system of phenomenological perceptions from an existential spatial perspective by structurizing the system of the orientation and the event in order to segmentalize users' current locations, potential directions, the relations with spaces, continual vie'wpoints as well as buildings' functions and interior and exterior division. The system of phenomenological perceptions helps understand and systemize modern architecture through a system based on relations between sensation, perception, cognition, sensitivity, and rationality. This creates a new cognitive system employing the concept of the orientation and the event, which is different from a normal cognitive system basing on the sense of vision. When observers appreciate space, they tend to relate the space to a certain event and to remember their experiences in it. During the process, they draw borders of the space in which the event takes place and give shape to their experiences including actions, movements, cognition and sensation. The process leads to the formation of "placeness," and here, the concept of the orientation comes in as the location and the center of the placeness. This study proves that a determined orientation coupled with individual experience and events settles the place ness; detailed elements in the cognitive system have close relations with one another; the orientation, actions, events, and places are the factors that materialize observers' architectural experience.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.11 s.353
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• pp.95-117
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• 2006

In this paper, we describe the optimization of the link-level performance and the complexity of floating-point and fixed-point methods in IEEE 802.16e OFDMA/TDD mobile modem. In floating-point design, we propose the channel estimation methods for downlink traffic channel and select the optimized method using computer simulation. So we also propose efficent algorithms for time and frequency synchronization, Digital Front End and CINR estimation scheme to optimize the system performance. Furthermore, we describe fixed-point method of uplink traffic and control channels. The superiority of the proposed algorithm is validated using the performances of Detection, False Alarm, Missing Probability and Mean Acquisition Time, PER Curve, etc. For fixed-point design, we propose an efficient methodology for optimized fixed-point design from floating-point At last, we design fixed-point of traffic channel, time and frequency synchronization, DFE block in uplink and downlink. The tradeoff between performance and complexity are optimized through computer simulations.

• Journal of the Korean Home Economics Association
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• v.43 no.4 s.206
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• pp.173-185
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• 2005

The purposes of this study were to determine the general trends of the family value orientations FVO of overseas Korean women, to investigate differences in related variables, and to examine the relationships between FVO and the related variables. The subjects were 1,413 Korean women over 20 years living abroad in America (363 women), China (555), and Russia Central Asia (495 women). The subjects completed a questionnaire on FVO. Data were analyzed using SPSS. The major findings were as follows: 1. Korean-American women's FVO were modernistic, Korean chinese women's were traditional, and Korean women in Russia Central Asia showed neither traditional nor modem FVO. 2. The overseas Korean women's values were different from the value's dimension. 'Filial piety' showed very traditional value orientations, but 'preference of son , and 'mate selection 'showed modem FVO. The dimensions of FVO were different according to the living region. 3. The FVO values were different according to age, and period of education. Korean-American women's FVO were positively related to age, health condition, and the cognition of being Korean. Korean-Chinese women's FVO were related to age, living condition, marital and parent-child relationship, self-respect, and life satisfaction. Russia Central Asia women's FVO were correlated with age, period of education, living condition, health condition, the cognition of being Korean, marital and parent-child relationship, self-respect, and depression.

• Journal of the Korea Furniture Society
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• v.20 no.1
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• pp.21-30
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• 2009

This research is conducted on temporary street furniture, which is one of the significant factors that comprise the street landscape in modem cities. The primary purpose of this research is to present the guidance on direction of planning by examining the design and installation types of construction and screen fences usually established at construction sites for buildings, roads, parks and etc. The results are as follows: 1. The construction and screen fences at construction sites of urban areas used to be a mere tentative facility to prevent noise and safety accidents but have now incremented their roles to serve not only as a functional but also as an aesthetic element with a city view and harmonization with other elements taken into consideration. In particular, it is noticeable that, based on its unique feature of tentativeness, its role has developed to serve as street furniture that adds variability to the modem city. 2. There are two different types of screen fences: blackout type and transparent type. The transparent screen turns out to be used a lot at the construction site of building a skyscraper or differentiated building in downtown city area or in places where there are buildings of similar types and shapes located along the street in the vicinity of the construction site. 3. The actual cases of adopting the tentative construction and screen fences all at the same time as a single unit have been found in historically and culturally significant architectures with the screen design used to demonstrate the view after completion of construction or the characteristics of the architecture.

• Journal of the Korean Geographical Society
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• v.39 no.1
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• pp.70-87
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• 2004

This paper is to conceptualize 'new urbanization' on the basis of a certain possibility of 'sustainable urbanization' in the capitalist society, while admitting some criticism on its possibility. For this purpose, first of all, this paper points out some economic and environmental difficulties in the Fordist regime of accumulation and the developmentalist strategies which have promoted the modem urbanization in the industrial society. Then, this paper examines the concept of 'sustainable development' which has been suggested to manage such problems in modem industrial cities, and explores its limitation that the application of this concept has been usually confined to some ex post facto - that is, weak sustainable development - strategies to resolve urban environmental problems. Finally, in order to overcome these problems both of developmentalism and of weak sustainable development, this paper conceptualize strong sustainable development for new urbanization and suggest urban environmental strategies for strong sustainable cities.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.8
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• pp.14-25
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• 2002

In this paper, we propose a modified AFC algorithm which is suitable for the implementation of WCDMA reverse link receiver modem. To reduce the complexity, the modified CP-FDD algorithm named 'Normalized CP-FDD' is applied to the AFC loop. The proposed FDD algorithm overcomes the conventional CP-FDD's sensitivity to the variance of input signal amplitude and increases the linear range of S -curve. Therefore, offset frequency estimation using the proposed scheme can be more stable than the conventional method. Unlike IS-95, since pilot symbol in WCDMA is not transmitted continuously, we introduce a moving average filter at the FDD input to increase the number of cross-product. So, tracking speed and stability are improved. For more rapid frequency acquisition and tracking, we adopt a multi-stage tracking mode. Using NCO having ROM table structure, the frequency offset is compensated. We applied the proposed algorithm in the implementation of WCDMA base station modem successfully.