• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.2
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• pp.21-34
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• 2002

In this paper we propos a new hardware architecture of modular exponentiation using a division chain method which has been proposed in (2). Modular exponentiation using the division chain is performed by receding an exponent E as a mixed form of multiplication and addition with divisors d=2 or $d=2^I +1$ and respective remainders r. This calculates the modular exponentiation in about $1.4log_2$E multiplications on average which is much less iterations than $2log_2$E of conventional Binary Method. We designed a linear systolic array multiplier with pipelining and used a horizontal projection on its data dependence graph. So, for k-bit key, two k-bit data frames can be inputted simultaneously and two modular multipliers, each consisting of k/2+3 PE(Processing Element)s, can operate in parallel to accomplish 100% throughput. We propose a new encoding scheme to represent divisors and remainders of the division chain to keep regularity of the data path. When it is synthesized to ASIC using Samsung 0.5 um CMOS standard cell library, the critical path delay is 4.24ns, and resulting performance is estimated to be abort 140 Kbps for a 1024-bit data frame at 200Mhz clock In decryption process, the speed can be enhanced to 560kbps by using CRT(Chinese Remainder Theorem). Futhermore, to satisfy real time requirements we can choose small public exponent E, such as 3,17 or $2^{16} +1$, in encryption and verification process. in which case the performance can reach 7.3Mbps.

• Journal of the Korean Society of Clothing and Textiles
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• v.10 no.1
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• pp.1-8
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• 1986

This study was undertaken to explore the relationship between the personality characteristic (the self-esteem) and tao clothing behaviors according to the sex and the five environmental variables. This study was designed with the hypothetic model regarding the age and the five environmental variables as Independent Variable, the self-esteem as Intervening Variable, the eight clothing behaviors as Dependent Variable. For the testing hypothesis, the questionnaries were adminstered to 335 high school boys and 308 high school girls in Pusan. The data was analyzed statistically at the B.N.U. Computer Center using to the Path Analysis (by Multiple Regression Analysis Method). The results were as follows : 1. There was significant difference in the self-esteem according to the sex. Boys had higher scores than girls. 2. There was no significant relationship between the self-esteem and all the environmental variables of this study. 3. There were significant differences in the clothing behavior subscales according to the sex. Girls had higher scores than boys in every clothing behavior subscales. 4. There were partial relationship between the clothing behavior subscales and the environmental variables. 5. There was a highly significant relationship between the self-esteem and the clothing behavior subscales except Comfort and Modesty. A negative significant aubscale were Interest, Psychological Dependence, Social Approval and Special Attention. 6. There were positively significant relationship among the clothing behavior subscales except Modesty-Aesthetics, Modesty-Interest, Modesty-Psychological Dependence and Modesty-special Attention.

• KIEE International Transactions on Electrophysics and Applications
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• v.2C no.6
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• pp.281-286
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• 2002

The temperature accelerated dielectric breakdown strength of on-wafer low-k dielectric polymer films with thicknesses ranging from 94 nm to 1141 nm is investigated by using the current-voltage characteristic measurements with MIS structures. The temperature dependence of dielectric strength is demonstrated to be Arrhenious for all thicknesses. However, the activation energy is found to be strongly thickness dependent. It follows an exponential relationship rather than being a single value, i.e., the activation energy increase significantly as film thickness increases for the thickness below 500 nm, but it is almost constant for the thickness above 500 nm. This relationship suggests that the change of the activation energy corresponding to different film thickness is closely related to the temperature dependence of the electron trapping/detrapping process in polymer thin films, and is determined by both the trapping rate and the detrapping rate. Thinner films need less energy to form a conduction path compared to thicker films. Hence, it leads to smaller activation energy in thinner films, and the activation energy increases with the increase in film thickness. However, a nearly constant value of the activation energy is achieved above a certain range of film thickness, indicating that the trapping rate and detrapping rate is almost equal and eventually the activation energy approaches the value of bulk material.

• ETRI Journal
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• v.42 no.4
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• pp.575-584
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• 2020

Electromagnetic (EM) waves used to send signals under seawater are normally restricted to low frequencies (f) because of sudden exponential increases of attenuation (𝛼) at higher f. The mathematics of EM wave propagation in seawater demonstrate dependence on relative permeability (𝜇_r), relative permittivity (𝜀_r), conductivity (𝜎), and f of transmission. Estimation of 𝜀_r and 𝜎 based on the W. Ellison interpolation model was performed for averaged real-time data of temperature (T) and salinity (S) from 1955 to 2012 for all oceans with 41 088 latitude/longitude points and 101 depth points up to 5500 m. Estimation of parameters such as real and imaginary parts of 𝜀_r, 𝜀_r', 𝜀_r", 𝜎, loss tangent (tan 𝛿), propagation velocity (V_p), phase constant (𝛽), and α contributes to absorption loss (L_a) for seawater channels carried out by using normal distribution fit in the 3 GHz-40 GHz f range. We also estimated total path loss (L_PL) in seawater for given transmission power P_t and antenna (dipole) gain. MATLAB is the simulation tool used for analysis.

• Korean journal of communication and information
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• v.38
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• pp.245-275
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• 2007

This study analyzes interactivity between formal policy and informal trade practices at outside production market of broadcasting production environment in Korea. For this, this study raises three topics. First, the trait of historical context of policy making at outside broadcasting production policy: Second, the trait and meaning of path dependency behavior in the process of trade practices between over-the-air TV Organization and independent production companies : Three, the meaning of interactivity between formal policy and informal trade practices at outside broadcasting production market. Major findings of this study are : the trait of policy making was concentrated on the quantitative rates of the outside production program. And, the trait of trade practices was unfair rivalry in accordance with the custom of insider dealing. The chief cause of the conflict structure of outside broadcasting production market is lacked in policy complement at the qualitative dimension.

• Tribology and Lubricants
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• v.33 no.1
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• pp.1-8
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• 2017

Drag torque reduction in a wet clutch pack is a key aspect of the design process of the dual clutch transmission (DCT) system. In order to reduce the drag torque caused by lubricant shear resistance, recently developed wet clutch pack systems of DCT, as well as automatic transmission and other four-wheel drive (4WD) couplings, frequently utilize wavy wet clutch pads. Therefore, wavy shape of friction pad are made on the groove patterns like waffle pattern for the reduction of drag torque. Additionally, the groove patterns are designed with larger channels at several locations on the friction pad to facilitate faster outflow of lubricant. However, channel performance is a function of the waviness of the friction pad at the location of the particular channel. This is because the discharge sectional area varies according to the waviness amplitude at the location of the particular channel. The higher location of the additional channel on the friction pad results in a larger cross-sectional area, which allows for a larger flow discharge rate. This results in reduction of the drag torque caused by the shear resistance of DCTF, because of marginal volume fraction of fluid (VOF) in the space between the friction pad and separator. This study computes the VOF in the space between the friction pad and separator, the hydrodynamic pressure developed, and the shear resistance of friction torque, by using CFD software (FLUENT). In addition, the study investigates the dependence of these parameters on the location and waviness amplitude of the channel pattern on the friction pad. The paper presents design guidelines on the proper location of high waviness amplitude on wavy friction pads.

• Journal of Korea Spatial Information System Society
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• v.10 no.1
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• pp.51-63
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• 2008

Previous studies for routing In USN (Ubiquitous Sensor Networks) appear to be unreliable due to the dependence on non-spatial data and the lack of map overlay analysis. Multiple spatial parameters and radio propagation modeling techniques were integrated to derive RSSI (Received Signal Strength Indicator) value between route nodes and produce a highly reliable path map. It was possible to identify area-wide patterns of USN route subject to many different Influences (e.g. the specific effects of radio blocking factors such as the visible area, road area, cell duplicated area, and building density), which cannot be acquired by traditional non-spatial modeling. The quantitative evidence concerning the USN route for individual cell as well as entire study area would be utilized as major tools to visualize paths in real-time and to select alternative path when failure or audition of route node occurs.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.1
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• pp.42-49
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• 2016

In this paper, we design and fabricate an instantaneous frequency measurement receiver with a frequency resolution of 125 MHz which detects and measures continuous signals in 4~6 GHz using path difference of delay lines. The receiver has a 4-bit configuration and consists of power dividers, delay lines, power combiners, power detectors, voltage comparator circuits and so on. The accuracy of the instantaneous frequency measurement is improved by applying offset voltage compensation to the comparator circuits to compensate the frequency-dependent path loss of the delay line and the frequency dependence of power detection.

• Journal of the Economic Geographical Society of Korea
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• v.23 no.1
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• pp.110-123
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• 2020

The advanced industrial economies have been suffering from rapid de-industrialization since the 1970s. In order to overcome such crisis, many countries have attempted to establish science parks and technopoles. Sophia Antipolis in France is one of the best examples of the worldly known technopoles, which was launched in the late 1960s. However, earlier evaluations on the technopole were not positive, while there were no dynamic innovative activities among institutions and firms of the technopole at least up to the early 1990s. While some changes in such circumstance have been observed since then, this paper attempts to investigate the changes and transformations occurring from the technopole since the late 1990s. Based on the review of the recent publications, statistics and expert interviews, the current paper concludes that Sophia Antipolis has been transformed into a dynamic and innovative technopole.

• Journal of the Economic Geographical Society of Korea
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• v.25 no.4
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• pp.583-599
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• 2022

According to the discussion on the low-density economy in OECD industrial growth in remote area has played a central role in the members'economic recovery from the financial crisis in the mid-2000s. Based on the OECD's low-density economy this study examines the phenomena and spatial characteristics of industrial growth in peripheral areas of Korea. The growth of industries in the peripheral areas shows a similar growth characteristics as cases in the OECD members. Various manufacturing and service sectors as well as traditional sectors such as agriculture, forestry and fishing have grown in the peripheral areas since the mid-2000s. Firms in the peripheral areas form various cooperative networks to overcome the unfavorable regional conditions. The growth of new industries shows the possibility of path-dependent development in the periphery. Based on the results, implications on the policies for supporting the diversification of regional industries, setting flexible regional boundaries for policies, and linking policy sectors are derived.