• ETRI Journal
• /
• v.41 no.3
• /
• pp.383-395
• /
• 2019

Clock Controlled Dual keeper Domino logic structures (CCDD_1 and CCDD_2) for achieving a high-speed performance with low power consumption and a good noise margin are proposed in this paper. The keeper control circuit comprises an additional PMOS keeper transistor controlled by the clock and foot node voltage. This control mechanism offers abrupt conditional control of the keeper circuit and reduces the contention current, leading to high-speed performance. The keeper transistor arrangement also reduces the loop gain associated with the feedback circuitry. Hence, the circuits offer less delay variability. The design and simulation of various wide fan-in designs using 180 nm CMOS technology validates the proposed CCDD_1 and CCDD_2 designs, offering an increased speed performance of 7.2% and 8.5%, respectively, over a conventional domino logic structure. The noise gain margin analysis proves good robustness of the CCDD structures when compared with a conventional domino logic circuit configuration. A Monte Carlo simulation for 2,000 runs under statistical process variations demonstrates that the proposed CCDD circuits offer a significantly reduced delay variability factor.

• The Journal of Fisheries Business Administration
• /
• v.46 no.3
• /
• pp.143-161
• /
• 2015

This study presents a comparative analysis on mackerel distribution process and price formation process, and investigation of price and margin between traditional markets and Large-scale discount store distribution channel. Through this, the study investigated distribution efficiency of each channel, and examined whether a difference of distribution efficiency leads to a difference of performance through the investigation of a difference of function and role between members of a wholesale market and vendor of Large scale discount store. The following are the results of this study. As a consequence of investigating supply and sum by distribution channel of mackerel, it appeared that mackerels shipped from port market are distributed into 9 consumption sites(Wholesale market, Large scale discount store, Institutional Food Service, etc.). In the comparison of distribution efficiency between traditional retail store and Large scale discount store 52.0% margin is formed in traditional retail store distribution channel and 43.1% margin is formed in Large scale discount store, and a distribution cost rate consists of 19.4% cost in a traditional retail store for fishery products and 18.1% cost in a Large-scale discount store. To analyze a difference of performance, the study examine a difference of role and function between vendor and Wholesale market company, wholesaler and middleman. Wholesale market company and middleman of wholesale market for consumer have slightly high or similar score in collection function, sorting function, evaluation function and financial function which are traditional and original. However, it was confirmed that vendor has a better score in other functions, that is, newly-demanded functions(ex : market frontier function, product development function, Integral Distribution Function, etc.).

• Aerospace Engineering and Technology
• /
• v.1 no.2
• /
• pp.45-50
• /
• 2002

A conceptual design on the link budget of TC&R RF subsystem which transfers command and telemetry data as RF signal between the ground system and the 2005SAT spacecraft is presented in this paper. In order to perform the analysis of the link budget, we divided the analysis process into two processes, i.e., uplink and downlink process. For the uplink the power flux density at the spacecraft and the margin of the command receiver are calculated. In the case of the downlink the downlink EIRP and the margin of C/ No and Eb / No at the ground station are calculated. Through the uplink performance analysis, the power at the command receiver has well efficient margin, and the margin of C/ No and Eb / No is also fully proper for the downlink case.

• Korean Journal of Agricultural Science
• /
• v.39 no.1
• /
• pp.43-51
• /
• 2012

Hanwoo, Korean cattle, is traditionally an important livestock to farmers and also important meat to consumers. Recently, to make more efficient production system and provide cheaper and high-quality hanwoo meat, the scale-up via brand is emphasized. However, the price of hanwoo is getting higher and the price increase is considered to occur due to marketing margins in the distribution process. In this study, factors affecting the hanwoo marketing margin are analyzed using 2004-2009 monthly data. In the Cochrane-Orcutt estimation of marketing margin, hanwoo production, other domestic production and import, income, output index, market share of major retailers, and market share of hanwoo brands shows statistical significance in the result. The results shows basic factors of the marketing margins to hanwoo and gives some implications to the management system of hanwoo brand like a sophisticated market segmentation and a differentiated promotion.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.55 no.7
• /
• pp.319-326
• /
• 2006

This paper proposes a novel fault-tolerant gait for Quadruped robots using energy stability margins. The previously developed fault-tolerant gaits for quadruped robots have a drawback of having marginal stability margin, which may lead to tumbling. In the process of tumbling, the potential energy of the center of gravity goes through a maximum. The larger the difference between the potential energy of the center of gravity of the initial position and that of this maximum, the less the robot tumbles. Hence this difference of potential energy, dubbed as Energy Stability Margin (ESM), can be regarded as the stability margin. In this paper, a novel fault-tolerant gait is presented which gives positive ESM to a quadruped robot suffering from a locked joint failure. Positive ESM is obtained by adjusting foot positions between leg swing sequences. The advantage of the proposed fault-tolerant gait is demonstrated in a case study where a quadruped robot with a failed leg walks on a even slope.

• Nuclear Engineering and Technology
• /
• v.48 no.3
• /
• pp.684-701
• /
• 2016

The Gaussian process model (GPM) is a flexible surrogate model that can be used for nonparametric regression for multivariate problems. A unique feature of the GPM is that a prediction variance is automatically provided with the regression function. In this paper, we estimate the safety margin of a nuclear power plant by performing regression on the output of best-estimate simulations of a large-break loss-of-coolant accident with sampling of safety system configuration, sequence timing, technical specifications, and thermal hydraulic parameter uncertainties. The key aspect of our approach is that the GPM regression is only performed on the dominant input variables, the safety injection flow rate and the delay time for AC powered pumps to start representing sequence timing uncertainty, providing a predictive model for the peak clad temperature during a reflood phase. Other uncertainties are interpreted as contributors to the measurement noise of the code output and are implicitly treated in the GPM in the noise variance term, providing local uncertainty bounds for the peak clad temperature. We discuss the applicability of the foregoing method to reduce the use of conservative assumptions in best estimate plus uncertainty (BEPU) and Level 1 probabilistic safety assessment (PSA) success criteria definitions while dealing with a large number of uncertainties.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.7
• /
• pp.122-129
• /
• 2014

Due to remarkable market growth of smart devices, higher performance and more functionalities are required for a core system-on-chip (SoC), and thus the power demand is rapidly increasing. However, aggressive shrink of CMOS transistor have brought severe process variations thereby adversely affected the performance and power consumption under strict power constraint. Voltage binning (VB) scheme is one of the effective post silicon tuning techniques, which can reduce parametric yield loss due to process variations by adjusting supply voltage. In this paper, an optimal supply voltage tuning based voltage binning technique is proposed to reduce average power without an additional yield loss. Considering the different LVCC margins of process corners along with speed and leakage characteristics, the proposed method can optimize the deviation of voltage margin and thus save power consumption. When applying on a 30nm mobile SoC product, the experimental results showed that the proposed technique reduced average power consumption up to 6.8% compared to traditional voltage binning under the same conditions.

• Environmental and Resource Economics Review
• /
• v.26 no.4
• /
• pp.499-517
• /
• 2017

The purpose of this article is to show profit margin hedging can be an optimal strategy in crude oil purchasing. This study theoretically analyzes profit margin hedging strategy is optimal in crude oil purchasing using expected target utility function and conducts simulations to show if the profit margin hedging is profitable. In addition, this study tests existence of mean reversion of crude oil futures prices to confirm the theory that profit margin hedging is more profitable than other strategies, such as always hedging or buying at expiration with spot price, if futures prices are mean reverting. The simulation results show that the expected utility of profit margin hedging higher than other strategies. Although we cannot find any evidence that crude oil futures prices follow mean reverting process, we can conclude that profit margin hedging can be optimal strategy in crude oil purchasing based on theoretical proof and simulation results.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.4
• /
• pp.91-99
• /
• 2022

By applying METHOD 514.8 of the US military standard MIL-STD-810H, vibration analysis of the winding core automatic feeding device was performed during vehicle transportation. The contact point between the LM guide and main support frame was weak in the vertical axis, transverse axis, and longitudinal axis during the transportation of the automatic winding core feeder vehicle, and the maximum equivalent stress was 236.31 MPa in the longitudinal axis. When random vibration was applied, the safety margin in the longitudinal direction was 0.26, indicating low safety. The safety margin was changed by increasing the damage factor to 0.1. Finally, the safety margin was improved to 3.48 to secure safety. Resonance occurred with a Q factor of 9.34 in the harmonic response to which the RMS value of the ASD data was input, and the vertical axis safety margin was derived as 0.16. When the damping factor was 0.15, the Q factor was 3.37, and resonance was avoided with a safety margin of 6.62.

• Journal of Technologic Dentistry
• /
• v.23 no.2
• /
• pp.179-188
• /
• 2002

With regard to the manufacture of dental prosthesis, all the dental mechanism is of vital significance at the aspect of activating its function by fixing the prosthesis to Patient's oral cavity. However, if there we will take our immediate action without the discretion about its process none the less for the importance of dental mechanism, then we might have a serious problem. Accordingly, there need to pay attention to the dilatability makes up for the shrinkage state occurring by the feature of metal materials and manufacturing process which appeared in the process of dental mechanism, which eventually is expected to playa very important role in casting a dental prosthesis appropriate to one's oral tissue. This study was designed to take into account of the effects on margin consistency of prosthesis according to the continued time of casting-ring in the course of the casting of dental alloy. For this, the researcher made an experiment on the casting of dental alloy, its dilatability, and the change of phase. The results of this study were as follows: First, the researcher could see that the sample which was cast under the condition of $650^{\circ}C/20$ Minutes(the continued time) was far superior to others at the aspect of margin consistency. Second, according to the measurement of expansion coefficient by Dilatometer, the researcher perceived the fact that the expansion-coefficient showed a maximum of $37.1{\mu}m$ considering the sample's length which was cast with ordinary temperature under the condition of $650^{\circ}C/20$ Minutes. Third, from the result of X-ray diffraction under the condition of $650^{\circ}C/20$ Minutes(the continued time), the researcher could find that there's no difference between the change of phase and its intensity. As mentioned above, the researcher could ascertain the fact that its contraction don't give rise to the change of phase.