• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.107-110
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• 2015

In this paper, we propose a coalitonal game theoritic approach to the power control problem in resource-constrained wireless sensor networks, where the objective is to enhance power efficiency of individual sensors while providing the QoS requirements. We model this problem as two-sided one-to-one matching game and deploly deferred acceptance procedure that produces a single matching in the core. Furthermore, we show that, by applying the procedure repeatedly, a certain stable state is achieved where no sensor can anticipate improvements in their power efficiency as far as all of them are subject to their own QoS constraints. We evaluate our proposal by comparing them with cluster-based and the local optimal solution obtained by maximizing the total system energy efficiency, where the objective function is non-convex.

• Journal of KIISE:Software and Applications
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• v.28 no.3
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• pp.224-238
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• 2001

본 논문은 ATM(Abstract Timed Machine)으로 명세된 실시간 시스템을 검증하기 위한 방법을 기술한다. ATM은 임무 위급 시스템인 실시간 시스템을 명세, 분석, 검증하기 위한 정형기법이다. ATM은 모드와 전이, 포트로 구성되어 있으며 모드는 머신의 압축된 상태를 표현한다. 전이는 하나의 모드에서 다른 모드로의 전환을 나타내며 조건과 이벤트로 구성되어 있다. 포트는 ATM간의 상호작용을 위한 진입을 표현한다. 다른 정형기법과 비교하여 ATM은 소프트웨어의 순환공학 과정에서 사용하기 위해 설계되었다. 역공학 측면에서 볼 때 ATM은 계산 논리뿐만 아니라 실시간 시스템의 실제 소스코드에 있는 설계나 환경정보를 표현할 수 있다. 이러한 목적을 위해 ATM의 모드는 계산모드, 추상화 모드, 주제모드로 구분된다. 계산 모드는 코드 상에서의 논리와 계산을 나타내며 추상화 모드는 모드와 전이의 블록을 하나의 ATM으로써 표현한다. 대개의 경우, 이것은 코드 상에서의 블록을 ATM내 하나의 모드로 나타낼 때 사용한다. 주제 모드는 예외나 주기적 동작 등과 같은 다수의 ATM의 주제를 표현한다. 실시간 시스템을 검증하기 위해 시스템의 소스 코드는 역명세 과정을 통하여 ATM으로 표현된다. 검증은 ATM에 대한 도달성 그래프를 생성하는 것에 의해 수행된다. 도달성 그래프는 상태와 시간을 추상화되고 압축된 형태로 표현할 수 있으며 그 결과 시간 속성을 지닌 상태 공간을 감소시킬 수 있다. 또한 시스템의 교착상태를 쉽게 발견할 수 있다. 본 논문은 ATM과 실행 모델, 도달성 그래프, 검증을 위한 속성 등을 기술하며 이들을 다른 정형 방법들과 예제를 통하여 비교한다.수 있다. 모피우스는 헤더나 광고와 같은 불필요한 정보들을 제거하는 별도의 단계를 거치지 않으므로 wrapper를 빠르게 생성한다. 궁극적으로 모피우스는 새로운 웹 상점을 사용자가 자유롭게 추가, 삭제할 수 있는 환경을 제공한다.X>와 반응시킬 경우에는 반응식 c에 의거 진행됨을 예측할 수 있었다.의거 진행됨을 예측할 수 있었다.이 거의 산화되지 않았고, $700^{\circ}C$에서도 ZnS와 ZnO 상이 공존한 것으로 보아 SnO$_2$코팅이 ZnS의 산화를 억제하는 것으로 나타났다.pplied not only to the strike system in the RSC circle, but also to the logistics system in the SLC circle. Thus, the RSLC model can maximize combat synergy effects by integrating the RSC and the SLC. With a similar logic, this paper develops "A Revised System of Systems with Logistics (RSSL)" which combines "A New system of Systems" and logistics. These tow models proposed here help explain several issues such as logistics environment in future warfare, MOE(Measure of Effectiveness( on logistics performance, and COA(Course of Actions)

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.183-189
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• 1991

The present study was performed to elucidate the factors which modulate uterine prostaglandin synthesis during the implantation period in rats, by employing delayed implantation model. Administration of estradiol sharply increased uterine cAMP concentration 4 hrs later during the delayed implantation process. Concentrations of uterine PGE and $PGF_2{\alpha}$ were increased at 12 hrs after the estradiol treatment although an increase in $PGF_2{\alpha}$ was not statistically significant. The concomitant treatment of indomethacin with estradiol significantly suppressed estradiol-induced PGE and $PGF_2{\alpha}$ at 12 hrs, while uterine cAMP concentration was not suppressed. The treatment of dbcAMP without estradiol gradually increased uterine PGE and $PGF_2{\alpha}$ showing the maximum 8 hrs later, suggesting that cAMP minics estradiol effect on uterine prostaglandin synthesis during the implantation process. Furthermore, the pretreatment of theophylline, phosphodiesterase inhibitor, induced significantly greater concentrations of uterine PGE and $PGF_2{\alpha}$, compared with estradiol-only treated group. These results suggest that estradiol stimulates uterine prostaglandin synthesis and this process may be mediated by an elevation of cAMP during the delayed implantation process in rats.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.89-96
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• 2011

In this study, increasing the range of replacement rate of FA with concrete properties were analyzed to provide basic data of FA replacement 0-40 % and curing temperature $5-35^{\circ}C$ range. As a result of the increased fluidity in proportion to the increase in FA, but decreased air. Setting time delayed at replacement rate increases and low temperature, simple insulation temperature history of the FA up to 40 % replacement rate increases the maximum temperature was low $8^{\circ}C$, the highest temperature reaching time delay of 13 hours. FA replacement up stream of the curing temperature, compressive strength compared to the higher plane, it was found that improved strength development. In carbonation tests with increasing the replacement ratio of FA carbonation depth was increased. Therefore, continued research on carbonation measures was to be necessary.

• Journal of the Korea Concrete Institute
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• v.27 no.3
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• pp.265-272
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• 2015

In this study, a method to reduce temperature rise due to hydration in mass concrete is investigated. It is to use retarder (glucose) for reducing heat of hydration and to use calcium silicate hydrate (C-S-H) for compensating the retardation effect due to its role as a nucleation seed. For this purpose, the temperature rise of cement paste due to hydration was measured and the effect of using both C-S-H and glucose on setting and 28-day compressive strength of mortar specimens was investigated. According to the experimental results, using C-S-H and glucose caused the reduction in the maximum temperature but accelerated the time to reach the maximum temperature compared to that of retarded cement paste using glucose. In addition, using C-S-H and glucose did not show significant effect on 28-day compressive strength of mortar specimens, indicating that the method shown in this study can be a successful alternative to control maximum temperature rise in mass concrete.

• Progress in Medical Physics
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• v.25 no.4
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• pp.248-254
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• 2014

The purpose of this study is to develope a control system for a small X-ray tube generator and investigate control methods for the X-ray generator. The small X-ray tube was developed for electronic brachytherapy, and thus, the new control method should be investigated, if the small X-ray tube is used for the imaging system. The Axxent S700 X-ray tube and the XF060NZZ485 high voltage generator were used to compose a X-ray imaging system and control board was developed by using AT90CAN128 MCU. The two control methods were investigated after tube voltage was set to 50 kV, one was filament current control method and the other was beam current control method. The former was subdivided into two methods according to the filament heating time, the 5 and the 10 seconds respectively. In the filament current method, the beam current did not rise up to the desired value, if the filament current had not been maintained for at least 10 seconds. The onset filament currents to generate beam current were varied from 1,300 to 1,350 mA and over 5 seconds were needed in order to reach the desired tube current value after beam current was generated. However, in the tube current control method, the beam current reached to the desired value without any time delay with the filament current of 1,500 mA. In this study, we found that the beam current control method was appropriate for the use of small X-ray tube developed for brachytherapy in the X-ray imaging system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.899-906
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• 1996

The physicochemical and microbiological studies were conducted to examine the effect of pineneedle(Pinu densinora Seib. et Zucc) sap on the Kimchi fermentation. Kimchi with the addition of various levels(0, 0.5, 1.0, or 1.5%) of pine needle sap was fermented either at $4^{\circ}C$ for 15 days after placing at room temperature for 24 hours(Group A) or at $15^{\circ}C$ for 15 days(Group B). pH reached the optimal value of Kimchi fermentation(pH 4.2) on day 3 and day 4~7 in 0% treatment and pine needle sap treatments, respectively, which indicated that shelf-life of Kimchi was extended by 1~4 days by the addition of pine needle sap. Total acidity was decreased by the addition of pine needle sap. More rapid decrease in pH and increase in total acidity were observed in Group B than in Group A. Reducing sugar content was reduced to approximately 80% by day 4~5 in all treatments. Total vitamin C content was reached peak on day 1 of fermentation and then decreased in all treatments. Reducing sugar and total vitamin C contents were slightly increased by the addition of pine needle sap due to the components present in pine needle sap. Total viable cell number rapidly increased to reach Peak on day 3 and then slowly decreased during the fermentation. However, total viable cell number as well as reducing sugar and total vitamin C contents did not differ between Group A and Group B. In Group A, Lactobacillus cell number in 0% treatment continued to increase to reach peak on day 9, while the numbers in pine needle sap treatments reached Peak on day 5~9 and then gradually decreased throughout the fermentation. Unlike in Group A, Lactobaillus cell numbers in pine needle sap treatments in Group B continued to increase to reach Peak on day 7. As pine needle sap levels increased, total viable cell number and Lactobacillus cell number decreased regardless of fermentation temperatures. The results of this study indicate that pine needle sap causes to delay the Kimchi fermentation by slowing down pH drop and inhibiting the Lactobacillus cell growth.

• The Journal of the Acoustical Society of Korea
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• v.20 no.4
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• pp.22-28
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• 2001

This paper describes the implementation of a robust speaker position location system using the voice signal received by microphone array. To be robust to the reverberation which is the major factor of the performance degradation, low-frequency phase restoration algorithm which eliminates the influence of reverberations using the low-frequency information of the CPSP function is proposed. The implemented real-time system consists of a general purpose DSP (TMS320C31 of Texas instruments), analog part which contains amplifiers and filters, and digital part which is composed of the external memory and 12-bit A/D converter. In the real conference room environment, the implemented system that was constructed by the proposed algorithms showed better performance than the conventional system. The error of the TDOA estimation reduced more than 15 samples.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1005-1010
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• 1999

To study the shortening of rigor mortis and changes in the morphological properties of gamma-irradiated pre-rigor bovine muscle (M). Sternomandibularis during post mortem, this experiment was performed with a test of shear force and the observation of the ultrastucture of raw muscle. The time elapsed until maximum shear force values was shortened by gamma irradiation, depending upon the dose. The release of rigor mortis started earlier than control (non-irradiated muscle). A shortening of the length of the Z-line and the maintenance of the sarcomere length by gamma irradiation was observed. The breakdown of the perimysium of muscle bundles was observed more in irradiated samples than in the control. In conclusion, it is considered that gamma irradiation on pre-rigor beef shortens aging-period, improves tenderness and enhances the beef quality.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1080-1084
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• 2007

Many different methods for sound source localization have been developed. Most of them mainly depend on time delay of arrival (TDOA) or on empirical or analytic head related transfer functions (HRTFs). In real implementation, since the direct path between a source and a sensor is interrupted by obstacles as like a head or body of robot, it has to be considered the number of sensors as well as their positions. Therefore, in this paper, we present the methods, which are included sensor position problem, to localize the sound source with 4 microphones to cover the 3D space. Those are modified two-step TDOA methods. Our conclusion is that the different method has to be applied in case to be different microphone position on real robot platform.