• Restorative Dentistry and Endodontics
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• 제28권2호
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• pp.134-145
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• 2003

Mechanical properties and microleakage of two composites [conventional hybrid type DenFil (VERICOM Co., Anyang, Korea) / micro matrix hybrid type Esthet X (Dentsply Caulk, Milford, DE, U.S.A.)] were evaluated to assess whether variable light intensity curing is better than conventional curing technique. Curing was done for 40 seconds in two ways of 2 step soft-start technique and 5 step ramping technique. Three kinds of light intensities of 50, 100, $200{\;}mW/\textrm{cm}^2$ were initially used for 10, 20, 30 seconds each and the maximum intensity of $600 {\;}mW/\textrm{cm}^2$ was used for the rest of curing time in a soft-start curing tech nique. In a ramping technique, curing was done with the same initial intensities and the light intensity was increased 5 times with the same rate to the maximum intensity of $600{\;}mW/\textrm{cm}^2$. After determining conditions that showed no different mechanical properties with conventional technique, Esthet X composite was filled in a class V cavity, which dimension was $4{\times}3{\times}1.5{\;}mm$ and cured under those conditions. Microleakage was evaluated in two ways of dye penetration and maximum gap estimation through SEM observation. ANOVA and Spearman's rho test were used to confirm any statistical significance among groups. The results were as follows : 1 Several curing conditions of variable light intensities resulted in the similar mechanical properties with a conventional continuous curing technique, except conditions that start curing with an initial light intensity of $50{\;}mW/\textrm{cm}^2$. 2. Conventional and ramping techniques were better than soft-start technique in mechanical properties of microhardness and compressive strength. 3. Soft-start group that started curing with an initial light intensity of $100{\;}mW/\textrm{cm}^2$ for 10 seconds showed the least dye penetration. Soft-start group that started curing with an initial light intensity of $200{\;}mW/\textrm{cm}^2$ for 10 seconds showed the smallest marginal gap, if there was no difference among groups. 4. Soft-start technique resulted in better dye-proof margin than conventional technique(p=0.014) and ramping technique(p = 0.002). 5. There was a very low relationship(p=0.157) between the methods of dye penetration and marginal gap determination through SEM evaluation. From the results of this study, it was revealed that ramping technique would be better than conventional technique in mechanical properties, however, soft-start technique might be better than conventional one in microleakage. It was concluded that much endeavor should be made to find out the curing conditions, which have advantages of both aspects or to solve these kinds of problems through a novel idea of polymerization.

• Journal of Electrical Engineering and Technology
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• 제4권3호
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• pp.353-359
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• 2009

This paper proposes a novel technique for calculating the security costs that properly includes ramping constraints in the operation of a deregulated power system. The ramping process is modeled by a piecewise linear function with certain assumptions. During this process, a ramping cost is incurred if the permissible limits are exceeded. The optimal production costs of the power producers are calculated with the ramping cost included, considering a time horizon with N-1 contingency cases using contingency constrained optimal power flow (CCOPF), which is solved by the primal-dual interior point method (PDIPM). A contingency analysis is also performed taking into account the severity index of transmission line outages and its sensitivity analysis. The results from an illustrative case study based on the IEEE 30-bus system are analyzed. One attractive feature of the proposed approach is that an optimal solution is more realistic than the conventional approach because it satisfies physical constraints, such as the ramping constraint.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1424-1425
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• 2006

A four-step rapid thermal annealing (RTA) process is proposed in order to improve the throughput and stabilize the process, compared to the six-step RTA process. Effects of annealing on the properties of a structure mode of CMOS process in both cases were investigated. The implanted dopant(As, $BF_2$ and Ti/TiN) movement in silicon during different rapid thermal annealing conditions was studied using secondary ion mass spectroscopy (SIMS) technique. These results show that the four-step RTA process significantly improves time effect and throughput (15%) by the condition of ramping up compared to the six-step RTA process.

• JSTS:Journal of Semiconductor Technology and Science
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• 제1권2호
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• pp.125-131
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• 2001

When the program voltage is applied to a word line, a part of the boosted channel charge in inhibited bit lines is lost due to the coupling between the string select line (SSL) and the adjacent word line. This phenomenon causes the program disturbance in the cells connected to the inhibited bit lines. This program disturbance becomes more serious, as the word line pitch is decreased. To reduce the word line coupling, the rising edge of the word-line voltage waveform was changed from a pulse step into a ramp waveform with a controlled slope. The word-line ramping circuit was composed of a timer, a decoder, a 8 b D/A converter, a comparator, and a high voltage switch pump (HVSP). The ramping voltage was generated by using a stepping waveform. The rising time and the stepping number of the word-line voltage for programming were set to $\mutextrm{m}-$ and 8, respectively,. The ramping circuit was used in a 512Mb NAND flash memory fabricated with a $0.15-\mutextrm{m}$ CMOS technology, reducing the SSL coupling voltage from 1.4V into a value below 0.4V.

• 한국응용곤충학회지
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• 제53권1호
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• pp.73-80
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• 2014

수확 후 해충방제가 국내 수요 농산물은 물론이고 검역 문제를 해결하기 위한 수출용 농산물에 대해서 요구되고 있다. 특별히 유기 농산물 또는 환경친화형 재배 농산물에 대해서 메틸브로마이드와 같은 화합물을 이용한 기존의 수확 후 처리기술은 의미를 잃게 되었다. 대체 기술로서 CATTS (환경조절열처리기술)라 명명된 물리적 처리기술이 개발되어 사과와 여러 핵과류 과실을 가해하는 곤충과 응애에 적용되고 있다. 본 연구는 국내 사과 수출을 위해 수입국에서 규제하는 복숭아순나방(Grapholita molesta)을 대상으로 CATTS 처리 조건을 결정하는 데 목표를 두었다. 이 해충에 CATTS를 적용하기 위해 사과 과실에 잔류하면서 열에 높은 내성을 보이는 발육시기를 분석하였다. 열처리 조건($44^{\circ}C$, 20분)에서 5령 유충이 가장 높은 내성을 보였다. 환경조건(15% $CO_2$, 1% $O_2$)에서 기기 내부 온도가 $25^{\circ}C$에서 $46^{\circ}C$까지 증가하는 시기를 CATTS 가열단계로 볼 때, 이 가열 속도가 빠를수록 CATTS 해충 방제 효과가 높았다. 또한 가열단계 후 CATTS 처리 시간이 길수록 CATTS 효율이 증가했다. 특히 가열단계에서 과실 내부온도가 $44^{\circ}C$로 이르게 하는 것이 CATTS 효율을 높이는 데 결정적이었다. 이러한 조건들을 종합하여 CATTS 표준 처리기술을 결정하였으며, 이 기술은 2,104 마리의 5령을 포함한 4,378 마리 복숭아순나방 유충 피해를 받은 사과에 대해서 100% 방제 효과를 나타냈다.