• 한국환경과학회지
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• 제18권11호
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• pp.1215-1224
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• 2009

This study evaluated the applicability of visible-light-driven N- and S-doped titanium dioxide($TiO_2$) for the control of low-level dimethyl sulfide(DMS) and dimethyl disulfide(DMDS). In addition, a photocatalytic unit(PU)-adsorption hybrid was evaluated in order to examine the removal of DMS and DMDS which exited the PU and a gaseous photocatalytic byproduct($SO_2$) which was generated during the photocatalytic processes. Fourier-Tranform-Infrared(FTIR) spectrum exhibited different surface characteristics among the three-types of catalysts. For the N- and S-doped $TiO_2$ powders, a shift of the absorbance spectrum towards the visible-light region was observed. The absorption edge for both the N- and S-doped $TiO_2$ was shifted to $\lambda$ 720 nm. The N-doped $TiO_2$ was superior to the S-doped $TiO_2$ in regards to DMS degradation. Under low input concentration(IC) conditions(0.039 and 0.027 ppm for DMS and DMDS, respectively), the N-doped $TiO_2$ revealed a high DMS removal efficiency(above 95%), but a gradual decreasing removal efficiency under high IC conditions(7.8 and 5.4 ppm for DMS and DMDS, respectively). Although the hybrid system exhibited a superior characteristic to PU alone regarding the removal efficiencies of both DMS and DMDS, this capability decreased during the course of a photocatalytic process under the high IC conditions. The present study identified the generation of sulfate ion on the catalyst surface and sulfur dioxide(maximum concentrations of 0.0019 and 0.0074 ppm for the photocatalytic processes of DMS and DMDS, respectively) in effluent gas of PU. However, this generation of $TiO_2$ would be an insignificant addition to indoor air quality levels.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제36회 동계학술대회 초록집
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• pp.262.2-262.2
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• 2009

• 한국정밀공학회지
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• 제25권7호
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• pp.13-18
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• 2008

• The Journal of the Acoustical Society of Korea
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• 제18권3E호
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• pp.21-25
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• 1999

This paper proposes methods that replace a missing triphone with a new one selected or created by existing triphones, and compares the results. The recognition system uses DMS (Dynamic Multisection) model for acoustic modeling. DMS is one of the statistical recognition techniques proper to a small - or mid - size vocabulary system, while HMM (Hidden Markov Model) is a probabilistic technique suitable for a middle or large system. Accordingly, it is reasonable to use an effective algorithm that is proper to DMS, rather than using a complicated method like a polyphone clustering technique employed in HMM-based systems. In this paper, four methods of filling missing triphones are presented. The result shows that a proposed replacing algorithm works almost as well as if all the necessary triphones existed. The experiments are performed on the 500＋ word DMS speech recognizer.

• 한국음향학회지
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• 제12권3호
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• pp.13-25
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• 1993

본 논문은 음성 다이얼링 시스템을 구현하기 위한 연결어 인식에 관한 연구이다. 적용된 인식 알고리즘은 기준패턴을 생성할 때 DMS 모델을 이용한 One-stage DMS/DP 알고리즘이고, 인식 대상어는 광운대학교 부서명 150 단어이다. 연결어 인식을 실시간으로 처리하기 위한 방법으로써 본 논문에서는 음절과 단어 단위의 DMS 템플리트를 구성하여 실험하였고 이 실험결과로부터 실시간과 인식률을 고려한 최적의 인식은 단어단위 템플리트에서 20 구간의 DMS 템플리트를 구성하여 실험하였고 이 실험결과로부터 실시간과 인식률을 고려한 최적의 인식은 단어단위 템플리트에서 20구간의 DMS 모델을 적용하였을 때 수행되었고, 이때 다중화자종속과 화자독립의 인식률은 각각 97.2%, 86.8%이다. 실험된 결과를 이용하여 음성 다이얼링 모델 시스템을 DSP 전용칩인 TMS320C30 프로세서를 내장한 DSP 보오드, 486 PC와 DIAL 모뎀을 이용해서 구현하였고, 전체 다이얼링 시간은 약 7~14초가 소요되었다.

• 한국대기환경학회지
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• 제13권5호
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• pp.355-360
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• 1997

The atmospheric concentration of dimethylsulfide (DMS), known as the predominant volatile organic. sulfur compound, is determined at subnanogram level by a combined application of non-cryogenic preconcentration method and gas chromatography with flame photometric detection (GC/FPD). The volatile DMS in air is preconcentrated using a trapping tube containing adsorbent like Molecular Sieve 5A (or gold-coated sands). The tube is then connected to the GC/FPD system via a six-way rotary valve, thermally desorbed at 40$0^{\circ}C$, separated on OV101 column, and detected by a flame photometric detector. The DMS peak elutes at about 2.5 mins and is integrated electronically. The analytical precision, if expressed in terms of relative standard error, is around 5%. The detection limit of our GC/FPD system is ca 1 ng of DMS. Details of our analytical system are presented.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.74-74
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• 2009

The ArF PR mask was. developed to overcome the limit. of sub 40nm patterning technology with KrF PR. But ArF PR difficult to meet the required PR selectivity by thin PR thickness. So need to the multi-stack mask such as amorphous carbon layer (ACL). Generally capacitively coupled plasma (CCP) etcher difficult to make the high density plasma and inductively coupled plasma (ICP) type etcher is more suitable for multi stack mask etching. Hybrid Coupled Plasma source (HCPs) etcher using the 13.56MHz RF power for ICP source and 2MHz and 27.12MHz for bias power was adopted to improve the process capability and controllability of ion density and energy independently. In the study, the oxide trench which has the multi stack layer process was investigated with the HCPs etcher (iGeminus-600 model DMS Corporation). The results were analyzed by scanning electron microscope (SEM) and it was found that etching characteristic of oxide trench profile depend on the multi-stack mask.

• 전기학회논문지
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• 제65권3호
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• pp.397-403
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• 2016

Generally, an electrical distribution configuration is a radial system with one-way current in a distribution management system (DMS). All feeders in a DMS have tie-switches to make radial system. Sometimes, DMS should change a tie-switch for operation. In that case, the tie-switch has to be closed first; then a switch is opened as another tie-switch in order to prevent blackout for customers. At the moment when the tie-switch is closed, distribution system is operated in a loop state, not radial. Before the loop operation, DMS operator has to check any expected events for stable distribution system operation; and the most important event is a mis-operation of a protection relay. In addition, DMS operator should check voltage profile violation but a calculation method of section voltages had not been used. Thus, this paper proposes a calculation method of section voltages at a loop operation in a DMS. The proposed calculation algorithm is verified by Matlap Simulink.

• Archives of Pharmacal Research
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• 제29권8호
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• pp.657-665
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• 2006

We recently reported that dimethylsphingosine (DMS), a metabolite of sphingolipids, increased intracellular pH and $Ca^{2+}$ concentration in U937 human monocytes. In the present study, we found that dimethylphytosphingosine (DMPH) induced the above responses more robustly than DMS. However, phytosphingosine, monomethylphytosphingosine or trimethylsphingosine showed little or no activity. Synthetic C3 deoxy analogues of sphingosine did show similar activities, with the C16 analogue more so than C18. The following structure-activity relationships were observed between DMS derivatives and the intracellular pH and $Ca^{2+}$ concentrations in U937 monocytes; 1) dimethyl modification is important for the DMS-induced increase of intracellular pH and $Ca^{2+}$, 2) the addition of an OH group on C4 enhances both activities, 3) the deletion of the OH group on C3 has a negligible effect on the activities, and 4) C16 appears to be more effective than C18. We also found that W-7, a calmodulin inhibitor, blocked the DMS-induced pH increase, whereas, KN-62, ML9, and MMPX, specific inhibitors for calmodulin-dependent kinase II, myosin light chain kinase, and $Ca^{2+}$-calmodulin-dependent phosphodiesterase, respectively, did not affect DMS-induced increases of pH in the U937 monocytes.

• 생명과학회지
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• 제32권9호
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• pp.667-677
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• 2022

돌산갓 종자를 원형, 찧은 형태, 볶은 형태로 각각 0.5 g (S-1), 1.0 g (S-2), 1.5 g (S-3) 첨가한 국물용 육수팩를 10분, 15분간 가열한 육수를 냉각한 후 품질적 특성을 측정하였다. 가열시간이 짧을수록 pH와 염도는 감소하는 경향을 나타냈다. 항산화활성은 총폴리페놀, 총플라보노이드, 전자공여능(EDA), ABTS radical 소거활성 및 ferric reducing antioxidant power (FRAP) 항목으로 측정하였다. 전체적으로 항산화활성은 S-1보다 S-2와 S-3에서 높은 함량을 나타났고, 가열시간이 길수록 증가했다. Sinigrin 함량은 대조군에서 검출되지 않았고, 시료간 유의적 차이가 없었다. 총아미노산은 가열시간이 길수록 볶은 샘플에서 glutamic acid의 함량이 높게 나타났고, aspartic acid, glycine, proline, alanine, arginine등이 높은 함량으로 검출되었다. 유리아미노산 함량은 감칠맛 계의 aspartic acid, glutamic acid함량이 높게 나타났다. 휘발성 성분들은 갓종자를 첨가한 육수는 2-propenyl- isothiocyanate (ITC) (C4H5NS), allyl thiocyanate (C4H5NS), n-butyl ITC (C5H9NS), 3-butenyl ITC (C5H7NS) 등이 검출되었다. 관능검사는 돌산갓 종자 첨가량과 가열시간이 길수록 높은 점수를 받아 전체적인 기호도가 증가하였고 시료간의 유의적인 차이를 나타냈다. 돌산갓 종자를 첨가한 육수의 품질적 특성을 토대로 돌산갓 종자를 첨가한 제품 개발을 위한 기초자료로 제시하고자 한다.