• 정보저장시스템학회논문집
• /
• 제3권4호
• /
• pp.173-177
• /
• 2007

A photo-reactive methacrylate monomer having triazine as a core component was examined for photochromic diffractive image formation. Photochromic photopolymer films as a recording media contained a monomer mixture of triazine difunctional metharylate (DT) and ethylene glycol phenyl ether acrylate, binder polymer, photo initiator, and a photochromic spiro-oxazine dye. The content of photochromic dye was changed to examine the effect of photochromophore on diffraction efficiency and real holographic image formation. Holographic recording was performed on the photopolymer film by the combination of reference and probe beam. The diffraction efficiency of the photopolymer film in real-time measurement reached a maximum of $\sim90%$ within 30s. It was highly dependent on the photochromophore contents. After holographic recording, the color of the recorded area was changed under UV light (365 nm) and reversibly bleached to original color upon exposure to a visible light source. Films containing only photochromophore without monomer mixture were not reactive under the recording beam (491nm). Diffractive image formation and mechanism of the holographic recording in the presence of photochromophore will be presented.

• 융합신호처리학회논문지
• /
• 제20권1호
• /
• pp.16-23
• /
• 2019

PM 2.5로 불리는 초미세먼지는 인간의 건강을 해치는 2.5 ㎛ 이하 직경의 입자크기를 갖는 공기 중의 미세먼지를 말하며, 미세먼지 집중도는 공기 질 정보로 사용할 수 있다. 사람은 일반적으로 90% 이상을 실내에서 거주하며 실내에 대한 공식적인 먼지 집중도 자료는 제공되지 않기 때문에, 본 연구는 실내의 관점에서 공기 질 측정에 초점을 두었다. 실내 먼지데이터 모니터링은 병원과 같은 환경에서 매우 중요할 뿐만 아니라 교실, 시멘트 공장, 컴퓨터 서버 룸, 석유화학 저장고 등의 장소에서도 유용하게 사용할 수 있다. 본 논문에서는 전자기파로부터 자유로운 실내 먼지 모니터링을 위해 맨체스터 코딩기법을 이용한 가시광 통신 시스템을 제안한다. 넓은 범위의 먼지 집중도를 포함한 중요한 실내 환경정보가 가시광 채널을 통해 전송된다. 강력한 주변광 및 저주파 잡음 제거를 위해 평균전압트레킹 기법을 사용한다. 입력광은 광다이오드에 의해 수신되고, 동시에 수신 마이크로콘트롤러에 의해 신호처리 한다. 사용자는 실시간으로 실내 공기 질 정보를 모니터링 할 수 있으며, 공기 질 정보에 따라 미리 적합한 대처를 할 수 있다.

• 동아시아식생활학회지
• /
• 제23권5호
• /
• pp.546-560
• /
• 2013

In this study, a natural fermentation starter formulation was developed for manufacturing Korean bread products by substituting baker's yeast with naturally fermented blueberry starters. As the incubation time of the blueberry extracts increased, the pH and total titratable acidity increased. The sweetness (brix%) of blueberry extracts containing various amounts of sugar were higher than the other sample. The result of alcoholicity for naturally fermented blueberry extracts, the fermented blueberry extract containing 20% sugar was highest. Lactic acid bacteria counts increased until the 4th day; however, it decreased from the 5th day, and viable yeast counts increased consistently until the 5th day. The volume for naturally fermented blueberry extracts increased as the incubation time increased. As the fermentation time of blueberry starters increased, the pH of bread dough decreased. The RVA analysis conveyed that wheat flour retrogradation was retarded by increasing the blueberry starter content. The weight of pan breads containing blueberry starters were higher than that of the control, while the volume, specific volume and baking loss rate were lower than those of the control. The moisture content of pan breads containing blueberry starter decreased as storage time increased. In analyzing the visible mold colony during 7 days of storage at $28^{\circ}C$, mold growth in pan breads containing the blueberry starter was retarded. The hardness of breads containing blueberry starters were significantly increased as storage time increased. The breads containing 50% naturally fermented blueberry starter have acceptable sensory properties. In conclusion, these results indicated that 50% of natural fermentation blueberry starter could be very useful as a substitute for yeast when making naturally fermented bread.

• 한국식품영양과학회지
• /
• 제25권3호
• /
• pp.441-452
• /
• 1996

The effects of chlorophyll, tocopherols($\alpha$-tocopherol, ${\gamma}$-tocopherol and $\delta$-tocopherol), carotenoids ($\beta$-carotene and lutein), light sources, light intensities and strage temperatures on the photooxidative stability of soymilk were studied by measuring TBA value and depleted headspace oxygen(DHO) of soymilk. The samples were stored in the light storage box for 6 days and evaluated for the photooxidative stabilities. As the concentrations of chlorophyll increased, TBA value and DHO of the sample increased significantly(p<0.05), indicating chlorophyll acting as a photosensitizer. However, as the concentrations of tocopherols ($\alpha$-tocopherol, ${\gamma}$-tocopherol and $\delta$-tocopherol) and carotenoids ($\beta$-carotene and lutein) increased, TBA values and DHO of the samples decreased significantly(p<0.05). The light screening effects of carotenoids on DHO in the samples were not significantly different from the control at p>0.05. Therefore, there was no light screening effects of carotenoids on the oxidative stability of soymilk. The results indicate that tocopherols and carotenoids reduce the photooxidative stability of soymilk. $\delta$-Tocopherol was the most effective in photosensitized oxidation followed by ${\gamma}$-and $\alpha$-tocopherols in the order of increasing stability. $\beta$-Carotene was significantly(p<0.05) more effective than lutein in minimizing the chlorophyll-sensitized photooxidation of soymilk. Visible light was more effective than UV light in decreasing the photooxidative stability of soymilk. Therefore, photooxidation of soymilk containing chlorophyll is mainly due to photosensitized oxidation rather than photolysis reaction. As the intensities of fluorescence light increased, TBA values and DHO of the samples increased significantly at P<0.05. However, as the storage temperatures increased, TBA values and DHO of soymilk did not change significantly at p>0.05.

• 보존과학회지
• /
• 제36권4호
• /
• pp.255-263
• /
• 2020

Paulownia coreana has various advantages as a convenient workability, aesthetic outlook, beautiful patterns, low weight and high strength, and its permeability. P. coreana has been widely used for storage but there are no empirical researches proving its functionality in a field of conservation science until now. In this study, the seasonal and daily temperature and relative humidity control, and microbe and insect repellent activity were evaluated under the controlled and uncontrolled circumstances from 2015 to 2016. The results showed to be mainly excellent in relative humidity control and the buffering effect was good to adjust the average daily relative humidity range from the outside. With respect to the antimicrobial properties of P. coreana, we observed that its water-soluble extract produced visible zones of inhibition against five bacteria. However, it was difficult to predict the antimicrobial and/or insecticidal properties.

• 한국식품조리과학회지
• /
• 제31권3호
• /
• pp.264-279
• /
• 2015

The principal objective of this study was to evaluate the effects of the addition of sourdough to various grain flours in bread, specifically, in regards to the physicochemical characteristics of bread dough, sensory evaluation, and bread storage. As the incubation time of sourdough increased, the total titratable acidity increased. Viable yeast counts of sourdough increased consistently until the third day, while lactic acid bacteria counts increased until the second day. The weight of breads containing sourdough made with rye flour, strong flour, and Korean wheat flour were higher than that of the control. However, the height, volume, and specific volume of control were higher than those of the groups with sourdough made with various grain flours. The pH of breads containing sourdough was lower than that of the control, while the total titratable acidity and moisture content were higher than those of the control. In analyzing the visible mold colony during the five days of storage at $30^{\circ}C$, mold growth in breads containing sourdough made of Korean wheat flour, barely flour, and rye flour was retarded. In the color measurement, the L values of the control and bread containing sourdough made with barley flour were higher than that of the other groups after five days. The a value of bread containing sourdough made of rye flour was higher, and the b values of breads containing sourdough made of Korean wheat flour, barley flour and rye flour were higher than those of the other groups after five days. The hardness of breads containing sourdough increased as storage time increased, where as breads containing sourdough made of Korean wheat flour, Korean whole wheat flour, and rye flour revealed no significant differences with control group. Sensory evaluation scores in terms of after swallowing, taste, and overall preference of bread containing sourdough made of Korean wheat flour was higher than those of the control group.

• 한국염색가공학회지
• /
• 제21권4호
• /
• pp.23-32
• /
• 2009

The objective of this study is to investigate the efficacy of leaf powder colorants as substitutes for traditional indigo dyeing. Leaf powder colorants were prepared by hot air($50^{\circ}C$) and room temperanrre($25^{\circ}C$) drying methods from fresh leaves. The presence of indigo in the leaf powder colorants was confirmed by UV/Visible absorption spectra. All the powder colorants showed broad absorption at 602 nm as same as synthetic indigo. Dyeing was done by reduction method with sodium hydrosulfite and sodium hydroxide. Leaf powder colorants produced blue color on silk fabrics, showing similar color to the one dyed traditionally with fresh juice extract. The powder colorants prepared at room temperature drying were more stable for long term storage than that prepared by hot air drying. Thus, the powder colorants prepared by room temperature drying was reduced and dyed in one-step process without sodium hydroxide in the dyebath for further investigate dyeing properties. K/S value of the fabric dyed without sodium hydroxide was much higher than one dyed with sodium hydroxide. Regardless of the addition of sodium hydroxide, rubbing fastness was fairly good showing above 4 rating. Fastness to dry cleaning and light of the fabrics dyed without sodium hydroxide were mote higher than that dyed in alkaline condition.

• 동아시아식생활학회지
• /
• 제26권3호
• /
• pp.260-270
• /
• 2016

간장 첨가량을 달리한 양하피클을 제조하여 90일 저장기간 동안 pH, 당도, 염도, 수분함량, 색도, 환원당, 경도, 총균수 등의 품질평가와 관능평가를 비교하였다. 간장 첨가량이 증가할수록 pH, 염도, 당도가 높아졌다(p<0.001). 양하 피클의 수분 함량은 간장량이 증가할수록 저장기간이 길어질수록 감소하였다. 양하 피클의 경도는 제조 0일차에는 $202.6{\sim}235.9g/cm^2$이고, 90일차에는 $352.2{\sim}368.3g/cm^2$로 저장기간이 경과함에 따라 증가하다가 감소하는 결과를 보였고, 간장함량이 증가될수록 높았다. 명도는 간장 첨가량이 증가할수록 낮았고, 적색도는 J1이 높았으며, 황색도는 저장기간 동안 J1을 제외하고 증가하였다. 양하 피클의 관능적 특성 결과, 양하 피클은 매운맛을 제외하고 유의적인 결과 값을 나타냈으며, 맛, 향, 전반적인 기호도에서 간장 10%를 첨가한 J2가 유의적으로 높은 선호도를 나타냈다. 양하 피클의 외관과 색은 간장의 첨가량이 증가할수록 기호도가 낮아졌다. 따라서 양하를 이용한 피클은 오랫동안 저장하여도 우수한 품질을 유지할 수 있어 피클로서 제조가 가능할 것으로 생각된다.

• 한국식품조리과학회지
• /
• 제28권2호
• /
• pp.159-165
• /
• 2012

본 연구에서는 땅두릅잎을 이용하여 양념을 달리한 LA(간장), LB(간장+고춧가루), LC(간장+고춧가루+젓갈)의 잎김치를 제조하여 저장기간에 따른 총 비타민 C, 환원당, 식이섬유, 총 클로로필, 총 수용성 고형분 함량을 측정하였다. 실험결과, 땅두릅 잎김치의 화학적 특성에서 총 비타민 C는 저장기간이 경과함에 따라 모든 실험군이 감소하였으며 비교적 높은 잔존율을 나타내었다. 환원당의 경우 저장 초기부터 완만하게 감소하다가 저장 5개월에는 급격히 감소하여 이후부터 저장 6개월까지 다소 완만하게 감소하는 경향이었다. 식이섬유는 전반적으로 저장기간이 길어짐에 따라 수용성 식이섬유는 증가하고 불용성 식이섬유는 감소하는 경향을 보였으며 총 식이섬유는 다소 증가하거나 일정 수준을 유지하였다. 총 클로로필은 저장 1개월에는 다소 감소하다가 저장 3개월에 증가했다가 다시 감소하는 경향을 나타내었다. 처리구 LB가 가장 높은 클로로필 함량을 나타내었으며 대조구인 LA가 가장 낮은 잔존율를 보였다. 총 수용성 고형분 함량은 저장 초기 LA, LB, LC가 각각 10.3, 10.1, 10.4%이었으며 저장 1개월에는 11.7, 11.3, 12.1%로 다소 증가하였고 저장 3개월에는 12.8, 12.2, 13.0%이었으나 저장 6개월에는 12.0, 11.0, 12.5%로 총 수용성 함량이 다시 감소하는 경향을 나타내었다. 따라서 땅두릅 잎김치는 양념 및 가공방법을 더 다양화한다면 땅두릅잎은 식품의 적용을 증대시켜 아울러 소비를 증대 시킬 수 있을 것으로 기대된다.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
• /
• pp.75-83
• /
• 2003

Diode laser absorption system is advantageous of their non-invasive nature, fast response time, high sensitivity and real-time measurement capability. Furthermore, recent advances in room-temperature, near-IR and visible diode laser sources for telecommunication, optical data storage applications are enabling combustion diagnostics system based on diode laser absorption spectroscopy. So, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor system are now appearing for a variety of applications. The objective of this research is to take advantage of distributed feed-back diode laser and develope new gas sensing system. It experimentally found out that the wavelength, power characteristics as a function of injection current and temperature. In addition to direct absorption and wavelength modulation spectroscopy have been demonstrated in these experiments and have a bright prospect to this diode laser system.