• 한국초등과학교육학회지:초등과학교육
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• 제27권3호
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• pp.244-251
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• 2008

One of the problems with testing for the presence of $CO_2$ is that the results are not visible. In order to over-come this weak point, a new testing method was developed with BTB indicator equipment, that made the gas visible. After that, the experiment was performed and tested the effects of the new visible equipment. The visible equipment could be adapted to regular class use successfully. Also, it was effective in that it reduced waste of gas, minimized danger potential through use of $CO_2$ canisters and candle-sticks, and also increased knowledge about indicators. The new experimental method and equipment affected the students' interest. It is possible that the students' positive participation was due to their interest in the new apparatus and application of the visual senses. The new system was tested fer its effects on teaching content and helping to produce sustained memory of the content. There were no significant differences between the groups in terms of content learning on initial content memory. However, when students in both groups were tested 4 months later, the visual experiment group sustained memory performance, while the other group showed a significant decrease. Generally, boys score higher than girls in terms of interest and participation in experimental activities. In this case, however, there were no difference between groups. It may have been due to introduction of new equipment and different methods from the textbooks. So, this could increase participation in science using various experiments.

• 생물환경조절학회지
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• 제9권2호
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• pp.94-100
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• 2000

자극 종류(광질, 촛불, 바람, 수온)에 따른 식물의 엽표면 전위 포텐셜의 변화가 조사되었다. 광자극시 광질 및 점.멸간격(5초, 15초, 30초)에 따른 전위포텐셜의 변화는 다르게 나타났으며, 동일한 자극일지라도 아침, 점심, 저녁시간에 따라 그 반응이 달랐다. 또한, 촛불대기, 바람, 5$^{\circ}C$의 저온수 분무 등의 자극도 엽표면 전위포텐셜의 변화를 발생시켰으며, 식물에 따라 반응 패턴이 서로 다르게 나타났다. 결국 같은 자극일지라도 식물종에 따라 엽표면 전위포텐셜의 변화가 다르게 나타났으며, 동일한 식물일지라도 자극의 종류에 따라 서로 다른 반응패턴을 보였다. 한편, 전위포텐셜의 주파수 분석에 따르면, 대부분의 자극에 대해서 10Hz 대역이 다른 주파수 대역보다 높은 값을 나타내었다.

• 천문학회보
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• 제46권1호
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• pp.47.4-48
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• 2021

Gravitationally lensed Type Ia supernovae may be the next frontier in cosmic probes, able to deliver independent constraints on dark energy, spatial curvature, and the Hubble constant. Measurements of time delays between the multiple images become more incisive due to the standardized candle nature of the source, monitoring for months rather than years, and partial immunity to microlensing. While currently extremely rare, hundreds of such systems should be detected by upcoming time-domain surveys. Others will have the images spatially unresolved, with the observed lightcurve a superposition of time delayed image fluxes. We investigate whether unresolved images can be recognized as lensed sources given only lightcurve information and whether time delays can be extracted robustly. We develop a method that we show can identify these systems for the case of lensed Type Ia supernovae with two images and time delays exceeding ten days. When tested on such an ensemble the method achieves a false positive rate of ≲5%, and measures the time delays with the completeness of ≳93% and with a bias of ≲0.5% for time delay ≳10 days. Since the method does not assume a template of any particular type of SN, the method has the potential to work on other types of lensed SNe systems and possibly on other transients.

• 문화기술의 융합
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• 제1권3호
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• pp.23-30
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• 2015

향을 이용한 아로마테라피는 고대부터 전 세계적으로 종교적 또는 질병치유 목적으로 사용되어 왔다. 최근에는 많은 사람들이 피부관리, 염증치료 등 치유 목적이외에 정신건강을 위하여 아로마테라피를 사용하고 있다. 많은 아로마테라피 디퓨저들은 다양한 형태와 소재들이 활용되고 있지만 대부분의 제품은 자연적으로 공기 중에 향을 휘산시키거나 양초 등의 열을 이용한 훈증 방식을 채택하고 있다. 우리나라 분청사기는 전통적, 문화적으로 매우 중요한 위치를 차지하고 있다. 우리는 분청 사기의 디자인, 형태, 문양 등을 발전시키고 새로운 제품에 접목시켜 현대사회의 소비자 요구에 부응하여야 한다. 본 연구의 목적은 분청사기와 아로마 디퓨저를 결합하고 소비자가 제품에 대하여 가지고 있는 감성이미지를 추출하여 소비자를 만족시킬 수 있는 아로마 디퓨저를 개발하는 것이다. 그리고 이를 통하여 전통의 긍정적 이미지와 문화 인프라를 구축하고 전통 도자기를 고부가가치 산업으로 연계하고자 한다.

• Parasites, Hosts and Diseases
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• 제55권4호
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• pp.409-416
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• 2017

The high prevalence of pediculosis capitis, commonly known as head lice (Pediculus humanus capitis) infestation, has led to the preparation of a community-based pediculicidal ointment, which is made of common household items and the extract of Tinospora crispa stem. The present study aimed to evaluate the safety, efficacy, and physicochemical characteristics of the T. crispa pediculicidal ointment. The physicochemical properties of the ointment were characterized, and safety was determined using acute dermal irritation test (OECD 404), while the efficacy was assessed using an in vitro pediculicidal assay. Furthermore, the chemical compounds present in T. crispa were identified using liquid-liquid extraction followed by ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric (UPLC-qTOF/MS) analysis. The community-based ointment formulation was light yellow in color, homogeneous, smooth, with distinct aromatic odor and pH of $6.92{\pm}0.09$. It has spreadability value of $15.04{\pm}0.98g{\cdot}cm/sec$ and has thixotropic behavior. It was also found to be non-irritant, with a primary irritation index value of 0.15. Moreover, it was comparable to the pediculicidal activity of the positive control $Kwell^{(R)}$, a commercially available 1% permethrin shampoo (P>0.05), and was significantly different to the activity of the negative control ointment, a mixture of palm oil and candle wax (P<0.05). These findings suggested that the community-based T. crispa pediculicidal ointment is safe and effective, having acceptable physicochemical characteristics. Its activity can be attributed to the presence of compounds moupinamide and physalin I.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2010년도 춘계학술대회
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• pp.145-147
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• 2010

해안 또는 항만에 설치되는 항로표지 시설에 3색 LED를 적용하여 식별을 용이하게 하는 시각적인 감성식별 조명에 대한 연구로 항만 양측의 홍등 및 녹등에 의하여 입구를 확실하게 표시하고, GPS에 의한 시각동기와 타이머를 통하여 항만 유도등을 좌우동시 동기 및 일렬순차 동기시키는 콘트롤러를 구현하였다. LED에 의한 등대 구조물을 다양한 색상으로 표현하고 또한 높이에 따른 층별 색상으로 조화시키는 감성적 조명으로 야간에 항만의 수많은 조명과 구별되어 항해사들의 표지식별에 대한 혼란을 예방하고, 야간항만의 경관을 미화시키는 기대효과가 있다. 선박의 항만진입을 돕는 유도등의 동기 및 순차점멸 그리고 항만안전 메시지를 전달하는 CW 발광에 대한 기능을 부가하였고, 동명기를 고휘도 LED로 대체하여 전력소비를 크게 감소시킨다.

• 천문학회보
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• 제38권2호
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• pp.45.1-45.1
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• 2013

Type Ia supernovae (SNe Ia) are a powerful tool to investigate the expansion history of the universe, because their peak luminosity is as bright as a galaxy and is known as an excellent standard candle. Since the discovery of the acceleration of the universe based on the observations of SNe Ia, higher than ever accuracy of their peak luminosity is needed to investigate various problems in cosmology. We started a project to improve the accuracy of the calibration of the peak luminosity of SNe Ia by measuring accurate distances to nearby resolved galaxies that host SNe Ia. We derive accurate distances to the SN Ia host galaxies using the method to measure the luminosity of the tip of the red giant branch (TRGB). In this study we present the results for M66 and M96 in the Leo I Group which are nearby spiral galaxies hosting SN 1989B and SN 1998bu, respectively. We obtain VI photometry of resolved stars in these galaxies from F555W and F814W images in the Hubble Space Telescope archive. We derive the distances to these galaxies from the luminosity of the TRGB. With these results we derive absolute maximum magnitudes of two SNe (SN 1989B in M66 and SN 1998bu in M96). We derive a value of the Hubble constant from the optical magnitudes of these SNe Ia and SN 2011fe in M101 based on our TRGB analysis. This value is similar to the values derived from recent estimates from WMAP9 and Planck results, but smaller than other recent determinations based on Cepheid calibration for SNe Ia luminosity.

• 한국환경보건학회지
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• 제44권3호
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• pp.275-282
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• 2018

Objective: Since certain chemicals are widely applied in a variety of consumer products, exposure via simultaneous use of multiple consumer products can put human health at risk. For this reason, use patterns of consumer products are an important factor inhuman health risk assessment. The aim of this study is to investigate co-use patterns of air-fresheners and deodorizers in Korea in order to estimate potential cumulative exposure. Methods: To collect the information on use patterns of air-fresheners and deodorizers, ten air-fresheners and 14 deodorizers were selected. A total of 3,000 participants were recruited and asked through on line questionnaires whether they had simultaneously used the selected air-fresheners and deodorant products in their daily lives. Results: Among the 3,000 participants, 45.6% had used more than two air fresheners and 46.3% used more than two deodorizers. The most common types of air fresheners used concurrently include liquid and candle types for indoor environments, while those of deodorizers were fabric trigger sprays and refrigerator gels. In addition, 73.7% used more than two products without product categories. Fabric trigger sprays were contained in all of the high-ranking product combinations. Conclusions: This study showed that many consumers concurrently used air-fresheners and deodorizers in their daily routines. For accurate exposure assessment, co-use patterns of consumer products should be further investigated.

• 한국환경보건학회지
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• 제2권1호
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• pp.37-48
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• 1975

Air pollutants were measured to get useful data in preventing and controlling the pollution at industrial and semi-industrial, commercial, cross-road and residential areas by season in Busan from September 1973 to June 1974. Teated were dustfalls(ton/$km^2$/month)by Deposit Gauge method, sulfuric anhydride(mg $SO_3/day/100cm^2 PbO_2$) by Lead Peroxide candle method. The relations between pollution and metherologlcal factors and source of pollution were discussed, The findings are as follows: 1. The mean value of dustfalls was 24.8 tons rangi~ng from 12.5 tons to 44.5 tons. The highest amount of dustfalls of 29.0 tons was measured in crossroad areas while the 1oeest of 22.7 tons in commercial areas, and Winter the highest of 27.7 tons while in Spring the lowest of 21.2 tons. 2. The mean value of water soluble substances was 31.7 per cent, and seasonal variation of pH was shown as 4.20 in Autumn, 3.85 in Summer and 2.76 in Winter. 3. The mean value of sulfuric anhydride was 1.54mg ranging from 0.197mg to 4.162 mg. The highest concentration of sulfuric anhydride of 2.03mg was detected in cross-road areas while thelowest of 1.23mg in residential areas, and Summer the highest of 2.18mg while in Spring the lowest of 1.09mg(0. 92mg in Nov. 1973) 4. Dustfalls are more with the decreased of relative humidity and precipitation while concentrat:on of sulfuric anhydrides are more with the increased of relative humidity. 5. There is a probability of occuring chronic symptoms(respiratory and others) as the dustfalls with 24.8 tons and sulfuric anhydride with 1.54mg in Busan. According to this, it is the time to discuss monitoring system and systematic preventing methods.

• 대한수의학회지
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• 제33권1호
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• pp.93-99
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• 1993

This study was conducted to investigate the cause of a new duck disease occured in southern part of Korea. A meat type duck farm located in Kangjin, Chonnam Province had experienced outbreaks of septicemic disease at around 20 days of age in nearly every batch of ducklings from early spring to early summer in 1989. Main symptoms of the birds were eye and nasal discharge, depression, inappetence, diarrhea and nervous signs such as tremor and ataxia. Some birds died suddenly without any signs. Mortality reached from 20% to 80% in severe cases. The autopsy findings of the affected ducklings revealed consistantly severe airsacculitis, fibropericarditis, perihepatitis and occasionaly enteritis and distended ureter with urate deposit. A rod shaped gram-negative bacterium was isolated purely from brain and liver of the diseased ducks by culturing the specimens on blood agar for 48 hours in candle jar. The isolate neither produced hemolysis nor grew on MacConKey Agar. It formed colony relatively slowly being recognizable at least 36 hours after culturing, reaching colony size of about 1mm in diameter at 48 hours culture. The colony looked iridescent under oblique light and had muddy odor. The isolate did not ferment carbohydrates tested but produced gelatinase, hippuricase and oxidase which were considered as characteristics of P anatipestifer. The isolate induced similar signs and lesions when infected experimentally into ducks of 3 to 38 days age via intraperitoneum or intratrachea. However it did not produce any clinical signs wen inoculated via intranasal route. It produced only mild signs in chicken just injected with a very large dose. The bacteria did not produce any signas or lesions in mice. It was concluded through biochemical and physiological tests and animal inoculation tests that the new disease was caused by P anatipestifer.