• Macromolecular Research
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• 제10권5호
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• pp.278-281
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• 2002

We investigated the photoluminescence (PL) characteristics of a highly soluble, fullerene-containing copolymer in both solution and film states. In solution state, the copolymer showed different PL characteristics depending on the aromaticity of the solvent. The PL from polystyrene segments of the copolymer was strongly quenched in an aromatic solvent, while the PL from fullerene remained unchanged. However, the films cast from an aromatic and a nonaromatic solvent demonstrated very similar PL characteristics, implying that the chain alignment or orientation and packing in the films occur in a similar way irrespective of the solvent.

• 한국진공학회지
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• 제18권5호
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• pp.365-371
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• 2009

크기가 다른 양자점 (chirped 양자점) 구조에 대하여 전기발광 (Electroluminescence, EL) 특성과 광발광 (Photoluminescence, PL) 특성을 측정하고 비교 분석하였다. PL 특성에서는 양자점의 기저준위에 의한 피이크가 우세하게 나타난 반면, EL 특성에서는 여기준위에 의한 특성이 우세하게 나타났다. 이와 같은 특성비교로부터 기저준위도 EL 특성에 영향을 미칠 수 있도록 chirped 양자점 구조를 설계하면 파장대역폭이 더욱 넓은 고휘도 발광소자 개발이 가능할 것임을 제안하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.27-30
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• 1997

We investigated the electro-optical characteristics of amorphous (a) - twisted nematic (TN) - liquid crystal display (LCD) on polyimide (Pl) films with different polarity. It was found that the threshold voltage of a-TN-LCD is decreased with increasing the polarity of the Pl film. We considered that the threshold voltage in a-TN-LCD is affected to the surface anchoring strength with polarity of the Pl films. Also, we observed the response time of a-TN-LCD on medium polarity of the Pl film is fast compared to high polarity of the Pl film. Finally, we obtained that the viewing angle of a-TN-LCD are almost same on different polarity of the PI films.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.22-22
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• 2003

Studies on the optical properties related to the built-in internal field and the carrier localization present in various GaN-based structures are essential not only for the physical interest but in designing practical visible and ultraviolet light emitting device applications with better performance and quantum efficiency. We report on the optical characteristics of various dimensional GaN-based structures such as (i) GaN self-assembled quantum dots grown in Stranski-Krastanov mode (OD), vertically-aligned GaN nanorods (1D), graded-In-content InGaN quantum wells (2D), laterally-overgrown GaN pyramids (3D), and GaN epilayers grown on various substrates. We used a wide variety of optical techniques, such as photoluminescence (PL), PL excitation, micro-PL, cathodoluminescence, optically-pumped stimulated emission, and time-resolved PL spectroscopy. An overview and comparison of the optical characteristics of the above GaN-based structures will be given.

• Current Optics and Photonics
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• 제3권2호
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• pp.164-171
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• 2019

Photoluminescence (PL) properties of GaN-based light-emitting diodes (LEDs) were analyzed to study the effects of carrier leakage on the luminescence properties at room temperature. The electrical leakage and PL properties were compared for LEDs showing leakages at forward bias and an LED with an intentional leakage path formed by connecting a parallel resistance of various values. The leakages at the forward bias, which could be observed from the current-voltage characteristics, resulted in an increase in the excitation laser power density for the maximum PL efficiency (ratio of PL intensity to excitation power) as well as a reduction in the PL intensity. The effect of carrier leakages on PL properties was similar to the change in PL properties owing to a reduction of the photovoltage by a reverse current since the direction of the carrier movement under photoexcitation is identical to that of the reverse current. Valid relations between PL properties and electrical properties were observed as the PL properties deteriorated with an increase in the carrier leakage. The results imply that the PL properties of LED chips can be an indicator of the electrical properties of LEDs.

• 산업경영시스템학회지
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• 제40권2호
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• pp.22-30
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• 2017

PL (Product Liability) refers to the legal responsibility of a manufacturer or seller for bodily injuries or property losses caused by product defects. Therefore, it is important for companies to construct a product liability response system that strategically manage and effectively adapt to product liability. A PL response system refers to companywide operations of PL prevention (PLP) measures, product safety (PS) measures, and PL defense (PLD) measures appropriate for a company's scale and environment. To establish an enterprise product liability response system, each essential component of corporations should be systematically operated and maintained considering the scale and characteristics of the corporations. Essential components of PL response system is Strategy, Organization, Training, Technology, Investment, and Awareness. Role of essential components is that companies need specific strategies to secure product safety and protect customers from product defects, and appropriate organizations must be composed for effective operation of such strategies. The objective of this paper seeks to examine the relationships among the essential components of the product liability response system and PL performance. PL performance consists of positive performance and negative performance. In particular, positive performance include increased efforts in product or process innovation such as strengthening research and development (R&D) to produce safer products without defects. In order to carry out this research we obtained 98 questionnaire of manufacturing company. A summary of the analyses is as follows: First, the awareness and technology among essential components affect significantly to the positive performance. Second, the awareness and strategy among essential components negative affect to the negative performance.

• 한국식품과학회지
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• 제37권2호
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• pp.247-254
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• 2005

유색 감자의 일반적인 성분과 무기질, 색도, anthocyanin의 함량 그리고 생리활성에 대하여 검토하였다. 유색감자 계통별로 횡단면의 색소형성 정도에 따라 A. B, C, D Type둥 4가지 형태로 분류되었다. 일반성분은 수분 함량이 75.7-84.3%, 단백질이 1.3-2.7%, 조섬유 함량이 0.2-0.7% 수준으로 계통에 따라 약간 차이를 보였다. 유색감자내 무기질은 괴경 100g당 2-3mg의 칼슘과 1-2mg의 나트륨, 350-510mg의 칼륨을 함유한 것으로 나타났으며, 무기질 함량은 계통별로 차이를 나타냈다. 색차계를 이용하여 유색감자 횡단면의 색도를 측정한 결과, 색차의 크기는 PL-31>PL-6>PL-28>PL-12>PL-4>PL-17 등의 순으로 나타났으며, 관능검사에 의한 유색강도를 시험한 결과 PL-14>PL-31>PL-28>PL-3>PL-17>PL-6 등으로 나타나서 유사한 경향을 보였다. 총 anthocyanin 색소 함량은 계통별로 큰 차이를 나타내었으며 100g 당 3.3-29.0mg 수준이었으며, PL-28>PL-31>PL-14>PL-12>PL-5 >PL-3의 순으로 높았다. 선발된 품종간 항산화력 비교 실험 결과, PL-6을 제외한 PL-28, PL-31 그리고 자심은 대조구인 ${\alpha}$-tocopherol보다 항산화력 활성이 약간 높았으며, BHA의 항산화력에는 미치지 못하는 것으로 확인되었다. 그리고 Gram(+) 3종과 Gram(-) 3종을 이용한 항균활성을 측정한 결과, 4품종 모두 Gram(+)와 Gram(-) 모두 항균력을 나타내었다. Gram(+)에서는 B. subtilis에 가장 높은 항균활성을 나타내었고, Gram(-)에서는 E. coli에서 항균활성을 나타내는 것으로 확인되었다.

• 한국축산식품학회지
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• 제25권1호
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• pp.52-59
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• 2005

본 실험은 저지방 소시지인 대조구와 젖산나트륨 및 젖산칼륨의 첨가 수준에 따라 처리구를 대조구(CTL, Low-fat sausages control), TRT1(Sodium lactate, SL 3.3%), TRT2(SL 2.2% + Potassium lactate, PL 1.1%), TRT3(SL 1.1% + PL 2.2%), TRT4(PL 3.3%)로 나누어 제조하여 냉장저장기간 동안 품질 및 저장성을 조사하기 위하여 실시하였다. 저지방 소시지의 일반성분에서 수분은 73.9∼75.4%, 지방 l∼2%, 단백질은 15.5∼15.9%이였고, pH는 5.8∼6.5범위였으며 젖산나트륨이나 젖산칼륨의 첨가에 따른 냉장 저장 중의 뚜렷한 변화는 보이지 않았다(p>0.05). 냉장 저장 중 유리수분은 전체적으로 22.9∼33.0%범위였으며 저장기간이 증가할수록 증가하는 경향을 보였다(p<0.05). 그러나 진공감량은 2.7∼5.3 범위였고 냉장 저장 중에 차이를 보이지 않았다. 색도는 젖산나트륨이나 젖산칼륨의 첨가에 따른 냉장저장 중의 차이가 거의 나타나지 않음으로써 소시지의 색도에 거의 영향을 끼치지 않는 것으로 나타났다(p<0.05). 조직감의 경우, 대조구는 모든 항목에서, TRT1은 부서짐성과 경도에서, TRT3은 응집력에서 저장기간이 경과할수록 증가하는 경향을 나타내었다. 하지만 젖산나트륨과 젖산칼륨의 첨가는 조직감에 뚜렷한 영향을 미치지 않았다. 미생물의 변화의 경우 저장 4주후부터 10주까지 대조구보다 처리구가 크게 낮아져 유의차가 있었다(p<0.05). 이상의 결과를 종합하면 저지방 소시지에 젖산나트륨 및 젖산칼륨의 첨가는 Listeria monocytogenes에 대하여 저장 중에 품질에 영향을 주지 않으며 우수한 항균효과를 가지고 있었다.

• 유통과학연구
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• 제18권10호
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• pp.121-130
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• 2020

Purpose: In this study we investigate the determinants of private label (PL) purchase intention in South Korea. Private labels are becoming more and more popular in America and European countries. However, there are not enough studies focusing on PL within the South Korean market. Therefore, the present study has been written in order to understand more about consumers' purchase intention of store brand in the South Korean market. Many characteristics and aspects of consumers and brand's behavior have been reviewed in order to bring relevant results. Research design, data and methodology: Data was collected using a quantitative survey of Korea retail store's consumer. We analyzed using multiple regression method to test the hypothesis. We analyzed how and why do consumers have a strong intention to purchase the PL. Results: a) Trust towards retailer influences the PL purchase intention of customers; b) brand awareness has an impact on the PL purchase intention of customers; c) perceived quality has an impact on the PL purchase intention; d) Price-quality relationship influences on the PL purchase intention. However, there is no direct effect of some of the factors of determinant. Conclusion: For private label products in the Korean market, trust in sellers and brand awareness influences the purchase of PL products.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.122-122
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• 2010

ZnO is a widely investigated material for the blue and ultraviolet solid-state emitters and detectors. It has been promoted due to a wide-band gap semiconductor which has large exciton binding energy of 60 meV, chemical stability and low radiation damage. However, there are many problems to be solved for the growth of p-type ZnO for practical device applications. Many researchers have made an efforts to achieve p-type conductivity using group-V element of N, P, As, and Sb. In this letter, we have studied the optical characteristics of the antimony-doped ZnO (ZnO:Sb) thin films by means of photoluminescence (PL), PL excitation, temperature-dependent PL, and time-resolved PL techniques. We observed donor-to-acceptor-pair transition at about 3.24 eV with its phonon replicas with a periodic spacing of about 72 meV in the PL spectra of antimony-doped ZnO (ZnO:Sb) thin films at 12 K. We also investigate thermal activation energy and carrier recombination lifetime for the samples. Our result reflects that the antimony doping can generate shallow acceptor states, leading to a good p-type conductivity in ZnO.