• 조명전기설비학회논문지
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• 제29권7호
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• pp.1-7
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• 2015

In this paper, we demonstrated a polarimetric fiber pressure sensor using a polarization-diversity-loop-based Sagnac interferometer(PDLSI) composed of polarization-maintaining fiber(PMF) and a fiber Bragg grating(FBG). In order to compare the pressure sensitivity for various kinds of PMF, three kinds of bow-tie PMF were employed as sensor heads. The maximum pressure sensitivity was measured as approximately -15.07nm/MPa, and an R2 value to represent sensor linearity was measured as ~0.992 at the sensor system using corresponding PMF over a pressure range of 0-0.3MPa. An FBG was utilized and located adjacent to the PMF segment for compensating temperature-induced errors in the measurement of pressure. The pressure sensitivity of the proposed sensor was improved by approximately four times compared with the previously reported pressure sensor based on polarization-maintaining photonic crystal fiber.

• 전자공학회논문지A
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• 제33A권7호
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• pp.1-14
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• 1996

Effects of the external optical feedback on the optical transmission characteristics were evaluated for 3 kinds of commercialized DFB-LD modules for 2.5Gbps optical communication systems. As a result, intensity noise induced by external optical feedback via generating the external cavity modes deteriorated the transmission performances of sthe DFB-LD modules as much as 1.5dB, 1.2dB, and 1.0dB for the maximum feedback ratio of -8.8dB which corresponds to the worst reflection along the fiber transmission line. Additional penalty of 0.5dB was occurrred when state of polarization of feedback light was adjusted. From the experiments evaluating the isolation ratio of the single polarization optical isolator, decrease of the polarization dependent isolation ratio as much as 10dB from that of specification and the effective isolation ratio as much as 20dB from that of specification was mjor cause of high sensitivity of DFB-LD modules to external feedback. It was suggested that polarization independent optical isolator or single polarization optical isolator with isolation ratio specification of more than 40dB is required for 2.5Gbps DFB-LD modules with complete suppression of external feedback effects.

• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 하계학술발표회 논문집
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• pp.275-276
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• 2007

체적형 홀로그래픽 메모리는 고용량의 저장밀도와 빠른 전송속도를 가지는 장점을 가지고있다. 더 높은 저장밀도를 얻기 위해 다양한 다중화 기법들이 연구되고 있다. 일정한 공간에 여러 개의 정보를 한꺼번에 저장할 수 있는 다중화 기법에는 각도에 따른 다중화, 기록 위치에 따른 다중화, 위상 변화에 따른 다중화를 비롯한 여러 가지 방법이 있다. 대부분의 다중화 기법들은 홀로그램을 저장할 때 순차적으로 기록하게 된다. 하지만 포토폴리머에 한번 정보가 저장되면 그 위에 다시 기록이 되지 않는다. 그래서 한번에 여러 개의 데이터를 저장하고 재생하는 시스템의 필요성이 요구된다. 본 논문에서는 이러한 점을 고려하여 빛의 편광성분을 이용해 다중화 하는 방법을 연구하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제27권5호
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• pp.437-448
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• 2023

Diabetic ulcer is usually seen in people with uncontrolled blood sugar. Reportedly, many factors such as impaired glucose metabolism, and macrovascular and microvascular diseases caused angiogenesis disorders and delayed the healing of diabetic ulcers, thus affecting the body's metabolism, nutrition, and immune function. This study aimed to explore the effect of paeonol on skin wound healing in diabetic rats and the related mechanism. A rat model of diabetic ulcer was established. High glucose-treated mouse skin fibroblasts were co-cultured with M1 or M2-polarized macrophages treated with or without paeonol. H&E and Masson staining were used to reveal inflammatory cell infiltration and collagen deposition, respectively. Immunohistochemistry visualized the expression of Ki67, CD31, and vascular endothelial growth factor (VEGF). Western blot was used to detect interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-4, IL-10, CD31, VEGFA, and collagen I/III. The expression of iNOS and arginase 1 was revealed by immunofluorescence staining. Paeonol treatment augmented collagen deposition and the expression of Ki67, CD31, VEGF, and macrophage M2 polarization markers (IL-4 and IL-10) and reduced wound area, inflammatory cell infiltration, and macrophage M1 polarization markers (IL-1β and TNF-α) in the ulcerated area. In vitro, paeonol treatment promoted M2-polarization and repressed M1-polarization in macrophages, thereby improving the repair of cell damage induced by high glucose. Paeonol accelerates the healing of diabetic ulcers by promoting M2 macrophage polarization and inhibiting M1 macrophage polarization.

• Journal of Advanced Marine Engineering and Technology
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• 제31권6호
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• pp.761-767
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• 2007

We have developed novel optical-fiber sensors based on strain-induced long-period fiber gratings for monitoring the deformation of a hull. They have no external pressure for sustaining the mechanical formed gratings. The pressure, which provides a force to form the periodic grating along the single mode fiber, was realized by the bonding strength of a photopolymer. To reduce the polarization dependency of the sensors caused by the asymmetry structure of gratings, a Faraday Rotator Mirror (FRM) was utilized in this experiment. We have realized the polarization-insensitive function of the proposed sensors. The change of an external strain are measured by an optical spectrum analyzer. When the external stain increases. the attenuation at the resonant wavelength decreases and the loss peak was slightly shifted to the shorter wavelength.

• Parasites, Hosts and Diseases
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• 제52권6호
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• pp.695-699
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• 2014

Chronic Opisthorchis viverrini-induced hepatobiliary disease is associated with significant leukocyte infiltration, including activated macrophages; however, the polarization of infiltrating macrophages remains to be fully characterized. In this study, we characterized macrophage polarization and phenotype in chronic O. viverrini-induced hepatobiliary disease in humans and hamsters using gene expression and histochemical analysis. Chronic O. viverrini infection and associated hepatobiliary diseases were associated with iron loaded M2-like macrophages in both humans and hamsters. This study provides suggestive evidence that iron loaded M2-like macrophages promote hepatobiliary disease in chronic O. viverrini infection.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2009년도 특별 심포지엄
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• pp.73-87
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• 2009

Geophysical survey for unconformity-type uranium deposit applied to this study area in Athabaska Basin, Canada were carried out airborne TEM and magnetic, resistivity-induced polarization (DC-IP), puser seismic reflection and well-logging method. The results of airborne survey interpreted the lithological boundary, geological structures, and conductors. Also, these results decided to main targets for ground DC-IP survey. The Low resistivity and the high chargeability slices of 3D modeling interpreted from DC-IP survey response for conductors related to hydrothermal alteration zones and fault-controlled graphitic zones occurring at the unconformity-type uranium deposit, and they confirmed by diamond drilling. Seismic results interpreted to lake bottom surface, alluvium layer and intra-sandstone faults. We suggest the resonable field data acquisition of DC-IP method on the land or the lake in Athabaska Basin.

• 자원환경지질
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• 제19권3호
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• pp.193-197
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• 1986

균질대지에서 시간영역 유도분극탐사를 실시할 때 생기는 전자기결합의 영향을 간단히 계산할 수 있는 해를 구하였다. 여기서 유도한 근사해는 시간영역의 전자기결합에 모델변수가 얼마 만큼영향을 미치는지를 쉽게 이해할 수 있으며, 또한 실제 상황에서 충분히 사용할 수 있는 정확도를 가지고 있다. 본논문에서는 쌓극자 및 Wenner 배치만을 다루웠지만, 이 근사해는 모든 전극배치에 대하여 유용하다.

• 자원환경지질
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• 제21권2호
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• pp.165-169
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• 1988

2차원 구조에 대한 음수의 분도분극 반응을 차분법을 이용한 2차원 모델링 기술로 검토하였다. 유도분극 변수로서는 섭동방법으로 효율적으로 계산이 가능한 주파수 효과를 사용하였다. 전도성이면서 분극성인 얇은 표토층은 가상단면도상에서 뚜렷한 음수의 유도분극 반응을 일으킨다. 이는 분극성 표토층하에 존재하는 저항성인 부극체에 의한 반응이 단지 비저항분포의 함수만으로 음폐되는 것을 뜻한다. 그러나, 분극성 표토층하의 저항성인 비 분극체는 음수의 반응으로 발견될 수 있다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.41-42
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• 2000

Photosensitive polyimides containing cinnamoyl and coumarin side groups were synthesized in a high molecular weight, giving a good quality of films. Nematic liquid-crystal (LC) molecules on the film were aligned along the direction with an angle of $97-99^{\circ}$ respect to the polarization of ultraviolet (UV) light. The LC alignment was induced mainly by the photoaligned polymer chains made by the first UV-exposure even though the film was treated by multiple exposures with changing the polarization of UV light. From these results, it is concluded that the LC alignment on the film is induced by the photodimerization rather than the trans-cis photoisomerization.