• 대한전자공학회논문지SP
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• 제41권2호
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• pp.99-108
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• 2004

5.1채널 스피커 시스템을 이용하여 음향을 재현 시 나타나는 현상인 크로스토크를 제거하여 청취자에게 보다 입체적인 음을 재현하는 방법에 관한 것이다. 본 논문에서는 자유음장 모델에 기초하여 5.1채널 스피커 시스템의 보상함수를 해석, 이를 심리음향에 기초한 바크 스케일(bark scale) 등가 보상 밴드패스 필터에 적용하여 주파수 제한적인 음질 보상을 실시하였다. 정면 채널과 서라운드 채널의 음원을 제작하여 기존의 2채널 및 5.1 시스템에서 제시하는 음원과 비교하여 객관적인 음질평가 및 청취자를 대상으로 한 주관 평가를 실시하였다. 제안된 방법에 따라 측정한 결과에 따르면 ±30。의 정면 스피커를 배치한 돌비 표준 스피커 배치에서 38㏈ 이상의 분리도를 얻었으며 확산감에 대해 전문가를 대상으로 한 주관 평가는 5점 평가를 기준으로 0.4점이 향상되었다.

• 정보처리학회논문지B
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• 제11B권3호
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• pp.345-352
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• 2004

본 논문에서는 자유음장 모델을 기초로 5.1채널 스피커 시스템의 보상함수를 해석하고, 이를 심리음향에 기초한 바크 스케일(bark scale) 등 가 보상 밴드패스 필터에 적용하여 주파수 제한적인 음질 보상에 대한 실험을 통해 5.1채널 스피커 시스템에서 음향 재현시 나타나는 크로스토크를 제거함으로써 보다 입체적인 음을 재현하는 방법을 제안하였다. 정면 채널과 서라운드 채널의 음원을 기존의 2채널 및 5.1채널 시스템에서 제시하는 음원과 비교를 위하여 음질 평가와 함께 청취자를 대상으로 주관적인 평가를 실시하였다. 실험 결과 \pm30{\circ}$의 정면 스피커를 배치한 돌비 표준 스피커 배치에서 38dB 이상의 분리도를 얻었으며, 전문가 그룹의 음의 확산감에 대한 주관 평가에서는 5점 평가를 기준으로 0.4∼0.5점, 음의 깊이감 평가에서는 0.1∼0.2점이 향상되었다.

• 한국미생물·생명공학회지
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• 제44권3호
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• pp.268-277
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• 2016

본 연구는 COHEE의 항염증 효과를 확인하기 위한 실험으로써 pro-inflammatory cytokine의 분비량 및 iNOS, COX-2, NF-κB와 MAPKs의 발현량을 관찰하였다. 먼저 MTT assay를 통해 COHEE가 세포 생존율에 있어 독성을 나타내지 않음을 확인한 후 동일한 농도로 추후실험을 진행하였다. COHEE에 의해 NO 분비량이 농도 의존적으로 감소하였으며 IL-6, TNF-α 및 IL-1β의 분비량 또한 유의적으로 감소하였다. 특히 100 μg/ml의 농도에서 LPS 단독처리구인 대조구에 비하여 IL-6, TNF-α 및 IL-1β의 분비량을 각각 66%, 43% 및 93% 억제시켰다. 이러한 결과가 전염증성 매개인자의 전사인자인 NF-κB와 MAPKs 경로에 의한 것인지 확인하기 위하여 발현량을 관찰한 결과, COHEE가 LPS 처리에 의해 현저히 증가한 단백질의 발현을 농도 의존적으로 유의성 있게 억제하였다. 또한 COHEE는 croton oil로 부종을 유발한 마우스모델에서 귀부종 억제효과를 나타내었고 250 mg/kg 농도에서 조직의 경피 및 진피 두께의 발달을 prednisolone 10 mg/kg 처리구와 유사한 정도까지 현저히 억제시키고 염증성 세포인 mast cell의 침윤 억제 효과도 확인하였다. 이를 통해 COHEE는 염증 반응의 전사인자인 NF-κB의 발현을 조절함으로써 iNOS와 COX-2의 발현을 억제하고 그에 따라 전염증성 매개인자인 NO, IL-6, TNF-α 및 IL-1β의 분비를 억제하여 항염증 활성을 가지는 것을 확인하였으며, 이 결과를 종합해볼 때, COHEE가 염증 치료제로써의 소재로 이용될 가치가 충분할 것으로 사료된다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권3호
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• pp.210-217
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• 2011

Purpose: This study was to evaluate the synergistic effects of combined therapy of steroid and anti-neoplastic drug injection on hypertrophic scars in a rabbit model. Methods: Adult male white rabbits weighing about 2.5 kg were used. After full thickness wounding (about 6 mm) over the ventral surface of each ear sized was made, either saline (control group), triamcinolone, 5-fluoruracil, and mixture of triamcinolone and 5-fluoruracil were injected once 16 days after the wound was made. Rabbits were sacrificed 2, 4 and 8 weeks after injection, and tissue specimens were prepared for histologic and histomorphometric examinations. Results: With the combined injection of triamcinolone and 5-fluoruracil, collagen fiber thickness was arranged in a somewhat irregular manner 2 weeks after injection. After 4 weeks, blood vessels and inflammatory cells were decreased, and collagen fibers were arranged in an almost parallel manner. By 8 weeks, almost same amount of connective tissue compared with adjacent normal tissue was observed. Conclusion: These results indicated that combined injection of triamcinolone and 5-fluoruracil reduced the amount of hypertrophic scars by inhibition of fibroblasts and inflammatory cells. Therefore, combined injection of triamcinolone and 5-fluoruracil is a more potent and effective treatment of hypertrophic scars compared with the single injection of either triamcinolone or 5-fluorouracil.

• 한국산업보건학회지
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• 제21권3호
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• pp.162-167
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• 2011

To identify the relationship between types of job classification (typical and atypical) and the levels of recognition of noise and the hearing threshold shift, a total of 457 workers in a cosmetic company were studied utilizing a questionnaire and the audiometric hearing test. The results were analyzed by factor analysis, t-test, and general linear model, as appropriate. The results showed that atypical workers had higher level of noise recognition but had lower levels of hearing ability, noise exposure, and the knowledge on hearing loss prevention, compared with those of typical workers. The high noise level group of typical workers showed higher threshold shift levels than that of atypical workers. Significant differences were found at 4 kHz for both ears and in right ear only for hearing threshold shift after adjusting age.

• 한국식품영양학회지
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• 제23권4호
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• pp.440-445
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• 2010

Effect of brine mineral water(BMW) on contact hypersensitivity reaction(CHR) was estimated using trimellitic anhydride (TMA) induced CHR in the mouse. BMW exhibited potent inhibitory activity on TMA induced CHR. BMW treatment suppressed the ear swelling, and attenuated hyper-activated lymph nodes stimulated by TMA challenge, thereby reduced their weight. The immunological index was analyzed after BMW administration in CHR. The level of serum IgE was significantly down regulated after BMW treatment. Furthermore, BMW showed inhibitory property of cytokine production. BMW treatment suppressed not only Th2 type cytokine, IL-4 but also pro-inflammatory cytokines such as TNF-${\alpha}$ and IL-6. From the histological analysis, the inflammatory context appeared by atopic dermatitis lesion after challenging with TMA are diminished by BMW treatment. Our results suggest that BMW may attenuate the development of CHR, and can be available for functional ingredient.

• 한국식품저장유통학회지
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• 제16권3호
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• pp.449-453
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• 2009

The experiment was conducted to validate anti-inflammatory effects of pinitol from bean. It was evaluated for some molecule targets by wound healing assay and RT-PCR. The results of wound healing assay was shown dose-dependent inhibition of cell migration in cancer cells and inhibited RNA expression of ICAM-1, CD 44, MMP-17, MMP-14 and ARF2. Immune suppression activity in a mouse provoked by DNFB observed that inflammatory reaction with pinitol were reduced ear swelling and inflammatory cells infiltration in mouse atopic models. The result confirmed that pinitol have the effect of dose-dependent immune suppression activity.

• The International Journal of Costume Culture
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• 제3권1호
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• pp.30-40
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• 2000

The purpose of this research was to device thermal comfort model for radiation power plant workers in protective clothing. Three fabrics commonly used in protective workwear were made into coveralls of identical design and were evaluated by adult healthy males in four simulated work environment. It was investigated between the physiological response and subjects comfort according to environmental variance and clothing types. The of simulated work enviro mensent was controlled under four different humidity and temperature of each type. (Temperature 20±1℃, RH 40∼70%±5%, Temperature 30±1℃, RH 40∼70%±5%) An index of physiological response was connected with the thermal comfort designed. Mean skin temperature, skim temperature, Axillasy temperature ear canal temperature, clothing climate, total sweat, blood pressure, and R-R interval were be evaluated. Skin temperature difference ocurring during exercise and rest were significant only with respect to time and regions of the body, This despite physical differences in the three coveralls, particulary mass statistically experiment. Also, an index of subject wearing sensation was designed for thermal comfort after investigation determined the kind of clothes and the type of environment. As a result of this research, two types of multiple regressions was deviced to estimate thermal comfort of the protective clothing.

• 대한기계학회논문집B
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• 제21권9호
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• pp.1139-1148
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• 1997

Compression waves propagating in a high-speed railway tunnel develops large pressure fluctuations on the train body or tunnel structures. The pressure fluctuations would cause an ear discomfort for the passengers and increase the aerodynamic resistance of trains. As a fundamental research to resolve the pressure wave phenomenon in the tunnel, experiments were carried out by using a shock tube with an open end. A blockage to model trains inside the tunnel was installed on the lower wall of shock tube, thus forming a sudden cross-sectional area reduction. The compression waves were obtained by the fast opening gate valve instead of a conventional diaphragm of shock tube and measured by the flush mounted pressure transducers with a high sensitivity. The experimental results were compared with the previous theoretical analyses. The results show that the ratio of the reflected to the incident compression wave at the sudden cross-sectional area reduction increases but the ratio of the passing to the incident compression wave decreases, as the incident compression wave becomes stronger. This experimental results are in good agreements with the previous theoretical ones. The maximum pressure gradient of the compression wave abruptly increases but the width of the wave front does not vary, as it passes over the sudden cross-sectional area reduction.

• Journal of the Korean Wood Science and Technology
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• 제42권5호
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• pp.579-589
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• 2014

Atopic dermatitis (AD) syndrome is one of the most common and severe skin diseases in Korea; a large population has this disease. We examined the effects of the extract from the leaf and sprig of Camellia sinensis on the development of AD by using NC mice as a model of atopic dermatitis. Oral administration of the extract to NC/Nga mice treated with 2,4?dinitrochlorobenzene (DNCB) inhibited the development of AD-like skin lesions as shown by a significant decrease in the skin symptoms of the disease and a decrease in ear thickness and levels of immunoglobulin E (IgE) and thymus-and activation-regulated chemokine (TARC) level in the skin. Administration of the extract markedly suppressed the DNCB-induced mRNA expression of interleukin 4 (IL-4) and tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$). The findings suggest that transdermal application of the extract may modulate in the skin of NC/Nga mice. The extract was effective for the prevention and treatment of AD.