비만 개선 효과를 지닌 탄수화물 및 지방 흡수 억제 기능성 식이조성물 개발

윤유식,최선미,홍순복,홍정미,김정원,이홍석,홍성길 한국조리과학회 2002 한국식품조리과학회지 Vol.18 No.3

In a previous study, we developed a new food additive as an egg yolk antibody (IgY) against carbohydrate digestion enzymes for the regulation of blood glucose level and weight control. The IgY delayed and decreased the increment of blood glucose level after administration of sucrose in human being by 30% in 20∼30 min. We also developed a lipase inhibitor as a water extract of two kinds of herb, Platycodon grandiflorum and Solanum melongena. Twenty three volunteers were subjected to the intake of the egg yolk IgY plus the herbal extracts for 50 days. In average, the treated subjects appeared to lose 1.96 ㎏ of body weight and 3.4 ㎏ of body fat mass during the treated period. Furthermore, Panniculus adiposus and breech size were significantly decreased during the experimental period. Above results suggested that the administration of the dietary additives composed of egg yolk IgY and natural herbal extract improve the obesity by the decrement of body weight and body fat mass.

장내의 탄수화물과 지방 흡수 억제를 통한 체지방 및 비만 개선 효과에 관한 연구

정은희,윤승원,이홍석,윤유식,유경미,황인경 한국조리과학회 2003 한국식품조리과학회지 Vol.19 No.1

In a previous study, a dietary supplement was developed in our lab using natural herbal extracts against digest enzyme activity in GI tract for weight control. This natural herbal extracts could regulate absorption of glucose and lipid by the inhibition of digest enzyme activity. In this study, we screened the natural herbs that inhibit glucoamylase activity and developed an water extract of cinnamon. The cinnamon extract delayed and decreased the increment of carbohydrate degradation through the inhibition of glucoamylase activity in vitro. Fifty volunteers were subjected to the intake of the herbal extracts by taking twice a day for 60 days. As a result, the treated subjects lost 3kg of body weight and 3.5kg of body fat mass after the treatment. Furthermore, the body mass index and waist size were significantly decreased during the experimental period. Above results suggested that the administration of the dietary additives composed of cinnamon and natural herbal extract improves the obesity by the decrement of body weight and body fat mass.

Ti:LINbO₃ 채널 광도파로의 주기 분극반전 공정 개발에 관한 연구

鄭洪植 홍익대학교 산업기술연구소 2006 産業技術 Vol.16 No.-

A fabrication process of periodic electric field assisted poling of Ti-diffused channel waveguides in LiNbO_3 (Ti:PPLN) has been developed and improved using a periodically 180o phase inversion along y-axis. The zig for domain inversion and control program of poling current and charge has been devised. Pulse high voltage and duty cycle were adjusted based on the estimated current and charge required for poling inversion.

차세대 이동 위성서비스의 특성 분석

홍정식,안재경,김지표 한국정보사회진흥원 2005 정보화정책 Vol.12 No.4

1990대에 본격적으로 시작된 위성에 대한 연구를 바탕으로 국내에서는 무궁화 위성이 3호까지 성공적으로 운용되고 있으며, 곧 무궁화위성 5호도 발사될 예정에 있다. 현재 이러한 위성들은 통신, 방송용으로 지상망을 보완하는 역할을 수행하고 있으나, 차후 위성은 언제 어디서나 개인이 원하는 형태로 이용할 수 있는 초고속 멀티미디어 서비스를 제공할 예정이다. 본 연구에서는 미래 이동위성통신시스템의 원활한 개발을 위하여 필수적으로 수반되어야 하는 차세대 유망 위성서비스에 대한 다양한 분류작업과 지상망 대비 경쟁력 검토를 하였으며, 이를 바탕으로 양방향 HDTV, 양방향 DMB, LBS와POS, PPDR, DCD, Glass Vision, 실시간 여행/운전 안내, 자동 정보 업데이트, 산간/오지의 인터넷 등 9개의 유망 위성서비스를 도출하고 그 특성을 분석하였다. 또한 이들 서비스를 심층 분석한 결과 재난정보 서비스, 디지털 콘텐츠 분배서비스, 그리고 산간/오지 인터넷 서비스가 보다 경쟁력 있는 서비스로 드러났다.

전기광학 변조기에 대한 진행파형 전극구조의 위상정합에 관한 연구

鄭洪植 홍익대학교 산업기술연구소 1992 産業技術 Vol.1 No.-

The characteristics of traveling-wave electrodes for high-frequency electrooptic integrated devices are described from the the view point of improvement of phase-matching based on the conformal mapping method. specific calculations of the characteristic impedance, effective microwave index, and electrode loss for asymmetric coplanar strip (ACPS) and coplanar waveguide(CPW) electrode structures are presented as a function of the geometric electrode parameters including the electrode thickness and buffer layer thickness. 5∼10(㎛) thick Au-ACPS electrodes were successfully fabricated by electroplating and ECR etcher. The improvement of modulation bandwidth can be theoretically observed from the combination of electrode and buffer layer thickness.

Film-Loaded 음향파 도파로를 이용한 Ti:LiNbO₃ 음향광학 파장가변 광 필터에 관한 연구

鄭洪植 弘益大學校 産業技術硏究所 2004 産業技術 Vol.14 No.-

An optimum Hamming apodized acousto-optic tunable filter using SiO₂ film loaded acoustic waveguide with angular offset to the Ti:LiNbO₃ waveguide were fabricated. Insertion loss <7.1㏈ has been obtained and side-lobe of ∼19㏈ for ∼32㎽ RF driving power has been realized. A TE↔TM polarization mode convertible performance has been confirmed and a linear tuning rate of 8.1㎚/㎒ and a 3㏈ spectral width of ∼1.5㎚ were demonstrated.

Ti:LiNbO3 채널 광도파로를 이용한 집적광학 편광조절기에 관한 연구

鄭洪植 弘益大學校 産業技術硏究所 2005 産業技術 Vol.15 No.-

We investigated a LiNbO3 based integrated-optic polarization controller with the Ti-indiffused waveguide along the z-axis utilizing the electro-optic effect. The device consists of a first quarter-wave (λ/4) phase-shifter followed by a half-wave(λ/2) and a second quarter-wave(λ/4) wave-plate, which is rotated synchronously with first quarter-wave phase-shifter. We analyzed the operation principles of the device utilizing cascaded transfer matrices based on Jones matrix and Poincare sphere, simulated driving voltages for various input state of polarization (SOP), and theoretically confirmed transformations from any arbitrary input SOP into any general output SOP.

LiNbO_3의 음향광학효과형 가변파장 광여파기의 다채널 동작 특성에 관한 연구

鄭洪植 홍익대학교 산업기술연구소 2000 産業技術 Vol.10 No.-

We have demonstrated a 8㏈ additional reduction in the intensity sidelobes of an apodized interaction strength guided-wave acousto-optic filter with a center passband of 1551㎚. Acoustic-intensity weighting was achieved by launching a surface acoustic wave (SAW) in a straight acoustic waveguide, and gradually transferring this SAW intensity to active device, and back out. The sidelobes were reduced to -12.68㏈ for a SAW intensity with raised-cosine weighting. Polarization conversion in excess of 90% and a spectral width of 2.15㎚ and 1.95㎚ for both transverse electric(TE) and transverse magnetic (TM) input polarizations, respectively were achieved at a wavelength 1551.6㎚ and RF frequency of 173.58㎒ with driving power 17.78㎽. We demonstrate an integrated acousto-optic tunable filter in a multiwavelength selection experimental systems with 2 channels present.

전기광학 방향성 결합 스위치의 왜곡 개선에 관한 연구

鄭洪植 홍익대학교 산업기술연구소 1996 産業技術 Vol.6 No.-

We have developed a simple link model that calculates harmonics and intermodulation distortion by Fourier-analyzing the link output when a two-tone input signal is applied. We have applied the model to directional coupler modulators with zero, one or two additional dc-biased regions to enhance linearity. We find that harmonics and intermodulation produced no longer exhibit a simple constant exponent power law behavior with the input signal, and we propose a new unambiguous definition of dynamic range to cope with this added complexity. For a sample set of parameters, we calculate that improvements of about 20 dB in dynamic range are obtainable at a sacrifice of 10 dB in gain and noise figure, but that the directional coupler modulator must be tightly controlled to realize such an improvement.

2×2 Ti:LiNbO_(3) 디지털 광 스위치 설계 및 제작

鄭洪植 홍익대학교 산업기술연구소 2003 産業技術 Vol.13 No.-

We propose and demonstrate a novel polarization- and wavelength-independent digital electro-optic switch in Ti:LiNbO_(3) with switching voltage of ±32V at 1.55㎛ wavelength. This 2×2 integrated optic switch is characterized by a step-like response to the applied voltage. Switching is achieved through adiabatic eigenmode transformation in an asymmetric waveguide junction. The average insertion loss of ~4.5㏈/㎝ and polarization independent switching with average cross-talk of -12㏈ are achieved.