• 한국염색가공학회지
• /
• 제10권6호
• /
• pp.55-66
• /
• 1998

In order to investigate the detergency effects of various detergents to stained polyester & cotton fabric with solid soils such as carbon black, liquid paraffin and fat, the optimum washing conditions according to the types of washing agent, the assesment of detergency effect by the measurement of reflectance after and before washing were studied. The detergency effect of various detergents to stained polyester and cotton fabric increased by using the mixtures of bleaching and enzyme detergent. In order to obtain the excellent detergency effect, 2-step treatment, the pre-washing with bleaching agent and bleaching-enzyme mixture detergent treatment is preferred. In comparison of the detergency to polyester and cotton fabric, it is assumed that the detergency to polyester stained fabric was superior than that to cotton stained fabric because of the difference of adhesive force between soil material and fabric in preparing solid stained fabric.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2001년도 학술발표회 발표논문집
• /
• pp.505-508
• /
• 2001

Remote Sensing is one of effective methods for collecting, analyzing information and predicting the change of agricultural environments. The RS technique is based on the principle that the object reflects a peculiar radio wave according to types and environmental conditions. For collection RS base data, used spectroradiometer which measures reflection characteristics between $300{\sim}1,100nm$ and measured the reflection of Mi-ho stream's water resources which is located thong-won, Chung-buk province, Korea. The difference of reflectance represents the characteristic of bottom soil, water color and matters in water.

• 산업기술연구
• /
• 제24권B호
• /
• pp.59-64
• /
• 2004

GaAs thin films were grown epitaxially by MOCVD method on (001) GaAs substrate. And as a surfactant, Bi(bismuth) thin films were deposited on GaAs buffer layer by using TMBi(trimethylbismuth) source. In-situ reflectance difference spectroscopy(RDS) was used to monitor the surface reconstruction of GaAs and Bi thin films. As the results, under the exposure of TBAs(tertiarybuthylarsine) and hydrogen atmosphere, the surface reconstruction of GaAs was changed from As-rich c($4{\times}4$) to As-rich ($2{\times}4$), which was due to the adsoption and desorption of As dimers. The first bismuth surface related RDS signal was reported. At the deposition temperature of $450^{\circ}C$, Bi-terminated GaAs surface showed the RDS spectrum similar to that of Sb-terminated GaAs surface, possibly a ($2{\times}4$) surface. And Bi surface layers were rapidly evaporated with increasing the deposition temperature($550^{\circ}C$), finally becoming As-terminated ($2{\times}4$) surface.

• Current Optics and Photonics
• /
• 제1권6호
• /
• pp.626-630
• /
• 2017

GaN-based green light-emitting diode (LED) structures suffer from low internal quantum efficiency (IQE), known as the "green gap" problem. The IQE of LED structures is expected to be improved to some extent by exploiting the Purcell effect. In this study, the Purcell effect on the IQE of green LED structures is investigated numerically using a finite-difference time-domain simulation. The Purcell factor of flip-chip LED structures is found to be more than three times as high as that of epi-up LED structures, which is attributed to the high-reflectance mirror near the active region in the flip-chip LED structures. When the unmodified IQE is 20%, the relative enhancement of IQE can be greater than 50%, without utilizing the surface-plasmon coupling effect. Based on the simulation results, the "green gap" problem of GaN-based green LEDs is expected to be mitigated significantly by optimizing flip-chip LED structures to maximize the Purcell effect.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2008년도 제39회 하계학술대회
• /
• pp.1114-1115
• /
• 2008

In this paper, we study the optical characteristics of low iron glass for photovoltaic modules fabrication. Tow types of glasses are examined by optical transmittance and reflection measurement. Also, by making laminated glass, we analyze the difference between glass maker. Mini-PV module is fabricated to compare optical reflectance through lamination process. Anti-reflection and catalyst-coated glasses are suggested for advanced technology to obtain high electrical generation output. The specific analysis is shown in the following paper.

• 대한가정학회지
• /
• 제37권2호
• /
• pp.113-126
• /
• 1999

In order to investigate the detergency effect of stained cotton and PET fabric, respectively, these fabrics stained with solid soils such as carbon black, liquid paraffin, and fat and examined the detergency effect in the optimum washing condition. The evaluation of washing efficiency of washed fabrics studied by using the surface reflectance measurement before and after washing treatment. The maximum detergency effect of stained cotton and PET fabric obtained in the mixed washing liquor-bleachig agen(ml)/concentrated washig agent(g/l). To obtain the excellent detergency effect, 2-step washing treatment, pre-washing by bleaching agent only and washing by concentrated detergent, is preferred. In comparing the detergency of polyester and cotton fabric, the detergency of stained polyester fabric superior than that of stained cotton fabric because of the difference of adhesive force between soil material and fabric in preparing soled stained fabric. In this study, we also studied the degree of fabric damage by the measurement of tensile strength change. From the results of the tensile strength measurement, the damage of washed fabric before and after washing treatment was nearly changed.

• 한국인쇄학회:학술대회논문집
• /
• 한국인쇄학회 2000년도 춘계 학술발표회 논문집
• /
• pp.25-34
• /
• 2000

Recently, color proofing in printing industry grow rapidly. If an order decide color from known color information in the case of color reproduction, we can reduce expenses and time. In color proofing the best important point must be closed proofed color to primary color and secondary color. Model-based approaches have the advantages of faster recharacterization and the opportunity of simulating product enhancements such as changes in ink properties and halftoning. In this paper, we transformed the dot area of CMYK to CIELAB color space using color reprodution models. Firstly, we measured spectral reflectance of primary color printed by Matchprint II and the data was used to find tone reproduction curve using regression equation, and than we applied at primary color model, such as Murray-Davies, Yule-Nilsen, and mixed color model, such as Kubelka--Munk, relaxed version of spectral Neugebauser. In such results, the Kubleka-Munk model resulted in the best spectral reconstruction accuracy followed by relaxed version of spectral Neugebauer model, color difference is 2.8401.

• 한국인쇄학회지
• /
• 제18권2호
• /
• pp.29-40
• /
• 2000

Recently. color proofing in printing industry grow rapidly. If an order decide color from known color information in the case of color reproduction, we can reduce expenses and time. In color proofing the best important point must be closed proofed color to primary color and secondary color. Model-based approaches have the advantages of faster recharacterization and the opportunity of simulating product enhancements such as changes in ink properties and halftoning. In this paper, we transformed the dot area of CMYK to CIELAB color space using color reproduction models. Firstly, we measured spectral reflectance of primary color printed by Matchprint II and the data was used to find tone reproduction curve using regression equation, and than we applied at primary color model, such as Murray-Davies, Yule-Nilsen, and mixed color model, such as Kubelka-Munk, relaxed version of spectral Neugebauer. In such results, the Kubelka-Munk model resulted in the best spectral reconstruction accuracy followed by relaxed version of spectral Neugebauer model, color difference is 2.8401.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
• /
• pp.1203-1205
• /
• 2003

To detect dust-loaded air-mass over land and ocean, we propose an index, which is essentially the difference in Rayleigh-corrected reflectance between 412 and 443 nm bands of SeaWiFS. Radiative transfer simulations are conducted to show that the index is linearly related to the optical thickness of modeled dust-contaminated aerosol while showing insensitivity against non-absorbing model aerosols. Asian SeaWiFS data set of 2001 spring is used to produce daily composite imagery of the index, which compares well with TOMS Aerosol Index and with predicted aerosol optical thickness predicted by CFORS chemical weather forecast.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
• /
• pp.706-708
• /
• 2003

Index for difference of vegetation surface roughness (BSI: Bi-directional reflectance factor structure Index) was proposed in our laboratory (Konda et al., 2000). It is thought that BSI is useful vegetation index for vegetation monitoring. If it can be applied for global covered satellite data, detailed monitoring of global vegetation can be expected. However, in order to apply BSI to global satellite data, there are some problems to be solved. In this study, in order to make global data set of BSI, it arranged about processing of the global satellite data for making BSI data sets.