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Wind speed is the main factor responsible for the increase in ocean thermal emission because sea surface emissivity strongly depends on surface roughness. An alternative approach to estimate the surface wind speed (SWS) as a function of surface roughness is developed in this study. For the sea surface emissivity, the state-of-the-art forward Fast Microwave Emissivity Model, version 3 (FASTEM-3), which is applicable for a wide range of microwave frequencies at incidence angles of less than 60°, is used. Special Sensor Microwave Imager and Advanced Microwave Scanning Radiometer (AMSR-E) observations are simulated using FASTEM-3 and the Global Data Assimilation and Prediction System operated by the Korea Meteorological Administration. The performance of the SWS retrieval algorithm is assessed by comparing its SWS output to that of the Global Data Assimilation System operated by the National Centers for Environmental Prediction. The surface roughness is computed using the Hong approximation and characteristics of the polarization ratio. When compared with the Tropical Atmosphere–Ocean data, the bias and root-mean-square error (RMSE) of the SWS outputs from the proposed wind speed retrieval algorithm were found to be 0.32 m s−1 (bias) and 0.37 m s−1 (RMSE) for the AMSR-E 18.7-GHz channel, 0.38 m s−1 (bias) and 0.42 m s−1 (RMSE) for the AMSR-E 23.8-GHz channel, and 0.45 m s−1 (bias) and 0.49 m s−1 (RMSE) for the AMSR-E 36.5-GHz channel. Consequently, this research provides an alternative method to retrieve the SWS with minimal a priori information on the sea surface.

The input parameters of scattering models for computing the backscattering coefficients of earth terrains are mainly soil moisture and surface roughness. The backscattering coefficients of soil surfaces are more sensitive to surface roughness than soil moisture. In this study, we propose a precise measurement method for roughness parameters and analyze measurement errors. We measured surface roughness using a pin-board profiler(1 m, 0.5 cm interval) and a laser profiler(1 m, 0.25 cm interval). The measurement differences between two profilers in an average sense are 0.097 cm for root-mean-square (RMS) height and 1.828 cm for correlation length. The analysis of the correlation functions and relative errors shows that the laser measurements are more stable than the pin-board measurements. The differences of the calculated backscattering coefficients using a surface scattering model between pin-board and laser profiler measurements are less than 1 dB.

Phosphor-converted white-light-emitting diodes (WLEDs) were fabricated using the open remote method. The separation distance between the blue LED chip and phosphor layer was varied to examine the effects of blue lights penetrating through the annular gaps between the phosphor layer edge and reflector cup walls on the luminous efficiency of the WLED. The WLEDs with a separation distance of 0.55 mm showed the highest luminous efficiency which was close to that of the slurry sample, while the amount of phosphors used was less than 25% of the amount used in the slurry sample. These results suggest that the phosphor quantity used for fabricating the WLEDs can be reduced considerably by the open remote method without any significant loss of luminous efficiency.

A Cu2ZnSnS4(CZTS) film was formed by the sulfurization of Cu(Zn, Sn) (CZT) alloy precursors. The sulfurization was performed in evacuated and sealed quartz ampoules with various amount of supplied sulfur powder. The crystallization of the CZTS films as a function of the sulfur content was determined based on X-ray diffraction (XRD) patterns. The XRD analysis indicated that the Cu-Sn/Zn metal precursor was crystallized with various secondary phases, such as ZnS, Cu2S, Cu3Sn, Cu2SnS3, and Cu2SnS7. We also found that the energy gap of CZTS absorber was 1.48–1.51 eV.

Cu2ZnSnSe4(CZTSe) films were formulated by the selenization of Cu(Zn, Sn) (CZT) metal precursors. The CZT precursor was prepared by depositing zinc onto a Cu-Sn layer co-sputtered on molybdenum-coated soda-lime glass substrates. Selenium was evaporated thermally onto the CZT precursor. The resulting CZTSe film was then annealed at 450 °C for various annealing times (1, 3, 5, 10 and 15 min) using a rapid thermal process (RTP). Crystallization of the CZTSe film as a function of the annealing time was observed by X-ray diffraction (XRD). The XRD patterns of the films annealed over 3 min were well matched to those of a CZTSe single crystal. The lattice parameters of the CZTSe films annealed over 5 min were a = 5.639 A and c = 11.356 A. These values were reasonably close to the lattice parameters of a single crystal of Cu2ZnSnSe4(a = 5.693 A and c = 11.333 A). The energy gap of the CZTSe films was 1.14 eV.

This article presents a geostatistical approach for downscaling precipitation products from passive microwave satellites with geostationary Meteorological Satellite observations. More precisely, the Advanced Microwave Scanning Radiometer 2 (AMSR2) precipitation (daily level 3 product) with 0.25° spatial resolution and the Communication, Ocean and Meteorological Satellite (COMS) infrared (IR) data with 5 km spatial resolution were used for the downscaling experiment over the Korean peninsula. Brightness temperature data observed at COMS IR 1 and water vapour channels were incorporated for downscaling via area-to-point residual Kriging with non-linear regression. The evaluation results with densely sampled Automatic Weather Station data revealed that incorporating the COMS IR observations with the AMSR2 precipitation showed similar error statistics to those of the AMSR2 precipitation because of the limitations of IR observations themselves and the inherent errors of the AMSR2 precipitation product over land. However, the area-based evaluation using information entropy indicated that incorporating the COMS observations resulted in more detailed spatial variation in the final product than direct downscaling of the AMSR2 precipitation. In addition, local precipitation patterns could be captured when there were regions with missing precipitation values in the AMSR2 product. Consequently, the downscaling result is useful for understanding the local precipitation patterns with an accuracy similar to that provided by microwave satellite observations. It is also suggested that the spatial variability in the downscaling result and errors in input low-resolution data should be considered when downscaling coarse resolution data using fine resolution auxiliary variables.

L밴드 ALOS SAR 자료를 활용하여 우리나라 동해 연안해역의 해상풍을 산출하고 오차의 특성을 분석하였다. 그 동안 인공위성 산란계를 이용한 해상풍 산출이 본질적으로 불가능하였던 연안 해역에 대하여 SAR 자료로부터 고해상도 해상풍을 산출할 수 있었다. 산출된 SAR 바람을 해양 부이 자료와 비교한 결과 0.67 m/s의 작은 오차로 잘 일치함을 보여주었다. 서로 다른 L밴드 ALOS PALSAR GMF 2007 모델과 2009 모델로 산출된 해상풍을 인공위성 산란계 해상풍과 비교한 결과, 풍속과 풍향 각각 2.16 m/s와 19.24°, 3.62 m/s와 28.02°의 제곱평균근오차를 보이며, 인공위성 산란계의 기대 오차보다 다소 큰 경향을 나타냈다. 또한 산출된 L밴드 SAR 바람장은 풍향과 입사각에 대하여 특징적인 의존성을 보였다. L밴드 GMF 2007 모델은 21°보다 작은 입사각에 대하여 큰 오차를 보인 반면, L밴드 GMF 2009 모델은 입사각에 대한 효과를 선형함수가 아니라 이차함수로 고려하여 주었기 때문에 작은 입사각 범위에서 풍속 오차가 6.8 m/s에서 1.14 m/s로 크게 감소하는 결과를 보였다. 본 연구는 L밴드 SAR 바람장의 다양한 활용을 위해서는 풍향과 입사각 효과, 그리고 다른 잠재적인 오차의 요인을 집중적으로 연구하여야 함을 강조하였다.

Cu(Zn, Sn)(CZT) metal precursors were deposited on glass substrates by an RF-magnetron sputtering method for use in CZT-based solar cells. Recently, researches have shown that CZT-based solar cell films prepared with a metal precursor with a rough surface morphology produce a low conversion efficiency. A single layer of tin (Sn) grown on a substrate has a rough surface morphology. In this study, the co-sputtering method was used, wherein Zn, Cu, and Sn layers were deposited on co-sputtered layers of Cu-Sn, Zn-Sn, and Cu-Zn, respectively. From an atomic force microscopy analysis, the root-mean-square surface roughness of the Zn/Cu-Sn layer was found to be 12.3∼14.3 times smaller than that of the other layers precursors, Cu/Zn-Sn, and Sn/Cu-Zn.

A Cu2ZnSnSe4 (CZTSe) film was formed by the selenization of Cu(Zn, Sn) (CZT) alloy precursors. The CZT precursor was prepared by depositing zinc onto a layer of Cu-Sn co-sputtered on molybdenum-coated soda-lime glass. Selenium was evaporated on the CZT precursor. The CZTSe film was then annealed for a minute at various substrate temperatures ranging from 350°C to 650°C in steps of 50°C in a rapid thermal process using tungsten halogen lamps. The lattice parameters of the CZTSe annealed at temperatures over 500°C were found to be a = 5.709 A and c = 11.351 A. We also found that the energy gap of the CZTSe was 1.137 eV, which was independent of the annealing temperature.

We investigate the particle size dependence of the relaxivity of hydrogen protons in an aqueous solution of iron oxide (Fe3O4) nanoparticles coated in silica for biocompatibility. The T1 and T2 relaxation times for various concentrations of silica-coated nanoparticles were determined by a magnetic resonance scanner. We find that the relaxivity increased linearly with increasing particle size. The T2 relaxivity (R2) is more than 50 times larger than the T1 relaxivity (R1) for the nanoparticle contrast agent, which reflects the fact that the T2 relaxation is mainly influenced by outer sphere processes. The high R2/R1 ratio demonstrates that silica-coated iron oxide nanoparticles may serve as a T2 contrast agents in magnetic resonance imaging with high efficacy.

The phase change material (PCM) could be added to the wallboard to increase the thermal mass to decrease in indoor temperature fluctuation and improve thermal comfort. In this study, experimentally validated simulation was performed to investigate the effects of various parameters of PCM including the nominal average phase change temperature, its range, the convective heat transfer coefficients and the wallboard thickness on the thermal storage performance of the wallboard such as the thermal energy storage and the time shift. It was found that the average phase change temperature should be close to the average room temperature to maximize the thermal heat storage in the wallboards. The phase change temperature should be narrow to maximize the thermal heat storage in the PCM wallboards. The thermal heat storage increased with the convective heat transfer coefficient, and the optimal average phase change temperature to maximize the storage shifted a bit to a higher temperature with it. The time shift was found to decrease with the convective heat transfer coefficient and the phase change temperature range.

Summary Surface soil moisture plays a key role in water and energy exchanges at the land–atmosphere interface. Previous research on the microwave remote sensing of soil moisture focused mostly on the forward modeling problem. This paper presents a unique inversion algorithm (Hong’s algorithm) for soil moisture retrieval with reduced degrees of freedom of the Fresnel equation; the algorithm is based on the characteristics of the polarization ratio for rough surfaces around the Brewster angle and Hong’s approximation, which is an approximate relationship between vertically and horizontally polarized reflectivities. Using the daily observations of the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) taken at 0.25° × 0.25° pixel, the soil moisture is estimated globally over the land surface using a relation between the complex dielectric constant and the soil moisture after retrieving the surface roughness and complex dielectric constant. The surface soil moisture products obtained from Hong’s algorithm are validated using in situ observations carried out in Oklahoma and Georgia in 2003. The official AMSR-E soil moisture products are compared to assess Hong’s algorithm using identical brightness temperature data sets. The biases and the root mean squared error calculated in comparison with the ground observations are in the range of −0.059 m3/m3 to 0.01 m3/m3 and 0.023 m3/m3 to 0.065 m3/m3, respectively. Hong’s algorithm estimates the soil moisture within the estimated accuracy of AMSR-E surface soil moisture, 0.06 m3/m3, without requiring a priori information about the roughness and the dielectric constants of the surface. With a minimal use of forward models, this research could also be applied to global soil moisture retrieval in the Soil Moisture and Ocean Salinity satellite mission and the Soil Moisture Active/Passive mission.

Significant deviations between published results have been reported measuring the effective thermal conductivity of nanofluids with the transient hot-wire method (THWM). This may be attributed to a poor selection of the temperature data range, which should meet the following conditions. The start time should be chosen after the conductive heat flux delay time, while the end time should be selected before a crossover point when natural convection becomes significant. Considering an EG-based 1.06 vol.% ZnO nanofluid, the thermal conductivity was measured to increase by 5.4% over that of the base fluid.

An anti-reflection (AR) layer of Teflon AF was deposited on the front surface of a Cu(In,Ga)Se2 (CIGS) solar cell with a structure of grid/TCO/ZnO/CdS/Cu(In,Ga)Se2/Mo/glass by using the spin coating method. This AR layer reduced the front-surface reflection, which resulted in high efficiency for the CIGS solar cell. The thickness of the Teflon AF layer was varied to determine the thickness that gave the highest transmittance of incident light into the active absorber of the CIGS solar cell. The optimum thickness of the Teflon AF layer was found to be 105 nm. CIGS solar cells with a Teflon AF layer of 105 nm were constructed, and their efficiencies were compared with those of solar cells without a Teflon AF layer. The average increase in the relative efficiency of the solar cells was 2.63% due to the inclusion of an anti-reflection layer of Teflon AF.

Sea ice is one of the most important parameters in the global climate system, specifically the exchange of energy and momentum between the ocean and the atmosphere. In previous studies, a steady decline in Arctic sea ice has been observed over recent decades. The aim of this study is to estimate and analyze the spatial and temporal characteristics of the averaged sea ice extent, surface roughness, and refractive index from March 2003 to September 2009. A unique inversion algorithm is used for deriving the surface roughness and refractive index from Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) daily observations. Surface roughness significantly affects the microwave emission of the sea ice/snow surface. The sea ice, snow, and water show the dielectric contrast in the microwave frequencies. Consequently, the averaged roughness as well as the sea ice extent shows a downward trend, while the averaged refractive index shows the opposite signature. The increased trend of the refractive index in summer on both poles supports more sea ice melting in summer because of the increased temperature. This research can be applied to the climate change studies and supports the previous approaches based on the sea ice concentration in passive microwave remote sensing by the physical explanations.

Recently, nanofluid is a hot research topic among thermal engineers to enhance the heat transfer. However, there are deviations between research groups in the effective thermal conductivity measurements by the transient hot-wire method. Since there has been no report for the researchers to select a proper data range of temperature to estimate the thermal conductivities, the deviation could be partly attributed to the poor selection of the temperature data range. In this study, the impacts of the data range selection, the power supplier response delay, the thermal coefficient of resistors, the hot-wire type and test section size on the thermal conductivity measurement using the transient hot-wire method are analyzed. The proper selection of the temperature data range to be used to estimate the thermal conductivities of fluids using transient hot-wire method is suggested by investigating the impact of it on the measurement by both computationally and experimentally. The thermal coefficient of resistor is found to affect the measurement seriously whereas the type of hot-wire does not. The test section size of the measuring device is compared with the thermal penetration depth.

Summary In various hydrological processes, surface soil moisture is very sensitive to the surface roughness. The surface roughness effect has been incorporated into the calculation of surface reflectivity by modifying the Fresnel reflectivity. The objective of this study is to estimate the small-scale roughness based on the difference of polarization between the rough and specular reflectivities over land at microwave frequencies. A unique approach is presented to estimate the small-scale roughness from the surface reflectivity with the microwave satellite observation. Using an approximate relationship between vertically and horizontally-polarized reflectivities, and rough reflectivity based on the radiative transfer equation and satellite observation, the small-scale roughness is retrieved globally over land surfaces. A realistic forward model to simulate the rough reflectivity is considered for the sensitivity test. Consequently, the small-scale roughness is retrieved within the reasonable range of previous works. This research proposes a unique technique to understand and estimate the roughness parameter over land surface by using the polarization characteristics at microwave frequencies; this research provides information that is extremely relevant to hydrological studies, especially for the global soil moisture retrieval in the SMOS, SMAP, and GPM missions.

The characteristics of the polarization ratio in the case of rough surfaces are investigated. In addition, an inversion method is also proposed for retrieving the surface roughness over land and sea. The proposed method was effective for angles of incidence near the Brewster angles close to the view angles of many satellite microwave sensors. This new method retrieves the sea surface roughness within a reasonable range of bias. Consequently, this study provides insight into the polarization ratio and an inversion method to estimate the surface roughness by using the characteristics of the polarization ratio from passive microwave remote sensing.

Polar ice masses and sheets are sensitive indicators of climate change. Small-scale surface roughness significantly impacts the microwave emission of the sea ice/snow surface; however, published results of surface roughness measurements of sea ice are rare. Knowing the refractive index is important to discriminate between objects. In this study, the small-scale roughness and refractive index over sea ice are estimated with AMSR-E observations and a unique method. Consequently, the small-scale surface roughness of 0.25 cm to 0.5 cm at AMSR-E 6.9 GHz shows reasonable agreement with the results of known observations, ranging from 0.2 cm to 0.6 cm for the sea ice in the Antarctic and Arctic regions. The refractive indexes are retrieved from 1.6 to 1.8 for winter, from 1.2 to 1.4 for summer in the Arctic and the Antarctic, which are similar to those of the sea ice and results from previous studies. This research shows the physical characteristics of the sea ice edges and melting process. Accordingly, this investigation provides an effective procedure for retrieving the small-scale roughness and refractive index of sea ice and snow. Another advantage of this study is the ability to distinguish sea ice from the sea surface by their relative small-scale roughness.

Many satellite remote sensors perform unpolarized measurements. A systematic procedure to decompose measured unpolarized emissivity is proposed using the definition of total reflectivity and the relationship between vertically and horizontally polarized reflectivity. Two polarizations are retrieved for various view angles with mixed emissivity simulated using the refractive index of water for ultraviolet, visible, infrared and microwave wavelengths. The results indicate that the absolute bias errors are small and consistent within Brewster angles, irrespective of the wavelengths. However, the relative bias is less than 4% and 5% for vertical and horizontal polarization, respectively, for any instrument working at infrared and microwave wavelengths. The relative bias for horizontal polarization is 20-30% for ultraviolet and visible wavelengths due to small absolute reflectivity values. Consequently, the method proposed in this study is applicable to specular surfaces for various view angles without the dielectric properties of a medium being required.

Accurate models of surface emissivity are important for interpreting satellite radiance observations. Surface emissivity depends on the satellite zenith angle, roughness, polarization, and refractive index of the surface. The effects of the roughness parameter on emissivity have not been studied thoroughly. By using an infrared geostationary satellite observation and a physical model based on the radiative transfer equation, the forward emissivity model and physical emissivity model are validated in the northwestern Pacific Ocean. First, the unpolarized emissivity at a given view angle and a wavelength of 10.8 μm in the thermal infrared spectral region is decomposed for the clear sky. The refractive index of the sea surface is quantitatively retrieved using the inversion of Fresnel equations. The refractive index of the sea surface derived from the physical emissivity exhibits a reasonable range within the infrared wavelength. The result of this investigation can be applied to the land emissivity model, which has not been studied thoroughly.

The rate-distortion optimization (RDO) method in the H.264/AVC encoder is a technology that improves the coding efficiency, but increases the computational complexity. In this paper, a fast Intra mode decision algorithm using DCT (Discrete Cosine Transform) coefficients distribution is proposed to reduce the H.264 encoder complexity. The proposed method reduces the encoder complexity on average 68.40%, while the coding efficiency is slightly decreased compared with the H.264/AVC encoder. Keyword: Video coding, H.264/AVC, Encoder, Fast mode decision, Intra mode decision

The periodical occurrence of Asian dust (Hwangsa) in East Asia during every spring and winter is of great consequence to regional human health and visibility. One weakness of the previous methods based on the brightness temperature (BT) differences or optical depths is that they can not accurately detect the dust events over the Yellow Sea. This study proposes a unique technique of decomposing unpolarized reflectivities to distinguish between dust and clouds over the sea surface. Many current infrared (IR) satellite instruments such as MTSAT-1R measure the unpolarized radiance. In this process, an approximate relationship between vertically and horizontally polarized reflectivities is validated for the IR wavelengths of 3–12 μm. The radiances observed from an IR geostationary satellite and the simulated sea surface temperature (SST) are used for a case study of Asian dust events. The results show qualitatively the reasonable spatial agreements with MODIS true color images for these Asian dust events. The proposed method in this study can be utilized for the operational purpose to detect the signal of Asian dust over sea surface.

The reactive force-field (ReaxFF) interatomic potential is a powerful computational tool for exploring, developing and optimizing material properties. Methods based on the principles of quantum mechanics (QM), while offering valuable theoretical guidance at the electronic level, are often too computationally intense for simulations that consider the full dynamic evolution of a system. Alternatively, empirical interatomic potentials that are based on classical principles require significantly fewer computational resources, which enables simulations to better describe dynamic processes over longer timeframes and on larger scales. Such methods, however, typically require a predefined connectivity between atoms, precluding simulations that involve reactive events. The ReaxFF method was developed to help bridge this gap. Approaching the gap from the classical side, ReaxFF casts the empirical interatomic potential within a bond-order formalism, thus implicitly describing chemical bonding without expensive QM calculations. This article provides an overview of the development, application, and future directions of the ReaxFF method.

The development of latent skin impressions on a variety of fabrics (cotton, rayon, polyester, nylon, and acrylic fabrics in five colors; white, black, yellow, blue and red) has been studied. Squid soaked in artificial sweat solution or de-ionized water was used as an alternative to human skin to make skin impressions on the fabric. A piece of squid was subjected to a constant force, to transfer the skin components onto the fabric. The fabrics bearing the skin impressions were treated with various reagents such as ninhydrin, 1,8-diazafluoren-9-one (DFO), 1,2-indanedione/ Zn (1,2-IND/Zn), Amido black and Hungarian red, to know the most effective method for developing the skin impressions on the fabrics. Comparing the sensitivity of the reagents, stronger development was observed from the impressions made with the artificial sweat soaked squid than the de-ionized water soaked squid. These results show that the development quality of the latent hit mark is influenced by the sweat, as well as other skin components. Also, the development efficiency of the reagents varied depending on the chemistry, color and texture of the fabric. Therefore, before the development of skin impressions on the evidence fabrics, it is suggested to perform a preliminary experiment with different methods on a similar fabric to decide the most sensitive method.

An improved oceanic rainfall algorithm based on a radiative transfer model that reduces many uncertainties of rainfall retrieval was developed using advanced microwave scanning radiometer for Earth Observing System data. Error models were embedded to quantify rainfall uncertainties and to reduce net uncertainties. Six channels (37, 18, and 10 GHz with dual polarization) were utilized in the algorithm. Several developments such as improvement of the freezing-level (FL) retrieval, a weighted average scheme, and enhanced offset correction were implemented in this paper. As a result, rain rate uncertainties were substantially reduced and quantified. To establish error models, drop-size-distribution uncertainty, beam filling error, data calibration uncertainty, and instrument noise were taken into account. These error models were used to compute proper weights of each channel to combine the six rain rates. The algorithm was evaluated with respect to the current operational algorithm (NASA Level 3 rainfall algorithm). It showed more reasonable mean FLs and rain rate estimation than the operational algorithm. Furthermore, pixel-by-pixel-based quantitative error estimates were conducted through the error model

In order to study fingerprinting in the field of forensic science, it is very important to have two or more latent fingerprints with identical chemical composition and intensity. However, it is impossible to obtain identical fingerprints, in reality, because fingerprinting comes out slightly differently every time. A previous research study had proposed an artificial fingerprint creation method in which inkjet ink was replaced with amino acids and sodium chloride solution: the components of human sweat. But, this method had some drawbacks: divalent cations were not added while formulating the artificial sweat solution, and diluted solutions were used for creating weakly deposited latent fingerprint. In this study, a method was developed for overcoming the drawbacks of the methods used in the previous study. Several divalent cations were added in this study because the amino acid-ninhydrin (or some of its analogues) complex is known to react with divalent cations to produce a photoluminescent product; and, similarly, the amino acid-1,2-indanedione complex is known to be catalyzed by a small amount of zinc ions to produce a highly photoluminescent product. Also, in this study, a new technique was developed which enables to adjust the intensity when printing the latent fingerprint patterns. In this method, image processing software is used to control the intensity of the master fingerprint patterns, which adjusts the printing intensity of the latent fingerprints. This new method opened the way to produce a more realistic artificial fingerprint in various strengths with one artificial sweat working solution.

This paper presents a computable equilibrium model of an internal market for track resources in a railroad. The problem of estimating the value to each train of track capacity, which in turn is used to create the actual train schedules, is formulated as an N-player, noncooperative game with nondisjoint strategy sets. In this model, the effects of other traffic on a given train schedule (the mean and variance of total travel time) are represented by a line delay model for a scheduled railroad on a partially double track rail line. The generalized Nash equilibrium for the resulting game-theoretic model is found as a solution to a quasi-variational inequality problem. The goal of this model is to ascertain how close the prices from the internal market system (the game-theoretic model) comes to globally optimal prices. Data from a major Class I railroad are used to explore this issue in detail.

Reported herein is the synthesis of a dextran coating on nickel ferrite (Ni-Fe2O4) nanoparticles via chemical coprecipitation. The aqueous solution of the synthesized nanoparticles showed good colloidal stability, and no precipitate was observed 20 months after the synthesis. The coated nanoparticles were found to be cylindrical in shape in the TEM images, and showed a uniform size distribution with an average length and diameter of 17 and 4 nm, respectively. The coated particles were evaluated as potential T1 and T2 contrast agents for MRI. The T1 and T2 relaxations of the hydrogen protons in the water molecules in an aqueous solution of dextran-coated Ni-Fe2O4 nanoparticles were studied. It was found that the T1 relaxivity for the aqueous solution of dextran-coated nanoparticles was slightly greater than that of a commercial Gd-DTPA-BMA contrast agent. The T2 relaxivity, however, was almost twice that of the commercial Gd-DTPA-BMA contrast agent. Animal experimentation also demonstrated that the dextran-coated Ni-Fe2O4 nanoparticles are suitable for use as either T1 or T2 contrast agents in MRI.

Sea ice is a good indicator to monitor the global climate change. Many of previous studies using the satellite observations show a steady decline in Arctic sea ice. The study investigates the characteristics of the averaged surface roughness, and refractive index from March 2003 to July 2011 using the AMSR-E daily data. The surface roughness and refractive index of the sea ice is retrieved using a unique inversion algorithm based on the characteristics of the polarized reflectivities, the Hong approximation, and the incidence angles of the many current passive microwave satellite sensors. The averaged roughness and refractive index show the downward trend and opposite signature with an acceleration, respectively. From the seasonal variations, the averaged roughness and refractive index show the minimum and maximum values in the summer period, respectively. In addition, the annual peaks of two physical parameters exhibit the phase difference of a month. In conclusion, this research provides a physical explanation that the sea ice is melting increasingly using the satellite observation.

Cirrus is important in the energy balance of the earth-atmosphere system. Previous studies are based on the forward models using the single scattering in the cirrus. In this study, we provide a unique method to detect the cirrus using the polarized reflectivities, single-scattering, and optical properties of water and ice with Moderate Resolution Imaging Spectrometer (MODIS) observations. Consequently, the polarized reflectivities at MODIS 1.375 μm channel show the reasonable characteristics of the cirrus. The effective refractive indexes are retrieved approximately from 1.1 to 1.4. This investigation provides an effective inversion procedure for detecting the cirrus using the physical characteristics in the cirrus on the basis of the polarization and refractive index.

This paper presents a model which is aimed at developing an efficient air traffic system for given demand and airport capacity levels by the proper pricing of landing slots. A computable Nash equilibrium model is used in the context of a two-stage, game-theoretic representation of a market mechanism for slot allocation. A variational inequality formulation is then used to solve this oligopolistic air transport market model. The choice of travellers among competing airlines is represented by a logit model. Two models are proposed for pricing of landing slots: one with an exogenously determined allocation, and the second with an endogenous allocation. Each model derives the flight patterns, ticket prices, routes, and carrier choice for passengers, and landing fees. A small example is included to illustrate the properties of the models.

The Curie point of nickel films has been determined by measuring the resistivity as a function of temperature. From these data, we observe the thickness dependence of Curie point shift in these films; that is, the thinner the film is, the larger the shift is. By analyzing the data in the light of finite-size scaling theory, we determine the shift exponent /spl lambda/ to be 0.92/spl plusmn/0.04, not the theoretical value of 1.48. Such a deviation from the theoretical value has also been noted in other papers.

Polarization knowledge is important to detect object characteristics. An approximate relationship between vertically and horizontally polarized reflectivities of specular surfaces is developed and validated using the refractive index datasets of water in the various wavelength ranges at various incidence angles. This study proposes a unique technique to estimate the refractive indexes of a specular surface at a given view angle by the direct inversion of the Fresnel equation and the decomposition of the unpolarized emissivity. The unpolarized emissivity is calculated using the Fresnel equation and the refractive index of water at wavelengths ranging from ultraviolet (200 nm) to microwave (18.75 cm). Consequently, the differences of reflectivity between the Fresnel equations and the Hong approximation are approximately less than 0.001 within the Brewster angles of a material. In addition, the results for refractive index show a reasonable range of retrievals within the Brewster's angle. The imaginary parts of the refractive indexes have larger errors than the real parts, due to the uncertainty of the direct inversion of the Fresnel equation.

Rhabdomyolysis is the consequence of extensive muscle injury with the release of muscle cell constituents into plasma. It can arise from trauma and also from a variety of nontraumatic causes. Trauma, drugs, toxins and infection are the major causes of rhabdomyolysis, but it is rarely associated with metabolic disorders such as severe electrolyte disturbance, diabetic ketoacidosis, hyperosmolar nonketotic coma, hypothyroidism and thyrotoxicosis. There have been several reported cases of metabolic rhabdomyolysis, but panhypopituitarism as a cause has never been identified. We experienced a case of acute rhabdomyolysis associated with panhypopituitarism. Thus, So we report this case with the review of related literature. Metabolic disorder is a rare cause of rhabdomyolysis, but it should always be considered in a patient having and unexplained increased of the creatine kinase concentration (J Kor Soc Endocrinol 20:174～178, 2005).

Kallmann's syndrome is defined as the combination of hypogonadotropic hypogonadism and anosmia/hyposmia. The syndrome is a result of defect in the embryonic migratory pathway of gonadotropin-releasing hormone, which synthesizes neurons and olfactory axons. The hypogonadotropic hypogonadism results due to absence of or incomplete pubertal development and may be associated with anosmia, hyposmia, midline defect (color blindness, cleft-lip, cleft-palate, unilateral renal agenesis, sensorineural deafness), cryptorchidism and skeletal anomaly. Till date in Korea, few cases of Kallmann's syndrome have been reported but there are no available reports on cases of Kallmann's syndrome with unilateral renal aplasia and diabetes mellitus. We handled a case of Kallmann's syndrome associated with unilateral renal agenesis and diabetes mellitus. In the current work, we present a peculiar case as afore mentioned with the review of related literature (J Kor Soc Endocrinol 20:96～102, 2005).