Calibration chain design based on integrating sphere transfer radiometer for SI-traceable on-orbit spectral radiometric calibration and its uncertainty analysis

In order to satisfy the requirement of SI-traceable on-orbit absolute radiation calibration transfer with high accuracy for satellite remote sensors,a transfer chain consisting of a fiber coupling monochromator（FBM） and an integrating sphere transfer radiometer（ISTR） was designed in this paper.Depending on the Sun,this chain based on detectors provides precise spectral radiometric calibration and measurement to spectrometers in the reflective solar band（RSB） covering 300–2500 nm with a spectral bandwidth of 0.5–6 nm.It shortens the traditional chain based on lamp source and reduces the calibration uncertainty from 5% to 0.5% by using the cryogenic radiometer in space as a radiometric benchmark and trap detectors as secondary standard.This paper also gives a detailed uncertainty budget with reasonable distribution of each impact factor,including the weak spectral signal measurement with uncertainty of 0.28%.According to the peculiar design and comprehensive uncertainty analysis,it illustrates that the spectral radiance measurement uncertainty of the ISTR system can reach to 0.48%.The result satisfies the requirements of SI-traceable on-orbit calibration and has wider significance for expanding the application of the remote sensing data with high-quality.

Dick Effect in the Integrating Sphere Cold Atom Clock

The Dick effect is an important factor limiting the frequency stability of sequentially-operating atomic frequency standards. Here we study the impact of the Dick effect in the integrating sphere cold atom clock （ISCAC）. To reduce the impact of the Dick effect, a 5 MHz local oscillator with ultra-low phase noise is selected and a new microwave synthesizer is built in-house. Consequently, the phase noise of microwave signal is optimized. The contribution of the Dick effect is reduced to 2.5× 10^-13τ-1/2 （3- is the integrating time）. The frequency stability of 4.6 × 10-13τ-1/2 is achieved. The development of this optimization can promote the space applications of the compact ISCA C.

Reaching a few 10-15 long-term stability of integrating sphere cold atom clock

We present the long-term stability of the integrating sphere cold atom clock（ISCAC） and analyze its systematic limitations. The relative frequency instability of 2.6 × 10-15 is reached for an averaging time of 2 ×105 s. The second-order Zeeman effect and the cavity pulling effect in ISCAC, which would induce the frequency drift from the clock transition, are analyzed. The analytical and experimental results indicate that the cavity pulling effect is the main contribution to the long-term frequency instability of the ISCAC. Further technical improvements to the microwave cavity are also discussed.

Development of an integrating sphere calibration method for Cimel sunphotometers in China aerosol remote sensing network

Based on the integrating sphere traced from the National Institute of Standards and Technology （NIST, USA）, a sphere calibration method and protocol for the China aerosol remote sensing network （CARSNET） Cimel sun photometer was established. Four CE318 sun photometers were verified using the proposed cal- ibration method and operational protocol. The calibration results showed that the instrument coefficients differed by less than 3% for visible （-5% for infrared） wavelengths from the original ones stated by Cimel Electronique. In situ validation experiment data showed that radiances at ±6° measured by sun collimator （aureole） were consistent with those measured by sky collimator （sky）, under both almucantar （ALMUC） and principal plane （PPLAN） scenarios. Differences at all wavelengths were less than 1%, indicating that the method and protocol are suitable for CARSNET field sun photometer calibration, and would benefit improvement of data quality and accuracy of network observations.

Effect of light beam on measurements of reflectance and transmittance of turbid media with integrating sphere： Monte Carlo simulation

Integrating sphere technique is widely used to measure the total reflectance and transmittance of turbid sample, but the unavoidable light loss induces some measuring error. It has never been reported whether the error depends on the shape and size of light beam. In this paper, a convolution for computing the responses to rectangular incident light beam based on the Monte Carlo method was presented. The effects of light beam shape and size, and optical properties of sample on the measurements were addressed. The results show that the light loss with rectangular incident light beam is larger than that with circular one with the same area. The more the area of light beam, the more the light loss. And the light loss induced by the optical properties of sample is much more significant than that by the shape and size of the incident light beam.

Interrelations With Forms of Corruption in the Political Sphere and Its Causal Conditions in Mongolia (the Final Part)

Corruption,which is a serious problem for us today,covers a wide range of social and political phenomena and processes,from the normal functioning of ordinary citizens to the forms and structures of political governance.In particular,the personality is determined by the way of life,the environment,and the needs of the family and social group,and then a political ideology is formed based on the multifaceted interests of social groups,which are expressed in complex social,economic,and political forms.Indicators of the extent to which social well-being is achieved in developing democracies raise questions about whether citizens are united in their views and actions,as well as how they participate and are interested in social and political activities.On the other hand,this is reflected in the differences in views and the level of trust in the government and other social institutions,and as an important tool for determining the development of the country.It is necessary to determine the level of social and political participation.This is the root cause of the problem.Because every democracy is very different,to understand how they affect human development,and to be a social person,people need to be able to provide a little economic security and an understanding of the issues at stake.This is the basis for building a transparent society based on the principles of zero tolerance for corruption,justice,equal participation,and equality.That is why in this subsection we explore the relationships between political parties,groups,political,business,and criminal groups in the form of political corruption,as well as the causes of political corruption in the political sphere.

Different Optical Properties between Human Hepatocellular Carcinoma Tissues and Non-tumorous Hepatic Tissues In Vitro

There has been an ongoing search for clinically acceptable methods for the accurate,efficient and simple diagnosis and prognosis of hepatocellular carcinoma（HCC）.Optical spectroscopy is a technique with potential clinical applications to diagnose cancer diseases.The purpose of this study was to obtain the optical properties of HCC tissues and non-tumorous hepatic tissues and identify the difference between them.A total of 55 tissue samples（HCC tissue,n=38;non-tumorous hepatic tissue,n=17） were surgically resected from patients with HCC.The optical parameters were measured in 10-nm steps using single-integrating-sphere system in the wavelength range of 400 to 1800 nm.It was found that the optical properties and their differences varied with the wavelength for the HCC tissue and the non-tumorous hepatic tissue in the entire wavelength range of research.The absorption coefficient of the HCC tissue（1.48±0.99,1.46±0.88,0.86±0.61,2.15±0.53,0.54±0.10,0.79±0.15 mm-1） was significantly lower than that of the non-tumorous hepatic tissue（2.79±1.73,3.13±1.47,3.06±2.79,2.57±0.55,0.62±0.10,0.93±0.16 mm-1） at wavelengths of 400,410,450,1450,1660 and 1800 nm,respectively（P0.05）.The reduced scattering coefficient of HCC tissue（5.28±1.70,4.91±1.54,1.26±0.35 mm-1） and non-tumorous hepatic tissue（8.14±3.70,9.27±3.08,2.55±0.57 mm-1） was significantly different at 460,500 and 1800 nm respectively（P0.05）.These results show different pathologic liver tissues have different optical properties.It provides a better understanding of the relationship between optical parameters and physiological characteristics in human liver tissues.And it would be very useful for developing a non-invasive,real-time,simple and efficient way for medical management of HCC in the future.

Laser speckle contrast imaging for monitoring of acutepancreatitis at ischemia-reperfusion injury of thepancreas in rats

The influence of ischemia-reperfusion(I/R)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Additionally,the optical properties in norm and under condition of AP in rats were assessed using a modied integrating sphere spectrometer and inverse Monte Carlo(IMC)software.The results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are presented.The data obtained conrm the fact that local ischemia and changes in the blood°ow velocity of the main vessels cause and provoke acute pancreatitis.

A SIMPLE METHOD FOR PREDICTION OF THE REDUCED SCATTERING COEFFICIENT IN TISSUE-SIMULATING PHANTOMS

This paper proposes a method for predicting the reduced scattering coefficients of tissuesimulating phantoms or the desired amount of scatters for producing phantoms according to Mie scattering theory without measurements with other instruments.The concentration of the scatters TiO2 particles is determined according to Mie theory calculation and added to transparent host epoxy resin to produce phantoms with different reduced scattering coefficients.Black India Ink is added to alter the absorption coefficients of the phantoms.The reduced scattering coefficients of phantoms are measured with single integrating sphere system.The results show that the measurements are in direct proportion to the concentration of TiO2 and have identical with Mie theory calculation at multiple wavelengths.The method proposed can accurately determine the concentration of scatters in the phantoms to ensure the phantoms are qualified with desired reduced scattering coefficients at specified wavelength.This investigation should be possible to manufacture the phantom simply in reasonably accurate for evaluation of biomedical optical imaging systems.

A Dialectic Analysis of the Concept of Ecological Civilization

Ecological civilization has already evolved into a complex conceptual system. The mainstream idea holds that ecological civilization is an element of civilization, or a whole new social form, while other ideas view it as a philosophy of green development, a measure of green orientation, an outcome of the overall development of civilization. This paper, however, maintains that ecological civilization is another domain of civilization parallel with social civilization, and an integral whole made up of four elements of civilization. As a domain of civilization, ecological civilization is constant and systematic in content, limited in connotation, and holds a fundamental value. The five–sphere integrated plan(economic, political, cultural, social and ecological progress) will combine the construction of the four elements of civilization and push forward the construction of an ecological civilization.

Effect of purification,dehydration,and coagulation processes on the optical parameters of biological tissues

In this study,the effects of purification,dehydration,and coagulation processes on the absorption and reduced scattering coefficients of chicken liver tissues have been investigated by using a single integrating sphere system.The purification process performed on the tissue samples to remove blood residue has been found to cause a slight change in the optical parameters.Although the dehydration process brings about an increase in the absorption coefficient due to the water loss,no direct relationship has been observed between the reduced scattering coefficient and the dehydration level of the tissue.In addition,it has been observed that there was a relatively small increase in the absorption coefficient and a significant increase in the reduced scattering coefficient after the coagulation process.Therefore,it can be said that the optical penetration depth decreased significantly after dehydration and coagulation processes unlike blood purification.Moreover,fluence rate distributions inside the fresh,blood purified,dehydrated,and coagulated tissue models have been investigated by using the Monte Carlo modeling of photon transport in multilayered tissues simulation code.