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Debugging, albeit useful for software development, is also a double-edge sword since it could also be exploited by malicious attackers. This paper analyzes the prevailing debuggers and classifies them into 4 categories based on the debugging mechanism. Furthermore, as an opposite, we list 13 typical anti-debugging strategies adopted in Windows. These methods intercept specific execution points which expose the diagnostic behavior of debuggers.

Cherenkov radiation is used to study the production of particles during collisions, cosmic rays detections and distinguishing between different types of neutrinos and electrons. The optical properties of water are very important to the research of Cherenkov Effect. Lambert-beer law is a method to study the attenuation of light through medium. In this paper, optical properties of water are investigated by use of a water attenuation performance test system. The system is composed of the light-emitting diode (LED) light source and the photon receiver models. The LED light source model provides a pulse light signal which frequency is 1 kHz and width is 100ns. In photon receiver model, a high sensitivity photomultiplier tube (PMT) is used to detect the photons across the water. Because the output voltage amplitude of PMT is weak which is from 80mv to 120mV, a low noise pre-amplifier is used to improve the detector precise. An effective detector maximum time window of PMT is 100ns for a long lifetime, so a peak holder circuit is used to hold the maximum peak amplitude of PMT for the induced photons signal before the digitalization. In order to reduce the noise of peak holder, a multi-pulse integration is used before the sampling of analog to digital converter. At last, the detector of photons from the light source to the PMT across the water is synchronized to the pulse width of the LED. In order to calculate the attenuation coefficient and attenuation length of water precisely, the attenuation properties of air-to-water boundary is considered in the calculation.

Deep space life exploration nowadays mainly focuses on whether environments on other planets are suitable for the existence of life. This has not hit the key point. As life depending on its specified conditions, it is of great necessity and importance to conduct exploration in the life's original environment. An idea was put forward in this paper to detect specific life forms in the original environment if they exist. This idea, based on fluorescence, included light source unit and detection unit. The former was optical fiber coupled LED and lens; the latter was charge coupled device (CCD) and other lens. Light from LED was collected and transferred by optical fiber, then purified by a filter in order to obtain specific wavelength light, which could excite corresponding organic biological molecules. These molecules emitted light of other wavelength, usually referred to as fluorescence, the moment they were illuminated by excitation light. The fluorescence was also purified by another filter. Then lens was used to collect the light. As to detection device, CCD would give fluorescence image. Theoretical analysis demonstrated that the system could meet the task's requirements. During test in laboratory, this system performed well, too. CCD could output desired signals. This provided strong support that the idea present in the paper is feasible and is of practical significance.

SiO2films have been widely applied in the production of electronic devices, integrated devices, optical thin film devices, sensors because of their desirable properties, such as good insulation, high light transmittance, strong corrosion resistance, good dielectric properties, etc. Amorphous silicon dioxide was fabricated by plasma enhanced chemical deposition on GaAs substrate. The thickness and refractive index are obtained by optical transmittance of the film, which are measured by ellipsometer. The deposition rate of the film and the refractive index are studied at different time, pressure, and the ratio of SiH4/N2O. The SiO2thin film growth rate remained basically unchanged versus time. The reaction chamber pressure, which make the SiO2thin film growth rate getting the peak, should be about 105Pa. But the SiO2thin film growth rate and the refractive index are anti-related. The enormous changes of the gas flow rate do not have huge impact to the response rate. However, the refractive index of SiO2thin film changed greatly when the SiH4flow increased the refractive index of the thin films is highest when the ratio of SiH4/N2O is 200:20