Table of Content

20 November 2018, Volume 54 Issue 6

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Experimental Study of Kinetic Characteristics for Gid Fin Transmission Mechanism of Reusable Launch Vehicle

WANG Chen, YUAN Wenquan, GUO Yue, ZHANG Hongjian, WANG Xiaojun, SHI Yuhong

2018, 54(6):  1137-1146.  DOI: 10.13209/j.0479-8023.2018.050

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Grid fin translation mechanism is the key actuator of trajectory and attitude control in reentry flight of the reusable launch vehicle. The kinetic characteristic of translation mechanism is investigated experimentally. An experimental device and experimental schemes comprise position test, transient state test and frequency test are set up. The linear displacement of servo piston rod and the angle displacement of rudder shaft are measured by the displacement sensors. Firstly, the cause of linear displacement abrupt change in position test and angle displacement vibration in transient state test is studied. Furthermore, small shaft turning angle frequency test in low, mid and high frequency are tested and the angle displacement signal delay are comparativly analyzed. The clearances in kinematic pairs are considered as the important affecting factor of kinetic characteristic of translation mechanism and its influencing mechanism is preliminarily proposed. The results provide research object and experimental fundament for farther dynamic analysis and optimal design of transmission mechanism.

Noninvasive Repackaging Method Research for Android Supporting Packed Apps

LI Tongxin, HAN Xinhui, JIAN Rong, XIAO Jianguo

2018, 54(6):  1147-1158.  DOI: 10.13209/j.0479-8023.2018.083

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The authors proposed a new Android repackaging method based on Android app characteristics. The new method can repackage apps without decompiling nor modifying the code and also supports packed apps. The method leverages multiple new code injection techniques to attach code to the app. Then, it adds a hook framework to provide capabilities to modify the code behaviors. Finally, the app’s behaviors will be changed during runtime, thus the app is repackaged. A prototype framework is also implemented. The experiments demonstrate that the framework is compatible to different Android platforms and multiple packers. This research has proved that the current packing techniques have some flaws and the method can be used in dynamic code analysis, defense policies deployment and app modification.

Research of Foot Plantar Pressure Scanning System Design Based on Sensor Array

WANG Mo, FAN Zhuochen, MA Hao, PENG Chen, ZHANG Sixu, WANG Xin’an

2018, 54(6):  1159-1165.  DOI: 10.13209/j.0479-8023.2018.072

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In order to improve the accuracy of foot plantar pressure acquisition and reduce the influence on the experimenter’s natural gait during the measurement, the improved design of plantar pressure acquisition system and the optimization of sampling timing are proposed, which can effectively reduce the noise interference introduced by the sensor and the circuit system, and finally realize the sampling measurement of large size (71.9 cm × 33.5 cm) and high spatial resolution (2.8/cm², a total of 6720 sensor units) plantar pressure sensing system with the sampling rate of 100 SPS. The system is used to test in the Department of Rehabilitation in Guangzhou First People’s Hospital. The collection and analysis of foot plantar pressure can be applied to the postoperative gait rehabilitation training, providing effective quantitative data reference for doctors to evaluate the rehabilitation of patients and formulate targeted treatment plans.

Research on Analysis of Arrhythmia Based on pRRx Serials Derived from ECG Signals

LI Ran, WANG Xin’an, ZHAO Tianxia, LIU Yanling, LI Qiuping

2018, 54(6):  1166-1172.  DOI: 10.13209/j.0479-8023.2018.081

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In order to analyze arrhythmia, a noval practical method was proposed. Here the pRRx serials (x ranged from 1 to 100 ms) extracted from ECG data were taken as fundamental signals. There were obvious differences in distribution of the pRRx serials between 20 people with normal arrhythmia (group I) and 20 patients with arrhythmia (group II). By analyzing the linear indexes and nonlinear indexes of pRRx serials, the computed results show that there are significant statistical differences between the two groups. The linear indexes (AVRR, rMSSD, SDSD) are very different (P<0.001). The nonlinear indexes, from the entropy measures (S_dh, S_ph, S_pf) and the fractal dimension measures (D_sf, D_cf, D_vm, D_rms), also maintain apparent differences (P<0.001). Therefore, the proposed pRRx-serial analysis can characterize the linearity and nonlinearity of the cardiac system to some extent, and can be effective in recognizing the arrhythmia and even heart-related diseases.

Further Security Evaluation for Piccolo Structure against Differential and Linear Cryptanalysis

YIN Qing, WANG Nianping

2018, 54(6):  1173-1178.  DOI: 10.13209/j.0479-8023.2018.086

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To evaluate the security of Piccolo structure, the security against differential and linear cryptanalysis is investigated. A new lower bound on number of active round function and active S-boxes for arbitrary round differential characteristics is given. Using the duality between differential characteristics and linear approximations of Piccolo structure, the new lower bound on number of active round function and active S-boxes for arbitrary round linear approximations is also given. The authors prove that these lower bounds cannot be improved.

Impact of Tibetan Plateau on Global Atmospheric Temperature and Water Vapor Distribution

YAO Jie, WEN Qin, SHEN Xingchen, SHAO Xing, YANG Haijun

2018, 54(6):  1179-1185.  DOI: 10.13209/j.0479-8023.2018.085

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The impact of Tibetan Plateau on the global atmospheric temperature and water vapor distribution is studied using a fully coupled climate model CESM. Comprasion of the sensitivity test without the Tibetan topography (NoTibet) and the reference experiment of realistic topography (Real) shows that the northern hemisphere becomes cold and dry in NoTibet, the southern hemisphere is much the same. Specifically, in the high latitudes of the northern hemisphere, there is a strong cooling from the surface to the stratosphere. The surface cooling centre is in the North Atlantic ocean where the mean annual temperature falls by 5ºC. Another cooling centre is at the 100 hPa which falls by 2ºC. The humidity decreases in the North Atlantic and South Asia, but increases in the South Atlantic and East Africa. Due to the reduction of ocean meridional heat transport, the meridional poleward temperature gradient strengthens, leading to the enhancement of the Hadley circulation. Then it enhances atmospheric meridional heat transport, partly compensates for the depressed northward ocean heat transport, and maintains energy balance in the mid-low latitudes of the northern hemisphere; on the other hand, the humidity reduces in the mid-high latitudes, the northern hemisphere becomes cold and dry. The study shows that Tibetan Plateau has a significant impact on the climate in the northern hemisphere, the sphere of influence can reach to the high latitude.

Topography of Upper Mantle Discontinuities Beneath Nazca Plate and Its Surrounding Area Reveals from SS Precursor and Its Tectonic Significance

MA Yuyan, GE Zengxi

2018, 54(6):  1186-1194.  DOI: 10.13209/j.0479-8023.2017.179

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An upper mantle discontinuity topography map of southern Nazca Plate and western South America Plate (120°W?60°W, 30°S?5°N) was obtained by using common mid-point stacking in bins of 5 degree radius over ten thousand USArray teleseismic records. The resolution was higher than that of previous studies because the records more densely sampled the region so that stacking bins were smaller. Discontinuity topography corresponding to high temperature anomalies in deep mantle was observed beneath Galapagos, Easter and San Felix hotspots. Other findings include a depression of 410 km discontinuity beneath Southern East Pacific Rise and depressions of both 410 km and 660 km discontinuities beneath the subduction zone.

Accumulation Process and Control Factors of Jurassic-Cretaceous Distant-Source and Secondary-Filled Reservoirs in the Hinterland of Junggar Basin

MA Weijiao, WEI Yanzhao, LI Xia, TAO Shizhen, LI Yongguang, ZHAO Zhengya

2018, 54(6):  1195-1204.  DOI: 10.13209/j.0479-8023.2018.073

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Homogenization temperature of fluid inclusions, stratigraphic burial-thermal history, paeleostructure of accumulation period, known reservoirs and geochemical index are analyzed. Hydrocarbon accumulation periods, hydrocarbon transport system, trap-forming conditions of the Jurassic-Cretaceous in the hinterland of Junggar Basin are discussed. Thus, the dynamic accumulation process of the distant sourced, secondary-accumulated reservoirs is revealed. Results show that there are two periods of oil and gas charging in the Jurassic and cretaceous reservoirs in the hinterland of Junggar Basin, which are primary reservoirs formed in the early Cretaceous and secondary-filled reservoirs formed in the late paleogene till now. Both the primary reservoirs and sencondary accumulated reservoirs are widely spread in the hinterland area. Faults-sand bodies-unconformities act as three dimensional transporting systems for hydrocarbon migration and accumulation. The formation of primary reservoirs is controlled by paleostructure of accumulation period. During the later dissolution of paleostructure, primary reservoirs are destroyed and oil and gas migrate towards the north. Reservoirs types are decided by trap conditions on the migration pathways. At present, low-amplitude anticline, fault block and litho-stratigraphic reservoirs are the most discovered.

MSWD and n Value in Laser Ablation ⁴⁰Ar/³⁹Ar Isochron Dating for Young Volcanic Rocks

HU Yan, JI Jianqing, ZHOU Jing, TU Jiyao

2018, 54(6):  1205-1215.  DOI: 10.13209/j.0479-8023.2018.090

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The laser ablation ⁴⁰Ar/³⁹Ar method makes it possible to date quanterary volcanic rocks precisely. So far, it lacks an assessment criterion that can be used to estimate the reliability of test data and geochronological information. The mean square weighted deviation (MSWD) and the number of measurement (n value) are used to be the crucial parameter to evaluate sample properties and experimental standard. When applying laser ablation ⁴⁰Ar/³⁹Ar method to date young volcanic rocks, a best-fit ⁴⁰Ar/³⁹Ar isochron diagram requires isotopic homogeneity of the sample and permanent closure of the isotope system at the same time. While MSWD, which is related to n value, is a parameter to determine whether the data are located in the same normal distribution, or in other words, whether the sample has a unified true age, it is applicable to use MSWD and n value to estimate the level of confidence placed on the computed mean. The critical values of MSWD for the 99.7% confidence interval using differing degrees of freedom are calculated in this paper. It is important to note that MSWD is available in evaluating dating result of both apparent and isochron ages. For the samples which tend to have heterogeneous initial ⁴⁰Ar/³⁶Ar ratios or different closure times, MSWD combined with the probability density of apparent ages can be used to distinguish different groups of samples, calculate the isochron ages respectively, and interpret the result after accounting for the various parameters to evaluate the data quality.

Sand Veins Grown in Yuanmou Fault and its Implications of Fault Activity

LU Haifeng, TANG Yongzhong

2018, 54(6):  1216-1226.  DOI: 10.13209/j.0479-8023.2018.080

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The sand veins in Yuanmou fault zone have been investigated in the work, and its tectonic implications has been defined. The result shows that the sand veins generally develop in the surface or sub-surface rock straum in the middle-north segment of Yuanmou fault, and extends parallelly along the fault with larger dip angles. In addition, the patterns and structures of the sand veins and its relationship of the host rocks show that the sand veins were filled with the stretchable fracture from the overlying strata as the result of the sand liquefaction from the main fault plane or secondary fault pane which were connected with Yuanmou fault was intensively active, or due to the strong earthquake. Moreover, the thermoluminescence (TL) and optically stimulated luminescence (OSL) dating show that the sand veins were formed about 7 kaBP, indicating a intensive activity of Yuanmou fault during the Late Quaternary.

Efficient Traffic Flow Data Processing Method and Its Application Based on Spark Framework

LI Xin

2018, 54(6):  1227-1234.  DOI: 10.13209/j.0479-8023.2018.070

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A traffic flow data processing and forecasting framework based on Spark is designed, and it can complete the efficient cleaning, statistics, storage and query of traffic flow data. A multi-order spatial weight matrix STARIMA model is used to predict the traffic flow, and it can verify the efficiency of data processing and the support for the prediction. By comparative experiments, the results show that the traffic flow data processing framework is efficient, and it is suitable for realizing complex data cleaning and mining algorithms and establishing data support for the prediction model. The traffic flow prediction model optimizes the multi-order spatial weight matrix, and it takes both efficiency and accuracy into consideration. The prediction results can provide reference for traffic guidance.

An Improved Map Matching Algorithm Based on HMM Model

LIU Min, LI Mei, XU Xiaoyu, MAO Shanjun

2018, 54(6):  1235-1241.  DOI: 10.13209/j.0479-8023.2018.038

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For it’s difficult to guarantee the accuracy and time efficiency of online map matching simultaneously, an improved online map matching algorithm based on the HMM model is proposed. Different from other global or local algorithms, the algorithm introduces reliable point to divide the trajectory, thus reducing the calculation of transition probability and the output delay of matching results. Also, the method of calculating the transmitting probability by combining distance factor and directional factor is proposed. The algorithm is verified using floating car trajectory data in Seattle. Experimental results show that the proposed algorithm outperforms the traditional HMM map matching algorithm both in accuray and time efficiency, which can meet the requirement of online map matching.

A Homogenous Pixel-Weighted Interferometric Phase Filtering Method for Time-series InSAR

HUANG Junsong, ZENG Qiming, JIAO Jian, GAO Sheng

2018, 54(6):  1242-1250.  DOI: 10.13209/j.0479-8023.2018.032

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In order to effectively use the temporal information of multi-temporal InSAR and ensure the homogeneity of pixels in the window, a homogenous pixels-weighted interferometric phase filtering method is proposed. The method firstly uses the goodness-of-fit test to identify the statistically homogenous pixels (SHP) in the multi-temporal SAR images, and then the weighted interferometric phase filtering is performed just within those SHP, which ensures that the central pixels is not affected by the surrounding heterogeneous pixels. The experimental results based on real SAR interferograms show that compared with classic Goldstein filter and Lee filter, the proposed filter has advantages in visual effect, phase residues reduction, and phase derivative standard deviation, and achieves the original intention of the design of this filter.

Application of Himawari-8 Data in Monitoring Forest Fire

DU Pin, LIU Mingxu, XU Tingting, SONG Yu

2018, 54(6):  1251-1258.  DOI: 10.13209/j.0479-8023.2018.082

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Taking the forest fire in Sumatra, Indonesia on October 15, 2015 as an example, method to extract forest fire hotspots using the new-generation geostationary satellite―Himawari-8 data was explored via clear sky analysis, potential fire pixel identification, sunglint test and background analysis. Within the temporal and spatial range of this study, 10109 Himawari-8 hotspots were extracted in all (142 significant instants), and the maximum number of hotspots for a single moment was 267 (03:40LT). Through quantitative comparison of time-space distributions, it was found that compared with MODIS hotspots, hotspots derived from Himawari-8 data were of smaller amount and more dispersed spatial distribution. However, two kinds of hotspots were very similar in overall spatial distribution. The characteristics of spatial distribution and quantity of Himawari-8 hotspots were consistent with fire information reflected by the true-color image of Himawari-8. In general, extracted Himawari-8 hotspots could well reflect the information of forest fire and provide useful information in forest fire mornitoring.

Research on “Resource Curse” Effect and Transmission Mechanism in Resource-based Cities: A Case of 36 Cities in Central China

WANG Jiayi, CUI Nana

2018, 54(6):  1259-1266.  DOI: 10.13209/j.0479-8023.2018.076

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With Eviews8, using the OLS model, individual fixed effect model, time fixed effect model and individual-time fixed effect model, “resource curse” effect and transmission mechanism are analyzed in 36 resource-based cities in central China. The results show that individual-time fixed effect model is the best. In the individual-time fixed effect model, the regression coefficient of resource dependence is negative and it’s significant at 5% level, which proves that “resource curse” effect really exists. Resource dependence has a negative impact on manufacturing investment at 1% significant level. Manufacturing investment has a positive effect on the actual GDP per capita at 5% significant level. In conclusion, the main transmission mechanism of “resource curse” effect is crowding out effect of manufacturing industry. In the transformation and development of resource-based cities, more attention should be paid to attract manufacturing investment, reduce the government's intervention in the microeconomic field, and build a diversified industrial system to realize the sustainable development of economic society.

Treatment and Reuse of Highly Concentrated Cutting Fluid Wastewater by Decompression-Dehydration-Drying System

FAN Yi, ZOU Zhendong, LI Ruili, WU Xiaofang, QIU Guoyu, NAKAMURA Kazuhiko, GAO Jian

2018, 54(6):  1267-1275.  DOI: 10.13209/j.0479-8023.2018.069

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A decompression-dehydration-drying system was designed and improved to deal with cutting fluid wastewater produced during metal processing. The results show that the removal rate of total suspended solids is more than 99.38%, and the average removal rates of n-HEX, BOD5, COD_Mn, total nitrogen, total phosphorus, copper and zinc are 99.07%, 96.67%, 98.64%, 81.28%, 99.33%, 98.69% and 99.79% respectively. Combined with ozone treatment it can further improve the removal rate of organic pollutants. Compared with other treatment methods, during the process of sewage treatment, the proposed system produces very little smell and noises, and do not need a large number of chemical agents, and has a small footprint and low cost. It is especially fit for the treatment of highly concentrated cutting fluid wastewater.

Identification of an Aerobic Denitrifier and Its Denitrification Characteristics

LI Xue, LIU Sitong, CHEN Qian

2018, 54(6):  1276-1282.  DOI: 10.13209/j.0479-8023.2018.071

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Strain HG-7 was identified as Pseudomonas sp. through 16s rRNA gene sequence analysis. The aerobic denitrification ability of strain HG-7 was further proved by the existence of the napA and nirK genes. Further studies showed that the optimal carbon resources for strain HG-7 were sodium acetate and sodium succinate, the optimal C/N ratio was 6−10, and the suitable temperature was 26−30℃. At this condition, with an initial nitrate nitrogen of 100 mg/L, 98% of nitrate could be removed in 48 hours and the amount of nitrite accumulation was very small. Moreover, with nitrite as the sole nitrogen source, 100% of nitrite could be removed at lower nitrite concentration. But the nitrite nitrogen removal rate was about 40% when the nitrite concentration increased to 91.4 mg/L, indicating that high nitrite concentration was harmful for aerobic denitrification by strain HG-7. The strain HG-7 has great potential to be used for biological nitrogen removal, which was particularly significant for actual wastewater treatment processes.

An Approach Based on Euler’s Formula to Estimating Gini Coefficient of Pareto Distribution

CHEN Yanguang

2018, 54(6):  1283-1289.  DOI: 10.13209/j.0479-8023.2018.052

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A simple approach to estimating Gini coefficient based on Lorenz curve is proposed to solve the problem that the concentration index replacing the Gini coefficient results in deviation from imbalance measurement of spatial distributions and size distributions. In view of the scale-free distribution phenomena in the complex social and economic system, a logarithmic function of convex Lorenz curve is derived from the pure Zipf’s distribution by means of Euler’s formula for the sum of harmonic sequence. Then an approximate formula to estimate Gini coefficient can be constructed by using the parameters of the logarithmic Lorenz curve model. The formula is applied to the cities in Beijing, Tianjin and Hebei (Jing-Jin-Ji) region, and the Gini coefficients of 22 years are evaluated by the night lighting data. The results show that there is a significant difference between the Gini coefficient and the centralization index. A conclusion can be reached that the centralization index is applicable to the distributions with characteristic scales, while the proposed formula are suitable for the scale-free distributions. This work will help researchers to understand the scopes of application of the imbalance measurements and provide a reference for further developing the direct estimation methods of Gini coefficient.

Jobs-Housing Balance Comparative Analyses with the LBS Data: A Case Study of Beijing

ZHAO Pengjun, CAO Yushu

2018, 54(6):  1290-1302.  DOI: 10.13209/j.0479-8023.2018.077

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Measuring job-housing balance is an important part of job-housing related research, and the dataset applied in previous researches is expanded from survey and census data to LBS data. However, current research lacks comparative studies between different data sources. Beijing urban area is taken as an example to measure and analyze job-housing balance spatial-temporally from different aspects, using different kinds of LBS data, which including heatmap data, Point-of-interest data and Weibo-checkin data. This could provide decision-making reference to improve the job-housing balance. The authors compare the differences in the results of LBS data with the traditional population and economic census data, discusses the causes of the differences, and provides suggestions for further improving the research of LBS data in job-housing relations.

Environmental Satisfaction and Environmentally Responsible Behavior Research: A Case Study on Shenzhen Coastal Ecological Park

WANG Zhuoqun, MEI Fengqiao

2018, 54(6):  1303-1310.  DOI: 10.13209/j.0479-8023.2018.084

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Choosing Shenzhen Coastal Ecological Park as a case location, the paper measured the environmental satisfaction and environment responsible behavior (ERB) of interviewees through questionnaire survey and the auxiliary interview. The “importance-performance” analysis (IPA) method was used to detect the interviewees’ environmental satisfaction of the Coastal Ecological Park. Fourteen environmental-related factors were finally divided into four different quadrants, and the authors put forward improved strategy according to them. Age had a significant difference impact on the interviewees’ ERB, and the type of gender, the level of education, the type of occupation, the average monthly income level and the number of times for revisiting didn’t have significant difference impact. There was a positive correlation between environmental satisfaction and environmental responsible behavior. Visitors have a certain awareness of environment protection, but the overall level of environmenttal responsible behavior was not high, and visitor was also lack of active participation in maintaining environment. Based on the analysis results, the pertinent suggestions are proposed to promote the recreational management and protect the environment of the destination.

Spatiotemporal Dynamics of Soil Extracellular Enzyme Activity and Its Influence on Potential Mineralization Rate of Soil Organic Carbon in Forests of Daxing’an Mountain Range

ZUO Yiping, ZHANG Xinyue, ZENG Hui, WANG Wei

2018, 54(6):  1311-1324.  DOI: 10.13209/j.0479-8023.2018.089

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In order to explore spatiotemporal dynamics of soil extracellular enzyme activity (EEA) and its influence on potential mineralization rate of soil organic carbon (SOC) of the Daxing’an Mountain range, soil samples of three forests (Pinus sylvestris forest; Birch forest; Larch pine forest) and three ground cover plants in Larch forest (Grass; Ledum; Moss) were collected from Daxing’an Mountain range in summer and winter. Activities of six enzymes including carbon- (C) (β-1,4-glucosidase, β-1,4-xylosidase, β-D-cellobiohydrolase), nitrogen- (N) (N-acetyl-β-glucosaminidase, leucine aminopeptidase) and phosphorus- (P) (acid phosphatase) acquisition, potential mineralization rate of SOC and main environmental factors were analyzed and potential driving mechanisms were explored. Results showed that Both Pinus sylvestris forest and Birch forest exhibited significant higher activities of enzyme C, N and P in summer, however, Larch forest showed contrary seasonal dynamic with soil EEA of moss soil significantly higher in winter. From summer to winter, soils of three forests and three ground cover plants all experienced reduced P vs. N limitation. Besides, soils of Pinus sylvestris forest and Birch forest both experienced increased C vs. nutrient limitation, however, Larch forest showed contrary seasonal dynamics with the existence of moss. In Pinus sylvestris forest and Larch forest, potential mineralization rate of SOC exhibited higher in winter while Birch forest showed contrary trend. Analysis showed that potential mineralization rate of SOC was influenced by enzyme C and enzyme N significantly, whereas little influenced by enzyme P. C vs. nutrient limitation had little correlation while P vs. N limitation had significant negative correlation with potential carbon mineralization rate.

How Urban Built Environment Affects the Use of Public Bicycles: A Case Study of Nanshan District of Shenzhen

SUN Yiling, TONG De, CAO Chao

2018, 54(6):  1325-1331.  DOI: 10.13209/j.0479-8023.2018.078

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With the aid of spatial lag model, the influence mechanism of spatial factors around public bicycle stations (PBS) is examined at the research scope of 500 m buffer zone of 363 PBS, based on the trip data from the public bicycle system in Nanshan District of Shenzhen. Factors are selected including the location of PBS, surrounding public transportation, riding infrastructure, built environment and self-correlation of adjacent stations. The research focus on the impact of different land use types where different people gather. It is found that PBS with more bus lines, more road area, longer branch road, more industrial, low-grade commercial, low-grade housing building area around has more usage at the peak time of the workdays, while PBS far away from metro station with longer of green road has less usage. The research also shows that there is a high spatial autocorrelation between different PBS. The conclusion suggests that the public bike station planning pay more attention to the surrounding environmental factors of PBS, take full account of commuting and other regular needs in the distribution and pricing of public bicycles to increase the supply in low-income population agglomeration areas combing with the characteristics of population distribution.

Synthesis and Photocatalytic Property of TiO₂ Photocatalysts Using Hydrochars as Template

WANG Xiaojing, ZHANG Qiming, LIU Yangsheng

2018, 54(6):  1332-1338.  DOI: 10.13209/j.0479-8023.2018.088

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Using hydrochars as template, TiO₂ photocatalysts were prepared by the sol-gel method. The samples were characterized with X-ray diffraction (XRD), Fourier infrared spectrum (FT-IR), scanning electron microscope (SEM) and BET specific surface area measurement. The photocatalytic activity was investigated by degradation of methyl orange (MO) as target pollutant in the solution. The results showed that HTC-TiO₂ remained anatase type at high calcination temperature due to the higher thermal stability than TiO₂. The TiO2 particles were almost uniformly dispersed on the surface of HTC. HTC-TiO₂ had smaller crystal sizes, bigger specific surface area and the flake structure, which had the same structure character as the hydrochars micro-structure and was beneficial to improve the photocatalytic activity. The degradation rate of MO under 550 W iodine-tungsten lamp illumination for 2 hours was 40.6% in presence of HTC-TiO₂ calcined at 450ºC, which increased by 1.5 times more than those in presence of TiO₂ (16.2%).

Predicting Mechanism of Self-Esteem on Meaning in Life: Mediating Effect of Locus of Control and Positive Emotion

LIU Zhixiao, WU Rengang

2018, 54(6):  1339-1345.  DOI: 10.13209/j.0479-8023.2018.079

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Based on previous finding that self-esteem predicts meaning in life, this study introduced locus of control and positive emotion as mediators, aiming to explore the predicting mechanism of self-esteem on meaning in life from cognitive and emotional perspective. Self-esteem, locus of control, positive emotion and meaning in life of all the participants were measured by Self-esteem Scale, Locus of Control of Behavior Scale, Positive Affect and Negative Affect Scale, Meaning in Life Questionnaire before the experiment. Then expressive writing intervention was performed to manipulate the participants’ level of self-esteem. At last, all the participants finished the measurement of locus of control, positive emotion and meaning in life again. Repeated measure ANOVA was performed to test the effect of experimental manipulation of self-esteem on locus of control, positive emotion and meaning in life, and hierarchical multiple regression and Boostrap were utilized to test the mediating effect of locus of control and positive emotion on self-esteem and meaning in life. The result indicated that experimental manipulation of self-esteem could significantly affect locus of control, positive emotion and meaning in life. Furthermore, positive emotion and locus of control were mediators between self-esteem and meaning in life.

Analysis of Water Resources and Energy Security in Shenzhen Based on Factor Analysis Method

CAO Ye, ZOU Zhendong, CHEN Wenlei, ZHUO Jinxin, QIU Guoyu

2018, 54(6):  1346-1350.  DOI: 10.13209/j.0479-8023.2018.087

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The factor analysis of water resources and energy security in Shenzhen in 1996–2015 was carried out. Economic and average factor (f₁), population and elasticity factor (f₂) are two main factors. f₁ shows the threat of supporting the city’s normal operation to water resources and energy security, with a weight of 68%. f₂ shows the uncertainty brought about by the increments of economic and population to water energy system safety, with a weight of 32%. The composite score shows that the total water energy system safety in Shenzhen tends to decline. This conclusion accords with the actual situation of water energy system in Shenzhen municipality. It shows that the evaluation model is effective for the analysis of water energy security situation in Shenzhen, and can provide reference for the decision-making of Shenzhen municipality.

Design and Implementation of an Asynchronous Low Power RSA Circuit Structure

ZHANG Qihui, CAO Jian, CAO Xixin, YU Dunshan, ZHANG Xing

2018, 54(6):  1351-1354.  DOI: 10.13209/j.0479-8023.2018.046

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An asynchronous low power RSA circuit structure and its modular multiplication circuit structure for smart cards and RFID tags are proposed. By using GTECH optimization scheme and BrzCallMux implementation strategy, ASIC implementation is carried out based on a TSMC 130 nm standard CMOS technology. Experimental results show that the area of the proposed asynchronous low power RSA is only 4% of that of another asynchronous RSA, its average time to perform a cryptographic operation is only 0.216% of that of another asynchronous RSA, and its power consumption is only 16.99% of that of its corresponding synchronous counterpart.