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The decline in genome sequencing costs has widened the population that can afford its cost and has also raised concerns about genetic privacy. Kim et al. present a practical solution to the scenario of secure searching of gene data on a semitrusted business cloud. However, there are three errors in their scheme. We have made three improvements to solve these three errors.(1) They truncate the variation encodings of gene to 21 bits, which causes LPCE error and more than 5% of the entries in the database cannot be queried integrally. We decompose these large encodings by 44 bits and deal with the components, respectively, to avoid LPCE error. (2) We abandon the hash function used in Kim's scheme, which may cause HCE error with a probability of 2 −22 and decompose the position encoding of gene into three parts with the basis 2 11 to avoid HCE error. (3) We analyze the relationship between the parameters and the CCE error and specify the condition that parameters need to satisfy to avoid the CCE error. Experiments show that our scheme can search all entries, and the probability of searching error is reduced to less than 2 −37.4 .

By analyzing the formation causes of the mountain torrent disasters as well as the distribution characteristics of rainstorm in Longmen Mountain area, and citing the typical post-seismic the mountain torrent disasters within 2008~2013 after the Wenchuan earthquake in the area as example, the character of post-seismic floods, the spatial distribution of the devasting post-seismic debris flows, the critical rainfall to trigger the mountain torrent disasters and so on are explored. Besides, the sediment before and after the Wenchuan earthquake of the Minjiang watershed are compared. The conclusions are as following: (1) The time of the post-seismic flash floods and debris flows after the Wenchuan earthquake are centered from July to September, which is consistent with the rainfall of the area. (2) Rather than the debris flows are triggered when the rainfall intensity reached the critical rainfall intensity, those are closely linked with the pre-accumulated rainfall. That is to say, the more pre-accumulated rainfall, the more probability of the debris flows. (3) After the Wenchuan earthquake, the total sediment increases 13.8%~70%. But the increasing range is varied from year to year. In the year when the debris flow occurred, the sediment shall increase drastically.

Xinjiang arid area is characterized by low rainfall, strong evaporation capacity, sparse vegetation, intensive tectonic movement, and fragile ecological environment ; the rainfall-type debris flow in the arid area are obviously different from the same type debris flow in humid and subhumid area of China with conditions of rainfall excitation, watershed morphology, motion and deposition processes, material composition, active period and disaster mechanism. Investigations and analyses of characteristics of rainfall-type debris flow in the arid area will reveal the rule of the occurrence and development and explore the evolution trends, to establish reasonable disaster reduction measures. Qiaoquli gully located in Kashgar is a typical arid area rainfall debris flow gully. The 50-year frequency outbreak of debris flow in 2005 destroyed chinapakistan highway . Further investigation to this debris flow gully will contribute to our understanding of this kind of debris flow disaster characteristics and mechanism.

Cracking development in soils is of significance for their physical and mechanical properties. The fines content in soils is one of the most important factors in cracking development, leading to it being of great importance to quantitatively study how the cracking development is influenced by the fines content. In this paper, experimental simulations on soil surface cracking were first conducted in the lab with soil from Jiangjia Valley. Digital image processing technology was then applied to investigate cracking in soil with different fines content by describing the surface cracks with crack area density Ac (ratio of all cracks’ area to total surface area of the cracked soil) and crack line density Lc (ratio of all cracks’ perimeters to total surface area of the cracked soil). The conclusions are drawn as follows: 1) Surface cracks increase with fines content going up; specifically, when the soil mass with fines content ranging from 20% to 30%, there is a significant increase in cracks; There is no crack developed in the soil with no fines, comparing to the gradual increase in soils with other fines content. 2) With the loss of water content, Ac and Lc will increase until a constant value is reached. However, small cracks will be closed and big ones will evolve into smaller ones if enough water is added. 3) Soil mass with fines content less than 20% is inclined to have small cracks when it is drying and cracks will be closed if enough water is added; on the other hand, soil mass with fines content more than 20% is inclined to have bigger cracks and they will become smaller when submerged into water. 4) After times of wetting and drying cycles, soil mass shrinks and soil dry density increases, which leads to the decrease of Dc and Lc, which suggests soil with larger dry density will probably have fewer cracks.