Crime concentrations and similarities in spatial crime patterns in a Brazilian context

Research within the geography of crime and spatial criminology literature most often show that crime is highly concentrated in particular places. Moreover, a subset of this literature has shown that the spatial patterns of these concentrations are different across crime types. This raises questions regarding the appropriateness of aggregating crime types (property and violent crime, for example) when the underlying spatial pattern is of interest. In this paper, using crime data from Campinas, Brazil, we investigate the crime concentrations and the similarities among different crime types across space. Similar to some recent research in another context, we find that crime is highly concentrated in Campinas but the ability to aggregate similar crime types at the street segment level is not generalizability when compared to a North American context.     

A set-up converter and energy transfer system of an “Energy-2” generator for electromagnetic sounding and monitoring of zones of earthquake sources

A boost converter and a system of energy transfer at a high voltage (up to 1100 V) developed for an “Energy-2” generator 200 kW in power are described. This generator is intended for solving the problems of precision monitoring of the electromagnetic depth of the Earth’s crust at seismoactive regions with an aim to search for earthquake forerunners. High voltage allows taking off the total generator’s power on transmitting antennas with high resistance (7 Ω and higher) within a wide frequency range (0.1–200 Hz) as well as on low-resistance antennas (lower than 0.7 Ω) at high frequencies (greater than 20 Hz). Modern Russian and foreign literature on the problem of developing transformers and rectifiers of the generator’s power circuit, responsible for generation of powerful low-frequency electromagnetic signals, is reviewed. Theoretical research and numerical simulation of the “Energy-2” generator’s power circuit are performed and the element base of the latter is optimized. Based on the developed documentation of all components, radiators and a system of forced ventilation have been made. The proposed generator-measuring complex has no analogs in world practice and can be used for solving a wide range of fundamental and applied problems. Original Russian Text ? E.D. Tereshchenko, V.F. Grigoryev, M.B. Barannik, A.N. Danilin, B.V. Efimov, V.V. Kolobov, P.I. Prokopchuk, V.N. Selivanov, Yu.A. Kopytenko, A.A. Zhamaletdinov, 2009, published in Seismicheskie Pribory, 2009, No. 4, pp. 43–65.     

风电机组对测震台站观测影响的实验研究

为了在测震台址勘选中对规避风电机组这类新生的常见干扰源有定量参考依据,以减少盲目性,提高台址勘选效率,在野外开展了定量实验,取得了实地测试数据,并初步探讨了风电机组干扰源的振动衰减关系。研究认为,对于风电机组这类干扰源,测震基岩固定台站Ⅰ级环境地噪声水平的建议规避距离为800 m。     

基于2-by-n细胞自动机的伪随机序列发生方法研究

随机序列在密码学中有着广泛的应用,其产生方法已经成为密码学的重要研究课题。首先介绍了细胞自动机的基本概念,并详细介绍了2-by-n CA的规则及最大周期CA。最后基于2-by-n CA的特点提出了二维梯形伪随机序列发生方法。计算机模拟表明,基于2-by-n CA的二维梯形伪随机序列发生器具有结构简单、高速、周期长的特点,产生的伪随机序列统计性能好。     

气候模式中云的垂直重叠假定对模拟的地-气辐射的影响研究

本文将一种新的可以模拟云的多种垂直重叠假定的随机次网格云产生器 (SCG) 放入NCAR/CAM3气候模式中, 利用该产生器得到云的四种垂直重叠结构, 即最大重叠 (MO)、 随机重叠 (RO)、 最大-随机重叠 (MRO) 以及近年来发展的一般重叠 (GenO), 并以GenO为参照研究了这四种云的重叠结构对模拟的地-气辐射的影响, 为气候模式中云的次网格结构选择提供一定的依据。结果表明, MRO、 MO和RO总云量分别与GenO总云量 (全球平均0.64左右) 偏差约-0.012、 -0.034和0.026, 其中MRO最接近GenO。不同重叠假定对地面接收到的短波辐射通量 (DSR) 的改变显著, 在热带对流区达到16 W/m2以上, 相当于GenO下该地区相应量的8%～12%, 通过了95%信度检验; 在中高纬度低云量大的地区也达到4～8 W/m2。不同重叠假定对大气顶出射长波辐射 (OLR) 的改变比其对短波辐射通量的改变小得多, 在热带对流区有极大值3～4 W/m2。不同的云重叠结构的大气加热率垂直廓线不同, 从而影响大气热力结构, 其中长波加热率差值 (最大约0.1～0.26 K/d) 比短波加热率差值 (最大约0.01～0.025 K/d) 几乎大一个量级, 因此, 长波加热率的变化是影响大气热力层结的主要因素。云重叠假定影响地面和大气顶云辐射强迫, 并通过柱辐射强迫使得整层气柱的能量收支发生变化, 不同纬度变化趋势也不同, 从而系统性地改变地-气系统能量在各纬度地区的分配, 影响所模拟的气候系统的演变。     

EM38电磁发生仪测定结果的影响因素分析

通过应用EM38电磁电导仪测量法调查了阿瓦提县丰收灌区土壤盐分含量,并将EM38读数与常规土壤含盐量测定方法所获得的结果进行比较,分析了对仪器电磁产生影响的因素。结果表明,用EM38测得的结果与土壤湿度、土壤质地、土壤温度、土壤盐分的高低、仪器距地面高度的不同都有显著的正相关性。并且对仪器所存在的问题及应用前景进行丫探讨。     

Change of parameters of BCC/RCG-WG for daily non-precipitation variables in China: 1951–1978 and 1979–2007

Parameters of weather generator BCC/RCG-WG for daily non-precipitation variables including maximum temperature, minimum temperature and sunshine hours at 669 stations in China are estimated using history daily records from 1951 to 1978 and from 1979 to 2007 respectively. The changes in the parameters for the two periods are revealed to explore the impact of climate change on these parameters. The results show that the parameters of the non-precipitation variables have experienced different changes. While the annual means and the amplitudes of the seasonal cycle show a clear change, the interannual variability, the timings of the seasonal cycles, and the temporal correlations for each variable remain practically unchanged. This indicates that climate changes in China over the last 57 years are mainly reflected in variations in the means and in the strength of the seasonal cycles. The changed parameters have implications for the stationary assumption implied in the parameter estimation and use of the weather generator for climate change studies.     

光隔测试信号发生器的设计与使用

在数字化前兆遥测台网的信号传输链路中,光隔主侧、光隔副侧是一个故障多发点。为维修方便,笔者研制了光隔测试信号发生器,提高了光隔维修质量。     

新型AgI末端燃烧器及其在增雨作业中的应用

文章对我国新型AgI末端燃烧器的研制情况、结构和改造及其使用作了介绍,简述了这种新催化工具的特点,结合2002年12月至2004年9月,新型AgI末端燃烧器在河北、河南、青海、山东和北京飞机人工增雨探测作业试验,介绍了新型AgI末端燃烧器在3种增雨探测作业机型中的使用情况,并就其中遇到的问题进行了讨论,对如何结合探测作业飞机上所加载的GPS导航数据记录系统及其它辅助记录数据进行催化作业情况记录进行了说明。