南京市通讯辐射环境调查

通过对南京市区进行网格式布点监测，并重点监测典型区域和典型基站，采用基于MapInfo构建的电磁辐射环境评价系统进行现状评价。结果表明，南京市电磁辐射水平总体较低，处于安全水平，部分电磁辐射水平相对较高的区域主要受电视发射塔和广播电台的影响，是南京市电磁辐射环境保护和移动通信基站建设应关注的重点。     

The effect of pup vocalisations on food allocation in a cooperative mammal, the meerkat (Suricata suricatta)

In the meerkat (Suricata suricatta), a cooperative mongoose, pups follow potential feeders while the group is foraging and emit incessant calls when soliciting food from them. In contrast to a ’stationary’ brood of chicks, in which nestlings are fed at a fixed location, meerkat pups are ’mobile’ and become spread out. The question arises whether meerkat pups that experience different constraints to those facing chicks have evolved similar begging strategies. This paper describes the vocalisations that meerkat pups emit in the context of begging and investigates the influence of these calls on food allocation by older group members and on the behaviour of littermates. Meerkat pups use two types of calls when soliciting food from a potential feeder. The most common is a ’repeat’ call, which pups emit continuously when following an older forager over several hours a day. In addition, when a potential feeder finds a prey item, the pups next to it emit a bout of calls with increased calling rate, amplitude and fundamental frequency, termed ’high-pitched’ calls. Observations, together with playback experiments, showed that more prey was allocated to pups that called longer and more intensely. The pup closest to a feeder was almost always fed. The probability of emitting high-pitched calls did not depend on the time since a pup had received food, and the change from repeat to high-pitched calls occurred suddenly. The main function of the high-pitched call, therefore, does not appear to be to signal a pup’s hunger state. More likely, the two calls, in the context of begging, may be an adaptation to energetic constraints in a mobile feeding system. Pups, which are dispersed during foraging, may emit repeat calls over long periods to prevent potential feeders from eating all the prey themselves. At the moment a potential feeder finds prey, pups may give the more intense high-pitched calls to direct feeders to bring the food item to them and not to a littermate. Therefore, unlike the stationary feeding system where chicks emit one type of begging call when the feeder approaches the nest, meerkats, with a mobile feeding system, have evolved two discrete types of vocalisations in the context of begging. Received: 22 November 1999 / Revised: 1 July 2000 / Accepted: 17 July 2000     

A Modeling System to Assess Land Cover Land Use Change Effects on SAV Habitat in the Mobile Bay Estuary

Estuarine ecosystems are largely influenced by watersheds directly connected to them. In the Mobile Bay, Alabama watersheds we examined the effect of land cover and land use (LCLU) changes on discharge rate, water properties, and submerged aquatic vegetation, including freshwater macrophytes and seagrasses, throughout the estuary. LCLU scenarios from 1948, 1992, 2001, and 2030 were used to influence watershed and hydrodynamic models and evaluate the impact of LCLU change on shallow aquatic ecosystems. Overall, our modeling results found that LCLU changes increased freshwater flows into Mobile Bay altering temperature, salinity, and total suspended sediments (TSS). Increased urban land uses coupled with decreased agricultural/pasture lands reduced TSS in the water column. However, increased urbanization or agricultural/pasture land coupled with decreased forest land resulted in higher TSS concentrations. Higher sediment loads were usually strongly correlated with higher TSS levels, except in areas where a large extent of wetlands retained sediment discharged during rainfall events. The modeling results indicated improved water clarity in the shallow aquatic regions of Mississippi Sound and degraded water clarity in the Wolf Bay estuary. This integrated modeling approach will provide new knowledge and tools for coastal resource managers to manage shallow aquatic habitats that provide critical ecosystem services.     

Distribution and transport characteristics of fine particulate matter in beijing with mobile lidar measurements from 2015 to 2018

Accurately quantifying the concentration and transport flux of atmospheric fine particulate matter (PM_2.5) is vital when attempting to thoroughly identify the pollution formation mechanism. In this study, the mobile lidar measurements in Beijing on heavily polluted days in December from 2015 to 2018 are presented. The lidar was mounted on a vehicle, which could perform measurements along designated routes. On the basis of mobile lidar measurements along closed circuits of the 6th Ring Road around Beijing, the spatial distribution and transport flux of PM_2.5 in Beijing were determined with information of wind field. In the spatial distribution, both the concentration and transport of PM_2.5 were revealed to be more significant in the southern section of Beijing. The regional transport layer at heights < 1.3 km plays an important role in pollution formation. The maximum transport flux reached 1600 μg/(m²*sec) on 11 December 2016. With the aerosol boundary layer height determined from the image edge detection (IED) method, the inter-annual variations of the aerosol boundary layer height (ABLH) were also analysed. The ABLH decreased from 0.73 to 0.46 km during the same heavy pollution period from 2015 to 2018. Increasingly adverse aerosol boundary layer (ABL) meteorological factors, including lower ABLH, light winds, temperature inversions, and accumulated moisture, have become necessary for pollution formation in Beijing.     

水体中高锰酸盐指数的流动注射分析方法

研究了用流动注射分析技术测定水体中高锰酸盐指数。使用新发明的耐腐蚀恒流泵、低记忆高效混合器、不存留气泡流通池等部件，通过高温高压，缩短消解时间，从而建立了一种可用于无人值守的自动在线快速监测水体中高锰酸盐指数的分析方法。     

An experimental study on the effect of mobile phone conversation on drivers' reaction time in braking response

Introduction

This paper presents an experimental study in which the effect of three factors (distance between cars, mobile call duration, and time of driving (day or night)) on drivers' reaction time in braking response was investigated.

Methods

The experiment was performed in a real driving environment in which 27 male adults between the ages of 22 and 24 years participated. Three levels of the first two factors (i.e., distance between cars and call duration) and two levels of the last factor (i.e., time of driving) were selected to conduct the experimental study. A full factorial design of experiment with 18 treatment combinations and three replicates of each combination were used. Fifty-four trial runs were performed in a random manner and for each run drivers' reaction time in braking response was measured, which served the data for further analysis. Analysis of variance (ANOVA), interaction effect analysis, and various model adequacy tests were carried out using Design Expert software.

Results

The results of the study indicated that the most important factor affecting the drivers' reaction time in car braking response was the mobile call duration followed by the time of driving, with a high level of interaction between the two factors. It was also found that the distance between cars did not seem to have a significant effect on the reaction time in braking response. It is to be noted that these response times are expected to be higher under normal driving conditions where awareness of experimental environment is not present.

Impact on Industry

The findings of this study would help mobile phone industries in improving safety of mobile phone users in driving environment.     

Driving performance while using cell phones: an observational study

INTRODUCTION: Through spontaneous driving observations, this study sought to examine the impact of using a hands-free cell phone while driving on speed and safe gap keeping behaviors. The study also examined the association between the measure of disturbance created by using a cell phone and the driver's awareness of the disturbance. METHOD: Twenty-three male adults were observed while driving for an hour and a half each; drivers were unaware of being observed. During the session, each of the participants received a phone call, initiated by an associate of the observer. The experiment was divided into two periods during which the experimental parameters were monitored: 10 minutes during conversation on a cell phone and 10 minutes of non-conversation on a hands-free cell phone. After the experiment, the driver was questioned concerning the extent to which his/her driving was disturbed by the cell phone conversation. RESULTS: T-test for matched samples revealed that the gaps between the drivers' cars and those in front of them diminished when drivers were engaged in the cell phone conversations. Repeated measures ANOVA revealed that drivers that had short conversations did not change their speed, while drivers who were engaged in long (over 16 minutes) conversations drove faster. No effect of drivers' awareness toward cell phone-related disturbance on actual driving behavior monitored in the present study was found.     

Nature apps: Waiting for the revolution

Apps are small task-orientated programs with the potential to integrate the computational and sensing capacities of smartphones with the power of cloud computing, social networking, and crowdsourcing. They have the potential to transform how humans interact with nature, cause a step change in the quantity and resolution of biodiversity data, democratize access to environmental knowledge, and reinvigorate ways of enjoying nature. To assess the extent to which this potential is being exploited in relation to nature, we conducted an automated search of the Google Play Store using 96 nature-related terms. This returned data on ~36 304 apps, of which ~6301 were nature-themed. We found that few of these fully exploit the full range of capabilities inherent in the technology and/or have successfully captured the public imagination. Such breakthroughs will only be achieved by increasing the frequency and quality of collaboration between environmental scientists, information engineers, computer scientists, and interested publics.     

手机微波防护器的初步研究

为了解决微波对人脑的辐射问题，提出一种新型的手机微波防护器，经实验测得采用了微波防护器人脑侧微波辐射功率密度一律可降至5μW/cm^2以下，完全符合国家的卫生标准。有效地解决了手机微波对人脑的辐射问题。适用于各种手机，以及发射台站、雷达台站等微波防护。     

GSM移动通信基站电磁辐射污染状况研究

介绍了GSM移动通信基站系统,指出,在进行GSM移动通信基站环境影响分析时,要注意采样点位的设置和测量要求.现场监测结果表明,GSM移动通信基站对环境电磁辐射水平有一定的影响,特别是对50 m内建筑物影响显著,但绝大多数基站基本符合国家有关电磁辐射环境影响标准的要求,在设备正常运行情况下,不会对周围环境造成电磁辐射污染.