Experimental automobile-pedestrian injuries

Fifteen fresh cadaver impacts were conducted in simulation of pedestrian-automobile accidents. The test sled configuration simulated an automobile bumper and hood in "standard" and "nosedive" situations as well as "hard" and "soft" impact surfaces. Instrumentation and film demonstrated large axial compression forces in the struck leg and considerable angular velocity of the torso in all modes. Dissection revealed primary injury at the impact site at low velocities with added remote injury at high velocities. Fracture of the lateral tibial plateau was most common. Lowering the bumper height offered the greatest protection against injury at moderate impact velocities.     

An operational tool to quality control 2D radar reflectivity data for assimilation in COSMO-DE

An operational tool has been designed to enhance the quality of 2D radar reflectivity data for assimilation in COSMO-DE within the German Weather Service (DWD). This article describes the operational algorithms including their testing, the creation of local and composite quality-index fields and their application to improve data assimilation. In the first step, algorithms have been developed and tested to define and identify some of the most severe errors in radar data: corrupt images, low-reflectivity phenomena, which occur under special meteorological conditions, spokes, rings and clutter remnants/speckles. The algorithms use simple but effective tests based on statistical and textural characteristics of spurious signals. The results are stored in an 8-bit quality-index field created concurrently with the radar data at each radar station. It contains quality flags for each individual range bin plus some header information on the overall quality of the underlying data set. The independent coding of error bits enables a differentiated a posteriori decision on whether a range bin is to be used for a given application. These local quality index fields are then used to create a radar precipitation composite, accompanied by a quality-index composite, covering Germany. This tool has now been applied operationally throughout the German radar network. As a result, the radar data quality in data assimilation could be increased.     

Effect of temporal aggregation on multiple time series in the frequency domain

The effect of temporal aggregation on bivariate spectral measures is investigated. First, the low‐frequency regression coefficient turns out to be invariant under aggregation irrespective of differencing, with the exception of when the aggregation of flow and stock variables is combined. Second, the long‐run squared coherency is invariant with respect to aggregation irrespective of differencing. Third, for frequencies different from zero, limiting results for a growing aggregation level m are obtained equal to those at frequency 0 of the underlying basic series. Hence, all frequency domain information is distorted by aggregation apart from the long‐run one. This also holds true for the phase angle that always approaches zero with growing aggregation level m. The sole exception to these findings is the case of the skip sampling stationary series. Moreover, for finite aggregation level, one may exactly quantify the aggregational effect on each cycle of interest. Numerical examples illustrate our results.     

Amount of subarachnoid blood and vasospasm: current aspects. A transcranial Doppler study

Subsequent to admission after aneurysmal subarachnoid haemorrhage (SAH), 120 patients (74 women and 46 men) underwent microsurgical clipping of a total of 158 cerebral aneurysms within 96 hours after the bleed. Their mean age was 46 (20-91) years. Computed tomography (CT) findings were graded according to the modified Fisher scale and all patients had daily transcranial doppler (TCD) recordings of their basal cerebral arteries. In 19% of SAH was grade I on CT, in 44% grade II and in 37% grade III. The rate of patients who developed severe vasospasm as documented by TCD (mean blood flow velocities exceeding 160 cm/s on 2 or more consecutive days) was 39% for grade I patients, 26% for grade II patients and 34% for patients with SAH grade III on the initial CT. There was no difference in the rate of occurrence of severe vasospasm, when the patients were split into 2 groups according to the time of performance of the initial CT scan-within 24 hours, and 48-80 hours after SAH, respectively. It is concluded that the amount of subarachnoid blood on the initial CT scan should no longer be used as the indicator for occurrence and severity of the multifactorial entity vasospasm.     

Characteristics of Staphylococcus hyicus strains isolated from pig carcasses in two different slaughterhouses

In a previous study, we showed that coagulase positive staphylococci, which are often used as indicators for Staphylococcus aureus, are frequently found on pig carcasses. Further characterization of the strains identified only a minor part as S. aureus. Selected non-S. aureus strains were all identified as Staphylococcus hyicus, However, two studies described in this species strains that produce staphylococcal enterotoxins. The aim of the present study was to further characterize such coagulase positive S. hyicus strains isolated from pig carcasses and to assess the results for their food safety relevance. A total of 189 strains from two abattoirs were characterized. Phenotypically, 98.9% showed non-pigmented colonies, 99.5% no haemolysis and 67.7% were egg yolk-positive. DNase activity was found in all but one isolate. Only five of the 189 strains were resistant to the antimicrobials tested. One strain harboured the mecA gene. Exfoliative toxin genes were detected in 31 (16.4%), S. aureus enterotoxin genes in none of the strains.The PFGE genotyping results show only a limited number of clusters. Cluster I included more than 50% of the strains. The fact that similar or closely related PFGE patterns of S. hyicus can be found on carcasses after bleeding in both abattoirs indicates the occurrence of widespread strains in the Swiss pig population. Moreover, the genotyping results revealed a remarkable homogeneity in S. hyicus strains isolated from different process stages in abattoir B, which could indicate a recontamination problem with persisting strains.     

Sparsity-driven reconstruction for FDOT with anatomical priors

In this paper we propose a method based on (2, 1)-mixed-norm penalization for incorporating a structural prior in FDOT image reconstruction. The effect of (2, 1)-mixed-norm penalization is twofold: first, a sparsifying effect which isolates few anatomical regions where the fluorescent probe has accumulated, and second, a regularization effect inside the selected anatomical regions. After formulating the reconstruction in a variational framework, we analyze the resulting optimization problem and derive a practical numerical method tailored to (2, 1)-mixed-norm regularization. The proposed method includes as particular cases other sparsity promoting regularization methods such as l(1)-norm penalization and total variation penalization. Results on synthetic and experimental data are presented.     

底部填充工艺的瞬时温度环境管理

微电子组装的大部份工艺开发都要求将元件做到更小,以便在尺寸日益缩小的便携式设备上实现更多功能。阐述了大元件的底部填充,即一侧的尺寸超过15mm,底部填充的胶量介于30～50mg。大尺寸晶元的制造工艺要求比现有生产线更大的产能,这就给底部填充点胶带来更大的挑战。大元件的产能超过3000个/h时,需要点胶机点出非常多的胶水。如此多的胶水在出胶前通过点胶阀,这将会带来加热的问题-某些工艺要求出胶前胶水必须要加热。这会对胶点尺寸有影响,因为随着温度的变化,底部填充的胶水黏度也会随之变化,从而轻微影响点出的胶量。从而将影响晶元相邻的“非沾染区”。稳定的温度是点胶稳定性的保证,并且能帮助胶水流进晶元下方同时也有助胶水分离从而更容易喷射出来。从研究中可以观察到：系统温度环境（点胶机内部）对点胶的胶水质量有影响。