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1.
OBJECTIVE: Since the shoulders are rarely seriously injured in frontal or oblique collisions, they have been given low priority in the development of frontal impact crash test dummies. The shoulder complex geometry and its kinematics are of vital importance for the overall dummy kinematics. The shoulder complex also influences the risk of the safety belt slipping off the shoulder in oblique forward collisions. The first aim of this study was to develop a new 50th percentile male THOR shoulder design, while the second was to compare the new shoulder, mounted on a THOR NT dummy, with volunteer, THOR NT, and Hybrid III range of motion and stiffness data. The third aim was to test the repeatability of the new shoulder during dynamic testing and to see how the design behaves with respect to belt slippage in a 45 degrees far-side collision. METHODS: The new 50th percentile THOR shoulder design was developed with the aid of a shell model of the seated University of Michigan Transportation Research Institute (UMTRI) 50th percentile male with coordinates for joints and bony landmarks (Schneider et al., 1983). The new shoulder design has human-like bony landmarks for the acromion and coracoid processes. The clavicle curvature and length are also made similar to that of a male human, as is the range of motion in the anterior-posterior, superior-inferior, and medial-lateral directions. The new shoulder design was manufactured and tested under the same conditions that T?rnvall et al. (2005b) used to compare the shoulder range of motion for the volunteers, Hybrid III, and THOR Alpha. The new design was also tested in two dynamic test configurations: the first was a 0 degrees full-frontal test and the second was a 45 degrees far-side test. The dummy tests were conducted with an R-16 seat with a three-point belt, the Delta V was 27.0+/-0.5 km/h and the maximum peak acceleration was approximately 14.6+/-0.5 g for each test. RESULTS: A new shoulder design with geometry close to that of humans was developed to be retrofitted to the THOR NT dummy. The results showed that the range of motion for the new shoulder complex during static loading was larger by at least a factor of three, for the maximum load (200 N/arm), than that of either the Hybrid III or the THOR NT; this means it was more similar to the volunteers' range of motion. It was observed that the THOR NT with the new shoulder did not slide out of the shoulder belt during a far-side collision. The performance of the new shoulder was reasonably repeatable and stable during both the static tests and the sled tests. CONCLUSION: A new shoulder for the THOR NT has been designed and developed, and data from static range of motion tests and sled tests indicate that the new shoulder complex has the potential to function in a more human-like manner on the THOR dummy.  相似文献   
2.
Chemical accidents during process plant shutdowns may have severe consequences. In spite of this, the safety management systems in place in many companies still mainly cover the normal operations and little explicitly addresses the maintenance shutdown and plant start-up phases. A Finnish research project found that the level of safety during shutdowns is more closely related to the skills of key individuals at the plants and less due to the systematic safety management system of the companies. A guidebook on the topic in conjunction with tools to improve the situation were developed during the project in order to help the companies improve their documentation associated with chemical safety during shutdowns.  相似文献   
3.
Burreau S  Zebühr Y  Broman D  Ishaq R 《Chemosphere》2004,55(7):1043-1052
Pike, perch and roach from rural waters of the Baltic Sea were investigated for possible biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). For this we used data on delta15N, weight and sex of the fish. We were able to separate body size effects from trophic position effects on biomagnification. Both these parameters lead to biomagnification of PCBs and PBDEs. All investigated PCBs (tri- to deca-CBs) biomagnify and the biomagnification potential is positively correlated with hydrophobicity up to log Kow 8.18. Tri- to hepta-BDEs also biomagnify but showed a maximum biomagnification for the penta-BDEs (log Kow 6.46-6.97). The biomagnification of hexa- to hepta-PBDEs was negatively correlated with degree of bromination, likely due to large molecular size or high molecular weight (644-959 Da). Octa-, nona- and deca-BDEs did not biomagnify but were found in two (octa-BDE) and three (nona- and deca-BDEs) of the species, respectively. Increased size of pike is correlated with increased lipid weight based PCB and PBDE concentrations in males but not in females and mean PCB and PBDE concentrations in males are generally higher than in females. For the least hydrophobic PCBs, no sex difference is observed, probably as a consequence of faster clearance of these substances over the gills, making the spawning clearance of PCBs and PBDEs of lesser relative importance.  相似文献   
4.
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) are present in the ecosystem of the Baltic Sea. OH-PBDEs are known to be both natural products from marine environments and metabolites of the anthropogenic polybrominated diphenyl ethers (PBDEs), whereas, MeO-PBDEs appear to be solely natural in origin. Polybrominated dibenzo-p-dioxins (PBDDs) are by-products formed in connection with the combustion of brominated flame retardants (BFRs), but are also indicated as natural products in a red alga (Ceramium tenuicorne) and blue mussels living in the Baltic Sea. The aims of the present investigation were to quantify the OH-PBDEs and MeO-PBDEs present in C. tenuicorne; to verify the identities of PBDDs detected previously in this species of red alga and to investigate whether cyanobacteria living in this same region of the Baltic Sea contain OH-PBDEs, MeO-PBDEs and/or PBDDs. The red alga was confirmed to contain tribromodibenzo-p-dioxins (triBDDs), by accurate mass determination and additional PBDD congeners were also detected in this sample. This is the first time that PBDDs have been identified in a red alga. The SigmaOH-PBDEs and SigmaMeO-PBDEs concentrations, present in C. tenuicorne were 150 and 4.6 ng g(-1) dry weight, respectively. In the cyanobacteria 6 OH-PBDEs, 6 MeO-PBDEs and 4 PBDDs were detected by mass spectrometry (electron capture negative ionization (ECNI)). The PBDDs and OH-PBDEs and MeO-PBDEs detected in the red alga and cyanobacteria are most likely of natural origin.  相似文献   
5.
Approximately 80,000 kg polysulfide sealant containing 10,000-18,000 kg polychlorinated biphenyls (PCB) was deposited at a Swedish municipal landfill station during 1965-1973. Investigations during 1994 showed that soil layers underneath the landfill had concentration of PCB not alarmingly high. The concentration of PCB congeners in ground water samples was elevated 4-750 times compared to a reference sample. Based on samples of ground water, leachate water, and flux chambers measuring evaporation of PCB from the landfill surface, the emission of PCB was estimated to be 1 g sigmaPCB/yr. This very low rate was attributed to the high sorptive capacity of the sealant. Compared to a reference site, the evaporation flux was elevated for the most volatile congeners, but factors 20-1400 lower than from another landfill which was contaminated with PCB in paper-pulp fibres.  相似文献   
6.
Environmental fate determining physical properties including their temperature dependence for five nitro musks and for seven polycyclic musks were estimated. The properties evaluated were vapor pressure in a solid and liquid state (PS and PL), solubility in water (S), Henry's law coefficient (H = PL/S) and log octanol-water partition coefficient (log KOW). Gas chromatography for starting values of vapor pressure estimation and HPLC experiments at 5-20 degrees C for comparison of the theoretical versus experimental solubilities in water were performed. The values of temperature (T) dependence coefficients (Ai and Bi) in equations: log (Property)i = Ai - Bi/T were determined. Values of properties were compared with literature-based data, and an example of their use in environmental hazard estimation by fate modeling was given.  相似文献   
7.
Ishaq R  Näf C  Zebühr Y  Broman D  Järnberg U 《Chemosphere》2003,50(9):1131-1150
Methodology for the determination of biologically active polychlorinated biphenyls (PCBs), non-ortho PCBs, polychlorinated naphthalenes (PCNs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polycyclic aromatic hydrocarbons (PAHs) was used to investigate concentrations and patterns of certain chlorinated PAH (Cl-PAH) in source related samples using synthetic reference mixtures. Thus, in addition to the above mentioned compounds, mono-heptachlorosubstituted fluorenes, phenanthrenes/anthracenes and pyrenes/fluoranthenes (Cl-PAHs) were measured in vapour and particulate air samples from urban road tunnels, samples of settling particulate matter (SPM), and in bottom sediment samples from two point source locations (pulp and paper, and Mg-plant/Fe-Mn-smelter/chlor-alkali) and in the Baltic Sea. Concentrations in air samples followed: PAHs>PCBs>PCNs>non-ortho PCBs or Cl-PAHs>PCDD/Fs. SPM samples collected at increasing distance to the urban area of Stockholm showed: PAHs>PCBs>PCNs>PCDD/Fs>non-ortho PCBs or Cl-PAHs. For all compound groups there was a tenfold (Cl-PAHs fivefold) concentration decrease in SPM samples from highest levels in the urban water area to lowest levels at a distance of 26 km from city centre. PCB profiles of SPM showed similarities with combined profiles of Aroclor 1242 and 1254. PCN profiles of SPM showed similarities with combined profiles of Halowax 1099 and 1014. A correlation with concentration of all tested Cl-PAH and their corresponding parent PAH was found only for Cl-fluorene.  相似文献   
8.
The rapid development of wireless technologies leads to increased human exposure to electromagnetic fields from new devices. Most of these technologies communicate in short to medium range. Communication devices, such as mobile phones (GSM, UMTS, LTE) and wireless computer networks (WLAN, HSDPA, WIMAX) usually work at distances up to some 10 km. Other techniques like Bluetooth, RFID, and wireless USB work at distances up to a few meters. RFID systems can use several frequency bands from low frequencies up to microwaves. The other technologies are mainly using microwave frequencies. Most of these technologies have a rather low-output power, typically <1 W average power, except for fixed transmitters like base stations. This means that the exposure from distant sources is low. If the devices are kept close to the body, the local exposure can be in the range of the levels in the ICNIRP recommendation; this is the case, for example, for mobile phones and WLAN transmitters in laptops. For distant sources, there exist several measurement techniques such as spectrum analysers, measurement receivers, and broadband meters. For sources used close to the body, the local SAR levels have to be determined. For this purpose, instruments measuring the local electric field inside body phantoms have been developed. An alternative to measurements is numerical simulations. If one has knowledge of the signal characteristics of the different technologies then it is possible to find a suitable measurement technique to assess the human exposure.  相似文献   
9.
This study compares in situ observed porewater concentration of persistent organic pollutants (POPs) with predictions by common solid-water phase distribution models. Bottom sediments were sampled in The Grenlandsfjords, Norway, and the interstitial porewater was isolated from the solids by centrifugation and filtration. Both phases were analysed for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F), polycyclic aromatic hydrocarbons (PAH), and organic carbon. Based on the sediments' solid phase content of POPs, organic carbon, and soot carbon, we used the organic matter partitioning (OMP), and also the soot and organic matter partitioning (SOMP) model to estimate the porewater concentration. The OMP model gave better agreement to observations than the SOMP model for both PCDD/Fs and PAHs. The observed concentration of the PCDD/Fs in the sediments' porewater was much higher than in the deep water of the fjord. The logarithm of the organic matter-water partitioning coefficent (log K(OC)) in the porewater had positive linear regression on the logarithm of the octanol-water partitioning coefficient (log K(OW)). The slope of the regression model was indistinguishable from 1, except for the PAHs as a group which had a slope less than 1. This contrasts to previous studies undertaken in The Grenlandsfjords water column, where the slopes were higher than 1 for PCDD/Fs, and the K(OC) were much higher than the K(OW). One explanation may be that the influence of POPs adsorption to soots decrease because competitive sorption by other compounds in the sediment are higher than in the water column. This indicates that the sorption isotherms for these POPs need better understanding in order to be applicable in both the water column and the porewater.  相似文献   
10.
OBJECTIVE: Today, a predominant percentage of vehicles involved in car crashes are exposed to oblique or frontal offset collisions. The aim of this study is to evaluate the 50th percentile male Hybrid III, THOR 99, and THOR Alpha dummies by comparing them with the corresponding kinematics of post mortem human subjects (PMHS) in this type of collision. METHODS: The PMHS data include results from oblique frontal collision tests. They include sled tests with near-side and far-side belt geometries at 15 degrees , 30 degrees , and 45 degrees angles. The test subjects were restrained with a three-point lap-shoulder belt and the Delta V was 30 km/h. RESULTS: The results from the Hybrid III and THOR 99 tests showed that, in most of the test, the head trajectories were an average of approximately 0.1 m shorter than those from equivalent PMHS. The Hybrid III and THOR 99 far-side belt geometry tests showed that the belt remained in place longer on the shoulder of the Hybrid III than on the THOR 99 and the THOR Alpha. This was probably due to a stiffer lumbar spine in the Hybrid III and to a large groove in the steel of the superior surface of the Hybrid III shoulder structure. The THOR 99 escaped from the shoulder belt about 40-50 ms earlier than the THOR Alpha. The results from the THOR Alpha tests show that the head trajectory accorded fairly well with the PMHS data, as long as the shoulder belt did not slip off the shoulder. Although the THOR Alpha shoulder escaped the shoulder belt in the 45 degrees far-side belt geometry, the PMHS did not. This may be due to the THOR Alpha shoulder design, with approximately 0.05 m smaller superior and medial shoulder range-of-motion, in combination with a relatively soft lumbar spine. CONCLUSIONS: The THOR Alpha provides head trajectories similar to those of the PMHS under these loading conditions, provided the shoulder belt remains in position on the shoulder. When the shoulder belt slipped off the dummy shoulder, the head kinematics was altered. The shoulder range-of-motion may be a contributing factor to the overall kinematics of an occupant in oblique frontal impact situations where the occupant moves in a trajectory at an angle from that of the longitudinal direction of the car.  相似文献   
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