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The efficiency of vibration control in an automotive semi-active suspension system depends on the quality of information from sensors installed in the vehicle, including information about deflection of the suspension system. The control algorithm for vibration attenuation of the body takes into account its velocity as well as the relative velocity of the suspension. In this paper it is proposed to use the Linear Variable Differential Transformer (LVDT) unit to measure the suspension deflection and then to estimate its relative velocity. This approach is compared with a typical solution implemented in such applications, where the relative velocity is calculated by processing signals acquired from accelerometers placed on the body and on the chassis. The experiments performed for an experimental All-Terrain Vehicle (ATV) confirm that using LVDT units allows for improving ride comfort by better vibration attenuation of the body.

Noise and vibration are common issues that may have a negative impact on human's' health. To minimize their consequences, several vibroacoustical methods may be employed. One well-known method is Piezoelectric Shunt Damping (PSD). Over the years, many approaches have been investigated, from passive, state switching circuits to active pulse-switching. In this paper, the authors propose three PSD implementations-passive Synchronized Switch Damping on Inductor (SSDI), semi-active SSDI and active Synchronized Switch Damping on Voltage source (SSDV)-for a single-panel structure mounted on a rigid-frame casing. The nine Macro Fiber Composite (MFC) elements were mounted on the plate based on preliminary simulations in FreeFEM. Then, the theoretical results were validated by an identification experiment. The main research is concentrated on the Sound Pressure Level (SPL) and structural vibrations reduction for selected frequencies. The active method provided the highest reduction of vibration-up to 5.5 dB for maximal possible loudspeaker level without overdrive and up to 7.5 dB for lower excitation levels.

Analysis of the structural vibration, under the sound excitation is an important part of the quality assurance during the design process of devices. One of the most commonly used method is Laser Doppler Vibrometry (LDV). However, under the rapid fluctuations of temperature, structural resonances are shifted into the other frequencies. In such situation LDV method may be inconvenient, due to the scanning time. In this paper the authors proposed Chladni figures to modal analysis of the double-panel structure, excited by the loudspeaker enclosed inside the casing with a rigid frame. Double-panel structure has been proven to be particularly useful for noise and vibration reduction applications. Vision images, obtained during the experiments are converted to binary patterns, using GLCM matrix, and compared with simulations performed in ANSYS.

Noise may have a negative impact on humans health and well being. Noise is a direct result of the vibration of structures. Many industrial workers and people using household appliances may be exposed to these harmful factors. To minimize their negative consequences, different approaches to noise and vibration reduction may be applied, e.g., active, semi-active or passive methods. In this research, a semi-active approach to vibration reduction of a cubic rigid casing enclosing a noise- and vibration-generating device is presented. One of the casing walls consists of double thin steel panels, coupled with the use of electromagnetic dampers-solenoids installed in the space between the panels. Other casing walls are built of single plywood panels. Vibrations of the outer (radiating) panel of the wall are measured by Macro-Fiber Composite patches. Spectral analysis of structure vibration is carried out to identify the benefits of the proposed coupling solution in terms of vibration reduction of the wall. The frequency range, where vibration reduction is observed, depends on the number of activated solenoids and the duty cycle of a Pulse Width Modulation (PWM) signal. Advantages and drawbacks of the proposed method are discussed and future improvements of the examined setup are suggested.

We present processing methods and visualization techniques for accurately characterizing and interpreting kinematical data of flexion-extension motion of the knee joint based on helical axes. We make use of the Lie group of rigid body motions and particularly its Lie algebra for a natural representation of motion sequences. This allows to analyze and compute the finite helical axis (FHA) and instantaneous helical axis (IHA) in a unified way without redundant degrees of freedom or singularities. A polynomial fitting based on Legendre polynomials within the Lie algebra is applied to provide a smooth description of a given discrete knee motion sequence which is essential for obtaining stable instantaneous helical axes for further analysis. Moreover, this allows for an efficient overall similarity comparison across several motion sequences in order to differentiate among several cases. Our approach combines a specifically designed patient-specific three-dimensional visualization basing on the processed helical axes information and incorporating computed tomography (CT) scans for an intuitive interpretation of the axes and their geometrical relation with respect to the knee joint anatomy. In addition, in the context of the study of diseases affecting the musculoskeletal articulation, we propose to integrate the above tools into a multiscale framework for exploring related data sets distributed across multiple spatial scales. We demonstrate the utility of our methods, exemplarily processing a collection of motion sequences acquired from experimental data involving several surgery techniques. Our approach enables an accurate analysis, visualization and comparison of knee joint articulation, contributing to the evaluation and diagnosis in medical applications.

Acute poisonings with ethylene glycol pose real challenge in the clinical toxicology. The main objective of this study is an analysis of clinical features and identification of prognostic factors in poisoning with ethylene glycol of patients hospitalized in the Toxicology Unit in the years 2000-2009. The medical records of the patients were identified and separated. In the years 2000-2009, 102 patients were hospitalized due to ethylene glycol poisoning, what accounted for 0.38% of total admissions to the unit (26.801 hospitalized people). The mean age of patients amounted 48.05 +/- 12.55 years, the history positive for chronic alcohol abuse was present in 63 (61.76%) cases. Mean values of ethylene glycol concentration were as: in serum 173.14 mg/dl, in urine 6576.46 mg/l. Patients condition on admission varied, with 63 (61.76%) cases described as the severe state. The most frequently noted pathologies were consciousness disturbances and tachycardia. 14 patients died within the analysed group and 63 (61.76%) developed single or multiorgan complications in the course of disease. The most commonly encountered complication were: acute renal failure, anaemia, pneumonia and central nervous system damage. Such parameters as: BE and HCO3 measured on admission should be considered as the prognostic factors, determining the course of the disease and the outcomes of treatment. Poor prognosis may be associated with such clinical features on admission, as: respiratory and circulatory disturbances and cerebral sequelae. The importance of acute poisoning of ethylene glycol is determined both by high frequency of immediate life threatening conditions and by the risk of complications leading to permanent organs damage.

This article presents a method of assessing the economic outcome of implementing an occupational safety and health management system (OSH MS). Developed at the Central Institute for Labour Protection - National Research Institute (Poland), this method focuses on identifying the economic expenses comprising bookkeeping and alternative cost incurred to implement and improve an OSH MS. The method was next used in a study in 20 enterprises. While varying greatly among those enterprises, the alternative cost of implementing and maintaining an OSH MS was much higher than the bookkeeping cost, which was also much lower than the cost of statutory prevention measures. The implementation of an OSH MS resulted in both tangible and intangible benefits, including reduced premiums for work accident insurance.

The main objective of this study was an analysis of the cohort of patients hospitalized due to intoxication with this agent during the period 2000-2009 and investigate factors, which determined the course of poisoning. During the search process, 288 (1.07%) patients were identified within total number of 26801 patients hospitalized. Within analysed cohort male patients formed majority with 227 males, whereas only 61 females were found within this group. The mean methanol blood concentration was 50.09 mg/dl and ethanol - 292.90 mg/dl. Patients condition on admission varied, the most frequently noted pathologies were consciousseness disturbances and tachycardia, namely the former was recorded in 171 cases (59.4%) whereas the latter in 89 patients (30.90%). 11 patients died within the analysed group and 72 developed single or multiorgan complications in the course of poisoning. The most commonly encountered complication was pneumonia. Features of central nervous system (CNS) damage were found in 20 cases (6.94%). Average concentrations of methanol in the group of the 11 deceased patients were: 158.73 mg/ dl, 20.91 mg/dl for ethanol. The average values of arterial blood gases parameters in this group were pH= 6.98; BE=(-) 22.482; HCO3=9.67 mmol/l. Within the non survivors group such complications as CNS damage, seizures, pneumonia, liver injury and pancreatitis were noted more frequently, with statistical significance. The concentrations of methanol and ethanol in the blood on admission and such ABG parameters as pH, BE, HCO3, pCO2 i pO2 also measured on admission should be considered as the prognostic factors, determining the course of the disease and the outcomes of treatment. Poor prognosis may be associated with such clinical features on admission, as: respiratory and circulatory disturbances and cerebral sequelae.

The most common type of economic incentive used in the field of health and safety is experience rating of insurance premiums. The impact of this incentive on occupational health and safety (OHS) costs in the company was analysed by comparing insurance costs with other OHS costs associated with inadequate working conditions, such as accident costs borne by a company. Accident costs were estimated on the basis of research carried out in 10 companies. Insurance costs and their adjustments according to the health and safety level in a company were calculated according to an experience rating model developed in the Central Institute for Labour Protection.

Between 1991 and 1995 there were 75 cases of ethylene glycol poisoning (GE) hospitalised in the Clinic of Acute Poisoning of Institute of Occupational Medicine in Lódź, which comprised 0.9% of the total number of patients. The most common were cases of accidental antifreeze liquids consumption. On admittance to the clinic the state of 59% of the patients was diagnosed as severe and very severe. The main symptoms were: metabolic acidosis, which developed in 77% cases of poisoning, and its consequences--the central nervous damage and the cardiovascular system distributions. The average pH amounted to 7.06 while the base deficit to 22.42 mmol/l. Among complications the most commonly observed was the acute renal failure (84%) which developed during the first 24 hrs in all the 25 cases ending in deaths. Only in 16 out of 63 cases, in which the acute renal failure occurred, multiple hemodialyses proved necessary. Other complications accompanying the poisoning were as follows: anaemia, pneumonia, the irreversible central nervous system damage, the disseminated intravascular coagulation syndrome, and the hepatic damage. The comparative analysis (base on the chi2 and median test) of the deceased and cured patients has shown a significant difference (p < 0.05), among others, concerning the plasma osmolality, the frequency of the acute renal failure and the central nervous system damage occurrence.

A database on individual cases of acute poisonings has been established at the Clinic of Acute Poisonings, Institute of Occupational Medicine. About 3,000 patients yearly are admitted to the Clinic and the mean period of stay is 3-4 days. On the basis of the RDBMS Professional Oracle a method has been designed to prepare, update and select data about the Clinic's patients. The system has been established with a view of developing research on diagnostics and treatment of acute poisonings. Previously, such a study was highly time and effort consuming. Moreover the retrospective material was often inadequate for a detailed analysis. Now, the computer storage of data, makes their utilization more effective and efficient.