ІДЕНТИФІКАЦІЯ ГАЛЬМІВНОЇ ХАРАКТЕРИСТИКИ ЕЛАСТИЧНОГО КОЛЕСА МОБІЛЬНОЇ МАШИНИ АНАЛІТИЧНИМИ ЗАСОБАМИ

The article focuses on the possibilities and means of acceptable high-quality reproduction of the braking process of a car wheel (and a car in general). It is emphasised that the problem of accurate estimation of the coefficient of adhesionof a pneumatic wheel to the road remains unsolved: the experimental determination of this coefficient, even in artificially created reference road conditions, always leads to significantly ambiguous results. Thus, the braking process tends toobtain the characteristics of randomness, although, in reality, it is not physically random. Therefore, it is difficult to predict the braking distance, the speed of the start of braking, etc. One of the reasons for such ambiguity is the impossibility toimplement a reliable algorithm that enables qualitatively accurate reproduction of the modes of the usually fast-paced wheel brake control process and, accordingly, a fast-paced realisation of the braking effect. To eliminate this problem, it would be necessary to apply computer simulation modelling of the wheel braking process using the so-called braking characteristic, which must be determined analytically. This satisfactorily flexible analytical description of braking characteristics is proposed in the form of an adaptive dependence of the wheel adhesion coefficient on the road slip coefficient and six so-called regression coefficients. Multiple simulations of the braking process of the wheel (of the car in general) would allow us to identify the regression coefficients of the analytical description and to adequately match all the recorded parameters of each observed braking process.The proposed methodology can be useful either for optimising the car's braking properties or for improving the quality of road accident examinations.Ідеться про можливості й засоби прийнятно якісного відтворення процесу гальмування автомобільного колеса (і автомобіля загалом). Наголошується на тому, що досі нерозв’язаною до кінця залишається проблема точногооцінювання коефіцієнта зчеплення пневматичного колеса з дорогою: експериментальне визначення цього коефіцієнта навіть у штучно створених еталонних дорожніх умовах завжди веде до істотно неоднозначнихрезультатів. Тож процес гальмування набуває ознак випадкового, хоча насправді випадковим він фізично не є. Відтак важко прогнозувати гальмівний шлях, швидкість початку гальмування тощо. Однією з причин такої неоднозначності є неможливість реалізації надійного алгоритму якісно точного відтворення режимів зазвичай швидкоплинного процесу керування колісними гальмами та відповідно швидкоплинної реалізації гальмівного ефекту. Аби знівелювати цю проблему, потрібно було б застосовувати комп’ютерне імітаційне моделювання процесу гальмування колеса з використанням так званої гальмівної характеристики, заданої обов’язковоаналітично. Саме такий задовільно гнучкий аналітичний опис гальмівної характеристики запропоновано у формі адаптивної залежності коефіцієнта зчеплення колеса з дорогою від коефіцієнта його проковзування та шістьохтак званих коефіцієнтів регресії. Багатократна імітація процесу гальмування колеса (автомобіля загалом) дала б змогу ідентифікувати коефіцієнти регресії аналітичного опису та адекватно узгодити усі зафіксовані параметрикожного спостережуваного процесу гальмування.Запропонована методологія може стати корисною чи для оптимізації гальмівних властивостей автомобіля, чи для підвищення якості експертизи дорожньо-транспортної пригоди

Book reviews

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44495/1/10745_2005_Article_BF01880261.pd

Extra-academic transdisciplinarity and scientific pluralism : what might they learn from one another?

Peer reviewe

Culture theory: The developing synthesis from biology

We believe that a useful, complete theory of culture is simpler than the dichotomies promoted by the coevolutionary approach suggest. Culture can be regarded as an aspect of the environment into which each human is born and must succeed or fail, developed gradually by the succession of humans who have lived throughout history. We hypothesize that culture results from the inclusive-fitness-maximizing efforts of all humans who have lived. We think the evidence suggests that cultural traits are, in general, vehicles of genic survival, and that the heritability of cultural traits depends on the judgments (conscious and unconscious) of individuals with regard to their effects on the individual's inclusive fitness.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44477/1/10745_2005_Article_BF01531192.pd

Cardiovascular Risk Reduction with Icosapent Ethyl for Hypertriglyceridemia

BACKGROUND Patients with elevated triglyceride levels are at increased risk for ischemic events. Icosapent ethyl, a highly purified eicosapentaenoic acid ethyl ester, lowers triglyceride levels, but data are needed to determine its effects on ischemic events. METHODS We performed a multicenter, randomized, double-blind, placebo-controlled trial involving patients with established cardiovascular disease or with diabetes and other risk factors, who had been receiving statin therapy and who had a fasting triglyceride level of 135 to 499 mg per deciliter (1.52 to 5.63 mmol per liter) and a low-density lipoprotein cholesterol level of 41 to 100 mg per deciliter (1.06 to 2.59 mmol per liter). The patients were randomly assigned to receive 2 g of icosapent ethyl twice daily (total daily dose, 4 g) or placebo. The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina. The key secondary end point was a composite of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. RESULTS A total of 8179 patients were enrolled (70.7% for secondary prevention of cardiovascular events) and were followed for a median of 4.9 years. A primary end-point event occurred in 17.2% of the patients in the icosapent ethyl group, as compared with 22.0% of the patients in the placebo group (hazard ratio, 0.75; 95% confidence interval [CI], 0.68 to 0.83; P<0.001); the corresponding rates of the key secondary end point were 11.2% and 14.8% (hazard ratio, 0.74; 95% CI, 0.65 to 0.83; P<0.001). The rates of additional ischemic end points, as assessed according to a prespecified hierarchical schema, were significantly lower in the icosapent ethyl group than in the placebo group, including the rate of cardiovascular death (4.3% vs. 5.2%; hazard ratio, 0.80; 95% CI, 0.66 to 0.98; P=0.03). A larger percentage of patients in the icosapent ethyl group than in the placebo group were hospitalized for atrial fibrillation or flutter (3.1% vs. 2.1%, P=0.004). Serious bleeding events occurred in 2.7% of the patients in the icosapent ethyl group and in 2.1% in the placebo group (P=0.06). CONCLUSIONS Among patients with elevated triglyceride levels despite the use of statins, the risk of ischemic events, including cardiovascular death, was significantly lower among those who received 2 g of icosapent ethyl twice daily than among those who received placebo. (Funded by Amarin Pharma; REDUCE-IT ClinicalTrials.gov number, NCT01492361

The adaptive significance of cultural behavior

In this article, I argue that human social behavior is a product of the coevolution of human biology and culture. While critical of attempts by anthropologists to explain cultural practices as if they were independent of the ability of individual human beings to survive and reproduce, I am also leery of attempts by biologists to explain the consistencies between neo-Darwinian theory and cultural behavior as the result of natural selection for that behavior. Instead, I propose that both biological and cultural attributes of human beings result to a large degree from the selective retention of traits that enhance the inclusive fitnesses of individuals in their environments. Aspects of human biology and culture may be adaptive in the same sense despite differences between the mechanisms of selection and regardless of their relative importance in the evolution of a trait. The old idea that organic and cultural evolution are complementary can thus be used to provide new explanations for why people do what they do .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44491/1/10745_2005_Article_BF01531215.pd

Effects of Once-Weekly Exenatide on Cardiovascular Outcomes in Type 2 Diabetes.

Abstract BACKGROUND: The cardiovascular effects of adding once-weekly treatment with exenatide to usual care in patients with type 2 diabetes are unknown. METHODS: We randomly assigned patients with type 2 diabetes, with or without previous cardiovascular disease, to receive subcutaneous injections of extended-release exenatide at a dose of 2 mg or matching placebo once weekly. The primary composite outcome was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The coprimary hypotheses were that exenatide, administered once weekly, would be noninferior to placebo with respect to safety and superior to placebo with respect to efficacy. RESULTS: In all, 14,752 patients (of whom 10,782 [73.1%] had previous cardiovascular disease) were followed for a median of 3.2 years (interquartile range, 2.2 to 4.4). A primary composite outcome event occurred in 839 of 7356 patients (11.4%; 3.7 events per 100 person-years) in the exenatide group and in 905 of 7396 patients (12.2%; 4.0 events per 100 person-years) in the placebo group (hazard ratio, 0.91; 95% confidence interval [CI], 0.83 to 1.00), with the intention-to-treat analysis indicating that exenatide, administered once weekly, was noninferior to placebo with respect to safety (P<0.001 for noninferiority) but was not superior to placebo with respect to efficacy (P=0.06 for superiority). The rates of death from cardiovascular causes, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke, hospitalization for heart failure, and hospitalization for acute coronary syndrome, and the incidence of acute pancreatitis, pancreatic cancer, medullary thyroid carcinoma, and serious adverse events did not differ significantly between the two groups. CONCLUSIONS: Among patients with type 2 diabetes with or without previous cardiovascular disease, the incidence of major adverse cardiovascular events did not differ significantly between patients who received exenatide and those who received placebo. (Funded by Amylin Pharmaceuticals; EXSCEL ClinicalTrials.gov number, NCT01144338 .)