Analyse der Laserscanner-basierten Spurwechseldetektion im Kontext des hochautomatisierten Fahrens

Mit der Einführung hochautomatisierter Assistenzfunktionen soll Fahrzeugführern in naher Zukunft eine Abwendung von der Fahraufgabe ermöglicht werden. Neben der Steigerung des individuellen Komforts besteht die Erwartung an eine gleichzeitig erhöhte oder zumindest vergleichbare Sicherheitsbilanz im weiterhin öffentlichen Straßenverkehr. Um eine langfristige, systemische Verantwortungsübernahme zur Verkehrsbeobachtung und Reaktion zu realisieren, muss die durchgängige Beherrschbarkeit erwartbarer Situationen ohne Fahrereingriff in der ausgewiesenen Betriebsdomäne sichergestellt werden. Für die Motor- und Bremsenansteuerung des Egofahrzeugs ist dabei die Erfassung und Auswahl relevanter Verkehrsteilnehmer eine entscheidende Herausforderung - insbesondere bei Einschermanövern in die eigene Spur. Sie kann je nach Kritikalität der eintretenden Situation und in Abhängigkeit von der Reaktionsfähigkeit zur Kollision führen. Den technisch-sicherheitsrelevanten Anforderungen zur Realisierung einer fahrerlosen Steuerung stehen den Automobilherstellern dabei u.a. die wirtschaftlichen und normativen Vorgaben gegenüber: Unter Verwendung zahlreicher Steuergeräte und Sensoren, die vorverarbeitete Informationen der erfassten Objekte liefern, muss eine hinreichende Erfüllung der gesetzlichen und marktspezifischen Anforderungen zum Serieneinsatz unter gleichzeitiger Berücksichtigung des Aufwands erfolgen. Ziel der vorliegenden Arbeit ist die Analyse der notwendigen sensorischen Leistungsfähigkeit zur rechtzeitigen Detektion von Spurwechseln anderer Verkehrsteilnehmer in der Betriebsdomäne einer hochautomatisierten Fahrfunktion zur Ermöglichung einer kollisionsvermeidenden Bremsreaktion. Neben der Darstellung der spezifischen Anforderungen dieser Assistenzstufe im Vergleich zu in Serie befindlichen Systemen wird im ersten Schritt die menschliche Leistungsfähigkeit aus zwei Simulatorstudien bestimmt, um eine Vergleichbarkeit der Risikobilanz für die nachfolgenden Modelle zu ermöglichen. Im nächsten Schritt werden aus den analysierten Eigenschaften der Spurwechselcharakteristik, den Normen zur Straßenanlage und den Bewegungen des sensortragenden Egofahrzeugs die Anforderungen an den sensorisch abzudeckenden Merkmalsraum formuliert. Unter Zuhilfenahme einer existierenden, algorithmischen Modellierung mittels Bayesschen Netzen können die sensorischen Daten zur Erkennung des Spurwechselvorgangs probabilistisch überführt werden. Die Parametrierung des Modells wird im Umfang dieser Arbeit unter Einbezug von Realdaten maschinell trainiert und eine Steigerung der Sensitivität ermöglicht. Für die individuellen, fehlerbehafteten sensorischen Eingangsgrößen wird folglich die Eignung im Gesamtkontext der Spurwechselerkennung simulativ untersucht und in Feldversuchen mit übergeordneter Genauigkeit bewertet. Dabei wird abschließend der für den Automobileinsatz bestimmte und einführend vorgestellte Laserscanner Ibeo ScaLa evaluiert. Die Bewertung der ermittelten Genauigkeiten der Objektdetektion sowie der bereitgestellten Fehlerschätzung erfolgen in Bezug zur erwarteten Risikobilanz des hochautomatisierten Fahrens. Als Ergebnis dieser Arbeit kann für die Spurwechseldetektion anderer Verkehrsteilnehmer neben der ermittelten Reaktionsleistung menschlicher Fahrer auch die damit verbundene, weitreichende Anforderungserfüllung für den betrachteten Laserscanner attestiert werden. Die in Extremfällen fehlende Abdeckung im Randbereich des Sichtfeldes lässt sich durch einfache Erweiterungen in der Fahrstrategie der hochautomatisierten Betriebsdomäne beherrschen. Die experimentell ermittelten Gütemaße erlauben eine Detektion der erwartbaren Spurwechsel bis zu einer durch das verbesserte Modell limitierten Dynamikgrenze. Kollisionen können bei kritischen Spurwechseln bis zu dieser Einschränkung vermieden werden

Second trimester inflammatory and metabolic markers in women delivering preterm with and without preeclampsia.

ObjectiveInflammatory and metabolic pathways are implicated in preterm birth and preeclampsia. However, studies rarely compare second trimester inflammatory and metabolic markers between women who deliver preterm with and without preeclampsia.Study designA sample of 129 women (43 with preeclampsia) with preterm delivery was obtained from an existing population-based birth cohort. Banked second trimester serum samples were assayed for 267 inflammatory and metabolic markers. Backwards-stepwise logistic regression models were used to calculate odds ratios.ResultsHigher 5-α-pregnan-3β,20α-diol disulfate, and lower 1-linoleoylglycerophosphoethanolamine and octadecanedioate, predicted increased odds of preeclampsia.ConclusionsAmong women with preterm births, those who developed preeclampsia differed with respect metabolic markers. These findings point to potential etiologic underpinnings for preeclampsia as a precursor to preterm birth

Emil und die Detektive: Early German sound cinema aesthetic

In 1931 Gerhard Lamprecht directed the film version of Erich Kaestner's popular novel Emil und die Detektive. A hugely successful fil

Neutron captue prompt gamma-ray activation analysis at the NIST Cold Neutron Research Facility

An instrument for neutron capture prompt gamma-ray activation analysis (PGAA) has been constructed as part of the Cold Neutron Research Facility at the 20 MW National Institute of Standards and Technology Research Reactor. The neutron fluence rate (thermal equivalent) is 1.5·10 8 n ·cm −2 ·s −1 , with negligible fast neutrons and gamma-rays. With compact geometry and hydrogen-free construction, the sensitivity is sevenfold better than an existing thermal instrument. Hydrogen background is thirtyfold lower.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43114/1/10967_2005_Article_BF02035470.pd

Measuring the psychosocial burden in women with low-grade abnormal cervical cytology in the TOMBOLA trial: psychometric properties of the Process and Outcome Specific Measure (POSM)

Background There is a need for an instrument to measure the psychosocial burden of receiving an abnormal cervical cytology result which can be used regardless of the clinical management women receive. Methods 3331 women completed the POSM as part of baseline psychosocial assessment in a trial of management of low grade cervical cytological abnormalities. Factor analysis and reliability assessment of the POSM were conducted. Results Two factors were extracted from the POSM: Factor 1, containing items related to worry; and Factor 2 containing items relating to satisfaction with information and support received and change in the way women felt about themselves. Factor 1 had good reliability (Cronbach’s alpha 0.769), however reliability of the Factor 2 was poorer (0.482). Data collected at four subsequent time points demonstrated that the factor structure was stable over time. Conclusion This study demonstrates the presence and reliability of a scale measuring worries within the POSM. This analysis will inform its future use in this population and in other related contexts

SARS-CoV-2 Transmissibility Within Day Care Centers—Study Protocol of a Prospective Analysis of Outbreaks in Germany

Introduction: Until today, the role of children in the transmission dynamics of SARS-CoV-2 and the development of the COVID-19 pandemic seems to be dynamic and is not finally resolved. The primary aim of this study is to investigate the transmission dynamics of SARS-CoV-2 in child day care centers and connected households as well as transmission-related indicators and clinical symptoms among children and adults. Methods and Analysis: COALA (“Corona outbreak-related examinations in day care centers”) is a day care center- and household-based study with a case-ascertained study design. Based on day care centers with at least one reported case of SARS-CoV-2, we include one- to six-year-old children and staff of the affected group in the day care center as well as their respective households. We visit each child's and adult's household. During the home visit we take from each household member a combined mouth and nose swab as well as a saliva sample for analysis of SARS-CoV-2-RNA by real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and a capillary blood sample for a retrospective assessment of an earlier SARS-CoV-2 infection. Furthermore, information on health status, socio-demographics and COVID-19 protective measures are collected via a short telephone interview in the subsequent days. In the following 12 days, household members (or parents for their children) self-collect the same respiratory samples as described above every 3 days and a stool sample for children once. COVID-19 symptoms are documented daily in a symptom diary. Approximately 35 days after testing the index case, every participant who tested positive for SARS-CoV-2 during the study is re-visited at home for another capillary blood sample and a standardized interview. The analysis includes secondary attack rates, by age of primary case, both in the day care center and in households, as well as viral shedding dynamics, including the beginning of shedding relative to symptom onset and viral clearance. Discussion: The results contribute to a better understanding of the epidemiological and virological transmission-related indicators of SARS-CoV-2 among young children, as compared to adults and the interplay between day care and households.Peer Reviewe

River histories : A thematic review

Peer reviewe

Pre-exenterative chemotherapy, a novel therapeutic approach for patients with persistent or recurrent cervical cancer

BACKGROUND: Most cervical cancer patients with pelvic recurrent or persistent disease are not candidates for exenteration, therefore, they only receive palliative chemotherapy. Here we report the results of a novel treatment modality for these patients pre-exenterative chemotherapy- under the rational that the shrinking of the pelvic tumor would allow its resection. METHODS: Patients with recurrent or persistent disease and no evidence of systemic disease, considered not be candidates for pelvic exenteration because of the extent of pelvic tumor, received 3-courses of platinum-based chemotherapy. Response was evaluated by CT scan and bimanual pelvic examination; however the decision to perform exenteration relied on the physical findings. Toxicity to chemotherapy was evaluated with standard criteria. Survival was analyzed with the Kaplan-Meier method. RESULTS: Seventeen patients were studied. The median number of chemotherapy courses was 4. There were 9 patients who responded to chemotherapy, evaluated by bimanual examination and underwent pelvic exenteration. Four of them had pathological complete response. Eight patients did not respond and were not subjected to surgery. One patient died due to exenteration complications. At a median follow-up of 11 months, the median survival for the whole group was 11 months, 3 months in the non-operated and 32 months in those subjected to exenteration. CONCLUSION: Pre-exenterative chemotherapy is an alternative for cervical cancer patients that are no candidates for exenteration because of the extent of the pelvic disease. Its place in the management of recurrent disease needs to be investigated in randomized studies, however, its value for offering long-term survival in some of these patients with no other option than palliative care must be stressed