Incorporating Road Networks into Territory Design

Given a set of basic areas, the territory design problem asks to create a predefined number of territories, each containing at least one basic area, such that an objective function is optimized. Desired properties of territories often include a reasonable balance, compact form, contiguity and small average journey times which are usually encoded in the objective function or formulated as constraints. We address the territory design problem by developing graph theoretic models that also consider the underlying road network. The derived graph models enable us to tackle the territory design problem by modifying graph partitioning algorithms and mixed integer programming formulations so that the objective of the planning problem is taken into account. We test and compare the algorithms on several real world instances

Minor Mergers are not enough: The importance of Major Mergers during Brightest Cluster Galaxy assembly

We investigate the roles of major and minor mergers during Brightest Cluster Galaxy (BCG) assembly using surface brightness profiles, line indices, and fundamental plane relations. Based on our own sample (Kluge et al.) and consistently reanalyzed SDSS data, we find that BCGs and luminous normal Ellipticals (LNEs) have similar central velocity dispersions, central absorption line strengths, and central surface brightnesses. However, BCGs are more luminous due to their much larger radial extent. These properties result in a flattening of the Faber-Jackson and Mg$_{\rm b}$-luminosity relations above 10$^{10.6}$ L$_{\odot,g'}$. We use this effect to estimate an amount of 60-80% of accreted and merged light in BCGs relative to LNEs, which agrees with results from cosmological simulations. We determine the contribution of this excess light (EL) at each radius from the difference between the surface flux profiles of BCGs and LNEs. It is small in the center but increases steeply to 50% at already $\sim$3 kpc radius. The shape of these profiles suggests that BCGs could be formed from LNEs in 3 major merger processes. This is also consistent with the mild increase of the S\'ersic indices from $n\approx4$ to $n\approx6$, as confirmed in merger simulations. We note that minor mergers cannot be the dominant origin of the BCG's EL because they deposit too few stars at intermediate radii $r\lesssim20$ kpc. The shape of the EL profile also explains a detected offset of 0.14 dex of the fundamental planes for BCGs and LNEs relative to each other.Comment: 40 pages, 20 figures, 10 tables. Submitted to ApJ

Advanced methods for query routing in peer-to-peer information retrieval

One of the most challenging problems in peer-to-peer networks is query routing: effectively and efficiently identifying peers that can return high-quality local results for a given query. Existing methods from the areas of distributed information retrieval and metasearch engines do not adequately address the peculiarities of a peer-to-peer network. The main contributions of this thesis are as follows: 1. Methods for query routing that take into account the mutual overlap of different peers\u27; collections, 2. Methods for query routing that take into account the correlations between multiple terms, 3. Comparative evaluation of different query routing methods. Our experiments confirm the superiority of our novel query routing methods over the prior state-of-the-art, in particular in the context of peer-to-peer Web search.Eines der drängendsten Probleme in Peer-to-Peer-Netzwerken ist Query-Routing: das effektive und effiziente Identifizieren solcher Peers, die qualitativ hochwertige lokale Ergebnisse zu einer gegebenen Anfrage liefern können. Die bisher bekannten Verfahren aus dem Bereich der verteilten Informationssuche sowie der Metasuchmaschinen werden den Besonderheiten von Peer-to-Peer-Netzwerken nicht gerecht. Die Hautbeiträge dieser Arbeit teilen sich in folgende Schwerpunkte: 1. Query-Routing unter Berücksichtigung der gegenseitigen überlappung der Kollektionen verschiedener Peers, 2. Query-Routing unter Berücksichtigung der Korrelationen zwischen verschiedenen Termen, 3. Vergleichende Evaluierung verschiedener Methoden zum Query-Routing. Unsere Experimente bestätigen die Überlegenheit der in dieser Arbeit entwickelten Verfahren gegenüber den bisher bekannten Verfahren, insbesondere im Kontext von Peer-to-Peer-Websuche

Steadycam vs. Brushless Gimbal : technology, handling and aesthetics

Der Technologie der Kamera-Gimbal wird von manchem das Potenzial zugesprochen, die Steadycam abzulösen. Andere zweifeln das hartnäckig an und verweisen auf technische Nachteile. In dieser Arbeit sollen die beidenTechnologien einander gegenübergestelltund untersuchet werden,worindie Unterschiede in Technik, Handhabung und Ästhetik liegen

Recent Mathematical Approaches to Service Territory Design

Many companies and institutions operate a field service workforce to provide services at their customers\u27 sites. Examples include the sales force of consumer goods manufacturers, the field service technicians of engineering companies, and the nurses of home-health care providers. To obtain clearly defined areas of responsibility, the geographical region under study is in many cases subdivided into service territories, each of which is served by a single field worker or a team of field workers. The design of service territories is subject to various planning criteria. The most common ones are geographical compactness, contiguity, and balance in terms of workload or income potential, but there can be several additional criteria and requirements depending on the specific application. In this thesis, we deal with the development of mathematical models and methods for service territory design problems. Our focus is on planning requirements that are relevant for practice, but have received little attention in the existing literature on territory design so far. We address the question how these requirements can be incorporated into mathematical models and mathematical programming based solution methods. We first present requirements that restrict the feasible assignments of customers to field workers and provide components for their integration into mathematical models. We further consider the requirement that customers must be served multiple times during a given planning horizon. We introduce the resulting problem, which we call the multi-period service territory design problem (MPSTDP). It has not yet been studied in the literature. The emphasis is put on the scheduling task of the MPSTDP, which deals with the assignment of service visits to the days of the planning horizon. We formally define this task and devise a heuristic solution method. Our heuristic produces high-quality solutions and clearly outperforms the existing software product of our industry partner. Moreover, we present the first specially-tailored exact solution method for this task: a branch-and-price algorithm that incorporates specialized acceleration techniques, such as a fast pricing heuristic and symmetry reduction techniques. Ultimately, we study the design of territories for parcel delivery companies. We address the tactical design of the territories and their daily adjustment in order to cope with demand fluctuations. The problem involves determining the number of territories and assigning heterogeneous resources to the territories, a combination not yet addressed in literature. We propose different models as well as a heuristic solution approach, and we perform an extensive case study on real-world problem data

Mutations and amplification of oncogenes in endometrial cancer

Alterations in oncogenes are critical steps in the development of endometrial cancer. To investigate the potential clinical relevance of the amplification of the oncogenes c-erbB2, c-myc, and int-2 and the mutation of K-ras in endometrial cancer, 112 tumors were examined using PCR-based fluorescent DNA technology. Amplification of the three oncogenes and the mutation of K-ras were correlated with age, tumor size, lymph node status, metastases, stage, histological types, grade, steroid hormone receptor expression (estrogen receptor, ER; progesterone receptor, PgR), family history of cancer, previous history of cancer or precursor lesions, and previous history of hormone replacement therapy. Oncogene amplification of c-erbB2 was detected in 18.9%, of c-myc in 2.7% and of int-2 in 4.2%, and K-ras mutation in 11.6%. No significant correlations could be detected between amplification of c-erbB2 and any of the other parameters. Mutation of K-ras is associated with positive expression of PgR. This might indicate that mutation and activation of K-ras are involved in the development of hormonal independence in endometrial cancer

Using Robots in Medical Informatics Education

Although robots have been used for quite some time in education on school and university level, we found no reports of robots being used in the teaching of medical informatics. Thus we present the timetable and structure of a one week, 2 ECTS blocked course for robots in medical informatics initiated in autumn 2022. 19 participants completed the first iteration. We report about the requirements in terms of an appropriate programming environment, the combination among robots and our medical informatics lab and the results of the student’s evaluation of the first instance as well as the experiences with the two types of robots used

Semi-Lorentz invariance, unitarity, and critical exponents of symplectic fermion models

We study a model of N-component complex fermions with a kinetic term that is second order in derivatives. This symplectic fermion model has an Sp(2N) symmetry, which for any N contains an SO(3) subgroup that can be identified with rotational spin of spin-1/2 particles. Since the spin-1/2 representation is not promoted to a representation of the Lorentz group, the model is not fully Lorentz invariant, although it has a relativistic dispersion relation. The hamiltonian is pseudo-hermitian, H^\dagger = C H C, which implies it has a unitary time evolution. Renormalization-group analysis shows the model has a low-energy fixed point that is a fermionic version of the Wilson-Fisher fixed points. The critical exponents are computed to two-loop order. Possible applications to condensed matter physics in 3 space-time dimensions are discussed.Comment: v2: Published version, minor typose correcte

Evaluating Mobile Remote Presence Bots for Medical Consultation in Nursing Homes

Interviews with nursing home residents and medical practitioners who used a telepresence robot aka mobile remote presence bot (MRP) for medical consultation suggest that consulting via MRP is viable option for certain types of consultations. Participants perceived communication via the MRP as generally positive and the interaction felt natural even though it clearly wasn't the same as face-to-face conversation. The interpersonal quality of communication was slightly reduced; consultations may become more effective however this may impact on the emotional relationship between patients and doctors. Medical practitioners would be able to spend more time in conversation with their patients since time spent travelling to residential homes is greatly reduced. Consulting via MRP also offers a safe option during isolation regimes like the ones that have been implemented in long term care facilities around the world during the SARS-CoVID-2 pandemic

Increased performance uncertainty in children with ADHD? - Elevated post-imperative negative variation (PINV) over the ventrolateral prefrontal cortex

Background: We aimed to investigate the influences of attention deficit/hyperactivity disorder (ADHD) on response evaluation, as reflected by the postimperative negative variation (PINV), a slow event-related potential. Methods: We investigated PINV as an indicator of performance uncertainty in an audio-visual contingent negative variation (CNV) paradigm with an interstimulus interval of 3 seconds. A constant, unilateral, quick motor reaction with either the right or the left thumb was required after an auditory forewarned (S1) visual imperative stimulus (S2). We examined 18 ADHD patients (combined or hyperactive-impulsive subtype) aged between 8 and 14 years and an age-, sex and IQ-matched control group of 19 healthy subjects using 64-channel high-density EEG. A first run was recorded drug-free, a second one under methylphenidate (MPH) medication in the ADHD group. Results: We found a significantly increased negativity of the PINV-component over the ventrolateral prefrontal cortex in ADHD children compared to the healthy control group. PINV amplitude was influenced by movement side, most likely due to the slightly more difficult task when left hand responses were required. After the intake of MPH, PINV amplitudes of ADHD children normalized. Conclusions: We conclude that children with ADHD are likely to be more uncertain about the correctness of their performance and interpret the increased PINV as a hint towards compensatory mechanisms for a deficit in the evaluation of contingencies. Further studies are needed to assess the exact extent to which remainders of eye-movement related potentials contribute to PINV amplitude despite the correction for eye-artifacts