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Peter Farkaš and Frank Schindler

Abstract

In this manuscript a simple method is presented for constructing run length limited error control codes from linear binary block codes. The run length limited properties are obtained via addition of a carefully chosen fixed binary vector - a modifier to all codewords without introducing any additional redundancy. Modifier selection is based on a specific property, which can be found in some of the linear binary block codes control matrices. Similar known methods are based on properties of generator matrices. However some codes are specified via control matrices, for example low density parity check codes. The method proposed in this letter could be applied to some of them directly. This is illustrated in this manuscript using example in which a run length limited low density parity check code is obtained from Gallager code.

Open access

Jőrg Arend, Doerthe Kuester, Albert Roessner, Hans Lippert and Frank Meyer

Both gastrointestinal stromal tumors (GIST) and liposarcoma originate from mesenchymal tissue. Their coincidence requires a specific expertise in the diagnostic and therapeutic management.

An unusual exemplary case is described representing a 47-year old female patient with a gastric GIST and a monstrous retroperitoneal liposarcoma with infiltration of the left kidney. The gastric tumor lesion was removed with a tangential resection of the gastric wall; the retroperitoneal tumor lesion was resected including the left kidney. Both tumors were resected with no macroscopic tumor residual. The technically difficult surgical intervention did not show any postoperative complication, and the postoperative course was also uneventful. The complete tumor resection is the treatment of choice in mesenchymal tumors (aim: R0). Depending on histologic tumor classification, resection status and tumor sensitivity, a subsequent radiation and/or chemotherapy is necessary, which allowed to achieve a postoperative tumor-free survival of 6 years including a good quality of life.

Open access

Linda Kauškale and Frank Riemenschneider

Abstract

Investment tendencies in a country and particular region in general have a crucial role in the creation of the sustainable environment of the city, spatial planning and land use management. Green construction has great potential for investing and can provide variety of benefits for sustainable longterm development of the country. The aim of the research is to analyse the environmental and economical substantiation of investments in green buildings, with particular focus on the experience of Germany. The researchers used logical, inductive, quantitative and statistical analysis logical methods, analysis of scientific literature as well as comparative analysis. Lack of information is a peculiarity of real estate market, and especially affects the activities in green building construction, that also shows the necessity of developing economic and environmental criteria for substantiation of the decision-making process. Future research directions have been identified as well.

Open access

Oskar V. Conle and Frank H. Hennemann

Abstract

The new species Acrophylla bhaskarai sp. n. from Larat Island, Indonesia, is described from both sexes and the egg. It is the second species of the genus Acrophylla Gray, 1835 known from outside Australia and the first record of the genus from Wallacea. The discovery raises the number of genera of the tribe Phasmatini known to occur within the boundaries of Wallacea to five.

Open access

Benjamin Garlipp, Jens Schwalenberg, Daniela Adolf, Hans Lippert and Frank Meyer

Epidemiology, Surgical Management and Early Postoperative Outcome in a Cohort of Gastric Cancer Patients of a Tertiary Referral Center in Relation to Multi-Center Quality Assurance Studies

The aim of the study was to analyze epidemiologic parameters, treatment-related data and prognostic factors in the management of gastric cancer patients of a university surgical center under conditions of routine clinical care before the onset of the era of multimodal therapies. By analyzing our data in relation with multi-center quality assurance trials [German Gastric Cancer Study - GGCS (1992) and East German Gastric Cancer Study - EGGCS (2004)] we aimed at providing an instrument of internal quality control at our institution as well as a base for comparison with future analyses taking into account the implementation of evolving (multimodal) therapies and their influence on treatment results.

Material and methods. Retrospective analysis of prospectively gathered data of gastric cancer patients treated at a single institution during a defined 10-year time period with multivariate analysis of risk factors for early postoperative outcome.

Results. From 04/01/1993 through 03/31/2003, a total of 328 gastric cancer patients were treated. In comparison with the EGGCS cohort there was a larger proportion of patients with locally advanced and proximally located tumors. 272 patients (82.9%) underwent surgery with curative intent; in 88.4% of these an R0 resection was achieved (EGGCS/GGCS: 82.5%/71.5%). 68.2% of patients underwent preoperative endoluminal ultrasound (EUS) (EGGCS: 27.4%); the proportion of patients undergoing EUS increased over the study period. Diagnostic accuracy of EUS for T stage was 50.6% (EGGCS: 42.6%). 77.2% of operated patients with curative intent underwent gastrectomy (EGGCS/GGCS: 79.8%/71.1%). Anastomotic leaks at the esophagojejunostomy occurred slightly more frequently (8.8%) than in the EGGCS (5.9%) and GGCS (7.2%); however, postoperative morbidity (36.1%) and early postoperative mortality (5.3%) were not increased compared to the multi-center quality assurance study results (EGGCS morbidity, 45%); EGGCS/GGCS mortality, 8%/8.9%). D2 lymphadenectomy was performed in 72.6% of cases (EGGCS: 70.9%). Multivariate analysis revealed splenectomy as an independent risk factor for postoperative morbidity and ASA status 3 or 4 as an independent risk factor for early postoperative mortality. The rate of splenectomies performed during gastric cancer surgery decreased substantially during the study period.

Conclusions. Preoperative diagnostics were able to accurately predict resectability in almost 90% of patients which is substantially more than the corresponding results of both the EGGCS and the GGCS. In the future, more wide-spread use of EUS will play an increasing role as stage-dependent differentiation of therapeutic concepts gains acceptance. However, diagnostic accuracy of EUS needs to be improved. Our early postoperative outcome data demonstrate that the quality standard of gastric cancer care established by the EGGCS is being fulfilled at our institution in spite of distinct characteristics placing our patients at higher surgical risk. Besides being a valuable instrument of internal quality control, our study provides a good base for comparison with ongoing analyses on future developments in gastric cancer therapy.

Open access

Frank van der Velde

Abstract

The ability to learn constructions may be important for the development of a self-organizing architecture for artificial general intelligence. Constructions are structural relations between more specific or more abstract conceptual representations. They can be derived from the processes of alignment, collocations and distributed equivalences. An architecture that integrates in situ grounded representations with cognitive productivity is ideally suited to learn constructions. This paper described such an architecture, based on neuronal assembly structures and neuronal ’blackboards’ for grounded compositional representations. The paper outlines how constructions could be learned in such an architecture and how the architecture could eventually develop into an autonomous self-organizing architecture for artificial general intelligence.

Open access

Frank Kellenberg, Joel Schmidt and Christian Werner

Abstract

This article refers to the increasing importance of lifelong learning due to changes in the structure of work and society. Learners, teachers and companies need to understand how successful adult learning can look like, which factors of influence exist, and which models are to be applied. As the current academic discussion shows, the area of self-determined and self-regulated learning is becoming increasingly important. Another relevant success factor in this context is the competency to reflect. This article deals with the question of how the three recognized success factors can be linked with each other and brought into line with adult learning. Based on literature review and the author's experience as an adult educator, this article discusses the importance of self-determination, self-regulation and reflection for the successful learning of adults, and highlights the connections between these three influencing factors. The discussion begins with the elaboration of the peculiarities of adult learning in the context of lifelong learning. The three identified influencing factors - self-determination, self-regulation and reflection - are then examined in more detail. These three factors and their influence on adult learning are presented and explained in a basic model. The associated implications for the application in teaching-learning process provide indications for the successful design of learning processes as well as an outlook for future research questions.

Open access

Frank G. Bosman

Abstract

The ninth century Heliand is a poetic retelling of the New Testament in Old Saxon, written by an anonymous monk for the purpose of confirming the conversion his fellow Saxons to the new faith. This conversion had been forced upon them by the Frankish invaders. The author adepts the story of Jesus Christ to fit within the feudal Saxon society and precursory Nordic mythology. This contribution focuses on the Saxon rendering of the Lord’s Prayer as it is situated in the context of the Sermon on the Mount. Several key differences between the Saxon version and its biblical original are pointed out. These mirror and illustrate the attempt of the anonymous author to inculturate Jesus’ message. Finally, it is shown how, by some subtle phrases in the text of the Heliand, the poet of the Heliand is including his Saxon audience to fit themselves spiritually into the biblical story. Through the Heliand, Jesus seems to speak directly to its readers, thus stimulating a transformation of the reader-or hearer-himself.

Open access

Janusz Bedkowski, Timo Röhling, Frank Hoeller, Dirk Shulz and Frank E. Schneider

Abstract

This work concerns the study of 6DSLAM algorithms with an application of robotic mobile mapping systems. The architecture of the 6DSLAM algorithm is designed for evaluation of different data registration strategies. The algorithm is composed of the iterative registration component, thus ICP (Iterative Closest Point), ICP (point to projection), ICP with semantic discrimination of points, LS3D (Least Square Surface Matching), NDT (Normal Distribution Transform) can be chosen. Loop closing is based on LUM and LS3D. The main research goal was to investigate the semantic discrimination of measured points that improve the accuracy of final map especially in demanding scenarios such as multi-level maps (e.g., climbing stairs). The parallel programming based nearest neighborhood search implementation such as point to point, point to projection, semantic discrimination of points is used. The 6DSLAM framework is based on modified 3DTK and PCL open source libraries and parallel programming techniques using NVIDIA CUDA. The paper shows experiments that are demonstrating advantages of proposed approach in relation to practical applications. The major added value of presented research is the qualitative and quantitative evaluation based on realistic scenarios including ground truth data obtained by geodetic survey. The research novelty looking from mobile robotics is the evaluation of LS3D algorithm well known in geodesy.

Open access

Dorian Gaar, Sally Lowick and Frank Preusser

Abstract

Luminescence properties of two samples taken from sand lenses in proglacial outwash de-posits of a piedmont glacier that reached the Swiss midlands during the Last Glacial Maximum are investigated in detail. Deconvolution of CW-OSL decay curves shows that the fast component dominates the OSL signal of quartz. The chemistry of single feldspar grains, in particular the K content in different grains, is determined using wavelength dispersive spectrometry (electron microprobe), revealing an average 12.9 wt.% K of the grains contributing to the IRSL signal. D e distributions are investigated in order to gain insights into partial bleaching, and agreement is found for quartz OSL and feldspar IR50 and pIRIR225 ages for small aliquots and single grains when applying the Minimum Age Model. These ages are also consistent with independent age control. For one sample, ages determined using the Central Age Model result in highly overestimated ages for both feldspar and quartz.