Bypassing the bandwidth theorem with PT symmetry

The beat time {\tau}_{fpt} associated with the energy transfer between two coupled oscillators is dictated by the bandwidth theorem which sets a lower bound {\tau}_{fpt}\sim 1/{\delta}{\omega}. We show, both experimentally and theoretically, that two coupled active LRC electrical oscillators with parity-time (PT) symmetry, bypass the lower bound imposed by the bandwidth theorem, reducing the beat time to zero while retaining a real valued spectrum and fixed eigenfrequency difference {\delta}{\omega}. Our results foster new design strategies which lead to (stable) pseudo-unitary wave evolution, and may allow for ultrafast computation, telecommunication, and signal processing.Comment: 5 pages, 3 figure

Competitive advantage by customer integration. Empirical investigation by the example of German manufacturers of baggage handling systems.

Achieving strong and unique competitive advantages is a goal in the strategic management of customer relations. Sustainable successful relationships to customers to secure profitable business in the face of growing competition are among the most important challenges for firms. In order to remain competitive in the future, German manufacturers have to force the application of innovative state- of-the-art methods to develop competitive advantages to attract and bind customers and to differentiate themselves from their competitors. This is of special relevance under conditions where their products alone are insufficient for the purpose. Such conditions also exist in industries which are crucial for the infrastructure and the care of a state and are of national interest and strategic relevance. Especially commercial airports have to provide a logistical service for the carriage of passengers and luggage and are of strategic importance. The dissertation at hand deals with the question of achieving competitive advantage through the integration of customers in the value creation from the perspective of the baggage handling system manufacturers. It investigates and answers the central question of this research: Is customer integration (CI) a method that can be applied by German manufacturers of Baggage Handling Systems (BHS) to achieve a competitive advantage? The dissertation discusses selected approaches to the application of strategic management in order to survey and to answer the research question, and mirrors it with success factors of CI in combination with technical and legal aspects. Based on the discussion of the approaches Market-based view, the Resource-based view and the Relational view the theoretical discussion finds out that the Market-based and Resource-based view alone are not sufficient to answer the research question and with regard to the industry conditions the relational aspects become more important. This will be underlined by a qualitative empirical investigation that is an essential part of this dissertation and includes the manufacturer and customer perspective and provides an answer on the research question. The theoretical discussion of the market-based view (MBV) discovered that due to the possibility of copying generic strategies, the inadequate consideration of the environmental impact, together with the inadequate approach in the relationships between the market players in the industry, the MBV is insufficient for the research question comprehensively. The theoretical discussion of the resource-based view (RBV) discovered that the complementary relationships, and the goal-oriented bundling of resources amongst the market players, comprise a weak approach. The combinations of resources and the complementary relationships between the players in the industry are crucial factors for achieving CAs and economical rents, and thus resulted in the inappropriateness of the RBV to answer the research question comprehensively. The theoretical discussion of the relational view (RV) discovered that the approach focusing on inter-firm networks and inter-organizational relationships as operational success factors can be used as a complementary supplement to the RBV. The discussion also revealed that the approach focuses on relation-specific assets, knowledge sharing routines, complementary resources / capabilities and effective governance mechanisms as key sources for achieving inter-organizational CAs. All these factors have been taken into consideration when to answering the research question. By the addition of the concept of CI and its success, and considering the frame conditions of the baggage handling industry, the empirical investigation had a comprehensive basis on which to answer the research question following the evaluation and interpretation of the empirical investigation. The investigation found out that in a baggage handling project the manufacturers use a combination of tangible and intangible factors in order to differentiate themselves from their competitors. Intangible factors have a crucial role compared to the tangibles. The main impact comes from relationship related, inter-organizational, human specific and information / knowledge related intangible factors. Customers have confirmed this result by their assessment of factors that ensures that a manufacturer succeeds in competition for the customer by a combination of intangible and tangible factors. This shows that both manufacturer and customer identified intangible factors as the key factors to achieve CAs. This result confirms the approach chosen for this study on the relational view. The investigation also shows that customers and manufacturers divide a baggage handling project into three main process phases: ex-ante to the decision, point of decision, and ex-post of the decision, in which the ex-ante phase is the most critical for manufacturers for achieving CAs, and influences the following phases. During these phases a certain relationship modality between the manufacturer and the customer develops. During the ex-ante phase the customer is involved as a co-innovator with and informer to the manufacturer concerning product development, and assumes a role as a co-producer and / or “partial employee” (Kurzmann and Reinecke, 2009: 207). During the ex-post decision phase the customer is distinguished; as a co-innovator in the development of the product (adaptation of a solution according to environmental changes) and as a co-producer and / or “partial employee” (Kurzmann and Reinecke, 2009: 207) in the achievement stage. Due to the impact of the combination of factors of manufacturer and customer, and the relationship modality that shows the customer’s degree of integration, the integration partners attain advantages that influence their positioning in their individual core businesses (e.g. customer: process costs of baggage handling services compared to other airports). The investigation discovered that the manufacturer achieves CAs over all phases of the project. This is especially so within the legal restrictions that lead to product (system) homogeneity. The way to use the legal system before the restrictions are applied is for the achievement of CAs, the ex-ante phase to the decision is the most relevant phase for the manufacturer. There he has the chance to combine individual tangible and intangible potential factors with those of the customer to create unique symbiotic idiosyncratic achievement bundles that represent the best solution to the customer´s problem. The driving factors for achieving a CA are, under these conditions, based on relational variables in connection with the relationship modality. If the manufacturer is able to realize the ideal potential factor combination, then his competitors face the risk to be the second source in the project, then not being preferred and selected as a project partner by the customer what result in a competitive disadvantage. During the decision phase the combination of potential factors built into the previous phase unofficially influences the customer’s decision. The investigation discovered that due to product (system) homogeneity and legal restrictions the indirect influence of the previous phase regarding the relationship to the customer is crucial for the success of the manufacturer. The quality of the relational factor combinations and the evaluation of the risk failure influence the customer towards the preferred manufacturer, who gains a CA. The competition then face a disadvantage due to costs related to the previous investments in potential factor combinations with the customer. During the ex-post phase of the decision advantages accrue that influence the execution of the project (e.g. time and cost saving, etc.) as well as the core businesses of the involved parties in future projects (e.g. reference, relationship, processual excellence, cost situation, knowledge, etc.). To summarize, the investigation confirms that a German manufacturer able to build an integrated alliance with the customer under the condition that both “(…) combine, exchange, or invest in idiosyncratic assets, knowledge, and resources/capabilities, and/or they employ effective governance mechanisms that lower transaction costs or permit the realization of rents through the synergistic combination of assets, knowledge, or capabilities” can achieve relational rents and CAs (Dyer and Singh, 1998: 662). The CAs achieved by the manufacturer are based on inter-organizational investments in relation-specific assets, a close relationship with the customer based on intangible variables (e.g. trust, commitment, information, fairness, transparency, etc.), the exchange of substantial and joint- learning based knowledge (e.g. time-, information-, knowledge advantage, etc.), as well as combination of complementary scarce resources and capabilities (Dyer and Singh, 1998: 662) and lower transaction costs (Williamson, 1985). Finally, the investigation shows to that a German manufacturer of baggage handling systems can differentiate itself from competitors and achieve competitive advantages under conditions of product (system) homogeneity if the manufacturer integrates the customer into the achievement creation process from the outset of the project by using a combination of potential factors, which help to build a collaborative relationship with the customer. It can be confirmed that customer integration is a method that can be applied by German manufacturers of baggage handling systems to achieve competitive advantages in the airport-specific baggage handling industry.Administración y Dirección de Empresa

What are the effects of climate change on agriculture in North East Central Europe?

Global and climate changes influence the basic conditions for agriculture and so there is not only a demand for a consequent climate protection but also for an adaptation of agriculture to these global changing conditions. For the whole "Maerkisch-Oderland" district (60x40 km) within the moraine landscape of North-East-Germany mainly used for agriculture water balance, nitrogen and sulphur loads as well as crop yields are calculated for two land use and climate scenarios. The comparison between the Scenario2050 and the Scenario2000 reveals significant changes of the water balance (decrease in percolation water, increase in actual evapotranspiration) as well as the concentration of the examined nitrogen in the percolation water. For the study region the crop yields decrease only slightly if the CO2 fertilizing effect is taken into account. Adaptation measures in reaction to the changing climate conditions for an economically secured and sustainable agriculture are recommended.climate change impact assessment, water balance, nitrogen load, crop yield, moraine landscape, Environmental Economics and Policy, Farm Management,

Integrating data and analysis: On bridging data publishers and computational environments

Prior to analysing data, researchers today need to perform the ‘janitorial’ step of the data life cycle. This step involves cleaning, harmonizing, or integrating data and typically relies on loading data from one or multiple sources into a computational environment and one of its native data structures. Loading data consumes only a small fraction of the estimated 80% of time consumed by the ‘janitorial’ step overall in data analysis. Yet, it is baffling how much effort it can take to load data into a native data structure of a computational environment. What could arguably be as straightforward as providing a DOI to a specialized function that returns the corresponding data (and metadata) represented in a data structure native to the computational environment in reality generally amounts to resolving the DOI using a browser, navigating a landing page to identify data and metadata, download data to a file, and ultimately load the data from the file using one of several specialized functions that read data in one of many file formats. The matter is further complicated by Web APIs that - while easing access and download - generally require prior knowledge for how to retrieve data. Such knowledge needs to be encoded in programming code using the computational environment of choice. Surely the required pieces of technology exist to directly access data given a DOI and negotiate content between data provider and consumer so that the computational environment can automatically load data into a native data structure. Yet we still have some way to go before the subtask of loading data into a computational environment is truly easy. Using PANGAEA as a data publisher and a couple of other data sources, and Jupyter as a computational environment, in this talk we highlight the problem and delineate a solution. Specifically, we will demonstrate how, given a DOI name, PANGAEA data can be automatically loaded into a Python Data Analysis Library (pandas) DataFrame with a mere call of a specialized function. We will also discuss some of the challenges and implications of performing such operation on Linked Data. While the prototype does not do justice to the complexity of generalizing the implementation over heterogeneous data sources and data types, we argue the talk contributes to improving how a minor but necessary subtask of the data life cycle may be executed in computational environments, and thus contribute to seamless integration of data and analysis

Neue Methode zur Quantifizierung bodenhydraulischer Kennfunktionen unter Berücksichtigung von Schrumpfung und Quellung

Das erweiterte Verdunstungsverfahren (EEM) mit dem Messgerät HYPROP ermöglicht die simultane Messung der Wasser-retentionskurve (pF) und der ungesättigten hydraulischen Leitfähigkeitsfunktion (K) im Bereich zwischen Sättigung und nahe dem permanenten Welkepunkt (Schindler et a., 2010a und 2010b). Die klassischen Verfahren, Sandbox, Sand-Kaolinbox und Drucktopf für die Messung der pF Kurve und die Multi-Step-Outflow-Methode für die Messung der K-Funktion können durch das HYPROP Gerät ersetzt werden

Simplified method for quantifying and evaluating the hydraulic properties of potting soils and gardening substrates in horticulture

Blumenerden und Substrate werden für die gärtnerische Nutzung als Mischung aus verschiedenen organischen und mineralischen Komponenten hergestellt. Im Rahmen dieser Studie wurden insgesamt 18 handelsübliche Blumen­erden und Substrate hydraulisch untersucht. Ziele der Studie waren (i) die Prüfung des erweiterten Verdunstungs­verfahrens für die Quantifizierung der hydraulischen Eigenschaften der Erden und (ii) die Diskussion und Bewertung der Ergebnisse hinsichtlich deren hydraulischer Eignung. Die Variablen für die hydraulische Bewertung waren (i) die Wasserkapazität im leicht pflanzenverfügbaren Bereich, die (ii) Luftkapazität und (iii) der kapillare Wasseraufstieg. Als begrenzende Faktoren wurden zusätzlich die Schrumpfung und die Wiederbenetzungszeit quantifiziert. Die hydraulische Bewertung erfolgte getrennt für die Anwendung im Topf und unter freier Dränung. Die Messung der hydraulischen Kennwerte erfolgte mit dem HYPROP System (HYdraulic PROPerty analyser), das methodisch auf dem erweiterten Verdunstungsverfahren (EEM) basiert. Das HYPROP ermöglicht die simultane Messung der Wasserretentionskurve und der hydraulischen Leitfähigkeitsfunktion an 250 cm3 Stechzylinderproben bis nahe dem permanenten Welkepunkt. Die Messzeit beträgt 3 bis 10 Tage. Die parallele Messung von mehreren Proben ist möglich. Zusätzlich kann der Schrumpfungsverlauf gemessen werden. Die Wiederbenetzungseigenschaften wurde mit der „Water Drop Penetration Time Method“ quantifiziert. Letzteres konnte während des Verdunstungsversuches erfolgen, so dass alle erforderlichen hydraulischen Informationen in einem Messdurchlauf bestimmt werden konnten. Der gesättigte Wassergehalt der untersuchten Erden lag zwischen 71,8 und 87,1 Vol.-%. Die Wasserversorgung wurde von den meisten geprüften Erden abgesichert. Kritisch hingegen war die Luftkapazität im Blumentopf, wobei diese bei mehr als 50% der Proben unter dem Grenzwert von 10 Vol.-% lag. Dabei zeigte sich, dass Substrate die keine Zusätze von Ton hatten, dafür jedoch Anteile von Kokosfasern, Perlite, Kompost und geringere Beimengungen von Hochmoortorf enthielten, überwiegend Luftkapazitäten größer als 10 Vol.-% hatten. Bewertungsrelevante Unterschiede zwischen den Erden gab es auch im Schrumpfungsverhalten und bei der Wiederbenetzung. Um die Beurteilung der hydraulischen Eignung von Blumenerden effektiver und vergleichbarer machen zu können, sollte ein Bewertungsrahmen entwickelt werden. Die Beurteilung der Einzelgrößen sollte sich an anerkannten Grenzwerten orientieren und die Eignung in einer Punkteskala abgebildet werden. DOI: 10.5073/JfK.2015.06.02, https://doi.org/10.5073/JfK.2015.06.02Gardening substrates are produced for horticultural use as a mixture of different organic and mineral ingredients. 18 commercial gardening substrates were hydraulically investigated during this study. The aims of the study were (i) to examine the extended evaporation method (EEM) for quantifying the hydraulic properties of gardening media and (ii) to discuss and evaluate the results in terms of their suitability for horticulture. The variables for the hydraulic evaluation were (i) the easily plant available water, (ii) the air capacity, and (iii) the capillary rise. Additionally, the shrinkage and the rewetting time were quantified as limiting factors. The hydraulic evaluation was applied separately for cultivation in containers and in the ground (free drainage). The hydraulic properties were measured with the HYPROP system (HYdraulic PROPerty analyser), which is methodologically based on the extended evaporation method (EEM). HYPROP enables the simultaneous measurement of the water retention curve and the unsaturated hydraulic conductivity function of 250 cm3 substrate samples close to the wilting point. The measurement varies between 3 and 10 days. Multiple soil or substrate samples can be studied simultaneously, and shrinkage can be measured. The rewetting behaviour was quantified using the water drop penetration time method. This measurement was applied during the evaporation experiment. This means that all required information could be determined during the evaporation experiment. The saturated water content of the samples varied between 71.8 and 87.1% by vol. Most of the tested substrates guaranteed a supply of water. However, the air capacity in containers was a critical factor. For more than 50% of the investigated substrates the water capacity was lower than the threshold value of 10% by vol. It was found that substrates without clay but containing coir, perlite, compost and a small amount of bog peat generally achieved air capacities greater than 10% by vol. The shrinkage and rewetting time also revealed evaluation-relevant differences between the substrates investigated. A more effective evaluation of the hydraulic suitability of soilless media in horticulture requires the development of an evaluation framework. The assessment of the individual values should be based on accepted threshold values, and the suitability should be evaluated based on a point scale. DOI: 10.5073/JfK.2015.06.02, https://doi.org/10.5073/JfK.2015.06.0

The current state of soil cover in Kazakhstan, problems and solution - Langfassung

This paper presents the research material gained during implementation of the international project led by the International Center for Agricultural Research in Arid Areas (ICARDA) entitled “Sustainable management of land resources in arid regions of Central Asia and Caucasus”. This project focused primarily on irrigation and degraded pastures in south and southeast Kazakhstan. Soils and forage crops were studied using conventional, proven methodological approaches and agro-chemical methods. The subjects of the study were: terrains, soil, water, cultivated and pasture plants (rice, triticale and winter wheat, wormwood-ephemeral, grass-shrub and cereal-grass communities)

Hedgehog signaling patterns the outgrowth of unpaired skeletal appendages in zebrafish

Background: Little is known about the control of the development of vertebrate unpaired appendages such as the caudal fin, one of the key morphological specializations of fishes. Recent analysis of lamprey and dogshark median fins suggests the co-option of some molecular mechanisms between paired and median in Chondrichthyes. However, the extent to which the molecular mechanisms patterning paired and median fins are shared remains unknown.Results: Here we provide molecular description of the initial ontogeny of the median fins in zebrafish and present several independent lines of evidence that Sonic hedgehog signaling emanating from the embryonic midline is essential for establishment and outgrowth of the caudal fin primordium. However, gene expression analysis shows that the primordium of the adult caudal fin does not harbor a Sonic hedgehog-expressing domain equivalent to the Shh secreting zone of polarizing activity ( ZPA) of paired appendages.Conclusion: Our results suggest that Hedgehog proteins can regulate skeletal appendage outgrowth independent of a ZPA and demonstrates an unexpected mechanism for mediating Shh signals in a median fin primordium. The median fins evolved before paired fins in early craniates, thus the patterning of the median fins may be an ancestral mechanism that controls the outgrowth of skeletogenic appendages in vertebrates