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The LNG-ADP problem is a tactical planning problem for creating an annual delivery program (ADP) for a liquefied natural gas (LNG) producer. An ADP specifies the departure dates of the LNG carriers as well as the delivery dates at the different customers for a period of 12–18 months. The problem can be formulated as maritime inventory routing problem, as it is an important requirement to plan the deliveries such that inventory levels are kept within minimum and maximum limits at the customers as well as the LNG production facility. Inspired by the case of Yamal LNG, we propose a novel discrete-time formulation for the LNG-ADP problem with transshipment and intermediate storage. Our formulation also allows for waiting at the unloading ports. The problem is solved using a rolling horizon heuristic (RHH) for a case based on the Yamal LNG project. We study the impact of different RHH configurations on run time and solution quality. The results show that using a central period that is shorter than the forecast period provides the best objective function, whereas a central period that is longer than the forecast period improves run time. We also explore the effect of allowing waiting at the unloading ports. Waiting does not necessarily improve the objective function value, despite increasing the solution space. However, we observe a reduction in run time for instances where waiting is allowed.

To address the decarbonization challenge, we consider a tramp ship routing problem with speed optimization where the availability of future cargoes is uncertain. We propose a two-stage stochastic programming model to solve it. The first stage of the model decides on the deterministic cargoes with the known availability, while the second stage decides on the detailed routing and scheduling plans with the available spot cargoes revealed. Since sailing speed heavily influences on the fuel consumption, and hence costs and emissions, we include the ships’ speeds along the different sailing legs as decision variables. The opening of the Northern Sea Route (NSR) provides a shorter alternative in connecting Asia and Europe, which may benefit the shipping industry in reducing $$\mathrm {CO_2}$$ CO 2 emissions. We use our model to evaluate the impact of NSR on $$\mathrm {CO_2}$$ CO 2 emissions in tramp shipping considering speed optimization and possible future carbon tax schemes, such as fixed and progressive carbon taxes. The computational results indicate that using the NSR improves the gross margins and reduces the $$\mathrm {CO_2}$$ CO 2 emissions for tramp operators.

Deutsche Bahn (DB) operates a large fleet of rolling stock (locomotives, wagons, and train sets) that must be combined into trains to perform rolling stock rotations. This train composition is a special characteristic of railway operations that distinguishes rolling stock rotation planning from the vehicle scheduling problems prevalent in other industries. DB models train compositions using hyperarcs. The resulting hypergraph models are addressed using a novel coarse-to-fine method that implements a hierarchical column generation over three levels of detail. This algorithm is the mathematical core of DB’s fleet employment optimization (FEO) system for rolling stock rotation planning. FEO’s impact within DB’s planning departments has been revolutionary. DB has used it to support the company’s procurements of its newest high-speed passenger train fleet and its intermodal cargo locomotive fleet for crossborder operations. FEO is the key to successful tendering in regional transport and to construction site management in daily operations. DB’s planning departments appreciate FEO’s high-quality results, ability to reoptimize (quickly), and ease of use. Both employees and customers benefit from the increased regularity of operations. DB attributes annual savings of 74 million euro, an annual reduction of 34,000 tons of CO2 emissions, and the elimination of 600 coupling operations in crossborder operations to the implementation of FEO.

Der Ausbau digitaler Hochgeschwindigkeitsnetze hat auch die hohe Dynamik des Telekommunikationsrechts weiter beschleunigt: etwa bei den Änderungen zur Mitnutzung vorhandener und alternativer Infrastrukturen durch das DigiNetzG bzw. das 5. TKGÄndG. Doch sorgen auch weitere Entwicklungen derzeit für viel Bewegung im TKG: von Neuregelungen zu Endgeräten über Einflüsse wichtiger europäischer Verordnungen bis hin zu den neuesten Änderungen durch das 6. TKGÄndG. Der Berliner Kommentar TKG behält das Geschehen für Sie konsequent im Blick: Neben einer konkurrenzlos aktuellen Kommentierung des TKG zum Erscheinen des Werks finden Sie auch die Entscheidungspraxis der Bundesnetzagentur und der Gerichte detailliert berücksichtigt.

We study the optimal hedging decisions for a risk-averse salmon producer. The hedging decisions are determined using a multistage stochastic programming model. The objective is to maximize the weighted sum of expected revenues from selling salmon either in the spot market or in futures contracts and Conditional Value-at-Risk (CVaR) of the revenues over the planning horizon. The scenario tree for the multistage stochastic programming model is generated based on a procedure that combines Principal Component Analysis and state space modelling. We present results for 3 different CVaR percentiles and different degrees of risk-aversion. The results indicate that salmon producers should use futures contracts to hedge price risk already at fairly low degrees of risk-aversion. The methods described in this paper will be useful as a decision support tool for determining fish companies' risk management and hedging strategies.

When calculating equivalent-volume ice thickness along a vessel's projected route for the purpose of ice resistance estimation, information on both undeformed ice (level ice) and deformed ice (mainly ridges) is needed. Level ice information can be obtained from egg code-based ice charts in form of World Meteorological Organization (WMO) ice thickness ranges. Ridging parameters are sometimes available in ice charts as a supplement to the egg code, but are often missing, especially for the areas in the Arctic, in which case area- and season-specific values of these parameters are obtained from the databases. In this paper, limitation of the latter approach is presented, showing that when the currently available ridging parameters for the Arctic are used, the expected amount of ice along the route underestimates the one measured by a submarine by 29%. As an alternative approach, a novel method for estimating the equivalent-volume ice thickness without requiring ridging parameters is presented. It proposes substitution of WMO ice thickness ranges, currently accounting only for the level ice, with equivalent-volume ice thickness ranges (EVITRs), accounting both for the level ice and for the deformed ice features. The method is based on correlating the amount of deformed ice to the stage of development of the ambient level ice, by analyzing a series of ice thickness profiles for a certain area and season. Consequently, the method provides a mean for the estimation of the total amount of ice and its components along a route based only on the information available in the egg code. The results of a case study in the Arctic show an increased accuracy of the EVITR-based method compared to the ridging parameters-based method, reducing the average error in estimation of the total amount of ice along the vessel's route from 29% to 2%.

Short Sea Pioneer (SSP) is a novel concept for shortsea shipping. The concept is based on daughter ships acting as feeder vessels that meet with the mother ship at suitable locations at sea to tranship cargo. Such a system requires that the routes of both mother ship and daughter ships are synchronized. We provide a path flow formulation for the problem of determining the optimal set of routes for both ships. Non-dominated routes are generated a priori using a dynamic programming label-setting algorithm and used as input for the model. We use the model and solution approach to solve a real-world case from the Norwegian west coast. The results can be used to determine the optimal routes for mother and daughter ships as well as the optimal size of the daughter ships. This is a post-peer-review, pre-copyedit version of an article published in [Flexible Services and Manufacturing Journal] Locked until 23.6.2019 due to copyright restrictions. The final authenticated version is available online at: https://doi.org/10.1007/s10696-018-9317-y

Part 1: Lean Production; International audience; Lean management remains the most popular approach to operational excellence within industry. The next wave of industrial improvement is widely considered to be driven by the application of digital technologies. Organizations are seeking to understand how the two approaches can be utilized synergistically. This paper aims to sketch the landscape for current theories and managerial challenges facing Lean and digital transformation based on Lean principles with respect to organizational design, supply chain planning, decision systems and supplier relationships. We raise fundamental questions that should be addressed by future research in the field of digital lean manufacturing and lean digital transformations.

Thermal hydraulic experiments at system pressures close to the reference reactor are difficult and costly. The pressure chamber technology described in the present paper was developed to improve the accessibility of the test fluid for an application of advanced instrumentation. The main idea consists in accommodating the actual test rig inside a pressure tank and operate it in pressure equilibrium with a filling gas in the chamber. In this way, the walls of the test equipment do not have to be designed as a pressure-bearing boundary. An important feature is a passive approach to maintain the needed very good pressure equilibrium between the fluid in the test setup and the filling gas of the chamber. It is in particular needed in experiments requiring high mass flows of steam supply. Auxiliary systems for pressurizing and cooling the chamber are described. Furthermore, several useful solutions of particular problems are presented, such as the accommodation of delicate devices, like high-speed cameras and infrared cameras, in the pressure chamber, a blurring-free imaging through large observation windows, the sealing of the latter, auxiliary equipment for an efficient handling of the test equipment and the design of penetrations for multiple electric signals through the pressure boundary. Finally, an overview of the experimental programs conducted by now is given, whereby the emphasis is put on examples of measuring results illustrating the potentials of the pressure chamber technology rather than on the scientific output of the given experimental programs.

The Northern Sea Route (NSR) has received increased international attention during the recent years as an alternative transit corridor for shipping between Europe and East Asia. In 2015, the project “Feasibility and Reliability of Shipping on the Northern Sea Route and Modeling of an Arctic Marine Transportation & Logistics System” was established to perform a comprehensive analysis of the current status and future prospects of NSR transit shipping. The project brought together several partners and numerous participants representing industry, governmental bodies, and research groups from Europe, Asia, and Russia, thus providing a unique and comprehensive overview of the subject. This paper is based on the insights gathered during the project. Firstly, it provides a comprehensive overview of the NSR's current regulations and support services. Secondly, it combines the information on the current status of the route with feedback received from the stakeholders during project discussions for the purpose of establishing several possible future operational models for transit shipping along the NSR. It is concluded that the most probable of the analyzed operational models is a combination of ice-strengthened vessels and independent ice-going cargo vessels. This model requires a decrease in severity of ice conditions to allow for year-round commercial navigation, an increase in bunker prices, further development of maritime infrastructure and icebreaking support, and the development of new maritime insurance models. Additionally, establishing transshipment hubs at each end of the NSR with ice-going cargo vessels sailing between them is also considered to be a viable future option.

Penicillium verrucosum is a fungus that can produce ochratoxin A and citrinin, two structurally related nephrotoxic mycotoxins. P. verrucosum usually occurs on wheat but can occasionally also be found in NaCl rich habitats such as salted cheeses or olives, indicating that this fungus can adapt to different environments. The ratio of ochratoxin A to citrinin produced by P. verrucosum is shifted to one of either mycotoxin at the expense of the other dependent on the environmental conditions. High NaCl concentrations shift secondary metabolite biosynthesis towards ochratoxin A production. P. verrucosum copes with NaCl stress by increased ochratoxin A biosynthesis, ensuring chloride homeostasis. Ochratoxin A carries chlorine in its molecule and can excrete chlorine from the cell. It was further shown that the regulation of ochratoxin A by high NaCl conditions is mediated by the HOG MAP kinase signal transduction pathway. Here it is shown that high oxidative stress conditions, evoked for example by increasing concentrations of Cu2 + cations in the growth medium, shift secondary metabolite biosynthesis of P. verrucosum from ochratoxin A to citrinin. The production of citrinin normalizes the oxidative status of the fungal cell under oxidative stress conditions leading to an adaptation to these environmental conditions and protects against increased oxidative stress caused by increased Cu2 + concentrations. Moreover citrinin also protects against light of short wavelength, which may also increase the oxidative status of the environment. The biosynthesis of citrinin is apparently regulated by a cAMP/PKA signaling pathway, because increasing amounts of external cAMP reduce citrinin biosynthesis in a concentration dependent manner. These conditions lead to the cross-regulation of the ochratoxin A/citrinin secondary metabolite pair and support the adaptation of P. verrucosum to different environments.

In order to investigate the two-phase flow behaviour in a complex reactor-typical geometry and to supply suitable data for computational fluid dynamics (CFD) code validation, a model of the hot leg of a pressurised water reactor was built at Helmholtz-Zentrum Dresden Rossendorf (HZDR). The hot leg model is devoted to optical measurement techniques, therefore, a flat test section design was chosen and equipped with large windows. In order to enable the operation at high pressures, the test section is installed in the pressure chamber of the TOPFLOW ( T ransient tw O P hase FLOW ) test facility of HZDR, which is used to perform the experiments under pressure equilibrium with the inside atmosphere. Counter-current flow limitation (CCFL) experiments were performed, simulating the reflux-condenser cooling mode appearing in small break loss-of-coolant-accident (LOCA) scenarios. The fluids used were air and water at room temperature and pressures of up to 3.0 bar, as well as steam and water at pressures of up to 50 bar and the corresponding saturation temperature of 264 °C. One selected 50 bar experiment is presented in detail: the observed behaviour is analysed and illustrated by typical high-speed camera images of the flow. Furthermore, the flooding characteristics obtained from the different experimental runs are presented in terms of the Wallis parameter and Kutateladze number, which are commonly used in the literature. However, a discrepancy was first observed between the air/water and steam/water series. Further investigations show that the steam was probably wet due to heat losses and liquid entrainment from the heater circuit. Consequently, a correction of the steam measurements was required. The amount of parasitic water was evaluated indirectly over the shift of the zero liquid penetration noticed in the CCFL diagram. Finally, the experimental results confirm that the Wallis similarity is appropriate to scale flooding in the hot leg of a pressurised water reactor over a wide range of pressure and temperature conditions.

We study in this paper the effects of volume flexibility, delivery flexibility and operational decision flexibility in operational supply chain planning under uncertain demand. We use a rolling schedule to plan supply chain operations for a whole year. The planning horizon is 4 weeks with deterministic demand in the first week and predicted for the following 3 weeks. Using a case from the Norwegian meat industry, we compare the annual operating results of using a two-stage stochastic programming model to the deterministic expected value problem in order to discuss the impact of flexibility in the supply chain.

A comprehensive database was obtained for stationary upward air–water flows in a vertical pipe with an inner diameter of 195.3 mm using the wire-mesh sensor technology. During the experiments the sensor was always mounted on the top of the test section while the distance between gas injection and measuring plane was varied to up to 18 different L/D by using gas injection chambers at different vertical positions. The gas was injected via holes in the pipe wall. The pressure was kept at 0.25 MPa (absolute) at the location of the active gas injection while the temperature was constant at 30 °C ± 1 K. This procedure exactly represents the evolution of the flow along the pipe, as it would be observed for an injection at a constant height position and a shifting of the measurement plane. The experiments were done for 48 combinations of air and water superficial velocities varying from 0.04 m/s to 1.6 m/s for water and 0.0025 m/s to 3.2 m/s for air. From the raw data time-averaged data as: radial gas volume fraction profiles, bubble size distributions, radial volume fraction profiles decomposed according to the bubble size and the radial profiles of the gas velocity were calculated. Due to the combination of the new experimental procedure with the high spatial and temporal resolution of the wire-mesh sensor technology the data have new quality especially regarding their consistency in the evolution with increasing L/D. This closes a gap for data suitable for CFD code development and validation for two-phase flows, especially for models on bubble coalescence and break-up.

This paper presents a novel technique to study the two-phase flow field around an asymmetric obstruction in a vertical pipe with a nominal diameter of DN200. Main feature of the experiments is the shifting of a half-moon shaped diaphragm causing the obstruction along the axis of the pipe. In this way, the 3D void field is scanned with a stationary wire-mesh sensor that supplies data with a spatial resolution of 3 mm over the cross-section and a measuring frequency of 2.5 kHz. Besides the measurement of time-averaged void fraction fields and bubble-size distributions, novel data evaluation methods were developed to extract estimated liquid velocity profiles as well as lateral components of bubble velocities from the wire-mesh sensor data. The combination of void fraction fields and velocity profiles offer the opportunity to analyse a two-phase flow in a geometry that owns a series of features characteristic for complex components of power and chemical plant equipment. Such characteristics are sharp edges with flow separation, recirculation areas, jet formation, stagnation points and curved stream-lines. The tests were performed with an air–water flow at nearly ambient conditions and with a saturated steam–water mixture at 6.5 MPa. The superficial velocities of liquid and gas or, respectively, vapour were varied in a wide range. The flow structure upstream and downstream of the obstacle is characterized in detail. Bubble size dependent effects of bubble accumulation and migration are discussed on basis of void-fraction profiles decomposed into bubble-size classes. A pronounced influence of the fluid parameters was found in the behaviour of bubbles at the boundary of the jet coming from the non-obstructed part of the cross-section. In case of an air–water flow, bubbles are restrained from entering the jet, a phenomenon which was not observed in high-pressure steam–water flow. A detailed uncertainty analyse of the velocity assessments finishes the presented paper. A blind pre-test calculation with CFX-10 based on the assumption of a mono-disperse bubbly flow has reproduced the overall void and velocity profiles. The results are used for the assessment of the influence of local accelerations on the liquid velocity measurement.

The evolution of the structure of a gas–liquid flow in a large vertical pipe of 195 mm inner diameter was investigated at the TOPFLOW test facility in Rossendorf. Wire-mesh sensors were used to measure sequences of two-dimensional distributions of local instantaneous gas fraction within the complete pipe cross-section. The sensors own a resolution of 3 mm at a frequency of 2500 Hz. Superficial velocities were varied in a range covering flow regimes from bubbly to churn-turbulent flow. The distance between the gas injection and the sensor position was changed using a so-called variable gas injection system. It consists of six gas injection units, each equipped with three rings of injection orifices in the pipe wall (orifice diameter: 1 and 4 mm), which are fed from ring chambers. The gas flow towards these distributor chambers is individually controlled by valves. Measured bubble-size resolved radial gas fraction profiles reveal differences in the lateral migration of bubbles of different size starting from the injection at the wall. The evolution of bubble-size distributions allows to study bubble coalescence and break-up. The influence of the physical properties of the fluid was studied by comparing cold air–water experiments with steam–water tests at 65 bar.

Neuro Linguistic Programming (NLP) Framework has enjoyed enormous popularity in the field of applied psychology. NLP has been used in business, education, law, medicine and psychotherapy to identify people's patterns and alter their responses to stimuli, so they are better able to regulate their environment and themselves. NLP looks at achieving goals, creating stable relationships, eliminating barriers such as fears and phobias, building self-confidence, and self-esteem, and achieving peak performance. Neuro Linguistic Psychotherapy (NLPt) encompasses NLP as framework and set of interventions in the treatment of individuals with different psychological and/or social problems. We aimed systematically to analyse the available data regarding the effectiveness of Neuro Linguistic Psychotherapy (NLPt).The present work is a meta-analysis of studies, observational or randomized controlled trials, for evaluating the efficacy of Neuro Linguistic Programming in individuals with different psychological and/or social problems. The databases searched to identify studies in English and German language: CENTRAL in the Cochrane Library; PubMed; ISI Web of Knowledge (include results also from Medline and the Web of Science); PsycINFO (including PsycARTICLES); Psyndex; Deutschsprachige Diplomarbeiten der Psychologie (database of theses in Psychology in German language), Social SciSearch; National library of health and two NLP-specific research databases: one from the NLP Community (http://www.nlp.de/cgi-bin/research/nlprdb.cgi?action=res_entries) and one from the NLP Group (http://www.nlpgrup.com/bilimselarastirmalar/bilimsel-arastirmalar-4.html#Zweig154).From a total number of 425 studies, 350 were removed and considered not relevant based on the title and abstract. Included, in the final analysis, are 12 studies with numbers of participants ranging between 12 and 115 subjects. The vast majority of studies were prospective observational. The actual paper represents the first meta-analysis evaluating the effectiveness of NLP therapy for individuals with social/psychological problems. The overall meta-analysis found that the NLP therapy may add an overall standardized mean difference of 0.54 with a confidence interval of CI=[0.20; 0.88].Neuro-Linguistic Psychotherapy as a psychotherapeutic modality grounded in theoretical frameworks, methodologies and interventions scientifically developed, including models developed by NLP, shows results that can hold its ground in comparison with other psychotherapeutic methods.