Common Frame Of Reference Research Articles

What about the City? Towards an Urban Post-Growth Research Agenda

This paper explores the (potential) role(s) of cities for societal shifts away from the prioritization of and dependence on economic growth. This paper is rooted in the growing field of ‘degrowth’ and ‘post-growth’ research that empirically and theoretically challenges the possibility and viability of (further) growth-based economic development. Through a systematic literature review of peer-reviewed journal articles, this paper takes stock of the increasing interest of post-growth scholars in cities and urban spaces. This paper identifies seven ways in which cities feature in the post-growth literature: as arenas, as spaces of encounter, as spaces with specific qualities, as (introversive) agents, as targets, as specific scale, and as interdependent configurations. Building on this collection of perspectives on growth-related research in (differently defined) urban contexts, this paper argues that the emergent field of urban post-growth would profit from a common frame of reference and research agenda around which urban post-growth perspectives can cohere. This paper proposes three key areas of research on post-growth in, by, and of cities while putting questions around the growth dependencies of urban systems front and center.

Cooperative reference frame estimation for multi-agent systems via formation control

In this study, we propose a distributed method for multi-agent systems to estimate a global reference frame by constructing a common reference frame for all agents with only local measurements. Our method is a combination of formation control and similarity evaluation of feature point matching. Here, we design a distributed controller to achieve a prescribed configuration and a distributed estimator to construct a common reference frame, which calculates the similarity between the measured relative positions and the prescribed configuration. Then, we quantify the error range between the common reference frame and the global reference frame and show that the constructed common reference frame is the best. The proposed method requires only the information on the relative positions of neighbor robots through local measurements and does not require inter-robot communication or relative posture observation. Finally, we conducted simulations with 12 agents and an experiment with 8 two-wheeled robots to verify the effectiveness of the proposed method.

GPM Ground Validation at NASA Wallops Precipitation Research Facility

Abstract The Wallops Precipitation Research Facility (WPRF) at NASA Goddard Space Flight Center, Wallops Island, Virginia, has been established as a semipermanent supersite for the Global Precipitation Measurement (GPM) Ground Validation (GV) program. WPRF is home to research-quality precipitation instruments, including NASA’s S-band dual-polarimetric radar (NPOL), and a network of profiling radars, disdrometers, and rain gauges. This study investigates the statistical agreement of the GPM Core Observatory Dual-Frequency Precipitation Radar (DPR), combined DPR–GPM Microwave Imager (GMI) and GMI level II precipitation retrievals compared to WPRF ground observations from a 6-yr collection of satellite overpasses. Multisensor observations are integrated using the System for Integrating Multiplatform Data to Build the Atmospheric Column (SIMBA) software package. SIMBA ensures measurements recorded in a variety of formats are synthesized into a common reference frame for ease in comparison and analysis. Given that instantaneous satellite measurements are observed above ground level, this study investigates the possibility of a time lag between satellite and surface mass-weighted mean diameter (Dm), reflectivity (Z), and precipitation rate (R) observations. Results indicate that time lags vary up to 30 min after overpass time but are not consistent between cases. In addition, GPM Core Observatory Dm retrievals are within level I mission science requirements as compared to WPRF ground observations. Results also indicate GPM algorithms overestimate light rain (<1.0 mm h−1). Two very different stratiform rain vertical profiles show differing results when compared to ground reference data. A key finding of this study indicates multisensor DPR/GMI combined algorithms outperform single-sensor DPR algorithm. Significance Statement Satellites are beneficial for global precipitation surveillance because extensive ground instruments are lacking, especially over oceans. Ground validation studies are required to calibrate and improve precipitation algorithms from satellite sensors. The primary goal of this study is to quantify the differences between satellite raindrop size and rain-rate retrieval with ground-based observations. Rainfall-rate algorithms require assumptions about the mean raindrop size. Results indicate Global Precipitation Measurement (GPM)/satellite-based mean raindrop size is within acceptable error (±0.5 mm) with respect to ground measurements. In addition, GPM satellite measurements overestimate light rain (<1.0 mm h−1), which is important during the winter months and at high latitudes. Illuminating the challenges of GPM satellite-based precipitation estimation can guide algorithm developers to improve retrievals.

Differential astrometry with Gaia

Aims. In this paper, we develop a differential astrometric framework that is appropriate for a scanning space satellite such as Gaia. We apply it to the first of the GAREQ fields – the Gaia Relativistic Experiment on Jupiter’s quadrupole – which is the fruit of dedicated efforts within the Gala project focused on measuring the relativistic deflection of light close to Jupiter’s limb. This provides a preliminary assessment of the following: a) the observability of the relativistic deflection of light close to Jupiter and b) Gaia’s astrometric capabilities under extremely difficult conditions such as those around a bright extended object. Methods. Inputs to our differential astrometric model are the charge-coupled device (CCD) transit times as measured by the intermediate data update (IDU) system, transformed to field angles via astrometric global iterative solution (AGIS) geometric calibrations, and the commanded or nominal spacecraft attitude. Actual attitude rates, including medium and high-frequency effects, were estimated from successive CCD pair observations and used to transfer the field angles onto intermediate tangent planes, finally anchored to a common reference frame by fitting a six-parameter model to a set of suitable reference stars. The best-fit parameters provide the target star’s deflection as a time-varying systematic effect. To illustrate the model, we analyzed Gaia astrometric measurements after their calibration through the latest cyclic early data release EDR3/DR3 processing of the GAREQ event in February 2017. We used observations of the closest bright target star successfully observed several times by Gaia in close proximity to Jupiter and surrounding reference stars brighter than G < 13 mag in transits leading up to the time of closest approach and on subsequent transits. Results. The relativistic deflection signal is detected with a signal-to-noise ratio (S/N) of 50 at closest approach by the target star. This signal is the combined effect due to Jupiter and the Sun, mainly dominated by Jupiter’s monopole, demonstrating Gala’s scientific performance under extreme observational conditions. It is an unprecedented detection for the following reasons: a) it is the closest ever to Jupiter’s limb (~7″) in the optical and b) the highest S/N at any wavelength. Finally, this work sets the stage for investigations into disentangling the relativistic quadrupole deflection due to Jupiter with future Gaia astrometric measurements.

Bell inequality violations with random mutually unbiased bases

We examine the problem of exhibiting Bell nonlocality for a two-qudit entangled pure state using a randomly chosen set of mutually unbiased bases (MUBs). Interestingly, even if we employ only two-setting Bell inequalities, we find a significant chance of obtaining a Bell violation if the two parties are individually allowed to measure a sufficient number of MUBs. In particular, for the case of maximally entangled qutrits and ququarts, our numerical estimates indicate that we can obtain near-guaranteed Bell violation by considering only such Bell inequalities. The case of maximally entangled ququints is similar, albeit the chance of ending up with a successful trial decreases somewhat to approximately $99.84%$. Upon a closer inspection, we find that even all these no-violation instances violate some more-setting Bell inequalities. These results suggest that the experimental tests of Bell nonlocality for these higher-dimensional entangled states remain viable even if the two parties do not share a common reference frame.

Large‐Scale Interseismic Strain Mapping of the NE Tibetan Plateau From Sentinel‐1 Interferometry

AbstractThe launches of the Sentinel‐1 synthetic aperture radar satellites in 2014 and 2016 started a new era of high‐resolution velocity and strain rate mapping for the continents. However, multiple challenges exist in tying independently processed velocity data sets to a common reference frame and producing high‐resolution strain rate fields. We analyze Sentinel‐1 data acquired between 2014 and 2019 over the northeast Tibetan Plateau, and develop new methods to derive east and vertical velocities with ∼100 m resolution and ∼1 mm/yr accuracy across an area of 440,000 km2. By implementing a new method of combining horizontal gradients of filtered east and interpolated north velocities, we derive the first ∼1 km resolution strain rate field for this tectonically active region. The strain rate fields show concentrated shear strain along the Haiyuan and East Kunlun Faults, and local contractional strain on fault junctions, within the Qilianshan thrusts, and around the Longyangxia Reservoir. The Laohushan‐Jingtai creeping section of the Haiyuan Fault is highlighted in our data set by extremely rapid strain rates. Strain across unknown portions of the Haiyuan Fault system, including shear on the eastern extension of the Dabanshan Fault and contraction at the western flank of the Quwushan, highlight unmapped tectonic structures. In addition to the uplift across most of the lowlands, the vertical velocities also contain climatic, hydrological or anthropogenic‐related deformation signals. We demonstrate the enhanced view of large‐scale active tectonic processes provided by high‐resolution velocities and strain rates derived from Sentinel‐1 data and highlight associated wide‐ranging research applications.

DATA FUSION FOR CONSTRUCTION MONITORING: HOW LEICA INFINITY MANAGES IMAGES, GNSS DATA, TERRESTRIAL SCANS AND BIM DATA TO EFFICIENTLY TRACK COMPLEX CONSTRUCTION SITES

Abstract. This work explores the importance of properly handling the big variety and amount of measurements data that nowadays can be more and more easily acquired. In fact, in the last decades a new challenge took hold: the academic and industrial focus, in the most different fields, extended from developing new technologies to acquire data and more accurate ways to process it, to also developing software environments to properly handle and process the big amount and large variety of available data. In surveying, when the size and the complexity of the site requires the acquisition of diverse data and the usage of different kind of devices, working in different coordinate systems and operated by multiple people, data process and interpretation is much more error prone. When surveying a complex construction site, early identification of deviations from the design during the construction phase is crucial and has as well a big impact on the project's economic budget. Building Information Modelling (BIM) is the accepted standard for managing information for an asset, and for the construction phase it provides working from a common visualisation of the as-planned model in a 3D environment. The as-built model is generated from a large variety of acquired data, especially when site complexity requires a high level of data integration. Data are usually acquired using GNSS receivers, Terrestrial Laser Scanners (TLS), Total Stations (TS), Digital Levels, and Aerial and Terrestrial photogrammetric devices. Specifically, over the last decade Unmanned Aerial Vehicles (UAV) have been proving their importance also in construction progress and quality monitoring, thanks to their relative easiness of use and the overview they can provide over the construction site. In this work, the value of merging and processing in a single software environment different data sources to reduce errors and get geodetically relevant data is analysed. Specifically, Leica Infinity, a specialised software able to bring various data sources together for working in a common reference frame, is investigated and its effectiveness and efficiency proved for monitoring a complex construction site. The advantages of an integrated data acquisition and process, and in particular the contribution of UAV data in construction site monitoring, both from an accuracy and completeness standpoint, are also assessed.

Encirclement of Moving Targets Using Noisy Range and Bearing Measurements

This paper presents theoretically justified controllers that use relative range and bearing measurements to steer a team of autonomous vehicles, operating without inertial position information, to circular trajectories around a constant-acceleration, constant-velocity, or stationary target. An extended Kalman filter is used to improve the noisy relative measurements and estimate the velocity of the moving target. These estimated values are used in the control laws to encircle constant-velocity moving targets. Lyapunov techniques are utilized to show that the vehicle will converge to the desired circular formations. Additionally, cooperating vehicles are shown to converge to a circular formation with equal temporal spacing using each vehicle’s estimate of the target’s velocity to define a common reference frame. Numerical simulations validate the efficacy of these control laws.

Differential visual and auditory effects in a crossmodal induced Roelofs illusion.

For vision and audition to accurately inform judgments about an object's location, the brain must reconcile the variable anatomical correspondence of the eyes and ears, and the different frames of reference in which stimuli are initially encoded. To do so, it has been suggested that multisensory cues are eventually represented within a common frame of reference. If this is the case, then they should be similarly susceptible to distortion of this reference frame. Following this reasoning, we asked participants to locate visual and auditory probes in a crossmodal variant of the induced Roelofs effect, a visual illusion in which a large, off-center visual frame biases the observer's perceived straight-ahead. Auditory probes were mislocalized in the same direction and with a similar magnitude as visual probes due to the off-center visual frame. However, an off-center auditory frame did not elicit a significant mislocalization of visual probes, indicating that auditory context does not elicit an induced Roelofs effect. These results suggest that the locations of auditory and visual stimuli are represented within a common frame of reference, but that the brain does not rely on stationary auditory context, as it does visual, to maintain this reference frame. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Angle stability enhancement of off-grid microgrids based on model predictive control

To compensate for the lack of inertia and damping, virtual synchronous generator (VSG) control which mimic the synchronous generator (SG) is applied to converters of distributed generation. The synchronous operation of SG and multi-VSG are more likely not be maintained after a large disturbance due to the difference of frequency regulation for the VSG and SG. The rotor motion equations of SG and VSG combination as well as multi-VSG combination are established based on the VSG common reference frame. On this basis, the angle stability of an off-grid microgrid is analyzed and the impact of the controlled current source model of energy storage system (ESS) on transient stability is investigated. A model predictive control (MPC) method using ESS is proposed to enhance the angle stability of the off-gird microgrid. By establishing the prediction model of angle difference, angular frequency difference, and ESS output power and designing the cost function to minimize angle and angular frequency difference and variations of reference power as control variables, the reference active and reactive power can be optimized and then transmit to ESS. The simulation results validate the effectiveness of the proposed MPC method using ESS to enhance the angle stability of off-grid microgrid after large disturbances in the system.

Range-Doppler domain spatial alignment for networked radars

An important prerequisite for the radar network detection is that the measurements from local radars are transformed to a common reference frame without systematic or registration errors. For the signal level alignment, only partial signals are available for global decision-making due to power and bandwidth limitations. In this paper, a low-communication-rate spatial alignment in range-Doppler domain is proposed for networked radars without the prior spatial information (positions and attitudes) of radars, which is different from the existing methods in the trajectory domain or echo domain for alignment. To reduce the radar-to-fusion-center communication-rate, the method of initial constant false alarm rate detection is used to censor the signals in range-Doppler domain from local radars. Based on the spatial alignment model for the networked radars in geometry, a maximization problem is formulated. The objective function is the cross-correlation between the range-Doppler domain signals from different local radars. The optimization problem is solved by a genetic algorithm. Simulation results show that the rotation matrix and translation vector are estimated, and the detection probability of the proposed algorithm is improved after alignment and fusion compared with state-of-art methods.

On Multi-Agent Cognitive Cooperation: Can virtual agents behave like humans?

Individuals tend to cooperate or collaborate to reach a common goal when the going gets tough creating a common frame of reference that is a common mental representation of the situation. Information exchange among people is fundamental for building a shared strategy through the grounding process that exploits different communication channels like vision, haptic, or voice. Indeed, human perception is typically multi-modal.This work proposes a two-fold study investigating the cognitive collaboration process both among humans and virtual agents of a multi-agent reinforcement learning (MARL) system. The experiment with humans consists of an interactive virtual shared environment that uses multi-modal channels (visual and haptics) as interaction cues. Haptic feedback is fundamental for a good sense of presence and for improving the performance in completing a task. In this manuscript, an experiment, consisting of escaping a virtual maze trying to get the best score possible, is introduced. The experiment is meant to be performed in pairs, and the perceptual information is split among the participants. A custom haptic interface has been used for the interaction with the virtual environment. The machine learning case, instead, proposes two virtual agents implemented using a tabular Q-learning paradigm to control a single avatar in a 2D labyrinth, introducing a new form of MARL setting.As it is known, it is not easy to get familiar with haptics for people that have never used it, and that if not properly transmitted, the cognitive workflow does not produce any improvements. However, the main findings of the proposed work are that haptic-driven multi-modal feedback information is a valuable means of collaboration since it allows to establish a common frame of reference between the two participants. The machine learning experiments show that even independent agents, implemented with properly designed rewards, can learn the intentions of the other participant in the same environment and collaborate to accomplish a common task.

Determining the influence of different linking patterns on the stability of students\u2019 score adjustments produced using Video-based Examiner Score Comparison and Adjustment (VESCA)

BackgroundEnsuring equivalence of examiners’ judgements across different groups of examiners is a priority for large scale performance assessments in clinical education, both to enhance fairness and reassure the public. This study extends insight into an innovation called Video-based Examiner Score Comparison and Adjustment (VESCA) which uses video scoring to link otherwise unlinked groups of examiners. This linkage enables comparison of the influence of different examiner-groups within a common frame of reference and provision of adjusted “fair” scores to students. Whilst this innovation promises substantial benefit to quality assurance of distributed Objective Structured Clinical Exams (OSCEs), questions remain about how the resulting score adjustments might be influenced by the specific parameters used to operationalise VESCA. Research questions, How similar are estimates of students’ score adjustments when the model is run with either: fewer comparison videos per participating examiner?; reduced numbers of participating examiners?MethodsUsing secondary analysis of recent research which used VESCA to compare scoring tendencies of different examiner groups, we made numerous copies of the original data then selectively deleted video scores to reduce the number of 1/ linking videos per examiner (4 versus several permutations of 3,2,or 1 videos) or 2/examiner participation rates (all participating examiners (76%) versus several permutations of 70%, 60% or 50% participation). After analysing all resulting datasets with Many Facet Rasch Modelling (MFRM) we calculated students’ score adjustments for each dataset and compared these with score adjustments in the original data using Spearman’s correlations.ResultsStudents’ score adjustments derived form 3 videos per examiner correlated highly with score adjustments derived from 4 linking videos (median Rho = 0.93,IQR0.90–0.95,p < 0.001), with 2 (median Rho 0.85,IQR0.81–0.87,p < 0.001) and 1 linking videos (median Rho = 0.52(IQR0.46–0.64,p < 0.001) producing progressively smaller correlations. Score adjustments were similar for 76% participating examiners and 70% (median Rho = 0.97,IQR0.95–0.98,p < 0.001), and 60% (median Rho = 0.95,IQR0.94–0.98,p < 0.001) participation, but were lower and more variable for 50% examiner participation (median Rho = 0.78,IQR0.65–0.83, some ns).ConclusionsWhilst VESCA showed some sensitivity to the examined parameters, modest reductions in examiner participation rates or video numbers produced highly similar results. Employing VESCA in distributed or national exams could enhance quality assurance or exam fairness.

Towards a First-Person Perspective Mixed Reality Guidance System for Needle Interventions.

While ultrasound (US) guidance has been used during central venous catheterization to reduce complications, including the puncturing of arteries, the rate of such problems remains non-negligible. To further reduce complication rates, mixed-reality systems have been proposed as part of the user interface for such procedures. We demonstrate the use of a surgical navigation system that renders a calibrated US image, and the needle and its trajectory, in a common frame of reference. We compare the effectiveness of this system, whereby images are rendered on a planar monitor and within a head-mounted display (HMD), to the standard-of-care US-only approach, via a phantom-based user study that recruited 31 expert clinicians and 20 medical students. These users performed needle-insertions into a phantom under the three modes of visualization. The success rates were significantly improved under HMD-guidance as compared to US-guidance, for both expert clinicians (94% vs. 70%) and medical students (70% vs. 25%). Users more consistently positioned their needle closer to the center of the vessel’s lumen under HMD-guidance compared to US-guidance. The performance of the clinicians when interacting with this monitor system was comparable to using US-only guidance, with no significant difference being observed across any metrics. The results suggest that the use of an HMD to align the clinician’s visual and motor fields promotes successful needle guidance, highlighting the importance of continued HMD-guidance research.

Frequency-Domain Stability Criteria for Converter-Based Power Systems

Frequency-domain stability criteria are developed for converter-based power systems with any number of converters. The converters may be grid following or grid forming, and the grid can be an ac or hybrid ac-dc network. The converters and the network are all modeled in a common (stationary) reference frame based on small-signal sequence immittances. Coupling over frequency and ac-dc coupling are considered in the most general form. For each type of systems, a frequency-domain model is developed first by nodal analysis and then reformulated to fit the form of a feedback loop with open-loop stability guaranteed by practical conditions. System stability is then determined by a Nyquist-like criterion without the need to check open-loop right-half-plane poles. Further simplification of the system models is made possible by a) generalized <inline-formula><tex-math notation="LaTeX">$n$</tex-math></inline-formula>-port equivalent circuits that include both types of coupling, b) equivalence of stability at internal and external nodes, and c) relationship between dynamics at the perturbation and the coupling frequency. Reduction of a system model into separate single-input-single-output models is presented for several special systems along with their practical applications. Quantitative and experimental results are presented to verify the developed theories.

The doctrine of hardship in contract law: comparative study

The article analyzes the doctrine of hardship in the contract law of Ukraine, France, Germany, England. The grounds for modify ing or terminating the contract due to a hardship are analyzed. A comparative analysis of the court ’ s powers to modify the contract in connection with a hardship is carried out . In French civil law the doctrine of l’imprévision covers all situations in which a party’s contractual obligations have become harder and more onerous to perform because of an unforeseen event posterior to the conclusion of the contract. The conception of hardship was introduced to Ukrainian Civil Code in 2004 for provide the contractual parties to overcome the negative impact of a change of circumstances that was unforeseeable at the time of the conclusion of the contract and renders performance excessively onerous for one of them . This provision is aimed, on the one hand, to restore the balance of interests in contractual relations and to reduce risks, and on the other hand, to keep the contract, as far as possible, preference given to the adaptation of the contract over its termination. Unfortunately, the case law indicates difficulty in implementing the provision of hardship. In English law doctrine is formed the concept of frustration. The only remedy for frustration in common law is termination of the contract; and termination is permanent – English law does not recognize partial frustration nor temporary frustration. German doctrine of hardship has been conceptualized into three aspects requiring a change of circumstances, the parties would not have concluded the contract if they had been aware of this change, and it would not be equitable for one party to deny the other party any amendment of the contract. German approach has been adopted in many harmonization projects and international instruments of contract law, in particular Principles on European Contract Law, Draft Common Frame of Reference, UNIDROIT Principles of International Commercial Contracts. In French, English and Germany law is established three different approaches to cases of contractual impossibility as an exception to pacta sunt servanda: contractual parties are not discharge unless performance has become impossible; as exception for impossibility to some cases; or as separate exception. The main problem nowadays is the lack of definition of “ significant change of circumstances ” in Ukrainian legislation and case law. Such a rule seems to increase legal uncertainty as the criteria of its implementation are vague and have not yet been firmly and precisely defined by case law. In most cases, the courts do not recognize the change of circumstances referred to by the party as significant. Ukrainian c ivil law doctrine defines “ significant change of circumstances ” as change of circumstances that did not depend on the will of parties and was the result of certain actions from the outside; and contains four features: was unforeseeable at the time of the conclusion of the contract, its duration and inevitability, arise without fault of the parties. The law of many states and international soft law gives courts power to modify or terminate the contract in case of change in circumstances. French Civil Code not contains certain grounds in the event of change in circumstances to modify or terminate the contract. They are the same as in case of contract modification or termination by parties. In contrast, Ukrainian legislator decreases significantly judicial intervention in contractual relations. The power of Ukrainian courts to modify the contract is based on the general principles of contractual freedom, if parties in contractual terms lay down modification the contract in case of change in circumstances that was unforeseeable at the time of the conclusion of the contract renders performance excessively onerous for a party.

Rękojmia za wady sprzedanych praw i dóbr niematerialnych w ujęciu historycznym i prawnoporównawczym

The paper deals with historical and comparative legal analysis of the subject of warranty for physical and legal defects. A brief review of European legal orders shows that they are generally oriented towards things (variously understood as tangible or intangible objects). However, modern trade is characterized by an increasing dematerialization of its components. It justifies the question of how the European legal orders and some model acts solved (in the past) and still solve the problem of seller’s responsibility for the sold rights and intangible objects. First, a historical analysis will be made of two issues – the concept of ‘thing’, as well as the object of property, and the object of the sale contract (and at the same time the regime of seller’s responsibility for defects). In the second part, the analysis from the comparative legal perspective will be made, covering selected legal orders in the field of the contract of sale of rights and liability of the seller for defects of these objects. The research has been based on the following legal systems: Austrian, French, German and Swiss. In addition, the Convention on Contracts for the International Sale of Goods (CISG) and the model law – the Draft Common Frame of Reference (DCFR) were analyzed.

Consensus-based formation control using a novel signed protocol

This paper aims to achieve formation control over a group of agents, modeled as single integrators, that exchange state information over an undirected graph. The information available to each agent is the sign of its relative displacement with respect to its neighbors, along different axis of a common frame of reference. It is shown that using a consensus protocol that uses only these signs, and not the magnitudes, of the relative positions, the agents may achieve desired formations shapes at various points in the Euclidean space. Additionally, the sign of this relative displacement is weighted, in the control law, by an edge weight. It is shown that consensus is achievable even when some of these edge weights are negative. Simulations vindicate the analytical claims in the paper.

Basic cost accounting terminology: An English-German dictionary

Cross-country differences in cost accounting philosophies and increasing internationalization are likely to produce linguistic barriers. Moreover, the increasing use of English as a medium of instruction in higher education programs reveals the challenges associated with different cost accounting philosophies particularly. To establish a common understanding of cost accounting terminology, we have created an English-German cost accounting dictionary. We translate all terms using well-established textbooks and the authors’ expertise. This dictionary provides a tool for students and practitioners to study relevant cost accounting terminology. Thereby, the dictionary contributes to the accounting profession and education by creating a common reference frame for communication. In contrast to previous studies, this dictionary focuses on the cost accounting subfield instead of accounting in general, allowing dictionary users to better discriminate disciplinary concepts. Our main conclusion is that the development of such a dictionary is a challenge and requires much effort. Such a dictionary is always bounded by the understanding and interpretation of its developers. Moreover, the dictionary is a snapshot of current cost accounting concepts and will change as new concepts emerge/

Redukcja utrzymująca skuteczność na tle projektu Księgi Pierwszej Kodeksu cywilnego

The article discusses the concept of the so-called “reducing upholding enforcement” (validity) of juridical acts in the light of the draft of Book One of the new Polish civil code (published in 2008). The draft contained a dedicated legal basis allowing courts to reduce the terms (i.e. contractual rights or obligations) of a contract which is invalid – it is so called “reducing upholding effectiveness”. In the article an analysis has been carried out of the most important theoretical and practical backgrounds. The main concern is about the scope of the judge’s power to reduce or even revise the term of the juridical act (contract) and its limit. The comparative context of reduction has also been presented. Reduction is one of the ways to avoid nullity of the juridical act, especially contract clause and is one form of partial invalidity. The main function of it is to protect parties from the disadvantageous and sometimes unexpected effects of invalidity, especially those effects for a party protected by the sanction of nullity (“weaker party”). Reducing the scope of the void term leads to the legal effects of a juridical act remaining in force to the extent allowed and valid in the realm of private law (for instance to cut out the part infringing mandatory rules). This paper includes also comparative remarks on the admissibility of such a reduction in chosen legal systems ius civile and common law tradition. Amongst ius civile systems the doctrine of reduction is widely accepted in German law (called Geltungserhaltende Reduktion). In the common law tradition, reduction is rather inadmissible as a principle. There is a restrictive approach for partial invalidity within the doctrine of severance in contract law. Even though the severability of the contract is only partly invalid, it is widely recognised that reducing invalid contractual terms is hard to accept because of the blue pencil rule and prohibition of such interventions in contractual matters. The article discusses exceptions which can be found in some countries (especially New Zealand or Québec law on illegal contracts). The fundamental problem arising in the area of reducing upholding effectiveness is connected with the fine line between reducing the scope of a void term as a part of the juridical act and revising the matter hidden behind the invalid part of the juridical act. In other words, with the limitations of the courts’ discretion in rewriting an invalid clause. Effects which are intended by reducing the scope of a void term can be achieved in other legal ways. The main alternative is the concept where the sanction of invalidity is established by the judge – in a structured discretion form - which was proposed in the model rules of The Principles of European Contract Law and Draft Common Frame of Reference. That approach reveals some aspects of a structured discretion useful to propose some amendments for the Polish normative basis of reduction. These are statutory factors which are supposed to be taken into consideration when a court exercises its power to sever, reduce or revise an invalid clause or obligation. One basic factor should prevent the so called innocent party from suffering injustice flowing from making a part of a juridical act null and void. This could be done by refusing partial invalidity and instead reducing or revising the invalid part (especially contract term). A version of a legal ground presented by the draft of Book One of the new Polish civil code to reduce the scope of the juridical act clause should be accepted as a step forward in the promotion of justice and efficiency of private law regulations. Implementation of that legal doctrine is supposed to be more detailed and include some aspects of structured discretion i.e. factors limiting the courts’ power to reduce or revise a void clause.