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The edge region of the recently discovered fast ion-regulated enhancement mode (FIRE mode) (Han and Park et al 2022 Nature 609 269–275), which primarily operates in the unfavorable ion ∇ B drift configuration, is investigated in detail for the first time. An ion temperature pedestal is identified, while the edge electron density profile remains at low-confinement mode (L-mode) level, displaying characteristics of the edge profiles in improved energy confinement mode (I-mode). The weakly coherent mode (WCM) is observed at around 50 kHz in the spectrum of edge electron density fluctuations measured by beam emission spectroscopy. The weakly coherent feature becomes more pronounced as the amplitude of intermediate-frequency fluctuations (approximately 10–30 kHz) decreases, coinciding with a rise in the height of the temperature pedestal. The WCM propagates in the ion diamagnetic drift direction in the laboratory frame, but its propagation direction in the E × B flow frame has yet to be determined. Nonlinear phase coupling between the low-frequency density fluctuation components and the WCMs is identified, indicating the presence of zonal density. This coupling typically occurs as the H-mode transition approaches, and its potential link to a regulatory process is discussed. When the coupling manifests, intermittent bursts are observed concurrently, not just at the radial location where the WCM amplitude peaks, but throughout the edge region. No other coherent oscillations with finite frequency have been detected thus far. [ABSTRACT FROM AUTHOR]

This paper reports the recent observation of a weakly coherent mode (WCM) within a conventional reflectometer on EAST and successfully determines its poloidal wavenumber range. During the transition from the L-mode to I-mode, the line-averaged density remains nearly unchanged while a significant change is observed in the electron cyclotron emission (ECE) signals at the boundary. The difference between the signals for the two channels at the edge increased, coinciding with the appearance of the WCM and a simultaneous rise in the boundary electron temperature. Further investigation unveiled the modulating role of edge temperature ring oscillation (ETRO) (Liu et al 2020 Nucl. Fusion 60 126016) on high-frequency density fluctuations. Statistical results unveil an inverse relationship between the centeral frequency of the WCM and q _95 . Simulation results provide additional insights, demonstrating that the simulated ‘WCM’ in the density fluctuations aligns with experimental data in terms of center frequency. Additionally, the radial distribution of the simulated ‘WCM’ closely corresponds to regions with the strongest electron temperature gradients. Finally, through a cross-correlation analysis of the simulated fluctuations, the following phase relationship for the wavenumber range of ‘WCM’ was observed: $\alpha_{\widetilde{T}_e} \gt \alpha_{\widetilde{n}_i}\sim\alpha_{\widetilde{\phi}} \gt \alpha_{\widetilde{T}_i}$ .

The improved energy confinement mode (I-mode) is a potential candidate for future fusion power plants, as it combines ELM-free operation with good confinement. The unusual edge transport and turbulence in this regime is still not fully understood. This study analyzes the turbulent structure of the weakly coherent mode (WCM) in ASDEX Upgrade. Measurements from Doppler back-scattering and a thermal helium beam diagnostic are used to determine velocities of the background plasma and the WCM over multiple discharges. A phase velocity of the WCM of the order of 2–5 km s ^−1 in the electron diamagnetic drift direction is found, quantitatively close to a drift wave assuming negligible temperature fluctuations. A good agreement with a previously proposed mechanism behind the I-mode regime is observed. This marks the first experimental verification of a specific understanding of the WCM and the I-mode regime.

Understanding the physics of low-confinement (L-), improved-confinement (I-), and high-confinement (H-) modes is critical for fusion reactors. The finding herein reports observations of two types of turbulence coexisting near the L-mode edge, one magnetohydrodynamic (MHD)-like and another micro-tearing mode (MTM)-like, linked to the H-mode and I-mode confinement in the DIII-D tokamak. Ion-scale magnetic and density turbulence is measured using a Faraday-effect radial-interferometer-polarimeter and beam-emission-spectroscopy (BES). Broadband turbulence spectra of up to ∼600 kHz are observed in two discharges where transitions between L-mode, I-mode, and H-mode occurs. Turbulence is found to be inversely correlated with confinement, meaning lower turbulence power at higher confinement. Distinctively, the high-frequency (HF, >∼100 kHz) magnetic turbulence power changes by the most (55%) during transitions primarily involving energy confinement change, whereas the low-frequency (LF,

This article seeks to analyze the conditions in which group-based pride is rationally appropriate. We first distinguish between the shape and size of an emotion. For the appropriate shape of group-based pride, we suggest two criteria: the distinction between group-based pride and group-based hubris , and between we-mode and I-mode sociality. While group-based hubris is inappropriate irrespective of its mode due to the arrogant, contemptuous, and other-derogating character of this emotion, group-based pride in the we-mode is appropriate in terms of shape if it is felt over an achievement to which the group members collectively committed themselves. For the same reason, members of I-mode groups can feel appropriately proud of the achievement of their group if they have collectively contributed to it. Instead, group-based pride by mere private identification with a successful group can be rationally appropriate if it manifests the person's reduced-agency ideal and is also part of a coherent pattern of rationally interconnected emotions focused on the same ideal. Moreover, we suggest that pride in the success of one's family member or a close friend is typically felt over the rise of social status that one group member's success grants to the group. However, social status cannot be valued for its own sake as this undermines the values upon which social status is founded. Instead, direct or indirect causal contribution to the success of one's child, friend, or student can warrant group-based pride, which may be justified on the basis of shared values without causal contribution as well. Finally, regarding the size of group-based pride, members of we-mode groups are warranted to experience and express more intense pride than members of I-mode groups. Moreover, the proper intensity of this emotion depends on the particular other(s) to whom the expression is directed. Finally, criteria of appropriate size don't apply to shared group-based pride as sharing increases the intensity of emotion by default. [ABSTRACT FROM AUTHOR]

This article seeks to analyze the conditions in which group-based pride is rationally appropriate. We first distinguish between the shape and size of an emotion. For the appropriate shape of group-based pride, we suggest two criteria: the distinction between group-based pride and group-based hubris, and between we-mode and I-mode sociality. While group-based hubris is inappropriate irrespective of its mode due to the arrogant, contemptuous, and other-derogating character of this emotion, group-based pride in the we-mode is appropriate in terms of shape if it is felt over an achievement to which the group members collectively committed themselves. For the same reason, members of I-mode groups can feel appropriately proud of the achievement of their group if they have collectively contributed to it. Instead, group-based pride by mere private identification with a successful group can be rationally appropriate if it manifests the person’s reduced-agency ideal and is also part of a coherent pattern of rationally interconnected emotions focused on the same ideal. Moreover, we suggest that pride in the success of one’s family member or a close friend is typically felt over the rise of social status that one group member’s success grants to the group. However, social status cannot be valued for its own sake as this undermines the values upon which social status is founded. Instead, direct or indirect causal contribution to the success of one’s child, friend, or student can warrant group-based pride, which may be justified on the basis of shared values without causal contribution as well. Finally, regarding the size of group-based pride, members of we-mode groups are warranted to experience and express more intense pride than members of I-mode groups. Moreover, the proper intensity of this emotion depends on the particular other(s) to whom the expression is directed. Finally, criteria of appropriate size don’t apply to shared group-based pride as sharing increases the intensity of emotion by default.

In some conditions, I-mode plasmas can feature pedestal relaxation events (PREs) that transiently enhance the energy reaching the divertor target plates. To shed light on their appearance, characteristics and energy reaching the divertor targets, a comparative study between two tokamaks â€" Alcator C-Mod and ASDEX Upgrade â€" is carried out. It is found that PREs appear only in a subset of I-mode discharges, mainly when the plasma is close to the H-mode transition. Also, a growing oscillating precursor before the PRE onset is observed in the region close to the separatrix in both devices, and a discussion on a possible triggering mechanism is outlined. The PRE relative energy loss from the confined region is found to increase with decreasing pedestal top collisionality ν ped * . Similarly, also the relative electron temperature drop at the pedestal top, which is related to the conductive energy loss, rises with decreasing ν ped * . Based on these relations, the PRE relative energy loss in future devices such as DEMO and ARC is estimated. Finally, the divertor peak energy fluence due to the PRE is measured on each device. Those values are then compared to the model introduced in Eich et al (2017 Nucl. Mater. Energy 12 84â€"90) for type-I edge localized modes. The model is shown to provide an upper boundary for PRE energy fluence data, while a lower boundary is found by dividing the model by three. These two boundaries are used to make projections of the PRE divertor energy fluence to DEMO and ARC. [ABSTRACT FROM AUTHOR]

This letter reports on the efforts carried out at the ASDEX Upgrade tokamak to integrate I-mode plasmas with pellet fueling and to increase the I-mode Greenwald fraction $f_{\mathrm{GW}}$ , two important requirements for any DEMO operational scenario. For the first time, stationary I-mode plasmas have been achieved with pellet fueling and the core Greenwald fraction has been increased up to 0.8. Larger $f_{\mathrm{GW}}$ were not achieved due to technical constraints rather than to a physics-based limit. Pellet-fueled I-mode plasmas exhibit enhanced core and edge density, while core and edge temperature are reduced. Nonetheless, edge normalized gradients remain I-mode-like, namely shallow for the density and steep for the temperature. The I-mode energy confinement time is found to obey two distinct density dependencies: for $f_{\mathrm{GW}}\lt0.4$ it rises with increasing $f_{\mathrm{GW}}$ , while for $f_{\mathrm{GW}} \gt 0.4$ the energy confinement time plateaus with increasing $f_{\mathrm{GW}}$ , or even decreases with $f_{\mathrm{GW}}$ for the pellet-fueled plasmas. Similarities with Ohmic and L-mode energy confinement time dependency on density are discussed.

The I-mode is a natural edge localized mode (ELM)-free regime with H-mode-like improved energy confinement and L-mode-like particle confinement, making it an attractive scenario for future tokamak-based fusion reactors. A kind of low-frequency oscillation has been widely observed, with a frequency between stationary zonal flow and geodesic-acoustic mode (GAM) zonal flow. In EAST, most stationary I-mode shots have such a mode, called edge temperature ring oscillation (ETRO). This mode probably plays an important role in development and maintenance of the I-mode , while investigations are needed to clarify the differences between ETRO and similar mode low-frequency oscillation in other devices, such as limit cycle oscillation (LCO). In this paper, the properties of ETRO are described in detail, including the structure of its magnetic components, its radial propagation characteristics, statistics of its central frequency, a linear analysis of the alternating transition turbulences and a comparison with GAM and LCO. Although some similarities can be found between ETRO and both GAM and LCO, the main features are not identical. ETRO is probably a novel type of finite frequency zonal flow or pressure gradient-induced drift that is unique to the I-mode. It is found that modest fueling can reduce ETRO intensity while maintaining I-mode confinement, suggesting that supersonic molecular beam injection could be used as an effective tool to control ETRO.

Improved energy confinement mode (I-mode) has been observed on the HL-2A tokamak. The I-mode features an edge transport barrier (ETB) in electron temperature and a low confinement mode like edge density. A weakly coherent mode (WCM) is observed in the edge region with the frequency of $f\sim 60{-}160$ kHz and the poloidal wavenumber of ${k_\theta }\sim 0.5{-}2.5{\text{cm}}{^{ - 1}}$ . The maximum of WCM amplitude is located near the top of electron temperature pedestal. A critical value of $E \times B$ velocity shear for triggering the L–I transition has been found, and is much lower than that for triggering the L–H transition. Additionally, ion internal transport barrier (ITB) has been observed in the I-mode. The formation of ion ITB is due to the increase of $E \times B$ velocity shear, leading to the suppression of turbulence. Transport analysis further confirms the existence of electron ETB and ion ITB. The coexistence of electron ETB and ion ITB leads to an improved plasma confinement, which is comparable to that in the high confinement mode, suggesting that I-mode with ITB regimes could be an interesting operation scenario for future fusion devices.

The telecom story in India has been a huge success when we talk of m-commerce. A 100 million plus mobile users is a dream came true for marketers. If that’s not all the number of users is growing by as much as 3 million a month. The number is hugely in favor of m-commerce. So m-commerce is relatively new topic in the Indian market where a lot of research is to be conducted. The article primarily emphasizes on the global perspectives of m – commerce business in Indian market.

Where does platform theory come from? What consequences does it have? This article offers one set of answers to these questions by looking at a body of platform theory that developed in Japan in the 1990s and arguably affected the rollout of internet-enabled mobile phones that were, in turn, models for the iPhone and Android phones several years later. Putting this body of theory in dialogue with managerial and economic theory of the platform from France and the United States, this article suggests an earlier genealogy of platform theory, a development that had immediate and long-lasting consequences for the contemporary media landscape. [ABSTRACT FROM AUTHOR]

This article calls for research on new technologies at a level of analysis where what seems unchanged is salient and yet the newness of the new technology is given due consideration. It demonstrates the value of this approach by analyzing the decentralization of information systems wherein user-generated content eventually provided the unexpected winning solution for service providers who had long struggled in making their content attractive to the public at large. It identifies three stages in the decentralization process: hierarchy (top-down), open-hierarchy (top-down network, bottom-up content creation), and un-order (bottom-up). The analysis indicates that the Achilles’ heel of hierarchical systems is content creation and that creates pressure to move towards more open configurations that allow for user-generated content. The authors suggest that the framework presented in this article will prompt a more sophisticated analysis of the next new technology even if it does not have a similar development pattern. [ABSTRACT FROM PUBLISHER]

Purpose – The aim of this study is to analytically develop a reference model for engineering (i.e. analysis, design, development, evaluation, delivery, maintenance, modification, and management) powerful value networks capable of creating innovative mobile data services. Design/methodology/approach – The paradigm followed is that of design-science research (DSR) which incorporates two main iterative processes: build and evaluate. For building the model (i.e. the design science artifact in this research), the authors followed three iterations: literature review analysis; semi-structured interviews analyzed through content analysis; and examination of real-life case studies. But for evaluating the model, the authors utilized the NTT DoCoMo's i-mode case. Findings – This paper puts forward a novel model for engineering value networks of mobile innovations. This model is composed of seven design constructs and their relationships. The developed model is argued to provide significant utility for telecoms in helping them to identify and design powerful value networks following a systematic and practical approach. Research limitations/implications – The data sources is somewhat limited and the sample is somewhat small which may result in lack of sufficient statistical power. Moreover, the analysis may have overlooked some important concepts and theories related to innovations and value networks. Originality/value – This study contributes to the current body of knowledge about how telecoms can best analyze and design their value networks in an approach that maximizes the potential of developing innovative mobile data services. [ABSTRACT FROM AUTHOR]

Abstract: Japan is leading the world with the adoption of new mobile data services such as Internet services and with a resulting boost in data ARPU (average revenue per user). In the development of these services, many functions have been integrated into mobile handsets, which has resulted in a convergence of, so far, separate consumer electronic devices. This article addresses the following questions: What are the drivers of this process? What could European players, in particular the European policymakers do to catch up? According to our research, a major driver of the process in Japan is tough competition among operators, which in turn is driven by factors such as competition in mobile radio infrastructure. The author arrives at the following conclusions for European policies: (1) There should be more awareness of the Japanese lead, e.g., of the crucial role of Internet push e-mail. (2) Europe could benefit from more operators willing to bear the risk of introducing new technologies. (3) For a successful introduction of infrastructure competition, it could make sense to make spectrum bands available with European-wide licenses. [Copyright &y& Elsevier]

Abstract: This paper attempts to propose a structural model that integrates various factors influencing attitude towards wireless banner ads and intention to access them. This model is applied to empirical data of Japanese mobile users sampled in the greater Tokyo area. First, structural equation modelling is used to test the baseline model. The results show that the model explains mobile users’ perceptual antecedents and consequences well, with all structural paths statistically significant. Second, in the attempt to identify different mobile user groups, a probabilistic cluster analysis is performed. This results in three-cluster groups, consisting of (1) housewives and part-timers, (2) middle-aged white-collar workers and professionals, and (3) students and “parasite singles”. Finally, multigroup analysis is used to examine whether the model operates invariantly across the three-cluster groups. The results indicate significant differences in the paths associated with consumer innovativeness and perceived entertainment between the groups. In closing, managerial implications and future research directions are discussed, while important limitations are recognised. [Copyright &y& Elsevier]

This paper is mainly about cooperation as a collective action in a group context (acting in a position or participating in the performance of a group task, etc.), although the assumption of the presence of a group context is not made in all parts of the paper. The paper clarifies what acting as a group member involves, and it analytically characterizes the "we-mode" (thinking and acting as a group member) and the "I-mode" (thinking and acting as a private person). The main task of the paper is to clarify cooperation, and this is done by dividing cooperation into I-mode and we-mode cooperation. I-mode cooperation relies on the participants' relevantly adjusting their goals toward others' goals and actions to the benefit of all participants. We-mode cooperation basically amounts to joint action in the we-mode. These kinds of cooperation are also connected to the respective kinds of acting as a group member. The paper also investigates the relationship between cooperation and trust and, basically, argues that a two-way connection is involved. [ABSTRACT FROM AUTHOR]

Approximately 40% of the population enjoy access to the Internet via mobile phones in Japan, where user needs have driven developments of the mobile Internet such as “i-mode”. After reviewing mobile Internet services in Japan, this article examines key social and cultural factors of mobile Internet use based on nationally representative surveys focusing on differences between PC and mobile Internet. The results demonstrate that mobile Internet is a more time-enhancing activity while PC Internet is a more time-displacing activity. Additionally, this article discusses unique Japanese cultural factors affecting communication patterns characterized by the high disclosure of subjective self and low disclosure of objective self, which may explain the unique usage patterns of the mobile Internet in Japan. [Copyright &y& Elsevier]

NTT DoCoMo's I-mode system is one of the most successful stories in mobile communication industry. The system has expanded the spectrum for mobile phone users to do more than just phone calls. Although I-mode is primarily used in Japan, its business model and the strategy of doing business may have a profound impact on world's m-commerce in the near future. [ABSTRACT FROM PUBLISHER]