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This paper models the cost efficiency of service function chaining (SFC) in software-defined LTE networks and compares it with traditional LTE networks.

Both the capital expenditure (CAPEX) and operational expenditure (OPEX) of the SFC are quantified using an average Finnish mobile network in 2015 as a reference. The modeling inputs are gathered through semi-structured interviews with Finnish mobile network operators (MNO) and network infrastructure vendors operating in the Finnish market.

The modeling shows that software-defined networking (SDN) can reduce SFC-related CAPEX and OPEX significantly for an average Finnish MNO in 2015. The analysis on different types of MNOs implies that a MNO without deep packet inspection sees the biggest cost savings compared to other MNO types.

Service function investments typically amount to 5-20 per cent of the overall MNO network investments, and savings in SFC may impact highly on the cost structure of a MNO. In addition, SFC acts as both a business interface, which connects the local MNOs with global internet service providers, and as a technical interface, where the 3GPP and IETF standards meet. Thus, the cost efficient operation of SFC may bring competitive advantages to the MNO.

The results show solid basis of network-related cost savings in SFC and contributes to MNOs making cost conscious investment decisions. In addition, the results act as a baseline scenario for further studies that combine SDN with virtualization to re-optimize network service functions.

This research aims to provide a theory-based means for firms to improve customers' likelihood to provide reviews and elicit reviews that are more accurate accounts of customers' consumption experience. The authors also examined the moderating impact of type of review (whether the reviews are anonymous or identified) on the effect of moral identity on the likelihood to provide reviews and accuracy of the reviews.

Data were collected via two experiments (n = 524) in lab sessions. The authors used convenient samples comprised of college students and administrative staff. Study 1 was used to examine the impact of participants' naturally existing moral identity on the likelihood to provide reviews and the accuracy of the reviews provided. Study 2 was used to investigate whether moral identity can be artificially activated or not. Study 2 was also used to test the moderating impact of the type of review on the effect of moral identity (activated vs not activated/control) on likelihood to provide reviews and the accuracy of the reviews provided.

The authors found that moral identity positively impacts the likelihood that customers will agree to provide reviews and the accuracy of the reviews. Also, the type of review moderates the effect of moral identity for those whose moral identity was not activated (i.e. uninfluenced). However, the type of review did not moderate the effect of moral identity when participants' moral identity was activated or primed.

Strategies currently used to elicit online reviews yield low conversion rates or elicit reviews that potential customers do not trust. This paper provides an empirically tested, theory-driven means for managers of digital platforms to improve customer engagement behaviors such as “liking”, tweeting, sharing and product reviews.

Wool, mainly composed of keratin, is a relatively high-grade clothing material. Although woollen textile has the advantages of high wearing comfort and excellent warmth retention property as we have known, its inherent disadvantage of easy pilling has easy puzzled people for a long time. Most of the existing technologies for pilling resistance are not eco-friendly or severely damaged the internal structure of wool.

In this work, a controlled and effective surface treatment method was proposed to controllable micro-dissolution the scale layers of wool with minor damage to its internal structure, thereby improving the anti-pilling property of wool. Thiourea dioxide (TD) is used as a dissolving agent to swell and dissolve wool surface flakes. After TD treatment, the morphology changes of wool fibers were observed by scanning electron microscope (SEM) and methylene blue staining. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to characterize the structural changes of TD wool. At the same time, the anti-pilling properties and wettability of wool fabrics were tested.

The results show that the wool scale layer is destroyed after TD treatment, which reduces the friction between fibers and improves the anti-pilling performance of wool fabrics. The methylene blue-stained images further demonstrate that low concentrations of TD can damage the superficial scale layer of wool without significant loss of strength.

This method is simple, eco-friendly and economical, and opens up a new direction for the surface treatment of wool fabrics.

Privacy scholars appear to struggle in conceptualizing blockchain from a privacy perspective: is it a privacy-enhancing mechanism like differential privacy, a privacy-intruding tool like third-party cookies or a technology orthogonal to the issue of privacy? Blockchain does not seem to neatly fit into any of these buckets that we traditionally use to gauge the privacy implications of information technologies. In this article, the authors argue that blockchain transcends the extant conceptualization of privacy because it modifies the nature of data flow upon which the modern concept of privacy is based.

The authors introduce a conceptualization of blockchain as a new mechanism for data management. Then, following this conceptualization, the authors present a functional review of blockchain, summarizing the features it provides for the data it manages. This review sets up the discussion of how blockchain redefines data flow by separating the power of collection, access and query of data to different entities. After illustrating how this change regrounds privacy concerns in a blockchain system, the authors conclude with a discussion of the recommendations for future privacy research on blockchain.

The authors demonstrate that blockchain, by design, separates three core data-centric operations that are assumed to be inextricably linked in the canonical conceptualization of privacy: the collection, access and query of data. Collection means to capture and then store the data; access means to modify or augment the data and query means the ability to test or verify certain properties of the data (e.g. whether a bank account has a zero balance). Traditionally, any entities that collect data can evidently read, modify or query the same data as they wish. With blockchain, however, an entity that stores the data may not be able to modify the data, yet an entity that cannot even read the data may be able to verify certain properties of the data.

Privacy scholars appear to struggle in conceptualizing blockchain from a privacy perspective: is it a privacy-enhancing mechanism like differential privacy, a privacy-intruding tool like third-party cookies or a technology orthogonal to the issue of privacy? In this article, the authors aim to respond to this important question.

The step effect and support structure generated by the manufacturing process of fused deposition molding parts increase the consumables cost and decrease the printing quality. Multiorientation printing helps improve the surface quality of parts and reduce support, but path interference exists between the printing layer and the layers printed. The purpose of this study is to design printing paths between different submodels to avoid interference when build orientation changed.

Considering support constraint, build orientation sequence is designed for submodels decomposed by model topology. The minimum printing angle between printing layers is analyzed. Initial path through the oriented bounding box is planned and slice interference relationship is then detected according to the projection topology mapping. Based on the relationship matrix of multiorientation slice, feasible path is calculated by directed graph (DG). Final printing path is determined under support constraint and checked by minimum printing angle. The simulation model of the robotic arm is established to verify the accessibility of printing path under the constraint of support and slice.

The proposed method can reduce support structure, decrease volume error and effectively solve the interference problem of the printing path for multiorientation slice.

The method based on projection topology mapping greatly improves the efficiency of interference detection. A feasible path calculated through DGs ensures the effectiveness of the printing path with the constraint of support and slice.

Despite most studies on political ties focusing on the interpersonal relationships between firms and government officials, this study suggests that local party committees (LPCs) create special forms of political ties in China – i.e. organizational political ties. The purpose of this paper is to examine the influences that these organizational political ties have on Chinese firms’ innovative activities.

Drawing upon data based on a nationwide survey of Chinese firms in 2013, this study uses a structural equations model to examine the relationship between LPCs and firms’ innovations.

This study found that LPCs do affect firms’ innovations positively, including both radical innovations and incremental innovations.

By suggesting that LPCs are a form of political tie particular to China – i.e. an organizational political tie – this study’s findings may shed fresh light on the research into political ties in other emerging economies.

Compared to traditional political ties, maintaining the organizational political ties fostered by LPCs benefits firms’ innovations significantly in China, making them less costly and more stable.

This paper aims to study the oxidation kinetics of the nanocrystalline Al ultrathin films. The influence of structure and composition evolution during thermal oxidation will be observed. The reason for the change in the oxidation activation energy on increasing the oxidation temperature will be discussed.

Al thin films are deposited on the silicon wafers as substrates by vacuumed thermal evaporation under the base pressure of 2 × 10⁻⁴ Pa, where the substrates are not heated. A crystalline quartz sensor is used to monitor the film thickness. The film thickness varies in the range from 30 to 100 nm. To keep the silicon substrate from oxidation during thermal oxidation of the Al film, a 50-nm gold film was deposited on the back side of silicon substrate. Isothermal oxidation studies of the Al film were carried out in air to assess the oxidation kinetics at 400-600°C.

The activation energy is positive and low for the low temperature oxidation, but it becomes apparently negative at higher temperatures. The oxide grains are nano-sized, and γ-Al₂O₃ crystals are formed at above 500°C. In light of the model by Davies, the grain boundary diffusion is believed to be the reason for the logarithmic oxidation rate rule. The negative activation energy at higher temperatures is apparent, which comes from the decline of diffusion paths due to the formation of the γ-Al₂O₃ crystals.

It is found that the oxidation kinetics of nanocrystalline Al thin films in air at 400-600°C follows the logarithmic law, and this logarithmic oxidation rate law is related to the grain boundary diffusion. The negative activation energies in the higher temperature range can be attributed to the formation of γ-Al₂O₃ crystal.

This study introduced a focus on work flexibility-worry and intended to test whether work flexibility-worry would weaken the strengthening power of work flexibility-willingness on the relationship between work flexibility-ability and work–family conflict from the perspective of person–situation interaction.

Participants were 924 employees recruited by the snowballing technique. They completed questionnaires about demographics and work flexibility. Multivariate stepwise regression was used to analyze the collected data.

Results showed that work flexibility-ability can reduce work-to-family conflict. However, this effect is most pronounced only among individuals with a high work flexibility-willingness who simultaneously experience low work flexibility-worry.

For organizations that want to provide work flexibility benefits to employees, they should not only pay attention to employees' personal preference for work flexibility but also create a climate in which all employees are allowed to use the flexibility supply without criticism from coworkers and without impacting organizational evaluations, which can benefit employees' functioning in both their work and family roles.

This study clarified the joint role of willingness and worry in predicting the extent to which work flexibility-ability reduces work–family conflict, which helps organizations to better understand the conditions under which work flexibility can better reduce work–family conflict.

In the implementation of large-size additive manufacturing (AM), the large printing area can be established by using the tiled and fixed multiple printing heads or the single dynamic printing head moving in the x–y plane, which requires a layer decomposition after the mesh slicing to generate segmented infill areas. The data processing flow of these schemes is redundant and inefficient to some extent, especially for the processing of complex stereolithograph (STL) models. It is of great importance in improving the overall efficiency of large-size AM technics software by simplifying the redundant steps. This paper aims to address these issues.

In this paper, a method of directly generating segmented layered infill areas is proposed for AM. Initially, a vertices–mesh hybrid representation of STL models is constructed based on a divide-and-conquer strategy. Then, a trimming–mapping procedure is performed on sliced contours acquired from partial surfaces. Finally, to link trimmed open contours and inside-signal square corners as segmented infill areas, a region-based open contour closing algorithm is carried out in virtue of the developed data structures.

In virtue of the proposed approach, the segmented layered infill areas can be directly generated from STL models. Experimental results indicate that the approach brings us the good property of efficiency, especially for complex STL models.

The proposed approach can generate segmented layered infill areas efficiently in some cases.

The region-based layered infill area generation approach discussed here will be a supplement to current data process technologies in large-size AM, which is very suitable for parallel processing and enables us to improve the efficiency of large-size AM technics software.

This paper aims to reschedule the freight train timetable in case of disturbance to restore the train services as soon as possible.

Hence, an integer linear programming model for the real-time freight heavy-haul railway traffic management is developed in case of large primary delays caused by the delayed cargos loading. The proposed model based on the alternative graph at the microscopic level depicts the freight train movements in detail. Multiple dispatching measures such as re-timing and re-ordering are taken into account. Moreover, two objective functions, namely, the total final delays and the consecutive delays, are minimized in the freight trains dispatching problem.

Finally, a real-world computational experiment based on the Haolebaoji-Ji’an freight heavy-haul railway is implemented. The results of all disrupted cases are obtained within 10 s. The results give insight into that the consecutive delays are more than the total final delays when the same disrupted situation and the consecutive or total final delays increase as the primary delays increase.

An integer linear programming model based on the alternative graph for the real-time freight heavy-haul railway traffic management is developed in case of large primary delays caused by the delayed cargos loading. The method can be developed as the computer-aided tool for freight train dispatchers.