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This paper describes the architecture of using the Mobile Agent and ACID (Atomicity, Consistency, Isolation and Durability) in Mobile e-Learning (mLearning). In the coming years, there will be an incremental amount of mobile learning experiments for the purpose of implementing mobile ICTs into mainstream education. In this article, the Replication Agent and Snapshot Agent architecture is proposed as an effective way to overcome the problem of heavy loading on the limited bandwidth used in wireless transmission for mobile learning environment merge replication process. The implementation of mobile agents as middleware for mLearning environment is to provide database replication between learners and off-site database e.g., Knowledge Management Centre's (KMC) databases using handheld devices. The approach using the combination of both these agents plays an important role in wireless transmission. It provides an intelligent solution to the limitation of the wireless bandwidth by lowering the bandwidth taken up during the bursts of mobile transactions. In this proposed technique, a mLearning database is determined as a Snapshot publisher where a compact edition of files and information is generated at the snapshot location which resides on the central database server. Learners may retrieve quick bursts of information through mobile applications wirelessly. The Replication Agent offers the flexibility to move from one site (user) to another (central database) for essential data synchronization. In order to provide learners with appropriate courses, a prototype on mLearning platform supporting three-layered structure and device adapting was put forward. The architecture of the platform discussed in this study as the mobile agent approach would facilitate more widespread use of mLearning, including in courses discussions between learners and academicians.

The Kirkendall void had been a well-known issue for long-term reliability of semiconductor interconnects; while even the KVs exist at the interfaces of Cu and Sn, it may still be able to pass the condition of unbias long-term reliability testing, especially for 2,000 cycles of temperature cycling test and 2,000 h of high temperature storage. A large number of KVs were observed after 200 cycles of temperature cycling test at the intermetallic Cu₃Sn layer which locate between the intermetallic Cu₆Sn₅ and Cu layers. These kinds of voids will grow proportional with the aging time at the initial stage. This paper aims to compare various IMC thickness as a function of stress test, the Cu₃Sn and Cu₆Sn₅ do affected seriously by heat, but Ni₃Sn₄ is not affected by heat or moisture.

The package is the design in the flip chip-chip scale package with bumping process and assembly. The package was put in reliability stress test that followed AEC-Q100 automotive criteria and recorded the IMC growing morphology.

The Cu₆Sn₅ intermetallic compound is the most sensitive to continuous heat which grows from 3 to 10 µm at high temperature storage 2,000 h testing, and the second is Cu₃Sn IMC. Cu₆Sn₅ IMC will convert to Cu₃Sn IMC at initial stage, and then Kirkendall void will be found at the interface of Cu and Cu₃Sn IMC, which has quality concerning issue if the void’s density grows up. The first phase to form and grow into observable thickness for Ni and lead-free interface is Ni₃Sn₄ IMC, and the thickness has little relationship to the environmental stress, as no IMC thickness variation between TCT, uHAST and HTSL stress test. The more the Sn exists, the thicker Ni₃Sn₄ IMC will be derived from this experimental finding compare the Cu/Ni/SnAg cell and Ni/SnAg cell.

The research found that FCCSP can pass automotive criteria that follow AEC-Q100, which give the confidence for upgrading the package type with higher efficiency and complexities of the pin design.

This result will impact to the future automotive package, how to choose the best package methodology and what is the way to do the package. The authors can understand the tolerance for the kind of flip chip package, and the bump structure is then applied for high-end technology.

The overall three kinds of bump structures, Cu/Ni/SnAg, Cu/SnAg and Ni/SnAg, were taken into consideration, and the IMC growing morphology had been recorded. Also, the IMC had changed during the environmental stress, and KV formation was reserved.

Teachers of primary education experience high levels of stress but lack rational coping strategies to reduce their work stress. The paper develops a value stream mapping for education approach and examines its use as a rational coping strategy for teams of teachers and other employees to overcome work-related stressors.

The research process consists of two phases. First, a value stream mapping approach for education is developed, based on literature research. Next, the approach is validated in an action research study to reduce work stress of teachers in educational services. The processes that have been selected by the teachers relate to coping with increased variety, long and uncertain throughput times and unclear specifications.

Value stream mapping for education (VSM4EDU) is a well-structured improvement method based on principles of visualization, participation and process thinking, which helps teachers without background in lean thinking to analyse their processes. Using this method has enabled the team to develop rational coping strategies to reduce their work-related stress.

VSM4EDU has been validated using action research at a single school, which implicates deep insight, but further testing at other schools is welcome. Moreover, VSM4EDU has not been used to develop a future state map.

Value stream mapping is useful in educational settings as long as the educational context is respected in the approach.

VSM4EDU empowers teachers and helps to develop co-operation in teams.

The validation of value stream mapping for education is well-documented and original.

To explore how and why the social structures of strategic partnerships are shaped by actors and how these interrelate with a team's interpersonal relationships over time. Grasping the complexity of this interplay is essential if we want to comprehend what actually goes on in these partnerships and understand why actors often disengage from them.

In three cases, 14 in-depth interviews were held with knowledgeable actors about important events and activities that influenced the relationships between partners. Interview data were triangulated with journals kept by the lead author, who participated as an engaged scholar in the three cases. Because this study took an interdisciplinary approach, new insights could evolve from the multi-level analysis.

Trust has a moderating effect on the relation between open-book accounting and the degree of control a dominant party wants to exercise. When the level of control is raised, this can signal distrust to the other partners, which can harm the relationship. When partners feel more dependent on each other's capabilities to reach their long-term goals, the parties seem to be less likely to put the blame on one of the partners in the case of undesirable events.

Managers should be aware of their power position and acknowledge the effects of power on their relationships. If long-term and close collaboration does not emerge in their partnership, it may be due to how they use their power position.

Thanks to the interdisciplinary approach, this is the first study that shows the significance of trust and power in maintaining strategic partnerships in the construction industry, and how trust can affect the financial rules of actors.

Allocation of complex crowdsourcing tasks, which typically include heterogeneous attributes such as value, difficulty, skill required, effort required and deadline, is still a challenging open problem. In recent years, agent-based crowdsourcing approaches focusing on recommendations or incentives have emerged to dynamically match workers with diverse characteristics to tasks to achieve high collective productivity. However, existing approaches are mostly designed based on expert knowledge grounded in well-established theoretical frameworks. They often fail to leverage on user-generated data to capture the complex interaction of crowdsourcing participants’ behaviours. This paper aims to address this challenge.

The paper proposes a policy network plus reputation network (PNRN) approach which combines supervised learning and reinforcement learning to imitate human task allocation strategies which beat artificial intelligence strategies in this large-scale empirical study. The proposed approach incorporates a policy network for the selection of task allocation strategies and a reputation network for calculating the trends of worker reputation fluctuations. Then, by iteratively applying the policy network and reputation network, a multi-round allocation strategy is proposed.

PNRN has been trained and evaluated using a large-scale real human task allocation strategy data set derived from the Agile Manager game with close to 500,000 decision records from 1,144 players in over 9,000 game sessions. Extensive experiments demonstrate the validity and efficiency of computational complex crowdsourcing task allocation strategy learned from human participants.

The paper can give a better task allocation strategy in the crowdsourcing systems.

Since the last few decades, Artificial Neural Networks have been the center of attraction of a large number of researchers for solving diversified problem domains. Due to its distinguishing features such as generalization ability, robustness and strong ability to tackle nonlinear problems, it appears to be more popular in financial time series modeling and prediction. In this paper, a Pi-Sigma Neural Network is designed for foretelling the future currency exchange rates in different prediction horizon. The unrevealed parameters of the network are interpreted by a hybrid learning algorithm termed as Shuffled Differential Evolution (SDE). The main motivation of this study is to integrate the partitioning and random shuffling scheme of Shuffled Frog Leaping algorithm with evolutionary steps of a Differential Evolution technique to obtain an optimal solution with an accelerated convergence rate. The efficiency of the proposed predictor model is actualized by predicting the exchange rate price of a US dollar against Swiss France (CHF) and Japanese Yen (JPY) accumulated within the same period of time.

This paper comprehensively addresses the influence of chopped strand mat glass fiber-reinforced polymer (GFRP) patch configurations such as geometry, dimensions, position and the number of layers of patches, whether a single or double patch is used and how well debonding the area under the patch improves the strength of the cracked aluminum plates with different crack lengths.

Single-edge cracked aluminum specimens of 150 mm in length and 50 mm in width were tested using the tensile test. The cracked aluminum specimens were then repaired using GFRP patches with various configurations. A three-dimensional (3D) finite element method (FEM) was adopted to simulate the repaired cracked aluminum plates using composite patches to obtain the stress intensity factor (SIF). The numerical modeling and validation of ABAQUS software and the contour integral method for SIF calculations provide a valuable tool for further investigation and design optimization.

The width of the GFRP patches affected the efficiency of the rehabilitated cracked aluminum plate. Increasing patch width WP from 5 mm to 15 mm increases the peak load by 9.7 and 17.5%, respectively, if compared with the specimen without the patch. The efficiency of the GFRP patch in reducing the SIF increased as the number of layers increased, i.e. the maximum load was enhanced by 5%.

This study assessed repairing metallic structures using the chopped strand mat GFRP. Furthermore, it demonstrated the superiority of rectangular patches over semicircular ones, along with the benefit of using double patches for out-of-plane bending prevention and it emphasizes the detrimental effect of defects in the bonding area between the patch and the cracked component. This underlines the importance of proper surface preparation and bonding techniques for successful repair.

Projecting the population distribution in geographical regions is important for many applications such as launching marketing campaigns or enhancing the public safety in certain densely populated areas. Conventional studies require the collection of people’s trajectory data through offline means, which is limited in terms of cost and data availability. The wide use of online social network (OSN) apps over smartphones has provided the opportunities of devising a lightweight approach of conducting the study using the online data of smartphone apps. This paper aims to reveal the relationship between the online social networks and the offline communities, as well as to project the population distribution by modeling geo-homophily in the online social networks.

In this paper, the authors propose the concept of geo-homophily in OSNs to determine how much the data of an OSN can help project the population distribution in a given division of geographical regions. Specifically, the authors establish a three-layered theoretic framework that first maps the online message diffusion among friends in the OSN to the offline population distribution over a given division of regions via a Dirichlet process and then projects the floating population across the regions.

By experiments over large-scale OSN data sets, the authors show that the proposed prediction models have a high prediction accuracy in characterizing the process of how the population distribution forms and how the floating population changes over time.

This paper tries to project population distribution by modeling geo-homophily in OSNs.

Despite many efforts within organizations toward business process orientation (BPO), research on real-world experiences remains in its infancy. The purpose of this paper is to redress the existing knowledge gap by analyzing a Swedish public housing company that has made notable effects regarding BPO and to explore lessons learned from the BPO journey (from 1998 to 2013).

The point of departure is principles in the BPO foundation, principles of successful BPM and effects in empirically based literature. The reconstruction of the narrative case study describes milestones and critical junctions, as well as effects based on quantitative and qualitative data.

Effects in BPO are demonstrated in terms of higher customer satisfaction, increased innovative ability, improved operational performance, higher employee satisfaction and, as a result of these, increased profitability. Theoretical constructs with implications for the theory building on BPO are suggested in a three-layer management framework – with capabilities and abilities emerging from the case study used as an illustrative example.

Lessons are learned regarding critical practices related to advancement in BPO. A strategy-building process based on eight design propositions is suggested to define the pre-conditions for BPO in an organization.

This is the first longitudinal case study to provide a comprehensive view and detailed insights of a BPO journey and top management performance toward a business process-oriented organization. Practitioners and BPM community get valuable insights into how the temporality and the context shape the BPO maturity process in terms of new organizational structure and roles during the journey.