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The purpose of this paper is to investigate the explosive performance and explosion damage mechanism of T-beam bridge structure.

On the basis of the existing specification, two T-beam bridge models were designed and fabricated. Test specimens of different explosive dosage and different blast height were carried out. The mechanical process, failure mode, blast damage model, damage identification mechanism and blast evolution law and quantitative evaluation were taken into account.

The results revealed that the web plate fracture failure is the key to the unstable failure of the whole T-beam bridge. The explosion failure phenomenon and blast damage evaluation criterion of RC T-beam bridge was divided into five stages: the original cracks stage of concrete material (D = 0 ∼ 0.1), the fractures initiation stage of concrete material (D = 0.1 ∼ 0.3), the stable expansion stage of cracks in concrete material (D = 0.3 ∼ 0.55), the unstable expansion stage of cracks in concrete material (D = 0.55 ∼ 0.8), the explosion fracture of steel bars and the overall instability and damage of the bridge (D = 0.8 ∼ 1.0), which can also be described as basically intact, slight damage, moderate damage, severe damage and collapsed.

The research result will provide basis for the antiknock evaluation and damage repair technical specifications of the RC T-beam bridge.

The research results of damage evaluation serve as a basis for damage repair and reinforcement of bridge structures after explosion.

Many bike rental organizations permit customers to pick-up bikes from one bike station and return them at a different one. However, this service may result in bike imbalance, as bikes may accumulate in stations with low demand. To overcome the imbalance problem, this paper aims to develop a decision model to minimize the total costs of unmet demand and empty bike transport by determining bike fleet size, deployments and the vehicle routing schedule for bike transports.

This paper developed a constrained mixed-integer programming model to deal with this bike imbalance problem. The proposed model belongs to the non-deterministic polynomial-time (NP)-hard problem. This paper developed a two-phase heuristic approach to solve the model. In Phase 1, the approach determines fleet size, deployment level and the number of satisfied demands. In Phase 2, the approach determines the routing schedule for bike transfers.

Computational results show the following results that the proposed approach performs better than General Algebraic Modeling System (GAMS) in terms of solution quality, regardless of problem size. The objective values and the fleet size of rental bikes allocated increase as the number of rental stations increases. The cost of transportation is not directly proportional to the number of bike stations.

The authors provide an integrated model to simultaneously deal with the problems of fleet sizing, empty-resource repositioning and vehicle routing for bike transfer in multiple-station systems, and they also present an algorithm that can be applied to large-scale problems which cannot be solved by the well-known commercial software, GAMS/CPLEX.

The historical data usually consist of overlapping reports, and these reports may contain inconsistent data, which may return incorrect results of a query search. Moreover, users who issue the query may not learn of this inconsistency even after a data cleaning process (e.g. schema matching or data screening). The inconsistency can exist in different types of data, such as temporal or spatial data. Therefore, this paper aims to introduce an information fusion method that can detect data inconsistency in the early stages of data fusion.

This paper introduces an information fusion method for multi-robot operations, for which fusion is conducted continuously. When the environment is explored by multiple robots, the robot logs can provide more information about the number and coordination of targets or victims. The information fusion method proposed in this paper generates an underdetermined linear system of overlapping spatial reports and estimates the case values. Then, the least squares method is used for the underdetermined linear system. By using these two methods, the conflicts between reports can be detected and the values of the intervals at specific times or locations can be estimated.

The proposed information fusion method was tested for inconsistency detection and target projection of spatial fusion in sensor networks. The proposed approach examined the values of sensor data from simulation that robots perform search tasks. This system can be expanded to data warehouses with heterogeneous data sources to achieve completeness, robustness and conciseness.

Little research has been devoted to the linear systems for information fusion of tasks of mobile robots. The proposed information fusion method minimizes the cost of time and comparison for data fusion and also minimizes the probability of errors from incorrect results.

In the absence of well-developed, formal institutional frameworks, informal network-based strategies have been argued to be especially viable in emerging economies. However, some empirical research has challenged these earlier theoretical arguments. In light of new evidence, this chapter develops a contingency perspective differentiating firms' networks as strong ties and weak ties. It suggests that while strong-tie networks are typically found during the early phase of institutional transitions, weak-tie networks are more likely to be developed and leveraged during the late phase of transitions. The upshot is that as the performance benefits of strong ties decline during institutional transitions, emerging weak ties' impact on firm performance is likely to increase.

The purpose of this paper is to offer a theoretical and empirical understanding of how social ties affect innovation behavior and new product performance in Turkey, which is an emerging economy where high levels of economic and political uncertainties exist.The authors examine whether innovation behavior binds the political and business ties of the firm to new product performance. They also examine if these effects are contingent on variations in the institutional environment and market environment.

Structural equation modeling and mediation analyses were used on a sample of 344 small- and medium-sized enterprises in Istanbul.

Business ties are positively related to exploratory innovation behavior and political ties hamper such behavior. The authors also show that government support hinders firms’ disruptive innovation while encouraging incremental innovation behavior. The authors further demonstrate that the positive and indirect relation of business ties to new product performance through exploratory and exploitative innovation is largely insensitive to changes in market and institutional environments. Political ties are negatively (positively) and indirectly related to new product performance through exploratory (exploitative) innovation.

Managers should choose the form of their personal interactions (political and/or business) based on the type of innovation that is being pursued. Additionally, managers should consider both the institutional environment and the market environment as important contingencies in their decision of whether to invest resources in developing social ties to build innovation behavior.

The authors offer a deeper perspective of how social ties in emerging economies affect new product performance by considering exploratory and exploitative innovation behavior as mediating mechanisms. These mediating effects are conditional on institutional and market environments.

The purpose of this study is to reconcile the positive, non-significant and even negative effects of guanxi on firm performance from two aspects. First, it explores the linear and curvilinear relationships between guanxi and distinct performance dimensions. Second, it examines the moderating effects of both exchange-related behavioral risk (reflected by contract enforcement in this study) and market-related environmental risk (reflected by market turbulence in this study) on the above relationship.

Based on data for 206 samples collected from distributors of house furnishings, computers and their components, a moderated regression is used to test the hypotheses.

The empirical test generally supports the conceptual model and demonstrates three findings. First, guanxi has a linear, positive effect on financial performance and an inverted U-shaped effect on strategic performance. Second, contract enforcement decreases the effect of guanxi on financial performance and enhances its effect on strategic performance. Third, market turbulence enhances the effect of guanxi on financial performance and weakens its effect on strategic performance.

First, this study collects data only from China. Future studies should collect data from other emerging markets to allow for either model validation or cross-country comparisons. Second, the data come only from buyers, and suppliers’ viewpoints are not included. Third, in addition to contract enforcement and market turbulence, other important contingencies should be considered in the guanxi–performance link.

The results provide important implications for managers to manage guanxi in an emerging economy. Managers should be very clear about their primary goal (i.e. pursuing short-term financial revenue or long-term strategic targets); next, they should understand how to match guanxi with various levels of contract enforcement and market turbulence to achieve that goal.

First, prior research has documented guanxi’s role in channel relationships, but it has not achieved consistent conclusions. Second, although existing studies have analyzed the contingencies of guanxi at the firm level, market level and institutional level, another important contingency “the dyadic relationship condition” is rarely considered. Third, although the extant research has realized the value of guanxi contingent on various market conditions, conflicting views exist. This study contributes by addressing these issues.

From the standpoint of a policy maker who has access to a number of expert forecasts, the uncertainty of a combined or ensemble forecast should be interpreted as that of a typical forecaster randomly drawn from the pool. This uncertainty formula should incorporate forecaster discord, as justified by (i) disagreement as a component of combined forecast uncertainty, (ii) the model averaging literature, and (iii) central banks’ communication of uncertainty via fan charts. Using new statistics to test for the homogeneity of idiosyncratic errors under the joint limits with both T and n approaching infinity simultaneously, the authors find that some previously used measures can significantly underestimate the conceptually correct benchmark forecast uncertainty.

Grounded in strategic choice and resource-based views, this study aims to investigate the antecedents and consequences of relational strategic emphasis of foreign subsidiaries operating in Thailand. Four types of relational strategies were identified with associated differential performance outcomes.

Data collected via self-administered surveys from a diverse sample of 168 foreign subsidiaries were analyzed in two stages. First, multinomial logistic regression was used to test whether resource-bridging capability, nonmarket-based assets and market-based assets were significant predictors of relational strategy type. Then, multivariate analysis of variance was used to determine whether the four relational strategy types differed in their strategic performance and financial performance.

The three resource-based motives are significant predictors of relational strategy. Firms adopting the “dual-relational” strategy tend to have the highest level of resource-bridging capability and nonmarket-based assets while firms pursuing the “business-oriented” strategy are likely to possess a higher level of market-based assets. Extensive reliance on relational ties enables foreign subsidiaries to achieve a much higher level of strategic and financial performance than those that chose to only rely on transactional or contractual relations.

Foreign subsidiaries operating in emerging markets characterized by an unstable market environment have to establish good relationships with buyers, suppliers and distributors, as well as government agents.

Using a juxtaposition of political and business ties, a typology of the relational strategy was conceptualized. This study extends non-market strategy research by investigating the relationship between resource and capability in the choice of relational strategy. Diverse degrees of political and business ties show different impacts on strategic and financial performances.

Compared with the traditional printed circuit board (PCB) drilling process, the technology of drilling IC substrate is facing more problems, such as much smaller hole diameter, more intensive hole space, thinner sheet and more complicated materials are drilled in process. Moreover, the base material of IC substrate is different from traditional PCB, more kinds of fillers added in IC substrate which make the drill worn seriously during drilling process. Micro-drills wear and micro holes quality are the most important questions when drilling IC substrate so far. Wear morphology of micro-drill, holes wall roughness and hole location accuracy are researched in this paper. The influence factors of micro-drills wear and micro holes quality are also studied in this drilling process. The paper aims to discuss these issues.

Two drills with same structure and different diameter are used to drill different stacks of IC substrate and drill different holes in this paper. There are four experiments made and the drilling parameters including spindle speed (n), feed rate (v_f) and retraction speed (v_r) are recommended by drill manufacturing company. Wear morphologies of drill are observed, holes wall roughness (R_max) and holes location accuracy (C_pk) are measured in this paper. Analyzing the main factors influence on drill wear, holes wall roughness and holes location accuracy through these experiments.

The micro-drills of IC substrate wear more severely compared with other material of PCB through the experimental results in this paper. Drill diameter has influence on micro-drill wear when drilling IC substrate, the smaller of drill is, the more severely of micro-drill wears. Drill diameter affect the holes wall roughness too, the holes wall roughness of larger holes is better than smaller one in a certain range. The drilled holes number also has influence on micro-drills wear, holes wall roughness and holes location accuracy. The more drilled holes, the seriously of micro-drills wear, and the worn drill would destroy the hole quality. Therefore, the more drilled holes lead the bad holes wall roughness and holes location accuracy in this paper. In addition, stacks of IC substrate affect much on the holes location accuracy, the more stacks, the worse holes location accuracy.

Chinese Mainland is obviously lagging behind in technology and manufacturer of IC substrate which is incompatible with the nation circumstances. There is few research of drilling IC substrate in China and research data are lacking so far. It is most necessary to improve the technology level of drilling IC substrate in China. In order to reduce the wear of micro-drills and improve the quality of micro-holes, many experimental tests about drilling IC substrate are researched in this paper.