ALLIANCE PORTFOLIO CONFIGURATION, KNOWLEDGE DEVELOPMENT, AND INNOVATION: THEORETICAL FRAMEWORK AND EMPIRICAL EVIDENCE

Shichun Xu,Erin Cavusgil 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

As companies develop more and more collaborative inter-firm relationships with others on new product development, successful configuration and management of R&D alliance portfolios becomes even more challenging. This paper seeks to understand how different characteristics of a firm’s R&D alliance portfolio influence its ability to acquire external knowledge and how knowledge acquisition in turn influences the firm’s innovation outcomes. The central argument is that a firm’s R&D alliance portfolio strategy entails both knowledge structure benefit and relational benefit. Firms seek to achieve these two different types of benefits by bringing in different desired partners. As a result, a firm’s choice or preferences for different types of R&D alliance partners influence both the scope of external knowledge it is exposed to (knowledge structure benefit) as well as the partner’s willingness to share and the focal firm’s ability to absorb and learn from its partners (relational benefit). While certain strategies may offer firms’ the opportunity to achieve both types of benefits simultaneously, other strategies may force firms to choose one benefit over the other. In order to exploit the value of the acquired knowledge acquired from external partners, firms need to further apply this knowledge to come up with innovative products or services. Literature has further classified new product offerings into radical vs. incremental innovations based on their innovativeness and customer benefit increase. Due to the different characteristics and knowledge requirements for radical vs. incremental innovation, we investigate how different dimensions play differential roles in the development process of these two types of innovation. We empirically tested our hypothesis in the context of pharmaceutical industry with a panel data of 64 firms over 15 years. The statistical results largely support our hypothesis.

Simulation of Conceptual Designs of a Three-Surface Stealth Strike Fighter

Kuizhi, Yue,ShiChun, Chen,Wenlin, Liu,Dazhao, Yu The Korean Society for Aeronautical and Space Scie 2014 International Journal of Aeronautical and Space Sc Vol.15 No.4

A conceptual design of a three-surface strike fighter was studied and stealth performance was taken into account to enhance survivability and battle effectiveness. CATIA was used to design the aircraft's three-dimensional prototype model and the weapon carriage arrangement was also studied. The aircraft's RCS characteristics and distributions under X, S, C, and L bands were simulated using the RCSPlus software, which is based on the PO method. Pressure and velocity distributions of the flow field were also simulated using CFD. A turbulence model was based on standard $k-{\varepsilon}$ function and N-S functions were used during the CFD computation. Lift coefficients, drag coefficients, and lift-to-drag ratio were obtained by aerodynamic simulation. The results showed that: (1) the average value of head-on RCS between ${\pm}30^{\circ}$ is below -3.197 dBsm, and (2) the lift coefficient is 0.34674, the drag coefficient is 0.04275, and the lift-to-drag ratio is 8.11087 when the attack angle is $2.5^{\circ}$.

Dynamic Parameters Updating of Earth-rock Dams Based on Modal Parameter Identification

Maohua Wang,Shichun Chi,Zhenping Liu 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

The reasonable selection of dynamic parameters of earth-rock dams is very important for the seismic safety assessment of dams. Because of the size effects, the parameters acquired from the indoor test may additionally no longer exactly reflect the real dynamic characteristics of the dam. Therefore, it is essential to correct and update the dynamic parameters in accordance to the actual seismic dynamic characteristics of the dam. In this paper, by combining the Covariance-driven stochastic subspace identification (SSI-COV) method and the multiple population genetic algorithm (MPGA), an optimization and updating method for the dynamic parameters of earth-rock dams based on modal parameter identification is presented. The collected weak earthquake records of the dam allowed the modal parameters (the natural frequencies and mode shapes) identification based on SSI-COV method. The optimization updated is performed using the MPGA, which can obtain the optimal values of dynamic parameters of the dam and has good robustness within the optimization range of the numerical model. A typical numerical example is given to exhibit the feasibility and effectiveness of the presented method. Then the dynamic parameters of Liyutan Dam are updated by the proposed method according to the weak earthquake records, and the accuracy and applicability of the updated parameters were further verified by the strong earthquake records. The results show that the method proposed in this paper can provide a good idea for the calibration of dynamic parameters of earth-rock dams and has well practical engineering value.

HOW DOES LOCATION BASED MARKETING AFFECT MOBILE RETAIL REVENUES? THE COMPLEX INTERPLAY OF TACTIC, DEVICE AND USER TYPE

Syagnik Banerjee,Shichun Xu,Scott D. Johnson 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

By increasing awareness of product offers and availability in the consumer’s proximity, Location Based Marketing (LBM) increases relevance of placed advertisements. However, depending on how it is executed, such advertising can also be perceived as intrusive, irritating, or even violating consumer’s privacy. Existing knowledge does not offer clear directions for retailers, who are keen to know of LBM’s effectiveness on sales. In this paper, authors investigate the effects of LBM on application (app) driven revenues of 116 major mobile retailers from around the globe. In particular, we examine the contingency effects of the roles of device as well as privacy needs of the brand audience. Findings reveal that effects of LBM on app-based revenues vary by tactic (inbound vs. outbound), type of device (Tablet vs. Phone), and user type based on brand of app (Android vs. Apple). Overall, this research identifies critical factors for retailers to consider, in order to best monetize their location based efforts. Contributions of the analysis and managerial implications are discussed.

Detection of Inhibitors of Phenotypically Drug-tolerant Mycobacterium tuberculosis Using an In Vitro Bactericidal Screen

Ian M. Bassett,Shichun Lun,William R. Bishai,Haidan Guo,Joanna R. Kirman,Mudassar Altaf,Ronan F. O’Toole 한국미생물학회 2013 The journal of microbiology Vol.51 No.5

Many whole cell screens of chemical libraries currently in use are based on inhibition of bacterial growth. The goal of this study was to develop a chemical library screening model that enabled detection of compounds that are active against drug-tolerant non-growing cultures of Mycobacterium tuberculosis. An in vitro model of low metabolically active mycobacteria was established with 8 and 30 day old cultures of M. smegmatis and M. tuberculosis, respectively. Reduction of resazurin was used as a measure of viability and the assay was applied in screens of chemical libraries for bactericidal compounds. The model provided cells that were phenotypically-resilient to killing by first and second-line clinical drugs including rifampicin. Screening against chemical libraries identified proteasome inhibitors, NSC310551 and NSC321206, and a structurally-related series of thiosemicarbazones,as having potent killing activity towards aged cultures. The inhibitors were confirmed as active against virulent M. tuberculosis strains including multi- and extensively-drug resistant clinical isolates. Our library screen enabled detection of compounds with a potent level of bactericidal activity towards phenotypically drug-tolerant cultures of M. tuberculosis.

Grinding Marks on Ultra-Precision Grinding Spherical and Aspheric Surfaces

Bing Chen,Bing Guo,Shichun Li,Zhaohui Deng,Qingliang Zhao 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.4 No.4

Grinding marks are regard as a great obstacle to manufacture spherical and aspheric surfaces with higher surface quality, lower energy and wastage. The scallop-height was studied for optimizing the grinding parameters firstly to reduce its effect on grinding marks. Secondly, the expression of grinding points distribution was established to characterize the grinding marks caused by the radial run-out of grinding wheel. And then, the aspheric grinding experiments of monocrystalline silicon were carried out to investigate the influence of grinding marks on surface quality. The experiments revealed that the remarkable grinding marks with patterned grinding points distribution would cause more fractures and roughness, deeper grooves, and more inhomogeneous surface quality compared with the weak grinding marks. The discriminating standard of grinding marks was established, and the grinding parameters were optimized for homogenizing the grinding points distribution by this discriminating standard to reduce the grinding marks in actual grinding process. Finally, the large size infrared lens was ground with high surface quality by the optimized grinding parameters, and the results of surface quality demonstrate that the discriminating standard was effective. This research provides references and ideas for grinding aspherical surface with high surface quality and efficiency, low energy and wastage.

Simulation of Conceptual Designs of a Three-Surface Stealth Strike Fighter

Yue Kuizhi,Chen ShiChun,Liu Wenlin,Yu Dazhao 한국항공우주학회 2014 International Journal of Aeronautical and Space Sc Vol.15 No.4

A conceptual design of a three-surface strike fighter was studied and stealth performance was taken into account to enhance survivability and battle effectiveness. CATIA was used to design the aircraft’s three-dimensional prototype model and the weapon carriage arrangement was also studied. The aircraft’s RCS characteristics and distributions under X, S, C, and L bands were simulated using the RCSPlus software, which is based on the PO method. Pressure and velocity distributions of the flow field were also simulated using CFD. A turbulence model was based on standard k-ε function and N-S functions were used during the CFD computation. Lift coefficients, drag coefficients, and lift-to-drag ratio were obtained by aerodynamic simulation. The results showed that: (1) the average value of head-on RCS between ±30° is below -3.197 ㏈sm, and (2) the lift coefficient is 0.34674, the drag coefficient is 0.04275, and the lift-to-drag ratio is 8.11087 when the attack angle is 2.5°.

An Application of BP Neural Network to the Prediction of Compressive Strength in Circular Concrete Columns Confined with CFRP

Khalil AL-Bukhaiti,Liu Yanhui,Zhao Shichun,Hussein Abas 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

The neural network comprises many neurons with extensive interconnections operatingparallel and performing specific functions. This paper establishes a BP neural networkprediction model for the compressive strength of CFRP-confined concrete based on a largenumber of experimental data to study the predictive ability of the BP neural network on thecompressive strength of CFRP-confined concrete and the output performance of the neuralnetwork model. The model is based on a BP neural network that has been trained using manyexperimental data. An investigation is being conducted on the effect of different datacombinations on the accuracy of the predictions made by the neural network model. Thehigh-precision BP network model is created into generic and simplified formulae for applicationconvenience. These formulas are developed based on the theory of neural networks. Theneural network models' findings and the empirical formulae for making predictions arecompared and discussed. The BP neural network accurately predicts the compressive strengthof CFRP-confined concrete, with over 90% of its data points having less than 15% error. Incomparison, the regression model shows less accuracy, with less than 70% of its data pointshaving an error within 15%. Compared to traditional regression models, the simple linearequation derived using Purelin instead of Sigmoid as the transfer function only adds a constantterm. The average value of prediction/test results is 1.011. The analysis results show that BPneural network can extract the input and output parameters' data information well and obtaina high-accuracy prediction model. The coefficient of variation is 0.112, which indicates thatthe prediction accuracy and stability are greater than average.

Experimental Study on Existing RC Circular Members Under Unequal Lateral Impact Train Collision

Khalil AL-Bukhaiti,Liu Yanhui,Zhao Shichun,Hussein Abas,Xu Nan,Yang Lang,Yan Xing Yu,Han Daguang 한국콘크리트학회 2022 International Journal of Concrete Structures and M Vol.16 No.5

With the fast growth of high-speed rail in recent years, derailment has become the first hidden danger of high-speed rail transportation. The high-speed train passes near the station building. So the train may derail and hit the station building. Building a high-speed railway station usually uses a reinforced concrete structure. As a result of high impact energy on the impact body, the reinforced concrete (RC) member may fail; the impact point is near the member's foot; the structural member's constraint can be considered fixed support. This paper investigates the dynamic behavior of four types of circular reinforced concrete members under unequal lateral impact loads. The RC member's failure mechanism and dynamic response addressed the significance of unequal lateral impact load. The usual circular reinforced concrete members are used as the model to perform the drop-weight impact test. The specimens' crack pattern, failure mechanism, impact, deflection, and strain time–history curves are obtained. Findings show that between the impact point and the adjacent support, shear fractures occur that fail in shear mode. Shear cracks are based on impact velocity, longitudinal reinforcement ratio, and stirrup ratio. One type is more destructive to members and nodes. A shear fracture occurs when a longitudinal reinforcement fractures towards the closer support. The effects of impact velocity, longitudinal reinforcement ratio, and stirrup ratio on the dynamic impact response are studied. The experimental results may help improve structural member impact resistance. The critical section (right side) computed the static shear resistance using shear force, whereas the maximum external load resistance determines static bending moment resistance. Understanding how circular members fail to be subjected to unequal lateral impact loads provides insight into circular RC members' impact design and damage evaluation.

Significantly Elevated Dielectric and Energy Storage Traits in Boron Nitride Filled Polymer Nano-Composites with Topological Structure

Yefeng Feng,Jianxiong Zhang,Jianbing Hu,Shichun Li,Cheng Peng 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.2

Interface induced polarization has a prominent influence on dielectric properties of 0–3 type polymer based composites containingSi-based semi-conductors. The disadvantages of composites were higher dielectric loss, lower breakdown strength andenergy storage density, although higher permittivity was achieved. In this work, dielectric, conductive, breakdown and energystorage properties of four nano-composites have been researched. Based on the cooperation of fluoropolymer/alpha-SiC layerand fluoropolymer/hexagonal-BN layer, it was confirmed constructing the heterogeneous layer-by-layer composite structurerather than homogeneous mono-layer structure could significantly reduce dielectric loss, promote breakdown strength andincrease energy storage density. The former worked for a larger dielectric response and the latter layer acted as a robust barrierof charge carrier transfer. The best nano-composite could possess a permittivity of 43@100 Hz (~ 3.3 times of polymer),loss of 0.07@100 Hz (~ 37% of polymer), discharged energy density of 2.23 J/cm3@249 kV/cm (~ 10 times of polymer)and discharged energy efficiency of 54%@249 kV/cm (~ 5 times of polymer). This work might enlighten a facile route toachieve the promising high energy storage composite dielectrics by constructing the layer-by-layer topological structure.