• Title/Summary/Keyword: impact behaviour

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Gender Differences in Paediatric Patients of the Swiss Inflammatory Bowel Disease Cohort Study

  • Herzog, Denise;Buehr, Patrick;Koller, Rebekka;Rueger, Vanessa;Heyland, Klaas;Nydegger, Andreas;Spalinger, Johannes;Schibli, Susanne;Braegger, Christian P.;The Swiss IBD Cohort Study Group
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.17 no.3
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    • pp.147-154
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    • 2014
  • Purpose: Gender differences in paediatric patients with inflammatory bowel disease (IBD) are frequently reported as a secondary outcome and the results are divergent. To assess gender differences by analysing data collected within the Swiss IBD cohort study database since 2008, related to children with IBD, using the Montreal classification for a systematic approach. Methods: Data on gender, age, anthropometrics, disease location at diagnosis, disease behaviour, and therapy of 196 patients, 105 with Crohn's disease (CD) and 91 with ulcerative or indeterminate colitis (UC/IC) were retrieved and analysed. Results: The crude gender ratio (male : female) of patients with CD diagnosed at <10 years of age was 2.57, the adjusted ratio was 2.42, and in patients with UC/IC it was 0.68 and 0.64 respectively. The non-adjusted gender ratio of patients diagnosed at ${\geq}10$ years was 1.58 for CD and 0.88 for UC/IC. Boys with UC/IC diagnosed <10 years of age had a longer diagnostic delay, and in girls diagnosed with UC/IC >10 years a more important use of azathioprine was observed. No other gender difference was found after analysis of age, disease location and behaviour at diagnosis, duration of disease, familial occurrence of IBD, prevalence of extra-intestinal manifestations, complications, and requirement for surgery. Conclusion: CD in children <10 years affects predominantly boys with a sex ratio of 2.57; the impact of sex-hormones on the development of CD in pre-pubertal male patients should be investigated.

Analysis Study on Influence that the Center Hole Notch of CFRP with Laminated Structure Affects (적층구조를 가진 CFRP의 중앙 노치구멍이 미치는 영향에 관한 해석적 연구)

  • Park, Jae-Woong;Kim, Eundo;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.9 no.2
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    • pp.177-182
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    • 2018
  • In this paper, the fracture behaviour at CFRP laminated structure due to the vertical falling impact of the fight drone frame composed of CFRP was investigated through the analytical study. As CFRP consists of fiber differently from the existing plastic material, the fracture behaviour becoms complex. So, the preceding study is important through the analytical study before this experiment. By comparing with the existing study model at the same condition as the result of this study, the applied stress value is shown to decrease greatly at the analysis model with the center notch hole of the laminated CFRP drone frame. On the basis of this study result, the esthetic sense can be shown as the foundation data about the notch hole of drone frame are grafted onto the convergence technique.

Assessment of INSPYRE-extended fuel performance codes against the SUPERFACT-1 fast reactor irradiation experiment

  • L. Luzzi;T. Barani;B. Boer;A. Del Nevo;M. Lainet;S. Lemehov;A. Magni;V. Marelle;B. Michel;D. Pizzocri;A. Schubert;P. Van Uffelen;M. Bertolus
    • Nuclear Engineering and Technology
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    • v.55 no.3
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    • pp.884-894
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    • 2023
  • Design and safety assessment of fuel pins for application in innovative Generation IV fast reactors calls for a dedicated nuclear fuel modelling and for the extension of the fuel performance code capabilities to the envisaged materials and irradiation conditions. In the INSPYRE Project, comprehensive and physics-based models for the thermal-mechanical properties of U-Pu mixed-oxide (MOX) fuels and for fission gas behaviour were developed and implemented in the European fuel performance codes GERMINAL, MACROS and TRANSURANUS. As a follow-up to the assessment of the reference code versions ("pre-INSPYRE", NET 53 (2021) 3367-3378), this work presents the integral validation and benchmark of the code versions extended in INSPYRE ("post-INSPYRE") against two pins from the SUPERFACT-1 fast reactor irradiation experiment. The post-INSPYRE simulation results are compared to the available integral and local data from post-irradiation examinations, and benchmarked on the evolution during irradiation of quantities of engineering interest (e.g., fuel central temperature, fission gas release). The comparison with the pre-INSPYRE results is reported to evaluate the impact of the novel models on the predicted pin performance. The outcome represents a step forward towards the description of fuel behaviour in fast reactor irradiation conditions, and allows the identification of the main remaining gaps.

Elastic local buckling behaviour of corroded cold-formed steel columns

  • Nie Biao;Xu Shanhua;Hu WeiCheng;Chen HuaPeng;Li AnBang;Zhang ZongXing
    • Steel and Composite Structures
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    • v.48 no.1
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    • pp.27-41
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    • 2023
  • Under the long-term effect of corrosive environment, many cold-formed steel (CFS) structures have serious corrosion problems. Corrosion leads to the change of surface morphology and the loss of section thickness, which results in the change of instability mode and failure mechanism of CFS structure. This paper mainly investigates the elastic local buckling behavior of corroded CFS columns. The surface morphology scanning test was carried out for eight CFS columns accelerated corrosion by the outdoor periodic spray test. The thin shell finite element (FE) eigen-buckling analysis was also carried out to reveal the influence of corrosion surface characteristics, corrosion depth, corrosion location and corrosion area on the elastic local buckling behaviour of the plates with four simply supported edges. The accuracy of the proposed formulas for calculating the elastic local buckling stress of the corroded plates and columns was assessed through extensive parameter studies. The results indicated that for the plates considering corrosion surface characteristics, the maximum deformation area of local buckling was located at the plates with the minimum average section area. For the plates with localized corrosion, the main buckling shape of the plates changed from one half-wave to two half-wave with the increase in corrosion area length. The elastic local buckling stress decreased gradually with the increase in corrosion area width and length. In addition, the elastic local buckling stress decreased slowly when corrosion area thickness was relatively large, and then tends to accelerate with the reduction in corrosion area thickness. The distance from the corrosion area to the transverse and longitudinal centerline of the plate had little effect on the elastic local buckling stress. Finally, the calculation formula of the elastic local buckling stress of the corroded plates and CFS columns was proposed.

Lagrangian Finite Element Analysis of Water Impact Problem (강체-유체 충격문제에 대한 Lagrangian 유한요소 해석)

  • Bum-Sang Yoon
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.1
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    • pp.60-68
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    • 1991
  • The updated Lagrangian Finite Element Method is introduced to analyse rigid body-fluid impact problem which is characterized by incompressible Navier-Stokes equations and impact-contact conditions between free surface and rigid body. For the convenience of numerical computation, velocity fields are splinted into vicous and pressure parts, and then the governing equations and boundary conditions are decomposed in accordance with the decomposition. However, Viscous stresses acting an the solid boundaries are neglected on the assumption that very small velocity gradients may occur during extremely small time interval of the impact. Four coded quadrilateral elements are used to discretize the space domain and the fully explicit time-marching algorithm is employed with a reasonably small time step. At the beginning of each time step, contact velocity of the rigid body is computed from the momentum balance between the body and the fluid. The velocity field is then computed to satisfy the discretized equations of motions and incompressibility and contact constraints as well as an exact free surface boundary condition. At the end of each time step, the fluid domain is updated from the velocity field. In the present time stepping numerical analysis, behaviour of the free surface near the body can be observed without any difficulty which is very important in the water impact problem. The applicability of the algorithm is illustrated by a wedge type falling body problem. The numerical solutions for time-varying pressure distributions and impact loadings acting ion the surface are obtained.

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Can Managerial Military Experience Affect Corporate Innovation? : Evidence from an Emerging Market

  • Lang, Xiangxiang;You, Dandan;Cui, Li;Peng, Zhe
    • Journal of East Asia Management
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    • v.1 no.1
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    • pp.1-27
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    • 2020
  • Military experience has a great impact on a soldier ability to handle risks. Therefore, when those soldiers become managers, they may behave differently in making risky corporate decisions, especially in activities like the R&D investment. However, studies on how military experience affect R&D have been largely missing in the largest emerging economy, i.e. China, despite that the country hires a higher percentage of military managers than the US. In addition, it remains a question whether military managers affect the state-owned enterprises (SOEs) in China, as many of the corporate decisions are made by the government. This paper tries to address these questions. The imprinting theory and the upper echelon theory suggest that managers' personal experience can affect their behaviour, which in turn influences their corporate decisions. In this paper, we examine whether managers with military experience lead to higher R&D investment and whether such an effect exists in state-owned enterprises. Based on a sample of listed firms in China's A-share market over 2008-2017, we make two findings. First, companies with military managers have high R&D investment. By dividing managers' military positions into high and low rank, we find that companies tend to have higher (lower) R&D investment if their managers hold a high-rank (low-rank) position. Second, the effect of high-rank military managers on R&D investment is more pronounced if the manager is also the founder and the company is a non-state-owned enterprise. For low-ranking military managers, a stronger effect on R&D investment is also observed if they are also the founder, but whether their companies are state-owned or not has no impact on R&D investment. This study identifies managers' military experience as a contributing factors to corporate R&D investment in the largest emerging economy. This paper tests an implication of the imprinting theory and the upper echelon theory, i.e., managers' personal experience can affect their behaviour, which in turn influences their corporate decisions. Specifically, we focus on one aspect of personal experience - military experience - and look at whether it is beneficial to firms' technological innovation, therefore enriches the literature of managerial heterogeneity. Our findings on the influence of managers' military experience on firms' technological innovation can help us better understand the role of managers play in corporate decision making, and how managers' individual traits interact with the firm's characteristics.

The New Structure of Police Governance and Its Impact on Police Service Delivery in the UK (치안 거버넌스의 새로운 구조와 경찰 서비스 제공에 미치는 영향: 영국을 중심으로)

  • Loveday, Barry;Jung, Jeyong
    • Korean Security Journal
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    • no.55
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    • pp.169-192
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    • 2018
  • This article assesses the recent police reform strategy in England and Wales with the Police Reform and Social Responsibility Act 2011. Police and Crime Commissioners have a responsibility not just for the police force but also for reducing crime in their area of responsibility. This ensures that their remit runs much more widely than their predecessor body, the police authority. The article goes on to evaluate the nature and extent of crime by making immediate use of survey of local police commanders. The surveys showed that police commands were swamped with minor crime and anti-social offences. The arrival of Police and Crime Commissioners has meant that now police priorities can be more closely aligned to those of the public and where anti-social behaviour is now recognised as impacting on the lives of many residents more significantly than criminal activity. The article highlights the changes introduced by government following the Winsor Review to police pay, pensions and conditions of service. It reflects on the impact of this on both police morale and professional motivation. It suggests that current government policy is now haemorrhaging the police service as increasing numbers of experienced officers are leaving the police service which could ultimately undermine its long-term resilience as a strategic emergency service.

A Study of Fatigue Crack Growth Behaviour for Ferrite-Bainite Dual Phase Steel (Ferrite-Bainite dual phase 강의 피로균열진전 특성 평가)

  • Kim, Deok-Geun;Cho, Dong-Pil;Oh, Dong-Jin;Kim, Myung-Hyun
    • Journal of Welding and Joining
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    • v.34 no.1
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    • pp.41-46
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    • 2016
  • With the recent increase in size of ships and offshore structures, there are more demand for thicker plates. As the thickness increases, it is known that fatigue life of the structures decrease. To improve the fatigue life, post weld treatments techniques, such as toe grinding, TIG dressing and hammer peening, are typically employed. However, these techniques require additional construction time and production cost. Therefore, it is of crucial interest steels with longer fatigue crack growth life compared to conventional steels. This study investigates fatigue crack growth rate (FCGR) behaviours of conventional EH36 steel and Ferrite-Bainite dual phase EH36 steel (F-B steel). F-B steel is known to have improved fatigue performance associated with the existence of two different phases. Ferrite-Bainite dual phase microstructures are obtained by special thermo mechanical control process (TMCP). FCGR behaviours are investigated by a series of constant stress-controlled FCGR tests. Considering all test conditions (ambient, low temperature, high stress ratio), it is shown that FCGR of F-B steel is slower than that of conventional EH36 steel. From the tensile tests and impact tests, F-B steel exhibits higher values of strength and impact energy leading to slower FCGR.

Study on the Impact Analysis of Front Loader for Tractor (트랙터용 프론트 로더의 충격해석에 관한 연구)

  • Lim, Gi-Soo;Lee, Boo-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.8
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    • pp.5051-5059
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    • 2015
  • Structural behaviour of the front loader for an agricultural tractor was analyzed for three impact test conditions: drop and catch, corner pull, and corner push. Rigid-body dynamic, transient structural, and static structural analyses were conducted using a commercial finite element software. Analysis of the drop and catch test dealt with the case that the bucket located at the maximum elevation was dropped and catched through three steps. Analysis of the corner pull test dealt with the case that the bucket constrained to the ground by a chain at its corner was raised suddenly. Analysis of the corner push test dealt with the case that the corner of the bucket collided with an obstacle. Results of analyses of the three test conditions showed that maximum stress occurs at the geometrically discontinuous location in the mount and is caused from local stress concentration. Results of the present research can be utilized as a guideline to achieve more reliable and safe structural design of the front loaders.

Earthquake-induced pounding between the main buildings of the "Quinto Orazio Flacco" school

  • Fiore, Alessandra;Monaco, Pietro
    • Earthquakes and Structures
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    • v.1 no.4
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    • pp.371-390
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    • 2010
  • Historical buildings in seismically active regions are severely damaged by earthquakes, since they certainly were not designed by the original builders to withstand seismic effects. In particular the reports after major ground motions indicate that earthquake-induced pounding between buildings may lead to substantial damage or even collapse of colliding structures. The research on structural pounding during earthquakes has been recently much advanced, although most of the studies are conducted on simplified single degree of freedom systems. In this paper a detailed pounding-involved response analysis of three adjacent structures is performed, concerning the main bodies of the "Quinto Orazio Flacco" school. The construction includes a main masonry building, with an M-shaped plan, and a reinforced concrete building, separated from the masonry one and realized along its free perimeter. By the analysis of the capacity curves obtained by suitable pushover procedures performed separately for each building, it emerges that masonry and reinforced concrete buildings are vulnerable to earthquake-induced structural pounding in the longitudinal direction. In particular, due to the geometric configuration of the school, a special case of impact between the reinforced concrete structure and two parts of the masonry building occurs. In order to evaluate the pounding-involved response of three adjacent structures, in this paper a numerical procedure is proposed, programmed using MATLAB software. Both a non-linear viscoelastic model to simulate impact and an elastic-perfectly plastic approximation of the storey shear force-drift relation are assumed, differently from many commercial softwares which admit just one non-linearity.