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Entry qualifications and academic performance of architecture students in Nigerian Polytechnics： Are the admission requirements still relevant？

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Frontiers of Architectural Research 2014年第1期3卷 69-75页

作者： Peter 0 Adewale Olasunmbo Bolanle Adhuze Department of Architectural Technology The Federal Polytechnic Ado-Ekiti Ekiti-State Nigeria

The competence of fresh graduates of architecture has been continuously criticized by the industry for inadequate knowledge. This is often blamed on the poor standard of education evidenced by poor performances in professional and degree/diploma examinations conducted by various schools of architecture in the country. Although, factors responsible for the scenario are wetl documented in the literature, most of these works are based on testimonial and circumstantial evidences relating to management of architectural education only. The aim of this paper is to investigate the relationship between entry qualifications and the performance of architecture students in Nigerian Polytechnics with a view to determining the relevance of current admission policy to architectural education in Nigeria. Data were obtained from official records in the Department of Architecture in four randomly selected polytechnics in the southwestern part of Nigeria. Pearson Product Moment Corretation （r） was used to test the hypotheses. Findings reveal weak relationship between the two variables （physics and mathematics）. This is contrary to the expectations of most schotars and policy makers who opine that studentst proficiency in these subjects would enhance their performance at higher LeveLs. The paper traces the contradiction to the poor handling of public examinations and misconception of architecture as being pure science. It holds that if these requirements are still relied upon for the admission of students into schools of architecture, wrong candidates wouldcontinue to gain entry into the profession. The paper concludes by recommending certain measures that are capable of reversing the trend.

关键词： Academic perfor-mance Admission criteria Architecture Arts Education Science

MOTION ERROR ESTIMATION OF 5-AXIS MACHINING CENTER USING DBB METHOD

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 276-281页

作者： CHEN Huawei ZHANG Dawei TIAN Yanling ICHIR0 Hagiwara School of Mechanical Engineering Tianjin UniversityTianjin 300072 China Graduate School of Science and Engineering Tokyo Institute of TechnologyTokyo JAPAN

In order to estimate the motion errors of 5-axis machine center, the double ball bar （DBB） method is adopted to realize the diagnosis procedure. The motion error sources of rotary axes in 5-axis machining center comprise of the alignment error of rotary axes and the angular error due to various factors, e.g. the inclination of rotary axes. From sensitive viewpoints, each motion error is possible to have a particular sensitive direction in which deviation of DBB error trace arises from only some specific error sources. The model of the DBB error trace is established according to the spatial geometry theory. Accordingly, the sensitive direction of each motion error source is made clear through numerical simulation, which is used as the reference patterns for rotational error estimation. The estimation method is proposed to easily estimate the motion error sources of rotary axes in quantitative manner. To verify the proposed DBB method for rotational error estimation, the experimental tests are carried out on a 5-axis machining center M-400 （MORISEIKI）. The effect of the mismatch of the DBB is also studied to guarantee the estimation accuracy. From the experimental data, it is noted that the proposed estimation method for 5-axis machining center is feasible and effective.

关键词： 5-axis NC machine tool Double ball bar(DBB) Motion errors of rotary axes

The Interaction Between The Different Scale Eddies of The Turbulence

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 197-201页

作者： Shida L IU,Fuming L IANG,Shikuo L IU,Guojun XIN (Department of Geophysics,Peking University,Beijng1 0 0 871 ,China) Department of Geophysics Peking University Beijng 100871 China

The turbulence is composed from a large number of eddies of different *** the inertial range,the“2 / 3power-law”for velocity structure function and the“-5 / 3power-law”for energy spectrum were derived by Kolmogorov and were convinced as universal *** this paper,the turbulence which obeys the power-law of the auto-correlation function will be taken as a matter of the different scale Brownian motions which obeys the exponent-law of the auto- correlation function and the local self-similarity for different *** which we demonstrated that the turbulentexchange coefficient of different scale hierarchy changes quantitatively with its scale size and atmospheric stratification stability

关键词： Atmospheric turbulence

Morphological dependence of passive epitaxial oxide films on nanoparticles of iron

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电子显微学报 2002年第5期21卷 601-602页

作者： FUNGKwokKwong ZHANGXi0xiang DepartmentofPhysics TheHongKongUniversityofScienceandTechnologyClearWaterBayKowloonHongKongSARCHina DepartmentofPhysics TheHongKongUniversityofScienceandTechnologyClearWaterBayKowloonHongKongSA

Nanoparticles of iron passivated by thin oxide films are {110} rhombic dodecahedra truncated by {100} planes with various degree of truncation. The degree of truncation is defined as the ratio of the edge length of the truncated part to the full edge length of the rhombic dodecahedron. Uyeda and coworkers have shown that nanoparticles with low degree of truncation are bounded by six small {100} and twelve large {110} facets while nanoparticles with high degree of truncation are bounded by large {100} and small {110} facets.

关键词：电子显微镜组织形貌晶体生长氧化物薄膜铁耐蚀防护

Effects of Haloxylon spp. of Different Age Classes on Vegetation Cover and Soil Properties on an Arid Desert Steppe in Iran

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Pedosphere 2019年第5期29卷 619-631页

作者： Mahdieh EBRAHIMI Fereshteh M0HAMMADI Akbar FAKHIREH Abolfazl BAMERI Department of Range and Watershed Management University of ZabolZabol *** (Iran) Department of Range and Watershed Management University of Gonbad KavosFalahi StreetBasirat BoulevardGonbad Kavos P.O. Box 163 (Iran) Department of Soil Sciences University of ZabolZabol *** (Iran)

In arid regions,afforestation has been considered as a method for ecological revival in terms of vegetation enrichment and soil *** this study,the effects of afforestation with Haloxylon *** vegetation cover and soil properties were measured0-30 and 30-60 cm)under and between shrub *** succession significantly affected plant community *** total,16 species from 8families and 15 genera were observed along the afforestation successional *** species richness and diversity and vegetation cover increased slowly during the succession,and reached the maximum values in the area where Haloxylon had been planted for25 *** nutrient values gradually increased during the succession,and the levels of organic matter,total nitrogen,available potassium,and available phosphorus were significantly higher under Haloxylon canopies than between *** reduced soil pH under and between Haloxylon canopies during the succession,while soil electrical conductivity followed an opposite *** planting increased the silt content in the 0-30 cm soil *** results suggest that Haloxylon establishment plays an important role in the reestablishment of desertified ecosystems in arid regions.

关键词： afforestation succession arid land desertification control plant community soil amelioration species diversity species richness vegetation enrichment

Site 0ccupancy of Alloying Elements and Their Effects on the D0_3 Phase Stability in Fe_3Al

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Journal of Materials Science & Technology 1999年第4期15卷 339-341页

作者： Jun CAF Shaojun LIU Ying LOU and Benkuan usDepartment 0f Physics, Beijing N0rmal University, Beijing lO0875, ChinaSuqing D UANInstitute of Applied Physics and Computati0nal Mathematics, Beijing 100088, China Department of Physics Beijing Normal University Beijing 100875 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

The effects of ternary solutes Ti, Co, V, Cr, Ta, W and Mo on the D03 phase 5tability of Fe3Alintermetallics are investigated by tight-binding linear Muffin-tin orbitaI method. The predictedsite preference5 of these elements in Fe3AI are in agreement with the experimental *** calculated Iocal magnetic moment of Fe3AI is identical to the experimentaI. ln addition, itis found that the D03 phase stability of Fe3AI doped with Ti, V, Co and Cr depends on 'energygap- of energy band near Fermi level. while the D03 phase stability of Fe3AI doped with Ta, Wand Mo may be affected by Madelung energy.

关键词： Al Fe Site 0ccupancy of Alloying Elements and Their Effects on the D03 Phase Stability in Fe3Al

Adaptive Agent-Based Modeling Framework for Collective Decision-Making in Crowd Building Evacuation

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Journal of Shanghai Jiaotong university(Science) 2021年第4期26卷 522-533页

作者： CHEN Feier ZHA0 Qiyuan CA0 Mingming CHEN Jiagi FU Guiguan State Key Laboratory of Ocean Engineering Key Laboratory of Marine Intelligent Equipment and System of Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China Marautec Co. Ltd.Shanghai201206China Zhiyuan College Shanghai Jiao Tong UniversityShanghai200240China School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai200240China Institute of Fintech Shanghai University of Finance and EconomicsShanghai200433China

Crowd evacuation in different situations is an important topic in the research field of safety. This paper presents a hybrid model for heterogeneous pedestrian evacuation simulation. Our adaptive agent-based model (ABM) combines the strength of human crowd behavior description from classical social force models with discrete dynamics expression from cellular automaton models by extending the conception of floor field. Several important factors which may influence the results of decision-making of pedestrians are taken into consideration, such as the location of sign, the attraction of exit, and the interaction among pedestrians. To compare the effect of information on the pedestrians, we construct three decision-making mechanisms with different assumptions. To validate these three simulation models, we compare the numerical results from different perspectives with rational range in the case study where the Tampere Theater evacuation was carried out. The ABM framework is open for rules modification and could be applied to different building plans and has implication for architectural design of gates and signs in order to increase the evacuation efficiency.

关键词： adaptive agent-based model evacuation simulation emergency interaction heterogeneity

Retrofitting of RC Slabs Against Explosive Loads

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Transactions of Tianjin University 2006年第B09期12卷 88-93页

作者： WU Chengqing 0EHLERS Deric John XIA Shaohua School of Civil and Environmental Engineering The University of Adelaide Australia Defence Science and Technological Organization Australia

With the increase of terrorist bomb attacks on buildings, there is a need to develop advanced retrofitting techniques to strengthen structures against blast loads. Currently, several guidelines including an Australian version for retrofitting reinforced concrete (RC) structures are available for the design of retrofitting systems against seismic and monotonic loads using steel or fibre reinforced polymer (FRP) plates that can be either adhesively bonded to the surface or near surface mounted to the concrete cover. However, none of these guidelines provide advice suitable for retrofitting structures subjected to blast loads. In this paper, numerical models are used to simulate the performance of retrofitted RC slabs subjected to blast loads. Airblast pressure distributions on the surface of the slabs estimated in a previous study are used as input in the analysis. A material damage model developed previously for concrete and an elastoplastic model for steel bars are employed in this research for modelling reinforced concrete behaviour due to explosive loads. The material models and blast loading are coded into a finite element computer program LS-DYNA3D to do the analysis. With the numerical model, parametric studies are conducted to investigate RC slabs retrofitted by either externally bonded or near-surface mounted plates or GFRP sheets subjected to blast loads. Discussion is made on the effectiveness of the retrofitting system for RC slabs against blast loads.

关键词： retrofit explosion fibre reinforced polymer slab

MOBILITY EVALUATION AND INNOVATION OF WHEELED SPACE ROVER

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 187-190页

作者： SHANG Jianzhong LU0 Zirong LI Shengyi TANG Li School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074 China School of Mechatronics Engineering and Automation National University of Defense TechnologyChangsha 410073 China

The mission and function requirements of lunar rover are analyzed, based on virtual prototype technology, the mobility evaluation theory and method for wheeled space rover are proposed, which provide a new way to study the innovative design of lunar rover. Based on the above theoretical system, an innovative lunar rover suspension system, which adopts a two-crank-slider mechanism, is proposed, and its dynamics model is created. Adopting virtual prototype technology, the ground adaptability, over-obstacle ability and driving placidity of the rover are evaluated in the virtual prototype software ADAMS. The analysis results show that the rover provides a high degree of mobility.

关键词： Space rover Mobility Virtual prototype Suspension