Behaviour of unbonded reinforcement bar anchored in grouted spiral under increasing flexural bending

This project report presents a research on the behaviour of beam with unbonded reinforcement bars being anchored into grouted spiral reinforcement at both ends and subjected to flexural loading. The use of spiral reinforcement is rather a new concept used in construction industry and still being studied on its application. Spiral reinforcement is believed to improve the bonding between concrete and steel, and currently being used in precast concrete connection. A series of laboratory testing was carried out to obtain required values which demonstrate the behaviour of beam anchored with spiral reinforcement. Total of six concrete beam specimens containing grouted spiral reinforcement were constructed and tested for flexural capacity, deflection and bond-slip of reinforcement. The parameters included in study were different inner diameter (33mm and 58mm) and pitch distance (15mm and 30mm) of spiral reinforcement. By using simple statistically and graphical method, analysis was carried out to determine the effectiveness of end anchorage in providing full flexural resistance to the concrete beam. The results were analysed for bond stress around the reinforcement bar under the effect of spiral confinement. Comparisons of results are carried to determine the influence of inner diameter and pitch distance of spiral reinforcement to the flexural capacity of concrete beam. From the test and analysis, it is found that even with unbonded reinforcement, the grouted spiral reinforcement at beam ends were able to provide full tension support to concrete beam in resisting flexural loading. Despite the unbonded section of reinforcement, the concrete beam able to sustain higher flexural load, estimate 23% more than typical concrete beam. The test also showed that increment in inner diameter or pitch distance of spiral reinforcement will reduce the bond strength between grout and reinforcement bar and subsequently reduced the flexural capacity of the concrete beam

Wat bezielt ons?

In de hedendaagse wetenschap heeft de vertrouwde tegenstelling tussen geest en lichaam plaats gemaakt voor een nieuwe tweedeling: die tussen ons redenerende, rationele, afstandelijke en trage denkende zelf en het gepassioneerde, bevooroordeelde, snelle en efficiënte reagerende zelf1. Dit laatste noemt men ook “het adaptief onbewuste” (Wilson 2002, Fine 2006) of, in eigen land, “het slimme onbewuste” (Dijksterhuis 2007). Het paradigma van het adaptief onbewuste bundelt een grote diversiteit van ontwikkelingen in de cognitieve, gedrags en neurowetenschappen. Wat deze ontwikkelingen met elkaar gemeen hebben is de visie dat onbewuste processen ons gedrag en handelen (én denken) verregaand beïnvloeden. ‘Onbewuste processen’ wil hier zeggen: processen die zich buiten onze aandacht voltrekken en waar wij derhalve niet direct verslag van kunnen doen en/of feitelijk verslag van doen, wanneer ons gevraagd wordt naar de redenen voor onze gedragingen en handelen

Responsibility, Determinism and Freedom

This book shows why we can justify blaming people for their wrong actions even if free will turns out not to exist. Contrary to most contemporary thinking, we do this by focusing on the ordinary everyday wrongs each of us commits, not on the extra-ordinary, "moral monster"-like crimes and weak-willed actions of some. This enables us to justify our everyday practices without the need to deny that free will might be relevant to considerations about personal desert.Value inquiry book series, ISSN 0929-8436 ; vol. 166. Studies in applied ethic

Justifying Blame: why free will matters and why it does not

This book shows why we can justify blaming people for their wrong actions even if free will turns out not to exist. Contrary to most contemporary philosophizing about this issue, we do this not by denying that free will is relevant to considerations about personal desert. Instead we reconsider the preconditions of our ascriptions of responsibility to one another, before discussing the metaphysical consequences of its conditions. We argue that the kind of actions we generally blame one another for are quite ordinary wrong ones: actions we consider to be impolite, insensitive, anti-social, and so on. This blame, we argue, we can justify irrespective of whether we believe that free will exists. We should not make the mistake though, to extend this justification of our blame, to wrong actions that are much more difficult to understand, for example, "moral monster"-like ones.This book shows why we can justify blaming people for their wrong actions even if free will turns out not to exist. Contrary to most contemporary thinking, we do this by focusing on the ordinary, everyday wrongs each of us commits, not on the extra-ordinary, "morally monstrous-like" crimes and weak-willed actions of some

The origin of exciton mass in a frustrated Mott insulator Na2_2IrO3_3

We use a three-pulse ultrafast optical spectroscopy to study the relaxation processes in a frustrated Mott insulator Na$_2$IrO$_3$. By being able to independently produce the out-of-equilibrium bound states (excitons) of doublons and holons with the first pulse and suppress the underlying antiferromagnetic order with the second one, we were able to elucidate the relaxation mechanism of quasiparticles in this system. By observing the difference in the exciton dynamics in the magnetically ordered and disordered phases we found that the mass of this quasiparticle is mostly determined by its interaction with the surrounding spins

Forecasting performance of Logistic STAR exchange rate model: The original and reparameterised versions

Exponential Smooth Transition Autoregressive (ESTAR) model is widely adopted in the exchange rate study as its symmetrical distribution matches that of the symmetrical exchange rate adjustment behaviour. In contrast, another specification of STAR model, namely the LSTAR (logistic STAR) model is discarded by most researchers in priori in their exchange rate modeling exercises due to its undesired property of being asymmetry. This study is the first of its kind in examining the validity of this hypothesis that the ESTAR exchange rate model is superior to LSTAR exchange rate model on the basis of forecasting accuracy. Based on the experience of the adjustment process of two nominal exchange rates, we find that the hypothesis is merely theoretical since we fail to provide consistent empirical evidence in favour of the null hypothesis. This warrants us that we need not be too pessimistic on the usage of LSTAR model in exchange rate study. In our effort to rekindle the usage of LSTAR model, we further reparameterized the original version into the so-called absolute version, which has symmetrical distribution properties, in accordance with the well-known symmetrical adjustment process of exchange rate. The resulting ALSTAR model has proven to be a more promising model in the sense that it has improved significantly from its original version as well as the ESTAR model, which has thus far been deemed the most appropriate nonlinear exchange rate model.LSTAR; ESTAR; forecasting accuracy; nonlinear; exchange rate

Valley-selective optical Stark effect in monolayer WS2

Breaking space-time symmetries in two-dimensional crystals (2D) can dramatically influence their macroscopic electronic properties. Monolayer transition-metal dichalcogenides (TMDs) are prime examples where the intrinsically broken crystal inversion symmetry permits the generation of valley-selective electron populations, even though the two valleys are energetically degenerate, locked by time-reversal symmetry. Lifting the valley degeneracy in these materials is of great interest because it would allow for valley-specific band engineering and offer additional control in valleytronic applications. While applying a magnetic field should in principle accomplish this task, experiments to date have observed no valley-selective energy level shifts in fields accessible in the laboratory. Here we show the first direct evidence of lifted valley degeneracy in the monolayer TMD WS2. By applying intense circularly polarized light, which breaks time-reversal symmetry, we demonstrate that the exciton level in each valley can be selectively tuned by as much as 18 meV via the optical Stark effect. These results offer a novel way to control valley degree of freedom, and may provide a means to realize new valley-selective Floquet topological phases in 2D TMDs

Hoezo vrije wil?

Bestaat de vrije wil? Stel die vraag aan een filosoof en het antwoord is een wedervraag: Wat bedoel je precies met ‘de vrije wil’? Dit boek legt uit waarom die wedervraag wordt gesteld. Zo’n uitleg is hoognodig, want er gaat nauwelijks een dag voorbij zonder dat wetenschappers claimen te hebben aangetoond dat ‘de vrije wil niet bestaat’, omdat ‘ons brein voor ons beslist’ of ‘aanwijsbare oorzaken in onze omgeving ons doen en laten bepalen’. Filosofen fungeren in deze berichtgeving vaak als de laatsten die geloven in een cartesiaans ego dat zich onttrekt aan materie en oorzakelijkheid -- alsof er sinds Descartes in de filosofie geen woord meer vuil is gemaakt aan het onderwerp. Helemaal verwonderlijk is dit niet. De hedendaagse filosofische discussie over de onderwerpen die schuilgaan onder de noemer ‘de vrije wil’ is vaak gedetailleerd, technisch en lastig te volgen. Bovendien is er in die bijdragen vaak weinig aandacht voor het wetenschappelijke onderzoek zelf dat zoveel publieke aandacht voor de vrije wil losmaakt, en ook niet voor de praktische implicaties van de abstracte filosofische argumenten

Pembangunan portal pendidikan teknik dan vokasional: satu kajian awal di kalangan Pelajar Sarjana PTV Jabatan Pendidikan Teknik dan Vokasional Fakulti Teknologi Kejuruteraan

Tujuan kajian ini adalah untuk mengkaji sejauh manakah keperJuan pelajar terhadap portal Pendidikan Teknik dan Vokasional (PTV). Sebuah portal PTV dibangunkan dalam kajian berasaskan produk ini. Sampel bagi kajian ini terdiri daripada pelajar sarjana pendidikan teknik dan vokasional, semester 3. Dapatan kajian ini dianalisis dengan menggunakan perisian SPSS versi 10. Pada peringkat awal projek ini, keperluan pelajar terhadap portal PTV dikenal pasti. Selepas itu, ciri-ciri yang perlu dibangunkan dalam portal PTV dikenal pasti dengan menggunakan kaedah borang soal selidik. Satu portal PTV dibangunkan berdasarkan dapatan kajian tersebut. Pada peringkat akhir projek ini, penilaian dilakukan ke atas portal PTV yang telah dibangunkan. Tujuan penilaian ini adalah untuk mengenal pasti sejauh manakah portal PTV ini memenuhi keperluan pelajar. Daripada dapatan kajian didapati portal PTV amat diperlukan oleh pelajar. Selain daripada itu, daripada dapatan kajian, portal PTV yang telah dibangunkan ini beryaya memenuhi keperluan pelajar. Cadangan untuk memperbaiki portal PTV yang telah dibangunkan ini diberi oleh responden. Kajian lanjutan patut dilakukan ke atas portal PTV yang telah dibangunkan bagi memperbaiki serta memumikan konsep reka bentuk dan pengurusan maklumat