• Journal of Korean Library and Information Science Society
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• v.37 no.1
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• pp.283-303
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• 2006

An understanding the information seeking-behaviour of archival users is a basic for archival reference services. This study tries to understand who are users of internet board of archives, how and why they ask questions. And the study examines how archivists answer the users' questions. The data used in this study are 3,760 answers and questions in the internet board of National Archives and Record Service during $2000\sim2005$. According to this analysis. lots of users of the board make queries for archival management and asking various archives. And they are public officials, archivists, students, researches, and producers of media. The users mainly ask simple questions and it take average 5 days for users to get answers.

• Wind and Structures
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• v.6 no.6
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• pp.451-470
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• 2003

The classical two-degree-of-freedom (2-d-o-f) "sectional model" is of common use to study the dynamics of suspension bridges. It takes into account the first pair of vertical and torsional modes of the bridge and describes well global oscillations caused by wind actions on the deck, yielding very useful information on the overall behaviour and the aerodynamic and aeroelastic response; however, it does not consider relative oscillations between main cables and deck. On the contrary, the 4-d-o-f model described in the two Parts of this paper includes longitudinal deformability of the hangers (assumed linear elastic in tension and unable to react in compression) and thus allows to take into account not only global oscillations, but also relative oscillations between main cables and deck. In particular, when the hangers go slack, large nonlinear oscillations are possible; if the hangers remain taut, the oscillations remain small and essentially linear: the latter behaviour has been the specific object of Part I (Sepe and Augusti 2001), while the present Part II investigates the nonlinear behaviour (coexisting large and/or small amplitude oscillations) under harmonic actions on the cables and/or on the deck, such as might be generated by vortex shedding. Because of the discontinuities and strong nonlinearity of the governing equations, the response has been investigated numerically. The results obtained for sample values of mechanical and forcing parameters seems to confirm that relative oscillations cannot a priori be excluded for very long span bridges under wind-induced loads, and they can stimulate a discussion on the actual possibility of such phenomena.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.718-724
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• 2006

The heterogeneous association behaviour of various concentration binary mixtures of mono alkyl ethers of ethylene glycol with ethyl alcohol were investigated by dielectric measurement in benzene solutions over the entire concentration range at 25 ${^{\circ}C}$. The values of static dielectric constant $\epsilon_0$ of the mixtures were measured at 1 MHz using a four terminal dielectric liquid test fixture and precision LCR meter. The high frequency limiting dielectric constant $\epsilon_\infty$ values were determined by measurement of refractive index $n_D$ ($\epsilon_\infty\;=\;n_D\;^2$). The measured values of $\epsilon_0$ and $\epsilon_\infty$ were used to evaluate the values of excess dielectric constant $\epsilon^E$, effective Kirkwood correlation factor $g^{eff}$ and corrective correlation factor $g_f$ of the binary polar mixtures to obtain qualitative and quantitative information about the H-bond complex formation. The non-linear behaviour of the observed $\epsilon_0$ values of the polar molecules and their mixtures in benzene solvent confirms the variation in the associated structures with change in polar mixture constituents concentration and also by dilution in non-polar solvents. Appearance of the maximum in $\epsilon^E$ values at different concentration of the polar mixtures suggest the formation of stable adduct complex, which depends on the molecular size of the mono alkyl ethers of ethylene glycol. Further, the observed $\epsilon^E$ < 0 also confirms the heterogeneous H-bond complex formation reduces the effective number of dipoles in these polar binary mixtures. In benzene solutions these polar molecules shows the maximum reduce in effective number of dipoles at 50 percent dilutions. But ethyl alcohol rich binary polar mixtures in benzene solvent show the maximum reduce in effective number of dipoles in benzene rich solutions.

• Journal of Educational Research in Mathematics
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• v.16 no.1
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• pp.43-58
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• 2006

An objective of this paper is to discuss the didactical contracts which have been conceptualized by Brousseau. He modelled mathematics instruction as a game. In such game, didactical contracts existed as its own hidden rules which teacher and student should obey Brousseau introduced it to reveal certain hidden rules which regulates mathematics instruction. Those rules are implicit and reciprocal. In particular, it is not revealed until students break. He defined didactical contracts as teacher's behaviour and corresponding students 'behaviour in order to define it operationally. He he did not define it in psychological and epistemological dimension. But it is necessary to discuss teacher's belief system and epistemology, since teacher's behaviour in instruction is affected by them. He also did not discuss fully teacher's breaking of didactical contracts.

• Korean Journal of Health Education and Promotion
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• v.16 no.1
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• pp.167-185
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• 1999

The purpose of this study was to analyze the content of the sexual knowledge and sexual attitude of the results of 39 previous studies for the adolescence in Korea, 1976-1997. The basis for analysis was the Guidelines for Comprehensive Sexuality Education developed by the Sex Information and Education Council of the U. S.(SIECUS). SIECUS is consisted of six key concepts; Human development, Relationships, Personal skills, Sexual behaviour, Sexual health, Society and Health. The research consisted of 39 articles that met definitional criteria of content analysis. The results of the study were summarized as follows: 1. Knowledge: It was conducted 96.7% of human development, 90.0% of sexual health, 70.0% of sexual behaviour, 23.3% of society and culture. 2. Attitude: It was conducted 94.1% of sexual behaviour, 73.5% of relationships, 55.9% of sexual health, 41.1% of human development, 26.5% of society and culture, 11.8% of personal skills. 3. General characteristics: With regard to sexual knowledge, 50.0% of research were published 1980s, 43.3% were 1990s, and 6.7%were 1970s. As regard to sexual attitude, 50% of research were published 1980s, 45.5% were 1990s, and 2.9% were 1970s. In sample size, 23.1% of 600 over, 401-500 were 20.5%. In the research tool, it was developed by researcher mainly 66.7%, modified tool by researcher was 5.1%. The tested reliability of the research tool was only 27.9%. And 78.9% of the research was not tested in validity of tool.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1997.10a
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• pp.7-7
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• 1997

During sintering of very porous green bodies, as obtained by compaction of hard powders - such as tungsten carbide or ceramics - or by injection moulding, important shrinkage occurs. Due to heterogeneous green density field, gravity effects, friction on the support, thermal gradients, etc., this shrinkage is often non-uniform, which' may induce significant shape changes. As the ratio of compact dimension to powder size is very high, the mechanics of continuum is relevant to model such phenomena. Thus numerical techniques, such as the finite element method can be used to simulate the sintering process and predict the final shape of the sintered part. Such type of simulation has much been developed in the last decade firstly for hot isostatic pressing and next for die compaction. Finite element modelling has been recently applied to free sintering. The simulation of sintering should be based on constitutive equations describing the thermo-mechanical behaviour of the material under any state of stress and any temperature which may arise within the sintering body. These equations can be drawn either from experimental data or from micromechanical models. The experiments usually consist in free sintering and sinter-forging tests. Indeed applying more complex loading conditions at high temperature under controlled atmosphere is delicate. Micromechanical models describe the constitutive behaviour of aggregates of spheres from the deformation of two-sphere contact either by viscous flow or grain boundary diffusion. Such models are not able to describe complex microstructure and mechanisms as observed in real materials but they can give some basic information on the formulation of constitutive equations. Practically both experimental and theoretical approaches can be coupled to identify the constitutive equations. Such procedure has been performed for modelling the sintering of compacts obtained by die pressing of a mixture of tungsten carbide and cobalt powders. The constitutive behaviour of this material during sintering has been described by a linear viscous constitutive model, whose functions have been fitted from results of free sintering and sinter-forging experiments. This model has next been introduced in ABAQUS finite element code to simulate the sintering of heterogeneous green compacts of various geometries at constant temperature. Examples of simulations are shown and compared with experiments.

• Tunnel and Underground Space
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• v.23 no.4
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• pp.280-287
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• 2013

Finite element or difference methods are applied to the analysis of the tunnel stability and they provide detailed behaviour of analyzed tunnel sections but it is rather inefficient to analyze all the section of tunnel by using these methods. In this study, the authors suggest a new stability analysis method for whole tunnel to provide an efficient and easy way to understand the behaviour of whole tunnel by using an analytical solution with the assumption of equivalent circular tunnel. The mechanical behaviour, radial strain and plastic zone radius of whole tunnel were analyzed and appropriate support pressure to maintain the displacement within the allowable limit was suggested after the application of this method to the tunnel. Consequently, it was confirmed that this method can provide quick analysis of the whole tunnel stability and the quantitative information for subsequent measures such as selection of tunnel sections for detailed numerical analysis, set up of the monitoring plan, and so on.

• CELLMED
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• v.2 no.4
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• pp.36.1-36.4
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• 2012

This study was carried out to investigate the neurobehavioural effects of the smoking of Carica papaya leaves based on ethnopharmacological information. Twenty -four rats used for the study were grouped into four groups namely; Groups 1 (Control, unexposed to any smoke) and Groups 2 - 4 (exposed to smoke from varying amount of pawpaw leaf powder). Groups 2, 3, and 4 were exposed to smoke from 6.25 g (low dose), 12.50 g (medium dose), and 18.75 g (high dose) of dry pawpaw leaves respectively in a smoking chamber twice daily for 21 one days with each exposure lasting 3 min. The spontaneous motor activities and locomotory behaviour of the animals were assessed using an open field maze and hole board maze test. The results showed that the smoking of Carica papaya leaves led to a significant (p < 0.05) increase in locomotory activities from $33.36{\pm}3.36$ (control) to $66.50{\pm}6.16$ (high dose), number of head dips (from $8.50{\pm}0.36$, to $12.83{\pm}0.87$) and rearing behaviour (from $14.83{\pm}0.74$, to $27.0{\pm}1.46$). However, the freezing durations as animals were introduced into the maze and grooming behaviour were significantly (p < 0.05) reduced in the treated groups. In conclusion, the increased ambulations and exploratory behaviours imply that the anxiety level is low in the treated groups compared to the control group which thus confirms that dry Carica papaya leaf may possibly contain psychoactive substance(s) that become active when smoked.

• Structural Engineering and Mechanics
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• v.39 no.1
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• pp.125-145
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• 2011

Pushover analysis has gained significant popularity as an analytical tool for realistic determination of the inelastic behaviour of RC structures. Though significant work has been done to evaluate the demands realistically, the evaluation of capacity and realistic failure modes has taken a back seat. In order to throw light on the inelastic behaviour and capacity evaluation for the RC framed structures, a 3D Reinforced concrete frame structure was tested under monotonically increasing lateral pushover loads, in a parabolic pattern, till failure. The structure consisted of three storeys and had 2 bays along the two orthogonal directions. The structure was gradually pushed in small increments of load and the corresponding displacements were monitored continuously, leading to a pushover curve for the structure as a result of the test along with other relevant information such as strains on reinforcement bars at critical locations, failure modes etc. The major failure modes were observed as flexural failure of beams and columns, torsional failure of transverse beams and joint shear failure. The analysis of the structure was by considering all these failure modes. In order to have a comparison, the analysis was performed as three different cases. In one case, only the flexural hinges were modelled for critical locations in beams and columns; in second the torsional hinges for transverse beams were included in the analysis and in the third case, joint shear hinges were also included in the analysis. It is shown that modelling and capturing all the failure modes is practically possible and such an analysis can provide the realistic insight into the behaviour of the structure.

• Steel and Composite Structures
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• v.32 no.1
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• pp.1-19
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• 2019

The aim of the paper is the prediction of the seismic collapse mode of steel storage pallet racks under seismic loads. The attention paid by the researchers on the behaviour of the industrial steel storage pallets racks is increased over the years thanks to their high dead-to-live load ratio. In fact, these structures, generally made by cold-formed thin-walled profiles, present very low structural costs but can support large and expensive loads. The paper presents a prediction of the seismic collapse modes of multi-storey racks. The analysis of the possible collapse modes has been made by an approach based on the kinematic theorem of plastic collapse extended to the second order effects by means of the concept of collapse mechanism equilibrium curve. In this way, the dissipative behaviour of racks is determined with a simpler method than the pushover analysis. Parametric analyses have been performed on 24 racks, differing for the geometric layout and cross-section of the components, designed in according to the EN16618 and EN15512 requirements. The obtained results have highlighted that, in all the considered cases, the global collapse mechanism, that is the safest one, never develops, leading to a dangerous situation that must be avoided to preserve the structure during a seismic event. Although the studied racks follow all the codes prescriptions, the development of a dissipative collapse mechanism is not achieved. In addition, also the variability of load distribution has been considered, reflecting the different pallet positions assumed during the in-service life of the racks, to point out its influence on the collapse mechanism. The information carried out from the paper can be very useful for designers and manufacturers because it allows to better understand the racks behaviour in seismic load condition.