• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1287-1287
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• 2001

The structure of water molecules in the pure liquid state has been subjected to extensive research for several decades. Questions still remain unanswered, however, and no single model has been found capable of explaining all the anomalies of water. In the present study near-infrared spectra of water in the temperature region 6-$80^{\circ}C$ have been analysed by use of principal component analysis (PCA) and two-dimensional correlation spectroscopy in order to study the dynamic behaviour of the water band centred at 1440 nm, which is due to the combination of symmetric and antisymmetric O-H stretching modes. It has been found that the wavelengths 1412 and 1491 nm account for more than 99% of the spectral variation, representing two major water species with weaker and stronger hydrogen bonds, respectively. A third species located at 1438 nm, whose concentration was relatively constant as a function of temperature, is also indicated. A somewhat distorted two-state structural model for water is suggested.

• Journal of Biomedical Engineering Research
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• v.16 no.1
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• pp.9-16
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• 1995

Biodegradable poly (I ,4-butanediol succinate) (PBS) was synthesized from 1,4-butanediol and succinic anhydride. The glass transition temperature of poly (I, 4-butanediol succinate) was revealed at $73^{\circ}C$. The crystallization and cold crystallization of the polymers were investigated as a function of holding time in melt state, cooling rate. reheating, and molecular weight. Chain scission and/or cmsslinking did not occur in the melt state at var.ious holding times. Slower scanning rate can allow more times for nucleation, rearrangement, and packing of the polymer chain, so the onset temperature of crystallization from the melt was increased. PBS crystallized from the melt was found to have spherulitic structure. The degradation behavior of PBS was studied under basic conditions and with microorganisms using the modified ASTM method. In the basic solution. PBS lost up to 85% of its mass within two days. Based upon visual observation, the crystalline structure of films composed of larger molecular weight polymers retained their crystallinity longer than similar structures in low molecular weight samples.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.4
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• pp.129-137
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• 2016

Transmembrane(TM) proteins are closely related to transport, channel formation, signaling, cell to cell interaction, so they are the crucial target of modern medicinal drugs. In order to study the structure and function of these TM proteins, it is important to prepare reasonable amounts of proteins. However, their preparation is seriously difficult and time-consuming due to insufficient yields and low solubility of TM proteins. We tried to produce large amounts of Syndecan-4 containing TM domain(SDC4-TM) that is related to the wound healing and tumor. Also, mutated SDC4-TM was studied to investigate structural change by modification of dimerization motif. We performed the structure determination by the Polarity Index at Slanted Angle (PISA) wheel pattern analysis based on $^{15}N-^1H$ 2D SAMPI-4 solid-state NMR of SDC4-TM and computational modeling using Discovery Studio 2016.

• Journal of the Korean Chemical Society
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• v.11 no.4
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• pp.143-149
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• 1967

The Transient State Theory of Significant Liquid Structure is applied to a binary liquid solution of benzene and carbon tetrachloride, which gives slightly positive deviation from Raoults law. The partition function for the solution is derived according to the proposed theory. The various thermodynamic properties such as total and partial vapor pressures, molar volumes, entropies of mixing, and compressibilities are calculated at three different temperatures, 298.15^{\circ}K$, 313.15^{\circ}K$ and 343.1515^{\circ}K$. The calculated values agree satisfactorily with experimental data.

• Structural Engineering and Mechanics
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• v.85 no.6
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• pp.729-742
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• 2023

It is a recent attraction to the mechanical scientists to investigate state of wave propagation, buckling and vibration in the sport balls to observe the importance of different parameters on the performance of the players and the quality of game. Therefore, in the present study, we aim to investigate the wave propagation in handball game ball in term of mass of the ball and geometrical parameters wit incorporation of the viscoelastic effects of the ball material into account. In this regard, the ball is modeled using thick shell structure and classical elasticity models is utilized to obtain the equation of motion via Hamilton's principle. The displacement field of the ball model is obtained using first order shear deformation theory. The resultant equations are solved with the aid of generalized differential quadrature method. The results show that mass of the ball and viscoelastic coefficient have considerable influence on the state of wave propagation in the ball shell structure.

• Structural Engineering and Mechanics
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• v.92 no.2
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• pp.207-226
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• 2024

Recently, the phenomenon of disproportionate structural failure caused by blast load has grown more common in the field of engineering design. Blast-resistant analyses and designs have been developed by many structural techniques and methodologies to forecast the loads produced by a high explosive charge on structures with complicated geometry. These techniques are based on a good understanding of blast phenomena to analyze structures exposed to blast load. This paper provides a current state-of-the-art review of blast prediction and simulation methods to predict the design blast loads that are used to assess the structural response and damage level to an existing or new building. The damage criteria from the general design approach relevant to civil design applications in forecasting blast loads as well as structural system responses will be provided. Identifying the structures' expected damage class would aid in providing extra reinforcing or strengthening for damaged elements to meet the acceptance criteria or minimize damage by a suitable blast mitigation strategy. Based on identifying the damage class expected of a structure subjected to an explosion, blast mitigation strategies could be used to minimize damage and maximize the ability of the structure to function even after the explosion.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.5199-5205
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• 2013

Despite the increasing incidence of earthquakes in recent years, many of the existing buildings don't have appropriate seismic performance due to the deterioration or structural characteristics. In particular, a piloti-type RC shear wall structure, which is one of the building types in Korea, is highly vulnerable to earthquakes due to a great lack of shear function that can resist lateral force caused by the earthquake since the first floor is mostly soft story, and it is classified as weak story. In this regard, a study on the damage state criterion for the piloti-type RC shear wall structures was carried out. The capacity spectrum was calculated through the structural analysis by selecting typical type of buildings of shear wall systems, and damage state criterion was defined based on the shape of the capacity spectrum.

• Structural Engineering and Mechanics
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• v.37 no.6
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• pp.671-684
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• 2011

Deciding on an optimal sensor placement (OSP) is a common problem encountered in many engineering applications and is also a critical issue in the construction and implementation of an effective structural health monitoring (SHM) system. The present study focuses with techniques for selecting optimal sensor locations in a sensor network designed to monitor the health condition of Dalian World Trade Building which is the tallest in the northeast of China. Since the number of degree-of-freedom (DOF) of the building structure is too large, multi-modes should be selected to describe the dynamic behavior of a structural system with sufficient accuracy to allow its health state to be determined effectively. However, it's difficult to accurately distinguish the translational and rotational modes for the flexible structures with closely spaced modes by the modal participation mass ratios. In this paper, a new method of the OSP that computing the mode shape matrix in the weak axis of structure by the simplified multi-DOF system was presented based on the equivalent rigidity parameter identification method. The initial sensor assignment was obtained by the QR-factorization of the structural mode shape matrix. Taking the maximum off-diagonal element of the modal assurance criterion (MAC) matrix as a target function, one more sensor was added each time until the maximum off-diagonal element of the MAC reaches the threshold. Considering the economic factors, the final plan of sensor placement was determined. The numerical example demonstrated the feasibility and effectiveness of the proposed scheme.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.86-89
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• 1995

In this pacer, The effect of the impedances in SNOSEFT s memory devices has been developed. The effect of source and drain impedances are measuring using the method of the field effect bias resistance in the inner resistance regions of the device structure and external bias resistance. The effect of impedance by source and drain resistance shows according to increasing to the storage of memory charges, shows according to a function of decreasing to the gate voltages, shows the delay of threshold voltages, The delay time of low conductance state and high conductance state by the impedance effect shows 3 [${\mu}$sec] and 1[${\mu}$sec] respectively.

• Genomics & Informatics
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• v.12 no.3
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• pp.105-113
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• 2014

A subset of mammalian genes differ functionally between two alleles due to genomic imprinting, and seven such genes (Peg3, Usp29, APeg3, Zfp264, Zim1, Zim2, Zim3) are localized within the 500-kb genomic interval of the human and mouse genomes, constituting the Peg3 imprinted domain. This Peg3 domain shares several features with the other imprinted domains, including an evolutionarily conserved domain structure, along with transcriptional co-regulation through shared cis regulatory elements, as well as functional roles in controlling fetal growth rates and maternal-caring behaviors. The Peg3 domain also displays some unique features, including YY1-mediated regulation of transcription and imprinting; conversion and adaptation of several protein-coding members as ncRNA genes during evolution; and its close connection to human cancers through the potential tumor suppressor functions of Peg3 and Usp29. In this review, we summarize and discuss these features of the Peg3 domain.