• IMMUNE NETWORK
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• v.4 no.1
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• pp.7-15
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• 2004

Background: The heat shock proteins (HSPs) play an important role in cellular protection mechanisms against physical or chemical stresses. In this study scFv antibodies specific for human HSP70.1 were isolated from a semi-synthetic human scFv library with the ultimate goal of developing anti-HSP70.1 intracellular antibody (intrabody) that may offer an attractive alternative to gene targeting to study the function of the protein in cells. Methods: A semi-synthetic human scFv display library ($5{\times}10^{8}$ size) was constructed using pCANTAB-5E vector and the selection of the library against bacterially expressed recombinant human HSP70.1 was attempted by panning. Results: Three positive clones specific for recombinant HSP70.1 were identified. All three clones used $V_{H}$ subgroup III. On the other hand, $V_{L}$ of two clones belonged to the kappa light chain subgroup I, but the other utilized $V_{k}$ subgroup IV Interestingly, these scFv molecules specifically reacted to the recombinant HSP70.1, yet failed to recognize native HSP70 induced in U937 human monocytic cells by heat treatment. Conclusion: Our results indicated that affinity selection of an scFv phage display library using recombinant antigens produced in E. coli might not guarantee the isolation of scFv antibody molecules specific for a native form of the antigen. Therefore, the source of target antigens needs to be chosen carefully in order to isolate biofunctional antibody molecules.

• Structural Engineering and Mechanics
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• v.30 no.6
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• pp.713-732
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• 2008

Serviceability and durability of the concrete members can be seriously affected by the corrosion of steel rebar. Carbonation front and or chloride ingress can destroy the passive film on rebar and may set the corrosion (oxidation process). Depending on the level of oxidation (expansive corrosion products/rust) damage to the cover concrete takes place in the form of expansion, cracking and spalling or delamination. This makes the concrete unable to develop forces through bond and also become unprotected against further degradation from corrosion; and thus marks the end of service life for corrosion-affected structures. This paper presents an analytical model that predicts the weight loss of steel rebar and the corresponding time from onset of corrosion for the known corrosion rate and thus can be used for the determination of time to cover cracking in corrosion affected RC member. This model uses fully the thick-walled cylinder approach. The gradual crack propagation in radial directions (from inside) is considered when the circumferential tensile stresses at the inner surface of intact concrete have reached the tensile strength of concrete. The analysis is done separately with and without considering the stiffness of reinforcing steel and rust combine along with the assumption of zero residual strength of cracked concrete. The model accounts for the time required for corrosion products to fill a porous zone before they start inducing expansive pressure on the concrete surrounding the steel rebar. The capability of the model to produce the experimental trends is demonstrated by comparing the model's predictions with the results of experimental data published in the literature. The effect of considering the corroded reinforcing steel bar stiffness is demonstrated. A sensitivity analysis has also been carried out to show the influence of the various parameters. It has been found that material properties and their inter-relations significantly influence weight loss of rebar. Time to cover cracking from onset of corrosion for the same weight loss is influenced by corrosion rate and state of oxidation of corrosion product formed. Time to cover cracking from onset of corrosion is useful in making certain decisions pertaining to inspection, repair, rehabilitation, replacement and demolition of RC member/structure in corrosive environment.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.477-486
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• 2017

This review provides an overview of dietary nucleotides as an alternative to in-feed antibiotics for weaning pigs. Dietary nucleotides are composed of DNA or RNA molecules and are normally contained in protein-rich feed ingredient, brewer's yeast, yeast extract, and milk. Weaning pigs are suffering from several stresses, such as environmental challenges (i.e. crowding, transportation, and feeding). Such stressors can damage the intestinal epithelium and cause an invasion by Escherichia coli, secondary inflammatory responses, and post weaning diarrhea. To overcome weaning disorder, people often use antibiotics which reduce symptoms and boost growth performance. However, since antibiotics were banned due to concerns of antibiotic resistant bacteria, researchers are studying alternative materials to antibiotics. Dietary nucleotides are one of the alternative materials for replacing antibiotics and can be used in abnormal conditions, such as weaning diarrhea, low digestibility, and disease condition. Nucleotides have substances that have important roles in cell division and cell growth, affecting growth performance, intestinal condition, and immunological effect at the weaning stage. However, nucleotides' composition is very different between sources and this aspect makes it difficult to utilize nucleotides at the weaning stage. Therefore, this review paper focuses on i) the characteristics and functions of dietary nucleotides and ii) the effect of dietary nucleotides on the growth performance and immune system of pigs.

• The Journal of Advanced Prosthodontics
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• v.7 no.3
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• pp.240-248
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• 2015

PURPOSE. To explore whether there is matching relation between the length and the tilting angle of terminal implants in the All-on-Four protocol by studying the effects of different implant configurations on stress distributions of implant, bone, and framework. MATERIALS AND METHODS. Four implants were employed to support a full-arch fixed prosthesis and five three-dimensional finite element models were established with CT images, based on the length (S and L) and distal tilt angle ($0^{\circ}$, $30^{\circ}$ and $45^{\circ}$) of terminal implants for an edentulous mandible, which named: Tilt0-S, Tilt30-S, Tilt30-L, Tilt45-S and Tilt45-L. An oblique 240 N was loaded at second molar. The von Mises Stresses were analyzed. The implants were consecutively named #1 to #4 from the loading point. RESULTS. 1) Tilt0-S had the greatest stress on the implants, with the other groups exhibiting variable reductions; the four implants of Tilt45-L demonstrated the greatest reduction in stress. 2) Tilt0-S had the greatest stress at bone around #1 implant neck, and Tilt45-L exhibited the least stress, which was a 36.3% reduction compared to Tilt0-S. 3) The greatest stress in the framework was found on the cantilevers distal to #1 implant. Tilt45-S exhibited the least stress. CONCLUSION. Matching different length and tilting angle of the terminal implants led to variable stress reductions on implants, bone and the superstructure. By optimizing implant configuration, the reduction of stress on implants and surrounding bone could be maximized. Under the present condition, Tilt45-L was the preferred configuration. Further clinical testings are required.

• Korean Journal of Social Welfare
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• v.62 no.2
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• pp.29-55
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• 2010

The purpose of this study is to understand how Vietnamese migrated women's family members understand cultural differences and to review the causes and types of family conflict during the acculturation. To do this, the researcher interviewed 10 cases which consist of three family members in a case: a Vietnamese migrated woman, her husband and mother in law. Research results are as follows. First, they are three main factors such as different ways to communicate, patriarchic ways of thinking and different ways of daily life which have caused family conflict. The conflict caused has been reinforced by anger and frustration against other family members. However, based on understanding on the preciousness of family and importance of inter-respect, it is still on going to find out the moderate way to manage family conflict among their family members. This study has practical and methodological significances. At policy and practice level, this research stresses on the significance of focusing on the family as a unit to be approached for policy and practice intervention. As the methodological aspect, the research tried to search the relationship among family members in the Vietnamese migrated women's family by including not only a migrated woman but also her husband and mother in law. However, there is a limit as it only focuses on cases which family members could manage the family conflict.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.6
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• pp.117-125
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• 1998

The paper attempts to estimate the incubation time of a cavity in the interface between a power law creep particle and an elastic matrix subjected to a uniaxial stress. Since the power law creep particle is time dependent, the stresses in the interface relax. The volume free energy associated with Helmholtz free energy includes strain energies caused by applied stress and dislocations piled up in interface(DPI). The energy due to DPI is found by modifying the result of Dundurs and Mura[4]. The volume free energies caused by both applied stress and DPI are a function of the cavity size(r) and elapsed time(t) and arise from stress relaxation in the interface. Critical radius $r^*$ and incubation time $t^*$ to maximise Helmholtz free energy is found in present analysis. Also, kinetics of cavity formation are investigated using the results obtained by Riede [7]. The incubation time is defined in the analysis as the time required to satisfy both the thermodynamic and kinetic conditions. Through the analysis it is found that 1) strain energy caused by the applied stress does not contribute significantly to the thermodynamic and kinetic conditions of a cavity formation, 2) in order to satisfy both thermodynamic and kinetic conditions, critical radius $r^*$ decreases or holds constant with increase of the time until the kinetic condition(eq. 2.3) is satisfied. there for the cavity may not grow right after it is formed, as postulated by Harris [15], and Ishida and Mclean [16], 3) the effects of strain rate exponent (m), material constant $\sigma$0, volume fraction of the particle to matrix(f)and particle size on the incubation time are estimated using material constants of the copper as matrix.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.10
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• pp.1455-1466
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• 2002

This research focuses on functionalism in American fashion designs which have become the center of public attention in recent. First, documentary studies about how functionalism, which originated in Europe in the beginning of the 20th century, has been developed throughout the 20th century were preceded Second, content analysis was done for the articles, including the word ‘unction’,‘utility’ and ‘practical’in the New York Times and American Vogue from January 1990 to January 2001. As a result, functionalism in 1990s has been developed in different ways from the mechanical, organic, and mea analogies of functionalism in the beginning of 20th century. It doesn't belong to an analogy but has the fused characteristics of those three analogies. It can be classified into techno functionalism influenced by new technology, pure functionalism related to minimalism, sports casual functionalism for those who are crazy about the speed and sports and enjoy the freedom and comfort, and symbolic functionalism which stresses Zen style. More casual manners of formal wear are distinct elements in functionalist fashion design in 1990s. It leads to strong expressions of sports casual functionalism, which plays a great role in sportswear industry of American fashion design. The American fashion designers who were mentioned often in the articles were Donna Karan, Calvin Klein, Ralph lauren and Tommy Hilfiger. As well as their works have common formative features based on functionalism, each of them shows his/her own strung color. A]1 of these designers make American fashion design, which can be defined as casual wear or sportswear, very popular worldwide based on the developed American functionalism. Functionalism considering practical and conceptional functions will continue in coming century and techno functionalism and sports casual functionalism in future fashion designs wilt be expressed more strongly with new technology and casual trends of life style.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.6
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• pp.913-922
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• 1987

In this paper the solidification phenomena at the molten pool has been modeled and simulated in terms with the one dimensional unsteady-state heat transfer of the solid and molten phase and the pressure distribution in the solid phase for the twin-roller continuous casting of Sn-15% Pb. The further purpose of this study was to effectively analyze the thermal and mechanical deformation of roll applying the results of the heat transfer and the pressure distribution to the boundary conditions. The strip thickness of rapidly solidified metallic strip decreases with increasing angular velocity of the roller and with increasing initial roll gap. For this reason the roll spacing and angular velocity of the rolls are considered to be main variables. The recommended optimal casting regimes for continuous strip dimensions is near 0.8mm-1.0mm in thickness at the given angular velocity .omega.=2.0 rad/sec. Results of the experiment using Sn-15% Pb are compared with model predictions. The calculated roll deformation has been in good agreement with the observed value of roll deformatiion. All the deformation. All the deformation of the roller is within the elastic range, the plastic yielding are not occured. However, these elastic stresses are sufficient to take place of the shortened roller life by the thermal fatigue and a notch fatigue. The higher cooling rates were obtained by a twin-roller quenching technique. Also the quenched microstructure of the rapidly solidified shell was verified.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.7 s.124
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• pp.572-578
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• 2007

Two stroke low speed diesel engines are widely used for marine propulsion or as power plant prime mover. These engines have many merits which includes higher thermal efficiency, mobility and durability. Yet various annoying vibrations occur sometimes in ships or at the plant itself. Of these vibrations, torsional vibration is very important and dictates a careful investigation during the engme's initial design stage for safe operation. With the rule and limit on torsional vibration in place, shaft strength fatigue due to torsional vibration however demands further analysis which possibly can be incorporated in the classification societies' rule and limit. In addition, the shaft's torsional vibration stresses can be calculated equivalently from accumulated fatigue cycles number due to transient torsional vibration in time domain. In this paper, authors suggest a new estimation method combined with Palmgren-Miner equation. A 6S70MC-C ($25,320ps{\times}91rpm$) engine for ship propulsion was selected as a case study. Angular velocity was measured, instead of shaft's strain, for simplified measurement and it was converted to torsional vibration stress for accumulated fatigue cycle numbers in shafting life time. Likewise, the accumulated fatigue calculation was compared with shaft fatigue strength limit. This new method can be further realized and confirmed in ship with two stroke low speed diesel engine.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.261-275
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• 2013

This study aims to explore the utilizing experience of public support service of the single mothers, who have been assessed as inability in aspect of labor. For this purpose of this study, we had in-depth interview five interviewees who had adolescent children or non-adult children. The participants were from 20s to 50s. From the outcomes of this study, we figured out that they had attempted to escape from the poor realities of life and to help the family budget through their work. However, they could not have plans to fulfill their aims, because of the unhealthy body conditions, the high working costs, the burdens for parenting or child-rearing, and the low levels of working ability. It has been shown that their parenting stresses and depressions from their hard realities have been reinforced, and those psycho-emotional pressures have been projected to connect with the inappropriate disciplines and parenting or child-rearing. And it has been reinforced through utilizing public support service. Consequently, they have become chronic through the repeated disappointment and unhealthy psycho-emotional condition. In this study, we discussed and proposed the labor policies and practical suggestions which have had a close relationship with the efficient judgement systems for work inability.