• Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.41-44
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• 2013

We developed a poly(butylene succinate) (PBS) indicator plate and isolated a marine bacterial colony capable of biodegrading PBS based on the appearance of a clear zone. Growth of the PBS-2 isolate was observed over 4 days of culture at $37^{\circ}C$ in PBS-tryptone basal liquid medium, but not in PBS-deprived control medium. The PBS-2 isolate was named Paenibacillus sp. PBS-2 based on 16S rDNA gene sequencing. The PBS-biodegrading marine bacterium isolated in this study will contribute to the effective management of PBS waste problems in marine environments.

• Journal of Adhesion and Interface
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• v.15 no.1
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• pp.14-21
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• 2014

In the present work, PLA/PBS blends with poly(lactic acid) (PLA) and poly(butylene succinate) (PBS) at different contents were processed by using a twin-screw extruder and an injection molding machine, and then their mechanical, thermal and morphological properties were investigated. The mechanical properties such as flexural strength, flexural modulus, tensile strength and tensile modulus and thermal properties such as melting behavior, dynamic mechanical thermal properties and thermal stability significantly depended on the contents of PLA and PBS. However, the heat deflection temperature of the blends was not significantly influenced by the contents of PLA and PBS. Also, the fracture surfaces of PLA/PBS blends were changed from a brittle pattern to a ductile pattern with increasing the PBS contents.

• Macromolecular Research
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• v.16 no.3
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• pp.218-223
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• 2008

In order to obtain crosslinked poly(butylene succinate) (PBS) foams with a closed-cell structure, a commercial-grade PBS was first modified in the melt using two different branching agents to increase the melt viscosity. The rheological properties of the branched and crosslinked PBS were examined by varying the amount of the branching agents. The complex viscosity of the crosslinked PBS increased with increasing amount of the branching agent. However, it decreased with increasing frequency. When 2 phr of the branching agent was added to PBS, the storage modulus (G') was higher than the loss modulus (G") throughout the entire frequency range, showing that the addition of a branching agent increases the melt viscosity and elasticity of PBS effectively. Closed-cell PBS foams were prepared by mixing the chemical blowing agent with the crosslinked PBS. The effect of the foaming conditions such as temperature and time, and the amount of the crosslinking agent on the structure of the expanded PBS foams were also investigated.

• Macromolecular Research
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• v.10 no.2
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• pp.108-114
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• 2002

Poly(butylene succinate) (PBS) prepolymers were prepared by the condensation polymerization of 1,4-butanediol (1,4-BD) and succinic atid (SCA) in the presence of titanium (VI) isoproxide(TPI) catalyst. The PBS prepolymers reacted with 1,4-BD or SCA to obtain hydroxyl or carboxylic acid group terminated PBS. High molecular weight linear or branched PBS was synthesized by a coupling reaction between hydroxyl and carboxylic acid group terminated PBS, or by a branching reaction between carboxylic acid group terminated PBS and glycerol as a branching agent. The weight average molecular weight of the prepared linear or branched PBS was in the range of 100,000-220,000. Both melting point and thermal stability of the high molecular weight linear and branched PBSs were somewhat higher than those of general PBS. From a tensile behavior by Instron test, modulus, tensile strength and elongation at break improved with increase in the molecular weight of the prepared PBS through the coupling or the branching reaction. In particular, the high molecular weight linear PBS had about 2.5 times higher value in modulus than the branched one.

• The Journal of Korean Physical Therapy
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• v.28 no.1
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• pp.22-26
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• 2016

Purpose: The purpose of this study was to evaluate the relation between PBS scores and GMFCS levels and to examine whether pediatric balance scale (PBS) scores were useful for predicting gross motor functional classification system (GMFCS) levels in children with cerebral palsy. Methods: This cross-sectional study was performed conducted for to evaluatione of PBS and GMFCS using in 26 children with cerebral palsy (16 males and 10 females with GMFCS level I to III). PBS total and item scores at different levels of GMFCS were measured. Results: The hHigh PBS item average scores obtained from standing and postural change dimensions except sitting dimension were observed at the low levels of GMFCS and these results were statistically significant (p<0.05). The relation between PBS (standing and postural change dimensions) and GMFCS levels were was significantly different, except the relation between PBS sitting dimension and GMFCS levels showing a ceiling effect. Conclusion: GMFCS is designed to for classificationy of gross motor functions emphasizing on walking movement and PBS is was developed to for evaluatione of functional balance. Based on the results of this study showing high relation between GMFCS levels and PBS scores, PBS scores can be used for predicting GMFCS levels.

• Korea-Australia Rheology Journal
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• v.19 no.3
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• pp.125-131
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• 2007

Biodegradable polymeric blends are expected to be widely used by industry due to their environmental friendliness and comparable mechanical and thermal properties. Poly (lactic acid) (PLA) and poly (butylene succinate) (PBS) are such biodegradable polymers which aim to replace commodity polymers in future applications. Since cost and brittleness of PLA is quite high, it is not economically feasible to use it alone for day to day use as a packaging material without blending. In this study, blends of PLA and PBS with various compositions were prepared by using a laboratory-scale twin-screw extruder at $180^{\circ}C$. Morphological, thermal, rheological and mechanical properties were investigated on the samples obtained by compression molding to explore suitability of these compositions for packaging applications. Morphology of the blends was investigated by scanning electron microscopy (SEM). Morphology showed a clear phase difference trend depending on blend composition. Modulated differential scanning calorimetry (MDSC) thermograms of the blends indicated that the glass transition temperature ($T_g$) of PLA did not change much with the addition of PBS, but analysis showed that for PLA/PBS blend of up to 80/20 composition there is partial miscibility between the two polymers. The tensile strength and modulus were measured by the Instron Universal Testing Machine. Tensile strength, modulus and percentage (%) elongation at break of the blends decreased with PBS content. However, tensile strength and modulus values of PLA/PBS blend for up to 80/20 composition nearly follow the mixing rule. Rheological results also show miscibility between the two polymers for PBS composition less than 20% by weight. PBS reduced the brittleness of PLA, thus making it a contender to replace plastics for packaging applications. This work found a partial miscibility between PBS and PLA by investigating thermal, mechanical and morphological properties.

• Journal of the Korean Society for Railway
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• v.11 no.1
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• pp.26-32
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• 2008

This paper discusses WBS (Work Breakdown Structure) that is known for technique of basic project management. The WBS use in domestic industries often exhibit errors in Its structure. The most common serious error is space-oriented breakdown structure of PBS (Product Breakdown Structure) that becomes the core element of the WBS. This paper proposes a method to correct the problem of space-oriented breakdown structure constructed in domestic railroad industry. DSM method was adopted to construct PBS containing function-oriented structure. The proposed process and method will contribute to minimize time that take to construct an accurate and useful PBS.

• Korean Journal of Childcare and Education
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• v.16 no.5
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• pp.173-200
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• 2020

Objective: The goal of this study was to explore the implementation status of positive behavior support(PBS) for child care and education teachers and special education teachers at inclusive settings, and to investigate support needs of both teachers for improving the implementation of PBS. Methods: This study made up 405 surveys for child care and education teachers and special education teachers in 45 inclusive settings from July to August in 2019. A total of 244 surveys(60.2%) were completed and returned. Results: Special education teachers were statistically higher than child care and education teachers in the implementation of the center based level 1, the small group based level 2, and the individual based level 3 of PBS. In open-ended responses, when implementing PBS, the two groups of teachers had difficulties in getting knowledge about how to instruct preschoolers and implementing PBS. Both groups of teachers wanted the education and the training opportunities for PBS at first, and to 'reduce the teacher-to-child ratio'in the public support system. Conclusion/Implications: Based on the results, suggestions were discussed on how to improve the implementations of PBS of child care and education teachers and special education teachers at inclusive settings.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2012.05a
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• pp.30-44
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• 2012

지난 96년 PBS제도가 시행되면서, 많은 연구에서 PBS제도의 문제점을 제시해 왔다. 선행 연구에서는 인건비 확보를 위한 과도한 경쟁으로 연구활동의 안정성 저하 및 불안감 조성, 기관 내 외 연구자간의 경쟁구도 심화로 상호협력을 통한 융합연구의 어려움, 관리 운영체계의 제약요인으로 인한 제도 확산은 정부출연연구기관의 성과를 저하시킨다고 지적하였다. 하지만 PBS제도 도입당시의 기대효과였던 기관의 자율성 강화, 연구책임자 책임성 강화, 사업관리의 투명성 강화는 정부출연연구기관의 성과를 높이는 효과를 가져올 수 있다. 따라서 본 연구에서는 PBS제도 도입 후 15년이 경과한 현재 PBS제도가 출연연구기관의 연구과제 수행 성과에 어떠한 영향을 미치는지에 대한 실증분석을 하였다. 기초기술연구회 소속 13개 기관을 대상으로 질적 논문성과를 분석해본 결과, 기관이 수행한 과제의 PBS제도는 논문성과에 영향을 미치지 않는 것으로 나타났다. 하지만 수행 과제의 기술적 특성을 기술분야별, 기술단계별로 나눠보았을 경우, 기술단계별 구분에서 기초기술연구회 소속 정부출연연구기관의 논문성과는 기초기술 단계의 과제를 수행하였을 경우 높은 질적 논문성과를 보여주는 것으로 나타났다.

• Journal of the Korean Society of Physical Medicine
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• v.5 no.2
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• pp.281-288
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• 2010

Purpose : The purpose of this study was to examine the correlation between Pediatric Balance Scale(PBS) and Gross Motor Function Measurement(GMFM) with cerebral palsy(CP) children. Methods : 31 ambulatory children with CP were recruited for this study. PBS is a modified version of the Berg’s Balance Scale to access the children with motor impairments. To access the motor functions that directly influence to the functional independence of the ambulatory CP children, total scores of standing category and walking/running/jumping category of GMFM were selectively compared with PBS score by Spearman correlation coefficient analysis. Results : The results revealed high correlation between PBS and GMFM scores both in standing and walking/running/jumping categories(r=.9). Conclusions : Therefore, this study indicates that PBS can be applied not only as a tool to access balance, but also as a measurement to predict and access the level of standing and ambulatory related functions of children with CP.