• Journal of the Korea Computer Graphics Society
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• v.11 no.2
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• pp.26-33
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• 2005

의료기기들 중 기능 영상을 보기 위해 이용되는 PET 장치에서 획득된 결과 영상은 선명하지 않기 때문에, 해부학적 구조와 기능 영상을 동시에 보기 위해서는 선명한 영상을 제공하는 CT 와 PET 장치와 하나로 통합하여 영상을 획득하게 되었다. 그래서 한번의 촬영으로 PET/CT 영상을 얻을 수 있게 된 것이다. 서로 다른 특성을 갖는 이미지를 융합하게 되면 보다 정확한 진단을 내리는데 많은 도움을 준다. 본 논문은 CT 영상에서 폐 영역을 반 자동(Semi-Auto)으로 분리한 후 PET 영상에 자동으로 융합하는 방법을 제안한다. 반 자동 폐 영역 분할을 위해 1 차원 신호 처리 기법과 Seeded Region Growing 기법을 사용한다. 수행된 폐 분리 결과는 몸의 해부학적 구조를 보기 위해 사용되는 CT 영상에서 추출한 폐 영역을 기능을 보기 위한 PET 영상에 퓨전 함으로서 진단 전문가가 보다 정확한 진단을 하는데 도움이 될 것이다. 또한 이러한 기능을 쉽게 구현하고 사용할 수 있도록 시각 프로그래밍 기법을 접목하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.401-406
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• 2008

This study can be used to produce structurally efficient recycled PET fiber from used waste PET bottles and evaluated the bond performance of the three type of recycled PET fiber and cement matrix. Also, the flexural tests were performed on concrete reinforced using the three type of recycled PET fibers. The test results showed that the recycled PET fiber was significantly increased bond strength. The flexural test results are demonstrated that recycled PET fibers improved the flexural toughness of concrete. Based on the bond and flexural test results, the bond and flexural performance of embossed type recycled PET fibers were significantly better than those of the other shape fibers.

• Resources Recycling
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• v.23 no.5
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• pp.68-79
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• 2014

Since 1990s, efforts to recycle the waste plastics by chemical methods have increased. And in accordance with this trend, attempts have become active to use the waste PET as raw materials of chemical industries. In this article, the patents and papers for development of commercial technology for feedstock recycling and high end products from PET wastes were collected and analyzed. The open patents of USA (US), European Union (EP), Japan (JP), and Korea (KR) and SCI journals from 1974 to 2013 were investigated. The patents and papers were collected using key-words and filtered by the definition of the technology. The patents and papers were analyzed by the years, countries, companies, and technologies and the technical trends were discussed in this paper.

• Resources Recycling
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• v.17 no.3
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• pp.21-28
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• 2008

Using the post-consumer waste and edge scrap mixed PET with small amount PP air filter elements of automobiles. It was studied that these mixed waste plastics of the various types of the PET were practicable for the material recycling. Various waste PET/PP plastics were collected, crushed, dried in vacuum, and extruded to recycled PET/PP chips. These chips were mixed with three kinds compatibilizers, EVA, MBS, and recycled PVB of the ratio of $3{\sim}10wt.%$ for the purpose of the compatibility for the post-consumer waste and edge scrap. We investigated mechanical and thermal properties of PET/PP mixtures which were compound with the weight ratio of compatibilizers. Compatibilizer, MBS application was showed the most excellent mechanical properties in the range of the $3{\sim}5wt.%$ EVA application was displayed good impact strength and thermal property in the range of $3{\sim}5wt.%$ Last, recycled PVB application was showed poor mechanical properties in the whole range ratio of the PVB.

• Journal of the Korea Concrete Institute
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• v.19 no.2
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• pp.233-239
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• 2007

The main objective of this study was to evaluate the effect of recycled PET fiber made from waste PET bottle on the control of plastic shrinkage cracking of cement based composites. PET is blown as a plastic material and used in a variety products such as a beverage bottle. However, waste PET bottles are thrown after the usage, raising huge problems in terms of the environment. Thus, the research on the method to recycle the PET bottles indicates important aspects in environment and economy. The method to recycle waste PET bottles as a reinforcing fiber for cement based composites is one of effective methods in terms of the recycle of waste PET bottles. In this research, the effect of recycled PET fiber geometry and length on the control of plastic shrinkage was examined through thin slab tests. A test program was carried out to understand the influence of fiber geometry, length and fiber volume fraction. Three type of recycled PET fibers including straight, twist crimped and embossed type. Three volume fraction and two fiber length were investigated for each of the three fiber geometry. Test results indicated that recycled PET fibers are effective in controlling plastic shrinkage cracking in cement based composites. In respect to effect of length of fiber, longer fiber was observed to have efficient cracking controlling with low volume fraction in same fiber geometry while shorter fiber controled plastic shrinkage cracking efficiently as addition rate increase. Also, embossed type fibers were more effective in controlling plastic shrinkage cracking than other geometry fiber at low volume fraction. But, for high volume fraction, straight type fibers were most effective in plastic shrinkage cracking controlling in cement based composites.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.77-86
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• 2002

In this study we intended to investigate properties of cement mortar with recycled PET fiber, PE fiber, and PP fiber such as slump flow, compressive strength, tensile strength, and flexural strength. As results of experiment, several properties of specimen with recycled PET fiber were little low comparing those of specimen with PE fiber and PP fiber. But if we see from point of economy and recycle of industrial wastes, it has enough reason to be used. Compressive strength of specimen with recycled PET fiber at 56 days was about 10% higher, but tensile strength and flexural strength were lower than that of no-fiber.

• Journal of the Korea Institute of Building Construction
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• v.2 no.4
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• pp.113-122
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• 2002

In this study we intended to investigate properties of cement mortar with recycled PET fiber, PE fiber. and PP fiber such as slump flow, compressive strength, tensile strength, and flexural strength. At results of experiment. several properties of specimen with recycled PET fiber were little low comparing those of specimen with PE fiber and PP fiber. But if we see from point of economy and recycle of industrial wastes, it has enough reason to be used. Compressive strength of specimen with recycled PET fiber at 55 days was about 10% higher. but tensile strength and flexural strength were lower than that of no-fiber.

• Resources Recycling
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• v.12 no.5
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• pp.16-22
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• 2003

Lightweight aggregate for concrete was manufactured from recycling the waste PET bottles (PET Bottle Lightweight Aggregate, LAPET). The qualities of LAPET and its mortar were investigated. Specific gravity and unit weight of LAPET was very low in comparison with river sand like as 1.39, 844 kg/㎥ respectively. In addition, compressive strength of concrete significantly decreased because of specific gravity of aggregate decreased with increases in containing ratio. When LAPET was contained to 25% and 50％ of river sand, compressive strength of concrete at 28 days was indicated more 30MPa. Most of LAPET was generally showed to round shape and fluidity of mortar increased significantly due to sleeking the surface texture of LAPET. On the other hand, capillary absorption of mortar with LAPET was greatly increased in comparison with that of mortar without LAPET because of LAPET was composed of singular gradation. Absorption of LAPET was 0％ because the interior structure of LAPET consists of PET like as organic high polymer. Therefore the fault of normal lightweight aggregate, absorption, will be improved. It could expect several advantages that the pollution of environment will be previously prevent and the waste resources could be recycled if LAPET is reused as aggregate for Lightweight concrete.

• Journal of the Korea Society of Computer and Information
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• v.12 no.2 s.46
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• pp.123-130
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• 2007

The aim of this study was to propose a fusion and registration method with heterogeneous small animal acquisition system in small animal in-vivo study. After an intravenous injection of $^{18}F$-FDG through tail vain and 60 min delay for uptake, mouse was placed on an acryl plate with fiducial markers that were made for fusion between small animal PET (microPET R4, Concorde Microsystems, Knoxville TN) and Discovery LS CT images. The acquired emission list-mode data was sorted to temporally framed sinograms and reconstructed using FORE rebining and 2D-OSEM algorithms without correction of attenuation and scatter. After PET imaging, CT images were acquired by mean of a clinical PET/CT with high-resolution mode. The microPET and CT images were fusion and co-registered using the fiducial markers and segmented lung region in both data sets to perform a point-based rigid co-registration. This method improves the quantitative accuracy and interpretation of the tracer.

• Journal of the Korea Concrete Institute
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• v.16 no.4 s.82
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• pp.521-528
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• 2004

In general, polymer concrete has more excellent mechanical properties and durability than Portland cement concrete, but very sensitive to heat and has large deformations. In this study, the long-term creep behaviors was predicted by the short-term creep test, and then the characteristic of creep of recycled-PET polymer concrete was defined by material and experimental variables. The error in the predicted long-term creep values is less than 5 percent for all polymer concrete systems. The filler carry out an important role to restrict the creep strains of recycled PET Polymer concrete. The creep strain and specific on using the $CaCO_3$ were less than using fly-ash. The creep increases with an increase in the applied stress, but not proportional the rate of stress increase ratio. The creep behavior of polymer concrete using recycled polyester resin is not a linear viscoelastic behavior.