• Journal of Animal Science and Technology
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• 제48권5호
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• pp.663-670
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• 2006

국내에서 제조된 서방출형 유전자재조합 돼지 성장호르몬 (porcine somatotropin; pST)이 돼지의 성장과 등지방두께에 미치는 영향을 구명하기 위해 평균체중이 78kg인 랜드레이스 거세돈 48두를 공시하여 대조구, 4:1제형 rpST구 (6회 투여), 1:1제형 rpST구 (4회 투여), 4:1제형 rpST구 (4회 투여)에 각각 12두씩 배치하였다. 대조구는 pST를 투여하지 않았고, rpST 처리구는 1주일에 1회, 목 근육에 서방형 제재를 주입하였는데, 6회 투여구는 개시부터 2주까지는 100mg을, 3주부터 6주까지는 125mg을, 4회 투여구는 개시부터 2주까지는 100mg을, 3주부터 4주까지는 125mg을 투여하였다. 시험사료는 라이신 함량이 0.9%인 시판 육성돈사료를 무제한 급여한 결과 (주) LG 화학에서 제조한 서방출형 유전자재조합 pST는 증체량 및 사료요구율을 개선시켜 생산성 향상과 등지방두께 감소로 육질이 향상되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.557-561
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• 2005

The present study was undertaken to investigate the effects of weekly administration of implant type recombinant porcine somatotropin (rpST) on the performance and carcass characteristics in finishing pigs. A total of 120 crossbred (Landrace${\times}$Yorkshire${\times}$Duroc) pigs were employed for 11 weeks in a growth trial in experiment. A rpST designed to implant every 7 d was used. Forty pigs, each weighing 75 kg, were allocated into three rpST treatments; control (CONT), implant of rpST from 75 kg (TRT1) or 90 kg (TRT2) of body weight. The CONT pig and pigs in TRT2 from 75 kg to 90 kg were treated without rpST but with placebo. In rpST-treated pigs, each 100 mg and 125 mg of the equivalent rpST was implanted from live weight of 75 kg to 90 kg and from 90 kg to market weight, respectively. Half of the pigs from each treatment were marketed at live weight of 110 kg and the rest at 130 kg. All pigs were allowed ad libitum access to a commercial feed containing 0.94% and 0.88% of lysine from 75 to 110 kg, 110 to 130 kg of body weights, respectively. rpST had no effect on daily gain, while feed efficiency was improved by 7 to 13% (p<0.05) in the rpST-treated groups compared with the CONT. Compared with the CONT, backfat thickness was decreased by 12% (p<0.05) in TRT1 at 110 kg of market weight, and by 23 to 32% (p<0.05) in the rpST-treated groups at 130 kg of market weight, respectively. Lean muscle rate tended to be higher in TRT1 at both 110 kg and 130 kg of market weight, and carcass fat percentage in the rpST-treated groups was decreased by 33 to 46% (p<0.05) compared with the CONT.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.428-432
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• 2003

The technical combination of RP and RT has a potential for rapid manufacturing of three-dimensional parts. In the present work a new RP system, $VLM-_{ST}$, is proposed to manufacture net shapes of 3D prototypes. ㅁ human head shape and a kob shape are manufactured by the $VLM-_{ST}$ apparatus. In addition, a new RT technology, which utilizes a RTV molding technique and a triple reverse process technique, is proposed to manufacture net shapes of 3D plastic parts using prototypes of $VLM-_{ST}$. A plastic part of the knob shape os produced by the proposed RT technology. The combination of the proposed RP and RT enables the manufacturing of a plastic knob within two days.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.536-539
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• 2002

The reverse engineering (RE) technology can quickly generate 3D point cloud data of an object by capturing the surface of a model using a 3D scanner. In the rapid prototyping (RP) technology, prototypes are rapidly produced from 3D CAD models in a layer-by-layer additive basis. In this paper, a physical human head shape is duplicated using a new RP process, the Transfer-type Variable Lamination Manufacturing process using expandable polystyrene foam sheet (VLM-ST), after the point cloud data of a human head shape measured from 3D SNX scanner are converted to STL file. From the duplicated human head shape, it has been shown that the VLM-ST process in connection with the 3D scanner is a fast and efficient process in that shapes with free surface, such as the human head shape, can be duplicated with ease. Considering the measurement time and the shape duplication time, the use of 3D SNX scanner and the VLM-ST process is expected to reduce the lead-time fur the development of new products in comparison with the other existing RE-RP connected manufacturing systems.

• 소성∙가공
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• 제11권4호
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• pp.323-331
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• 2002

The combination of rapid prototyping(RP) and rapid tooling(RT) has a potential for rapid manufacturing of three-dimensional parts. In the present study, a new RP system transfer type Variable Lamination Manufacturing using Expandable Polystyrene Foam (VLM-ST), is proposed to fabricate net shapes of three-dimensional prototypes. Various three-dimensional parts, such as a knob shape and a human head shape, are manufactured by the VLM-ST apparatus. In addition, a new rapid tooling technology, which utilizes a room temperature vulcanizing (RTV) molding technique and a triple reverse process technique, is proposed to manufacture net shapes of three-dimensional plastic parts using the prototypes of VLM-ST. A plastic part of the knob shape is produced by the proposed RT technology. The combination of the proposed RP and RT enables the manufacture of a plastic knob within two days.

• 한국정밀공학회지
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• 제22권2호
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• pp.202-209
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• 2005

A new effective thick-layered RP process, Transfer-type Variable Lamination Manufacturing using expandable polystyrene foam (VLM-ST) has been developed with thick layers and sloped surfaces. VLM-ST has the innate advantages by virtue of its working principle: high building speed, low cost for introduction and maintenance of VLM-ST apparatus, little staircase surface irregularities of parts. Despite these advantages in VLM-ST, the surface roughness of VLM-ST parts is still inadequate to be used as RP master patterns for rapid tooling (RT). This paper describes the systematic and effective methodology to remove the laminated pattern and improve the surface roughness for VLM-ST parts. From the results of surface finishing of VLM-ST parts, it can be seen that the laminated pattern is completely removed and the surface characteristics such as surface roughness, surface hardness, and paintability are improved.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.50-53
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• 2003

Most companies use technologies such as stereolithography, selective laser sintering, and fused deposition modeling to make parts for such small consumer products as telephones, heads, and shoes. The largest part that the existing RP systems can make is only 600 mm in length. Because most RP systems build parts by depositing, solidifying, or sintering material point-by-point, making larger objects takes a long time. and in many cases, large objects won't fit the build size. A new effective thick-layered RP process. Transfer type Variable Lamination Manufacturing using expandable polystyrene foam (VLM-ST) has been developed with thick layers and sloped surfaces. In this paper, a scaledown model of F16 Fighter with the length of 800 mm is rapidly fabricated using the VLM-ST process. In order to build a CAD model of F16 larger than 600 mm in length, the approach in VLM-ST is to build larger parts in multiple sub-parts and then glue them together. The fabricated result shows that the VLM-ST process employing thick layers and sloped surfaces is adequate for creating the real-sized large objects in the diverse fields such as automobiles, electric home appliances, electronics. and etc.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2717-2722
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• 2013

Background: The objective of this research is the computed axial tomography (CT) imaging grading of radiation induced pneumonitis (RP) and its correlation with clinical and radiotherapeutic parameters. Materials and Methods: The chest CT films of 20 patients with non-small cell lung cancer who have undergone threedimensional conformal radiation therapy were reviewed. The proposed CT grading of RP is supported on solely radiological diagnosis criteria and distinguishes five grades. The manifestation of RP was also correlated with any positive pre-existing chronic obstructive pulmonary disease (COPD) history, smoking history, the FEV1 value, and the dosimetric variable V20. Results: The CT grading of RP was as follows: 3 patients (15%) presented with ground glass opacity (grade 1), 9 patients (45%) were classified as grade 2, 7 patients (35%) presented with focal consolidation, with or without elements of fibrosis (grade 3), and only one patient (5%) presented with opacity with accompanying atelectasis and loss of pulmonary volume (grade 4). Both univariate and multivariate analysis revealed as prognostic factors for the radiological grading of RP the reduction of FEV1 and the V20 (P=0.026 and P=0.003, respectively). There was also a significant (P<0.001) correlation of radiological grading of RP with FEV1 and V20 (spearman rho 0.92 and 0.93, respectively). Conclusions: The high correlation of the proposed radiological grading with the FEV1 and the V20 is giving a satisfactory clinical validity. Although the proposed grading scale seems relevant to clinical practice, further studies are needed for the confirmation of its validity and reliability.

• 한국CDE학회논문집
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• 제8권4호
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• pp.212-221
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• 2003

In order to reduce the lead-time and cost, the technology of rapid prototyping (RP) has been widely used. A new rapid prototyping process, transfer-type variable lamination manufacturing process by using expandable polystyrene foam (VLM-ST), has been developed to reduce building time, apparatus cost and additional post-processing. At the same time, VLM Slicer, the CAD/CAM software for VLM-ST has been developed. In this study, algorithms for accuracy improvement of VLM-ST, which include offset and overrun of a cutting path and generation of a reference shape are developed. Offset algorithm improves cutting accuracy, overrun algorithm enables the VLM-ST process to make a shape of sharp edge and reference shape generation algorithm adds additional shape which makes off-line lamination easier. In addition, proposed algorithms are applied to practical CAD models for verification.

• 한국CDE학회논문집
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• 제7권3호
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• pp.148-156
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• 2002

Most Rapid Prototyping (RP) processes adopt a solid Computer Aided Design (CAD) model, which will be sliced into thin layers of constant thickness in the building direction. Each cross-sectional layer is successively deposited and, simultaneously, bonded onto the previous layer; and eventually the stacked layers from a physical part of the model. A new RP process, the transfer-type Variable Lamination Manufacturing process using expandable polystyrene foam sheet (VLM-ST), has been developed to reduce building time and to improve the surface finish of parts with the thick layers and a sloping surface. This paper describes the generation of Unit Shape Layer (USL), the cutting path data of the linen. hotwire cutter for the VLM-ST process. USL is a three-dimensional layer with a thickness of more than 1 mm and a side slope, and it is the basic unit of cutting and building in the VLM-ST process. USL includes data such as layer thickness, positional coordinates, side angles of each layer, hotwire cutting speed, the heat input to the hotwire, and reference shape. The procedure of generating USL is as follows: (1)Generation of the mid-slice from the CAD model, (2)Conversion of the mid-slice into a simply connected domain, (3)Generation to the reference shape for the mid-slice, (4)Calculation of the rotation angle of the hotwire of the cutting system.