• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.81-86
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• 1999

Nowadays, as the development period of new products becomes shorter and consumer's requirement is more various, the importance of Rapid Protytyping Technology has been rapidly increased. Rapid Protytyping makes protytypes or functional parts directly using the 3D CAD data. But RP machines can make protytype in limit size. But RP machines can make protytype in limit size. For making large size protytype, we slice solid, which is made of STL file, and then glue sliced solid. This paper is concerned with slicing solid on STL file.

• Korean Journal of Veterinary Research
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• v.51 no.3
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• pp.233-237
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• 2011

The objective of this study was to evaluate the duration of retained placenta (RP) on postpartum diseases and culling in dairy cows. Data were collected from 456 Holstein cows between 2008 and 2010. RP (${\geq}$ 24 h after parturition) and postpartum diseases were diagnosed by farm managers and a veterinarian according to standardized definitions. The overall incidence rate of RP was 14.0%, and the incidence rate of RP with fourth and higher parity was two times that of cows having offspring for the first time. The duration of RP was 2 to 15 days with a mean of 6.8 days, except for cases of fourth and higher parity which had a mean of 10.5 days. A total of 63% of cows with RP had postpartum diseases. Among the cows diagnosed with RP, 23.4% developed metritis, and of those, 35.3% developed endometritis or pyometra. A total of 25% (n = 16) cows with RP were culled within 60 days in milk (DIM) and of those culled, 75% (n = 12) had postpartum diseases. These results suggest that RP increases the risk of postpartum diseases such as metritis and mastitis and is a culling hazard up to 60 DIM.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.1B
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• pp.45-54
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• 2003

In the Protocol-Independent Multicast Sparse Mode(PIM-SM), we need a careful selection scheme for the Rendezvous Point(RP) which influences much on the QoS due to the delay among multicast group members and packet loss The QoS based RP selection schemes choose RPs which satisfy the restriction conditions such as bandwidth, delay, and other QoS parameters In this paper, we propose a new RP selection scheme which is a variation of the group-based RP selection scheme The new algorithm, MCT(Maximum Cross Tree), is implemented by taking advantages of the topology-based selection scheme and the group-based selection scheme as well In order to verify the proposed algorithm, we first measure the multicast traffic data of the Virtual Conference System implemented on the IPv6 network via KOREN, then expand the results to two types of network models and analyze the performance by computer simulation.

• Journal of Chest Surgery
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• v.20 no.4
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• pp.688-694
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• 1987

At the Dept. of Thoracic and Cardiovascular Surgery of Pusan National University Hospital, postoperative cardiac catheterizations were performed in 12 patients of ventricular septal defect with severe pulmonary hypertension [Pp/Ps>0.75], who were operated during the period from July 1981 to Dec. 1986. The mean age of the patients preoperatively was 12.4 [range: 4-18] year-old and the mean follow-up duration was 25.8 [range: 8-53] month per patient. In comparison with the preoperative data, the systolic pulmonary artery pressure [SPAP] was decreased from 103.6*18.4 to 70.4*35.9 mmHg [p<0.01] and the Pp/Ps was decreased from 0.89*0.10 to 0.58*0.27 [p<0.01]. But the Rp/Rs and Rp were not meaningfully changed, from 0.31*0.16 and 7.6*0.4 unit to 0.41*0.32 and 8.0*6.6 unit, respectively. The preoperative Qp/Qs was bellow 2.0[mean: 1.6] in 3 out of 4 cases whose postoperative Rp/Rs and Rp were above 0.75 and 15 unit, respectively. On the contrary, the preoperative Qp/Qs was above 2.0 [mean: 3.5] in all of the 8 cases, whose postoperative Rp/Rs and Rp were below 0.50 and 10 unit, respectively.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.2
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• pp.5-14
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• 2002

Internet becomes very common tool far communication and data sharing. Virtual readily(VR) on web browser, and virtual prototyping and virtual manufacturing is widely used in many engineering fields. The reduction of overall development process and error minimization during data conversion becomes very crucial where sharing data via Internet and VR. This paper deals with the advantage and disadvantage of VRML format used in RP(Rapid Prototyping), and a software for RP data preparation is developed. If VRML format as an international standard for VR, is replaced with STL format, the weak points of STL formal can be overcome and the technique related to virtual prototyping and virtual manufacturing can be addressed more systematically by sharing the data. The system developed in this work shows a good window to get access to a mare realistic observation of an object for an RP system from a long remote sites in a more systematic way.

• Journal of Internet Computing and Services
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• v.3 no.5
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• pp.87-94
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• 2002

This paper proposes a group key management protocol for a secure of all the multcast user in PIM-SM multicast group communication. Each subgroup manager gives a secure key to it's own transmitter and the transmitter compress the data with it's own secure key from the subgroup manager, Before the transmitter send the data to receiver, the transmitter prepares to encrypt a user's service by sending a encryption key to the receiver though the secure channel. after checking the user's validity through the secure channel, As the transmitter sending a data after then, the architecture is designed that the receiver will decode the received data with the transmitter's group key, Therefore, transmission time is shortened because there is no need to data translation by the group key on data sending and the data transmition is possible without new key distribution at path change to shortest path of the router characteristic.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7371-7375
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• 2014

Background: Concurrent chemo-radiotherapy is the recommended standard treatment modality for patients with locally advanced lung cancer. The purpose of three-dimensional conformal radiotherapy (3DCRT) is to minimize normal tissue damage while a high dose can be delivered to the tumor. The most common dose limiting side effect of thoracic RT is radiation pneumonia (RP). In this study we evaluated the relationship between dose-volume histogram parameters and radiation pneumonitis. This study targeted prediction of the possible development of RP and evaluation of the relationship between dose-volume histogram (DVH) parameters and RP in patients undergoing 3DCRT. Materials and Methods: DVHs of 41 lung cancer patients treated with 3DCRT were evaluated with respect to the development of grade ${\geq}2$ RP by excluding gross tumor volume (GTV) and planned target volume (PTV) from total (TL) and ipsilateral (IPSI) lung volume. Results: Were admitted statistically significant for p<0.05. Conclusions: The cut-off values for V5, V13, V20, V30, V45 and the mean dose of TL-GTV; and V13, V20,V30 and the mean dose of TL-PTV were statistically significant for the development of Grade ${\geq}2$ RP. No statistically significant results related to the development of Grade ${\geq}2$ RP were observed for the ipsilateral lung and the evaluation of PTV volume. A controlled and careful evaluation of the dose-volume histograms is important to assess Grade ${\geq}2$ RP development of the lung cancer patients treated with concurrent chemo-radiotherapy. In the light of the obtained data it can be said that RP development may be avoided by the proper analysis of the dose volume histograms and the application of optimal treatment plans.

• Radiation Oncology Journal
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• v.30 no.1
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• pp.43-48
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• 2012

Purpose: To develop the dose volume histogram (DVH) management software which guides the evaluation of radiotherapy (RT) plan of a new case according to the biological consequences of the DVHs from the previously treated patients. Materials and Methods: We determined the radiation pneumonitis (RP) as an biological response parameter in order to develop DVH management software. We retrospectively reviewed the medical records of lung cancer patients treated with curative 3-dimensional conformal radiation therapy (3D-CRT). The biological event was defined as RP of the Radiation Therapy Oncology Group (RTOG) grade III or more. Results: The DVH management software consisted of three parts (pre-existing DVH database, graphical tool, and $Pinnacle^3$ script). The pre-existing DVH data were retrieved from 128 patients. RP events were tagged to the specific DVH data through retrospective review of patients' medical records. The graphical tool was developed to present the complication histogram derived from the preexisting database (DVH and RP) and was implemented into the radiation treatment planning (RTP) system, $Pinnacle^3$ v8.0 (Phillips Healthcare). The software was designed for the pre-existing database to be updated easily by tagging the specific DVH data with the new incidence of RP events at the time of patients' follow-up. Conclusion: We developed the DVH management software as an effective tool to incorporate the phenomenological consequences derived from the pre-existing database in the evaluation of a new RT plan. It can be used not only for lung cancer patients but also for the other disease site with different toxicity parameters.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.1 s.94
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• pp.95-107
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• 1999

The design models of a new product in general are created using clay models or wooden mock-ups. The reverse engineering(RE) technology enables us to quickly create the CAD model of the new product by capturing the surface of the model using laser digitizers or coordinate measuring machines. Rapid prototyping (RP) is another technology that can reduce the product development time by fabricating the physical prototype of a part using a layered manufacturing technique. In reverse engineering process, however, the digitizer generates an enormous amount of point data, and it is time consuming and also inefficient to create surfaces out of these data. In addition, the surfacing operation takes a great deal of time and skill and becomes a bottleneck. In rapid prototyping, a faceted model called STL file has been the industry standard for providing the CAD input to RP machines. It approximates the CAD model of a part using many planar triangular patches and has drawbacks. A novel procedure that overcomes these problems and integrates RE with RP is proposed. Algorithms that drastically reduce the point clouds data have been developed. These methods will facilitate the use of reverse engineered geometric data for rapid prototyping, and thereby will contribute in reducing the product development time.

• International Journal of Highway Engineering
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• v.20 no.2
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• pp.119-126
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• 2018

PURPOSES : The purpose of this study is to develop a crash prediction model at signalized intersections, which can capture the randomness and uncertainty of traffic accident forecasting in order to provide more precise results. METHODS : The authors propose a random parameter (RP) approach to overcome the limitation of the Count model that cannot consider the heterogeneity of the assigned locations or road sections. For the model's development, 55 intersections located in the Daejeon metropolitan area were selected as the scope of the study, and panel data such as the number of crashes, traffic volume, and intersection geometry at each intersection were collected for the analysis. RESULTS : Based on the results of the RP negative binomial crash prediction model developed in this study, it was found that the independent variables such as the log form of average annual traffic volume, presence or absence of left-turn lanes on major roads, presence or absence of right-turn lanes on minor roads, and the number of crosswalks were statistically significant random parameters, and this showed that the variables have a heterogeneous influence on individual intersections. CONCLUSIONS : It was found that the RP model had a better fit to the data than the fixed parameters (FP) model since the RP model reflects the heterogeneity of the individual observations and captures the inconsistent and biased effects.