• Journal of Institute of Convergence Technology
• /
• v.10 no.1
• /
• pp.7-12
• /
• 2020

We describe a efficient surface reconstruction method that reconstructs a 3D manifold polygonal mesh approximately passing through a set of 3D oriented points. Our algorithm includes 3D convex hull, octree data structure, signed distance function (SDF), and marching cubes. The 3D convex hull provides us with a fast computation of SDF, octree structure allows us to compute a minimal distance for SDF, and marching cubes lead to iso-surface generation with SDF. Our approach gives us flexibility in the choice of the resolution of the reconstructed surface, and it also enables to use on low-level PCs with minimal peak memory usage. Experimenting with publicly available scan data shows that we can reconstruct a polygonal mesh from point cloud of sizes varying from 10,000 ~ 1,000,000 in about 1~60 seconds.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.30B no.12
• /
• pp.31-39
• /
• 1993

In the playback signal processing of a digital magnetic recording system, the major signal processing processes consist of pulse equalization. pulse detection, clock recovery, and data recovery. Equalizer which compensates interference occurrde between pulses recorded in high density on a magnetic media is realized by pulse slimming method, and pulse detection by a integrating detector. Clock recovery from the detector output was accomplished by using PLL. and data recovery to reduce noise effects was carried out by utilizing the three sampling clocks recovered in clock recovery process. In this paper these processes are implemented in hardware and its performance is evaluated by experimenting with a commercial DAT. It was found that the playback signal processor proposed is suitable to the practical high density magnetic recording system.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.5
• /
• pp.1272-1290
• /
• 2013

Privacy-preserving collaborative filtering schemes are becoming increasingly popular because they handle the information overload problem without jeopardizing privacy. However, they may be susceptible to shilling or profile injection attacks, similar to traditional recommender systems without privacy measures. Although researchers have proposed various privacy-preserving recommendation frameworks, it has not been shown that such schemes are resistant to profile injection attacks. In this study, we investigate two memory-based privacy-preserving collaborative filtering algorithms and analyze their robustness against several shilling attack strategies. We first design and apply formerly proposed shilling attack techniques to privately collected databases. We analyze their effectiveness in manipulating predicted recommendations by experimenting on real data-based benchmark data sets. We show that it is still possible to manipulate the predictions significantly on databases consisting of masked preferences even though a few of the attack strategies are not effective in a privacy-preserving environment.

• Genomics & Informatics
• /
• v.18 no.2
• /
• pp.18.1-18.5
• /
• 2020

Finding publications that propose alternative methods to animal experiments is an important but time-consuming task since researchers need to perform various queries to literature databases and screen many articles to assess two important aspects: the relevance of the article to the research question, and whether the article's proposed approach qualifies to being an alternative method. We are currently developing a Web application to support finding alternative methods to animal experiments. The current (under development) version of the application utilizes external tools and resources for document processing, and relies on the PubAnnotation ecosystem for annotation querying, annotation storage, dictionary-based tagging of cell lines, and annotation visualization. Currently, our two PubAnnotation repositories for discourse elements contain annotations for more than 110k PubMed documents. Further, we created an annotator for cell lines that contain more than 196k terms from Cellosaurus. Finally, we are experimenting with TextAE for annotation visualization and for user feedback.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.19 no.4
• /
• pp.1062-1070
• /
• 1995

The study deals with controlling the velocity of hydraulic motor with PI controller through the control of displacement pump which has higher efficiency than valve-controlled system. This was done as follows. First, we modified original displacement pump and designed this electrohydraulic puma system. Second, after experimenting static and dynamic characteristics, we identified system parameter of approximated model. Lastly, to control the velocity of hydraulic motor we controlled the angle of the swash plate of displacement pump. Test carried out in the laboratory shows that transient and steady state response could be improved by PI controller reducing power loss.

• Proceedings of the Korean Society of Developmental Biology Conference
• /
• 2003.10a
• /
• pp.3-6
• /
• 2003

The birth of the clone animals is influencing the frontier of research of animal biotechnology. It has effects on research of animal biotechnology itself by necessitating setting of new research subjects, modifications of the strategy of ongoing research projects, and challenges to schemes formerly considered impossible. In my talk, such topics including mass production of fertile ova and oocyte maturation will be discussed. (1) Oocytes are needed for the production of a clone by nuclear transplantation. Mitochondrial DNA inherited via the oocyte are involved also in the morphogenesis. Therefore, oocytes from the same animal must be used as recipients to produce genuine clones by nuclear transplantation. Experimenting on the assumption that selective oogenesis can be avoided, and apoptosis of oocytes can be prevented, by using ovarian angiogenic factos will be introduced. (2) It is important to clarify the factors of oocytes involving in reprogramming of somatic cells. Such factors are thought to be expressed in oocytes during oogenesis and oocyte maturation. Therefore, molecular mechanisms of oogenesis and oocyte maturation must be clarified extensively. Topics in this field including our recent advances will be discussed. (중략)

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2012.11a
• /
• pp.95-96
• /
• 2012

This study makes with the environment-friendly artificial stone which doesn't use the cement and natural aggregate and increases the blast furnace slag that is the eco-friendly material that is the industrial byproduct, fly ash, and availability of the red mud and applies the coares aggregate substitute material as the cleistothecium. The experimental plan according to it indicated the compressive strength and flexural strength which is the most excellent in the mixied ratio 40% of the result degree of closeness magnetism of experimenting with the optimal mix obtained through the preceding stude.

• Fashion Information and Technology
• /
• v.2
• /
• pp.22-32
• /
• 2005

Sourcing Simulator is specialized form of software capable of providing great insight into merchandising decision making. It is relatively easy to learn and operate by reading the help menus, experimenting with inputs, and critically analyzing outputs. 1 see that it has great potential in a training program for new merchandisers to help them absorb the complexity of the numbers they must effectively use. The Sourcing Simulator, Version 1 that accompanies my textbook, Merchandising: Theory Principles, and Practice, 2nd ed. is the least complex version available. Two versions are available from [TC]2 - Retail version and The Retail/ Manufacturing version. The Retail Version is very similar to the Version 1. The Retail/ Manufacturing Version includes analysis of processes and costs in the manufacturing process as well as the merchandise planning component that we have discussed here. Sourcing Simulator is developed at North Carolina State University by Dr. Russ King, and available from Textile Clothing Technology Corporation $[TC]^2$, Cary, North Carolina.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1478-1482
• /
• 2005

Since it is a very issue that figures out a current position of mobile robots, various methods have been proposed until nowadays. This paper proposes the sensor model of RFID(Radio Frequency Identification) and position estimation algorithm for mobile robots. We designed the sensor model of RFID in experimenting repeatedly. The sensor model of RFID in this case is that of stochastics according to sensing rate. Based on this stochastic sensor model, we designed the algorithm which estimates distance and direction of RFID tag. Therefore we made sure that RFID tag is used as landmark.

• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.7
• /
• pp.148-157
• /
• 1995

This study deals with controlling the speed of Hydrostatic Transmission (HST) system throuth the control of pumping stroke of positive displacement pump using high-speed solenoid valve controlled by digital closed loop PWM method. The method which was done in this study is as follows: First, we modified original positive displacement pump and designed pumping stroke control system of HST by using the high-speed solenoid valve. Second, after experimenting static and dynamic characteristics on each signal flow, we identified system parameter of approximated model. Finally, to control the speed of HST, we controlled the angle of the swash plate of positive displacement pump by controlling the pressure in the control cylinder chamber. Test which was carried out in the laboratory shows that transient and steady state response could be improved by PID controller.