Jung Lee

Virtual World Currency Value Fluctuation Prediction System Based on User Sentiment Analysis

In this paper, we present a method for predicting the value of virtual currencies used in virtual gaming environments that support multiple users, such as massively multiplayer online role-playing games (MMORPGs). Predicting virtual currency values in a virtual gaming environment has rarely been explored; it is difficult to apply real-world methods for predicting fluctuating currency values or shares to the virtual gaming world on account of differences in domains between the two worlds. To address this issue, we herein predict virtual currency value fluctuations by collecting user opinion data from a virtual community and analyzing user sentiments or emotions from the opinion data. The proposed method is straightforward and applicable to predicting virtual currencies as well as to gaming environments, including MMORPGs. We test the proposed method using large-scale MMORPGs and demonstrate that virtual currencies can be effectively and efficiently predicted with it.

Adaptive space carving with texture mapping

Space carving reconstructs a 3D object from multiple images, but existing algorithms rely on a regular grid which makes poor use of memory. By using the image information, adaptive space carving uses a recursively generated structure which reduces memory requirements and thus allows a finer grid. After reconstruction, models are triangulated to facilitate texture mapping. Experimental results show the enhanced appearance of models reconstructed in this way.

Physics-inspired controllable flame animation

We propose a novel method conceptualized from the properties of physics where in particular the shape of a flame is determined by temperature that enables a control mechanism for the intuitive shaping of a flame. We focused on a trade-off issue from computer graphics whereby the turbulent flow that expresses the characteristics of the flame has a tendency to shift continuously, whereas the velocity constraints that contain a fluid within a target shape have a tendency to force movement in a particular direction. Trade-off made it difficult for animation designers to maintain a flame within the intended target shape. This paper resolves the issue by enabling the flame to be controlled without any velocity constraints by using the following two techniques: First, we model the temperature and force of the explosion generated by the combustion of explosive gaseous fuel and apply it to certain regions. Second, we expand the space of the interface between the fuel and the burned products, classifying that space into four regions and controlling the target shape of the flame by delicate adjustments to the temperature in each region. Experiments show that the flame maintains the appearance of dynamic movement while preserving the detailed 3D shapes specified by the scene designers.

Controlling liquids using pressure jump

This sketch presents a method to control liquids so that they flow into a target shape in a natural way. To avoid the oscillation and preserve the sharp detail of the target shape, we integrate the target-driven force into the projection step. So we require no post-optimization process for divergence-free condition at the liquid interface. Additionally, the target-driven force is calculated by enhanced ghost fluid method considering the pressure discontinuity around the liquid interface.

Efficiently detecting outlying behavior in video-game players

In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players’ characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse) was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.

Surface simplification with semantic features using texture and curvature maps

We propose a polygonal surface simplification algorithm that can preserve semantic features without user control. The semantic features of a model are important for human perception, which are insensitive to small geometric errors. Using an edge detects: Its three kinds of maps are employed to extract these features. First, an image map is generated boundary lines represent changes of chroma in the texture image by using edge detector. Second, the discrete curvatures at 3D vertices are mapped to the curvature map, and their data is also analyzed by an edge detector. Finally, a feature map is generated by combining the image and curvature maps. By finding areas of the 2D map that correspond to areas of the 3D model, semantic features can be preserved after simplification. We demonstrate this experimentally.

Physics-inspired approach to realistic and stable water spray with narrowband air particles

We propose an efficient and physics-inspired method for producing water spray effects by modeling air particles within a narrowband of the water surface in particle-based water simulation. In the real world, water and air continuously interact with each other around free surfaces, and this phenomenon is commonly observed in waterfalls or in rough sea waves. Due to the small volume of water spray, the interfaces between water and air become vague, and the interactions between water and air lead to strong vortex phenomena. To express these phenomena, we propose the generation of narrowband air cells in particle-based water simulations and the expression of water spray effects by creating and evolving air particles in narrowband air cells. We guarantee the robustness of the simulation by solving the drifting problem that occurs when the number of adjacent air particles is insufficient. Experiments convincingly demonstrate that the proposed approach is efficient and easy to use while delivering high-quality results. We produce efficient water spray effects from coarse simulation as an independent post-process that can be applied to most particle-based fluid solvers.

Efficient Representation of Detailed Foam Waves by Incorporating Projective Space

We propose an efficient framework to realistically simulate foam effects in which 3D water particles from a base water solver are first projected onto 2D screen space in order to reduce computational complexity of finding foam particles. Because foam effects are often created primarily in fast and complicated water flows, we analyze acceleration and curvature values to identify the areas exhibiting such flow patterns. Identified foam particles are emitted in 3D simulation space, and each foam particle is advected by its classified type based on its velocity, thereby capturing the essential characteristics of foam wave motions (e.g., floating waves or scattering bubbles). In addition, we provide an intuitive and flexible mechanism (e.g., user sketch or image) to customize parameters and control the appearance of foam effects while minimizing the occurrence of popping artifacts. Experiments convincingly demonstrate that the proposed approach is efficient and easy to use while delivering high-quality results.

Isoform Sequencing Provides a More Comprehensive View of the Panax ginseng Transcriptome

Korean ginseng (Panax ginseng C.A. Meyer) has been widely used for medicinal purposes and contains potent plant secondary metabolites, including ginsenosides. To obtain transcriptomic data that offers a more comprehensive view of functional genomics in P. ginseng, we generated genome-wide transcriptome data from four different P. ginseng tissues using PacBio isoform sequencing (Iso-Seq) technology. A total of 135,317 assembled transcripts were generated with an average length of 3.2 kb and high assembly completeness. Of those unigenes, 67.5% were predicted to be complete full-length (FL) open reading frames (ORFs) and exhibited a high gene annotation rate. Furthermore, we successfully identified unique full-length genes involved in triterpenoid saponin synthesis and plant hormonal signaling pathways, including auxin and cytokinin. Studies on the functional genomics of P. ginseng seedlings have confirmed the rapid upregulation of negative feed-back loops by auxin and cytokinin signaling cues. The conserved evolutionary mechanisms in the auxin and cytokinin canonical signaling pathways of P. ginseng are more complex than those in Arabidopsis thaliana. Our analysis also revealed a more detailed view of transcriptome-wide alternative isoforms for 88 genes. Finally, transposable elements (TEs) were also identified, suggesting transcriptional activity of TEs in P. ginseng. In conclusion, our results suggest that long-read, full-length or partial-unigene data with high-quality assemblies are invaluable resources as transcriptomic references in P. ginseng and can be used for comparative analyses in closely related medicinal plants.

Subtle features of ice with cloudy effects and scratches from collision damage

We propose a simulation framework for expressing cloudy effects and scratches on ice caused by the collision of other objects. Cloudy effects are created and diffused in proportion to the collision on the ice surfaces calculated by a combination of a grid‐projection technique and the boundary particle method. To prevent dissipation during the diffusion process, a geodesic distance is used as a constraint. Scratches are modeled directionally by analyzing the density gradient of cloudy effects and rendered using needle‐shaped ellipsoids. Experiments provide detailed expression of cloudy effects and scratches from collision damage. Copyright