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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korea Society of Computer and Information
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Korean Society of Computer Information
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Volume & Issues
Volume 16, Issue 12 - Dec 2011
Volume 16, Issue 11 - Nov 2011
Volume 16, Issue 10 - Oct 2011
Volume 16, Issue 9 - Sep 2011
Volume 16, Issue 8 - Aug 2011
Volume 16, Issue 7 - Jul 2011
Volume 16, Issue 6 - Jun 2011
Volume 16, Issue 5 - May 2011
Volume 16, Issue 4 - Apr 2011
Volume 16, Issue 3 - Mar 2011
Volume 16, Issue 2 - Feb 2011
Volume 16, Issue 1 - Jan 2011
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The buffer Management system for reducing write/erase operations in NAND flash memory
Jung, Bo-Sung ; Lee, Jung-Hoon ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 1~10
DOI : 10.9708/jksci.2011.16.10.001
There are the large overhead of block erase and page write operations in NAND flash memory, though it has low power consumption, cheap prices and a large storage. Due to the physical characteristics of NAND flash memory, overwrite operations are not permitted at the same location, so rewriting operation require after erase operation. it cause performance decrease of NAND flash memory. Using SRAM buffer in traditional NAND flash memory, it can not only reduce effective write operation but also guarantee fast memory access time. In this paper, we proposed the small SRAM buffer management system for reducing overhead of NAND flash memory, that is, erase and write operations. The proposed buffer system in a NAND flash memory consists of two parts, i.e., a fully associative temporal buffer with the small fetching block size and a fully associative spatial buffer with the large fetching block size. The temporal buffer have small fetching blocks that referenced from spatial buffer. When it happen write operations or erase operations in NAND flash memory, the related fetching blocks in temporal buffer include a page or a block are written in NAND flash memory at the same time. The writing and erasing counts in NAND flash memory can be reduced. According to the simulation results, although we have high miss ratios, write and erase operations can be reduced approximatively 58% and 83% respectively. Also the average memory access times are improved about 84% compared with the fully associative buffer with two sizes.
Performance Evaluation and Verification of MMX-type Instructions on an Embedded Parallel Processor
Jung, Yong-Bum ; Kim, Yong-Min ; Kim, Cheol-Hong ; Kim, Jong-Myon ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 11~21
DOI : 10.9708/jksci.2011.16.10.011
This paper introduces an SIMD(Single Instruction Multiple Data) based parallel processor that efficiently processes massive data inherent in multimedia. In addition, this paper implements MMX(MultiMedia eXtension)-type instructions on the data parallel processor and evaluates and analyzes the performance of the MMX-type instructions. The reference data parallel processor consists of 16 processors each of which has a 32-bit datapath. Experimental results for a JPEG compression application with a 1280x1024 pixel image indicate that MMX-type instructions achieves a 50% performance improvement over the baseline instructions on the same data parallel architecture. In addition, MMX-type instructions achieves 100% and 51% improvements over the baseline instructions in energy efficiency and area efficiency, respectively. These results demonstrate that multimedia specific instructions including MMX-type have potentials for widely used many-core GPU(Graphics Processing Unit) and any types of parallel processors.
I/O Scheme of Hybrid Hard Disk Drive for Low Power Consumption and Effective Response Time
Kim, Jeong-Won ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 23~31
DOI : 10.9708/jksci.2011.16.10.023
Recently, Solid state disk is mainly used because this device has lower power consumption as well as higher response time. But it features higher price and lower performance at delete and write operations compared with HDD. To compensate this defect, Hybrid hard disk with internal non-volatile flash memory was issued. This NVCache is used as a kind of cache for disk blocks. In this paper, an I/O scheme for H-HDD is proposed for improving low power consumption as well as response time. Our method is to use this NVCache as read cache mainly and write cache when write requests are concentrated. In read cache operation, disk blocks with higher priority determined on basis of time as well as spatial localities are prefetched, which can improve response time. The write operation is conducted only at write peak time as disk spindle up costs higher battery power as well as response time. Experiments results show that the suggested method can improve response time of H-HDD and lower the power consumption.
Effective indexing of moving objects for current position management in Road Networks
Kim, Tae-Gyu ; Shin, Soong-Sun ; Chung, Weo-Nil ; Bae, Hae-Young ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 33~43
DOI : 10.9708/jksci.2011.16.10.033
Recently, advances in mobile communication and location identifying technology of the moving object is evolving. Therefore, the location-based services based on request for service have increased and a variety of the indexing for the position management of moving objects has been studied. Because the index based on Euclidean space are no restriction of movement, it is difficult to apply to the real world. Also, there is additional cost to find adjacent road segments in road networks-based indexing. Existing studies of fixed static objects such as buildings or hospitals are not considered. In this paper, we propose an efficient road networks-based indexing for management of current positions. The proposed indexing partitions road networks by grids and has integrated road connection informations and manage separated extra indexing for fixed static objects. Through the experiment, we show that the proposed indexing based on road networks improves the performance of operation for search or update than existing indexing.
Development of a Teaching and Learning Model for Educational Usage of Web 2.0 and Its Effect Analysis
Kim, Hae-Jung ; Choi, Jae-Hyuk ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 45~52
DOI : 10.9708/jksci.2011.16.10.045
Web 2.0 could influence the teaching and learning system significantly due to its characteristics to utilize information using internet in various ways, to create information, and to reorganize it through information sharing. In this new environment of information-oriented classes using the computer, positive education method is required to develop new teaching/learning method based on the internet web 2.0 in order to fulfill the learner`s intellectual curiosity and to lead the future-oriented classes. This paper proposed a teaching-learning models in the web 2.0-based internet information education and its effect analysis.
Object Recognition Face Detection With 3D Imaging Parameters A Research on Measurement Technology
Choi, Byung-Kwan ; Moon, Nam-Mee ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 53~62
DOI : 10.9708/jksci.2011.16.10.053
In this paper, high-tech IT Convergence, to the development of complex technology, special technology, video object recognition technology was considered only as a smart - phone technology with the development of personal portable terminal has been developed crossroads. Technology-based detection of 3D face recognition technology that recognizes objects detected through the intelligent video recognition technology has been evolving technologies based on image recognition, face detection technology with through the development speed is booming. In this paper, based on human face recognition technology to detect the object recognition image processing technology is applied through the face recognition technology applied to the IP camera is the party of the mouth, and allowed the ability to identify and apply the human face recognition, measurement techniques applied research is suggested. Study plan: 1) face model based face tracking technology was developed and applied 2) algorithm developed by PC-based measurement of human perception through the CPU load in the face value of their basic parameters can be tracked, and 3) bilateral distance and the angle of gaze can be tracked in real time, proved effective.
Recognition of Handwritten Digits Based on Neural Network and Fuzzy Inference
Ko, Chang-Ryong ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 63~71
DOI : 10.9708/jksci.2011.16.10.063
We present a method to modify the recognition of neural networks by the fuzzy inference in a handwritten digit recognition with large deformations, and we verified the method by the experiment. The neural networks take long time in learning and recognize 100% on the learning pattern. But the neural networks don`t show a good recognition on the testing pattern. So, we apply the modified method as the fuzzy inference. As a result, the recognition and false recognition of neural networks was improved 90.2% and 9.8% respectively at 89.6% and 10.4% initially. This approach decreased especially the false recognition on digit 3, 5. We used the density of digit to extract the fuzzy membership function in this experiment. But, because the handwritten digit have varified input patterns, we will get a better recognition by extracting varifed characteristics and applying the composite fuzzy inference. We also propose the application of fuzzy inference on matching the input pattern, than applying strictly the fuzzy inference.
A Proposal for Improving Techniques of GTS Utilization Based on WBAN
Park, Joo-Hee ; Jung, Won-Soo ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 73~81
DOI : 10.9708/jksci.2011.16.10.073
The WBAN(Wireless Body Area Network) technology is a short distance wireless network which provides each device`s interactive communication by connecting devices inside and outside of body located within 3 meters. Standardization on the physical layer, data link layer, network layer and application layer is in progress by IEEE 802.15.6 TG BAN. The The WBAN servides consists of both medical and non-medical applications. The medical application service uses the sensor that transfer the periodic traffic and have different data rates. It uses GTS method to guarantee QoS. In this paper, a new method is proposed, which are suitable design for MAC Protocol. Firstly, MAC frame structure and a primitive based on the WBAN are proposed. Secondly, we proposed the GTS algorithm improved the channel utilization based on the WFQ(Weighted Fair Queuing). The proposed scheduling method is improved channel utilization compared with i-Game(Round Robin scheduling method).
Study on evaluating the significance of 3D nuclear texture features for diagnosis of cervical cancer
Choi, Hyun-Ju ; Kim, Tae-Yun ; Malm, Patrik ; Bengtsson, Ewert ; Choi, Heung-Kook ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 83~92
DOI : 10.9708/jksci.2011.16.10.083
The aim of this study is to evaluate whether 3D nuclear chromatin texture features are significant in recognizing the progression of cervical cancer. In particular, we assessed that our method could detect subtle differences in the chromatin pattern of seemingly normal cells on specimens with malignancy. We extracted nuclear texture features based on 3D GLCM(Gray Level Co occurrence Matrix) and 3D Wavelet transform from 100 cell volume data for each group (Normal, LSIL and HSIL). To evaluate the feasibility of 3D chromatin texture analysis, we compared the correct classification rate for each of the classifiers using them. In addition to this, we compared the correct classification rates for the classifiers using the proposed 3D nuclear texture features and the 2D nuclear texture features which were extracted in the same way. The results showed that the classifier using the 3D nuclear texture features provided better results. This means our method could improve the accuracy and reproducibility of quantification of cervical cell.
Face and Its Components Extraction of Animation Characters Based on Dominant Colors
Jang, Seok-Woo ; Shin, Hyun-Min ; Kim, Gye-Young ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 93~100
DOI : 10.9708/jksci.2011.16.10.093
The necessity of research on extracting information of face and facial components in animation characters have been increasing since they can effectively express the emotion and personality of characters. In this paper, we introduce a method to extract face and facial components of animation characters by defining a mesh model adequate for characters and by using dominant colors. The suggested algorithm first generates a mesh model for animation characters, and extracts dominant colors for face and facial components by adapting the mesh model to the face of a model character. Then, using the dominant colors, we extract candidate areas of the face and facial components from input images and verify if the extracted areas are real face or facial components by means of color similarity measure. The experimental results show that our method can reliably detect face and facial components of animation characters.
The Prime Counting Function
Lee, Sang-Un ; Choi, Myeong-Bok ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 101~109
DOI : 10.9708/jksci.2011.16.10.101
The Riemann`s zeta function
has been known as answer for a number of primes
(x) less than given number x. In prime number theorem, there are another approximation function
,Li(x), and R(x). The error about
(x) is R(x) < Li(x) <
. The logarithmic integral function is Li(x)
Result Analysis of Training Programs for Stengthening Teacher`s ICT Competency
Suh, Soon-Shik ; Kim, Sung-Wan ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 111~120
DOI : 10.9708/jksci.2011.16.10.111
The purpose of this study is to analyze the results of training programs for strengthening teachers` ICT competency and to suggest the ways to improve the existing ones. To do this, we conducted literature review, web survey with teachers, and in-depth interview with training program operators. The results of the online survey indicated that generally speaking, the programs had been operated desirably, although three programs(Thinking with Technology Course, Essential Course, e-PBL Instructional Design Course) needed to take additional efforts for their effectiveness and efficiency. According to the results of in-depth interview with training operators, they demanded re-training for lecturers, self career development, quality control of regional delivery training, expansion of training periods, and post-supports after training etc.
An Approach of False Data Identification Protocol for Minimum Communication Cost in Wireless Sensor Network
Boonsongsrikul, Anuparp ; Park, Seung-Kyu ; Shin, Seung-Hun ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 121~129
DOI : 10.9708/jksci.2011.16.10.121
In wireless sensor networks, a compromised sensor node can inject false data during data aggregation. Existing solutions of securing data aggregation require high communication cost in securing data aggregation. In this paper, we propose a monitoring-based secure data aggregation protocol that minimizes communication cost of identifying the location of false data injection attacks. The main idea is that when monitoring nodes find an injected false data, their reporting messages along with Message Authentication Codes (MACs) are summarized in a single message before sending it to the Base Station (BS). Then the BS identifies the attacking node. The simulation shows that energy consumption of the proposed protocol with short and normal concatenations of MACs are 45% and 36% lower than that of an existing protocol, respectively.
The Design and fabrication of Multi Channel Receiver for Radar System
Lee, Ki-Hong ; Kim, Wan-Sik ; Kim, Gye-Kuk ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 131~136
DOI : 10.9708/jksci.2011.16.10.131
In this paper, we fabricate multi channel receiver for radar system. This receiver at X-band can be received 8 signal of an identical characteristic, dynamic range has more than 80[dB]. To process direct received signals, this system has the built-in two digital de-modulators which offer the minimum loss on the receiving signal path and has high stability by adding Built-In Test. The gain, noise figure, difference of amplitude and phase on the signal path is respectively 20
Power Spectrum Performance Analysis of Digital M/W Transmission System in Non-Selective Rayleigh Fading Channel
Park, Ki-Sik ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 137~145
DOI : 10.9708/jksci.2011.16.10.137
In this paper, we modeled digital M/W transmission channel by frequency non-selective fading channel and analyzed the power spectrum magnitude of digital M/W transmission systems adopting OFDM modulation scheme through simulation. From the simulation results, it was found that deep does not appear in the specified fixed bandwidth under the AWGN environment. Also, lower power spectrum magnitude was shown in frequency non-selective fading channel than that in AWGN channel. Futhermore, the power spectrum magnitude value became more lowered when carrier frequency and vehicle speed became higher.
An Efficient Video Management Technique using Forward Timeline on Multimedia Local Server
Lee, Jun-Pyo ; Woo, Soon ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 147~153
DOI : 10.9708/jksci.2011.16.10.147
In this paper, we present a new video management technique using forward timeline to efficiently store and delete the videos on a local server. The proposed method is based on capturing the changing preference of the videos according to recentness, frequency, and playback length of the requested videos. For this purpose, we utilize the forward timeline which represents the time area within a number of predefined intervals. The local server periodically measures time popularity and request segment of all videos. Based on the measured data, time popularity and request segment, the local server calculates the mean time popularity and mean request segment of a video using forward timeline. Using mean time popularity and mean request segment of video, we estimate the ranking and allocated storage space of a video. The ranking represents the priority of deletion when the storage area of local server is running out of space and the allocated storage space means the maximum size of storage space to be allocated to a video. In addition, we propose an efficient storage space partitioning technique in order to stably store videos and present a time based free-up storage space technique using the expected variation of video data in order for avoiding the overflow on a local server in advance. The simulation results show that the proposed method performs better than other methods in terms of hit rate and number of deletion. Therefore, our video management technique for local server provides the lowest user start-up latency and the highest bandwidth saving significantly.
Suggestion of New Educational Model with Smart Phone & QR Code: Integration of Mobile Device, QR Code and the Book-Type Textbooks
Park, Jae-Hyun ; Park, Durk-Won ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 155~164
DOI : 10.9708/jksci.2011.16.10.155
As Information & Communication Technology is developed in fast speed, the educational field undertakes many changes in utilizing Information Technology(IT). As the smart phone`s educational utilization brings many positive effects, so many people are interested in such educational application programs. The e-textbooks or learning contents based on the web have shown some limits in being utilized as main learning materials in school field. So this study identified such limits, and suggested a new direction for professional education by integrating mobile and QR code technologies with existing textbooks to realize a new book-type E-Textbook model. And this study purposed for students to participate in their classes more easily through making open-education environment for students studying specialized subjects and by applying new teaching-learning methods inducing more interest in them. Of course, this study`s ultimate purpose is to raise students` learning ability about specialized subjects, and further, to improve their self-directed learning abilities with increased interests in classes. As the result operating this model, it was found that this model had enough learning effect.
An Energy-aware Dynamic Source Routing Algorithm for Mobile Ad-hoc Networks
Lee, Cheong-Yeop ; Shin, Yong-Hyeon ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 165~173
DOI : 10.9708/jksci.2011.16.10.165
In Mobile Ad-hoc Network(MANET), mobile nodes are operated by limited batteries. Therefore, it is very important to consume the battery power efficiently to prevent termination of the network. In this paper, we propose Energy-aware Dynamic Source Routing(EDSR) which is based on the Dynamic Source Routing(DSR) to increase the packet transmission and lifetime of the network. If the battery power of a node reaches threshold level, then the node gives up the function of relaying to save battery power except as a source and a destination node. While the conventional DSR doesn`t consider the battery consumptions of the nodes, EDSR blocks the nodes from relaying whose battery powers are below the threshold level. Simulation results show the proposed EDSR is more efficient in packet transmission and network lifetime through the balanced battery consumption of the mobile nodes.
Invisible Watermarking for Improved Security of Digital Video Application
Seo, Jung-Hee ; Park, Hung-Bog ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 175~183
DOI : 10.9708/jksci.2011.16.10.175
Performance of digital video watermarking is an assessment that hides a lot of information in digital videos. Therefore, it is required to find a way that enables to store lots of bits of data into a high quality video of the frequency area of digital contents. Hence, this paper designs a watermarking system improving security with an enhancing watermarking based on invisible watermarking and embedding an watermarking on LH and HL subband and its subband by transforming wavelet after the extraction of luminance component from the frames of video by compromising robustness and invisible of watermarking elements. The performance analysis of security of watermarking is carried out with a statistic method, and makes an assessment of robustness against variety of attacks to invisible watermarking. We can verify the security of watermarking against variety of attacks by testing robustness and invisible through carrying out general signal processing like noise addition, lossy compression, and Low-Pass filtering.
Smart Exercise Prescription of Elderly Users using Visual Path Map
Jeong, Chan-Soon ; Ham, Jun-Seok ; Ko, Il-Ju ; Hur, Jun-Soo ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 185~196
DOI : 10.9708/jksci.2011.16.10.185
Exercise programs for elderly users are operated by each department and facility, but it is not enough to visualize exercise prescription and effect followed by elderly users physical conditions. The purpose of this study is to suggest exercise prescription for elderly users with a visual path map. A visual path map is to visually present types of users classified according to physical strength conditions, the process of exercise prescription, and effects of exercise. Exercise prescription is divided into four stages: analysis of physical conditions, exercise prescription by the visual path map, smart exercise prescription, and exercise for elderly users. The first stage, analysis of physical conditions is to classify physical conditions by each type by mechanically learning elderly users` physical test values. The second stage, exercise prescription by the visual path map, is to present exercise prescription suitable for elderly users` physical conditions. The third stage, smart exercise prescription, is to offer exercise prescription of the day when exercise is carried out using elderly users` smart phones in consideration of their situations. The fourth stage, exercise for elderly users, is to provide information by their smart phones when they exercise. In conclusion, this study will be able to induce elderly users to do continuous exercise by motivating them.
A Energy-Efficient Cluster Header Election Algorithm in Ubiquitous Sensor Networks
Hur, Tai-Sung ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 197~203
DOI : 10.9708/jksci.2011.16.10.197
In this paper, a new cluster configuration process is proposed. The energy consumption of sensor nodes is reduced by configuring the initial setup process only once with keeping the initial cluster. Selecting the highest power consumed node of the member nodes within the cluster to the header of next round can distribute power consumption of all nodes in the cluster evenly. With this proposed way, the lifetime of the USN is increased by the reduced energy consumption of all nodes in the cluster. Also, evenly distributed power consumptions of sensors are designed to improve the energy hole problem. The effectiveness of the proposed algorithms is confirmed through simulations.
SNS-based Site connected with shopping Using Avatar
Ha, Yan ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 205~210
DOI : 10.9708/jksci.2011.16.10.205
This paper is implemented new styled site to combine community of blog style for SNS and shopping mall. Especially, this site is included simulation of coordination in fashion with avatar model. It makes indirect experience of clothing and user-friendly user interface that is different to other Web sites or shopping malls. So this avatar is designed and implemented by using flash animation technique that makes confirm possible coordination styles with eyes of client instantly and review goods very easily. Additionally, it makes pay attention to connect shopping malls and service convenience by SNS.
A Study on the Organizational Learning of the Disaster Management Organizations: the Cases of Daegu Subway
Kim, Jong-Hwan ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 211~218
DOI : 10.9708/jksci.2011.16.10.211
Although the disaster management of Korea such as mitigation of disasters, preparedness for them and recovery from them. It should be considered based on the failures of the disaster management and the past experimental knowledge, it is believed that the repetitive occurrence of similar disasters is caused by absence of learning of disaster management organizational. That is, non-learning of the management organs due to experimental errors indicates that the organization themselves are not able to adjust to environment and the same kinds of disasters may happen in the future. Therefore, this study identifies repetitive failures by analysing reasons of the failures in terms of organizational learning in order to prevent from repetition of similar failures, and presents suggestions on the policy of disaster management. For the purposes, it carries both bibliographical analysis and case analysis. this study targets Daegu Subway Fire in 2003.
A Reconsideration on the Efficiency of the Extended Projection Principle
Joo, Chi-Woon ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 219~228
DOI : 10.9708/jksci.2011.16.10.219
Main concern will be put at suggesting an alternative idea about the basic notion of the Extended Projection Principle (henceforth, ECP) which has been slightly changed since the initial appearance of the EPP. The EPP had been dependent on Case and theta-role under the era of the early generative grammar, whereas it was reduced only to the categorial feature [D] under the minimalism. Various data such as Locative Inversion constructions, there-expletive constructions, and sentences related to binding theory will be dealt with to suggest an plausible alternative idea. As a conclusion, it will be attested that the SPEC position of the inflectional clause should be filled with a maximally projected lexical item. This conclusion will be reached by analyzing lots of linguistic data.
A Multiple Regression Analysis on Developing the Profitability Model of Local Cultural Festivals
Choi, Rack-In ;
Journal of the Korea Society of Computer and Information, volume 16, issue 10, 2011, Pages 229~239
DOI : 10.9708/jksci.2011.16.10.229
This study aims to suggest profitability models of local cultural festival to be a focal point of local culture to overcome the abuses as an annual event led by the local government agencies have been in force in every local areas currently, to elicit the local residents` voluntary participation and to engage the outside tourists in connection of a more effective promotion and marketing. The festival is attractive to people with that provoke mirth and inspire curiosity, but the festival is not a one-time event ongoing maintenance enlarge: It is absolutely necessary in order to effort to reach at consumer-oriented quality of service. Also this research intends to present a activation scheme by developing profitability models to make profits while holding a number of risks taking into account the characteristics of the local festival service carried out. To this end, based on established research, leading indicator and expert opinion were analyzed through multiple regression analysis.