• Title/Summary/Keyword: Ubiquitous System

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Review of Microbially Mediated Smectite-illite Reaction (생지화학적 스멕타이트-일라이트 반응에 관한 고찰)

  • Kim, Jin-Wook
    • Economic and Environmental Geology
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    • v.42 no.5
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    • pp.395-401
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    • 2009
  • The smectite-illite (SI) reaction is a ubiquitous process in siliciclastic sedimentary environments. For the last 4 decades the importance of smectite to illite (S-I) reaction was described in research papers and reports, as the degree of the (S-I) reaction, termed "smectite illitization", is linked to the exploration of hydrocarbons, and geochemical/petrophysical indicators. The S-I transformation has been thought that the reaction, explained either by layer-by-layer mechanism in the solid state or dissolution/reprecipitation process, was entirely abiotic and to require burial, heat, and time to proceed, however few studies have taken into account the bacterial activity. Recent laboratory studies showed evidence suggesting that the structural ferric iron (Fe(III)) in clay minerals can be reduced by microbial activity and the role of microorganisms is to link organic matter oxidation to metal reduction, resulting in the S-I transformation. In abiotic systems, elevated temperatures are typically used in laboratory experiments to accelerate the smectite to illite reaction in order to compensate for a long geological time in nature. However, in biotic systems, bacteria may catalyze the reaction and elevated temperature or prolonged time may not be necessary. Despite the important role of microbe in S-I reaction, factors that control the reaction mechanism are not clearly addressed yet. This paper, therefore, overviews the current status of microbially mediated smectite-to-illite reaction studies and characterization techniques.

Secure Mutual Authentication Protocol for RFID System without Online Back-End-Database (온라인 백-엔드-데이터베이스가 없는 안전한 RFID 상호 인증 프로토콜)

  • Won, Tae-Youn;Yu, Young-Jun;Chun, Ji-Young;Byun, Jin-Wook;Lee, Dong-Hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.20 no.1
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    • pp.63-72
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    • 2010
  • RFID is one of useful identification technology in ubiquitous environments which can be a replacement of bar code. RFID is basically consisted of tag, reader, which is for perception of the tag, and back-end-database for saving the information of tags. Although the usage of mobile readers in cellular phone or PDA increases, related studies are not enough to be secure for practical environments. There are many factors for using mobile leaders, instead of static leaders. In mobile reader environments, before constructing the secure protocol, we must consider these problems: 1) easy to lose the mobile reader 2) hard to keep the connection with back-end-database because of communication obstacle, the limitation of communication range, and so on. To find the solution against those problems, Han et al. suggest RFID mutual authentication protocol without back-end-database environment. However Han et al.'s protocol is able to be traced tag location by using eavesdropping, spoofing, and replay attack. Passive tag based on low cost is required lots of communication unsuitably. Hence, we analyze some vulnerabilities of Han et al.'s protocol and suggest RFID mutual authentication protocol without online back-end-database in aspect of efficiency and security.

A Study on the Operating Conditions of Lecture Contents in Contactless Online Classes for University Students (대학생 대상 비대면 온라인 수업에서의 강의 콘텐츠 운영 실태 연구)

  • Lee, Jongmoon
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.32 no.4
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    • pp.5-24
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    • 2021
  • The purpose of this study was to investigate and analyze the operating conditions of lecture contents in contactless online classes for University students. First, as a result of analyzing the responses of 93 respondents, 93.3% of the respondents took real-time online lectures (47.7%) or recorded video lectures (45.6%). Second, as a result of analyzing the contents used as textbooks, it was found that e-books (materials) and paper books (materials) were used together (36.6%), or e-books or electronic materials (36.6% and 37.6% respectively) were used in both liberal arts (47.3%) and major subjects (39.8%). In addition to textbooks, both major subjects and liberal arts highly used web materials (47.6% and 40.5% respectively) and YouTube materials (33.3% and 48.0% respectively) as external materials. Third, both liberal arts and major subjects used 'electronic files in the form of PPT or text organized and written by instructors' (62.9% and 58.1% respectively), 'internet materials' (16.7% and 19% respectively) and 'paper book or materials' (10.4% and 12.3% respectively) to share lecture contents. For the screen displayed lecture contents, 93.5% of the respondents satisfied in major subjects, and 90.2% of the respondents satisfied in liberal arts. These results suggest developing multimedia-based lecture contents and an evaluation solution capable of real-time exam supervision, developing a task management system capable of AI-based plagiarism search, task guidance, and task evaluation, and institutionalizing a solution to copyright problems for electronicizing lecture materials so that lectures can be given in the ubiquitous environment.

Recent Advances on TENG-based Soft Robot Applications (정전 발전 기반 소프트 로봇 응용 최신 기술)

  • Zhengbing, Ding;Dukhyun, Choi
    • Composites Research
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    • v.35 no.6
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    • pp.378-393
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    • 2022
  • As an emerging power generation technology, triboelectric nanogenerators (TENGs) have received increasing attention due to their boundless promise in energy harvesting and self-powered sensing applications. The recent rise of soft robotics has sparked widespread enthusiasm for developing flexible and soft sensors and actuators. TENGs have been regarded as promising power sources for driving actuators and self-powered sensors, providing a unique approach for the development of soft robots with soft sensors and actuators. In this review, TENG-based soft robots with different morphologies and different functions are introduced. Among them, the design of biomimetic soft robots that imitate the structure, surface morphology, material properties, and sensing/generating mechanisms of nature has greatly benefited in improving the performance of TENGs. In addition, various bionic soft robots have been well improved compared to previous driving methods due to the simple structure, self-powering characteristics, and tunable output of TENGs. Furthermore, we provide a comprehensive review of various studies within specific areas of TENG-enabled soft robotics applications. We first explore various recently developed TENG-based soft robots and a comparative analysis of various device structures, surface morphologies, and nature-inspired materials, and the resulting improvements in TENG performance. Various ubiquitous sensing principles and generation mechanisms used in nature and their analogous artificial TENG designs are demonstrated. Finally, biomimetic applications of TENG enabled in tactile displays as well as in wearable devices, artificial electronic skin and other devices are discussed. System designs, challenges and prospects of TENGs-based sensing and actuation devices in the practical application of soft robotics are analyzed.

A Study on the Implementation of Urban Senior Multi-Carezon for the Elderly (고령화에 따른 도시형 노인 시니어 멀티 케어존 실효성에 관한연구)

  • Lee, Jong-Sik
    • Journal of the Korea Knowledge Information Technology Society
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    • v.13 no.2
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    • pp.273-286
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    • 2018
  • Korean government has taken various population policy so far According to demographic results, The aging population is rapidly aging and it is expected to deepen in the future. However, many senior citizens are also exposed to poor economic conditions and inconsistent health care risks Most seniors suffer from mental illness and chronic diseases. seniors in traditional cities feel very alienated as they change from large family to small family. As the number of elderly people living alone grows, social problems increase. At present, the health care for the elderly who live alone is not being taken properly, and they are under a very poor management system, both physically and mentally. Every human being has to be old, and we aim to spend our old age processes physically and mentally healthy. As the basic age of the elderly increases, it is necessary to consider various aspects of the welfare policies and medical policies that are followed. In this study, 100 elderly people over the age of 65 were surveyed for economic situations and physical and mental health conditions, and specially performed study on utility of 'urban senior multi care zone' to prove the necessity of introducing the latest digital devices to resolve these problems more effectively by analyzing serious feelings of alienation, loneliness, and emotional situations. Lastly, We conducted this research to find ways to help the elderly through customized health care.

Changes of Autonomous Nerves Activities after the Gyorae Gotjawal Forest Bathing (곶자왈휴양림 삼림욕 후 자율신경 활성의 변화)

  • Sin, Bangsik;Lee, Keun Kwang
    • Journal of Naturopathy
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    • v.7 no.2
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    • pp.39-46
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    • 2018
  • Purpose: The purpose of this study was to evaluate the effect of the subjects after visiting the Gyorae forest on the activity of the autonomic nervous system. Methods: Before and after the forest bath, it was measured using a ubiquitous machine. Results: After the bath there was no significant difference in the sympathetic nerve activity (LF) of the control group, but the difference was significant in the experimental group by increasing (p<.038), and in the variance analysis, there was a significant difference between the groups (p<.014), between pre-and post-bath (p<.026), and also between the groups and pre-and post-bath (p<.018). The changes in parasympathetic activity (HF) were not significant in both the control and experimental. In the LF/HF ratio, the experimental group was significantly increased, and in the analysis of variance, there was also significant difference between group and before and after bath (p<.04). Mean pulse rate in the experimental group was a significant increase after bath (p<.026). In the change of pulse standard deviation, the value of the control and the experimental groups by variance analysis was a significant difference between the groups (p<.014). There was no difference between the mean values of the control and the experimental groups in the change of mean heart rate deviation. Conclusions: The autonomic nervous systems were activated after Gyorae forest bathing, where may be useful place for healing.

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Dynamic Decision Making using Social Context based on Ontology (상황 온톨로지를 이용한 동적 의사결정시스템)

  • Kim, Hyun-Woo;Sohn, M.-Ye;Lee, Hyun-Jung
    • Journal of Intelligence and Information Systems
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    • v.17 no.3
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    • pp.43-61
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    • 2011
  • In this research, we propose a dynamic decision making using social context based on ontology. Dynamic adaptation is adopted for the high qualified decision making, which is defined as creation of proper information using contexts depending on decision maker's state of affairs in ubiquitous computing environment. Thereby, the context for the dynamic adaptation is classified as a static, dynamic and social context. Static context contains personal explicit information like demographic data. Dynamic context like weather or traffic information is provided by external information service provider. Finally, social context implies much more implicit knowledge such as social relationship than the other two-type context, but it is not easy to extract any implied tacit knowledge as well as generalized rules from the information. So, it was not easy for the social context to apply into dynamic adaptation. In this light, we tried the social context into the dynamic adaptation to generate context-appropriate personalized information. It is necessary to build modeling methodology to adopt dynamic adaptation using the context. The proposed context modeling used ontology and cases which are best to represent tacit and unstructured knowledge such as social context. Case-based reasoning and constraint satisfaction problem is applied into the dynamic decision making system for the dynamic adaption. Case-based reasoning is used case to represent the context including social, dynamic and static and to extract personalized knowledge from the personalized case-base. Constraint satisfaction problem is used when the selected case through the case-based reasoning needs dynamic adaptation, since it is usual to adapt the selected case because context can be changed timely according to environment status. The case-base reasoning adopts problem context for effective representation of static, dynamic and social context, which use a case structure with index and solution and problem ontology of decision maker. The case is stored in case-base as a repository of a decision maker's personal experience and knowledge. The constraint satisfaction problem use solution ontology which is extracted from collective intelligence which is generalized from solutions of decision makers. The solution ontology is retrieved to find proper solution depending on the decision maker's context when it is necessary. At the same time, dynamic adaptation is applied to adapt the selected case using solution ontology. The decision making process is comprised of following steps. First, whenever the system aware new context, the system converses the context into problem context ontology with case structure. Any context is defined by a case with a formal knowledge representation structure. Thereby, social context as implicit knowledge is also represented a formal form like a case. In addition, for the context modeling, ontology is also adopted. Second, we select a proper case as a decision making solution from decision maker's personal case-base. We convince that the selected case should be the best case depending on context related to decision maker's current status as well as decision maker's requirements. However, it is possible to change the environment and context around the decision maker and it is necessary to adapt the selected case. Third, if the selected case is not available or the decision maker doesn't satisfy according to the newly arrived context, then constraint satisfaction problem and solution ontology is applied to derive new solution for the decision maker. The constraint satisfaction problem uses to the previously selected case to adopt and solution ontology. The verification of the proposed methodology is processed by searching a meeting place according to the decision maker's requirements and context, the extracted solution shows the satisfaction depending on meeting purpose.

An Empirical Study on the Influencing Factors of Perceived Job Performance in the Context of Enterprise Mobile Applications (업무성과에 영향을 주는 업무용 모바일 어플리케이션의 주요 요인에 관한 연구)

  • Chung, Sunghun;Kim, Kimin
    • Asia pacific journal of information systems
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    • v.24 no.1
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    • pp.31-50
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    • 2014
  • The ubiquitous accessibility of information through mobile devices has led to an increased mobility of workers from their fixed workplaces. Market researchers estimate that by 2016, 350 million workers will be using their smartphones for business purposes, and the use of smartphones will offer new business benefits. Enterprises are now adopting mobile technologies for numerous applications to increase their operational efficiency, improve their responsiveness and competitiveness, and cultivate their innovativeness. For these reasons, various organizational aspects concerning "mobile work" have received a great deal of recent attention. Moreover, many CIOs plan to allocate a considerable amount of their budgets mobile work environments. In particular, with the consumerization of information technology, enterprise mobile applications (EMA) have played a significant role in the explosive growth of mobile computing in the workplace, and even in improving sales for firms in this field. EMA can be defined as mobile technologies and role-based applications, as companies design them for specific roles and functions in organizations. Technically, EMA can be defined as business enterprise systems, including critical business functions that enable users to access enterprise systems via wireless mobile devices, such as smartphones or tablets. Specifically, EMA enables employees to have greater access to real-time information, and provides them with simple features and functionalities that are easy for them to complete specific tasks. While the impact of EMA on organizational workers' productivity has been given considerable attention in various literatures, relatively little research effort has been made to examine how EMA actually lead to users' job performance. In particular, we have a limited understanding of what the key antecedents are of such an EMA usage outcome. In this paper, we focus on employees' perceived job performance as the outcome of EMA use, which indicates the successful role of EMA with regard to employees' tasks. Thus, to develop a deeper understanding of the relationship among EMA, its environment, and employees' perceived job performance, we develop a comprehensive model that considers the perceived-fit between EMA and employees' tasks, satisfaction on EMA, and the organizational environment. With this model, we try to examine EMA to explain how job performance through EMA is revealed from both the task-technology fit for EMA and satisfaction on EMA, while also considering the antecedent factors for these constructs. The objectives of this study are to address the following research questions: (1) How can employees successfully manage EMA in order to enhance their perceived job performance? (2) What internal and/or external factors are important antecedents in increasing EMA users' satisfaction on MES and task-technology fit for EMA? (3) What are the impacts of organizational (e.g. organizational agility), and task-related antecedents (e.g., task mobility) on task-technology fit for EMA? (4) What are the impacts of internal (e.g., self-efficacy) and external antecedents (e.g., system reputation) for the habitual use of EMA? Based on a survey from 254 actual employees who use EMA in their workplace across industries, our results indicate that task-technology fit for EMA and satisfaction on EMA are positively associated with job performance. We also identify task mobility, organizational agility, and system accessibility that are found to be positively associated with task-technology fit for EMA. Further, we find that external factor, such as the reputation of EMA, and internal factor, such as self-efficacy for EMA that are found to be positively associated with the satisfaction of EMA. The present findings enable researchers and practitioners to understand the role of EMA, which facilitates organizational workers' efficient work processes, as well as the importance of task-technology fit for EMA. Our model provides a new set of antecedents and consequence variables for a TAM involving mobile applications. The research model also provides empirical evidence that EMA are important mobile services that positively influence individuals' performance. Our findings suggest that perceived organizational agility and task mobility do have a significant influence on task-technology fit for EMA usage through positive beliefs about EMA, that self-efficacy and system reputation can also influence individuals' satisfaction on EMA, and that these factors are important contingent factors for the impact of system satisfaction and perceived job performance. Our findings can help managers gauge the impact of EMA in terms of its contribution to job performance. Our results provide an explanation as to why many firms have recently adopted EMA for efficient business processes and productivity support. Our findings additionally suggest that the cognitive fit between task and technology can be an important requirement for the productivity support of EMA. Further, our study findings can help managers in formulating their strategies and building organizational culture that can affect employees perceived job performance. Managers, thus, can tailor their dependence on EMA as high or low, depending on their task's characteristics, to maximize the job performance in the workplace. Overall, this study strengthens our knowledge regarding the impact of mobile applications in organizational contexts, technology acceptance and the role of task characteristics. To conclude, we hope that our research inspires future studies exploring digital productivity in the workplace and/or taking the role of EMA into account for employee job performance.

An Exploratory study on the Direction of Home Economics Education associated with the future social change: focusing on the new recognition of the characteristic as the Subjects for Life and Happiness (미래 사회의 변화와 가정과교육의 방향 탐색 - '삶 중심 교과'와 '행복 교과'로서의 성격 재인식을 중심으로 -)

  • Wang, Seok-Soon
    • Journal of Korean Home Economics Education Association
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    • v.28 no.3
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    • pp.17-32
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    • 2016
  • This exploratory study which applied environmental scanning method to analyse a change in a future society tried to diagnose a reaction ability of our education system for the change in the future society. In addition, the study tried to explore an adequate direction for Home Economics Subject to be an mandatory subject continuously toward the change in the future society. Main changes in the future society can be expected as 1) demographic change due to low birth rate and aging society, 2) an increasing threat of a human living environment due to unexpectable natural disasters and accidents, 3) a radical progress into a ubiquitous computing environment led by AI, 4) an advent of a borderless economic society and a change for jobs, 5) a change in North Korea, and so on. Our education system which mostly concentrates on education to develop constructive intelligence by halving the society and schooling as yet, however, is diagnosed as it has a paradox that can not understand an emotional competency as a target for studying. Home Economics Subject is worth as the subject that can exactly complement a blind spot of our education system which can not respond to the future society adequately. This is because Home Economics Subject has had a characteristic as a 'Subject of Life' traditionally that has dealt with an overall 'life' of human beings, and the characteristic is favorable to develop human practical intelligence. Thus, because the 'life' is the main point of Home Economics Subject, it has the characteristic as a 'Subject of Happiness' which is the most effective method to develop a tendency to appreciate, a sense of empathy, and lots of pro-social behaviors that are important capacities to seek for happiness. As Alderfer's ERG Theory is to understand human beings' behavior based on the satisfactory of human beings' hierarchical desires, it is suggested as an adequate frame for the theory to restructure the characteristic of Home Economics Subject which develops the 'capacity to seek for happiness' by focusing the 'life', into core concept and core capacity of curriculum. A follow-up study should make a connection between ERG Theory and core concept and core capacity of curriculum to explore how the theory can be reflected on Home Economics curriculum.

Context Prediction Using Right and Wrong Patterns to Improve Sequential Matching Performance for More Accurate Dynamic Context-Aware Recommendation (보다 정확한 동적 상황인식 추천을 위해 정확 및 오류 패턴을 활용하여 순차적 매칭 성능이 개선된 상황 예측 방법)

  • Kwon, Oh-Byung
    • Asia pacific journal of information systems
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    • v.19 no.3
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    • pp.51-67
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    • 2009
  • Developing an agile recommender system for nomadic users has been regarded as a promising application in mobile and ubiquitous settings. To increase the quality of personalized recommendation in terms of accuracy and elapsed time, estimating future context of the user in a correct way is highly crucial. Traditionally, time series analysis and Makovian process have been adopted for such forecasting. However, these methods are not adequate in predicting context data, only because most of context data are represented as nominal scale. To resolve these limitations, the alignment-prediction algorithm has been suggested for context prediction, especially for future context from the low-level context. Recently, an ontological approach has been proposed for guided context prediction without context history. However, due to variety of context information, acquiring sufficient context prediction knowledge a priori is not easy in most of service domains. Hence, the purpose of this paper is to propose a novel context prediction methodology, which does not require a priori knowledge, and to increase accuracy and decrease elapsed time for service response. To do so, we have newly developed pattern-based context prediction approach. First of ail, a set of individual rules is derived from each context attribute using context history. Then a pattern consisted of results from reasoning individual rules, is developed for pattern learning. If at least one context property matches, say R, then regard the pattern as right. If the pattern is new, add right pattern, set the value of mismatched properties = 0, freq = 1 and w(R, 1). Otherwise, increase the frequency of the matched right pattern by 1 and then set w(R,freq). After finishing training, if the frequency is greater than a threshold value, then save the right pattern in knowledge base. On the other hand, if at least one context property matches, say W, then regard the pattern as wrong. If the pattern is new, modify the result into wrong answer, add right pattern, and set frequency to 1 and w(W, 1). Or, increase the matched wrong pattern's frequency by 1 and then set w(W, freq). After finishing training, if the frequency value is greater than a threshold level, then save the wrong pattern on the knowledge basis. Then, context prediction is performed with combinatorial rules as follows: first, identify current context. Second, find matched patterns from right patterns. If there is no pattern matched, then find a matching pattern from wrong patterns. If a matching pattern is not found, then choose one context property whose predictability is higher than that of any other properties. To show the feasibility of the methodology proposed in this paper, we collected actual context history from the travelers who had visited the largest amusement park in Korea. As a result, 400 context records were collected in 2009. Then we randomly selected 70% of the records as training data. The rest were selected as testing data. To examine the performance of the methodology, prediction accuracy and elapsed time were chosen as measures. We compared the performance with case-based reasoning and voting methods. Through a simulation test, we conclude that our methodology is clearly better than CBR and voting methods in terms of accuracy and elapsed time. This shows that the methodology is relatively valid and scalable. As a second round of the experiment, we compared a full model to a partial model. A full model indicates that right and wrong patterns are used for reasoning the future context. On the other hand, a partial model means that the reasoning is performed only with right patterns, which is generally adopted in the legacy alignment-prediction method. It turned out that a full model is better than a partial model in terms of the accuracy while partial model is better when considering elapsed time. As a last experiment, we took into our consideration potential privacy problems that might arise among the users. To mediate such concern, we excluded such context properties as date of tour and user profiles such as gender and age. The outcome shows that preserving privacy is endurable. Contributions of this paper are as follows: First, academically, we have improved sequential matching methods to predict accuracy and service time by considering individual rules of each context property and learning from wrong patterns. Second, the proposed method is found to be quite effective for privacy preserving applications, which are frequently required by B2C context-aware services; the privacy preserving system applying the proposed method successfully can also decrease elapsed time. Hence, the method is very practical in establishing privacy preserving context-aware services. Our future research issues taking into account some limitations in this paper can be summarized as follows. First, user acceptance or usability will be tested with actual users in order to prove the value of the prototype system. Second, we will apply the proposed method to more general application domains as this paper focused on tourism in amusement park.