• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.9
• /
• pp.916-920
• /
• 2008

The personal workspace consists of user- specified computing environment such as user profile, applications and their configurations, and user data. Mobile computing devices (i.e., cellular phones, PDAs, laptop computers, and Ultra Mobile PC) are getting smaller and lighter to provide personal work-space ubiquitously. However, various personal work-space mobility solutions (c.f. VMWare Pocket ACE[1], Mojopac[2], u-PC[3], etc.) are appeared with the advance of virtualization technology and portable storage technology. The personal workspace can be loaded at public PC using above solutions. Especially, we proposed a framework called ubiquitous personal computing environment (u-PC) that supports mobility of personal workspace based on wireless iSCSI network storage in our previous work. However, previous u-PC could support limited applications, because it uses IRP (I/O Request Packet) forwarding technique at filter driver level on Windows operating system. In this paper, we implement OS-level virtualization technology using system call hooking on Windows operating system. It supports personal workspace mobility and covers previous u-PC limitation. Also, it overcomes personal workspace loading overhead that is limitation of other solutions (i.e., VMWare Pocket ACE, Mojopac, etc). We implement a prototype consisting of Windows XP-based host PC and Linux-based mobile device connected via WiNET protocol of UWB. We leverage several use~case models of our framework for proving its usability.

• The Journal of Industrial Distribution & Business
• /
• v.9 no.12
• /
• pp.45-53
• /
• 2018

Purpose - The purpose of the study was to investigate operation system of current convenience store and competing retail store and to find out development of unattended convenience store. Operators can save labor cost and solve labor seeking when opening shop under suitable environment and commerce area, and assure of employee's safety. Customers are allowed to select commodity comfortably without disclosure of face and to shorten standby time at simple store opening, buying and paying and to produce convenient living environment by financing, delivery and goods control. This study examined effect and problems of operation of existing and unattended convenience store from point of view of visual merchandising to find out model of unattended convenience store and to strengthen competitiveness of convenience store business. Research design, data, and methodology - Research procedure of accomplishment of goal of the study was: The study investigated state of distribution business, and role and definition of VMD. First, VMD played an important role of promotion and competitiveness of unattended convenience stores. Second, the author investigated research and cases of unattended convenience stores 14 months, that is to say, from August 15, 2017 to October 15, 2018. Third, the author investigated on-the-spot three of common convenience stores, three of unattended convenience stores and three of retailers one month, that is to say, June 1, 2018 to July 1, 2018. The subject was convenience stores and retailers selling similar type of products at Seoul and metropolitan area. Results - Layout, selling place, brand identity, goods assortment, authentication system, product information cognition and control, buying and payment system, security system, salesmen, promotion and other services should be improved from point of view of merchandising. Structure, furniture, lighting, voice, façade, VP, PP, IP and POP should be developed. Conclusions - Unattended convenience stores saved operating cost and lessened labor and gave visitors convenience and comfortable shopping and made use of resources effectively. Further studies with quantitative analysis shall find out strategic conditions for promotion of unattended convenience stores.

• The KIPS Transactions:PartC
• /
• v.18C no.5
• /
• pp.303-316
• /
• 2011

Data aggregation is important in wireless sensor networks. However, it also introduces many security problems, one of which is that a compromised node may inject false data or drop a message during data aggregation. Most existing solutions rely on encryption, which however requires high computation and communication cost. But they can only detect the occurrence of an attack without finding the attacking node. This makes sensor nodes waste their energy in sending false data if attacks occur repeatedly. Even an existing work can identify the location of a false data injection attack but it has a limitation that at most 50% of total sensor nodes can participate in data transmission. Therefore, a novel approach is required such that it can identify an attacker and also increase the number of nodes which participate in data transmission. In this paper, we propose a monitoring-based secure data aggregation protocol to prevent against a compromised aggregator which injects false data or drops a message. The proposed protocol consists of aggregation tree construction and secure data aggregation. In secure data aggregation, we use integration of abnormal data detection with monitoring and a minimal cryptographic technique. The simulation results show the proposed protocol increases the number of participating nodes in data transmission to 95% of the total nodes. The proposed protocol also can identify the location of a compromised node which injects false data or drops a message. A communication overhead for tracing back a location of a compromised node is O(n) where n is the total number of nodes and the cost is the same or better than other existing solutions.

• The KIPS Transactions:PartC
• /
• v.15C no.3
• /
• pp.157-166
• /
• 2008

The ubiquitous service environment is poor in reliability of connection and also has a high probability that the intrusion against a system and the failure of the services may happen. Therefore, It is very important to guarantee that the legitimate users make use of trustable services from the viewpoint of security without discontinuance or obstacle of the services. In this paper, we point out the problems in the standard Jini service environment and analyze the Jgroup/ARM framework that has been developed in order to help fault tolerance of Jini services. In addition, we propose a secure Jini service architecture to satisfy the security, availability and quality of services on the basis of the analysis. The secure Jini service architecture we propose in this paper is able to protect a Jini system not only from faults such as network partition or server crash, but also from attacks exploiting flaws. It provides security mechanism for dynamic trust establishment among the service entities. Moreover, our secure Jini service architecture does not incur high computation costs to merge the user service states because of allocation of the replica based on each session of a user. Through the experiment on a test-bed, we have confirmed that proposed secure Jini service architecture is able to guarantee the persistence of the user service states at the level that the degradation of services quality is ignorable.

• KIPS Transactions on Computer and Communication Systems
• /
• v.6 no.9
• /
• pp.377-384
• /
• 2017

The performance improvement of a single core processor has reached its limit since the circuit density cannot be increased any longer due to overheating. Therefore, the multicore and manycore architectures have emerged as viable approaches and parallel programming becomes more important. Haskell, a purely functional language, is getting popular in this situation since it naturally supports parallel programming owing to its beneficial features including the implicit parallelism in evaluating expressions and the monadic tools supporting parallel constructs. However, the performance of Haskell parallel programs is strongly influenced by the performance of the run-time system including the garbage collector. Though a memory profiling tool namely GC-tune has been suggested, we need a more systematic way to use this tool. Since GC-tune finds the optimal memory size by executing the target program with all the different possible GC options, the GC-tuning time takes too long. This paper suggests a basic divide-and-conquer method to reduce the number of GC-tune executions by reducing the search area by one-quarter for every searching step. Applying this method to two parallel programs, a maximally independent set and a K-means programs, the memory tuning time is reduced by 7.78 times with accuracy 98% on average.

• Conservation Science in Museum
• /
• v.2
• /
• pp.77-82
• /
• 2000

The purpose of this study is to evaluate the effect of ART-SORB which is commonly used in museums and galleries at home and abroad including National Museum of Korea, so as to collect useful information to control micro-environment. Experiment was conducted in air-tight condition in order to evaluate only the effect of ART-SORB excluding any influence from outside factors. A certain amount of ART-SORB considering the case size and ART-SORB in cassette type were used to evaluate the humidity controlling capability. The result showed that target humidity was reached in 10~17 hours in case of using corresponding amount of ART-SORB to the cubic volume and in 5~6 hours in case of excessive use of cassette type ART-SORB. And it also showed that humidity can be controlled in the range of RH 50~70%. In addition, ART-SORB was excellent at raising humidity at low humidity and poor at high humidity. Therefore, ART-SORB turned out to be an effective humidity buffer for controlling micro-environment of such artifacts as wooden ware, lacquer ware and paintings, which require high humidity. However, unfortunately, there are some difficulties in applying this result to real condition, given the fact that this study was conducted under firm air-tight case. Therefore, ART-SORB can be fully effective only in firm air-tight case.

• Journal of the Korean Wood Science and Technology
• /
• v.46 no.1
• /
• pp.29-37
• /
• 2018

Bamboo is one of the major biomass resources in the world. To obtain valuable information for effective use of bamboo resources in Korea, the anatomical characteristics of the commercial Korean bamboo species (Phyllostachys pubescens, Phyllostachys nigra, and Phyllostachys bambusoides) were analyzed. The structures in bamboo culm were observed by optical and scanning electron microscopy. Also the crystalline properties as relative crystallinity and crystallite width were measured by an X-ray diffraction method. The three Korean bamboo species had the vascular bundle type I with tylosoid in intercellular space. In the outer part of culm, vascular bundles showed denser spacing than inner part. The fiber length in outer part samples of the three bamboo species showed longer than inner part samples. Furthermore, the fiber length showed a significant difference between inner part and outer part in three bamboo species, showing the longest fiber length in Phyllostachys bambusoides. Phyllostachys pubescens showed the greatest diameter in vessel and parenchyma on cross section. Parenchyma cells in Phyllostachys pubescens and Phyllostachys bambusoides showed similar length and width in both radial and tangential sections. The relative crystallinity and crystallite width in outer part samples of the three bamboo species showed higher values than those in inner part samples, with the greatest values from Phyllostachys bambusoides.

• Journal of Korean Society of Transportation
• /
• v.26 no.5
• /
• pp.163-174
• /
• 2008

The conventional four-step travel demand model is still widely used as the state-of-practice in most transportation planning agencies even though it does not provide reliable estimates of travel demand. In order to improve the accuracy of travel demand estimation, implementing an alternative approach would be critical as much as acquiring reliable socioeconomic and travel data. Recently, the role of travel demand model is diverse to satisfy the needs of microscopic analysis regarding various policies of travel demand management and traffic operations. In this context, the activity-based approach for travel demand estimation is introduced and a case study of developing a spatial-temporal activity presence-based approach that estimates travel demand through forecasting number of people present at certain place and time is accomplished. Results show that the spatial-temporal activity presence-based approach provides reliable estimates of both number of people present and trips actually people made. It is expected that the proposed approach will provide better estimates and be used in not only long-term transport plans but short-term transport impact studies with respect to various transport policies. Finally, in order to introduce the spatial-temporal activity presence-based approach, the data such as activity-based travel diary and land use based on geographic information system are essential.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.48 no.3
• /
• pp.19-29
• /
• 2011

Until now, many face recognition methods have been proposed, most of them use a 1-dimensional feature vector which is vectorized the input image without feature extraction process or input image itself is used as a feature matrix. It is known that the face recognition methods using raw image yield deteriorated performance in databases whose have severe illumination changes. In this paper, we propose a face recognition method using local statistics of gradients and correlations which are good for illumination changes. BDIP (block difference of inverse probabilities) is chosen as a local statistics of gradients and two types of BVLC (block variation of local correlation coefficients) is chosen as local statistics of correlations. When a input image enters the system, it extracts the BDIP, BVLC1 and BVLC2 feature images, fuses them, obtaining feature matrix by $(2D)^2$ PCA transformation, and classifies it with training feature matrix by nearest classifier. From experiment results of four face databases, FERET, Weizmann, Yale B, Yale, we can see that the proposed method is more reliable than other six methods in lighting and facial expression.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.5
• /
• pp.671-675
• /
• 2008

Based on information about the major microbial composition of kimchi and its relation to the taste, Leuconostoc mesenteroides K2M5 and Lactobacillus sakei K5M3 were selected as kimchi starter candidates. These two strains were found to be safe for industrial use because they showed neither harmful characteristics like ${\beta}$-hemolysis, ammonia and indole formation, and gelatin liquefaction, nor enzymatic activities like phenylalanine deaminase, ${\beta}$-glucuronidase, ${\beta}$-glucosidase, 7${\alpha}$-dehydroxylase and nitroreductase. Starter kimchi made with these strains were better in taste than the conventional kimchi when they are evaluated both by laboratory personnel and the public. Also microbial analysis of starter kimchi showed only starter bacteria after they were fermented to have the optimum acidity. Starter kimchi prepared with these two strains were not much different in physicochemical properties to the conventional kimchi except in that the starter kimchi were much higher in volatile organic acid content such as lactic acid. These results suggest that kimchi quality can be controlled to have consistent properties, both in taste and microbial composition, by using bacterial starters.