• Journal of Biosystems Engineering
• /
• v.34 no.6
• /
• pp.404-410
• /
• 2009

This study was carried out to develop a self-propelled type explosive subsoiler for improving the root zone soil conditions in orchard and other forest fields. Prototype was designed to be able to inject air and other soil improving material such as lime into soil at the same time, and thus improve the air permeability and drainage of orchard soils to promote the root growth of tree for high quality fruit production. Soil penetration device of explosive subsoiler is composed of air hammer, penetration rob and air injection nozzle. To support the soil penetration device of explosive subsoiler to penetrate vertically, modified Scott-Russel mechanism was used. Timing control device for simultaneous injection of soil improving material with air was attached to the out side wall of air cylinder and as the cylinder move, the soil improving material was injected into soil at the same time. Turning radius of prototype was 2.2-2.3 m with good mobility in sloped land. It took approximately 1 minute for lime injection system to reach the optimum pressure of 9.9 kg/$cm^2$, average 10-20 seconds were required to rupture soil with the depth of 50 cm and 2-3 seconds were required for explosion, so all in all about 1 minute and 20 seconds were required for one cycle of explosion. Maximum soil rupture depth and diameter were 50 cm and 3-4 m respectively depending on the soil type and soil moisture content. For final design of explosive subsoiler inclination angle of lime hopper was increased from 60 degree to 70 degree and the shape of hopper was changed from rectangular cone to circular cone to solve the clogging problem of lime at out let. Agitating system operated by compressed air was attached to the metering device of the prototype, thus more than 90 cc of lime was discharged per cycle from metering device without clogging problems.

• The Journal of the Korea Contents Association
• /
• v.14 no.12
• /
• pp.618-628
• /
• 2014

A photograph used in a film poster summarizes the story of the film that lasts for around two hours. The image must contain a picture that represents the story and text including the title, with various design elements composed in a harmonious way. However, given that a photograph is the most noticeable element in a film poster, this study aims to examine the function, role, and types of a film poster and analyze poster photographs. Currently, there are companies specialized in photography for film posters, but sometimes recognized photographers are commissioned to take a photograph that will be used for a film poster. Hein-kuhn Oh actively produced such photographs in the early and mid-2000s, and this study deals with 'how the photographs recreate the content of the films' focused on three selected photographs taken by him. Also, There were commonalities found between the tree photographs and Oh's personal portrait photographs, which were then analyzed from the photographic aesthetic point of view. The three selected works are: , , and .

• Journal of the Korea Computer Industry Society
• /
• v.3 no.9
• /
• pp.1235-1244
• /
• 2002

This paper proposes a group key management protocol for a secure of all the multicast user in PIM-SM multicast group communication. With prosed architect, subgroups for multicast secure group management will be divided by RP (Rendezvous-Point) unit and each RP has a subgroup manager. Each subgroup manager gives a secure key to it's own transmitter md the transmitter compress the data with it's own secure key from the subgroup manager. Before the transmitter send the data to receiver, the transmitter prepare to encrypt a user's service by sending a encryption key to the receiver though the secure channel, after choking the user's validity through the secure channel. As the transmitter sending a data after then, the architecture is designed that the receiver will decode the received data with the transmitter's group key. As a result, the transmitting time is shortened because there is no need to data translation by group key on data sending and the data transmition is possible without new key distribution at path change to SPT (Shortest Path Tree) of the router characteristic. Additionally, the whole architecture size is samller than the other multicast secure architecture by using the conventional PIM-SIM routing structure without any additional equipment.

• Journal of Korea Multimedia Society
• /
• v.6 no.3
• /
• pp.384-396
• /
• 2003

Hybrid query processing method is used for preventing server overload that is created by heavy user connection in Web GIS. In Hybrid query processing method, both server and client participate in spatial query processing. But, Hybrid query processing method is restricted in scalability of server and it can't be fundamentally solution for server overload. So, it is necessary for Web GIS to be brought in web clustering technique. In this thesis, we propose load-balancing method that uses proximity of query region. In this paper, we create tile groups that have relation each tile in same group is very close, and forward client request to the server that can have maximum rate of buffer reuse with considering characteristic of spatial query. With out load balancing method, buffet in server is optimized for exploring spatial index tree and increase rate of buffer reuse, so it can be reduced amount of disk access and increase system performance.

• Journal of KIISE:Software and Applications
• /
• v.26 no.9
• /
• pp.1039-1051
• /
• 1999

시공간 데이타베이스는 현실세계의 객체에 대하여 효율적인 공간 관리와 이력 관리를 지원한다. 이러한 시공간 데이타베이스는 시간차원과 공간차원이라는 이질적 데이타 공간을 관리하여야 하는 대단히 복잡한 시스템이다. 따라서 데이타에 대한 효율적 접근 방법에 대한 연구가 필수적이며, 이는 효율적 색인 기법의 개발을 통하여 이룰 수 있다. 그러나 시공간 데이타에 대한 접근방법 연구는 거의 이루어지지 않고 있으며 극소수의 사례들마저도 공간 객체의 이력 개념을 지원하는 것이 아니라 멀티미디어 객체의 상대적 시간만을 지원하고 있다. 따라서 이 논문에서는 공간 데이타의 이력을 표현하는 시공간 데이타에 대하여 효율적으로 색인하기 위한 방안으로서 시간과 공간을 단일화된 색인 영역으로 통합하는 단일화된 시공간 색인 모델을 제시하고, 이를 기존의 R-트리를 기반으로 확장한 색인을 설계 및 구현하였으며, 아울러 다양한 유형의 시공간 연산에 대한 색인의 성능을 평가하였다.Abstract Spatiotemporal databases are able to support an efficient spatial management as well as historical management for an object in the real world. It is very complex to manage these two dimensions why there exists on difference of inborn property of temporal and spatial dimensions. Therefore an efficient access method should be studied, and it can be done by means of development of efficient indexing technology.However, there is a few related work in the research of access methods of spatiotemporal data. Also the previous works do not support the concept of history for spatial object, and only support the relative time among multimedia objects. Therefore, in this paper, we propose a unified Spatiotemporal index model as an efficient index for Spatiotemporal data. And we not only design Spatiotemporal index that has been extended to historical management facility on the basis of conventional R-tree, but also implement it. Finally we have evaluated performance of index for the various kinds of Spatiotemporal operations.

• Journal of information and communication convergence engineering
• /
• v.6 no.2
• /
• pp.117-121
• /
• 2008

In ad hoc network, the scarce energy management of the mobile devices has become a critical issue in order to extend the network lifetime. Therefore, the energy consumption is important in the routing design, otherwise cluster schemes are efficient in energy conserving. For the above reasons, an Energy conserving Context aware Clustering algorithm (ECC) is proposed to establish the network clustering structure, and a routing algorithm is introduced to choose the Optimal Energy Routing Protocol (OERP) path in this paper. Because in ad hoc network, the topology, nodes residual energy and energy consuming rate are dynamic changing. The network system should react continuously and rapidly to the changing conditions, and make corresponding action according different conditions. So we use the context aware computing to actualize the cluster head node, the routing path choosing. In this paper, we consider a novel routing protocol using the cluster schemes to find the optimal energy routing path based on a special topology structure of Resilient Ontology Multicasting Routing Protocol (RODMRP). The RODMRP is one of the hierarchical ad hoc network structure which combines the advantage of the tree based and the mesh based network. This scheme divides the nodes in different level found on the node energy condition, and the clustering is established based on the levels. This protocol considered the residual energy of the nodes and the total consuming energy ratio on the routing path to get the energy efficiently routing. The proposed networks scheme could get better improve the awareness for data to achieve and performance on their clustering establishment and messages transmission. Also, by using the context aware computing, according to the condition and the rules defined, the sensor nodes could adjust their behaviors correspondingly to improve the network routing.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.1
• /
• pp.182-192
• /
• 1999

The advance of the MPEG(Moving Picture Expert Group) and DSP(Digital Signal Processing) technologies lead the energence of the information appliances which are gradually digitalized and embedded the high-speed networking function. This paper proposes a CHANCE(Cost-effective Home ATM Network for the Consumer Electronics) protocol supporting the ATM-based high-speed networking between the information appliances within the home, and designs its specific functions including the network management and signalling function. The CHANCE protocol is basically based on the tree topology, and supports the plug-and-play function by using only the header field of the ATM cells. Unlike the existing ATM Warren protocol which uses the source routed addressing scheme to control the in-home devices from the Warren controller, the CHANCE protocol can support the inter-device controls as well as the controls from the CHANCE controller by using the switch and device identifier.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.9 no.2
• /
• pp.30-41
• /
• 2006

This paper proposes an e-logistics system supporting efficient vehicle moving trajectory management. Recent advances in wireless communications have given rise to a number of location-based services including logistics vehicle tracking, cellular phone user's location finding, and location-based commerce. Logistics systems typically entail tracking vehicles for purposes of the logistics center knowing the whereabouts of the vehicles and/or consignments. Moreover, storing and managing location trajectory of continuously moving vehicles and consignments is necessary for supporting efficient logistics plan and consignment. The proposed system is able to manage spatial objects in GIS as well as logistic information in the mobile environment. And for the efficiently managing and retrieving of transporting trajectory of logistics, we extend previous moving object indexing method, TB-Tree, to use multi-version framework and evaluate data updating performance. It is able to apply the proposed method to develop mobile contents services based on continuously changing location of moving object in the mobile environment.

• Convergence Security Journal
• /
• v.9 no.2
• /
• pp.71-78
• /
• 2009

It is very difficult to apply previous security protocols to WSNs(Wireless Sensor Networks) directly because WNSs have resource constrained characteristics such as a low computing ability, power, and a low communication band width. In order to overcome the problem, we proposes a secure group communication scheme applicable to WSNs. The proposed scheme is a combined form of the TEEN(Threshold sensitive Energy Efficient sensor Network protocol) clustering based hierarchical routing protocol and security mechanism, and we assume that WSNs are composed of sensor nodes, cluster headers, and base stations. We use both private key and public key cryptographic algorithms to achieve an enhanced security and an efficient key management. In addition, communications among sensor nodes, cluster headers, and base stations are accomplished by a hierarchical tree architecture to reduce power consumption. Therefore, the proposed scheme in this paper is well suited for WSNs since our design can provide not only a more enhanced security but also a lower power consumption in communications.

• KIEAE Journal
• /
• v.10 no.2
• /
• pp.39-48
• /
• 2010

PAJU Book City Plan was designed to integrate two concepts of "Publishing Productive City" and "Ecological City" with the goal of "bringing of human being and nature together". This research on the post occupancy evaluation on PAJU Book City has two aims; One is to define how people, mainly working there rather than living, recognize the city and the other is to identify the problems resulted from the first phase of planning process and to suggest feasible solutions at the same time. It would be desirable that the outcome of this research should be used as data sources to improve the second phase of the plan. The evaluation criteria were created by the pre-survey on the basis of previous researches and "Pa Ju publishing city architectural design guide book (1999)". With those criteria, on-site questionnaire was conducted among people who work in PAJU Book City and stratified sampling was used for the proper sampling. The result is as follows; the visual-aesthetic criteria had positive response, which also closely related to a city satisfaction. Considering this result, construction type, circumferential environment of the building and a place of building form were found appropriate. The evaluation on the physical-ecological criteria was relatively low. Respondents were unsatisfied with green space and required better ecological waterway and more roadside tree. As green space was given a lot of weight in satisfaction survey, more green urban areas should be planned in the next phase. The evaluation on the social-behavior criteria got the lowest score. Particularly, the accessibility and convenient facilities were remarkably low. Nonetheless, the self-conceit about PAJU Book City was highly evaluated and played a crucial role in a city satisfaction. In order to achieve the goal, physical beauty, characteristics as a publication city as well as an ecologically sustainable city should be main agenda in the second phase of Paju Book City Plan. Consequently, it is important to strike a balance between the external environment and image media in order that PAJU Book City should be re-born as a culture city.