• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.6
• /
• pp.4002-4006
• /
• 2014

The automotive exhaust gases generated by the vehicles containing carbon monoxide, hydrocarbons and lead, is a large concern because of their harm to human health or the living environment. To reduce exhaust gas, it is important to develop a variety of techniques that are currently being used by elemental analysis to determine the optimal conditions. In this study, the anti-freeze coolant contained in the exhaust gas was examined, which can affect the emissions. The effects of the commercially available coolant from five domestic companies on the HC, NOx and $CO_2$ emissions were analyzed to determine the optimal amount of antifreeze. In addition, antifreeze products from the five companies were analyzed with respect to driving time of the cooling fan and the correlation of the NOx emission analysis. The temperature of the engine oil was matched using a manual gear of small passenger inspection standard speed $40{\pm}2Km/h$ so the vehicle could meet the specifications for inspection $90{\sim}93^{\circ}C$. The Company D fan operation time resulted in the shortest antifreeze, $CO_2$ and NOx emissions.

• Korean Journal of Construction Engineering and Management
• /
• v.12 no.1
• /
• pp.23-32
• /
• 2011

Domestic leading construction companies has been establishing and performing TACT scheduling method, similar to linear scheduling model such as line of balance and repetitive schedule, and etc. in which repetitive construction works are involved like high-rise building. Linear scheduling model has been researched as a visual scheduling method presenting the work space and time information. Likewise scheduling constraints of CPM network such as finish-to-finish, start-to-start, finish-to-start, start-to-start, linear scheduling model also has the relationships constraints, namely boundary conditions, between activities. It is especially necessary to define the boundary conditions of the activities' relationships in order to apply the linear scheduling model to be compatible with the network schedule. Therefore, this research considers the boundary conditions between activities for establishing the linear scheduling model. This paper also applies the proposed boundary conditions to TACT schedule and then deduces the main considerations in order to establish and perform TACT schedule.

• Journal of the Society of Naval Architects of Korea
• /
• v.46 no.1
• /
• pp.78-86
• /
• 2009

A capacity calculation and process analysis is a very important part for the entire ship production planning. Ship's production plan is set up with a concept that the product is produced based on the capacity achievable by the processes while general manufacturing sets up the production plan based on product lead-time. Therefore, in case the calculation of capacity for each process of shipbuilding yard is different from actual conditions, a series of production plan - ship table composition, dual schedule plan and execution schedule plan, etc - may accumulate errors, lose reliability of planning information and cause heavy cost deficit in this course. In particular, in case of new shipbuilding yard, stocks between processes are built up and half blocks are not supplied in timely manner, and that is sometimes due to the clumsiness of the operator but it is more often because of the capacity to execute each process is not logically calculated. Therefore, this paper presents the process to calculate the assembly leadtime and assembly process capacity for shipbuilding yard assembly factory. This paper calculated the block type for calculation of assembly lead time based on block DAP(detailed assembly procedure), and introduced cases that calculate production capacities by assembly surface plate by considering the surface plate occupied area of the blocks that change depending on assembly field area and assembly processes through assembly simulation.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.9
• /
• pp.13-19
• /
• 2008

Time synchronization of nodes in sensor network synchronizes sensor nodes to one time clock. This is very essential in sensor networks so that the information collected and reported from the sensor nodes becomes meaningful. If sensor nodes are not synchronized, disaster report with time information can be wrong analyzed and this may lead to big calamity. With the limitation of battery and computing power, time synchronization algorithm imported in sensor nodes has to be as simple as it doesn't need big complexity, nor generates many synchronization messages. To reduce the synchronization error, hop count should be kept small between reference node to initiate synchronization and sensor nodes to be synchronized. Therefore, multiple reference nodes are used instead of single reference node. The use of multiple reference nodes introduce the requirement of synchronization among reference nodes in the network. Several algorithms have been proposed till now, but the synchronization among reference nodes are not well considered. This paper proposes improved time synchronization for sensor networks by synchronizing multiple reference nodes inside the network. Through simulation, we validated the effects of new algorithm.

• Journal of Multimedia Information System
• /
• v.4 no.3
• /
• pp.157-162
• /
• 2017

The title of this project is "A Simple Interactive 3D Interior Design Application for Living Room - Cost Management", focusing on developing an application that enables costing and designing to be executed concurrently in interior design phases. This is because any changes made at costing phase after design phase is completed, it will potentially lead to unnecessary increase in cost and time. Therefore, the objective of this project is aimed to devise a cost management module to be included in the proposed application, allowing interior designer to make cost-based decision at the designing phase itself. This can be achieved through its proposed functions which include total cost update, budget management, cost estimator calculator and material list generation. The methodology being proposed in this project is Prototyping Development, categorized under Rapid Application Development (RAD), by starting off with planning, analysis, design and implementation phases are performed concurrently and repeatedly in a cycle to produce a prototype until the application is completed. In the end of this project, the developed prototype is expected to contribute a better solution towards cost management in interior design.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.7
• /
• pp.1610-1623
• /
• 2013

In-network caching is a key component of information-centric networking (ICN) for reducing content download time, network traffic, and server workload. Data center network (DCN) is an ideal candidate for applying the ICN design principles. In this paper, we have evaluated the effectiveness of caching placement and replacement in DCN with butterfly-topology. We also suggest a new cache placement policy based on the number of routing nodes (i.e., hop counts) through which travels the content. With a probability inversely proportional to the hop counts, the caching placement policy makes each routing node to cache content chunks. Simulation results lead us to conclude (i) cache placement policy is more effective for cache performance than cache replacement, (ii) the suggested cache placement policy has better caching performance for butterfly-type DCNs than the traditional caching placement policies such as ALWASYS and FIX(P), and (iii) high cache hit ratio does not always imply low average hop counts.

• Journal of the Korean Data and Information Science Society
• /
• v.21 no.4
• /
• pp.783-793
• /
• 2010

Several multi-hop applications developed for vehicular ad hoc networks use broadcast as a means to either discover nearby neighbors or propagate useful traffic information to other vehicles located within a certain geographical area. However, the conventional broadcast mechanism may lead to the so-called broadcast storm problem, a scenario in which there is a high level of contention and collisions at the link layer due to an excessive number of broadcast packets. We present a fuzzy alert message dissemination algorithm to improve performance for road safety alert application in Vehicular Ad-hoc Network (VANET). In the proposed algorithm, when a vehicle receives an alert message for the first time, the vehicle rebroadcasts the alert message according to the fuzzy control rules for rebroadcast degree, where the rebroadcast degree depends on the current traffic density of the road and the distance between source vehicle and destination vehicle. Also, the proposed algorithm is the hybrid algorithm that uses broadcast protocol together with token protocol according to traffic density. The performance of the proposed algorithm is evaluated through simulation and compared with that of other alert message dissemination algorithms.

• Journal of the Speleological Society of Korea
• /
• no.70
• /
• pp.29-35
• /
• 2006

21 century as the knowledge base society which demands an originality and a variety the updated technology and knowledge creation ability quality and national power of life of the citizen were under controlling. Consequently, the extension of development and originality of the ability which is various leads and studying voluntary character and the ability back the education which it considers actively it raises and the infield it does. With activation plan of cave resources home page of Speleological Society of Korean like home page of Speleological Society of Japan cave crane information, caving information, cave Q/A, cave publication, the relation site back the possibility of seeing information regarding the cave which is various in order to be, it reorganizes. The possibility of coming in contact in order to be, various branch information also the general rain specialist regarding the cave resources. Currently the possibility of seeing the various branch data for the application of the cave resources at any time it is, home page of Speleological Society of Korean the possibility of doing to lead in order to be, it proposes the plan. From one person it will be able to study the data regarding the cave of various field in order, all curricular materials regarding the cave resources the educational program which leads a home page about under developing it proposes the activation plan of the cave resources.

• Journal of Korea Spatial Information System Society
• /
• v.8 no.2 s.17
• /
• pp.1-11
• /
• 2006

This paper addresses a GIS (Geographic Information System) based system in order to reduce the rate of public transportation accidents occurring in Iranian roads network. Over the years, the road accidents are a major issue throughout the world. Today, particular consideration is given to those technologies which can lead to diminish on the number of critical incidents. One of the main factors resulting in accidents and fatalities rates growth is the speed violation of buses in Iranian road network. The conventional speed controlling approach in Iran based on the Tachograph which records vehicle's speed, time, and stoppage in the mechanical processing has many problems. Hence, this research is intended to design and implement a GIS-based system to manage road accident of Bus transportation system using offline tracking system. This was accomplished using a GIS-based technique that encompasses three steps. The first step is developing a GIS-based accident system. The second step includes designing and applying a tracking system inside 90 buses for recording Bus information for speed controlling. Lastly, by using mentioned system in police center, the illegal drivers' punishment would be considered properly. Overall, this system has been successfully applied in this work. Therefore, the police and transportation office are able to control and make policy to diminish the number of accident. It is anticipated that online tracking system through the Web GIS would be utilized In this system in the near future.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.6 no.9
• /
• pp.2170-2190
• /
• 2012

There are nowadays strong demands for intelligent surveillance systems, which can infer or understand more complex behavior. The application of crowd density estimation methods could lead to a better understanding of crowd behavior, improved design of the built environment, and increased pedestrian safety. In this paper, we propose a new crowd density estimation method, which aims at estimating not only a moving crowd, but also a stationary crowd, using images captured from surveillance cameras situated in various public locations. The crowd density of the moving people is measured, based on the moving area during a specified time period. The moving area is defined as the area where the magnitude of the accumulated optical flow exceeds a predefined threshold. In contrast, the stationary crowd density is estimated from the coarseness of textures, under the assumption that each person can be regarded as a textural unit. A multilayer neural network is designed, to classify crowd density levels into 5 classes. Finally, the proposed method is experimented with PETS 2009 and the platform of Gangnam subway station image sequences.