• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.39 no.3
• /
• pp.30-38
• /
• 2016

Shuttle-Based Storage/Retrieval System (SBS/RS) is relatively new to industry. The system is in the category of Automated Storage/Retrieval System (AS/RS), but it is different in that the SBS/RS uses shuttles as Storage/Retrieval (SR) machine instead using a stacker crane. The shuttles are assigned to each tier on multi-tier system and operated for pick-up or drop-off order. Since the system can handle multiple orders simultaneously, it can provide much higher throughput than that of general AS/RS with single stocker crane. Thus, this new system is well fit to recent tendency of increasing small quantity batch production and orders. One of the drawback of this system is that it needs a lot of investment to set up. The efficient operation of the system would be one of the critical matters to increase economic efficiency of capital investment. In this study, we focused on the dwell point policy for shuttles to find efficient way of operating the system. There are four basic policies for the dwell point and we had simulation-based experiment for two different scenarios based on the speed of the shuttle and inter-arrival time of the loads coming to the system combined with four different policies. As it was mentioned above, this SBS/RS relatively new to the field and there is no such experiment shown on previous research and the study of dwell point policy for this SBS/RS could provide the direct comparison of each policy with different hardware specification; the capability of the system. The policy that achieves most efficient operation among the given environment is proposed and the usability of the system is discussed.

• The Journal of the Korea Contents Association
• /
• v.9 no.1
• /
• pp.30-44
• /
• 2009

In this paper, we propose the mobile P2P structure supporting content searches for mobile peers efficiently. The proposed mobile P2P structure is a 3-tier structure which consists of a mobile peer, a mobile super peer, and a stationary super peer to reduce the content search cost of mobile P2P service. For content searches, mobile peer searches content in the communication range and performs hierarchical content searches which is using mobile super peer, stationary super peer for expansion of query region. In order to support hierarchial content searches and the continuity of services according to peer mobilities, peer's join/leave processes are explicitly stored by supporting message structures to the upper layer It is shown through experimental evaluation that the proposed structure improves about 32% contents search performance over the existing 2-tier structure. Since it also reduces the messages transferred to the stationary super peers, it reduced about 25% search loads of them.

• Journal of Distribution Science
• /
• v.16 no.4
• /
• pp.67-74
• /
• 2018

Purpose - Most of the amendments to the law on the improvement of the distribution structure of mobile communication terminal equipment, the fully self-sufficient system of terminals, and the separated disclosure system on the terminals are aimed at securing transparency of the distribution structure by eliminating or reducing handset subsidies. This study investigates what items are important for the purchase of mobile phones in various and rapidly changing mobile phone markets from the consumer's point of view and tries to make a strategic suggestion for future mobile distribution strategies. Research design, data, and methodology - The procedure of this study takes place in four steps. In step 1, only the SF type respondents selected for this study were extracted through MBTI analysis. In step 2, they were divided into three hierarchies for the AHP analysis and each element was arranged. In step 3, the AHP analysis was converted to a Fuzzy-AHP number using the trigonometric centroid method. This was to eliminate the ambiguity of the response by converting into a fuzzy number even if data consistency was maintained with CI value below 0.1. In step 4, the number of converted 2-layer and 3-layer was combined to derive the priority when the final handset is selected. Results - First, the highest importance among the four items in the second tier was the terminal function item, followed by brand, price, and design item. Second, in the third tier, the highest importance was level of after-sales service, followed by device price, processing speed, ease of use, usefulness, and rate system. Third, the arithmetic average of the determinant of the fuzzy function showed that processing speed, ease of use and usefulness in the function item, level of after-sales service in the brand item, and device price in the price item were the five most important factors among 16 choice factors. Conclusions - First, there will be a change in the consumption patterns of consumers who have compared distributors and dealers to purchase handsets with more subsidies. Second, it is highly likely that people will purchase new handsets only when they need to change their devices because they can not receive subsidies by switching phone brands any more.

• The KIPS Transactions:PartB
• /
• v.17B no.4
• /
• pp.309-316
• /
• 2010

This paper introduces a new model based method for facial expression recognition that uses facial grid angles as feature space. In order to be able to recognize the six main facial expression, proposed method uses a grid approach and therefore it establishes a new feature space based on the angles that each gird's edge and vertex form. The way taken in the paper is robust against several affine transformations such as translation, rotation, and scaling which in other approaches are considered very harmful in the overall accuracy of a facial expression recognition algorithm. Also, this paper demonstrates the process that the feature space is created using angles and how a selection process of feature subset within this space is applied with Wrapper approach. Selected features are classified by SVM, 3-NN classifier and classification results are validated with two-tier cross validation. Proposed method shows 94% classification result and feature selection algorithm improves results by up to 10% over the full set of feature.

• The Korean Nurse
• /
• v.29 no.5
• /
• pp.46-53
• /
• 1991

In the past, management had been done over nurses rather than nursing and this brought the existence of general manager and as a result, nurse-manager's position and role are being threatend. For the up-bringing of nursing to firm professional recognition in the 21st century, it is firmly believed that nursing managers are to be in the position to play the role of general manager with professional qualifications; personal qualities and exact understandings on the role and function of each tier group under her/his management. 124 top(3 nursing superintendents), middle-range(23 supervisors) and unit managers(98 head-nurses) from 3 university hospitals in Seoul were interviewed in order to investigate their belief in the role, professional qualifications, personal qualities as well as the strategy for the development of their leadership qualities. The frame of reference for the interview were developed by the researcher in reference to relevant literatures. It was the common belief that qualifications o[ top-managers and mid-managers require an educational background of master's preparation or higher and clinical career for at least 15 years for top-managers and 5 -10 years for mid-managers. The personal qualities required by nurse managers include; leadership, initiative, judgement, self-confidence, flexibility, open-mindedness and strong motivation. Achievment-orientedness would greatly help them become excellent managers. On the other hand, [or more effective management, managers of each teir group are to fully understand their role and perform "their job responsibilities ie. Top managers are supposed to study with emphasis on organization, function and conceptual s~ill while mid-managers concentrate their effort on the development of skills for direction, guidance and human relationship. Unit managers also supposed to have abilities to manage their function with emphasis on development of clinical performance skill, for direction on operative aspects. The strategies for the development of leadership qualities include program-planning at individual instutional level as well as local, national and international level. Nurse-managers are to be motivated and encouraged to participate in the programs in order to effectively communicate within tier groups.oups.

• Journal of The Korean Association of Information Education
• /
• v.7 no.2
• /
• pp.199-206
• /
• 2003

XML is becoming a new developing tool of web technology because of its ability of data management and flexibility in data presentation. So it's well researched that the reusability and integration with learning objects such as text, image, sound, video and plug-in programs of web contents in computer education. But the research for storing, extracting and integrating metadata about learning object was needed prior to implementing online learning system to integrate and manage it. Therefore this study propose a new method of using web service of DBMS for extracting learning object's metadata in database server which located in 3-tier system. To evaluate the efficiency of proposed method, The test server and two DBMSs(MS SQL Server 2000 and Oracle 9i) which have 30 metadata was implemented and the response time of it was measured. The response time of it was short, but in order to using this method the additional programming with SAX/DOM was necessary.

• Journal of KIISE:Computing Practices and Letters
• /
• v.9 no.5
• /
• pp.498-508
• /
• 2003

In the field of finance, Trading System of Securities is a very vulnerable application when it faces any small problems just for one minute. Since Trading System changes its environment from mainframes to client/server, its safety becomes the most important factor. Even though most If systems are configured by general guidelines currently, Trading System is an exception that it is configured by specific and rather ad hoc guidelines in order to ensure its safe management. In this thesis, I will prove the validity of specific and ad hoc configuration in the environment of Trading Systems where I use both XA interface system and Non-XA interface to configure its system based on 3-Tier Client/server computing environment through middleware, TP-Monitor, in the X/Open DTP Model. In order to validate the Trading System, I will compare and analyze the error of data of an order and ability to restore using both XA and Non-XA interfaces while testing take-over scenario on the assumption of the system's failure.

• The KIPS Transactions:PartD
• /
• v.10D no.6
• /
• pp.991-998
• /
• 2003

There are many methods to enhance the fault tolerance of the CORBA based real time systems by viewpoints. Among them, this paper provides a method to enable seamless services where the systems based on the CORBA have object's faults originated processing real time information. Namely, this paper observes a method to deal efficiently with object's faults happening in 3 tier architecture environments. It is possible to replicate objects as a way to enhance the fault tolerance considering object's faults. Along with it, this paper shows a method to enhance the fault tolerance ultimately and then keep the service continuity by prividing a way to allow to continue to run the systems until the FT-CORBA based one's faults are recovered.

• Journal of Advanced Marine Engineering and Technology
• /
• v.39 no.4
• /
• pp.418-424
• /
• 2015

Marine Environment Protection Committee of the International Maritime Organization has decided to reinforce the NOx emission standards for ships passing an ECA(Emission Control Area) with Tier III standards from January 1, 2016. In this study, real-time measurements of the exhaust gas, cylinder pressure and fuel consumption were conducted at each load of a T/S Hanbada main engine of Korea Maritime and Ocean University, which is controlled by single injection and double post injection for reducing NOx emissions. The results showed that the quantity of CO2 and NOx increased in proportion to the engine load, whereas the CO concentration was inversely proportional to the engine load. In addition, double post injection decreased 10 % of P-max and reduced 25~30 % of the NOx emissions compared to single injection, whereas there was a trade-off relation, such as increase 3~5 % of SFOC (Specific Fuel Oil Consumption).

• Journal of the Society of Disaster Information
• /
• v.19 no.1
• /
• pp.231-240
• /
• 2023

Purpose: The purpose of this study is to analyze air quality and carbon emissions in developing countries, particularly Myanmar, and explore the impact of transportation on CO2 emissions during peak hours relative to free-flow conditions. Method: This study conducted a traffic survey in two major cities in Myanmar to quantify carbon dioxide emissions from the transportation sector, using IPCC's tier 1 and tier 2 approaches, with statistical analysis performed using Python 3 and Microsoft Excel for comparative analysis of critical factors in CO2 emissions. Result: The result of this study is an estimate of the vehicle kilometers traveled (VKT) and fuel consumption in Yangon city for the year 2019, based on data from various sources including the Myanmar Statistical data base, YUTRA project survey, and Ministry of Electric and Energy. The study also analyzes the average travel time index (TTI) for the four roads in Yangon, which indicates the impact of congestion on vehicle travel time and CO2 emissions. Overall, the study provides important insights into the transport sector in Yangon city and can be used to inform policies aimed at reducing greenhouse gas emissions and improving traffic conditions. Conclusion: The study concludes that congestion plays a significant role in increasing fuel use and emission levels in the road transport sector in Myanmar. The analysis provides valuable insights into the impact of the sector on the environment and emphasizes the importance of addressing congestion to reduce fuel use and emissions. However, the study's scope is limited to Yangon city and Mandalay city, and some mean values may not accurately represent the entire country and other developing countries.