• Journal of Electrical Engineering and Technology
• /
• v.10 no.4
• /
• pp.1480-1491
• /
• 2015

In new deregulated electricity market, short-term price forecasting is key information for all market players. A better forecast of market-clearing price (MCP) helps market participants to strategically set up their bidding strategies for energy markets in the short-term. This paper presents a new prediction strategy to improve the need for more accurate short-term price forecasting tool at spot market using an artificial neural networks (ANNs). To build the forecasting ANN model, a three-layered feedforward neural network trained by the improved Levenberg-marquardt (LM) algorithm is used to forecast the locational marginal prices (LMPs). To accurately predict LMPs, actual power generation and load are considered as the input sets, and then the difference is used to predict price differences in the spot market. The proposed ANN model generalizes the relationship between the LMP in each area and the unconstrained MCP during the same period of time. The LMP calculation is iterated so that the capacity between the areas is maximized and the mechanism itself helps to relieve grid congestion. The addition of flow between the areas gives the LMPs a new equilibrium point, which is balanced when taking the transfer capacity into account, LMP forecasting is then possible. The proposed forecasting strategy is tested on the spot market of the Nord Pool. The validity, the efficiency, and effectiveness of the proposed approach are shown by comparing with time-series models

• Journal of the Korean Society of Systems Engineering
• /
• v.10 no.2
• /
• pp.59-69
• /
• 2014

In the bidding stage of turn-key based plant construction contracts, owners provide design and performance basis for contractors instead of giving design drawing. To win the bid for a plant construction, the contractors should be obliged to satisfy and ensure owners'requirements such as design and performance basis in a plant construction project, In other words, owners imposes technical risk of the design to the contractors by specifying responsibility for the analysis and verification of the plant construction. Thus, it is very important that contracters make accurate and realistic basic design plan in a short period of time. To deal with such a situation, we propose a systems engineering approach for the analysis and management of the technical risk. Specifically, we first: 1) Analyzes technical risk related with the plant design information for the bidders, followed by 2) Developing stakeholder requirements for the basic engineering design, and 3) System requirements for dealing with technical risk. Also, in this paper, we proposed converting method from MOE(Measure of Effectiveness) to MOP(Measure of Performance) in the risk analysis. To show the effectiveness of the proposed method, we carried out a case study.

• 한국전산유체공학회:학술대회논문집
• /
• 2008.03b
• /
• pp.381-384
• /
• 2008

This paper presents an operational technique to maximize profit of a cogeneration power plant. To minimize errors in a loss and gain analysis of a cogeneration power plant, the energy sale profit in the cost-based-pool electric power trade market, the heat sale profit, and the supplementary fund profit for electric power industry are taken into consideration. The objective is to optimize the heat-electric power ratio to maximize profit of a cogeneration power plant. Furthermore, the constrained bidding technique to optimize heat-electric power ratiocan be obtained. Profits from of a cogeneration power plant are composed of three categories, such as the energy sale profit in the cost-based-pool electric power trade market, the heat sale profit, and the supplementary fund profit for electric power industry. Profits of a cogeneration power plant are varied enormously by the operation modes. The profits are mainly determined by the amount of constrained heat generation in each trading time. And the three profit categories arecoupled tightly via the heat-electric power ratio. The result of this case study can be used as a reference to a cogeneration power plant under the power trading system considered in this case.

• The Journal of Society for e-Business Studies
• /
• v.8 no.4
• /
• pp.53-68
• /
• 2003

Currently, it is possible to buy almost anything from books(Amazon.com) to airplane tickets(Travelocity.com) using the world wide web. The purpose of this research is to develop a "clean interface" between design and fabrication facilities for the production of custom machined parts through Internet. The current mechanism for production of prototype parts that can be fabricated using standard machine tools like milling machines, requires a process of part description preparation, bidding, contract award, and finally fabrication and delivery of the part. This is a substantially more complex process than buying a book or airplane ticket. In this paper, we try to define the ambiguous part description using XML based data exchange format and to enable e-commerce in this field. The research accomplishments are summarized: 1. Creation of a new format for data exchange of machined prototype parts, 2. Development of a prototype system to illustrate how the XML data can be effectively used to conduct e-Commerce for custom machined parts, 3. Testing of the methodology with a number of parts.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.8 no.5
• /
• pp.979-983
• /
• 2007

In this thesis, a strip layout drawing of LCD S/C (shield case) was prepared. In the press die, strip layout drawing is a major factor that decides the mass production of a product. The 3D CAD/CAM system was applied for the easy correction of the interference factor with other parts to be mounted. The material use ratio was enhanced to 60.17% by optimizing the blank layout and strip layout in double width array. Furthermore, the flatness of the product was made to fit the requirements by adding the bidding process intensively on the notching part where the occurrence of the change in shape is expected owing to the thin material. For the 3D CAD/CAM software, Unigraphics NX3.0 was used. The strip layout drawing was prepared in 12 processes.

• Journal of Fashion Business
• /
• v.12 no.5
• /
• pp.155-167
• /
• 2008

With globalization and competitive market environment, companies realize how marketing channels are important in order to survive and succeed the business. The importance of information management among channels is getting increased, and is needed for SCM. Nevertheless having hard situation to implement SCM, SCM for textile fashion industry engaged in small business mostly is the way to break through the difficulty on so many channels to go through from fiber to retail. Therefore, the purpose of this case study to L firm by using questionnaire based interviewing method was to investigate how textile fashion small business can implement the SCM with their own differentiated strategy differed from a large corporation. L firm conducted SCM-ISN (Information Service Network) under the restructuring project. So they could use electronic bidding system via internet and have information sharing with their partners such as retailers. Therefore, they could expand market share to Seoul and reduce inventory and manage their customer more effectively than before.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.800-807
• /
• 2009

The limited public funds available for infrastructure projects have led governments to consider private entities' participation in long-term contracts for finance, construction, and operation of these projects to share risks and rewards between the public and the private. Because these projects have complicated risk evolutions, diverse contractual forms for each project member to hedge risks involved in a project are necessary. In light of this, Build-Operate-Transfer(BOT) model is considered as effective to accomplish Public Private Partnerships(PPPs) with a characteristic of an ownership-reversion. In BOT projects, the government has used such an incentive system as minimum revenue guarantee(MRG) agreement to attract the private's participation. Although this agreement turns out critical in success of BOT project, there still exist problematic issues in a financial feasibility analysis since the traditional capital budgeting theory, Net Present Value(NPV) analysis, has failed to evaluate the contingent characteristic of MRG agreement. The purpose of this research is to develop real option model based on option pricing theory so as to provide a theoretical framework in valuing MRG agreement in BOT projects. To understand the applicability of the model, the model is applied to the example of the BOT toll road project and the results are compared with that by NPV analysis. Finally, we found that the impact of the MRG agreement is significant on the project value. Hence, the real option model can help the government establish better BOT policies and the developer make appropriate bidding strategies.

• Korean Journal of Heritage: History & Science
• /
• v.55 no.1
• /
• pp.111-132
• /
• 2022

The comprehensive examination on tendering system has been introduced to the Cultural Heritage repair and restoration field since 2016 to remedy the repair issues of South Gate in 2014. The Cultural Heritage Administration tried to attain the high performance of the cultural heritage repair and restoration works securing the proper payment for the repair and restoration works. It is high time to review the operating performance of the comprehensive examination on tendering system (hereinafter referred to as the "CEOTS"), as the system has been run for over 5 years to correspond with its original goal, i.e., "The Proper Payment in return for the High Performance of Repair and Restoration works." This study intends to analyze 114 tenders of CEOTS from 2016 to 2020. As a result of the analysis of 114 tenders, firstly, more than half of bid winners were in the top 20% of repair & restoration capacity disclosure amount list, which mostly fulfilled the goal of 'attaining high performance.' Secondly, as the winning bid rate is decreasing from 86.847% in 2017 to 85.488% in 2020, the goal of 'guarantee of a proper payment' is not achieved yet. Thirdly, the influence of Economic Evaluation section in CEOTS has been grown since the change of scoring system in CEOTS in 2019. This study identifies two reasons why the winning bid rate of CEOTS has decreased. Firstly, it is caused by the fact that 'the group that got more than 1st place' and 'the first place group' that are more than half of the total bidders have the decreasing bidding rate trend as the years go by. Secondly, the exclusion rate of 'the group that got more than 1st place' is higher than the exclusion rate of 'the group that got less than 1st place', which means the expected winning rate would be lowered. It is proposed that the revision of CEOTS code is needed, i.e. easing the strict rule concerning the exclusion rate as well as setting up the lower bidding limit to prevent the excessive decreasing winning bid rate.

• Korean Journal of Construction Engineering and Management
• /
• v.13 no.3
• /
• pp.122-130
• /
• 2012

Currently, TK(Turn-key) projects have been implemented, the projects on TK basis still have shown several problems rather than its own merits as a bidding method. Increasing the number of claims being occurred during construction process of the projects is reality because of unclear notice of tender documents and conditions of the contract, design review system, and decision process of the qualified bidder. To establish desirable TK projects in domestic market, not only should resonable alternatives for carrying out design review system and selecting the bid winner be set up, but also proper standards for reforming irrational system of contract, bid, and notice of tender related to TK projects. This study is intended to reduce the number of claims and implement efficient projects of apartment construction on TK basis by identifying potential problems through analysis of claim examples of TK projects which have difficulties of revising contract agreement such as drawings and suggesting improvement methods for contract conditions and notice of tender docuements.

• Korean Journal of Construction Engineering and Management
• /
• v.7 no.2 s.30
• /
• pp.109-117
• /
• 2006

Recent rapid changes such as construction market reduction, lowest bidding system of construction cost, five days per week system, and post-construction sale system are inevitably accelerating the competitiveness between construction companies. Those rapid changes of construction environment require construction companies, which are main participants of construction industry, to adapt to the changes and more to lead new construction environment. However, there are many construction uncertainties which could delay construction completion. Without the proper identification of construction uncertainties, structured strategy establishment and management of construction schedule, the competitive advantages of construction duration could not be made. Thus this paper limited the research boundary to construction duration competitiveness instead of general strategy establishment. Recognizing the importance of proper calculation of construction duration, requirements of construction duration reduction and limited researches related to construction schedule strategy, we established the 25 strategies for construction duration competitivenss by internal and external construction environment analysis and SWOT analysis, and then elicited the first considerations to accomplish the strategies through concensus of all the staffs by questionnaire, brainstroming and face-to-face interviews.