• Title/Summary/Keyword: Potential Strategy

Search Result 1,534, Processing Time 0.036 seconds

Toxicity of Nanomaterials and Strategy of Risk Assessment (나노물질의 독성과 위해성평가 전략)

  • Park, Kwang-Sik
    • Environmental Analysis Health and Toxicology
    • /
    • v.20 no.4 s.51
    • /
    • pp.259-271
    • /
    • 2005
  • Engineered nanoparticles exhibit a variety of unique and tunable chemical and physical properties. These unique properties make the nanoparticles central components and widespread potential applications in nanoindustry. However, the potential toxicities of nanoparticles have not been fully evaluated. Recently, the impacts of nanoparticles to human and environment became the emerging issue of toxicology. In this article, physicochemical properties and toxicities of carbon nanotube, fullerene, quantum dots, and other types of nanomaterials were reviewed and the strategy of risk assessment were suggested based on the frame of chemical assessment.

Managing Soil Contamination in the United States: Policy and Practice

  • Small, Matthew C.
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 2003.10a
    • /
    • pp.58-69
    • /
    • 2003
  • Soil contamination in the United States is managed using a risk-based decision making process. In other words, we don't ask, 'how much soil contamination can be cleaned up\ulcorner' Instead we ask, 'how much contamination can be safely left in place\ulcorner' The determination of 'safe' levels of contamination is based upon the potential for exposure and the toxicity of the contaminants of concern in soil. Potential for exposure is determined by evaluating potential exposure pathways from source to receptor given current or reasonably anticipated land use. Soil cleanup goals are then calculated for any complete exposure pathways based upon toxicity and the route of exposure. In some cases, institutional or engineering controls are also used to limit the potential for exposure. In order to prevent a continuous degradation of environmental quality, risk-based cleanup approaches must be combined with strong contamination prevention programs. In addition, alternative risk management approaches should be incorporated into an overall risk reduction strategy.erall risk reduction strategy.

  • PDF

Profiling Approach for the Choice between Speculation and Postponement Strategy in Supply Chain Management (공급사슬관리의 예측전략과 지연전략 선택을 위한 프로파일링 접근법)

  • Kang, Sung-Wook;Kim, Gyu-Bae
    • Journal of Distribution Science
    • /
    • v.12 no.4
    • /
    • pp.47-54
    • /
    • 2014
  • Purpose - The postponement strategy, which delays the form, place, and production of products as late as possible, has been widely considered as a competitive supply chain management scheme in an era of mass customization and modular manufacturing. An interesting business phenomenon is that not all manufacturing/logistics firms choose the postponement strategy. Given that postponement is a counter-measure to speculation, which has some advantages under certain environments, the current imprudent inclination toward the postponement strategy may cause firms to lose the potential of the speculation strategy, an alternative strategy in supply chain management. Building on the logistics and manufacturing literature, this study examines characteristics of two contrasting strategies, postponement and speculation, and major factors favoring each strategy. Research design, data, and methodology - We apply the profiling approach to two business cases, HP printer and LG mobile phone. The profiling approach is a method of choosing a particular strategy aligned with environmental factors. While various approaches have been used to check the fit between a business strategy and environmental factors, the literature on manufacturing strategy and logistics has commonly adopted the profiling approach. Major factors used in profiling variables are derived from the literature. Two samples, HP printer and LG mobile phone, are selected, because they represent major characteristics appropriate for each strategy. The profiling is based on data from semi-organized interviews with managers. Results - The profiling approach shows that the postponement strategy is a suitable one for HP printers. Most factors, such as product life cycle, large production volume, low-price, product value, and monetary density, support delaying end products until as late as possible. Despite some exceptions, such as delivery time and economy of scale, our analysis states that the overall profile of HP printer is favorable for the postponement strategy. On the other hand, LG mobile phone may adapt the speculation strategy. Although it has large production volume and low delivery frequency, most characteristics support the speculation strategy for this product. An interesting finding is that, despite common perception that advanced technology products such as mobile telephones favor the postponement strategy, profiling proposes the speculation strategy for this product. Conclusions - Our analysis shows that speculation is not the universal option for supply chain management, and that, when choosing a specific strategy, one should consider many factors simultaneously. A major implication of our work is to emphasize the role of environmental factors such as supply chain variables in choosing an inventory strategy, and the importance of fit rather than solely strategic orientation. A theoretical contribution is to demonstrate the benefit of the simultaneous consideration of business variables in choosing specific strategies. For practitioners, our work leads us to consider the existence and the potential of speculation as a counter-measure to postponement. In addition, the comprehensive framework in this research may be instantly used in examining a practical strategy.

A Portfolio Selection Strategy with Consideration of Growth Potential of Corporations (기업의 성장가능성을 고려한 포트폴리오 선택 전략)

  • Choi, Da-Young;Ahn, Beum-Jun;Shin, Hyun-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.9
    • /
    • pp.3849-3855
    • /
    • 2011
  • This study presents an efficient strategy for selecting portfolio by evaluating growth potential of a corporation based on dividend. Through preliminary experiments, we extract 4 categories to sort out prospective stocks and develop a scoring table including criteria and formulas used to calculate scores for each category. In order to show the effectiveness of the portfolio selected by scoring table, we constructed 3 portfolios for every 4 years (2007-2010) out of 927 listed companies in KRX and proved that our portfolios are superior to market portfolio in terms of rate of return.

UAV Swarm Flight Control System Design Using Potential Functions and Sliding Mode Control (포텐셜 함수와 슬라이딩 모드 제어기법을 이용한 무인기 군집비행 제어기 설계)

  • Han, Ki-Hoon;Kim, You-Dan
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.36 no.5
    • /
    • pp.448-454
    • /
    • 2008
  • This paper deals with a behavior based decentralized control strategy for UAV swarming utilizing the artificial potential functions and the sliding mode control technique. Individual interactions for swarming behavior are modeled using the artificial potential functions. The motion of individual UAV is directed toward the negative gradient of the combined potential. For tracking the reference trajectory of UAV swarming, a swarming center is considered as the object of control. The sliding-mode control technique is adopted to make the proposed swarm control strategy robust with respect to the system uncertainties and the varying mission environment. Numerical simulation is performed to verify the performance of the proposed controller.

A Novel Modulation Method for Three-Level Inverter Neutral Point Potential Oscillation Elimination

  • Yao, Yuan;Kang, Longyun;Zhang, Zhi
    • Journal of Power Electronics
    • /
    • v.18 no.2
    • /
    • pp.445-455
    • /
    • 2018
  • A novel algorithm is proposed to regulate the neutral point potential in neutral point clamped three-level inverters. Oscillations of the neutral point potential and an unbalanced dc-link voltage cause distortions of the output voltage. Large capacitors, which make the application costly and bulky, are needed to eliminate oscillations. Thus, the algorithm proposed in this paper utilizes the finite-control-set model predictive control and the multistage medium vector to solve these issues. The proposed strategy consists of a two-step prediction and a cost function to evaluate the selected multistage medium vector. Unlike the virtual vector method, the multistage medium vector is a mixture of the virtual vector and the original vector. In addition, its amplitude is variable. The neutral point current generated by it can be used to adjust the neutral point potential. When compared with the virtual vector method, the multistage medium vector contributes to decreasing the regulation time when the modulation index is high. The vectors are rearranged to cope with the variable switching frequency of the model predictive control. Simulation and experimental results verify the validity of the proposed strategy.

Real time navigaion strategy of a robile robot using artificial potential field

  • Chung, Yong-Hyun;Jin, Sang-Ho;Park, Jung-Il;Lee, Suck-Gyu;Lee, Dal-Hae
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1994.10a
    • /
    • pp.446-448
    • /
    • 1994
  • This paper proposes some dynamic navigation strategy for a mobile robot among multiple moving obstacles. The control force of the robot which consists of repulsive and attractive force is based on the artificial potential field. The artificial potential fields is derived with position or(and) velocities of the objects. The simulation results shows the properties of the proposed strategies.

  • PDF

Innovative Nuclear Power Plant Building Arrangement in Consideration of Decommissioning

  • Choi, Won-Jun;Roh, Myung-Sub;Kim, Chang-Lak
    • Nuclear Engineering and Technology
    • /
    • v.49 no.3
    • /
    • pp.525-533
    • /
    • 2017
  • A new concept termed the Innovative Nuclear Power Plant Building Arrangement (INBA) strategy is a new nuclear power plant building arrangement method which encompasses upfront consideration of more efficient decommissioning. Although existing decommissioning strategies such as immediate dismantling and differed dismantling has the advantage of either early site restoration or radioactive decommissioning waste reduction, the INBA strategy has the advantages of both strategies. In this research paper, the concept and the implementation method of the INBA strategy will be described. Two primary benefits will be further described: (1) early site restoration; and (2) radioactive waste reduction. Several other potential benefits will also be identified. For the estimation of economic benefit, the INBA strategy, with two primary benefits, will be compared with the immediate dismantling strategy. The effect of a short life cycle nuclear power plant in combination with the INBA strategy will be reviewed. Finally, some of the major impediments to the realization of this strategy will be discussed.

GIS Analysis on Siting Strategy of Offshore Wind Farm (해상풍력단지 입지전략 GIS 분석)

  • Song, Kyu-Bong;Kim, Hyun-Goo
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.06a
    • /
    • pp.460-462
    • /
    • 2009
  • This study has analyzed the scale, location, resource potential and feasibility of offshore wind farm scientifically and systematically based on the national wind map and GIS (Geographic Information System). For long-term wind power development, this study pursues siting strategy building, selection of target area and deciding development priority as well as the presenting a basis for assessment that are necessary for policy decision making by making theme layers under GIS environment. According to the analysis after organizing technological development by stages, even if only the most suitable sites are developed among the area of offshore wind farm candidates that can be developed under the current technological standard, it has been evaluated as being able to develop about 3 times of the wind power dissemination target until 2012. It is expected that about 5% of territorial water area can be developed in a short-term future while the southern offshore area possessing relatively favorable wind resource than the western offshore has been identified as the most feasible site. While about 23% of territorial water area has been classified as potential area for offshore wind farm development in a long-term future, even Jeju Island and offshore of Ulsan possessing excellent wind resource have been analyzed as feasible sites. The feasibility assessment of offshore wind farm development established by this study is expected to assist national strategy building for accomplishing the wind power dissemination target.

  • PDF

OPTIMAL TORQUE MANAGEMENT STRATEGY FOR A PARALLEL HYDRAULIC HYBRID VEHICLE

  • Sun, H.;Jiang, J.H.;Wang, X.
    • International Journal of Automotive Technology
    • /
    • v.8 no.6
    • /
    • pp.791-798
    • /
    • 2007
  • The hydraulic hybrid vehicle(HHV) is an application of hydrostatic transmission technology to improve vehicle fuel economy and emissions. A relatively lower energy density of hydraulic accumulator and complicated coordinating operations between two power sources require a special energy management strategy to maximize the fuel saving potential. This paper presents a new type of configuration for parallel HHV to minimize the disadvantages of the hydraulic accumulator, as well as a methodology for developing an energy management strategy tailored specially for PHHV. Based on an analysis of the optimal energy distribution between two power sources over a representative urban driving cycle with a Dynamic Programming(DP) algorithm, a fuzzy-based optimal torque management strategy is designed and developed to control the torque distribution. Simulation results demonstrates that the optimal torque management strategy maximizes the advantages of this hybrid type of configuration, and the high power density characteristics of hydraulic technology effectively improve the robustness of the energy management strategy and fuel economy of the PHHV.