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971.
Recently, Kim and Bell ( 2011 ) developed a revenue managemnent pricing model with price‐driven substitution. The authors considered production decisions under unlimited production capacity and investigated the impact of price‐driven substitution on a firm's pricing and production decisions. The authors modeled the consumer demands for each market segment as linear additive demand function based on exogenous variables, where demand substitution occurred as a function of price differences between the two products. In this article, we extend this work to examine the impact of a production capacity constraint on the firm's joint pricing and inventory decisions. Based on this extended model, we investigate the impact of price‐driven substitution on a firm's pricing and production decisions where there is a limit on total capacity. We show how revenue managers should adjust prices and production levels to take into account price‐driven substitution under a capacity constraint setting. Both deterministic and stochastic models are developed, and the impact of price‐driven substitution and a capacity constraint on the optimal prices, production levels, and revenues is illustrated. 相似文献
972.
Synthetic vision systems (SVS) render terrain features for pilots through cockpit displays using a GPS database and three‐dimensional graphical models. Enhanced vision systems (EVS) present infrared imagery of terrain using a forward‐looking sensor in the nose of an aircraft. The ultimate goal of SVS and EVS technologies is to support pilots in achieving safety under low‐visibility and night conditions comparable to clear, day conditions. This study assessed pilot performance and situation awareness (SA) effects of SVS and EVS imagery in an advanced head‐up display (HUD) during a simulated landing approach under instrument meteorological conditions. Videos of the landing with various HUD configurations were presented to eight pilots with a superimposed tracking task. The independent variables included four HUD feature configurations (baseline [no terrain imagery], SVS, EVS, and a combination of SVS and EVS), two visibility conditions, and four legs of the flight. Results indicated that SVS increased overall SA but degraded flight path control performance because of visual confusion with other display features. EVS increased flight path control accuracy but decreased system (aircraft) awareness because of visual distractions. The combination of SVS and EVS generated offsetting effects. Display configurations did not affect pilot spatial awareness. Flight performance was not different among phases of the approach, but levels and types of pilot SA did vary from leg to leg. These results are applicable to development of adaptive HUD features to support pilot performance. They support the use of multidimensional measures of SA for insight on pilot information processing with advanced aviation displays. © 2012 Wiley Periodicals, Inc. 相似文献
973.
We demonstrate a novel fabrication technology of the microneedle array applied to painless drug delivery and minimal invasive blood extraction. The fabrication technology consists of a vertical deep X-ray exposure and a successive inclined deep X-ray exposure with a deep X-ray mask whose pattern has a hollow triangular array. The vertical exposure makes triangular column array with a needle conduit. With the successive inclined exposure, the column array shapes into the microneedle array without deep X-ray mask alignment. Changing the inclined angle and the gap between the mask and PMMA (PolyMethylMetaAcrylic) substrate, different types of microneedle array are fabricated in 750–1000 m shafts length, 15o–20o tapered tips angle, and 190–300 m bases area. The masks are designed to 400–600 m triangles length, 70–100 m conduits diameter, 25–60EA/5 mm2 arrays density, and various tip shapes such as triangular, rounded, or arrow-like features. In the medical application, the fabricated PMMA microneedle array fulfills the structural requirements such as three-dimensional sharp tapered tip, HAR (High-Aspect-Ratio) shafts, small invasive surface area, and out-of-plane structure. In the skin test, the microneedle array penetrates back of the hand skin with minimum pain and without tip break and blood is drawn after puncturing the skin. Hot embossing process and mold fabrication process are also investigated with silicon and PDMS mold. The processed tetrahedral PMMA structures are fabricated into the microneedle array by the additional deep X-ray exposure. With these processes, the microneedle array can be utilized as the mold base for electroplating process.The author thanks the staff in 9 C LIGA beamline, Pohang Light Source (PLS), Korea for their assistance on the fabrication process. 相似文献
974.
An important issue in customer-oriented marketing area is target selection which enables the determination of potential customers. In this paper, we suggest a novel customer targeting method: customer map for a service industry. The customer map is the visualization method for customer targeting. It depicts value distribution across customer needs and customer characteristics. To develop the customer map, we integrate numerous customer data from various data sources, perform data analyses using data mining techniques, and finally visualize the information derived by the former analyses. The customer map helps decision makers to build customer-oriented strategy under the unified goal of customer targeting. It also affords to monitor and perceive real time state and the change of customer value distribution based on their information without preconception. We apply the customer map to a credit card company, build web-based prototype system for the customer map and acquire managerial implications from this study. 相似文献
975.
Ki‐Chan Lee Seung‐Hwan Moon Brian Berkeley Sang‐Soo Kim 《Journal of the Society for Information Display》2006,14(2):161-168
Abstract— Thin‐film‐transistor liquid‐crystal displays (TFT‐LCDs) have the largest market share of all digital flat‐panel displays. An LCD backlighting system employing a three‐color red‐green‐blue light‐emitting diode (RGB‐LED) array is very attractive, considering its wide color gamut, tunable white point, high dimming ratio, long lifetime, and environmental compatibility. But the high‐intensity LED has problems with thermal stability and degradation of brightness over time. Color and white luminance levels are not stable over a wide range of temperature due to inherent long‐term aging characteristics. In order to minimize color point and brightness differences over time, optical feedback control is the key technology for any LED‐backlight system. In this paper, the feasibility of an optical color‐sensing feedback system for an LED backlight by integrating the amorphous‐silicon (a‐Si) color sensor onto the LCD panel will be presented. To minimize the photoconductivity degradation of a‐Si, a new laser exposure treatment has been applied. The integrated color‐sensor optical‐feedback‐controlled LED‐backlight system minimized the color variation to less than 0.008 Δu'v' (CIE1976) compared to 0.025 for an open‐loop system over the temperature range of 42–76°C. 相似文献
976.
Two wideband tapered slot antennas are designed, fabricated, and tested. The first antenna, which is fabricated on a high dielectric constant substrate (?r = 10.2), shows a measured return loss of better than 10 dB from 1.6 to 12.4 GHz (7.7:1 bandwidth), and an antenna gain varying from 3.6 to 7.8 dBi. The second antenna is built on a low dielectric constant substrate (?r = 2.2), and demonstrates return loss of better than 10 dB from 1.8 to 15.2 GHz (8.4:1 bandwidth). The second antenna also has improved antenna gain, from 5 to 15.6 dBi, and is used to build a wideband 1 × 4 H‐plane phased array with a total gain of 9–17 dBi and a beam steering angle of ±15° from 3 to 12 GHz. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007. 相似文献
977.
When feature information is lost during a data transfer, the advantage of feature-based modeling becomes invalid. After that, even a small modification for a feature of the model becomes purely dependent on geometric and topological manipulations. The existing methods for the local modifications such as moving and tapering faces basically make use of ‘tweaking’, which is the technique to replace the surface of a face with different one. However, tweaking is limited to the modifications that do not involve topological changes in the model. Due to this limitation, tweaking does not work properly when local modifications involve topological changes. In this paper, a new volumetric method for the local modification for 3D CAD models is presented. This method can handle local modification involving topological changes by first separating the volume of feature from the model using the volume decomposition, and then uniting the modified feature with the model. 相似文献
978.
不完备条件下GPS定位算法的研究 总被引：3，自引：0，他引：3
利用全球定位系统（GPS）能在观测到3颗GPS卫星时实现2D定位,实现3D定位则需要至少观测到4颗卫星。在卫星观测数目为2或1的不完备条件下,仅利用GPS已无法完成正常定位。文章提出了结合数字地图的不完备条件下GPS定位算法,实验证明,应用该算法在仅能观测到2颗GPS卫星时能完成满足一定精度要求的定位,在仅能观测到1颗GPS卫星时能给出有价值的信息,并且能够简化地图匹配的工作,从而可以作为车载定位系统的有力补充。 相似文献
979.
通过对传统的下载过程进行分析和研究,提出一种新的Linux内核的自动下载方案。该方案采用有限状态机模型,自动控制Linux引导程序和内核的下载过程。经过编程实现和实际应用,该方案实现的下载工具能够快速、正确地对目标板进行下载Linux内核,提高了目标板下载的效率。 相似文献
980.
Sang Soo Kim Bong Hyun You Nam Deog Kim Brian H. Berkeley 《Journal of the Society for Information Display》2008,16(3):403-413
Abstract— Samsung has developed a high‐resolution full‐HD (1920 × 1080) 120‐Hz LCD‐TV panel using a novel pixel structure and a motion‐compensated frame‐interpolation (McFi) single‐chip solution. Our latest work includes launch of a 70‐in. full‐HD panel, the world's largest LCD TV in mass production, with a 120‐Hz frame rate. A serious problem involving the charging time margin has been completely overcome through the use of a new alternative 1G‐2D pixel structure and a new driving scheme. Compared with conventional dot‐inversion driving, our new dot‐inversion method, which is a spatial averaging technique, can save power because the column drivers are operated using vertical inversion driving. In addition, McFi, which merges individual ME/MC and timing‐controller (TCON) ICs and memories, has been developed and applied in a mass‐production product for the first time ever. The McFi solution provides 120‐Hz driving with the lowest possible system cost. Motion‐picture response time (MPRT) has been reduced from 1 5 to 8 msec. Moreover, for the case of 24‐Hz film source mode, motion judder has been completely eliminated. As a result, a lineup consisting of 40‐, 46‐, 52‐, 70‐, and 82‐in. LCD‐TV panels with high quality and manufacturability has been made possible. 相似文献