No description available.

It is well documented that urbanization changes the hydrology of watersheds (Hammer 1972; Booth 1991; Rose and Peters 2001). Increases in runoff volume and velocity from urbanization result in stream channel degradation (Hammer 1972; Henshaw and Booth 2000; Walsh et al. 2005; Leopold et al. 2005a; Poff et al. 2006). While stormwater management measures may be implemented to reduce the impact of stormwater runoff on streams, these practices do not reverse stream channel degradation that has already occurred. Stream restoration utilizing Natural Channel Stream Design (NCD) techniques is an effective way to reverse the effects of urbanization and return natural function to a stream. The design (bankfull) discharge for an NCD stream restoration project is the cornerstone of a restoration design. Existing methodologies for determining design discharges, such as hydrologic modeling and bankfull identification, have not worked well for NCD stream restoration projects in urban watersheds. The use of hydraulic geometry relationships serves as an alternative method for determining design discharge, but the required information is not generally available for urban Northern Virginia streams. However, rural regional curves developed for the Maryland piedmont, adjusted for watershed impervious area, provide a means to determine design discharges for urban stream restoration projects in Northern Virginia. / Master of Science

The optimum values for the section variables like channel side slope,bottom width,depth and radius for triangular,rectangular, trapezoidal and circular channels are computed by minimizing the cost of the channel section.Manning &rsquo / s uniform flow formula is treated as a constraint for the optimization model.The cost function is arranged to include the cost of lining,cost of earthwork and the increment in the cost of earthwork with the depth below the ground surface.The optimum values of section variables are expressed as simple functions of unit cost terms.Unique values of optimum section variables are obtained for the case of minimum area or minimum wetted perimeter problems.

Electroosmotic flow is widely used as a solution pumping method in numerous microfluidic applications. This type of flow has several advantages over other pumping techniques, such as the fast response time, the ease of control and integration in different microchannel designs. The flow utilizes the scaling of channel dimensions, which enhances the effects of the electrostatic forces to create flow in microchannels under an electrical body force. However, the electrostatic properties of the solution/wall material pairings are unique and must be experimentally measured. As a consequence, accurate knowledge about the electrostatic properties of the solution and wall material pairings is important for the optimal design of microfluidic devices using electroosmotic flow. Moreover, the introduction of new solutions and new channel materials for different applications is common in the microfluidics area. Therefore, any improvement on the experimental techniques used to examine the electrostatic properties of microchannels is beneficial to the research community. In this work, an improvement to the current-monitoring technique for studying the electrokinetic properties of microchannels is achieved by replacing the conventional straight channel design with a new Y-channel design. The errors from both the undesired pressure driven flow and solution electrolysis were addressed and significantly reduced. The new design offers high accuracy in finding the electrokinetic properties of microchannels. The experimental outcome from the new channel design is better compared to the outcomes of the straight channel, which helps in distinguishing the important electroosmotic pumping regions from the current-time plot. Moreover the time effectiveness in performing the experiments with the new channel design is better compared to that for the straight channel design. A modified analysis approach is also presented and validated for finding the electrokinetic properties from the outcomes of the current-monitoring technique, which is called the current-slope method. This approach is validated by comparing its findings with the results of the conventional length method. It was found for most situations that the discrepancy between the two methods, the current-slope and total length method, are within the uncertainty of the experimental measurements, thus validating the new analysis approach. In situations where it is hard to distinguish the start and end of solution replacement from the current-time plot of the current-monitoring technique, the current-slope method is advised. With the new design, different parametric studies of electroosmotic flow in PDMS based microchannels are estimated. At first the zeta potential of biological buffers are studied. Moreover the effect of continuous electroosmotic pumping, the chip substrate structure, and temperature on the average zeta potential of microchannels are examined. It was found that for air plasma treated PDMS microchannels the chip substrate material does not have an effect on the average zeta potential of the microchannels. The following chemical treatments are attempted with the aim of improving the surface and electrostatic properties of PDMS based microchannels: prepolymer additive with acrylic acid, extraction of PDMS, and both heat and plasma induced HEMA (Hydroxyethyl methacrylate) grafting on the surface of PDMS. Extensive characterization is performed with different experimental methods. The stability of the artificial hydrophilic properties of the PDMS microchannels with time was improved with both the extraction and HEMA grafting techniques. On the other hand, there was no evidence of any improvement in the zeta potential of microchannels with the surface treatments.

Electroosmotic flow is widely used as a solution pumping method in numerous microfluidic applications. This type of flow has several advantages over other pumping techniques, such as the fast response time, the ease of control and integration in different microchannel designs. The flow utilizes the scaling of channel dimensions, which enhances the effects of the electrostatic forces to create flow in microchannels under an electrical body force. However, the electrostatic properties of the solution/wall material pairings are unique and must be experimentally measured. As a consequence, accurate knowledge about the electrostatic properties of the solution and wall material pairings is important for the optimal design of microfluidic devices using electroosmotic flow. Moreover, the introduction of new solutions and new channel materials for different applications is common in the microfluidics area. Therefore, any improvement on the experimental techniques used to examine the electrostatic properties of microchannels is beneficial to the research community. In this work, an improvement to the current-monitoring technique for studying the electrokinetic properties of microchannels is achieved by replacing the conventional straight channel design with a new Y-channel design. The errors from both the undesired pressure driven flow and solution electrolysis were addressed and significantly reduced. The new design offers high accuracy in finding the electrokinetic properties of microchannels. The experimental outcome from the new channel design is better compared to the outcomes of the straight channel, which helps in distinguishing the important electroosmotic pumping regions from the current-time plot. Moreover the time effectiveness in performing the experiments with the new channel design is better compared to that for the straight channel design. A modified analysis approach is also presented and validated for finding the electrokinetic properties from the outcomes of the current-monitoring technique, which is called the current-slope method. This approach is validated by comparing its findings with the results of the conventional length method. It was found for most situations that the discrepancy between the two methods, the current-slope and total length method, are within the uncertainty of the experimental measurements, thus validating the new analysis approach. In situations where it is hard to distinguish the start and end of solution replacement from the current-time plot of the current-monitoring technique, the current-slope method is advised. With the new design, different parametric studies of electroosmotic flow in PDMS based microchannels are estimated. At first the zeta potential of biological buffers are studied. Moreover the effect of continuous electroosmotic pumping, the chip substrate structure, and temperature on the average zeta potential of microchannels are examined. It was found that for air plasma treated PDMS microchannels the chip substrate material does not have an effect on the average zeta potential of the microchannels. The following chemical treatments are attempted with the aim of improving the surface and electrostatic properties of PDMS based microchannels: prepolymer additive with acrylic acid, extraction of PDMS, and both heat and plasma induced HEMA (Hydroxyethyl methacrylate) grafting on the surface of PDMS. Extensive characterization is performed with different experimental methods. The stability of the artificial hydrophilic properties of the PDMS microchannels with time was improved with both the extraction and HEMA grafting techniques. On the other hand, there was no evidence of any improvement in the zeta potential of microchannels with the surface treatments.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19681号 / 工博第4136号 / 新制||工||1638(附属図書館) / 32717 / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 西脇 眞二, 教授 稲室 隆二, 教授 松原 厚 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21753号 / 工博第4570号 / 新制||工||1712(附属図書館) / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 西脇 眞二, 教授 松原 厚, 教授 黒瀬 良一 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

No description available.

中小企業相對國際企業缺乏資金、人才與經銷通路管理經驗，當進軍國際市場時，絕大部分依賴當地的中間商，因此，選擇合適的中間商是關鍵成功因素之一。 本研究以某台灣電腦機殼公司在北美洲為研究個案，該公司強調「以誠信為基礎的通路策略」與成為「通路掛帥」的公司為目標。本研究探討其進軍國際市場時的通路決策制定過程，其中企業目標與通路策略，對通路設計決策與通路管理有深度的影響力。 另通路結構的長度、寬度及密度是關鍵的策略意圖，足以影響未來通路運作的效率。在通路管理上，提供通路成員訓練、行銷宣傳支援、激勵方案、績效評估等來協助通路成員達成預期的目標。 此外，面對外在經營環境變化與內在營運模式的調整，個案公司採用選擇性通路，以降低通路衝突的機率並提升通路效力。公司在調整通路結構時，改變通路成員的質與量，以達到地理區域的涵蓋度與深耕特定目標市場的目的。同時並採用「與巨人共舞，以小博大」的通路策略，對於選定的少數且極其重要的通路成員採取「深耕、做大」策略。研究中發現大型經銷通路商對於「以誠信為基礎的通路策略」比較認同，且對於個案公司建立通路管理制度的要求全力配合，其通路績效更佳。 最後提出對個案公司的建議: 1.高階主管需參與執行並貫徹「以誠信為基礎的行銷通路策略」。 2.面對快速變遷的外在環境與市場競爭情境，策略的生命週期變短，公司必需隨時檢視、修正或調整國際通路策略。 3.透過企業內部教育訓練，培養高階主管與資深團隊的通路管理能力。 4.台灣總公司OEM/ODM業務與北美全球性經銷商的衝突，亟需建立溝通協調與管控機制。 / Small- and medium-sized enterprises (SMEs), in contrast to large multinational corporations, often lack the financial resources, exposure, and expertise in product distribution channel management. When entering a foreign market, SMEs often have to rely heavily on channel partners. Consequently, selecting the appropriate channel partners is one of the key success factors in channel management. This study examined a medium-sized Taiwanese PC enclosure company as it sought to expand in the North American market. To this end, the company adopted an integrity-based channel management strategy and strived to become a channel champion. The internal decision-making processes for channel partner selection were outlined and the influences of the company objectives on its channel design were analyzed. Furthermore, considerations on the length, width, and density – three important factors to an efficient channel strategy – were introduced. Lastly, methods to support channel partners in the form of product training, marketing and promotional support, incentive programs, and an appropriate performance appraisal system were discussed. To maximize channel efficiency and reduce potential conflicts between channel partners, the company employed a tiered channel strategy. Extending the geographic coverage and penetrating key select markets was achieved by carefully selecting channel partners after weighing in the quality of their downstream distribution channels and their sales volume. Revenue growth in select markets was achieved by leveraging the strengths of a few competent channel partners. These channel partners have subsequently recognized the benefits of the integrity-based channel management strategy and are more committed to fulfilling their roles within the overall auspices of the channel distribution system. Recommendations to the company based on the research findings are the following: 1.The management should be involved and be committed to the implementation of the integrity-based channel management strategy. 2.In the face of constant changes in the business environment, channel strategy should be reviewed and revised anytime. 3.Internal training to senior management to raise their capability of channel stewardship. 4.Establish a mechanism to resolve potential conflicts between Taiwanese OEM/ODM sales team and channel partners in North America.

The thesis is concerned with the design of a flood protection for the Brantice municipality, a part of which is an adjustment of the Opava river stream bed, specifically kilometer 77,6554 to 78,7020 and, moreover, a design of a reconstruction of the weir at kilometer 78,340. A capacity assessment of the original stream bed in the built-up area and its surroundings is a part of the thesis, as well as a measure to increase the stream capacity and a design of a boulder chute with a water gate, which replaced the original weir. The program HEC-RAS 4.1.0. was used for the stream capacity calculations.