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11.
Alexander E. Ellinger Daniel F. Lynch James K. Andzulis Ronn J. Smith 《Journal of Business Logistics》2003,24(1):199-220
An Internet presence is a critical early component in the process of building towards a fully operational and unified e‐commerce strategy. E‐commerce has significantly impacted logistics/supply chain strategies and the development and implementation of a website have become key issues for many firms within the transportation industry. This study provides an overview of website content within the motor carrier industry. Content analysis was used to assess the site design, informational content, and the interactive content of 152 motor carrier websites, and to compare the features offered on the Top 100 motor carrier firm websites with those offered on the sites of smaller carrier firms. 相似文献
12.
Alexander Maedche 《International Journal of Intelligent Systems in Accounting, Finance & Management》2004,12(3):215-225
Bringing knowledge management to practice one typically has to focus on concrete problems that exist in the daily work of the knowledge worker. We consider the task of tracking relevant information on the Web as important and time consuming, and thus as a concrete problem. In this paper we introduce an integrated approach for Web information tracking using ontologies. The overall approach has been implemented within a case study carried out at DaimlerChrysler AG. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
13.
Steven B. Kuzyk Alexander O. Pritchard Jocelyn Plouffe John L. Sorensen Vladimir Yurkov 《Journal of Great Lakes research》2021,47(3):715-724
Violet and purple bacterial pigmentations are uncommon when considering strict aerobes. Here we report discovery of two novel isolates, P102 and P117 from the freshwater Lake Winnipeg, each with violet to deep purple colony colouration. The relationship between pigment production and growth was investigated under different conditions, including a variety of carbon sources, pH, and temperatures. The violet compounds were purified using polar organic solvents, and then structurally characterized via mass spectrometry and nuclear magnetic resonance to be violacein and deoxyviolacein. Strain P117 produced higher concentrations of the darker pigment deoxyviolacein, which resulted in a deeper hue of violet than in cultures of P102. Strain P102, synthesized violacein maximally in liquid rich organic medium at pH 8 and 20 °C, and had 99.3% sequence similarity to the 16S rDNA from Janthinobacterium lividum. Strain P117, related to Massilia violaceinigra sharing 99.2% 16S rDNA sequence similarity, also produced violacein at similar optimal conditions, but developed higher concentrations of pigment at 15 °C. Culture-based methods found that violacein producers composed 0.001% or 0.023% CFU of environmental heterotrophic populations using BG-11 and potato-based media, respectively. Culture-independent high-throughput ribosomal 16S V4 sequencing of environmental DNA was used to detect Gram-negative species known for their production of violacein. Of all bacterial and archaeal sequences present during the fall in littoral waters and sediment of Lake Winnipeg, 5.5% and 6.3%, respectively, belonged to species that have similar pigment, demonstrating the scarcity of violacein producers in this aquatic freshwater system. 相似文献
14.
Alexander Gatch Dimitry Gorsky Zy Biesinger Eric Bruestle Kelley Lee Curt Karboski Meredith L. Bartron Tyler Wagner 《Journal of Great Lakes research》2021,47(2):486-493
Restoration of a wild-produced lake trout Salvelinus namaycush population in Lake Ontario has not been successful despite the adult population often meeting or exceeding restoration targets. Lack of high-quality spawning habitat in Lake Ontario is suggested as one impediment to recruitment of wild lake trout, although the quantity and location of spawning habitat is poorly understood. If high-quality spawning habitat is limited in Lake Ontario, lake trout may be using uncommon spawning locations such as rivers. Anecdotal angler accounts point to the Niagara River as a lake trout spawning location. To better understand the potential of the Niagara River as a spawning location, egg and juvenile fish collections were conducted 12–14 river kilometers from the mouth of the Niagara River from 2010 to 2012; and mature female lake trout with surgically implanted acoustic tags were monitored from 2015 to 2019. Genetic analyses confirmed 60% of collected eggs and 93% of collected post-hatch juvenile fish in the Niagara River were lake trout. Tagged female lake trout returned to the Niagara River over consecutive years during the spawning season. The short duration of lake trout presence in the river (mean = 56 days/year) suggests female lake trout use the Niagara River primarily for spawning. Diversity in spawning locations may provide lake trout population’s resilience against environmental variability through a portfolio effect. Improved identification of riverine spawning locations, including their overall contribution to wild recruitment, may be a useful tool for managers to restore a wild-produced population of lake trout in Lake Ontario. 相似文献
15.
John C. Alexander Jr. Michael F. Spivey 《The Quarterly Review of Economics and Finance》1997,37(4):905-921
The Worker Adjustment and Retraining Notification (WARN) Act of 1989 mandated that at least 60 days advance notice be given to employees. Critics argued that its passage would decrease managerial flexibility in closing plants, subsequently reducing firm values. This study addresses this issue by examining the stock market's reaction to announcements leading to the eventual enactment of the WARN legislation. We find evidence indicating negative effects of the legislation on stock returns of small firms. 相似文献
16.
Alexander Zaigraev 《Metrika》2002,56(3):259-273
Within the framework of classical linear regression model optimal design criteria of stochastic nature are considered. The particular attention is paid to the shape criterion. Also its limit behaviour is established which generalizes that of the distance stochastic optimality criterion. Examples of the limit maximin criterion are considered and optimal designs for the line fit model are found. 相似文献
17.
Maziar Gholami Korzani Sergio A. Galindo-Torres Alexander Scheuermann David J. Williams 《水科学与水工程》2017,10(2):143-153
Simulations of two-dimensional (2D) flow past a circular cylinder with the smoothed particle hydrodynamics (SPH) method were conducted in order to accurately determine the drag coefficient. The fluid was modeled as a viscous liquid with weak compressibility. Boundary conditions, such as a no-slip solid wall, inflow and outflow, and periodic boundaries, were employed to resemble the physical problem. A sensitivity analysis, which has been rarely addressed in previous studies, was conducted on several SPH parameters. Hence, the effects of distinct parameters, such as the kernel choices and the domain dimensions, were investigated with the goal of obtaining highly accurate results. A range of Reynolds numbers (1–500) was simulated, and the results were compared with existing experimental data. It was observed that the domain dimensions and the resolution of SPH particles, in comparison to the obstacle size, affected the obtained drag coefficient significantly. Other parameters, such as the background pressure, influenced the transient condition, but did not influence the steady state at which the drag coefficient was determined. 相似文献
18.
Alexander Matros 《Journal of Economic Theory》2003,111(1):110-124
Saez-Marti and Weibull (J. Econom. Theory 86 (1999) 268) investigate the consequences of letting some agents play a myopic best reply to the myopic best reply in Young's (J. Econom. Theory 59 (1993) 145) bargaining model, which is how they introduce “cleverness” of players. I analyze such clever agents in general finite two-player games and show Young's (Individual Strategy and Social Structure, Princeton University Press, Princeton, NJ, 1998) prediction to be robust: adaptive learning with clever agents does select the same minimal curb set as in the absence of clever agents, if their population share is less than one. However, the long-run strategy distribution in such a curb set may vary with the share of clever agents. 相似文献
19.
The determination of interconnection charges to essential facilities is an important problem in regulated telecommunications markets in the wake of the Telecommunications Act of 1996. This paper defines mathematical conditions for the essentiality of upstream productive inputs and examines their implications for efficient interconnection pricing. The paper shows conditions under which the efficient component-pricing rule (ECPR) can be derived as a special case of a Ramsey pricing rule. The paper also shows how efficient pricing differs from the ECPR for a number of interesting cases. 相似文献
20.
Abstract . Today's conventional economics typically ignores the impact of alternative forms of work organization upon the welfare of the worker. In effect, its methodology is concerned with the welfare of the individual as a consumer, but not with the welfare of the individual as a worker. Hence, welfare conclusions of economics are subject to challenge on grounds of being incomplete. Whether the worker is alienated or achieves self-fulfillment, etc., stands in no necessary relationship to either the formal lines of enterprise ownership, political ideology or form of economic system. Questions of authority and power in work organizations and the workplace conditions affecting the worker on the job transcend them. 相似文献