Freshdirect: Expansion Strategy

2006 ◽  
Author(s):  
Timothy M. Laseter ◽  
Debashish Chatterjee
Keyword(s):  
2019 ◽  
Author(s):  
KAIKAI MA ◽  
Peng Li ◽  
John Xin ◽  
Yongwei Chen ◽  
Zhijie Chen ◽  
...  

Creating crystalline porous materials with large pores is typically challenging due to undesired interpen-etration, staggered stacking, or weakened framework stability. Here, we report a pore size expansion strategy by self-recognizing π-π stacking interactions in a series of two-dimensional (2D) hydrogen–bonded organic frameworks (HOFs), HOF-10x (x=0,1,2), self-assembled from pyrene-based tectons with systematic elongation of π-conjugated molecular arms. This strategy successfully avoids interpene-tration or staggered stacking and expands the pore size of HOF materials to access mesoporous HOF-102, which features a surface area of ~ 2,500 m2/g and the largest pore volume (1.3 cm3/g) to date among all reported HOFs. More importantly, HOF-102 shows significantly enhanced thermal and chemical stability as evidenced by powder x-ray diffraction and N2 isotherms after treatments in chal-lenging conditions. Such stability enables the adsorption of dyes and cytochrome c from aqueous media by HOF-102 and affords a processible HOF-102/fiber composite for the efficient photochemical detox-ification of a mustard gas simulant.


Author(s):  
Matthias Heitmann ◽  
Thomas Huhn ◽  
Stefan Sievers ◽  
Gerhard Schembecker ◽  
Christian Bramsiepe

Author(s):  
W. H. Jonathan Mak ◽  
Michel-Alexandre Cardin ◽  
Liu Ziqi ◽  
P. John Clarkson

The concept of resilience has emerged from various domains to address how systems, people and organizations can handle uncertainty. This paper presents a method to improve the resilience of an engineering system by maximizing the system economic lifecycle value, as measured by Net Present Value, under uncertainty. The method is applied to a Waste-to-Energy system based in Singapore and the impact of combining robust and flexible design strategies to improve resilience are discussed. Robust strategies involve optimizing the initial capacity of the system while Bayesian Networks are implemented to choose the flexible expansion strategy that should be deployed given the current observations of demand uncertainties. The Bayesian Network shows promise and should be considered further where decisions are more complex. Resilience is further assessed by varying the volatility of the stochastic demand in the simulation. Increasing volatility generally made the system perform worse since not all demand could be converted to revenue due to capacity constraints. Flexibility shows increased value compared to a fixed design. However, when the system is allowed to upgrade too often, the costs of implementation negates the revenue increase. The better design is to have a high initial capacity, such that there is less restriction on the demand with two or three expansions.


Author(s):  
C Tyler Dick ◽  
Ivan Atanassov ◽  
F Bradford Kippen ◽  
Darkhan Mussanov

Distributed power locomotives have facilitated longer heavy-haul freight trains that improve the efficiency of railway operations. In North America, where the majority of mainlines are single track, the potential operational and economic advantages of long trains are limited by the inadequate length of many existing passing sidings (passing loops). To alleviate the challenge of operating trains that exceed the length of passing sidings, railways preserve the mainline capacity by extending passing sidings. However, industry practitioners rarely optimize the extent of infrastructure investment for the volume of over-length train traffic on a particular route. This paper investigates how different combinations of normal and over-length trains, and their relative lengths, relate to the number of siding extensions necessary to mitigate the delay performance of over-length train operation on a single-track rail corridor. The experiments used Rail Traffic Controller simulation software to determine train delay for various combinations of short and long train lengths under different directional distributions of a given daily railcar throughput volume. Simulation results suggest a relationship between the ratio of train lengths and the infrastructure expansion required to eliminate the delay introduced by operating over-length trains on the initial route. Over-length trains exhibit delay benefits from siding extensions while short trains are relatively insensitive to the expanded infrastructure. Assigning directional preference to over-length trains improves the overall average long-train delay at the expense of delay to short trains. These results will allow railway practitioners to make more informed decisions on the optimal incremental capital expansion strategy for the operation of over-length trains.


2018 ◽  
Vol 59 (8) ◽  
pp. 1630-1666 ◽  
Author(s):  
Nathaniel C. Lupton ◽  
Guoliang Frank Jiang ◽  
Luis F. Escobar ◽  
Alfredo Jiménez

We examine the extent to which host country income inequality influences multinational enterprises’ (MNE) expansion strategy for foreign production investment, depending on their specific strategic objectives. Applying a transaction cost framework, we predict that national income inequality has an inverted U-shaped relationship with foreign production investment. As inequality increases, MNEs accrue lower transaction costs arising from interactions with various local actors, leading to higher probability of investment. As income inequality increases further, its effect on location attractiveness will become negative, as its attraction effect is increasingly offset by additional monitoring, bargaining, and security costs owing to the more fractious nature of high inequality societies. In addition, we suggest that the impact of income inequality is contingent on investment objectives: The inverted U-shaped relationship is stronger for efficiency-seeking investment but weaker for market-seeking and competence-enhancing investments. We find substantial support for our hypotheses through an analysis of 27 years (1986-2012) of data on Japanese MNEs’ overseas production entries.


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