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1.
With the emergence of distributed ledger technology (DLT), numerous practitioners and researchers have proclaimed its beneficial impact on supply chain transactions in the future. However, the vast majority of DLT initiatives are discontinued after a short period. With the full potential of DLT laying far down the road, especially managers in supply chain management (SCM) seek for short-term cost-saving effects of DLT in order to achieve long-term benefits of DLT in the future. However, the extant research has bypassed grounding long-term as well as short-term effects of DLT on supply chain transaction with empirical data. We address this shortcoming, following an abductive research approach and combining empirical data from a multiple case study design with the corresponding literature. Our study reveals that the effects of DLT on supply chain transactions are two-sided. We found six effects of DLT solutions that have a cost-reducing or cost avoidance impact on supply chain transactions. In addition, we found two effects that change the power distribution between buyers and suppliers in transactions and a single effect that reduces the dependency of supply chain transactions on third parties. While cost-reducing and avoidance as well as dependency-reducing effects are positive effects, the change in power distribution might come with disadvantages. With these findings, the paper provides the first empirical evidence of the impact of DLT on supply chain transactions, which will enable managers to improve their assessment of DLT usage in supply chains.  相似文献   
2.
To quantify the evacuation process, evacuation practitioners use engineering egress data describing the occupant movement characteristics. These data are typically based to young and fit populations. However, the movement abilities of occupants who might be involved in evacuations are becoming more variable—with the building populations of today typically including increasing numbers of individuals: with impairments or who are otherwise elderly or generally less mobile. Thus, there will be an increasing proportion of building occupants with reduced ability to egress. For safe evacuation, there is therefore a need to provide valid engineering egress data considering pedestrians with disabilities. Gwynne and Boyce recently compiled a series of data sets related to the evacuation process to support practitioner activities in the chapter Engineering Data in the SFPE Handbook of Fire Protection Engineering. This paper supplements these data sets by providing information on and presenting data obtained from additional research related to the premovement and horizontal movement of participants with physical‐, cognitive‐, or age‐related disabilities. The aim is to provide an overview of currently available data sets related to, and key factors affecting the egress performance of, mixed ability populations which could be used to guide fire safety engineering decisions in the context of building design.  相似文献   
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An addition of boron largely increases the ductility in polycrystalline high-temperature Co–Re alloys. Therefore, the effect of boron on the alloy structural characteristics is of high importance for the stability of the matrix at operational temperatures. Volume fractions of ε (hexagonal close-packed—hcp), γ (face-centered cubic—fcc) and σ (Cr2Re3 type) phases were measured at ambient and high temperatures (up to 1500 °C) for a boron-containing Co–17Re–23Cr alloy using neutron diffraction. The matrix phase undergoes an allotropic transformation from ε to γ structure at high temperatures, similar to pure cobalt and to the previously investigated, more complex Co–17Re–23Cr–1.2Ta–2.6C alloy. It was determined in this study that the transformation temperature depends on the boron content (0–1000 wt. ppm). Nevertheless, the transformation temperature did not change monotonically with the increase in the boron content but reached a minimum at approximately 200 ppm of boron. A probable reason is the interplay between the amount of boron in the matrix and the amount of σ phase, which binds hcp-stabilizing elements (Cr and Re). Moreover, borides were identified in alloys with high boron content.  相似文献   
5.
The synthesis of powders with controlled shape and narrow particle size distributions is still a major challenge for many industries. A continuous Segmented Flow Tubular Reactor (SFTR) has been developed to overcome homogeneity and scale‐up problems encountered when using batch reactors. Supersaturation is created by mixing the co‐reactants in a micromixer inducing precipitation; the suspension is then segmented into identical micro‐volumes by a non‐miscible fluid and sent through a tube. These micro‐volumes are more homogeneous when compared to large batch reactors leading to narrower size distributions, better particle morphology, polymorph selectivity and stoichiometry. All these features have been demonstrated on single tube SFTR for different chemical systems. To increase productivity for commercial application the SFTR is being “scaled‐out” by multiplying the number of tubes running in parallel instead of scaling‐up by increasing their size. The versatility of the multi‐tube unit will allow changes in type of precipitate with a minimum of new investment as new chemistry can be researched, developed and optimised in a single tube SFTR and then transferred to the multi‐tube unit for powder production.  相似文献   
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In rhodopsin, the 11-cis-retinal chromophore forms a complex with Lys296 of opsin via a protonated Schiff base. Absorption of light initiates the activation of rhodopsin by cis/trans photoisomerization of retinal. Thermal relaxation through different intermediates leads into the metarhodopsin states which bind and activate transducin (Gt) and rhodopsin kinase (RK). all-trans-Retinal also recombines with opsin independent of light, forming activating species of the receptor. In this study, we examined the mechanism by which all-trans-retinal activates opsin. To exclude other amines except active site Lys296 from formation of Schiff bases, we reductively methylated rhodopsin (PM-rhodopsin), which we then bleached to generate PM-opsin. Using spectroscopic methods and a Gt activation assay, we found that all-trans-retinal interacted with PM-opsin, producing a noncovalent complex that activated Gt. The residual nucleotide exchange in Gt catalyzed by opsin was approximately 1/250 lower relative to that of photoactivated rhodopsin (pH 8.0, 23 degrees C). Addition of equimolar all-trans-retinal led to an occupancy of one-tenth of the putative retinal binding site(s) of opsin and enhanced the Gt activation rate 2-fold. When the concentration of all-trans-retinal was increased to saturation, the Gt activation rate of the opsin/all-trans-retinal complex was approximately 1/33 lower compared to that of photoactivated rhodopsin. We conclude that all-trans-retinal can form a noncovalent complex with opsin that activates Gt by different mechanisms than photolyzed rhodopsin.  相似文献   
8.
Types of crystallizers . In the industrial application of single mass crystallization from solution clear aims exist with regard to crystallizate qualities. To fulfil these aims, one can choose between various types of crystallizers. Magma types, i.e. agitated tank crystallizer, forced circulation and draft tube (baffle) crystallizer, as well as classifying types with the well-known Oslo-crystallizer belong to the present state of the art. The rates of secondary nucleation decrease in the same sequence as that given above and the possibilities of influencing crystal size distributions increase, and coarser crystals are produceable.  相似文献   
9.
Although principal component analysis (PCA) is an important tool in standard multivariate data analysis, little interest has been devoted to assessing whether the underlying relationship within a given variable set can be described by a linear PCA model or whether nonlinear PCA must be utilized. This paper addresses this deficiency by introducing a nonlinearity measure for principal component models. The measure is based on the following two principles: (i) the range of recorded process operation is divided into smaller regions; and (ii) accuracy bounds are determined for the sum of the discarded eigenvalues. If this sum is within the accuracy bounds for each region, the process is assumed to be linear and vice versa. This procedure is automated through the use of cross-validation. Finally, the paper shows the utility of the new nonlinearity measure using two simulation studies and with data from an industrial melter process.  相似文献   
10.
第1部分射频系统级封装(RF SiP,RF System-in-Pack-age)技术是一种对无线通信非常有用的封装平台,无线通信被如下事实所困,但由于目前SiP设计仍  相似文献   
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