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101.
Mandarin fruit quality: a review   总被引:1,自引:0,他引:1  
During the last decade, there has been a continuous rise in consumption and global marketing of fresh, easy‐to‐peel mandarins, with current annual production of nearly 29 million tons. Nevertheless, most of the existing knowledge on quality traits of citrus fruit comes from research conducted on oranges and grapefruit, which are the main products for the citrus juice manufacturing industry; relatively little is yet known regarding the unique fruit quality traits of mandarins, nor about the great diversity in these traits among the various natural sub‐groups and varieties of mandarins. In the present review we discuss the physiological, biochemical, and molecular factors governing key fruit quality attributes of mandarins, including fruit colour, size and shape, ease of peeling, seedlessness, flavour, and nutritional quality. Fruit colour, size, and shape contribute to external appearance; peelability and seedlessness to ease of consumption; and flavour and nutritional quality to internal quality. © 2017 Society of Chemical Industry  相似文献   
102.
A metasurface hologram combines fine spatial resolution and large viewing angles with a planar form factor and compact size. However, it suffers coherent artifa...  相似文献   
103.
Documents are co-derivative if they share content: for two documents to be co-derived, some portion of one must be derived from the other, or some portion of both must be derived from a third document. An existing technique for concurrently detecting all co-derivatives in a collection is document fingerprinting, which matches documents based on the hash values of selected document subsequences, or chunks. Fingerprinting is hampered by an inability to accurately isolate information that is useful in identifying co-derivatives. In this paper we present spex, a novel hash-based algorithm for extracting duplicated chunks from a document collection. We discuss how information about shared chunks can be used for efficiently and reliably identifying co-derivative clusters, and describe deco, a prototype package that combines the spex algorithm with other optimisations and compressed indexing to produce a flexible and scalable co-derivative discovery system. Our experiments with multi-gigabyte document collections demonstrate the effectiveness of the approach.  相似文献   
104.
We introduce a novel pricing and resource allocation approach for batch jobs on cloud systems. In our economic model, users submit jobs with a value function that specifies willingness to pay as a function of job due dates. The cloud provider in response allocates a subset of these jobs, taking into advantage the flexibility of allocating resources to jobs in the cloud environment. Focusing on social-welfare as the system objective (especially relevant for private or in-house clouds), we construct a resource allocation algorithm which provides a small approximation factor that approaches 2 as the number of servers increases. An appealing property of our scheme is that jobs are allocated non-preemptively, i.e., jobs run in one shot without interruption. This property has practical significance, as it avoids significant network and storage resources for checkpointing. Based on this algorithm, we then design an efficient truthful-in-expectation mechanism, which significantly improves the running complexity of black-box reduction mechanisms that can be applied to the problem, thereby facilitating its implementation in real systems.  相似文献   
105.
We examine water desalination processes based on the electrosorption of ions onto activated carbon electrodes (capacitive deionization, CDI). A flow‐by operation mode was used (solutions flows within channels in the separator, parallel to the electrodes) in both continuous and stopped flow experiments. The different response of solutions containing more than 5000 ppm NaCl and dilute solutions (e.g., 1000 ppm NaCl) to the applied potential is discussed. The electrical current transients on potential steps were faster by two orders of magnitude than the resulting concentration transients due to the dynamics of these deionization processes and the properties of the cells used herein. Guidelines for the practical development of capacitive water deionization processes are discussed herein. It is assumed that for brackish water containing several thousands ppms of NaCl, CDI may be advantageous over competitive methods (e.g., reverse osmosis). © 2009 American Institute of Chemical Engineers AIChE J, 2010  相似文献   
106.
This article challenges Yaakov Kareev's (1995a, 2000) argument regarding the positive bias of intuitive correlation estimates due to working memory capacity limitations and its adaptive value (see record 1995-39555-001 and record 2000-15248-009). The authors show that, under narrow window theory's primacy effect assumption, there is a considerable between-individual variability of the effects of capacity limitations on the intuitive assessment of correlation, in terms of both sign and magnitude: Limited capacity acts as an amplifier for some individuals and as a silencer for others. Furthermore, the average amount of attenuation exceeds the average amount of amplification, and the more so, the smaller the capacity. Implications regarding the applicability and contribution of the bias notion in this context and the evaluation of the adaptive value of capacity limitations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.

Object

The aim of this work was to understand biophysical substrate underpinning contrast in diffusional kurtosis imaging (DKI) in white matter, using the composite hindered and restricted model of diffusion (CHARMED).

Materials and methods

A theoretical relationship between the kurtosis function K and the CHARMED parameters, i.e., the restricted volume fraction RF and the axonal longitudinal diffusivity D was derived for the propagator used in the CHARMED model. Evidence for a similar correlation between these measures was then investigated in vivo across different WM regions in five healthy young subjects that underwent a CHARMED protocol at 3T.

Results

Our theoretical treatment shows that K has an increasing trend for both increasing RF values and increasing D. In vivo, a significant positive correlation (P?K and RF. A multilinear regression showed that K values are better explained by a mixed contribution of both RF and D.

Conclusions

The CHARMED model was used to understand whether and where DKI contrast can be explained in terms of the underlying axonal geometry. This work demonstrates that the information contained in DKI overlaps with the information extracted by CHARMED in areas of higher intra-voxel directional coherence.  相似文献   
108.
Impressions for removable partial dentures (RPDs) should provide an accurate and detailed record of the teeth and soft tissues. Removable partial denture casts should be exact replicas of the mouth to ensure that RPD frameworks fit accurately and are fully adjusted to oral structures. A comparative clinical evaluation was performed on the oral fit of RPDs made from impressions with either irreversible hydrocolloid (alginate) or condensation silicone. The difference between the two groups was found to be statistically significant.  相似文献   
109.
The search for alternative energy sources is at the forefront of applied research. In this context, thermoelectricity, i.e., direct conversion of thermal into electrical energy, plays an important role, particularly for exploitation of waste heat. Materials for such applications should exhibit thermoelectric potential and mechanical stability. PbTe-based compounds include well-known n-type and p-type compounds for thermoelectric applications in the 50°C to 600°C temperature range. This paper is concerned with the mechanical and transport properties of p-type Pb0.5Sn0.5Te:Te and PbTe<Na> samples, both of which have a hole concentration of ∼1 × 1020 cm−3. The ZT values of PbTe<Na> were found to be higher than those of Pb0.5Sn0.5Te:Te, and they exhibited a maximal value of 0.8 compared with 0.5 for Pb0.5Sn0.5Te:Te at 450°C. However, the microhardness value of 49 HV found for Pb0.5Sn0.5Te:Te was closer to that of the mechanically stable n-type PbTe (30 HV) than to that of PbTe<Na> (71 HV). Thus, although lower ZT values were obtained, from a mechanical point of view Pb0.5Sn0.5Te:Te is preferable over PbTe<Na> for practical applications.  相似文献   
110.
Bug Attacks     
In this paper we present a new kind of cryptanalytic attack which utilizes bugs in the hardware implementation of computer instructions. The best-known example of such a bug is the Intel division bug, which resulted in slightly inaccurate results for extremely rare inputs. Whereas in most applications such bugs can be viewed as a minor nuisance, we show that in the case of RSA (even when protected by OAEP), Pohlig–Hellman and ElGamal encryption such bugs can be a security disaster: decrypting ciphertexts on any computer which multiplies even one pair of numbers incorrectly can lead to full leakage of the secret key, sometimes with a single well-chosen ciphertext. As shown by recent revelation of top secret NSA documents by Edward Snowden, intentional hardware modifications is a method that was used by the USA to weaken the security of commercial equipment sent to targeted organizations.  相似文献   
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