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排序方式: 共有1204条查询结果,搜索用时 15 毫秒
1.
Cheng-Hsiung Lid Shou-Chiung Chen Yung-Chi Lee Theodore D. Sokoloski Ming-Thau Sheu 《Drug development and industrial pharmacy》1994,20(11):1911-1922
Polyvinylpyrrolidone (PVP) in aqueous solution was used as a binding agent in a fluidized-bed system to agglomerate acetaminophen powder into directly compressible granules. It was found that a minimal amount of 5% w/w PVP in a concentration of 7.5% w/v or less was needed to produce granules with an acceptable flow and the corresponding tablets having enough hardness without capping. There was a strong correlation between the time for 80% dissolved (T80) and the logarithm of granule volume-surface mean diameter. A directly compressible acetaminophen composition to manufacture tablets having a T80 value less than 30 min can be prepared simply by adding an appropriate amount of disintegrant (crospovidone, sodium starch glycolate, or pregelatinized starch) to the agglomerated granules. 相似文献
2.
By using the arterial and venous phases of an anterior cerebral perfusion study, which showed downward displacement of the sagittal sinus, and the finding of a "rim" on the delayed scans, the specific diagnosis of epidural hematoma was established. 相似文献
3.
Yoshihisa Kosugi Masato Goto Zhenhong Tan Asaya Fujita Takashi Saito Takashi Kamiyama Wei-Tin Chen Yu-Chun Chuang Hwo-Shuenn Sheu Daisuke Kan Yuichi Shimakawa 《Advanced functional materials》2021,31(25):2009476
Materials which show novel thermal properties can be used to make highly efficient and environmentally friendly energy systems for thermal energy storage and refrigeration through caloric effects. An A-site-ordered quadruple perovskite-structure oxide, NdCu3Fe4O12, is found to release significant latent heat, 25.5 kJ kg−1 (157 J cc−1), at the intersite-charge-transfer transition temperature near room temperature. The transition is first-order and accompanied by an unusual magnetic ordering and a large negative-thermal-expansion-like volume change, and thus, it causes a large entropy change (84.2 J K−1 kg−1). The observed entropy change is comparable to the largest changes reported in inorganic solid materials, and more importantly, it is utilized through a colossal barocaloric effect. The adiabatic temperature change by applying 5.1 kbar pressure is estimated to reach 13.7 K, which means efficient refrigeration can be realized through this effect. 相似文献
4.
Shey-Huei Sheu 《Microelectronics Reliability》1992,32(5)
A system is subject to shocks that arrive according to a nonhomogeneous Poisson process. The system is replaced at age T at a fixed cost c0. If the k-th shock arrives at time Sk<T, it is either a fatal shock with probability p(Sk) or a nonfatal shock with probability 1−p(Sk). The fatal shock causes the system total breakdown, and the system is replacd at a cost c∞. The nonfatal shock weakens the system and makes it more expensive to run. The aim of the paper is to find the optimal T which minimizes the long run expected cost per unit time of the policy. Various special cases are considered. 相似文献
5.
Nitride-Based ultraviolet metal-semiconductor-metal photodetectors with a low-temperature GaN layer 总被引:1,自引:0,他引:1
J. K. Sheu C. J. Kao M. L. Lee W. C. Lai L. S. Yeh G. C. Chi S. J. Chang Y. K. Su J. M. Tsai 《Journal of Electronic Materials》2003,32(5):400-402
The GaN metal-semiconductor-metal (MSM) ultraviolet (UV) photodetectors with a low-temperature (LT)-GaN layer have been demonstrated.
It was found that we could achieve a two orders of magnitude smaller, photodetector-dark current by introducing a LT-GaN layer,
which could be attributed to the larger Schottky-barrier height between the Ni/Au metal contact and the LT-GaN layer. It was
also found that photodetectors with the LT-GaN layer could provide a larger photocurrent to dark-current contrast ratio and
a larger UV-to-visible rejection ratio. The maximum responsivity was found to be 3.3 A/W and 0.13 A/W when the photodetector
with a LT-GaN layer was biased at 5 V and 1 V, respectively. 相似文献
6.
In wireless sensor networks, query execution over a specific geographical region is an essential function for collecting sensed
data. However, sensor nodes deployed in sensor networks have limited battery power. Hence, the minimum number of connected
sensor nodes that covers the queried region in a sensor network must be determined. This paper proposes an efficient distributed
protocol to find a subset of connected sensor nodes to cover the queried region. Each node determines whether to be a sensing node to sense the queried region according to its priority. The proposed protocol can efficiently construct a subset of connected
sensing nodes and respond the query request to the sink node. In addition, the proposed protocol is extended to solve the k-coverage request. Simulation results show that our protocol is more efficient and has a lower communication overhead than
the existing protocol. 相似文献
7.
Shey-Huei Sheu 《Microelectronics Reliability》1991,31(5)
A policy of periodic replacement with minimal repair at failure is considered for the multi-unit system which have the specific multivariate distribution. Under such a policy an operating system is completely replaced whenever it reaches age T (T > 0) at a cost c0 while minimal repair is performed at any intervening component failures. The cost of the j-th minimal repair to the component which fails at age y is g(C(y),cj(y)), where C(y) is the age-dependent random part, cj(y) is the deterministic part which depends on the age and the number of the minimal repair to the component, and g is an positive nondecreasing continuous function. A simple expression is derived for the expected minimal repair cost in an interval in terms of the cost function and the failure rate of the component. Necessary and sufficient conditions for the existence of an optimal replacement interval are exhibited. 相似文献
8.
In recent years, we can easily observe that animations, comics, and games (ACG) have great output value and market influence on the entertainment and digit media market. The ACG industry is not an industry of a single country or region but a global industry. In addition to its own revenue, the derivative products (or licensed merchandise) of ACG can extend the ACG industry to win more business opportunities. The ACG industry is mainly marketed towards younger people, who are the major users of social network sites. Hence, the electronic word-of-mouth (eWOM) on social network sites often becomes a reference basis of the young people’s attitudinal acceptance and purchase intention in purchasing ACG-related derivative product.In this paper, we analyze the influential factors of positive eWOM’s communication motivations that affect consumer acceptance on social network sites, and apply the uncomplicated decision tree data mining algorithm to compute the association rules between these influential factors and consumer acceptance, expecting to understand the relationship between eWOM on social network sites and consumer acceptance. The results of this study can help the business decision-making in CRM and marketing of the industry of ACG-related derivative product. This study found that the degree of perception of ACG product and the degree of taking pleasure in sharing ACG-related information with others have a significant correlation with consumer acceptance. 相似文献
9.
Among the entertainment and media market, it can be observed that animations, comics, and video games (hereinafter abbreviated as ACG) have the highest output value and most market influence. Moreover, ACG also incorporates various industries and creates many derivative products. As the ACG industry emphasizes acousto-optics, imagery, and storylines, personal impressions derived from consumer experiences will influence consumer decisions. In addition, the ACG industry is mainly marketed towards younger age groups, with younger people being the main consumers; as such, these consumers’ decisions are more easily affected by peer behavior.This study aims to analyze the effects of internal cognitions and external influences on buying behavior of ACG consumers by applying the uncomplicated decision tree data mining algorithm. We analyze and develop the target attributes on measures of customer loyalty for ACG industry to set up the decision trees from the collected questionnaire data. The decision tree data mining method is applied to analyze the hidden association rules between the target attributes (i.e., consumer loyalty) and the critical influencing factors of consumer’s internal impressions and external influences for ACG consumers. The results and suggestions of this paper can be used as a reference for enterprises in the ACG industry to help with business policies concerning products’ extensional design, marketing, and CRM, and to further strengthen customer satisfaction and loyalty, thus increasing company profits. 相似文献
10.
A Distributed Localization Scheme for Wireless Sensor Networks with Improved Grid-Scan and Vector-Based Refinement 总被引:2,自引:0,他引:2
Jang-Ping Sheu Pei-Chun Chen Chih-Shun Hsu 《Mobile Computing, IEEE Transactions on》2008,7(9):1110-1123
Localization is a fundamental and essential issue for wireless sensor networks (WSNs). Existing localization algorithms can be categorized as either range-based or range-free schemes. Range-based schemes are not suitable for WSNs because of their irregularity of radio propagation and their cost of additional devices. In contrast, range-free schemes do not need to use received signal strength to estimate distances and only need simple and cheap hardware, and are thus more suitable for WSNs. However, existing range-free schemes are too costly and not accurate enough or are not scalable. To improve previous work, we present a fully distributed range-free localization scheme for WSNs. We assume that only a few sensor nodes, called anchors, know their locations, and the remaining (normal) nodes need to estimate their own locations by gathering nearby neighboring information. We propose an improved grid-scan algorithm to find the estimated locations of the normal nodes. Furthermore, we derive a vector-based refinement scheme to improve the accuracy of the estimated locations. Analysis, simulation, and experiment results show that our scheme outperforms the other range-free schemes even when the communication radius is irregular. 相似文献