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For applications, having efficient modules with a large active area is paramount. In this work, two series of anthryl dyes were synthesized to study their fundamental properties and photovoltaic pe...

A series of tailor-made highly efficient and near-infrared (NIR) porphyrin-based acceptors is designed and synthesized for fullerene-free bulk-heterojunction (BHJ) organic solar cells. Constructing BHJ active layers using a PTB7-Th donor and porphyrin acceptors (P-x), which have complementary absorption, accomplishes panchromatic photon-to-current conversion from 300 to 950 nm. Our study shows that side chains of the porphyrin acceptors fairly influence the molecular ordering and nanomorphology of the BHJ active layers. Significantly, the porphyrin acceptor with four dodecoxyl side chains (P-2) achieves an open-circuit voltage (VOC) of 0.80 V, short-circuit current density (JSC) of 13.94 mA cm-2, fill factor of 64.8%, and overall power conversion efficiency of 7.23%. This great performance is attributable to the ascendant light-harvesting capability in the visible and near-infrared region, a high-lying LUMO energy level, a relatively high and more balanced carrier mobilities, and more ordered face-on molecular packing, which is beneficial for obtaining high VOC and JSC.

The outbreak of COVID-19 around the world has caused great damage to the global economy. The tourism industry is among the worst-hit industries. How to focus on visitors who are most helpful to the tourism industry and develop sustainable strategy of operation is a very important question for after the epidemic is over. This study applied two-stage data envelopment analysis (DEA) and principal component analysis (PCA) to investigate past statistics from the Tourism Bureau and explore the shopping patterns of tourists who travel to Taiwan. The focus will be on tourists from major countries such as China, Japan, and Southeast Asian countries. According to the analysis of tourists from different countries, the money spent by tourists from different countries is concentrated on different items, and there are subitems that they particularly like to purchase. For the analysis of the purpose of coming to Taiwan, some tourism areas worth developing (such as medical treatment and leisure) are also presented in the research results. Based on these results, and according to the sustainable development goals, specific recommendations for the sustainability strategy of operation are made as a reference for the government and relevant industries. This research also broadens the scope of application of DEA and points out a different direction for future research.

Deep learning technology is widely used in medicine. The automation of medical image classification and segmentation is essential and inevitable. This study proposes a transfer learning–based kidney segmentation model with an encoder–decoder architecture. Transfer learning was introduced through the utilization of the parameters from other organ segmentation models as the initial input parameters. The results indicated that the transfer learning–based method outperforms the single-organ segmentation model. Experiments with different encoders, such as ResNet-50 and VGG-16, were implemented under the same Unet structure. The proposed method using transfer learning under the ResNet-50 encoder achieved the best Dice score of 0.9689. The proposed model’s use of two public data sets from online competitions means that it requires fewer computing resources. The difference in Dice scores between our model and 3D Unet (Isensee) was less than 1%. The average difference between the estimated kidney volume and the ground truth was only 1.4%, reflecting a seven times higher accuracy than that of conventional kidney volume estimation in clinical medicine.

Since Charnes, Cooper, and Rhodes introduced data envelopment analysis (DEA) in 1978, later called the DEA-CCR model, many studies applied this technique to different fields. Based on the original CCR model, many modified DEA models were developed by researchers. Since 1999, Seiford and Zhu presented a two-stage DEA model. Later, these models were widely used in many studies. However, the relationship between the efficiency scores that are obtained from the original CCR model and the two-stage DEA model remains unknown. To fill this gap, this study proposed a theoretical relationship between the efficiency scores that are calculated from the two-stage DEA model and those that are obtained from the original CCR model. How the sets of nonsymmetrical weights affected the efficiency scores were also investigated. Theorems regarding the relationship were developed, and then the model was utilized to evaluate the two-stage efficiency scores of the insurance companies (non-life) and bank branches. The results show that using a two-stage DEA model can get more information about operational efficiency than the traditional CCR model does. The findings from this study about the two-stage DEA technique can provide significant reasons for using this model to evaluate performance efficiency.

Three novel anthracene-based organic dyes, denoted as AN-11, AN-12 and AN-14, were synthesized for outdoor and indoor dye-sensitized solar cell studies. Laboratory-fabricated small cells, as well as rigid and flexible modules, were prepared and analyzed for their photovoltaic performance under simulated outdoor and indoor conditions. Owing to the panchromatic absorption of visible light, the AN-11 module gives rise to a very black color and superior photovoltaic performance. Significantly, the AN-11 rigid module with a large active area of 26.80 cm2 outperforms its Z907 counterpart under indoor conditions, reaching an overall efficiency of 11.94% under 1000 lux of T5 fluorescent light. In addition, the AN-11 module exhibits good stability during weather stress tests. Finally, the AN-11 dye is cost-effective and our studies show that the photovoltaic performance of the solar cells is not affected upon lowering the synthetic cost and increasing the synthetic scale.

We design a novel solution-processable polyimide ZnPor-t-DSDA with porphyrin moiety (electron donor) and sulfone-containing phthalimide (electron acceptor) for polymer memory applications. The resulting memory device can be switched from low-conductivity (OFF) to high-conductivity (ON) by both positive and negative sweeps, exhibiting symmetry biswitching characteristic with a short retention time (30 s). On the basis of the simulation calculation, the coplanar structure between donor and acceptor units results in charge transferring easily back to its original state after being excited by an electric field.

Wi-Fi wireless communication has become a basic service in public areas. However, the quality of service (QoS) might be inadequate in some areas because of the following influential factors: 1) the limited number of non-overlapping channels, 2) the interference caused by unplanned deployment and mobility, 3) the rapidly changing distribution of customers, and 4) access point (AP) failures. These factors result in non-uniform network traffic distribution and unavailability of service in some areas. Hence, this study focused on addressing the problems of AP failure and interference. We propose a self-healing algorithm to provide seamless and reliable service despite AP failures. The proposed water ripple algorithm maximizes the minimum delay difference, which is defined as the difference between transmission delay and tolerable delay, to satisfy requirements of multiple users simultaneously. Variable transmission power ranges (which involve cell breathing method types) and association management are adjusted to minimize the number of out-of-service mobile devices (MDs). Thus, fair allocation of resources to users and adequate QoS are satisfied.

A copolymerization strategy is developed to utilize porphyrin as a complementary light-harvesting unit (LHU) in D-A polymers. For polymer solar cells (PSCs), the presence of LHUs increases the short-circuit current density (Jsc ) without sacrificing the open-circuit voltage (Voc ) and fill factor (FF). Up to 8.0% power conversion efficiency (PCE) is delivered by PPor-2:PC71 BM single-junction PSCs. A PCE of 8.6% is achieved when a C-PCBSD cathodic interlayer is introduced.

Nowadays, in a dramatically changing marketplace, the integration of all of the resources in a supply chain has been regarded as an important issue for firms. However, in this complex network relationship, which links among firms, lots of uncertain factors could affect the performance of a supply chain. Thus, a structural fit model is needed to address the relationship between supply chain integration (SCI) and environmental uncertainty (EU). Empirical data for hypothesis testing are collected from top-ranked companies in Taiwan. The results show that fit specifically has a positive direct effect on supply chain performance.

In this study, we use the single-winged seeds flying model to study the relevant parameters. Afforestation used as sowing carrier stay in the air spill design to improve sowing distance. This study is further implemented the method currently carried out by Forestry Bureau for afforestation and soil conservation. This study is funded by the relevant principles of fluid dynamics to explore: physical analysis of the five seeds. Reads as follows: (1) structure and trajectory, (2) advance ratio, (3) lift thrust vs. pitch angle, (4) loading vs. terminal velocity, (5) cut-off angle area.. Finally, this study design some carrier models for testing. Spill sowing the spacing and the drift distance experiment analysis results. With experimental data, (shown in Table 2). This research used easy materials that you can make a lot. Fluid mechanical principles could be excellent learning materials for children to explore the use of teaching aids.

Video streaming hot-plug is defined as keeping video streaming to be continuous when a host is switched from wired/wireless to wireless/wired networks, or from one wireless network to another wireless network. In this paper, video streaming hot-plug mechanisms using Stream Control Transmission Protocol (SCTP), which is a new transport layer protocol supporting multihoming, are investigated. Using SCTP, a host can establish multiple paths, e.g. one through the wired network and another one through the wireless network, to communicate with its peer. Two SCTP extensions, the SCTP ADDIP extension and (Partially Reliable) PR-SCTP are adopted to implement the corresponding system called MOVIDEO. The SCTP ADDIP extension enables the host to dynamically configure IP addresses and the primary path used for the association, whereas PR-SCTP provides a partially reliable transmission option for the host to transmit data. Performance evaluation of the MOVIDEO system is provided in this paper. In addition to MOVIDEO, three other configurations of SCTP, including the triggering patterns of changing primary path and the transmission patterns of streaming video data, are implemented for performance comparison. The experimental results demonstrate that, using the proposed SCTP-based video streaming hot-plug mechanism, the connection of the video streaming service would not be broken and the playout of the video can be kept smooth during the process of video streaming hot-plug.

Kauffman's N K model—used for studying the performance of systems consisting of a finite number of components that interact with each other in complex ways—exhibits the complexity catastrophe, in which high levels of interaction in systems with a large number of components lead to a decrease in performance. It is shown here that the complexity catastrophe is a consequence of the mathematical assumptions underlying the N K model. Analysis and simulations are used to establish the idea that relaxing any one of these assumptions results in a new model in which the complexity catastrophe is attenuated. Thus, good performance from systems having high levels of interactions is possible. ©1999 John Wiley & Sons, Inc.

BACKGROUND AND OBJECTIVE: Infectious scleral ulcer is a rare but severe late complication of pterygium surgery. Scleral grafts may be required in scleral ectasia with uveal exposure, corneal distortion, and severe anterior chamber reaction that are induced by scleral ulcer. The authors report a method for scleral grafting with preserved sclera and tissue adhesive. PATIENTS AND METHODS: Six cases of infectious scleral ulcers were repaired with this method. Preserved sclera was attached to the thinning sclera with tissue adhesive without sutures. The free or rotation conjunctival flap was placed over the graft area and sutured with 10-0 nylon. RESULTS: The six cases repaired by this method showed good results during the follow-up, except for one loss. The only complication was protrusion of the adhesive postoperatively. This protrusion can be easily removed with forceps on an outpatient basis. CONCLUSION: Tissue adhesive with preserved sclera is a useful method for repair of scleral thinning. [Ophthalmic Surg Lasers 1996;27:995-999.]

The increasing volume of unsolicited bulk e-mail (also known as spam) has generated a need for reliable antispam filters. Using a classifier based on machine learning techniques to automatically filter out spam e-mail has drawn many researchers' attention. In this paper, we review some of relevant ideas and do a set of systematic experiments on e-mail categorization, which has been conducted with four machine learning algorithms applied to different parts of e-mail. Experimental results reveal that the header of e-mail provides very useful information for all the machine learning algorithms considered to detect spam e-mail.

The coupled mode equations governing the interaction of the guided magnetic waves propagating in opposite directions along a ferrimagnetic film having a periodic array of shallow rectangular grooves on one of its surfaces are deduced using quasi‐optical techniques for the case in which the magnetization is normal to the surfaces of the film. Effects caused by the deviation of the wave frequency from the Bragg frequency and by the presence of small magnetic losses are also taken into account. For a surface corrugation extending only for a finite length along the film, the longitudinal boundary value problem is solved to obtain the reflection, the transmission, and the absorption coefficients. The coupled mode equations are found to yield correctly the power conservation relation.

The partial differential equations governing the transport of the slowly varying amplitudes of the interacting guided magnetic waves supported by a yttrium iron garnet film having a periodic array of shallow grooves on one of its surfaces are deduced using quasioptical techniques for the case in which the magnetization is normal to the midplane of the film and the wave vectors are inclined to the grating vector. For the periodic array extending only for a finite length along the film, the longitudinal boundary value problem is solved for an incident‐plane guided magnetic wave to obtain the reflection, the transmission, and the absorption coefficients. The important characteristics of the reflection coefficient are examined and the various dephasing effects on the reflection characteristics are investigated.

The wave-packet of a magnetic wave on reflection at an interface between a ferrimagnetic medium and free space is shown to undergo no lateral shift but only a time delay. The time delay introduced on reflection is included to obtain a quasi-optical description for the group delay of a magnetic wave guided by a planar slab of ferrimagnet in free space for the case of the magnetizations (a) normal to the surfaces of the slab, and, (b) parallel to the surfaces of the slab and to the direction of propagation. The group delay of the guided magnetic wave is caused partly by the group delay produced in the bulk of the ferrimagnet and partly by the group delay produced on reflections. The characteristics of these two contributions to the resultant group delay of the guided magnetic wave are examined.

The reflection and transmission coefficients for the backward magnetic waves on a YIG film with periodic surface corrugations are systematically deduced from the solution of the full magnetostatic boundary-value problem. The phenomenological boundary condition for the slowly varying amplitude in the coupled mode equations is also obtained.

Magnetostatic propagation in layered structures with magnetization in the plane and perpendicular to the direction of propagation has been studied theoretically and experimentally. Problems in device application of this geometry include low power saturation levels and limited delay times for reasonable film sizes. Both problems are minimized by use of normal magnetization giving volume modes having isotropic propagation in the film plane. This work reports theoretical and experimental studies for a normally‐magnetized ground plane‐dielectric‐YIG‐dielectric‐ground plane structure. The dispersion relation is derived for the magnetostatic limit and this geometry. This theory indicates that with at least one ground plane within a magnetostatic wavelength of the YIG, significant modification of the dispersion characteristic can be obtained. Nondispersive regions of approximately 10% bandwidths are predicted. Experimental studies with an LPE‐YIG film thickness of 10μm and a dielectric thickness of 8 to 20 times the YIG thickness show nondispersive propagation over bandwidths > 100MHz at 1.6GHz. Agreement between theory and experiment is good. Saturation characteristics are better than those of similar magnetostatic surface wave devices.

The insertion loss for the magnetic waves on a periodically corrugated YIG film magnetized normal to the film surface is deduced from the solution of the full magnetostatic boundary‐value problem taking into account the effect of the finite linewidth of the ferromagnetic resonance. It is found that the contribution to the insertion loss due to the distributed reflection and the mode conversion caused by the periodic surface corrugation is decreased as the resonance linewidth is increased.