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Cell migration determines the complete development of mammalian tissue and other pathological phenomena. To investigate the effect of chemical stimuli on such behavior, cells are triggered to translate by the concentration gradient of different molecules on 2D substrates in vitro. But to date unfortunately the polymeric scaffolds for cell migration in 3D environment with chemical stimuli have not been proposed and developed yet. Herein, a novel 3D composite scaffold with an internal chemical boundary is fabricated by electrospinning and mask-assisted electrospray so that the deposition of PBG-N3 particles is confined at specific area initially. The chemical boundary is subsequently formed after selective surface modification of the particles via click reaction. Using a fluorescent alkyne, the boundary of modified regions is clearly observed by fluorescence microscope. This innovative bio-material has the potential to serve as a promising scaffold for investigating the effect of chemical stimuli on cell migration and growth in 3D environment and further on to the application in tissue engineering.

The treatment of dementia-related diseases is a global issue. Taiwan is facing a more serious dementia problem due to the combination of an aging society and a declining birthrate. A great portion of healthcare resources has been utilized for dementia among the aged population. In order to understand how dementia develops in rural areas in Taiwan, a cooperated effort between the university and a regional hospital was formed to develop a customized medical information system to collect and track dementia patients. This efficient customized system compiled information on 768 patients with dementia-released diseases. Big data technology and data mining approaches were then applied to analyze the relevant information. Using statistical analysis, we then extracted useful medical findings from the large amounts of collected medical data. Some of the findings indicate that the patients’ education level and care practices have a major effect on the dementia severity in these local senior populations.

A variety of cellulose-based polymer composite materials has been developed and show different impacts on the morphologies and properties of composites. Herein, we report the morphologies and properties of composites by blending polyurethane (PU) with either ethyl cellulose (EC) or cellulose nanofiber (CNF) through either drop-casting or electrospinning process. EC is homogenously mixed with PU without microphase separation and enhanced Young's modulus of composites from 0.04 to 6.94 MPa. The CNF is heterogeneously distributed in PU/CNF composites without interference on the PU microstructure and slightly increased modulus to 0.24 MPa. While the shearing force of the electrospinning process slightly affects the PU/EC composites, it drastically enhances PU crystallinity and Young's modulus to 54.95 MPa in PU/CNF composites. A model is established to summarize the effect of cellulose additives, compositions, and processes on PU/cellulose composites, providing a comprehensive understanding for designing future cellulose composites.

We report a sparse Ni/NiOx core-shell nanoparticle coating on an n-GaN photoanode that yields a high photocurrent by engineering junction energetics. A conventional thin film coating of high work function NiOx induces a large band bending that helps generate high photovoltage. However, the high work function causes a Fermi level downshift and compromises photopotential. The discrete core-shell nanoparticle coating balances these two effects. The Ni core creates localized large band bending to produce a high photovoltage. Meanwhile, the reduced coating surface area decreases Fermi level downshift. The resulting higher photopotential together with the catalytic NiOx shell enables a photocurrent 50% higher than NiOx thin film coating and multiple times higher than Ni nanoparticle or film coating. The localized large band bending also forms a potential well to deplete holes from semiconductor, thereby providing full surface protection against corrosion. This core-shell nanoparticle coating demonstrates a new junction energetics engineering paradigm useful for photoelectrode optimization.

Noise pollution is reported to be associated with diabetes, but few studies have elucidated the associations between noise frequency characteristics. We aimed to evaluate the relationships between different noise frequency components and incident hyperglycaemia. An industry-based cohort of 905 volunteers was enrolled and followed up to 2012. Octave-band frequencies of workstation noise and individual noise levels were measured in 2012 to classify subjects’ exposures retrospectively. We applied Cox regression models to estimate the relative risk (RR) of hyperglycaemia. An increased RR for hyperglycaemia of 1.80 (95% confidence interval [CI]: 1.04, 3.10) was found among subjects exposed to ≥ 85 A-weighted decibels (dBA) compared with those exposed to

Background: Epidemiological studies have demonstrated the association between noise exposure and diabetes, but few studies have reported the relationship between noise frequency components and fasting blood glucose. This study investigated the associations between noise levels, frequency characteristics, and the incident hyperglycemia. Methods: An industry-based cohort of 905 volunteers was enrolled and followed-up from the data of first employment to 2012. Personal noise levels and octave-band frequencies of environmental noise were measured systematically in 2012 to classify subjects’ exposure retrospectively. Cox regression models were applied to calculate the relative risk (RR) of hyperglycemia by continuous and categorical noise-exposure and frequency-component levels, adjusting for potential confounders. Results: Subjects exposed to ≥80 A-weighted decibels (dBA) had an increased RR for hyperglycemia of 1.78 (95% confidence interval [CI]: 1.11, 2.84) compared with those exposed to

Ni/NiOx core-shell nanoparticles were used to improve the water splitting efficiency and stability of an n-GaN photoanode. Nanoparticles were fabricated by thermal annealing and oxidizing a Ni thin film deposited on an n-GaN substrate. The performance of water splitting was investigated by varying Ni film thickness and oxidation time, which led to different nanoparticle distribution and NiOx thickness in the core-shell structure. Nanoparticles fabricated from a thinner Ni film led to a smaller particle-to-particle spacing. It allowed holes in n-GaN to diffuse to nanoparticle catalysts in a shorter distance for water splitting reaction, thereby providing higher photocurrent and better protection against oxidation corrosion. Ni/NiOx core-sell nanoparticles obtained from partial oxidation showed higher photocurrent than sole Ni or fully oxidized NiOx nanoparticles. It is attributed to the optimization between having more NiOx for reaction centers and keeping NiOx thin for easy hole transport from n-GaN across NiOx to NiOx/electrolyte interface for reaction.

Two types of ZnO nanostructures were electro-hydrothermally deposited on mesh 100 and 200 copper grids. To investigate the nanostructures, multiple material analyses were used to analyze the material properties. FESEM images indicate that nanoflow-ers/nanorods could be grown on the mesh 100 copper grids while a single layer of ZnO nanorods could be grown on the mesh 200 copper grids. Since the size of the grid holes might influence the chemical reactions during the growth of the nanostructures, all the other material analyzes also reveale1 distinct material characteristics of these two types of nanostructures on the copper grid. Based on the experimental results, modulating the ZnO nanostructure will be helpful for future applications of ZnO nanostructures on copper substrates.

ZnO nanoflakes were grown on the lead (Pb) plates using the electro- hydrothermal deposition methods. To investigate the influence of electrodeposition current, the ZnO seed layer was electrodeposited on the lead plates at a larger current of 160 mA (current density of 40 mA/cm2) and a smaller current of 12 mA (current density of 3mA/cm2), respectively. Then, ZnO nanoflakes were grown on top of the seed layer. Multiple analyses including field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), photoluminescence (PL) were performed on the ZnO nanostructures/Pb plates. Furthermore, surface con-tact angle measurements were conducted to study the hydrophobic properties and OD 600 antibacterial tests were used to investigate the antiseptic effects. Results indicate that the ZnO nanoflakes with the seed layer grown at a lower current of 12 mA exhibited good hydrop-hobic properties and strong antibacterial effects. ZnO nanoflakes/Pb plates show promising for future anti-radiation, antibacterial, and waterproof lead clothing applications.

Occupational noise exposure is associated with cardiovascular disease, but little is known about the contributions of noise frequency components. This retrospective study investigated the relationship between exposure to different noise frequencies and the incidence of hypertension. A cohort of 1,002 volunteers from 4 machinery and equipment manufacturing companies in Taichung, Taiwan, was followed from 1973 to 2012. Personal noise measurements and environmental octave-band analyses were performed to divide subjects into different exposure groups. Cox regression models were used to estimate the relative risk of hypertension. Participants exposed to ≥80 A-weighted decibels (dBA) over 8 years had a higher relative risk of hypertension (relative risk = 1.38, 95% confidence interval: 1.02, 1.85) compared with those exposed to

ZnO structures were electro-hydrothermally grown on copper and silver wires. To characterize the structures, multiple analyses including field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and photoluminescence measurements were performed on the ZnO structures on the wires. Results indicate that ZnO nanoflakes were densely deposited on the silver wire but poor ZnO structures were grown on the copper wire. Furthermore, OD 600 antibacterial tests revealed that ZnO flakes on the silver wire exhibited better antibacterial capability than the silver wire without ZnO nanoflakes. Because of possible integration with silver-related materials and flexibility of wire structures, ZnO nanoflake-coated silver wires have potentials for future antiseptic and biomedical applications.

Background: Few studies have reported the relationship between noise exposure and fasting blood glucose, which are risk factors of cardiovascular disease. This study investigated the association between occupational noise exposure and incident hyperglycemia. Methods: An industry-based cohort of 905 volunteers was enrolled and followed-up during 1973-2012. Personal noise levels and environmental octave-band frequency components were measured systematically in 2012 to classify subjects' exposure retrospectively. Cox regression models were used to estimate the relative risk (RR) of hyperglycemia by continuous and categorical noise-exposure and frequency-component levels, adjusting for potential confounders. Findings: Participants exposed to ≥80 A-weighted decibels (dBA) had an increased RR for hyperglycemia of 1·78 (95% confidence interval [CI]: 1·11, 2·84) compared with those exposed to

This study focuses on developing fully functional cutting stock software by utilizing an improved multi-phase heuristic algorithm to find the optimal solution for the cutting materi al. Issues which commonly appear in real-world cutting stock applications are also discussed

In this study, we address process how the ZnO nanorods were deposited on GaN substrates with spin-coating by using the hydro-thermal methods. After ZnO was spin coated, the samples were annealed with different temperatures to incorporate with Au nano particles. Multiple material analyses, such as the field emission scanning electron microscopy (FESEM), the energy dispersive X-ray spectroscopy (EDX) and the X-ray diffraction (XRD) analyses were carried out to characterize the Au nanoparticles/ZnO nanorods/GaN nanocomposites.

// Chien-Hsing Lee 1 , Sheng-Chiang Su 1 , Chi-Fu Chiang 2 , Chu-Yen Chien 2 , Chia-Chen Hsu 2 , Tzu-Yi Yu 3 , Shih-Ming Huang 3 , Yi-Shing Shieh 4 , Hong-Wei Kao 5 , Chien-Sung Tsai 6 , Yi-Jen Hung 1 and Chih-Yuan Lin 6 1 Division of Endocrinology and Metabolism, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 2 Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan 3 Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan 4 Department of Oral Diagnosis and Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 5 Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan 6 Division of Cardiovascular Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan Correspondence to: Chih-Yuan Lin, email: linrock@ms26.hinet.net Keywords: estrogen; sirtuin 1 (SIRT1); vascular smooth muscle cell; ovariectomy Received: September 13, 2017 Accepted: October 27, 2017 Published: November 10, 2017 ABSTRACT Background: There are sex differences in the incidence and severity of cardiovascular disease. Although an estrogen-mediated vasculoprotective effect is widely accepted, clinical trial results have been conflicting and the detailed mechanisms are still unclear. Sirtuin 1 (SIRT1), a class III histone deacetylase, may protect against vascular aging and atherosclerosis; however, the effects of estrogen on SIRT1 expression and vascular smooth muscle cell (VSMC) behavior remain unknown. Materials and Methods: We ovariectomized (OVX) female, wild-type, C57BL/6J mice, which were randomized into non-estrogen- and estrogen-supplemented groups. We also treated A7r5 VSMCs with 17-β-estradiol and resveratrol, a SIRT1 activator, in vitro , and measured the expression of SIRT1 and apoptotic markers, as well as proliferation, viability, and migration. Results: Aortic tissue from OVX mice exhibited marked VSMC hyperplasia and upregulation of SIRT1, which was reversed by 17-β-estradiol supplementation, as assessed by western blotting and immunohistochemical staining. In vitro , 17-β-estradiol downregulated SIRT1 expression in a dose- and time-dependent manner, increased apoptosis, and reduced proliferation, viability, and migration. Resveratrol reversed these effects through the activation of SIRT1. Estrogen appeared to mediate its effects through the Akt and ERK pathways. Conclusions: Estrogen may regulate cardiovascular health via the expression of SIRT1, possibly through the AKT and ERK signaling pathways.

This study aims to explore whether empire building firms have lower segment reporting quality under the new accounting standard-IFRS No. 8, Operating Segments. IFRS No. 8 requires firms to report segment information on basis of the management approach, which implying the opportunity of managerial manipulation. We use the sample of 8 countries that have followed IFRS 8 over the period 2009-2011, and find that when managers with high incentives to build managerial empire will conceal segment reporting information on purpose which leads to lower segment reporting quality. Furthermore, our results show that external auditors with industrial experience attenuate the agency problem of managerial empire building and consequently increase segment reporting quality.

Many diseases associated with mental deterioration among aged patients can be effectively treated using neurological treatments. Research shows that electroencephalography (EEG) can be used as an independent prognostic indicator of morbidity and mortality. Unfortunately, EEG data are typically inaccessible to modern software. It is therefore important to design a comprehensive approach to integrate EEG results into institutional medical systems. A customized EEG system utilizing a database management approach was designed to bridge the gap between the commercial EEG software and hospital data management platforms. Practical and useful medical findings are discoursed from statistical analysis of large amounts of EEG data.

The use of simulation models to manage and regulate property–liability insurers has gained in popularity over the last decade. This paper introduces a hybridized search optimization algorithm, also known as a Memetic Algorithm, for use with these insurer simulation models. The proposed algorithm combines the merits of both local and global search optimization techniques, and provides an efficient and robust approach for insurance model application. Our research investigated whether this enhanced optimization algorithm could further improve the results of a simulation model. As part of this investigation, a company-wide simulation model of a property–liability insurer was coupled with the proposed hybrid algorithm to tackle a typical multi-period asset allocation problem. The resulting asset allocations obtained by the proposed memetic algorithm coupled with the simulation model demonstrated better results than currently available investment strategies. The significant and robust improvements put forth in the present research demonstrate the great potential of our multi-phase hybrid algorithm in enhancing simulation model capabilities.

The dose-response relationship of the water-soluble carbohydrate concentrate (WSCC) from wild grape ( Vitis thunbergii Sieb.Zucc.) on intestinal health was investigated in this study. WSCC contained carbohydrates up to 71.9 g/100 g, including arabinose-rich pectic polysaccharide, hemicelluloses, glucose, and fructose. The consumption of WSCC (0.5 and 1.5 g/100 g of diet) effectively (P0.05) shortened gastrointestinal transit time (-62.3 to -63.0%), decreased toxic cecal ammonia (-59.3 to -63.0%) and daily fecal ammonia output (-29.7 to -41.4%), decreased the activities of fecal β-glucuronidase (-78.6%), β-glucosidase (-80.5 to -87.5%), mucinase (-64.6 to -72.7%), and urease (-83.2 to -86.0%), increased fecal moisture content (116-129%), and also increased short-chain fatty acid levels in cecal contents (1.8-3.3-fold). These findings suggested that consumption of wild grape WSCC might diminish the exposure of intestinal mucosa to toxic ammonia and other detrimental compounds and, hence exert, favorable effects on improving gastrointestinal milieu.

Highlights? A simulation algorithm, evolution strategies, enable slong-term investment selection of defined-contribution pensions. ? Multi-period asset allocation matches the target liability amount by ther etirement date and reduces downside risk. ? Simulations reveal promising multi-period asset investment strategies without high sensitivity to single-point forecasts. ? Algorithm results achieve higher average investment returns and lower levels of volatility under different conditions. ? With downside risk monitoring, this approach can help risk-seeking managers and investors enhance investment performance. This paper presents an optimization approach to analyze the problems of portfolio selection for long-term investments, taking into consideration the specific target replacement ratio for defined-contribution (DC) pension scheme; the purpose is to generate an effective multi-period asset allocation that reaches an amount matching the target liability at retirement date and reduce the downside risk of the investment. A multi-period asset liability simulation model was used to generate 4000 asset return predictions, and an evolutionary algorithm, evolution strategies, was incorporated into the model to generate multi-period asset allocations under four conditions, considering different weights for measuring the importance of matching the target liability and different periods of downside risk measurement. Computational results showed that the evolutionary algorithm, evolution strategies, is a very robust and effective approach to generate promising asset allocations under all the four cases. In addition, computational results showed that the promising asset allocations revealed valuable information, which is able to help fund managers or investors achieve a higher average investment return or a lower level of volatility under different conditions.

This work investigates the morphology of GaN etched in hydrogen (H 2 ) at different temperatures, the activation energies of the rate-limiting steps of H 2 etching, and the overgrowth on a H 2 -etched GaN template. The surfaces of GaN have different profiles after being etched in H 2 ; they resemble a plane decorated with columns and mooring posts in a low-temperature etching condition, and with deep cavities in a high-temperature etching condition. The etched profiles show that H 2 etching has controllable etching directions: vertical and lateral. In a low-temperature condition, H 2 etching has both vertical and lateral etching directions; however, in a high-temperature condition, it has only the vertical etching direction. The activation energies of the rate-limiting steps under etching pressures of 100 and 700 Torr are estimated to be 3.22 and 3.77 eV, respectively. A thick GaN layer has been grown on a H 2 -etched GaN template, and it has self-separated from the underlying sapphire substrate.

The Dynamic Financial Analysis (DFA) system is a useful decision-support system for the insurer, but it lacks optimization capability. This article applies a simulation optimization technique to a DFA system and use the enhanced system to search an Asset–Liability Management (ALM) solution for a Property–Casualty (P&C) insurance company. The simulation optimization technique used herein is a Genetic Algorithm (GA), and the optimization problem is a constrained, multi-period asset allocation problem that takes account of insurance liability dynamics. We find that coupling a DFA system with simulation optimization results in significant improvements over the search method currently available to the DFA system. The results were robust across random number sets. Furthermore, the resulting asset allocations changes with the asset–liability setting in a way that is consistent with the differences in the settings. Applying simulation optimization to a DFA system is therefore promising.

The U.S. Biomass Roadmap set forth a goal that, by the year 2030, biomass will supply energy approximately equivalent to 30% of current petroleum consumption. Here we report on the amount of nutrient fertilizers required to meet the proposed 1-billion tons of sustainable bioenergy biomass production annually. To meet this goal, U.S. agriculture (assuming a scenario with high yield increase and land use change) will have net removals of 40.3, 12.7, and 36.2 Tg (million tons) of N, P2O5, and K2O, respectively. The 1-billion tons of bioenergy biomass production alone will remove 16.9, 5.2, and 18.2 Tg of N, P2O5, and K2O, respectively, from U.S. agricultural land. Considering the efficiencies of fertilizers in soils and the contribution of biomass residuals in fields, the overall bioenergy-focused agriculture would require 58.2, 27.3, and 31.7 Tg of N, P2O5, and K2O fertilizers, respectively; this corresponds to an overall nutrient fertilizer application increase by a factor of 5.5 over the base line (1997). This study indicates an increased need for domestic and/or international production facilities for fertilizers if the goal of the Biomass Roadmap is to be attained.

Recent advancements in modern medical diagnoses have required a huge increase of the use of equipment such as CT and ultrasound machines. Correspondingly, the storage and dissemination of these medical images have become an important issue to medical professionals. Unfortunately, management of these images has traditionally been slow and cumbersome. With the prevalence of the personal computer, however, along with increased network bandwidth, it is now possible to handle this information electronically as well as wirelessly. The Picture Archiving and Communication System (PACS) is at the forefront of this revolution. Yet, commercially available PACS software is generally prohibitively expensive for hospitals with limited financial resources. A dilemma among many hospitals is deciding how to acquire and implement the proper PACS system without unduly affecting the budget. In this paper, a full function, efficient, and economical PACS system is presented as a viable, non-compromising option for many small and medium-sized hospitals. This system, designed and developed mainly by the physicians and technicians of Puli Christian Hospital (PCH), with the assistance from academia, allows for customization to fit the needs of individual hospitals. This system can be used as the foundation of a hospital's health information infrastructure and to enhance e-hospital service.

High fidelity simulations using mesh-based computational technologies such as computational fluid dynamics and computational structural mechanics are very important in providing valuable performance information of a design. These simulations, however, require accurate geometry representation as well as high quality meshes about the design in order to obtain accurate data. Unfortunately, while three-dimensional complex geometry is involved, it is a challenge to maintain geometry fidelity while trying to obtain high quality meshes. This paper discusses detailed information associated with non-uniform rational B-splines (NURBS) and its utilizations for geometry and mesh generation. It will go beyond regular curve and surface formulations to include NURBS volume and dynamic NURBS. Detailed NURBS formulations are described through mathematical expressions and applications to demonstrate the versatility and reliability of NURBS in geometry and mesh generation that enable high performance computational simulations.

A fuzzy multiple objective programming approach to data envelopment analysis (DEA) of imprecise data is proposed in this paper. The problems involving a mixture of imprecise and exact data for all decision making units (DMUs) could be resolved and the discriminating power of imprecise DEA (IDEA) is enhanced. Although Cooper et al. have developed IDEA to overcome the issues of imprecise data, the discriminating power is not satisfactory since too many efficient DMUs are derived. Chiang and Tzeng's approach using fuzzy multiple objective programming techniques is adopted to enhance the discriminating power of IDEA. The same data set of Cooper et al. is employed to illustrate the merit of our approach.

In this paper, the Cramér-Rao lower bound (CRLB) of image registration error using an isotropic fiducial mark is derived. The derived CRLB is a function of the intensity profile of the fiducial mark. Following the development of the CRLB, a new method for designing an isotropic fiducial mark, suitable for digital image registration, is presented. A parameterization method of the fiducial intensity profile is introduced which guarantees no aliasing effect when the fiducial mark is digitized with the proper sampling rate. A method for computing the fiducial intensity profile, based on minimization of the CRLB registration error, and subject to certain practical constraints, is developed. For imaging systems with a significant low-pass effect, it is proposed to pre-emphasize the high frequency components of the fiducial mark by converting the designed gray-scale fiducial marks into binary fiducial marks. Experimental results show that the designed fiducial mark can provide very accurate registration results and that the registration accuracy is independent of its location.

In this research, reduced graphene oxide was incorporated into the ZnO seed layer to modulate the rod diameter of ZnO nanorods (NRs) during solgel/hydrothermal growth. To characterize the reduced graphene oxide incorporated ZnO NRs, multiple material analysis techniques including field-emission scanning electron microscopy, surface contact angle measurements, X-ray diffraction, and photoluminescence were used to explore distinct properties of these size modulatable NRs. Results indicate ZnO NRs with smaller diameters could be observed with more reduced graphene oxide added into the ZnO seed layer. Furthermore, better crystallinity, higher hydrophobicity and lower defect concentration could be obtained with more amount of reduced graphene oxide added into the ZnO seed layer. The modulatable reduced graphene oxide-incorporated ZnO NRs growth is promising for future ZnO NRs based nanodevice applications.

The application of nonuniform rational B-splines to grid generation involving complex industrial geometries is discussed. Geometrical entities are transformed and represented using NURBS with common data structures. Techniques for reparameterization are discussed in terms of various grid topologies and distribution requirements. Computational examples representative of practical computational fluid dynamics applications are presented to demonstrate the success of these methodologies.

This paper addresses recent developments of grid generation techniques employing nonuniform rational B-spline formulations (NURBS). Grid refinement algorithms for arbitrary curves and surfaces with NURBS maintain high fidelity of the geometry, and allow time-efficient interactive grid generation. Bezier curve formulations are utilized to subdivide surface patches to accomplish a smooth and near orthogonal zonal grid. A CAD/Grid interface code based on NURBS formulations has been developed which converts CAD data from IGES files into the format accepted by the structured grid system. Two interactive grid generation codes, a general-purpose code and a customized one for turbomachinery configurations, have been developed on the basis of NURBS' definition.

This paper describes an intellectual organic farming system surrounding the organic authentication center based on three business value models: value chain, value shop, and value network, to create high-end agricultural businesses in the era of the Internet and environmentalism. This system further handles four types of value sources of e-business: efficiency, complementarities, lock-in, and novelty, in order to elaborate the sustainable competitive functions of an agricultural e-business. Finally, the authors illustrate a conceptual framework, including related functional deployment of e-farming value chain, value shop, and value network, to articulate the intellectual farming system with the competences of competitive advantage, knowledge management, and business scalability.

This paper presents a new method for the relaxation of multiview registration error. The multiview registration problem is represented using a graph. Each node and each edge in the graph represents a 3-D data set and a pairwise registration, respectively. Assuming that all the pairwise registration processes have converged to fine results, this paper shows that the multiview registration problem can be converted into a quadratic programming problem of Lie algebra parameters. The constraints are obtained from every cycle of the graph to eliminate the accumulation errors of global registration. A linear solution is proposed to distribute the accumulation error to proper positions in the graph, as specified by the quadratic model. Since the proposed method does not involve the original 3-D data, it has low time and space complexity. Additionally, the proposed method can be embedded into a trust-region algorithm and, thus, can correctly handle the nonlinear effects of large accumulation errors, while preserving the global convergence property to the first-order critical point. Experimental results confirm both the efficiency and the accuracy of the proposed method.

In this paper, based on the anisotropic nature of hydrogen (H2) etching on GaN, we describe a new approach to the removal of threading dislocations in GaN layers. The top surfaces of c-plane (Ga-face) and a-plane GaNs are considered stable in H2; therefore, H2 etches only crystal imperfections such as dislocation and basal plane stacking fault (BSF) sites. We used H2 to etch undoped c-plane GaN, n-type c-plane GaN, a-plane GaN, and an InGaN/GaN multiple quantum well structure. Several examinations were performed, indicating deep cavities on the c-plane GaN samples after H2 etching; furthermore, gorge-like grooves were observed on the a-plane GaN samples. The deep cavities on the c-plane GaN were considered the etched dislocation sites, and the gorge-like grooves on the a-plane GaN were considered the etched BSF sites. Photoluminescence measurements were performed and the results indicated that the H2-etched samples demonstrate superior optoelectronic properties, probably because of the elimination of dislocations.