Hybrid Option Research Articles

Institutionalising the evaluation function: A South African study of impartiality, use and cost

PurposeThis article explores the implications of outsourcing the evaluation function in South Africa, a context where there is a mismatch between evaluation supply and demand. It unpacks the tradeoffs between internal and external evaluation, and challenges some commonly held assumptions about both. ApproachBased on experiences as an internal evaluator, external evaluator, evaluation manager, and building evaluation capacity, the author explores how each role changes when evaluation is a scarce skill, and looks at implications outsourcing has for both the organization, and the evaluation. FindingsThe purpose of the evaluation must drive the decision to outsource. However, with changing models of collaboration, there may be hybrid options that allow organizations to build evaluation capacity. Practical implicationsOrganisations are faced with a trade-off between commissioning an evaluation, and building internal evaluation capacity. To better understand each approach, it is important to consider the purpose and context of the evaluation. This shifts some commonly held assumptions about internal and external evaluations. Re-examining these assumptions will help organizations make a more informed decision about an evaluation approach. Originality/valueThe field of evaluation is particularly concerned with evaluation use. Most of the literature on this has focused on the approach of individual evaluators, and insufficient attention has been paid to the institutional architecture of the evaluation. This article considers how some of the organisational structures around an evaluation contribute to evidence use, and the case study of South Africa also shifts the focus to the central but overlooked role of context in the debate.

Option Pricing under the Jump Diffusion and Multifactor Stochastic Processes

In financial markets, there exists long-observed feature of the implied volatility surface such as volatility smile and skew. Stochastic volatility models are commonly used to model this financial phenomenon more accurately compared with the conventional Black-Scholes pricing models. However, one factor stochastic volatility model is not good enough to capture the term structure phenomenon of volatility smirk. In our paper, we extend the Heston model to be a hybrid option pricing model driven by multiscale stochastic volatility and jump diffusion process. In our model the correlation effects have been taken into consideration. For the reason that the combination of multiscale volatility processes and jump diffusion process results in a high dimensional differential equation (PIDE), an efficient finite element method is proposed and the integral term arising from the jump term is absorbed to simplify the problem. The numerical results show an efficient explanation for volatility smirks when we incorporate jumps into both the stock process and the volatility process.

Trade-offs between economic and environmental performance of an autonomous hybrid energy system using micro hydro

This paper evaluates the trade-offs between economic and environmental performance of an autonomous energy system utilising an existing Micro hydro power plant while improving its future reliability. The analysis primarily focuses on developing sustainable alternative to excessive reliance on Diesel Gensets in fulfilling the increasing seasonal shortfall in electricity supply from standalone Micro hydros. First, a preliminary assessment is conducted using hypothetical future shortfall in electricity supply from a Micro hydro of 10%, 20% and 30%, compared to a baseline of 2% shortfall, which shows drastic increase in the environmental costs (combined human health and ecological) by as much as 400%, 900%, 1400% respectively from continued use of conventional Diesel Genset. In the next step, a ‘Micro hydro sustainability indicator’ is formulated as the ratio of environmental costs to net present costs of different hybrid options. This is estimated through a mixed assessment framework, which combines consumer engagement for understanding the current and the projected future diurnal and the seasonal electrical loads along with quantitative evaluation of the corresponding costs. Finally, a demonstration case study implements this framework at the Khun Pang micro hydropower project in Si Lanna National Park within Chiang Mai province, northern Thailand for two scenarios – Scenario 1 (circa 2016–17, annual shortfall of 4% i.e. 571 kW h); Scenario 2 (circa 2025, projected future annual shortfall of 12.5% i.e. 3904 kW h).For smaller unmet load of up to 4% in Scenario 1, Diesel Genset turns out to be the most preferred hybrid option, irrespective of whether the environmental costs were included alongside the net present costs or not. However, for an increased future load of 12.5% in Scenario 2, including the environmental costs makes the hybrid Micro hydro-PV-Diesel-Battery system cost-competitive to the Diesel only option. Considering a 25-year project lifespan, it becomes the most sustainable solution for retrofitting micro hydro facilities in ecologically sensitive locations in order to meet future shortfall in electricity supply, with improved renewable penetration of up to 97.5%.

Mission analysis for the Martian Moons Explorer (MMX) mission

Mars Moon eXplorer (MMX) is JAXA's next candidate flagship mission to be launched in the early 2020s. MMX will explore the Martian moons and return a sample from Phobos. This paper presents the mission analysis work, focusing on the transfer legs and comparing several architectures, such as hybrid options with chemical and electric propulsion modules. The selected baseline is a chemical-propulsion Phobos sample return, which is discussed in detail with the launch- and return-window analysis. The trajectories are optimized with the jTOP software, using planetary ephemerides for Mars and the Earth; Earth re-entry constraints are modeled with simple analytical equations. Finally, we introduce an analytical approximation of the three-burn capture strategy used in the Mars system. The approximation can be used together with a Lambert solver to quickly determine the transfer Δv costs.

The Abudance Of Makrozoobenthos On Different Break Water In Semarang And Demak Coastal Area

The coast of Semarang and Demak has suffered some damage to its coastal areas. This damage is caused by natural factors and also human activities. There are number of mitigation methods such as hard, soft and hybrid that available for mitigation erosion. In Semarang and Demak coastal area using hard and hybrid option as their mitigation erotion. Breakwater is one of the way beach structure that often used as mitigation erosion di coastal area. Breakwater will cause sediment deposits that will become the living place of various organisms such as makrozoobenthos. The aim of this research is compare the abudance of makrozoobenthos in different type breakwater in Semarang and Demak coastal area.This research held on December 2016 – January 2017 in five different location with different breakwater type. Hard structure in Mangkang (West Semarang), Morosari (Demak district) and Tambak Lorok (North Semarang) and the hybrid engineering in Morosari 2 (Demak district) and Timbulsloko (Demak district). The method used in this study is descriptive comparative. Makrozoobenthos has been found in each station and the highest indeks is in hybrid engineering location. Polychaeta is a genus that dominates at every location because muddy sand is its main habitat.

Superior Short-Term Haemodynamic Outcomes When Comparing Transcatheter Aortic Valve Implantation to Sutureless Aortic Valve Replacement Using a Perceval Valve

Surgical aortic valve replacement is first line in patients with severe aortic stenosis with low to intermediate risk, while transcatheter aortic valve implantation (TAVI) has become standard of care for patients with prohibitive surgical risk. Sutureless surgical valves are potentially a hybrid option, and are reported to have improved haemodynamics when compared to other surgical valves. There is limited data comparing sutureless surgical valves and TAVI.

Hybrid Atrial Fibrillation Ablation: Current Status and a Look Ahead.

Treatment of atrial fibrillation (AF) has evolved significantly during the last 3 decades. Successful surgical AF ablation was developed by the pioneering work of Dr James Cox in 1987 resulting in the development of the Cox-maze (CM) procedure.1 Further experience and incorporation of ablation technology allowed subsequent modifications to increase efficacy and decrease morbidity, resulting in the latest iteration—the CM IV.2 Despite the excellent results of open SA of AF, its widespread use has been limited by its morbidity, especially for stand-alone surgical procedures. Ablation lines from alternate energy sources to replace many of the surgical incisions in the cut and sew maze led to a thoracoscopic, minimally invasive, off-pump beating heart approach.1 Minimally invasive thoracoscopic surgery may improve on the results of AF catheter ablation but may not be as effective as open surgery because of limitations in creating transmural lesions in roof and floor of the left atrial posterior wall in some patients.3 In 1998, the observation by Haissaguerre et al2 that the pulmonary veins (PVs) serve as common sources of AF triggers in patients with paroxysmal AF paved the way for catheter AF ablation (CA) using radiofrequency energy. Although CA is associated with relatively low morbidity, it has been characterized by higher AF recurrence rates, especially in persistent and long-standing persistent AF.4 Because thoracoscopic SA and CA interventions may lead to incomplete isolation of the PVs and the posterior wall of left atrium, a hybrid option combining these 2 techniques was developed. The so-called hybrid strategies proposed to increase procedural success. In fact, single-center studies have demonstrated that catheter ablation may be effective in completing some of the lines created by the thoracoscopic-based SA procedure.5 Hybrid AF ablations in various centers have been variable in terms of surgical approach (thorascopic …

Growth of hybrid open access, 2009-2016.

Hybrid Open Access is an intermediate form of OA, where authors pay scholarly publishers to make articles freely accessible within journals, in which reading the content otherwise requires a subscription or pay-per-view. Major scholarly publishers have in recent years started providing the hybrid option for the vast majority of their journals. Since the uptake usually has been low per journal and scattered over thousands of journals, it has been very difficult to obtain an overview of how common hybrid articles are. This study, using the results of earlier studies as well as a variety of methods, measures the evolution of hybrid OA over time. The number of journals offering the hybrid option has increased from around 2,000 in 2009 to almost 10,000 in 2016. The number of individual articles has in the same period grown from an estimated 8,000 in 2009 to 45,000 in 2016. The growth in article numbers has clearly increased since 2014, after some major research funders in Europe started to introduce new centralized payment schemes for the article processing charges (APCs).

Techno-economic design and performance analysis of nanogrid systems for households in energy-poor villages

This paper presents the techno-economic design and analysis of a nanogrid system for five neighboring houses, using an energy-poor village in Gwagwalada-Abuja, Nigeria as a case study. It explores the possibility of different energy configurations – solar nanogrid (SNg), solar/wind nanogrid (SWNg), solar/diesel nanogrid (SDNg), solar/wind/diesel nanogrid (SWDNg) and diesel nanogrid (DNg) systems. The study uses the demand patterns obtained during a field survey to determine the aggregate load profile and the energy generation systems. It presents detailed capacities, annual energy, losses, battery state of charge (SoC), unmet demand, loss of load probability (LOLP), availability and the demand growth analyses. Results reveal that 5–14.5kW SNg can meet the users’ demand of∼12.5–36.5kWh/d achieving an availability of 99.2–99.6%. However, an availability of 100% was obtained for the hybrid options, including the DNg. These are 2.5–7kW PV and a 1.8–3.6kW wind generator; 5kW PV and 5kW diesel systems; 2.5PV, 1.8kW wind and 5kW diesel system; 2.5–5kW diesel generator systems. The results also demonstrate that the hybrid nanogrids achieves better battery profiles compared to the single-source option because of their complementary characteristics; thus, satisfying the battery constraint of SoC≥30% during the year. The initial cost of the DNg option is ∼6–22% of those of the renewable energy-based nanogrids. The study further reveals that nanogrids with diesel generators have relatively higher life cycle costs because of the fuel costs. Though renewable energy-based nanogrids have relatively higher initial capital costs, their life cycle costs are lower than those of the DNg. The research can be used for planning new electrification systems for rural communities around the globe.

The Current Risk-Benefit Outlook for Endovascular vs. Open Surgical Bifurcated Aortoiliac Arterial Reconstruction Therapy for Aortoiliac Occlusive Disease

Open surgical repair (OPEN) has been the gold standard for aortoiliac (AI) disease for over seven decades. Recently, endovascular and hybrid options (ENDO/ENDO-H) have been selected increasingly to avoid aortic operations. We describe our recent concurrent experience to highlight the risks and benefits of each and provide contemporary data to our patients.

The Impact of Mechanical and Restricted Kinematic Alignment on Knee Anatomy in Total Knee Arthroplasty

BackgroundTotal knee arthroplasty (TKA), aiming at neutral mechanical alignment (MA), inevitably modifies the patient's native knee anatomy. Another option is kinematic alignment (KA), which aims to restore the original anatomy of the knee. The aim of this study was to evaluate the variations in lower limb anatomy of a patient population scheduled for TKA, and to assess the use of a restricted KA TKA protocol and compare the resulting anatomic modifications with the standard MA technique. MethodsA total of 4884 knee computed tomography scans were analyzed from a database of patients undergoing TKA with patient-specific instrumentation. The lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), and hip-knee-ankle angle (HKA) were measured. Bone resections were compared using a standard MA and a restricted KA aiming for independent tibial and femoral cuts of maximum ±5° deviation from the coronal mechanical axis and a resulting overall coronal HKA within ±3° of neutral. ResultsThe mean preoperative MPTA was 2.9° varus, LDFA was 2.7° valgus, and overall HKA was 0.1° varus. Using our protocol, 2475 knees (51%) could have undergone KA without adjustment. To include 4062 cases (83%), mean corrections of 0.5° for MPTA and 0.3° for LDFA were needed, significantly less than with MA (3.3° for MPTA and 3.2° for LDFA; P < .001). ConclusionThe range of knee anatomy in patients scheduled for TKA is wide. MA leads to greater modifications of knee joint anatomy. To avoid reproducing extreme anatomy, the proposed restricted KA protocol provides an interesting hybrid option between MA and true KA.

Online and Hybrid Water Industry Courses for Community College Students

ABSTRACTThe Water Quality Management Technology department at Red Rocks Community College in Denver, CO received a National Science Foundation grant and converted 24 courses from a face-to-face format to online and hybrid formats. The courses were converted to meet a growing employment need within the water industry. The online and hybrid options gave incumbent industry professionals, who may have a difficult schedule, the ability to keep their certifications current. In the future, the department will continue to evaluate curriculum modalities to ensure optimum student learning and cultivate more partnerships between industry and other colleges to create multiple pathways for students.

Development of a hybrid photo-bioreactor and nanoparticle adsorbent system for the removal of CO2, and selected organic and metal co-pollutants

Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide (CO2) which contribute to climate change and atmospheric pollution. There is a need for green and sustainable solutions to remove air pollutants, as opposed to conventional techniques which can be expensive, consume additional energy and generate further waste. We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces, to remove CO2, and undesired organic air pollutants using natural particles, while generating oxygen. This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO2 with a conversion rate of approximately 4% CO2 per hour, generating a steady supply of oxygen (6mmol/hr), while nanoparticles effectively remove several undesired organic by-products. We also showed algal waste of the bioreactor can be used for mercury remediation. We estimated the potential CO2 emissions that could be captured from our new method for three industrial cases in which, coal, oil and natural gas were used. With a 30% carbon capture system, the reduction of CO2 was estimated to decrease by about 420,000, 320,000 and 240,000 metric tonnes, respectively for a typical 500MW power plant. The cost analysis we conducted showed potential to scale-up, and the entire system is recyclable and sustainable. We further discuss the implications of usage of this complete system, or as individual units, that could provide a hybrid option to existing industrial setups.

TCT-815 Clinical benefits of less-invasive, device–based Left Ventricular Reconstruction: A hybrid option for patients with ischemic cardiomyopathy

TCT-815 Clinical benefits of less-invasive, device–based Left Ventricular Reconstruction: A hybrid option for patients with ischemic cardiomyopathy

Total minimally invasive esophagectomy for esophageal cancer: approaches and outcomes.

Since the introduction of minimally invasive esophagectomy 25years ago, its use has been reported in several high volume centers. With only one published randomized control trial and five meta-analyses comparing its outcomes to open esophagectomy, available level I evidence is very limited. Available technical approaches include total minimally invasive transthoracic (Ivor Lewis or McKeown) or transhiatal esophagectomy; several hybrid options are available with one portion of the procedure completed via an open approach. A review of available level I evidence with focus on total minimally invasive esophagectomy is presented. The old debate regarding the superiority of a transthoracic versus transhiatal approach to esophagectomy may have been settled by minimally invasive esophagectomy as only few centers are reporting on the latter being utilized. The studies with the highest level of evidence available currently show that minimally invasive techniques via a transthoracic approach are associated with less overall morbidity, fewer pulmonary complications, and shorter hospital stays than open esophagectomy. There appears to be no detrimental effect on oncologic outcomes and possibly an added benefit derived by improved lymph node retrieval. Quality of life improvements may also translate into improved survival, but no conclusive evidence exists to support this claim. Robotic and hybrid techniques have also been implemented, but there currently is no evidence showing that these are superior to other minimally invasive techniques.

Start-Up Financing

Entrepreneurs raise money for start-ups by acquiring debt, selling stock, mixing the two, and crowdfunding. This chapter explains the pros and cons of those start-up financing options. Start-ups must repay debt on time, which is hard for them to do before they start making profits. Stock investors collect repayment only when the start-up is acquired or goes public, but entrepreneurs cede some control of the start-up to stockholders. Hybrid options like convertible debt provide a temporary solution to some of financing problems. Crowdfunding is a new way to fundraise through peer-to-peer networks, but it works well only for a few types of start-ups. Entrepreneurs should perform careful analysis before choosing a fundraising option because fundraising has long-term consequences for start-ups.

Preserving the Seminar Experience

ABSTRACTThis article presents a new approach to online graduate education. With hopes of recruiting a larger cohort in order to preserve a graduate program struggling with low enrollment, we began offering a limited number of seats to students who would attend class in real time but from remote locations, using a videoconferencing platform. Unlike traditional asynchronous course delivery, we believed that videoconferencing would allow distance learners, with very little intervention, to enter into the give-and-take of classroom discussion and to receive instructor and student feedback in real time. We present some preliminary reflections on our initial experiences with this mode of course delivery and review the data collected from a survey distributed to students enrolled in these courses. We argue that these findings suggest this model serves as an effective hybrid option for distance learners that may help to preserve the traditional graduate seminar for programs across a variety of disciplines.

Hybrid and 4-D FFT implementations of an open-source parallel FFT package OpenFFT

The fast Fourier transform (FFT) is a fundamental kernel in a wide variety of science and engineering fields from electronic structure calculations to medical imaging. OpenFFT is an open-source package for parallel 3-D FFTs, built on a domain decomposition method with optimal communication for minimizing the volume of communication. However, OpenFFT version 1.1 does not support hybrid calculations for fully utilizing common multi-core machines and parallel 4-D FFTs. In addition, there exist several state-of-the-art open-source packages for parallel FFTs, and performance comparison among them would be interesting and helpful for potential users. In this paper, we (1) extend the functionality of OpenFFT by developing a hybrid MPI/OpenMP version and a parallel 4-D FFT, and (2) conduct performance comparison among the currently available parallel FFT packages. In the former, we first analyze the computational parts of OpenFFT to explore the opportunities for taking advantage of fine-grained parallelization with OpenMP. Based on the analysis, we implement and make comparison to choose between the two most promising hybrid options. We then develop the parallel 4-D FFT by extending the hybrid implementation of the parallel 3-D FFT. The decomposition method for 4-D FFTs preserves its 3-D original features to maximize the localization of data when transposing. In the latter, we evaluate and compare the performance of FFTE, P3DFFT, PFFT, 2DECOMP&FFT, and OpenFFT for both 3-D and 4-D FFTs on a number of different machines with varied computational scales. The evaluation results assert the benefit of the hybrid feature in improving the scalability of OpenFFT, and confirm its minimal volume of communication for 4-D FFTs in practice. Also, although no significant difference is observed in overall performance in general, there are specific cases when some packages have the edge over the others.

Thermodynamic Evaluation of Repowering Options for a Small-size Combined Cycle with Concentrating Solar Power Technology

The increasing penetration of low-carbon technologies and enhancements in fossil-fuelled power plants efficiency are some of the most important and up to date research topics.Renewable energy, in particular solar, has the potential of meeting the world energy needs while addressing environmental concerns, but technological advances in renewable energy electricity production are necessary to become competitive with conventional technologies.New opportunities to increase the penetration of renewables energies, smoothing out renewables variability and intermittency problems, come out from the hybridization concept. Hybrid renewable-fossil fuel systems join the advantages of both renewable energies and programmable devices. Among all the renewable technologies available for hybridization, Concentrating Solar Power (CSP) with parabolic trough is the most diffused because of its relatively conventional technology and ease of scale-up. CSP hybrids are well established worldwide, predominantly with natural gas: the hybridization options for CSP ranging from feed water heating, reheat steam, live steam to steam superheating.Based on a detailed thermodynamic cycle model of a reference small-size one pressure level Combined Cycle (CC) plant, the impact of CSP addition is thoroughly evaluated. Different hybrid schemes are evaluated and compared considering CC off-design operation. The goal of this study is to evaluate, from a thermodynamic point of view, three repowering options of a small-size CC with a CSP system in a hybrid system configuration and to quantify their potential benefits in terms of system's performance increase. In particular, the optimal size of CSP plant is shown for each investigated hybrid repowering options. The changes in CC steam cycle operating parameters are presented together with CC performance increase. It is shown that solar hybridization into an existing CC plant may give rise to a substantial benefit from a thermodynamic point of view.

ЗБЕРЕЖЕНІСТЬ ТОМАТІВ І ПЕРЦЮ ЗА ОБРОБКИ ЕКСТРАКТАМИ КОРЕНЯ ХРОНУ

The influence of tomato and pepper storage under exogenous extracts of horseradish root. Effect of aqueous extracts of horseradish roots leads to inhibition of the growth of bacteria and fungi, as well as inhibition sporification in fungi, that indicating the bactericidal, fungicidal and bacteriostatic effect of the extract. In addition, the aqueous extracts of the root of horseradish contain biologically active substances that show antioxidant activity. The identified polynomial feature of the reduction of the biologically active substance concentration. An average weight loss per day during use of horseradish root extract is reduced in 1.15 ... 1.36 times for tomatoes and in 1.12 ... 1.13 times for peppers. Тwo-factor dependency analysis of the average daily weight loss of the hybrid pepper and options for handling shows that under significant influence of varietal specificity, the biggest influence on the weight loss is the use of horseradish extracts. To enhance the standard products optimal horseradish extract in the ratio of raw and extractant is 1:2. The use of this extract allows to extend the storage term of tomatoes for 15 days, pepper - 4 days without reducing of standard products.