Remote Hybrid Research Articles

Design requirements for medium-sized wind turbines for remote and hybrid power systems

This paper provides an overview of the design requirements for medium-sized wind turbines intended for use in a remote hybrid power system. The recommendations are based on first-hand experience acquired at the University of Massachusetts through the installation, operation, and upgrade of a 250-kW turbine on a mountain top with difficult access in Western Massachusetts. Experience with the operation of this turbine and the design of its control system, together with a long history in the design and analysis of hybrid power systems, has made it possible to extend the work in Western Massachusetts to remote or hybrid power systems in general. The University test site has many attributes of more remote sites and the overall wind turbine installation is typical of one that could power a hybrid wind system. For example, access to the site is limited due to steep terrain, snow, and environmental restrictions. Also, the power lines feeding the turbine exhibit voltage sags and phase imbalance, especially during start-up. This paper is based on the experience gained from the operation of this wind turbine and assesses the requirements for the design and operation of medium to large wind turbines in remote locations. The work summarizes lessons learned relative to: (1) sensors, communication, and control capabilities; (2) grid connection issues; and (3) weather-related problems. The final section of the paper focuses on design requirements to ensure successful installation and the completion of maintenance and repairs at remote sites.

Pattern of formation of nuclear chromosomal apparatus after remote hybridization in wheat and buckwheat: effect of low temperature

We studied the pattern of embryo formation in wheat and buckwheat interspecific hybrids. Formation of non-reduced gametes in the embryo sac was induced by low temperature (4-7 degrees C). Changed thermal conditions during meiosis proved to favor formation of hybrid embryos. Vital embryos have been obtained. Karyotypic analysis on the metaphase plates from the root meristem demonstrated different genotypes. Heterogeneous embryos caring both maternal and paternal chromosomes as well as the embryos caring solely maternal or paternal chromosomes have been revealed. Spermatozoa penetrate the embryo sac as a cell, which increases aminopeptidase activity. Sometimes low temperature induces formation of somatic embryos from nucellus cells in the plants.

Modes of speciation and evolution of the sections inTaraxacum

Modes of evolution of species classified within different sections inTaraxacum involve diverse processes, viz. primary divergence of an ancestral sexual diploid, hybridization between a tetraploid apomict and a diploid sexual hybrid, differentiation of an advanced apomictic taxon at one ploidy level, hybridization between a sexual tetraploid and a sexual diploid, formation of a polyploid series from an apomictic ancestor of a lower polyploidy level, and remote hybridization between an autumn-flowering ancestral diploid and a spring-flowering derivative diploid or apomict. Various reproduction systems of the plants involved, different environments and different timing of the processes contribute to a very varied nature of the species groups.

Optimal dispatch strategy in remote hybrid power systems

For small villages in developing countries, local stand-alone power systems are often more cost-effective than utility grid extension. Various combinations of wind turbine generators, photovoltaic arrays, diesel gensets, and batteries—remote hybrid power systems—may be preferred to diesel-only systems. Dispatch strategy is the aspect of control strategy that pertains to energy flows among components. In systems with both batteries and diesel genset(s), dispatch affects the life-cycle cost through both the fuel usage and the battery life. In this study, dispatch strategies are compared using (1) an analysis of cost trade-offs, (2) a simple, quasi-steady-state time-series model, and finally (3) HYBRID2, a more sophisticated stochastic time-series model. An idealized predictive dispatch strategy, based on assumed perfect knowledge of future load and wind conditions, is developed and used as a benchmark in evaluating simple, non-predictive strategies. The results illustrate the nature of the optimal strategy and indicate that one of two simple diesel dispatch strategies—either load-following or full power for a minimum run time—can, in conjunction with the frugal use of stored energy (the Frugal Discharge Strategy), be virtually as cost-effective as the Ideal Predictive Strategy. The optimal choice of these two simple charging strategies is correlated to three dimensionless parameters, yielding a generalized dispatch design chart for an important class of systems.

Some Aspects of Development and Application of Plant Biotechnology in Bulgaria

ABSTRACTBiotechnological methods which supplemented the conventional breeding methods are extremely valuable today because of the high contamination level of the environment with insecticides, herbicides and artificial fertilizers. The review describes current investigations of tissue and cell cultures in Bulgaria which began at the end of the sixty's. The main directions of our investigations are: clonal micropropagation combined with virus elimination; overcoming the incompatibility in remote hybridization; haploid production; somaclonal and gametoclonal variation; in vitro mutagenesis and cell selection; protoplasts culture, somatic hybridization and transformation in economically important plant species.

Anther culture application to breeding of a restorer for a male-sterile cytoplasm of wild rice (ms-CW).

Breeding of a restorer line for the male-sterile cytoplasm [ms-CW] of wild rice (W 1 ; Oryza rufipogon Griff.), identified by KATSUO and MIZUSHIMA (1958), was demon-strated by transferring the restoring gene(s) of W 1 to a cultivar through anther culture. Anthers of the F1 hybrid between W I (=) and O. sativa L. cv. Somewake (=) were cultured and two regenerated plants with high pollen stainability were obtained. Of these two plants, one was sterile in seed set, but the other (A1) was fertile and its selfed progenies (A2) also showed a high seed fertility. In a test cross of one of A 2 plants (=) with a cytoplasmic male-sterile strain carrying the cytoplasm of W1 and the nucleus of cv. Reimei, the resulting F1 gave a high seed fertility, demonstrating that the regenerated plant (A1) possessed restorer gene(s). The F2 and BIFI progenies of W1 (=)/Somewake in the conventional crossing showed a wide variation in pollen stainability and seed fertility, that might be due to not only cytoplasmic but also genic hybrid sterility. These results suggest that anther culture is effectively utilized for breeding restorer lines from remote hybrids, especially when they suffer from hybrid sterility.

A modem for remote hybrid computer terminals—Design and applications

The design and construction of a modem for a remote hybrid computer terminal is described. This modem utilizes both existing and newly developed equipment to provide true remote access through the switched telephone network to a hybrid computer facility. The unit is used in conjunction with an on-campus, hard wired, remote terminal system. Together, these terminals permit both on- and off-campus students to participate in a new set of simulation laboratories.

HYBRIDIZATION IN TARAXACUM

SummaryResults of hybridization experiments between twenty‐six species of Taraxacum (nine of which are sexual) are reported. Most crosses set good seed. The chief barriers to interspecific hybridization seem to be absence of sexuality, absence of pollen and restitutional pollen. There is no evidence of seed‐incompatibility. Taxonomically remote hybrids set less good seed than near interspecific hybrids.Hybrids are intermediate in character and usually more vigorous than the parents. The progeny of diploid sexual males are fertile, diploid and sexual, those of triploid agamospermous males are mostly near‐diploid, fertile and sexual, but some are facultatively agamospermous triploids.The existence of several intraspecific character differences is noted in some sexual species and the nature of character inheritance is noted in interspecific hybrids.The nature of hybrids in the field is discussed and examples of hybrid populations reported. The scarcity of reports of hybrids is noted and reasons for this are discussed.

USE OF INTERSPECIFIC CROSSES IN GOOSEBERRY BREEDING

Data on using remote hybridization (interspecific crosses) with Grossularia robusta species in gooseberry breeding are given. This species is characterized as a source of valuable characters for obtaining hybrids resistant to powdery mildew and leaf spots as well as high adaptability to unfavorable abiotic factors of the environment, i.e. heat and drought resistance and frost hardiness. We have involved this species into breeding since 2001. As a result, F1 and F2 progenies of remote hybrids have been obtained and promising selective seedlings have been allocated, which combine a complex of biological and commercially valuable characters (resistance to powdery mildew and leaf spots, high yields, large size of fruit and general high adaptability to abiotic factors of the environment). An analysis was conducted on American mildew and shot hole (anthracnose, septoriosis) sensibilities of 389 hybrid seedlings from 15 hybrid families obtained from distant (interspecific) crosses with the participation of Grossularia robusta species as a paternal parent and mother parent previously obtained hybrid forms from the VNIISPK selection fund, which were characterized by a fairly high level of damage to both American mildew (up to 3 points) and shot holes (3-4 points).

The creation of the domestic varieties of peony using the method of distant hybridization

Aim. The creation of the domestic varieties of herbaceous peonies, early flowering period, with the original shape and color of the flower that are resistant to viral, bacterial and fungal diseases. Methods. To obtain hybrids were used different types of crosses: interspecific, recurrent, polyhybrid, reciprocal. Results. As a result of hybridization was obtained a series of distant hybrids with fundamentally new donor characteristics in the structure, originality and color purity of the flower, which had not met in varieties of P. lactiflora. Especially valuable is the fact that in selected hybrids of these qualities combined with very early and early flowering. Conclusions. Discovered large the forming capabilities of the distant hybridization, which are not only in the combination of useful traits of the original forms, but also the emergence of many new, not peculiar to the parent. The nature and amplitude of variability depends on the combinations of crosses. In the State register of plant varieties suitable for distribution in Ukraine included 32 varieties of peony breeding NBG, 26 of them were created using the selection method of distant hybridization.
 Keywords: selection, variety, species, a gene pool, the remote hybridization.

MONITORING OF BLACK CURRANT VARIETIES RESISTANCE TO COLUMNAR RUST

As a result of the studies, we found that the bulk of the studied black currant varieties are more or less susceptible to columnar rust. Both derivatives of the European, Siberian subspecies and dikusha currant and species obtained with usage Scandinavian subspecies are characterized by high sensibility to this disease. In the European zone the most widespread and harmful are the fungal diseases of black currant - septoriosis, anthracnose, powdery mildew. Substantial damage to this culture plantations is caused by epiphytoty which repeated every three to four years. In contrast to American mildew, columnar rust intensely affects plants during the mass ripening of berries, which makes it difficult to carry out protective measures. The most effective method for solving this problem was the remote hybridization which is participation of wild species with the necessary characteristics, but their involvement leads to deceleration of the selection process, as apart from the necessary characteristics they have those that reduce the value of hybrid progeny, and it takes several hybrid generations to achieve the necessary results. In the Institute on the base on disjoining of hybrid progeny was established the oligogenic nature of the inheritance of resistance to columnar rust in currant derivatives. It was revealed that it confers immunity to columnar rust in addition combines immunity with American powdery mildew. As a result, the Re gene was identified, as well as Kipian and Gamma varieties, which are actively used as immunity donors. Assessment of varieties for resistance to diseases and pests was carried out in the areas of primary variety testing according to the methodology for the study of fruit, berry and nut-bearing crops.

AGROTECHNICS (HABIT) OF HYBRID FORMS OF INDUSTRIAL TYPE GOOSEBERRIES BUSHES

The condition for the revival of industrial gooseberry culture is the creation of cultivars that would have a number of economically useful features that are necessary for intensive cultivation technologies and, in particular, adapted to the conditions of mechanized harvesting. The existing assortment of gooseberries is characterized, as a rule, by the parameters of the industrial cultivar that do not correspond sufficiently to the general architectonics of the bush , i. e. compact, straight-growing (orthotropic) growth type, optimal values of the height of the bush, the width of the crown and the width of the base of the bush. Although these parameters are not limiting, they are important for the conditions of machine harvesting. Our research shows that the use of the wild-growing species Grossularia robusta in breeding makes it possible to obtain selective breeding forms in the hybrid generation that meet the requirements for industrial-type cultivars for a number of economically useful characteristics. Since 2001, the Institute has been actively engaged in breeding work with the use of the G. robusta species in breeding programs. Numerous offspring of remote hybrids of this species were obtained and selected forms were identified, characterized by a complex of economically useful traits (the habit of the bush suitable for mechanized harvesting, productivity, sufficient berry weight and resistance to diseases and pests). This article discusses some aspects of the architectonics of the bush in selected forms of second-generation gooseberries obtained from remote crosses with the G. robusta species. It is shown that the prevailing number of selected forms are characterized by optimal indicators of the height of the bush: the average height of the bush is 127 cm, the diameter of the crown of the bush is 107 cm, the width of the base of the bush is 28 cm and the seedlings meet the requirements for mechanized harvesting. When combining the indicators of the architectonics of the bush with the mass of berries, yield, disease resistance and weak thorniness, there is a real prospect of creating industrial-type gooseberry cultivars and reviving the culture on an industrial scale.

Irradiated mentor pollen: its use in remote hybridization of black cottonwood.

REMOTE hybridization, the bringing together of distantly related genomes, has many useful purposes1–4 but is often hindered by incompatibility barriers. Pollen mixes have been successfully used, particularly by the Michurin school of plant breeders, to overcome such incompatibility barriers1,2,5. Often, these mixes combined the pollen intended for syngamy with “mentor” pollen of the maternal species the function of which it was to stimulate the female floral tissue. Although the chemical nature of the stimulus is still poorly understood, it is likely that specific enzymes and hormones play an important part in the process6–8.

On the Karyotype of a Viviparous Onion, Known asAllium CepaL. Var.Viviparum(Metzg.) Alef

SUMMARYCytological analysis of a viviparous onion, known as Allium cepa L. var. viviparum (Metzeg.) Alef., showed that this onion presents a caryogram quite different from the one that characterizes Allium cepa. Moreover, in the viviparous onion, all interphase nuclei have only one nucleolus instead of two, as it is generally in Allium cepa. Data obtained from cytological analysis of viviparous onion, together with its morphological characteristics, lead to the hypothesis that this line should be considered a clone derived from a more or less remote hybridization between Allium cepa and Allium fistulosum.The lack of sexual reproduction does not justify, according to the Author's opinion, the establishment of a taxonomical entity, such as a botanical variety; this viviparous onion could be better defined as a «cultivar» as it is done in several clonally propagated fruit and horticultural species.