Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and...Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and Guandu square) in Kun-ming City, China, which were applied to calculate quantities of plant leaf area of these 13 species. The quantities of plant leaf area for the other 17 ornamental plant species on these squares were directly measured, and the total quantity of plant leaf area of each studied square was obtained individually. The results showed that the quantity of plant leaf area on Shengli square with ornamental plants structure composed of arbor tree species, shrub tree species and turf grass was highest among the three squares. It is believed that the design model of multi-storied vertical structure and proper tending of plant community could not only increase the quantity of plant leaf area, but also play an important role in generating ecological and landscaping benefits. Some corresponding suggestions were put forward on the basis of comprehensive analyses on the plant leaf area quantity of the three representative squares in Kunming urban area.展开更多
This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected f...This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected for use in field trials. Behaviors of bacteria activated in the reservoir, oil recovery and water cut, and the viscosity of crude oil produced through huff & puff testing and flooding with molasses-injection tests, have been investigated in situ. CJF-002, which produces biopolysaccharide, is the best among the microbes used for field trials, as it can use molasses as nutrient and produce a small quantity of CO2 and a mass of water-insoluble biopolymer. The metabolic behavior in the reservoir showed that CJF-002 had a good potentiality for MEOR.展开更多
The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, fo...The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, forest pests, and money management was briefed. Achievements made in the implementation of natural forest protection project in Haikou Forest Farm were analyzed, and problems existing in the project as well as corresponding countermeasures were expounded.展开更多
Carbon budget changes were measured on a farm near Robinson, Texas, where land originally tilled for hay production was abandoned over time periods of 10, 20, and 35 years followed by succession of prairie and forest ...Carbon budget changes were measured on a farm near Robinson, Texas, where land originally tilled for hay production was abandoned over time periods of 10, 20, and 35 years followed by succession of prairie and forest vegetation. Woody biomass accumulation increased following abandonment from 0.14 kg C m2 yr~ during forest initiation to 0.57 kg C m2 yr-1 of the mature forest Soil carbon was highest in the tilled field ( 15.77 kg C m2) with lowest in the grassland ( 11.66 kg C m-2). Soil nitrogen was highest in the tilled field (0.55 kg N ms) and lowest in the forest transition (0.38 kg N m2). Soil C:N ratios were highest in the forest transition (C:N=36) and lowest in the grassland (C:N=22). Soil respiration was constant across the site with an annual average value of 1.46 kg CO2-C m-2 yr-. Results show that land in this region may be a source of carbon for several decades following abandonment due to enhanced soil carbon emissions as a function of nutrient input shifts.展开更多
Since 194os, Mount Uludag (Bithynian Olympus) has been considered famous with winter sports center in Turkey. In addition, it is one of the rare places because of its plant diversity and is also one of the important...Since 194os, Mount Uludag (Bithynian Olympus) has been considered famous with winter sports center in Turkey. In addition, it is one of the rare places because of its plant diversity and is also one of the important plant areas of Turkey. The ski run constructions are rapidly increased in the past decades in the alpine and subalpine belts of the mountain. Rate of nitrogen mineralization and some properties of soft were investigated in the soils of the three ski runs and undisturbed neighborhood forest sites. These ski runs are at the upper part of the forest belt in the mountain. Abies bornmuelleriana forest community is the postclimax and very sensitive to destruetion. The rates of the nitrogen mineralization in the soils were determined in controlled conditions (60% water-holding capacity, 20℃). Nitrification and nitrogen mineralization were in the ski run inside where the natural recovery started, increased compared with the outside of the ski runs. Waterholding capacity, organic carbon, and total nitrogen were decreased in the massive damaged ski run, and due to these changes, the rates of mineralization and nitrification were also decreased.展开更多
This article addresses the concern of export performance among Moroccan SMEs through the paradigmatic lens of the resource based view (RBV) and international relationship marketing. Limited research exists on relati...This article addresses the concern of export performance among Moroccan SMEs through the paradigmatic lens of the resource based view (RBV) and international relationship marketing. Limited research exists on relational determinants of export performance, especially in developing countries. Furthermore, literature has been dominated during the last decade by the economic perspective. Yet, an increased attention has turned to the RBV as well as the relational perspective. Highlighting this gap, the study aims two objectives: First, to understand the scope and the nature of relational determinants, deemed as key resources, of export performance. Second, to examine which other internal and market factors are intervening as significant antecedents of the relational factors Drawing from a literature review outcomes and an in-depth interview endeavor conducted among 20 exporting firms' managers, a conceptual framework has been proposed. It's argued that exporting finns would reach great export performance by fostering successful cross-border inter-firm relationships. More specifically, the study highlight three main relational constructs, namely contractual governance, relational governance, and relationship performance. Linguistic abilities, attitude toward risk and export experience are suggested as managerial antecedents. While competitive intensity and market uncertainty are supposed to intervene as external antecedents Several hypotheses are suggested. The unit of analysis is a selected export venture. A further inquiry of the overall study is to offer hypotheses test throughout quantitative survey展开更多
Rural energy consumption in China has increased dramatically in the last decades, and has become a significant contributor of carbon emissions. Yet there is limited data on energy consumption patterns and their evolut...Rural energy consumption in China has increased dramatically in the last decades, and has become a significant contributor of carbon emissions. Yet there is limited data on energy consumption patterns and their evolution in forest rural areas of China. In order to bridge this gap, we report the findings of field surveys in forest villages in Weichang County as a case study of rural energy consumption in northern China. We found that the residential energy consumption per household is 3313 kgce yr^-1 (kilogram standard coal equivalent per year), with energy content of 9.7×lO7 kJ yr^-1, including 1783 kgce yr^-1 from coal, 1386 kgce yr^-1 from fuel wood, 96 kgce yr^-1 from electricity, and 49 kgce yr^-1 from LPG. Per capita consumption is 909 kgce yr^-1 and its energy content is 2.7×lO7 kJ yr^-1. Due to a total energy utilization efficiency of 24.6%, all the consumed energy can only supply about 2.4×107 kJ yr^-1 of efficient energy content. Secondly, household energy consumption is partitioned into 2614 kgce yr^-1 for heating, 616 kgce yr^-1 for cooking, and 117 kgce yr^-1 for home appliances. Thirdly, the associated carbon emissions oer household are 2556 kzC yr^-1, includinz1022 kgC yr^-1 from unutilized fuel wood (90% of the total fuel wood). The rest of emissions come from the use of electricity (212 kgC yr^-1, coal (13Ol kgC yr^-1 and LPG (21 kgC yr^-1. Fourthly, local climate, family size and household income have strong influences on rural residential energy consumption. Changes in storage and utilization practices of fuel can lead to the lO%-30% increase in the efficiency of fuel wood use, leading to reduced energy consumption by 924 kgce yr^-1 per household (27.9% reduction) and 9Ol kgC yr^-1 of carbon emissions (35-3% reduction).展开更多
The objective of the study was to assess factors affecting market participation of agro-forestry smallholder farmers in Uganda. Primary data on household, farm and marketing characteristics were collected from 153 far...The objective of the study was to assess factors affecting market participation of agro-forestry smallholder farmers in Uganda. Primary data on household, farm and marketing characteristics were collected from 153 farming households using a semi-structured, pre-tested questionnaire. The determinants of market participation were assessed using the Probit model. Descriptive statistics showed that a combination of crop, livestock and tree products were marketed by farmers. The main products included maize, cassava and coffee (crops); firewood and poles (tree products); and birds and goats (livestock products). Results from the Probit model showed that farm size, household size, education level, access to credit and extension visits had positive and statistically significant effects on market participation of farmers in agro-forestry products' markets. Age of farmer had a negative and statistically significant effect on the participation. Emphasis on improving the quality and coverage of extension services, extending credit facilities to farmers and intensifying agro-forestry training among farmers are suggested as avenues to enhance participation of farmers in agro-forestry products' markets.展开更多
The total annual increment in forests in Bulgaria is about 14.5 Mio m^3 of the growing stock, of which the harvesting amounts at 5-6 Mio m^3 of fallen wood. An increase of the actually harvested quantities of wood is ...The total annual increment in forests in Bulgaria is about 14.5 Mio m^3 of the growing stock, of which the harvesting amounts at 5-6 Mio m^3 of fallen wood. An increase of the actually harvested quantities of wood is possible and it may rise up to 8-10 Mio m^3. The volume of forestry waste is 1,066,900 m^3, incl. economically accessible forestry waste are 373,400 m^3. Every year, there are about 3.0 Mio m^3 of wood which are obtained by the wood category, being 2.5 Mio m^3 of that same one used by the population as fire wood for stoves about 40% efficiency. In that connection, a map has been elaborated of the economically accessible forest-wood waste from the wood harvesting. Taking into account the data on the share of that wood, is considered capable for energy production, as well as the fact that a part of fire wood shall not be used in the conventional way but shall be processed, instead, that is to say, transformed into chips, pellets and briquettes, a map of category of woods has been made for the purposes and needs of this elaboration. There are some reserves as regards to thinning operations where small- and medium-sized wood is harvested and from temporarily inaccessible forest exploitation basins or the so called "closed basins" should arrive to. This paper proposes the most promising technologies for waste processing and transformation into chips, which could be applicable in Bulgaria and in some other countries as well.展开更多
The Qianguo Ms5. 8 earthquake swarm of 2013 occurred in Qianguo, Jilin Province, China. There are five earthquakes with Ms ≥5. 0 in the Qianguo earthquake swarm, with magnitudes of Ms 5. 5, Ms 5. 0, Ms 5. 3, Ms 5. 8 ...The Qianguo Ms5. 8 earthquake swarm of 2013 occurred in Qianguo, Jilin Province, China. There are five earthquakes with Ms ≥5. 0 in the Qianguo earthquake swarm, with magnitudes of Ms 5. 5, Ms 5. 0, Ms 5. 3, Ms 5. 8 and Ms 5. 0. In this study, the far-field seismic radiated energy characteristics of the earthquakes are compared based on the source spectrum and the ground motion spectrum of the earthquake swarm. The ground motion spectrum of the five earthquakes at Changchun seismic station (CN2), which is the national standard station, is first investigated with the recorded ground motions, and then the far-field seismic radiated energy is calculated and combined with the relationships of the source spectrum to describe the variable characteristics of the Qianguo earthquake swarm. Research results indicate that the second earthquake (No. 2) with Ms5. 0 is the key event of the earthquake swarm, which occurred on October 31, the same day following the first Ms5. 5 earthquake (No.l). In fact, the magnitude of event No. 2 decreased compared to event No.l, which did not agree with its large far-field seismic radiated energy. It needs to be pointed out that event No. 2 was the turning point event of the Qianguo earthquake swarm, as being a significant transition before the largest Ms5. 8 earthquake.展开更多
Motivated by the recently discovered hidden symmetry of the type IIB Green-Schwarz superstring on certain background, the non-semisimple Kac-Moody twisted superalgebra gl(2|2)(2)k is investigated by means of the ...Motivated by the recently discovered hidden symmetry of the type IIB Green-Schwarz superstring on certain background, the non-semisimple Kac-Moody twisted superalgebra gl(2|2)(2)k is investigated by means of the vector coherent state method and boson-fermion realization. The free field realization of the twisted current superalgebra at general level k is constructed. The corresponding Conformai Field Theory (CFT) has zero central charge. According to the classification theory, this CFT is a nonunitary field theory. After projecting out a U(1) factor and an outer automorphism operator, we get the free field representation of psl(2|2)(2)k, which is the a/gebra of gl(2|2)(2)k modulo the Z4-outer automorphism, the CFT has central charge -2.展开更多
Implement agricultural "going out" strategy, guide and promote agricultural enterprises' higher and wider participation in international agricultural division of labor and cooperation, foster transnational agricult...Implement agricultural "going out" strategy, guide and promote agricultural enterprises' higher and wider participation in international agricultural division of labor and cooperation, foster transnational agricultural groups, which will help to speed up China's agricultural industrialization, internationalization and modernization, the promotion of domestic strategic adjustment of agricultural structure, the optimization and upgrading. Jilin Province shall make an integrated use of a variety of ways to strengthen the development strength of overseas market of agricultural resources and agricultural products, promote improved varieties, superior agricultural technology, equipment and agricultural products to "walk out", establish foreign grain, important industrial crop and fishery production base and independent logistics and trade system, and continuously improve the international competitiveness of China's agriculture. This thesis discusses the current research of overseas agriculture development and the major ways of the construction of Sino-Russian Cooperation Agriculture Park in Jilin Province. It also proposes the measures to accelerate the implementation of the development of Jilin Province Sino-Russian Cooperation Agriculture Park.展开更多
The Casimir energy of massive scalar field with hybrid (Diriehlet-Neumann) boundary condition is calculated. In order to regularize the model, the typical methods named as mode summation method and Green's function...The Casimir energy of massive scalar field with hybrid (Diriehlet-Neumann) boundary condition is calculated. In order to regularize the model, the typical methods named as mode summation method and Green's function method are used respectively. It is found that the regularized zero-point energy density depends on the scalar field's mass. When the field is massless, the result is consistent with previous literatures.展开更多
This article discusses the status of the ecological environment in Heihe River water source district, and points out that the decline of the forest coverage, the degradation of the pasture and the shrinking back of th...This article discusses the status of the ecological environment in Heihe River water source district, and points out that the decline of the forest coverage, the degradation of the pasture and the shrinking back of the glacier, the increased soil erosion and other phenomena are the main ecological and environmental problems in this area. The main reason is the natural and man-made results. This article proposes the specific measures to protect the ecological environment in Heihe River water source district.展开更多
In order to simplify the boundary conditions of pavement temperature field,the "Environment-Surface" system which considered the natural environment and pavement surface was established.Based on this system,...In order to simplify the boundary conditions of pavement temperature field,the "Environment-Surface" system which considered the natural environment and pavement surface was established.Based on this system,the partial differential equations of the one-dimensional heat conduction in the pavement were established on the basis of the heat transfer theory.Furthermore,the function forms of the initial and boundary conditions of the equations were created through the field experiments.The general solution of the pavement one-dimensional heat conduction partial differential equations was acquired by using Green's function,and the explicit expression of pavement temperature field under specific constraint conditions was derived.For the purpose of analysis,the pavement temperatures in different seasons were calculated using the explicit expression of pavement temperature field,and the calculation accuracy was analyzed through the comparison between measured and calculated values.Then,the relationship between fitting accuracy and calculation accuracy of pavement temperatures was analyzed.The analysis results show that: the usage of "Environment-Surface" system simplifies the calculation of pavement temperature field; the relative error between calculated and measured values is generally less than 7% and is seldom influenced by seasons; there is a positive correlation between the calculation accuracy and the fitting accuracy of pavement surface temperature; high fitting accuracy would result in less error of pavement temperature prediction.展开更多
A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Duck...A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Ducks were integrated based on the water spread area. Fodder, fruit, nuts, fuel, timber trees and vegetables were grown on pond bunds. Control units of fish ponds of farmers holding without integration of ducks also were taken up. A control unit also was established in the university farm land with and without integration of ducks. In private water bodies coconut trees and banana fetched additional revenue. During the first year the average fish production from the private land model was 1,552 kg and 1,731 kg for the first and second year respectively per Hectare. In community ponds the yields were 1,610 and 1,337 kg for the first and second year respectively. In field control units there was no increase in fish yield over the years. In private water bodies the beneficiaries got egg yield of 148 and 90 eggs and community water bodies 144 and 127 eggs per bird were obtained during first and second year resoectivelv.展开更多
The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecot...The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecotone. The ecotone position and structure are dynamic over time and space and it is driven by the changes in climate, land use or their interaction. In this context, we assessed the forest- grassland ecotone of temperate mountains in central Nepal by i) comparing species composition and richness across the ecotone, ii) analyzing if the forestgrassland ecotone is shifting towards the grassland center by colonizing them with trees, and iii) discussing the consequence of changed disturbance regime in the dynamics of this ecotone and the surrounding grasslands. We analyzed vegetation data sampled from belt transects laid across the forest- grassland ecotone in semi-natural grassland patches. Vegetation data consisting of species richness and composition, and size structure and regeneration of the two most dominant tree species, namely Rhododendron arboreum and Abies spectabilis, from the transects, were used to analyze the trend of the forest-grassland ecotone. Forest and grasslands were different in terms of floristic composition and diversity. Vascular plant speciesrichness linearly increased while moving from forest interior to grassland center. Spatial pattern of tree size structure and regeneration infers that forest boundary is advancing towards the grasslands at the expense of the grassland area, and tree establishment in the grasslands is part of a suceessional process. Temporally, tree establishment in grasslands started following the gradual decline in disturbance. We argue that local processes in terms of changed land use may best explain the phenomenon of ecotone shift and consequent forest expansion in these grasslands. We underpin the need for further research on the mechanism, rate and spatial extent of ecotone shift by using advaneed tools to understand the process indepth.展开更多
Community forestry (CF) was introduced in Cameroon in 1994 as a way to reduce poverty and enhance sustainable forest management. CF activities have primarily focused on timber exploitation rather than non-timber for...Community forestry (CF) was introduced in Cameroon in 1994 as a way to reduce poverty and enhance sustainable forest management. CF activities have primarily focused on timber exploitation rather than non-timber forest product (NTFP) collection, processing or marketing. The study reports on a two year participatory action research project that aimed to test ways of increasing access to income from NTFPs for women and people of the Baka ethnic group in nine CFs around Lomie, East Cameroon. After a participatory diagnosis of problems and stakeholders harvesting NTFPs, approaches to enhance processing, packaging, marketing, monitoring and data collection were evaluated. This led to the development of a market information system that aimed to balance supply and demandby providing information lines on market prices between buyers and sellers. Training support was provided for sustainable harvesting, and to aid harvesters to negotiate prices. This led to 100% price increase in group sales; an increase in selling prices by 39% and an increased sales volume of six NTFPs: Irvingia gabonensis, Ricinodendron heudelotii, Pentacletra macrophylla, Baillonela toxisperma, Tetrapleura tetraptera, Pleurotus tuber-regiumresulting in a sales revenue increaseof 210% (to ε772,500) between 2010 and 2012. In a context where logging is restricted to men, supporting access to NTFP markets has led to increased income for women and Baka. These results suggest that support to sustainably harvest and market NTFPs can aid development and access to markets for women and minority ethnic groups. The implications for the revision of the law on small scale commercialization, and the ability of the CFs to continue this system without support from development NGOs are discussed.展开更多
The external electric field is a special strategy for generating novel structures.In this work,the intermolecular bonding and nonlinear optical properties are affected by applying an applied electric field of 0 to 9.7...The external electric field is a special strategy for generating novel structures.In this work,the intermolecular bonding and nonlinear optical properties are affected by applying an applied electric field of 0 to 9.77 V·nm^(-1)along the bonding direction of dimer of olympicenyl radical(OLY2).The results showed that the distance between molecular layers was lengthened gradually,and the 2e/20c bonds were weakened or even completely broken(the critical electric field is 9.77 V·nm^(-1))with the increase of the external electric field strength.Moreover,the introduction of an external electric field caused significant changes in the electronic properties of the OLY2,which induced charge transfer between inter-layer monomers,and enhanced the interlayer electrostatic interactions.Therefore,the external electric field not only regulates the interlayer interactions of molecules,but also causes the symmetric molecules to produce strong polarity,producing a large NLO response in OLY2.展开更多
基金This research was sponsored by Educational Department of Yunnan Province (No. 03Z583B).
文摘Regressive formulae to calculate the quantity of plant leaf area for 13 species of ornamental plants were set up based on investigation data of 30 species on 3 major public squares (Dongfeng square, Shengli square and Guandu square) in Kun-ming City, China, which were applied to calculate quantities of plant leaf area of these 13 species. The quantities of plant leaf area for the other 17 ornamental plant species on these squares were directly measured, and the total quantity of plant leaf area of each studied square was obtained individually. The results showed that the quantity of plant leaf area on Shengli square with ornamental plants structure composed of arbor tree species, shrub tree species and turf grass was highest among the three squares. It is believed that the design model of multi-storied vertical structure and proper tending of plant community could not only increase the quantity of plant leaf area, but also play an important role in generating ecological and landscaping benefits. Some corresponding suggestions were put forward on the basis of comprehensive analyses on the plant leaf area quantity of the three representative squares in Kunming urban area.
文摘This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected for use in field trials. Behaviors of bacteria activated in the reservoir, oil recovery and water cut, and the viscosity of crude oil produced through huff & puff testing and flooding with molasses-injection tests, have been investigated in situ. CJF-002, which produces biopolysaccharide, is the best among the microbes used for field trials, as it can use molasses as nutrient and produce a small quantity of CO2 and a mass of water-insoluble biopolymer. The metabolic behavior in the reservoir showed that CJF-002 had a good potentiality for MEOR.
基金Sponsored by Science and Technology Projects of Kunming(2015-1-S-00643)
文摘The current situation about the natural forest resources protection project in Haikou Forest Farm of Kunming on the protection of forest resources, forest fire prevention, forest administration resource management, forest pests, and money management was briefed. Achievements made in the implementation of natural forest protection project in Haikou Forest Farm were analyzed, and problems existing in the project as well as corresponding countermeasures were expounded.
文摘Carbon budget changes were measured on a farm near Robinson, Texas, where land originally tilled for hay production was abandoned over time periods of 10, 20, and 35 years followed by succession of prairie and forest vegetation. Woody biomass accumulation increased following abandonment from 0.14 kg C m2 yr~ during forest initiation to 0.57 kg C m2 yr-1 of the mature forest Soil carbon was highest in the tilled field ( 15.77 kg C m2) with lowest in the grassland ( 11.66 kg C m-2). Soil nitrogen was highest in the tilled field (0.55 kg N ms) and lowest in the forest transition (0.38 kg N m2). Soil C:N ratios were highest in the forest transition (C:N=36) and lowest in the grassland (C:N=22). Soil respiration was constant across the site with an annual average value of 1.46 kg CO2-C m-2 yr-. Results show that land in this region may be a source of carbon for several decades following abandonment due to enhanced soil carbon emissions as a function of nutrient input shifts.
基金supported by the United Nations Development,Global Environment Facility,Small Grants Programme
文摘Since 194os, Mount Uludag (Bithynian Olympus) has been considered famous with winter sports center in Turkey. In addition, it is one of the rare places because of its plant diversity and is also one of the important plant areas of Turkey. The ski run constructions are rapidly increased in the past decades in the alpine and subalpine belts of the mountain. Rate of nitrogen mineralization and some properties of soft were investigated in the soils of the three ski runs and undisturbed neighborhood forest sites. These ski runs are at the upper part of the forest belt in the mountain. Abies bornmuelleriana forest community is the postclimax and very sensitive to destruetion. The rates of the nitrogen mineralization in the soils were determined in controlled conditions (60% water-holding capacity, 20℃). Nitrification and nitrogen mineralization were in the ski run inside where the natural recovery started, increased compared with the outside of the ski runs. Waterholding capacity, organic carbon, and total nitrogen were decreased in the massive damaged ski run, and due to these changes, the rates of mineralization and nitrification were also decreased.
文摘This article addresses the concern of export performance among Moroccan SMEs through the paradigmatic lens of the resource based view (RBV) and international relationship marketing. Limited research exists on relational determinants of export performance, especially in developing countries. Furthermore, literature has been dominated during the last decade by the economic perspective. Yet, an increased attention has turned to the RBV as well as the relational perspective. Highlighting this gap, the study aims two objectives: First, to understand the scope and the nature of relational determinants, deemed as key resources, of export performance. Second, to examine which other internal and market factors are intervening as significant antecedents of the relational factors Drawing from a literature review outcomes and an in-depth interview endeavor conducted among 20 exporting firms' managers, a conceptual framework has been proposed. It's argued that exporting finns would reach great export performance by fostering successful cross-border inter-firm relationships. More specifically, the study highlight three main relational constructs, namely contractual governance, relational governance, and relationship performance. Linguistic abilities, attitude toward risk and export experience are suggested as managerial antecedents. While competitive intensity and market uncertainty are supposed to intervene as external antecedents Several hypotheses are suggested. The unit of analysis is a selected export venture. A further inquiry of the overall study is to offer hypotheses test throughout quantitative survey
文摘Rural energy consumption in China has increased dramatically in the last decades, and has become a significant contributor of carbon emissions. Yet there is limited data on energy consumption patterns and their evolution in forest rural areas of China. In order to bridge this gap, we report the findings of field surveys in forest villages in Weichang County as a case study of rural energy consumption in northern China. We found that the residential energy consumption per household is 3313 kgce yr^-1 (kilogram standard coal equivalent per year), with energy content of 9.7×lO7 kJ yr^-1, including 1783 kgce yr^-1 from coal, 1386 kgce yr^-1 from fuel wood, 96 kgce yr^-1 from electricity, and 49 kgce yr^-1 from LPG. Per capita consumption is 909 kgce yr^-1 and its energy content is 2.7×lO7 kJ yr^-1. Due to a total energy utilization efficiency of 24.6%, all the consumed energy can only supply about 2.4×107 kJ yr^-1 of efficient energy content. Secondly, household energy consumption is partitioned into 2614 kgce yr^-1 for heating, 616 kgce yr^-1 for cooking, and 117 kgce yr^-1 for home appliances. Thirdly, the associated carbon emissions oer household are 2556 kzC yr^-1, includinz1022 kgC yr^-1 from unutilized fuel wood (90% of the total fuel wood). The rest of emissions come from the use of electricity (212 kgC yr^-1, coal (13Ol kgC yr^-1 and LPG (21 kgC yr^-1. Fourthly, local climate, family size and household income have strong influences on rural residential energy consumption. Changes in storage and utilization practices of fuel can lead to the lO%-30% increase in the efficiency of fuel wood use, leading to reduced energy consumption by 924 kgce yr^-1 per household (27.9% reduction) and 9Ol kgC yr^-1 of carbon emissions (35-3% reduction).
文摘The objective of the study was to assess factors affecting market participation of agro-forestry smallholder farmers in Uganda. Primary data on household, farm and marketing characteristics were collected from 153 farming households using a semi-structured, pre-tested questionnaire. The determinants of market participation were assessed using the Probit model. Descriptive statistics showed that a combination of crop, livestock and tree products were marketed by farmers. The main products included maize, cassava and coffee (crops); firewood and poles (tree products); and birds and goats (livestock products). Results from the Probit model showed that farm size, household size, education level, access to credit and extension visits had positive and statistically significant effects on market participation of farmers in agro-forestry products' markets. Age of farmer had a negative and statistically significant effect on the participation. Emphasis on improving the quality and coverage of extension services, extending credit facilities to farmers and intensifying agro-forestry training among farmers are suggested as avenues to enhance participation of farmers in agro-forestry products' markets.
文摘The total annual increment in forests in Bulgaria is about 14.5 Mio m^3 of the growing stock, of which the harvesting amounts at 5-6 Mio m^3 of fallen wood. An increase of the actually harvested quantities of wood is possible and it may rise up to 8-10 Mio m^3. The volume of forestry waste is 1,066,900 m^3, incl. economically accessible forestry waste are 373,400 m^3. Every year, there are about 3.0 Mio m^3 of wood which are obtained by the wood category, being 2.5 Mio m^3 of that same one used by the population as fire wood for stoves about 40% efficiency. In that connection, a map has been elaborated of the economically accessible forest-wood waste from the wood harvesting. Taking into account the data on the share of that wood, is considered capable for energy production, as well as the fact that a part of fire wood shall not be used in the conventional way but shall be processed, instead, that is to say, transformed into chips, pellets and briquettes, a map of category of woods has been made for the purposes and needs of this elaboration. There are some reserves as regards to thinning operations where small- and medium-sized wood is harvested and from temporarily inaccessible forest exploitation basins or the so called "closed basins" should arrive to. This paper proposes the most promising technologies for waste processing and transformation into chips, which could be applicable in Bulgaria and in some other countries as well.
基金funded by the National Natural Science Foundation,China(Grant No.41404045,No.41504047)
文摘The Qianguo Ms5. 8 earthquake swarm of 2013 occurred in Qianguo, Jilin Province, China. There are five earthquakes with Ms ≥5. 0 in the Qianguo earthquake swarm, with magnitudes of Ms 5. 5, Ms 5. 0, Ms 5. 3, Ms 5. 8 and Ms 5. 0. In this study, the far-field seismic radiated energy characteristics of the earthquakes are compared based on the source spectrum and the ground motion spectrum of the earthquake swarm. The ground motion spectrum of the five earthquakes at Changchun seismic station (CN2), which is the national standard station, is first investigated with the recorded ground motions, and then the far-field seismic radiated energy is calculated and combined with the relationships of the source spectrum to describe the variable characteristics of the Qianguo earthquake swarm. Research results indicate that the second earthquake (No. 2) with Ms5. 0 is the key event of the earthquake swarm, which occurred on October 31, the same day following the first Ms5. 5 earthquake (No.l). In fact, the magnitude of event No. 2 decreased compared to event No.l, which did not agree with its large far-field seismic radiated energy. It needs to be pointed out that event No. 2 was the turning point event of the Qianguo earthquake swarm, as being a significant transition before the largest Ms5. 8 earthquake.
基金The project supported by National Key Basic Research Program of China under Grant No. 2004CB31800, 2006CB805905 and National Natural Science Foundation of China under Grant Nos. 10231050 and 10375087 Ding thanks Prof. A. Bellen for his warm invitation and great help while Ding was staying in Trieste, where the work was partially complected. Thanks also to Prof. G. Lindi for his kindness. And the work is (partially) supported by Inistero degli Affari Esteri-Direzione Gen- erale per la Promozione la Cooperazione Culturale, and by Istituto Nazionale di Alta Matematica, francesco sev- eri (INdAM), Roma.
文摘Motivated by the recently discovered hidden symmetry of the type IIB Green-Schwarz superstring on certain background, the non-semisimple Kac-Moody twisted superalgebra gl(2|2)(2)k is investigated by means of the vector coherent state method and boson-fermion realization. The free field realization of the twisted current superalgebra at general level k is constructed. The corresponding Conformai Field Theory (CFT) has zero central charge. According to the classification theory, this CFT is a nonunitary field theory. After projecting out a U(1) factor and an outer automorphism operator, we get the free field representation of psl(2|2)(2)k, which is the a/gebra of gl(2|2)(2)k modulo the Z4-outer automorphism, the CFT has central charge -2.
文摘Implement agricultural "going out" strategy, guide and promote agricultural enterprises' higher and wider participation in international agricultural division of labor and cooperation, foster transnational agricultural groups, which will help to speed up China's agricultural industrialization, internationalization and modernization, the promotion of domestic strategic adjustment of agricultural structure, the optimization and upgrading. Jilin Province shall make an integrated use of a variety of ways to strengthen the development strength of overseas market of agricultural resources and agricultural products, promote improved varieties, superior agricultural technology, equipment and agricultural products to "walk out", establish foreign grain, important industrial crop and fishery production base and independent logistics and trade system, and continuously improve the international competitiveness of China's agriculture. This thesis discusses the current research of overseas agriculture development and the major ways of the construction of Sino-Russian Cooperation Agriculture Park in Jilin Province. It also proposes the measures to accelerate the implementation of the development of Jilin Province Sino-Russian Cooperation Agriculture Park.
基金supported by National Natural Science Foundation of China under Grant Nos.10773002 and 10875012the National Fundamental Research Program of China under Grant No.2003CB716302
文摘The Casimir energy of massive scalar field with hybrid (Diriehlet-Neumann) boundary condition is calculated. In order to regularize the model, the typical methods named as mode summation method and Green's function method are used respectively. It is found that the regularized zero-point energy density depends on the scalar field's mass. When the field is massless, the result is consistent with previous literatures.
文摘This article discusses the status of the ecological environment in Heihe River water source district, and points out that the decline of the forest coverage, the degradation of the pasture and the shrinking back of the glacier, the increased soil erosion and other phenomena are the main ecological and environmental problems in this area. The main reason is the natural and man-made results. This article proposes the specific measures to protect the ecological environment in Heihe River water source district.
基金Projects(2012zzts019,2012QNZT048)supported by the Fundamental Research Funds for the Central Universities of Central South University,ChinaProject(201306370121)supported by the State Scholarship Fund of China+3 种基金Project(JT20090898002)supported by Traffic Technology Fund of Hainan Province,ChinaProject(2012M521563)supported by the China Postdoctoral Science FoundationProject(51248006)supported by The National Natural Science Foundation of ChinaProject(511114)supported by the Natural Science Foundation of Hainan Province,China
文摘In order to simplify the boundary conditions of pavement temperature field,the "Environment-Surface" system which considered the natural environment and pavement surface was established.Based on this system,the partial differential equations of the one-dimensional heat conduction in the pavement were established on the basis of the heat transfer theory.Furthermore,the function forms of the initial and boundary conditions of the equations were created through the field experiments.The general solution of the pavement one-dimensional heat conduction partial differential equations was acquired by using Green's function,and the explicit expression of pavement temperature field under specific constraint conditions was derived.For the purpose of analysis,the pavement temperatures in different seasons were calculated using the explicit expression of pavement temperature field,and the calculation accuracy was analyzed through the comparison between measured and calculated values.Then,the relationship between fitting accuracy and calculation accuracy of pavement temperatures was analyzed.The analysis results show that: the usage of "Environment-Surface" system simplifies the calculation of pavement temperature field; the relative error between calculated and measured values is generally less than 7% and is seldom influenced by seasons; there is a positive correlation between the calculation accuracy and the fitting accuracy of pavement surface temperature; high fitting accuracy would result in less error of pavement temperature prediction.
文摘A study was taken up on integration of ducks in private and community fish ponds in Tami Nadu. A total of 50 ha of land under private holding and community water bodies each were selected to implement this model. Ducks were integrated based on the water spread area. Fodder, fruit, nuts, fuel, timber trees and vegetables were grown on pond bunds. Control units of fish ponds of farmers holding without integration of ducks also were taken up. A control unit also was established in the university farm land with and without integration of ducks. In private water bodies coconut trees and banana fetched additional revenue. During the first year the average fish production from the private land model was 1,552 kg and 1,731 kg for the first and second year respectively per Hectare. In community ponds the yields were 1,610 and 1,337 kg for the first and second year respectively. In field control units there was no increase in fish yield over the years. In private water bodies the beneficiaries got egg yield of 148 and 90 eggs and community water bodies 144 and 127 eggs per bird were obtained during first and second year resoectivelv.
基金financial support from the NOrad's Program for MAsters Studies (NOMA) at Central Department of Botany, Tribhuvan University, Kathmandu, Nepalfunded by the Norwegian Research Council (190153/V10)Grolle Olsens Legat
文摘The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecotone. The ecotone position and structure are dynamic over time and space and it is driven by the changes in climate, land use or their interaction. In this context, we assessed the forest- grassland ecotone of temperate mountains in central Nepal by i) comparing species composition and richness across the ecotone, ii) analyzing if the forestgrassland ecotone is shifting towards the grassland center by colonizing them with trees, and iii) discussing the consequence of changed disturbance regime in the dynamics of this ecotone and the surrounding grasslands. We analyzed vegetation data sampled from belt transects laid across the forest- grassland ecotone in semi-natural grassland patches. Vegetation data consisting of species richness and composition, and size structure and regeneration of the two most dominant tree species, namely Rhododendron arboreum and Abies spectabilis, from the transects, were used to analyze the trend of the forest-grassland ecotone. Forest and grasslands were different in terms of floristic composition and diversity. Vascular plant speciesrichness linearly increased while moving from forest interior to grassland center. Spatial pattern of tree size structure and regeneration infers that forest boundary is advancing towards the grasslands at the expense of the grassland area, and tree establishment in the grasslands is part of a suceessional process. Temporally, tree establishment in grasslands started following the gradual decline in disturbance. We argue that local processes in terms of changed land use may best explain the phenomenon of ecotone shift and consequent forest expansion in these grasslands. We underpin the need for further research on the mechanism, rate and spatial extent of ecotone shift by using advaneed tools to understand the process indepth.
文摘Community forestry (CF) was introduced in Cameroon in 1994 as a way to reduce poverty and enhance sustainable forest management. CF activities have primarily focused on timber exploitation rather than non-timber forest product (NTFP) collection, processing or marketing. The study reports on a two year participatory action research project that aimed to test ways of increasing access to income from NTFPs for women and people of the Baka ethnic group in nine CFs around Lomie, East Cameroon. After a participatory diagnosis of problems and stakeholders harvesting NTFPs, approaches to enhance processing, packaging, marketing, monitoring and data collection were evaluated. This led to the development of a market information system that aimed to balance supply and demandby providing information lines on market prices between buyers and sellers. Training support was provided for sustainable harvesting, and to aid harvesters to negotiate prices. This led to 100% price increase in group sales; an increase in selling prices by 39% and an increased sales volume of six NTFPs: Irvingia gabonensis, Ricinodendron heudelotii, Pentacletra macrophylla, Baillonela toxisperma, Tetrapleura tetraptera, Pleurotus tuber-regiumresulting in a sales revenue increaseof 210% (to ε772,500) between 2010 and 2012. In a context where logging is restricted to men, supporting access to NTFP markets has led to increased income for women and Baka. These results suggest that support to sustainably harvest and market NTFPs can aid development and access to markets for women and minority ethnic groups. The implications for the revision of the law on small scale commercialization, and the ability of the CFs to continue this system without support from development NGOs are discussed.
基金Foundation of Science and Technology Department of Jilin Province(20230101043JC).
文摘The external electric field is a special strategy for generating novel structures.In this work,the intermolecular bonding and nonlinear optical properties are affected by applying an applied electric field of 0 to 9.77 V·nm^(-1)along the bonding direction of dimer of olympicenyl radical(OLY2).The results showed that the distance between molecular layers was lengthened gradually,and the 2e/20c bonds were weakened or even completely broken(the critical electric field is 9.77 V·nm^(-1))with the increase of the external electric field strength.Moreover,the introduction of an external electric field caused significant changes in the electronic properties of the OLY2,which induced charge transfer between inter-layer monomers,and enhanced the interlayer electrostatic interactions.Therefore,the external electric field not only regulates the interlayer interactions of molecules,but also causes the symmetric molecules to produce strong polarity,producing a large NLO response in OLY2.