113 research outputs found

    Sampling-based learning control of inhomogeneous quantum ensembles

    Full text link
    Compensation for parameter dispersion is a significant challenge for control of inhomogeneous quantum ensembles. In this paper, we present a systematic methodology of sampling-based learning control (SLC) for simultaneously steering the members of inhomogeneous quantum ensembles to the same desired state. The SLC method is employed for optimal control of the state-to-state transition probability for inhomogeneous quantum ensembles of spins as well as Λ\Lambda type atomic systems. The procedure involves the steps of (i) training and (ii) testing. In the training step, a generalized system is constructed by sampling members according to the distribution of inhomogeneous parameters drawn from the ensemble. A gradient flow based learning and optimization algorithm is adopted to find the control for the generalized system. In the process of testing, a number of additional ensemble members are randomly selected to evaluate the control performance. Numerical results are presented showing the success of the SLC method.Comment: 8 pages, 9 figure

    Ethnobotanical study on wild plants used by Lhoba people in Milin County, Tibet.

    Get PDF
    The Lhoba are a small ethnic group, located in the Tibet Autonomous Region of China. Until 1960, their livelihood was predominantly based on swidden agriculture, hunting, and gathering. To investigate and document the plant species used by the Lhoba, ethnobotanical surveys were conducted in three villages of Nanyi Township in Milin County, Tibet, China. Ethnobotanical surveys were conducted in three Lhoba villages using key informant interviews and semi-structured interviews. Plants traditionally used by the Lhoba were documented. Data obtained were analyzed through informant consensus factor analysis (FIC) to determine the homogeneity of the informants’ knowledge of medicinal plants. Fifty-nine plant species belonging to 49 genera and 28 families were recorded and collected. Twenty-eight species are ethnomedicinal plants, 29 are local edible plants, and 23 are used for other purposes in Lhoba daily life. The medicinal plant species are used for treating eight categories of illness. Most medicinal plants are herbs (71.4%) or roots (39.2%). Nutrition adjustment (FIC = 0.76) and dermatological infections (FIC = 0.56) showed the highest FIC, indicating that the Lhoba had the highest level of agreement about the use of plants for these two illness categories. Fruit is the most frequently used part of the edible plants. Nine edible plant species are used as herbal medicine. Plant species used for other purposes include, six species for fuel, five for dye material, six for religious use, four for timber, two for tobacco substitutes, and one for fodder. Some traditional technologies and customs of Lhoba, such as dyeing and bamboo weaving, have remained the same for centuries. In contrast, the Lhoba’s knowledge of ethnomedicine has been recently influenced by traditional Tibetan and Chinese medicine, resulting in the loss of traditional knowledge in this sector. In addition, the development of tourism has influenced a change in the Lhoba lifestyle and their production of traditional products. These events signal the need to invest in mechanisms that can enable the Lhoba to benefit from the use of their traditional plant-derived culture and therefore support the continued conservation and use of these important plant resources

    Medicinal plants used by Tibetans in Shangri-la, Yunnan, China

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Medicinal plants used by the local people in Xizang (Tibet) have been investigated since the 1960s. The others out of Xizang, however, have been less understood, although they may be easily and strongly influenced by the various local herbal practices, diverse environments, local religious beliefs and different prevalent types of diseases. In 2006, two ethnobotanical surveys were organized in the county of Shangri-la, Yunnan Province, SW China, to document the traditional medicinal plants used by the Tibetan people.</p> <p>Methods</p> <p>After literature surveying, four local townships were selected to carry out the field investigation. Three local healers were interviewed as key informants. The methods of ethnobotany, anthropology and participatory rural appraisal (PRA) were used in the field surveys. Plant taxonomic approach was adopted for voucher specimen identification.</p> <p>Results</p> <p>Sixty-eight medicinal plant species in 64 genera of 40 families were recorded and collected. Among them, 23 species were found to have medicinal values that have not been recorded in any existing Tibetan literatures before, and 31 species were recorded to have traditional prescriptions. Moreover, the traditional preparations of each species and some folk medicinal knowledge were recorded and analyzed. These traditional prescriptions, preparations, new medicinal plants and folk medicinal knowledge and principles were discovered and summarized by local traditional Tibetan healers through times of treatment practices, and were passed down from generation to generation.</p> <p>Conclusion</p> <p>As a part of the cultural diversity of Tibetan community, these traditional medicinal knowledge and experiences may provide data and information basis for the sustainable utilization and development of Tibetan medicine, and may contribute to the local economic development. However, for many reasons, they are disappearing gradually as time goes by. Our study showed that there were abundant traditional Tibetan medicinal prescriptions and using methods. It implies that more Tibetan medicinal plants and traditional knowledge can be discovered. Further research should be done to save the wealth of these traditional medicinal knowledge and experiences before they are dying out.</p

    Ethnobotanical survey of cooling herbal drinks from southern China

    Full text link

    N

    Full text link

    Assessment of the resilience of a Tartary Buckwheat (Fagopyrum tataricum) cultivation system in Meigu, Southwest China

    Get PDF
    Recent socioeconomic development, increased transport and new agricultural technology are endangering the survival of traditional agriculture and the Yi people’s traditional knowledge of cultivating Tartary buckwheat. The cultural heritage of Tartary buckwheat cultivation among the Yi communities needs to be investigated and protected before its loss. The main objectives of this study are to document the Tartary buckwheat cultivation system, to analyze the agroecosystem networks that support the current system, and to measure the resilience of the ecological, agricultural and social systems using relevant indicators. The Tartary buckwheat cultivation system in Meigu County uses a rotation system, in which various crops are planted alternatively (e.g., Tartary buckwheat, green manure and potato/corn), utilizing bunch planting and furrow drilling technology. Tartary buckwheat has an important position in the major festival activities among the Yi people’s communities. Network analysis on the current agricultural system, ecosystem and social system indicated that the system was stable. The mean score of ecological, agricultural and social stability were 2.50, 2.85 and 2.53, respectively, indicating moderately stability. In contrast, socio-ecological production landscapes and seascapes (SEPLS) resilience indicators in Meigu performed only moderately, with a score of 2.63. The assessment of the resilience of the Tartary buckwheat cultivation system can provide some guidance for policy makers to strengthen biodiversity conservation, sustainable agricultural production and livelihood development (e.g., land use, responding to extreme environmental stresses and improving education levels)

    Assessment of the resilience in SEPLS (Socio-Ecological Production Landscapes and Seascapes) in Yanuo Village, Xishuangbanna, Southwest China

    Get PDF
    Participatory ‘assessment workshops’ were held in 2018 in Yanuo Village, Xishuangbanna, Southwest China. The ‘Indicators of Resilience in Socio-Ecological Production Landscapes and Seascapes (SEPLS)’ tool was used to provide the community with a framework for discussion and analysis of socio-ecological processes essential for resilience. Workshops were planned and implemented by local people together with researchers from outside the community. Discussion, including a scoring process, was undertaken using a subset of twenty indicators designed to capture the communities’ perceptions of factors affecting the resilience of their landscapes. The indicators were also used to provide the local community with a framework to discuss both current conditions of resilience and potential areas for improvement. A key result was that the existing community management approach did not include loss of traditional knowledge as a factor that would impact on the livelihoods and well-being of the community. A mechanism to encourage young people to inherit and actively use traditional knowledge was agreed to be necessary and included in economic activities. In addition, the socio-economic infrastructure in the community needs further improvement. This community management assessment framework in Yanuo Village can be scaled out to other communities in tropical montane regions with similar socio-economic environments by supporting stakeholders (policymakers, NGOs and development agencies, etc.)

    Ethnobotany of dye plants in Dong communities of China

    Get PDF
    BACKGROUND: Dyes derived from plants have an extensive history of use for coloring food and clothing in Dong communities and other indigenous areas in the uplands of China. In addition to use as coloring agents, Dong communities have historically utilized dye plants for their value for enhancing the nutritive, medicinal and preservative properties of foods. However, the persistence of plant-derived dyes and associated cultural practices and traditional knowledge is threatened with rapid socio-economic change in China. Research is needed to document the ethnobotany of dye plants in indigenous communities towards their conservation and potential commercialization as a sustainable means of supporting local development initiatives. METHODS: Semi-structured surveys on plants used for coloring agents and associated traditional knowledge were conducted in fifteen Dong villages of Tongdao County in Hunan Province of South Central China during 2011–2012. Transect walks were carried out with key informants identified from semi-structured surveys to collect samples and voucher specimens for each documented plant species for taxonomic identification. RESULTS: Dong households at the study sites utilize the flowers, bark, stems, tubers and roots of 13 plant species from 9 families as dyes to color their customary clothing and food. Out of the documented plants, a total of 7 are used for coloring food, 3 for coloring clothing and 3 for both food and clothing. Documented plants consist of 3 species that yield black pigments, 3 for brownish red/russet pigments, 3 for red pigments, 2 for dark blue pigments and 2 for yellow pigments. In addition to dyes, the plants have multiple uses including medicinal, ornamental, sacrificial, edible, and for timber. CONCLUSIONS: The use of dyes derived from plants persists at the study sites for their important role in expressing Dong cultural identity through customary clothing and food. Further research is needed to evaluate the safety of dye plants, their efficacy in enhancing food items and their commercial potential. Conservation policies and management plans are called for to preserve these ethnobotanical resources in a sustainable manner that supports local livelihoods while maintaining cultural practices
    • …
    corecore