Signal-Frequency Signaling System for Supervision and Dialing over Long-Distance Telephone Trunks

The zero-cross modulation technology is a communication technology for distribution network, different from the traditional distribution network power line carrier communication technology. Its basic principle is to use the TWACS of the power frequency voltage fundamental wave to realize the signal transmission, and the modulation signal frequency is low It can be long-distance communication across the transformer. The data reliability and data through rate are high. It has broad application prospects in real-time communication less demanding situations. This paper first introduces the principle of the zero-cross modulation technology, and then details the generation and the identification of the voltage modulation signal. Practice shows that the transmission success rate of zero-cross modulation signal is up to100%. Meet the actual needs.

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Theories of ethnicity and the dynamics of ethnic change in multiethnic societies

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1421406112 ◽

2015 ◽

Vol 112 (30) ◽

pp. 9176-9181 ◽

Cited By ~ 13

Author(s):

Richard E. Blanton

Keyword(s):

Ethnic Group ◽

Costly Signaling ◽

Signaling System ◽

Long Distance ◽

Collective Management ◽

Effective Form ◽

Management Of Resources ◽

Specialist Trading ◽

Group Members ◽

Multiethnic Societies

I modify Fredrik Barth’s approach, which sees ethnic group building as a signaling system, to place it within a framework that draws from collective action and costly signaling theories. From these perspectives, ethnic signaling, although representing a costly penalty to group members, is one effective form of communication that facilitates collective management of resources. I then identify three contexts in which the benefits of ethnic group building are likely to outweigh its signaling costs: in politically chaotic refuge and periphery zones; in the context of long-distance specialist trading groups; and within the territorial scope of failed states. I point to selected data from the Mughal and Aztec polities to illustrate how a combination of effective public goods management, in highly collective states, and the growth of highly integrated commercial economies will render ethnic group building superfluous.

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Systemic Optimization of Legume Nodulation: A Shoot-Derived Regulator, miR2111

Frontiers in Plant Science ◽

10.3389/fpls.2021.682486 ◽

2021 ◽

Vol 12 ◽

Author(s):

Nao Okuma ◽

Masayoshi Kawaguchi

Keyword(s):

Recent Progress ◽

Root Nodules ◽

Soil Nutrient ◽

Nutrient Deficiencies ◽

Signaling System ◽

High Concentration ◽

Long Distance ◽

Legume Nodulation ◽

Rhizobial Inoculation ◽

Nutrient Changes

Long-distance signaling between the shoot and roots of land plants plays a crucial role in ensuring their growth and development in a fluctuating environment, such as with soil nutrient deficiencies. MicroRNAs (miRNAs) are considered to contribute to such environmental adaptation via long-distance signaling since several miRNAs are transported between the shoot and roots in response to various soil nutrient changes. Leguminous plants adopt a shoot-mediated long-distance signaling system to maintain their mutualism with symbiotic nitrogen-fixing rhizobia by optimizing the number of symbiotic organs and root nodules. Recently, the involvement and importance of shoot-derived miR2111 in regulating nodule numbers have become evident. Shoot-derived miR2111 can systemically enhance rhizobial infection, and its accumulation is quickly suppressed in response to rhizobial inoculation and high-concentration nitrate application. In this mini-review, we briefly summarize the recent progress on the systemic optimization of nodulation in response to external environments, with a focus on systemic regulation via miR2111.

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The Fine Structure of Phloem Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119867 ◽

1985 ◽

Vol 43 ◽

pp. 632-635

Author(s):

James Cronshaw

Keyword(s):

Structural Studies ◽

High Concentration ◽

Long Distance ◽

Phloem Tissue ◽

Sieve Elements ◽

Long Distance Transport ◽

P Protein ◽

Companion Cells ◽

Electron Microscopical ◽

Distance Transport

Long distance transport in plants takes place in phloem tissue which has characteristic cells, the sieve elements. At maturity these cells have sieve areas in their end walls with specialized perforations. They are associated with companion cells, parenchyma cells, and in some species, with transfer cells. The protoplast of the functioning sieve element contains a high concentration of sugar, and consequently a high hydrostatic pressure, which makes it extremely difficult to fix mature sieve elements for electron microscopical observation without the formation of surge artifacts. Despite many structural studies which have attempted to prevent surge artifacts, several features of mature sieve elements, such as the distribution of P-protein and the nature of the contents of the sieve area pores, remain controversial.

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Popliteal entrapment syndrome and age

VASA ◽

10.1024/0301-1526/a000201 ◽

2012 ◽

Vol 41 (4) ◽

pp. 262-268 ◽

Cited By ~ 3

Author(s):

Schweizer ◽

Hügli ◽

Koella ◽

Jeanneret

Keyword(s):

Risk Factors ◽

Leg Pain ◽

Walking Distance ◽

Therapeutic Approaches ◽

Long Distance ◽

Entrapment Syndrome ◽

Long Distance Running ◽

Popliteal Entrapment ◽

Popliteal Entrapment Syndrome ◽

Atherosclerotic Risk Factors

On the occasion of diagnosing a popliteal entrapment syndrome in a 59-year old man with no cardiovascular risk factors, who developed acute ischemic leg pain during long distance running, we give an overview on this entity with emphasis on patientsage. The different types of the popliteal artery compression syndrome are summarized. The diagnostic and therapeutic approaches are discussed. The most important clinical sign of a popliteal entrapment syndrome is the lack of atherosclerotic risk factors in patients with limited walking distance. Not only in young athletes but also in patients more than 50 years old the popliteal entrapment syndrome has to be taken into account.

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Attachment Styles, Physical Proximity, and Relational Satisfaction

Aviation Psychology and Applied Human Factors ◽

10.1027/2192-0923/a000062 ◽

2014 ◽

Vol 4 (2) ◽

pp. 106-112

Author(s):

Anita Shrivastava ◽

Andrea Burianova

Keyword(s):

Attachment Styles ◽

Romantic Relationship ◽

Distinct Type ◽

Relational Satisfaction ◽

Long Distance ◽

Avoidant Attachment ◽

Geographic Separation ◽

Relationship Of ◽

Attachment Dimensions

This study aimed to explore the relationships between attachment styles, proximity, and relational satisfaction. This was achieved by assessing a distinct type of long distance romantic relationship of flying crews, compared with proximal (non-flying crew) romantic relationships. The responses of 139 expatriate professionals revealed significant associations between proximity and anxious and avoidant attachment dimensions. The role of the avoidant dimension in comparison with that of the anxious dimension was found to be a significant predictor of relational satisfaction. This study contributes significantly toward addressing the role of proximity and attachment in relational satisfaction in a new context of geographic separation.

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