A lighting device, such as a two-wire lighting control device, may include a controllably conductive device and a control circuit. The controllably conductive device may supply an AC line voltage to a load in response to a dive signal such that the controllable conductive device is non-conductive for a first duration of time and conductive for a second duration of time within a half-cycle of the AC line voltage. The control circuit may receive a signal from the controllably conductive device that represents a voltage developed across the controllable conductive device during the first duration of time. The control circuit may generate a sine-wave-shaped signal that complements the voltage developed across the controllably conductive device during the second duration of time. The control circuit may also filter the signal from the controllably conductive device during the first duration of time and the sine-wave-shaped signal during the second duration of time.

A lighting apparatus includes a top cover, a bottom cover, a light passing cover, a battery, a power circuit, a power switch and a light source plate. The top cover has an opening part for defining a light opening. The bottom cover is fixed to the top cover forming a containing space. The light passing cover has a larger diameter than the light opening. A peripheral edge of the light passing cover engages an inner surface of the opening part of the top cover. The battery is stored in the container space. The power circuit is connected to the battery for providing a current to the LED modules of the light source plate. The power switch is connected to the power circuit to control the LED modules. The light source plate has a top side mounted with multiple LED modules.

A lighting apparatus includes a top cover, a bottom cover, a light passing cover, a battery, a power circuit, a power switch and a light source plate. The top cover has an opening part for defining a light opening. The bottom cover is fixed to the top cover forming a containing space. The light passing cover has a larger diameter than the light opening. A peripheral edge of the light passing cover engages an inner surface of the opening part of the top cover. The battery is stored in the container space. The power circuit is connected to the battery for providing a current to the LED modules of the light source plate. The power switch is connected to the power circuit to control the LED modules. The light source plate has a top side mounted with multiple LED modules.

A plant disease control method and a plant disease control apparatus that can irradiate a plant under cultivation with an appropriate amount of near-infrared light to obtain an effect of controlling diseases while efficiently using light energy. The plant under cultivation is irradiated with the near-infrared light including a wavelength set within a wavelength range of 800 to 1000 nm so as to satisfy all following Equations 1 to 3 where X is an irradiance (W/m.sup.2) and Y is an irradiation time (second), so that the effect of controlling diseases can be obtained.

644893X.sup.−1.873≥Y≥5901.9X.sup.−1.856  Equation 1:

X≥1  Equation 2:

Y≥0.01  Equation 3:

A plant disease control method and a plant disease control apparatus that can irradiate a plant under cultivation with an appropriate amount of near-infrared light to obtain an effect of controlling diseases while efficiently using light energy. The plant under cultivation is irradiated with the near-infrared light including a wavelength set within a wavelength range of 800 to 1000 nm so as to satisfy all following Equations 1 to 3 where X is an irradiance (W/m.sup.2) and Y is an irradiation time (second), so that the effect of controlling diseases can be obtained.

644893X.sup.−1.873≥Y≥5901.9X.sup.−1.856  Equation 1:

X≥1  Equation 2:

Y≥0.01  Equation 3:

A computer-implemented method of lighting control is disclosed. The method includes identifying a group of people according to a relationship between or among the people that indicates the people are likely to regularly reside in a common location, determining a goal for the group of people for aligning circadian cycles of people in the group of people, determining a time and manner for altering ambient light at the common location in a manner to achieve the determined goal; and generating control signals to cause ambient lighting appliances at the common location to alter their performance according to the determined time and manner to achieve the determined goal.

A computer-implemented method of lighting control is disclosed. The method includes identifying a group of people according to a relationship between or among the people that indicates the people are likely to regularly reside in a common location, determining a goal for the group of people for aligning circadian cycles of people in the group of people, determining a time and manner for altering ambient light at the common location in a manner to achieve the determined goal; and generating control signals to cause ambient lighting appliances at the common location to alter their performance according to the determined time and manner to achieve the determined goal.

In a first light emission control device, a clock signal is generated, and after a first driving sequence starts to be performed in which the respective states of light-emitting elements in a first light-emitting element array are sequentially switched synchronously with the clock signal, at a particular time point a characteristic of the clock signal is changed from a first characteristic to a second characteristic. After the change, in a second light emission control device, a second driving sequence is performed in which the respective states of light-emitting elements in a second light-emitting element array are sequentially switched synchronously with the clock signal.

In a first light emission control device, a clock signal is generated, and after a first driving sequence starts to be performed in which the respective states of light-emitting elements in a first light-emitting element array are sequentially switched synchronously with the clock signal, at a particular time point a characteristic of the clock signal is changed from a first characteristic to a second characteristic. After the change, in a second light emission control device, a second driving sequence is performed in which the respective states of light-emitting elements in a second light-emitting element array are sequentially switched synchronously with the clock signal.

A power management system for a lighting circuit may include a grid shifting controller that includes a processor and a connection to an external power source. The power management system may also include a communication interface associated with the grid shifting controller. The grid shifting controller may be configured to provide control information to a processor of at least one grid shifting electrical fixture over the communication interface, the control information being configured to direct the at least one grid shifting electrical fixture on the use of power from the external power source and an energy storage device associated with the at least one grid shifting electrical fixture.