Abstract: A DC power distribution system for performing DC power distribution from a power distribution side base to one or more power reception side bases via a power distribution network includes measuring instruments provided at the power distribution side base and at the one or more power reception side bases, and a control device, in which the control device includes an operation unit that acquires a voltage value and a current value measured by the measuring instrument and calculates an output side power sum that is a sum of power output from the power distribution side base, a power reception side power sum that is a sum of power input to the one or more power reception side bases, and a loss sum between the power distribution side base and the one or more power reception side bases, and a control unit that detects an abnormality in the distribution network by comparing the output side power sum with a total sum of the power reception side power sum and the loss sum.

Abstract: A connection direct-current power distribution system including a first direct-current power distribution system having a first voltage range and a second direct-current power distribution system having a voltage range narrower than the first voltage range includes a switch and a converter between the first direct-current power distribution system and the second direct-current power distribution system, and the switch is caused to enter a connected state, and power from a first storage battery in the first direct-current power distribution system is supplied to the second direct-current power distribution system via the converter configured to adjust a voltage of the power.

Abstract: A direct-current power distribution system for distributing power from a power supply device to a load device via a power distribution network includes a measuring instrument included in the power distribution network, and a control device including a determination unit configured to acquire a voltage value and a current value measured by the measuring instrument, and determine an operating state in the direct-current power distribution system on the basis of a waveform indicating change in the voltage value and a waveform indicating change in the current value.

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream having an Fe concentration of 76.0 at % or more and less than 82.9 at % is 100° C. or more higher than the melting point, spraying primary cooling water at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream from one direction and an impact direction on the molten metal stream from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+100° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

Abstract: The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1): 0.3×Cu %+3×Mo %?2.7??(1).

Abstract: A lightning damage prediction apparatus that predicts a risk of a failure of access equipment due to a lightning strike is provided. A regression equation representing a relationship between a lightning strike density for each section in a prediction target area, an equipment density for each section of components of a plurality of types constituting equipment, and a lightning damage failure density for each section of the equipment or the component, corresponding to a first period in the past, is generated, and a lightning damage failure density for each section of a prediction target area corresponding to a second period is predicted on the basis of a lightning strike density and an equipment density for each section in the prediction target area corresponding to the second period that is a prediction target, and the regression equation.

Abstract: The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1): 0.3×Cu %+3×Mo %?2.7??(1).

Abstract: Provided is alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, or Si. The alloyed steel powder includes iron-based alloy containing Mo, in which Mo content is 0.4 mass % to 1.8 mass %, a weight-based median size D50 is 40 ?m or more, and among particles contained in the alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

Abstract: Disclosed is a mixed powder for powder metallurgy including: (a) an iron-based powder containing Si in an amount of 0 mass % to 0.2 mass % and Mn in an amount of 0 mass % to 0.4 mass %, with the balance being Fe and inevitable impurities; and (b) an alloyed steel powder containing Mo in an amount of 0.3 mass % to 4.5 mass %, Si in an amount of 0 mass % to 0.2 mass %, and Mn in an amount of 0 mass % to 0.4 mass %, with the balance being Fe and inevitable impurities, wherein a ratio of (b) the alloyed steel powder to a total of (a) the iron-based powder and (b) the alloyed steel powder is from 50 mass % to 90 mass %, and a ratio of Mo to the total of (a) the iron-based powder and (b) the alloyed steel powder is 0.20 mass % or more and less than 2.20 mass %.

Abstract: A fuse with a frequency separation function includes an input port portion, an output port portion, a first transmitting portion between the input port portion and the output port portion, the first transmitting portion configured to transmit a lightning surge current entering the input port portion and guide the lightning surge current to the output port portion, a second transmitting portion between the input port portion and the output port portion, the second transmitting portion configured to be capable of transmitting a normal current and an abnormal current entering the input port portion, and a melting mechanism portion which is provided between the second transmitting portion and the input port portion or between the second transmitting portion and the output port portion, the melting mechanism configured not to melt and break when the normal current passes, and configured to melt and break when the abnormal current passes.

Abstract: Disclosed is a partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, and Si. A partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility that includes an iron-based powder and Mo diffusionally adhered to a surface of the iron-based powder, in which Mo content is 0.2 mass % to 2.0 mass %, a weight-based median diameter D50 is 40 ?m or more, and among particles contained in the partially diffusion-alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

Abstract: Outdoor lightning countermeasure requiring facilities are effectively predicted. A facility information analysis unit 121 reads lightning strike information, lightning damage failure information on facilities when lightning strikes, and facility information from a recording unit 110 to extract facility information on facilities in which a lightning damage failure has occurred and facility information on facilities in which a lightning damage failure has not occurred. A parameter analysis unit 122 parameterizes items associated with the spots of the extracted facility information in which a lightning damage failure has occurred. A prediction model construction unit 131 performs the machine learning of the parameterized facility information to generate a prediction model that outputs the possibilities of the occurrence of a lightning damage failure in facilities when lightning strikes.

Abstract: A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream having an Fe concentration of 76.0 at % or more and less than 82.9 at % is 100° C. or more higher than the melting point, spraying primary cooling water at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream from one direction and an impact direction on the molten metal stream from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+100° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

Abstract: Provided is alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, or Si. The alloyed steel powder includes iron-based alloy containing Mo, in which Mo content is 0.4 mass % to 1.8 mass %, a weight-based median size D50 is 40 ?m or more, and among particles contained in the alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

Abstract: Disclosed is a partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility without containing Ni, Cr, and Si. A partially diffusion-alloyed steel powder having excellent fluidity, formability, and compressibility that includes an iron-based powder and Mo diffusionally adhered to a surface of the iron-based powder, in which Mo content is 0.2 mass % to 2.0 mass %, a weight-based median diameter D50 is 40 ?m or more, and among particles contained in the partially diffusion-alloyed steel powder, those particles having an equivalent circular diameter of 50 ?m to 200 ?m have a number average of solidity of 0.70 to 0.86, the solidity being defined as (particle cross-sectional area/envelope-inside area).

Abstract: The present disclosure relates to an iron-based prealloy powder having excellent strength and processability, and an iron-based alloy powder for powder metallurgy and a sinter-forged member using the same. The iron-based prealloy powder for powder metallurgy according to an embodiment of the present disclosure includes 0.5 to 5.0 wt % of Cu, 0.1 to 0.5 wt % of Mo, and a balance of Fe and other inevitable impurities. A Cu content (Cu %) and a Mo content (Mo %) satisfy the following Relational Equation (1): 0.3×Cu %+3×Mo %?2.7??(1).

Abstract: A lightning damage prediction apparatus that predicts a risk of a failure of access equipment due to a lightning strike is provided. A regression equation representing a relationship between a lightning strike density for each section in a prediction target area, an equipment density for each section of components of a plurality of types constituting equipment, and a lightning damage failure density for each section of the equipment or the component, corresponding to a first period in the past, is generated, and a lightning damage failure density for each section of a prediction target area corresponding to a second period is predicted on the basis of a lightning strike density and an equipment density for each section in the prediction target area corresponding to the second period that is a prediction target, and the regression equation.

Abstract: Provided is a method of manufacturing a soft magnetic dust core. The method includes: preparing coated powder including amorphous powder made of an Fe-B-Si-P-C-Cu-based alloy, an Fe-B-P-C-Cu-based alloy, an Fe-B-Si-P-Cu-based alloy, or an Fe-B-P-Cu-based alloy, with a first initial crystallization temperature Tx1 and a second initial crystallization temperature Tx2; and a coating formed on a surface of particles of the amorphous powder; applying a compacting pressure to the coated powder or a mixture of the coated powder and the amorphous powder at a temperature equal to or lower than Tx1?100 K; and heating to a maximum end-point temperature equal to or higher than Tx1?50 K and lower than Tx2 with the compacting pressure being applied.

Abstract: A fuse (1) with a frequency separation function includes an input port portion (1a), an output port portion (1b), a first transmitting portion (1c) which is provided between the input port portion and the output port portion, the first transmitting portion (1c) configured to transmit a lightning surge current entering the input port portion and guide the lightning surge current to the output port portion, a second transmitting portion (1d) which is provided between the input port portion and the output port portion, the second transmitting portion configured to be capable of transmitting a normal current and an abnormal current entering the input port portion, and a melting mechanism portion (1d-2) which is provided between the second transmitting portion and the input port portion or between the second transmitting portion and the output port portion, the melting mechanism configured not to melt and break when the normal current passes, and configured to melt and break when the abnormal current passes.

Abstract: [Object] Provided is a method for manufacturing atomized metal powder having a high amorphous material fraction by using a water atomizing method. [Solution] A method for manufacturing atomized metal powder in which atomized metal powder having an amorphous material fraction of 90% or more is obtained, the method including ejecting high-pressure water so as to collide with a molten metal stream flowing vertically downward, separating the molten metal stream into metal powder, and cooling the metal powder, in which the high-pressure water collides with the molten metal with a collision pressure of 20 MPa or higher, and in which a temperature of the molten metal and/or a temperature of the high-pressure water are controlled so that the high-pressure water is in a subcritical state or a supercritical state on a collision surface with the molten metal.