Abstract: A semiconductor device in which a circuit and a battery are efficiently stored is provided. In the semiconductor device, a first transistor, a second transistor, and a secondary battery are provided over one substrate. A channel region of the second transistor includes an oxide semiconductor. The secondary battery includes a solid electrolyte, and can be fabricated by a semiconductor manufacturing process. The substrate may be a semiconductor substrate or a flexible substrate. The secondary battery has a function of being wirelessly charged.

Abstract: To support preparation of a document with consistency.

Abstract: Text is generated from an object. Text is generated from a first object. The first object includes a second object and a third object. A step of detecting coordinate data of the second object is included. A step of detecting coordinate data of the third object is included. A step of extracting positional relation between the second object and the third object from coordinate data is included. A step of converting the extracted positional relation into graph data is included. A step of generating text about the positional relation between the second object and the third object from graph data is included.

Abstract: A proofreading system that allows a user to easily judge whether or not there is an error in writing or the like. A proofreading method using a comparison image group obtained by dividing a sentence included in a comparison document group into a plurality of first terms and converting the first terms into images is provided. Specifically, first, a sentence included in a designated document is divided into a plurality of second terms, and the appearance frequency in the comparison document group of the plurality of second terms are obtained. Next, the second term with the appearance frequency lower than or equal to a threshold value of the plurality of second terms are imaged to obtain a verification image. After that, similarity degrees between the verification image and comparison images included in the comparison image group are obtained, and the first term represented by the comparison image with the highest similarity degree of the comparison images is presented.

Abstract: A hydrothermal synthesis for LiFePO4 is provided. First, each raw material solution is prepared using a degassed water in advance, second, those solution are mixed by dripping in a fixed order, and then those materials are reacted in a hydrothermal synthesis, so that LiFePO4 is obtained in a predesigned form.

Abstract: A display device having a photosensing function is provided. A display device having a biometric authentication function typified by fingerprint authentication is provided. A display device having a touch panel function and a biometric authentication function is provided. The display device includes a first substrate, a light guide plate, a first light-emitting element, a second light-emitting element, and a light-receiving element. The first substrate and the light guide plate are provided to face each other. The first light-emitting element and the light-receiving element are provided between the first substrate and the light guide plate. The first light-emitting element has a function of emitting first light through the light guide plate. The second light-emitting element has a function of emitting second light to a side surface of the light guide plate.

Abstract: Provided are a voucher verification method and a voucher verification system for automatically checking agreement between a voucher and accounting data. A processing portion receives accounting data, voucher image data, and text data, extracts a local image feature value from the voucher image data, generates, using a learned determination model, a first vector based on the accounting data and a second vector based on the local image feature value and the text data, calculates similarity between the first vector and the second vector, determines whether the accounting data agrees with the voucher using the calculated similarity, and outputs a determination result. Note that the text data is data extracted from the voucher image data by optical character recognition.

Abstract: A document reading comprehension support system which presents information necessary for a user with high accuracy is provided. A reading comprehension support system which receives a designated document; creates a first graph representing a structure of the designated document with words or phrases contained in the designated document; outputs two or more words or phrases contained in the first graph; receives a plurality of designated words or phrases from the output words or phrases; searches the first graph with the plurality of designated words or phrases; and outputs a search result, is provided. As the search result, at least a second graph representing a shortest path between any two of the plurality of designated words or phrases in the first graph can be output. The shortest path is a path connecting any two of the plurality of designated words or phrases through at least one complementary word or phrase.

Abstract: A semiconductor device in which a circuit and a battery are efficiently stored is provided. In the semiconductor device, a first transistor, a second transistor, and a secondary battery are provided over one substrate. A channel region of the second transistor includes an oxide semiconductor. The secondary battery includes a solid electrolyte, and can be fabricated by a semiconductor manufacturing process. The substrate may be a semiconductor substrate or a flexible substrate. The secondary battery has a function of being wirelessly charged.

Abstract: Described herein is a positive electrode comprising an active material particle, an acetylene black particle and net-like graphene. The positive electrode can be used in a battery.

Abstract: A semiconductor device in which a circuit and a power storage element are efficiently placed is provided. The semiconductor device includes a first transistor, a second transistor, and an electric double-layer capacitor. The first transistor, the second transistor, and the electric double-layer capacitor are provided over one substrate. A band gap of a semiconductor constituting a channel region of the second transistor is wider than a band gap of a semiconductor constituting a channel region of the first transistor. The electric double-layer capacitor includes a solid electrolyte.

Abstract: A secondary battery in which graphite that is an active material can occlude and release lithium efficiently is provided. Further, a highly reliable secondary battery in which the amount of lithium inserted and extracted into/from graphite that is an active material is prevented from varying is provided. The secondary battery includes a negative electrode including a current collector and graphite provided over the current collector, and a positive electrode. The graphite includes a plurality of graphene layers. Surfaces of the plurality of graphene layers are provided substantially along the direction of an electric field generated between the positive electrode and the negative electrode.

Abstract: A document retrieval system retrieving a document with the concept of the document taken into account is provided. The system includes a processing portion and the processing portion creates a retrieval graph from a retrieval composition. The retrieval graph includes first to m-th retrieval local graphs (m is an integer of greater than or equal to 1), and the retrieval local graphs are each constituted by two nodes and one edge. The processing portion performs retrieval of first to m-th sentences on a reference document. The i-th sentence (i is an integer of greater than or equal to 1 and less than or equal to m) includes one of the two nodes in the i-th retrieval local graph or a related term or a hyponym of the one of the two nodes; the other of the two nodes in the i-th retrieval local graph or a related term or a hyponym of the other of the two nodes; and the edge in the i-th retrieval local graph or a related term or a hyponym of the edge.

Abstract: A hydrothermal synthesis for LiFePO4 is provided. First, each raw material solution is prepared using a degassed water in advance, second, those solution are mixed by dripping in a fixed order, and then those materials are reacted in a hydrothermal synthesis, so that LiFePO4 is obtained in a predesigned form.

Abstract: A highly accurate document search, particularly a search for a document relating to intellectual property, is achieved with an easy input method. A document search system includes a processing portion. The processing portion has a function of extracting a keyword included in text data, a function of extracting a related term of the keyword from words included in a plurality of pieces of first reference text analysis data, a function of giving a weight to each of the keyword and the related term, a function of giving a score to each of a plurality of pieces of second reference text analysis data on the basis of the weight, a function of ranking the plurality of pieces of second reference text analysis data on the basis of the score to generate ranking data, and a function of outputting the ranking data.

Abstract: A decrease in the capacity of a power storage device is inhibited by adjusting or reducing imbalance in the amount of inserted and extracted carrier ions between positive and negative electrodes, which is caused by decomposition of an electrolyte solution of the negative electrode. Further, the capacity of the power storage device can be restored. Furthermore, impurities in the electrolyte solution can be decomposed with the use of the third electrode. A power storage device including positive and negative electrodes, an electrolyte, and a third electrode is provided. The third electrode has an adequate electrostatic capacitance. The third electrode can include a material with a large surface area. In addition, a method for charging the power storage device including the steps of performing charging by applying a current between the positive and negative electrodes, and performing additional applying a current between the third electrode and the negative electrode is provided.

Abstract: A secondary battery in which graphite that is an active material can occlude and release lithium efficiently is provided. Further, a highly reliable secondary battery in which the amount of lithium inserted and extracted into/from graphite that is an active material is prevented from varying is provided. The secondary battery includes a negative electrode including a current collector and graphite provided over the current collector, and a positive electrode. The graphite includes a plurality of graphene layers. Surfaces of the plurality of graphene layers are provided substantially along the direction of an electric field generated between the positive electrode and the negative electrode.

Abstract: An object is to suppress electrochemical decomposition of an electrolyte solution and the like at a negative electrode in a lithium ion battery or a lithium ion capacitor; thus, irreversible capacity is reduced, cycle performance is improved, or operating temperature range is extended. A negative electrode for a power storage device including a negative electrode current collector, a negative electrode active material layer which is over the negative electrode current collector and includes a plurality of particles of a negative electrode active material, and a film covering part of the negative electrode active material. The film has an insulating property and lithium ion conductivity.

Abstract: To provide a lithium-ion storage battery or electronic device that is flexible and highly safe. One embodiment of the present invention is a flexible storage battery including a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode, an exterior body that surrounds the positive electrode, the negative electrode, and the separator, and a wiring provided along the exterior body. At least part of the wiring is more easily breakable by deformation than the exterior body. The wiring is more vulnerable to deformation than the exterior body and thus damaged earlier than the exterior body. Damage to the wiring is detected and an alert is sent to a user; thus, the use of the storage battery can be stopped before the exterior body is damaged.

Abstract: Disclosed is a power storage unit which can safely operate over a wide temperature range. The power storage unit includes: a power storage device; a heater for heating the power storage device; a temperature sensor for sensing the temperature of the power storage device; and a control circuit configured to inhibit charge of the power storage device when its temperature is lower than a first temperature or higher than a second temperature. The first temperature is exemplified by a temperature which allows the formation of a dendrite over a negative electrode of the power storage device, whereas the second temperature is exemplified by a temperature which causes decomposition of a passivating film formed over a surface of a negative electrode active material.