受験番号：32IPE032

問１
1. An apparatus for calculating a cardiothoracic ratio, the apparatus being configured tocalculate a cardiothoracic ratio based on a chest radiograph, comprising:a unit for estimating a measurement position, the unit being configured toestimate a position for a right edge of a lung, a position for a left edge of the lung, aposition for a right edge of a heart, and a position for a left edge of the heart in the chest
radiograph; anda unit for calculating a cardiothoracic ratio, the unit being configured tocalculate a cardiothoracic ratio based on the estimated position for the right edge of thelung, the estimated position for the left edge of the lung, the estimated position for theright edge of the heart, and the estimated position for the left edge of the heart, wherein
the unit for estimating a measurement position divides the chest radiography
into a plurality of regions in a horizontal direction, and in each region in the horizontal
direction, the unit for estimating a measurement position detects a candidate for theright edge of the lung, and a candidate for the left edge of the lung based on a pixel
value, and detects a candidate for the right edge of the heart, and a candidate for theleft edge of the heart based on a derivative value of the pixel value in the horizontal
direction, andthe unit for estimating a measurement position further extracts a particularregion in the horizontal direction based on a distance between a lung midpoint
determined by the candidate for the right edge of the lung and the candidate for the leftedge of the lung, and a heart midpoint determined by the candidate for the right edge ofthe heart and the candidate for the left edge of the heart, or based on a ratio of thedistance with respect to a lung width determined by the candidate for the right edge ofthe lung and the candidate for the left edge of the lung, and estimates the candidate forthe right edge of the lung, the candidate for the left edge of the lung, the candidate forthe right edge of the heart, and the candidate for the left edge of the heart in theextracted region in the horizontal direction to be the position for the right edge of thelung, the position for the left edge of the lung, the position for the right edge of the heart,and the position for the left edge of the heart, respectively.
2. The apparatus for calculating a cardiothoracic ratio, according to claim 1, wherein
when larger X-ray transmittance leads to a larger pixel value,
the unit for estimating a measurement position detects a position with a lowest

pixel value as a candidate for the right edge of the lung in a region within apredetermined range from a right edge of the region in the horizontal direction, andthe unit for estimating a measurement position detects a position with a lowestpixel value as a candidate for the left edge of the lung in a region within apredetermined range from a left edge of the region in the horizontal direction.
3. The apparatus for calculating a cardiothoracic ratio, according to claim 1 or 2,
whereinthe unit for estimating a measurement position detects a position with aderivative value largest in a negative direction as a candidate for the right edge of theheart between the candidate for the right edge of the lung and the candidate for the leftedge of the lung in the region in the horizontal direction, andthe unit for estimating a measurement position detects a position with aderivative value largest in a positive direction as a candidate for the left edge of theheart between the candidate for the right edge of the lung and the candidate for the leftedge of the lung in the region in the horizontal direction.
問２
A technique referred to as block chain has been known conventionally. This
technique refers to a mechanism that synchronizes identical records among many nodes
on a network. When a new record is added to existing records, a block, serving as arecording unit, is successively added like a chain while inheriting the contents (hash) of
the immediately preceding block. This is why the technique is called block chain. Ingeneral, the term "block chain" may refer to a database structure having blocks
connected like a chain, but may be used in the broad sense including a mechanism
operating as a P2P network and a mechanism for authorizing transactions.

The

definition of block chain is currently unestablished. In view of this, the term "blockchain" is to be employed herein when used in the former narrow meaning, whereas theterm "block chain technique" is to be employed herein when used in the latter broad
meaning for the purpose of avoiding confusion between those meanings.
The block chain technique has many advantages including the absence ofdowntime, difficulty in tampering, and its low cost. Thus, the block chain technique isjust beginning to receive attention as a method for managing information regarding not
only virtual currencies such as Bitcoin and its derivative currencies but also various
assets as transactions. Non-Patent Literature 1, for example, describes that blockchain that can play an important role in establishing reliability is used for certifying theexistence or identity of various documents.
The block chain technique is mainly divided into a public node method and aprivate node method. According to the public node method, anyone can participate inas a node on a network. According to the private node method, however, only a person
permitted as a node on a network can participate in.
問３
During Occurrence of Backfire
If the backfire R is emitted from the burner element 15 in the burner 100, thethermally-expandable member 22 thermally expands in an inner peripheral direction
due to the heat of the backfire R as shown in FIG. 3B, thus forming athermally-expandable member 222 (22) with the opening 22H being closed.
Consequently, the closure of the opening 22H in the thermally-expandable
member 222 (22) prevents the heat of the backfire R and ultraviolet rays emitted by theflame F produced by the burner element 15 from reaching the flame detection sensor 23.
A controller (not shown) in this embodiment is configured, for example, todetermine that the burner 100 is operating properly when the flame detection sensor 23
detects the ultraviolet rays L, and determine that backfire or accidental fire hasoccurred when an amount of ultraviolet rays L detected by the flame detection sensor 23
is smaller than or equal to a set threshold value (including zero).
Thus, when the burner 100 causes accidental fire and thereby emits noultraviolet rays L, when the thermally-expansive member 22 thermally expands asshown in FIG. 3B and thus no ultraviolet rays L are detected by the flame detection
sensor 23, or when the amount of the detected ultraviolet rays L is smaller than orequal to the threshold value, it is determined that the burner 100 has accidental fire or
backfire.