著者
平川 俊介 案部 雄一郎 山下 珠希 内野 隆一郎 丸田 英基 才本 明秀 石松 隆和
出版者
日本法科学技術学会
雑誌
日本法科学技術学会誌 (ISSN:18801323)
巻号頁・発行日
vol.20, no.2, pp.125-140, 2015 (Released:2015-07-17)
参考文献数
15

Handgun bullets fired toward the windshield of an automobile sometimes ricochets. In such a case, we must estimate the type of bullet and direction of shooting from the damaged windshield. The purpose of this study is to obtain a method to estimate the fired direction of a handgun bullet from the fractured windshield. We test fired bullets to an automobile windshield with various incidence angles. The thickness of the windshield is slightly different from model to model of the automobiles. In the beginning, we examined the strength of the automobile windshield of various car models. First, we examined the static failure strength of the windshield by an indentation test. In this test, fracture load and the amount of indentation were measured on windshield samples cut from ten models of Japanese automobiles. Next, we test fired a handgun in order to examine the relation between the trajectory of a bullet and the collision marks on the windshield. The cartridges used in these test firings were 38SPL. lead round nose (LRN) bullet and full metal cased (FMC) bullet. In the results of static indentation test for different car models, there was found to be almost no differences in the relationship between fracture load and indentation depth. With the LRN bullet, bullets perforated the windshield when the incidence angle was less than 45 degrees and ricocheted when the incidence angle was greater than 60 degrees. In these cases, a characteristic damage was left on the windshield. On the other hand, FMC bullets of 38SPL. perforated the windshield when the incidence angle was less than 60 degrees and ricocheted when the incidence angle was greater than 70 degrees. Based on these results, we proposed a method to estimate the direction of shooting in criminal cases in which a bullet was fired on an automobile windshield.
著者
平川 俊介 案部 雄一郎 山下 珠希 内野 隆一郎 丸田 英基 才本 明秀 石松 隆和
出版者
日本法科学技術学会
雑誌
日本法科学技術学会誌 (ISSN:18801323)
巻号頁・発行日
pp.687, (Released:2015-05-08)
参考文献数
15

Handgun bullets fired toward the windshield of an automobile sometimes ricochets. In such a case, we must estimate the type of bullet and direction of shooting from the damaged windshield. The purpose of this study is to obtain a method to estimate the fired direction of a handgun bullet from the fractured windshield. We test fired bullets to an automobile windshield with various incidence angles. The thickness of the windshield is slightly different from model to model of the automobiles. In the beginning, we examined the strength of the automobile windshield of various car models. First, we examined the static failure strength of the windshield by an indentation test. In this test, fracture load and the amount of indentation were measured on windshield samples cut from ten models of Japanese automobiles. Next, we test fired a handgun in order to examine the relation between the trajectory of a bullet and the collision marks on the windshield. The cartridges used in these test firings were 38SPL. lead round nose (LRN) bullet and full metal cased (FMC) bullet. In the results of static indentation test for different car models, there was found to be almost no differences in the relationship between fracture load and indentation depth. With the LRN bullet, bullets perforated the windshield when the incidence angle was less than 45 degrees and ricocheted when the incidence angle was greater than 60 degrees. In these cases, a characteristic damage was left on the windshield. On the other hand, FMC bullets of 38SPL. perforated the windshield when the incidence angle was less than 60 degrees and ricocheted when the incidence angle was greater than 70 degrees. Based on these results, we proposed a method to estimate the direction of shooting in criminal cases in which a bullet was fired on an automobile windshield.
著者
本村 文孝 今井 康文 才本 明秀
出版者
一般社団法人 日本機械学会
雑誌
M&M材料力学カンファレンス
巻号頁・発行日
vol.2008, pp._GS0605-1_-_GS0605-2_, 2008
被引用文献数
2

炭酸ガスレーザを加熱源とするガラス板厚50μmの熱応力割断において,板厚をパラメータに含む板表面からの熱伝達による放熱を考慮した有限要素法を用いた3次元および2次元熱応力解析をおこなった.3次元解析では,表面発熱に起因する面外変形の拘束は応力拡大係数に影響しないことがわかった.また2次元解析にて,任意の熱源中心位置に対して熱源後方にあるき裂先端位置の応力拡大係数を評価することで,熱伝達による放熱が大きくなると,熱応力割断中のき裂進展挙動の安定性が増すことが示唆された.
著者
平川 俊介 案部 雄一郎 山下 珠希 内野 隆一郎 丸田 英基 才本 明秀 石松 隆和
出版者
Japanese Association of Forensic Science and Technology
雑誌
日本法科学技術学会誌 (ISSN:18801323)
巻号頁・発行日
2015

Handgun bullets fired toward the windshield of an automobile sometimes ricochets. In such a case, we must estimate the type of bullet and direction of shooting from the damaged windshield. The purpose of this study is to obtain a method to estimate the fired direction of a handgun bullet from the fractured windshield. We test fired bullets to an automobile windshield with various incidence angles. The thickness of the windshield is slightly different from model to model of the automobiles. In the beginning, we examined the strength of the automobile windshield of various car models. First, we examined the static failure strength of the windshield by an indentation test. In this test, fracture load and the amount of indentation were measured on windshield samples cut from ten models of Japanese automobiles. Next, we test fired a handgun in order to examine the relation between the trajectory of a bullet and the collision marks on the windshield. The cartridges used in these test firings were 38SPL. lead round nose (LRN) bullet and full metal cased (FMC) bullet. In the results of static indentation test for different car models, there was found to be almost no differences in the relationship between fracture load and indentation depth. With the LRN bullet, bullets perforated the windshield when the incidence angle was less than 45 degrees and ricocheted when the incidence angle was greater than 60 degrees. In these cases, a characteristic damage was left on the windshield. On the other hand, FMC bullets of 38SPL. perforated the windshield when the incidence angle was less than 60 degrees and ricocheted when the incidence angle was greater than 70 degrees. Based on these results, we proposed a method to estimate the direction of shooting in criminal cases in which a bullet was fired on an automobile windshield.<br>
著者
松田 浩 木村 吉郎 河村 進一 森田 千尋 才本 明秀 森山 雅雄 出水 亨 牧野 高平 豊岡 了 上半 文昭
出版者
長崎大学
雑誌
基盤研究(B)
巻号頁・発行日
2009

(1)非接触全視野非破壊試験法の開発とその応用:レーザシェアログラフィを用いた欠陥検知への有効性について検討した。また、超高速度カメラを用いた動的変位計測システムによる振動計測法の有効性を確認した。(2)常時微動計測に基づく構造同定及び健全度評価への応用:耐震補強前後の実橋脚を対象として、レーザドップラ速度計による振動試験とFE解析から振動モード同定を実施した。補強前後の固有振動数の変化を実振動計測および振動解析で確認することができた。