Blasting to break the rock and structure using energy of explosive is one of the important operation for civil and mining engineering. In this research some test blasting using high-speed camera, high-speed video and precis blasting system were carried out to study the generation mechanism of fly rock caused by blasting. Seven full scale test blasts in the quarry with different quantities of explosives and burden were carried out to study the flying characteristics of fly rock caused by blasting. DDA (Discontinuous Deformation Analysis) was applied for numerical simulation of full scale blasting. The results are briefly summarized as follows;
1. Initial fracture in the model experiment using the glass material was caused by the Hopkinson effect. The separated fragment, considered as a fly rock, then is accelerated in the direction of a free face by the remained stress.
2. The flight distance of fly rock generated near the minimum resistance line have longer compared with other fly rock in the mortar block experiment. The reason is considered that fly rock near the minimum resistance line was influenced easily by the impact stress and the expansion gas generated by the detonator and detonating fuse. Moreover, it was shown to be able to control the flight distance of the fly rock by applying the precise initiation method.
3. The generation situation and the flying characteristics of the fly rock generated in the bench blasting were clarified from full scale test blasting. Moreover, it was shown that DDA was able to apply for the numeric simulation of bench blasting.

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Principles and safety of fireworks as well as the database that the authors have been opened to the public are overviewed. First, chemical substances used to make fireworks are explained. Especially, oxidizers, which are solid powders including oxygen, are focused on. The reasons why the oxidants that are currently used have been selected to make fireworks are scientifically explained. Moreover, issues related to combustible substances are explained in detail. Next, the safety of fireworks is outlined. AIST has been addressing this issue for a long time. Various types of laboratory-scale sensitivity tests, evaluation tests for the hazard of spontaneous ignition, and safe production methods are explained. Finally, in “Physical Hazard Database of Chemicals,” a database developed by the authors and opened to the public, the parts related to fireworks are introduced.

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Relational Information System for Chemical Accidents Database (RISCAD) has been developed by AIST and JST. Some of the accident data contain progress flowcharts and lessons learned information. The accident progress flowcharts have been created to assist database users to have more clear understanding of what happened in the accident. As for the procedures to make the flowcharts, first, one of the analyzing team members from the RISCAD staff investigated some accident reports and made a draft progress flowchart to discuss with other members together. Then, we tried to figure out, for example, the root causes, which had not been clear yet since the accident occurred. Finally, the progress flowchart can then be updated on the website. You can also see their lessons learned information that can be helpful to prevent future accidents. In this paper, the outline and the functions of RISCAD are introduced. Also, a case study related to mechanical equipments is presented following the progress flowchart.

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構造物を発破を用いて解体する技術が, 経済性, 効率, 安全性の面で有利な工法として注目されている. 今回失敗の許されない実施工の立場から製鉄所内に残存する鉄筋コンクリート構造物を, 発破を用いて一挙倒壊させることに成功した. 本報告では耐震性にすぐれた国内の構造物に本工法を適用する際の課題を整理した上で, 特に全体計画と倒壊設計の考え方および手順を述べ, 実際の構造物への適用を通じてその妥当性を検証した. さらに実適用によって得られた新たな知見についても言及した.

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理科実験では ， 様々な化学物質を取り扱う ． その中には可燃性物質が含まれるため ， 火災 ， 爆発が発生 し ， 施設等が焼損 ， 破損することがある ． 加熱などの操作を行うために ， 裸火 ， 加熱器具などを使用する ため ， 火災 ， 爆発 ， 高温物体との接触などによって火傷などの負傷を負うことがある ． また ， 理科実験で 取り扱う化学物質の中には ， 毒性のあるものがある ． 化学反応によって ， 毒性のある化学物質が生成する ことがある ． それらの化学物質に暴露されて体調不良になり ， 救急搬送されることもある ． 火災 ， 爆発 ， 負傷 ， 体調不良などの発生防止 ， それらが発生した際の再発防止などに役立てるため ， 理科実験が関係し た火災 ， 爆発などの事例とその対策を示す ．

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Relational Information System for Chemical Accidents Database (RISCAD) has been developed by AIST and JST. Some of the accident data contain progress flowcharts and lessons learned information. The accident progress flowcharts have been created to assist database users to have more clear understanding of what happened in the accident. As for the procedures to make the flowcharts, first, one of the analyzing team members from the RISCAD staff investigated some accident reports and made a draft progress flowchart to discuss with other members together. Then, we tried to figure out, for example, the root causes, which had not been clear yet since the accident occurred. Finally, the progress flowchart can then be updated on the website. You can also see their lessons learned information that can be helpful to prevent future accidents. In this paper, the outline and the functions of RISCAD are introduced. Also, a case study related to mechanical equipments is presented following the progress flowchart.

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By the'explosion, high dense and high pressure detonation products gasses expand rapidly and extremely strong shock waves are driven. The three-dimensional simulation is executed for the propagation of the blast waves driven by TNT32kg explosion in the underground magazine. We present an effective visualization of the fireball, and the key idea for the fireball with complex surface illuminated by the black body radiation is the combination of volume rendering with iso surface rendering based on a pure ray tracing method.

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Japanese fireworks began in the Edo period. And the technology has advanced with the support by the people over time. Currently, Japanese fireworks are highly respected worldwide. I think the reason is that Japanese are creating the clear bright color and sound technology using the characteristics of aluminum powder (Al powder) well. On the other hand, severe accidents such as “mass explosion” which affect almost the entire explosives virtually instantaneously during manufacture and storage of fireworks articles including Al powder had continued until recently. It was similar in overseas. For this reason, investigation and research have been conducted at various levels, such as international, national and industrial levels, and regulations had been also tightened. International regulation on transportation of dangerous goods including fireworks should follow the regulation called "UN Recommendations". By these investigation and researches, the regulations of fireworks were changed dramatically in 2005, and then continued to change. Additionally, ISO standards of fireworks have been developed from 2012 and published in 2017. The transport classification of fireworks should be decided by the flash composition test of UN Recommendation. This flash composition test is composed of two kinds tests, a time pressure test with 0.5g sample and DDT test with 25g one. It became clear by Japanese studies that the time pressure test overestimates due to the scale effect. It seems that the combustion behavior of Al powder at high temperature and high pressure tightly relates to mass explosion, but the actual behavior is unknown now time.

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爆発によって、爆薬は高密度・高圧力の爆轟生成ガス(火炎)となり、急激に膨張する。膨張過程で火炎表面には流体力学不安定による擾乱が成長する。火炎は黒体輻射により発光し、外光が火炎内部を通過できないために火炎表面近傍の複雑な構造が観測される。しかし火炎の膨張速度や分布範囲の実験的測定は困難である。本研究ではレイ・トレーシングを用いて３次元的に膨張する火炎の可視化を行い、火炎の膨張過程の観測を可能にした。

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構造物の解体に発破工法を用いる場合, 高爆速の爆薬が必要であること, 張り付けタイプの爆薬を用いる場合があることから騒音の制御が大きな問題である. 本研究では特殊な衝撃音である爆発音について, 砂厚, 薬量, 距離についてのパラメトリックな検討により減音材として砂を用いた場合の減音効果の特性を明らかにするとともに, それらの関係を定式化し精度の高い音圧ピーク値予測式を導いた. また実際の施工への本式の適用性についても論じた.

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各国の危険物の専門家の代表からなるOECD－IGUSの概要と危険物規制に関する国際情勢について紹介するとともに，危険物の国際化に向けての日本の対応，特に技術的課題についての実質審議の場で IGUSに向けての日本の対応と今後の課題について述べた．

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本論文は微小発破の生体応用に関する研究の第12報に相当する.
微小発破による膀胱結石破砕は, 発破法の上からも, また発破理論上からも一般岩石発破の小割発破に相当する. 小割発破には, 張り付け発破と穿孔発破とがあるが, 穿孔発破のほうが張り付け発破よりも効率良く結石を破砕することができる.
私たちは, 膀胱結石に対する穿孔発破のための電気ドリル式膀胱結石穿孔装置を開発し, 現在まで60症例の穿孔発破による膀胱結石破砕に成功した.
本報では, この膀胱結石に対する穿孔発破の基礎的理論と機器の開発ならびにその臨床応用について述べた.

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本研究では, 主として岩盤の大変形挙動解析に用いられている不連続変形法 (DDA) による倒壊シミュレーションを, 実存RC構造物の発破解体工事の倒壊設計に適用し, 適切と思われる解析結果を得た. 本手法により, 時系列的な構造系の変化すなわち倒壊過程および最終崩壊状況を予測し, 段発発破計画の設計資料としたので, その概要を報告する.

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近年，世界各地で爆薬を使ったテロ事件が頻発している．特に空港，駅などの不特定多数の人が集まる場所において一般市民を狙った事件により多くの人が犠牲になっている．また，これまでの検出機器では検出しにくい新型爆薬が使われる傾向があり，かつ誰でも容易に製造できるような爆薬による事件が多くなっているのが特徴的である． 本研究はこれらの爆薬を空港や駅などの入口で素早く検知し，そして検出された爆発物を安全に保管・処理できるシステムを開発することを目的としている．すなわち爆薬の超高感度検出装置と，検出した爆薬の処理装置を統合した爆発物検出・処理統合システムを爆薬の学理に基づき開発する．爆薬検出・処理技術の基盤となる爆薬の分子構造論的な特徴と起爆機構を化学反応論の立場から明らかにし，爆薬の同定法，爆薬類の不爆化・威力低減化の手法を確立しようとするものである．

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