Potens per accidens sine accidentibus: Ockham on Material Substances and Their Essential Powers

Medieval scholastics share a commitment to a substance-accident ontology and to an analysis of efficient causation in which agents act in virtue of their powers. Given these commitments, it seems ready-made which entities are the agents or powers: substances are agents and their accidents powers. William of Ockham, however, offers a rather different analysis concerning material substances and their essential powers, which this article explores. The article first examines Ockham’s account of propria and his reasons for claiming that a material substance is essentially powerful sine accidentibus. However, the article subsequently argues that, given Ockham’s reductionism about material substance, only substantial forms – never substances – are truly agents and powers. Thus, a material substance is essentially powerful but only by courtesy – per accidens, as Ockham calls it – because it has a non-identical part, its substantial form, which does all the causal work by itself, per se.

ISLAM DAN PENDIDIKAN: STUDI PEMIKIRAN MOHAMMAD HATTA

This paper is a literature study using a historical approach that takes primary and secondary data from the writings of Mohammad Hatta, autobiography, and writing about Mohammad Hatta. Hatta was one of the important figures for the birth of the Republic of Indonesia who participated in the independence struggle. Hatta is also known as a thinker whose broad spectrum includes economics, philosophy, ideology, politics, social, culture, religion, and education. Religion became an integral part of Hatta since childhood. Islam for Hatta became the basis of personal values ​​that guide behavior. Likewise, religion has a role in developing social, political, and social life. Hatta's Islamic thought style was more substantially patterned, rather than formative. Education was also an identical part of Hatta since the struggle for Indonesian independence. The political task in the main colony is to educate the people to understand their duties, rights, and responsibilities so that new cadres of leaders can be born. After Indonesia's independence, the issue of education became one of the concerns of Hatta. Education for an independent country is an investment in the future of a country.

Optimal Structure Design Methodology for Compound Multiaxis Machine Tools-III - Performance Evaluation -

Compound multiaxis machine tools are developed for machining of high-value-added parts throughintegrating milling and turning operations. Due to the complexity of the configuration and the functional versatility required for a compound machine tool, machining accuracy, productivity, and return on investment (ROI) remain to be improved. Design methodology has been widely studied to design high-performance compound multiaxis machine tools. We evaluated their performance in this study, finding that a V guide effectively improves movement accuracy in the X, Y, and Z directions. Cutting tests conducted on the XY-plane, YZ-plane, and an inclined plane prove that tight circularity is achieved. Cutting cycle time for an identical part and the same part compared between conventional and new compound multiaxis machine tools showed the cutting cycle time is largely reduced. We also found that new compound multiaxis machine tools consume less electricity than a manufacturing system with equivalent productivity consisting of a 2-axis lathe and a machining center.

Optimal Structure Design Methodology for Compound Multiaxis Machine Tools-III - Performance Evaluation -

Compound multiaxis machine tools are developed for machining of high-value-added parts throughintegrating milling and turning operations. Due to the complexity of the configuration and the functional versatility required for a compound machine tool, machining accuracy, productivity, and return on investment (ROI) remain to be improved. Design methodology has been widely studied to design high-performance compound multiaxis machine tools. We evaluated their performance in this study, finding that a V guide effectively improves movement accuracy in the X, Y, and Z directions. Cutting tests conducted on the XY-plane, YZ-plane, and an inclined plane prove that tight circularity is achieved. Cutting cycle time for an identical part and the same part compared between conventional and new compound multiaxis machine tools showed the cutting cycle time is largely reduced. We also found that new compound multiaxis machine tools consume less electricity than a manufacturing system with equivalent productivity consisting of a 2-axis lathe and a machining center.

Case adaptation in PROCASE: A case-based process planning system for machining of rotational parts

This paper presents an approach for the case adaptation, especially case repairing, in a case-based process planning system: PROCASE, for machining of rotational parts. In PROCASE, a new process plan is generated by adapting an existing similar process plan from its case library. Case adaptation is a crucial issue in achieving an automated case-based process planning system. This is because, usually, an existing process plan cannot necessarily produce an exact identical part as of the desired part. Adaptation is essential to tailor this existing plan to generate a new process plan for the new part. The case adaptation in this paper comprises case modification, case simulation, and case repairing. The modifier uses the knowledge extracted from case library to edit the retrieved similar plan. The simulator plays an important role in verifying the adapted plan as well as in directing the plan repairing. The repairing rules are indexed by the error messages obtained from the simulation. With the proposed case adaptation, the system will have the capability to repair the erroneous plans to achieve an automated and intelligent process planning system. This paper will first briefly introduce the case representation and case retrieval in PROCASE. Then the rest of the paper is dedicated to the case adaptation.

Tetramethylthiuram Disulfide Vulcanization of Extracted Rubber. V. Low Molecular Products and the Mechanism of Zinc Oxide Activation

The essential features of TMTD vulcanization, as revealed by compounding tudies, were discussed in Part I of this series. Thus, TMTM, a product of TMTD vulcanization, and an active accelerator of sulfur vulcanization, was found to be an inhibitor, and ZnDMDC, a main product of TMTD vulcanization, in the presence of ZnO was found to be devoid of activating properties. As a replacement of ZnO, which is a potent activator, ZnDMDC displayed only mild activating effects. Zinc palmitate was even more potent than ZnO. Zinc sulfide was somewhat less active than ZnO. Palmitic acid and DMADC had little or no effect on the cure. The second paper reported that TMTD could be prepared in good yield by the reaction of TMTM with sulfur and also, as a result of radiosulfur techniques, that the four sulfur atoms in the TMTD molecule are chemically identical. Part II also reported that ZnO reacted with TMTD to form sulfur and ZnDMDC in good yield. Other reactions of TMTD were discussed. Part III, in presenting a short-path distillation technique for studying vulcanizates, reported that the nearly complete removal of zinc from the TMTD vulcanizate is not accompanied by devulcanization. Part IV reported on the behavior of rubber as an acid. This behavior results in the liberation of palmitic acid from zinc palmitate. From the comparison of the reaction of TMTD with acids and the reaction of rubber with TMTD, it was inferred that rubber is an OH-containing acid. Acids in the work reported were found to react rather slowly with TMTD to form dimethylamides and sulfur in good yield. The acidic nature of rubber did not seem to be great enough to contribute in any fundamental way to the vulcanization process. The present paper describes further studies of the TMTD vulcanization problem.