40 research outputs found
Reducing Print Time While Minimizing Loss in Mechanical Properties in Consumer FDM Parts
Fused deposition modeling (FDM), one of various additive manufacturing (AM) technologies, offers a useful and accessible tool for prototyping and manufacturing small volume functional parts. Polylactic acid (PLA) is among the commonly used materials for this process. This study explores the mechanical properties and print time of additively manufactured PLA with consideration to various process parameters. The objective of this study is to optimize the process parameters for the fastest print time possible while minimizing the loss in ultimate strength. Design of experiments (DOE) was employed using a split-plot design with five factors. Analysis of variance (ANOVA) was employed to verify the model significance or otherwise. Once the model was developed, confirmation points were run to validate the model. The model was confirmed since the observations at the optimum were within the prediction interval with a confidence value of 95%. Then, the model was used to assess the ultimate strength and print time of FDM parts with consideration to nozzle diameter, the number of outer shells, extrusion temperature, infill percentage, and infill pattern. Recommendations are discussed in detail in this study to reduce print time without sacrificing significant part strength
A New Method for Evaluation of Mechanical Properties of Glass/Epoxy Composites at Low Temperatures
ΠΠ»Ρ ΡΠ°ΡΡΠ΅ΡΠ° ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΎΠ΄Π½ΠΎΠ½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ° ΠΏΡΠΈ ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
Π²ΠΈΠ΄Π°Ρ
Π½Π°Π³ΡΡΠΆΠ΅Π½ΠΈΡ Π² ΡΡΠ»ΠΎΠ²ΠΈΡΡ
ΠΊΠΎΠΌΠ½Π°ΡΠ½ΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΡ ΠΈ -60Β°C ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½Ρ Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΌΠΎΠ΄Π΅Π»ΠΈ, ΡΡΠΈΡΡΠ²Π°ΡΡΠΈΠ΅ ΠΌΠΈΠΊΡΠΎΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΠ΅ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠ². Π ΠΎΡΠ»ΠΈΡΠΈΠ΅ ΠΎΡ ΡΡΠ°Π½Π΄Π°ΡΡΠ½ΡΡ
ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ², Π±Π°Π·ΠΈΡΡΡΡΠΈΡ
ΡΡ Π½Π° ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°Ρ
ΠΈΡΠΏΡΡΠ°Π½ΠΈΠΉ ΠΎΠ±ΡΠ°Π·ΡΠΎΠ² ΠΈΠ· ΠΎΠ΄Π½ΠΎΠ½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°, Π² Π΄Π°Π½Π½ΠΎΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΠΈΠ·ΠΌΠ΅ΡΡΡΡΡΡ ΠΌΠΈΠΊΡΠΎΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΠ΅ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΡΡΠ΅ΠΊΠ»ΠΎΠ²ΠΎΠ»ΠΎΠΊΠΎΠ½ ΠΈ ΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠΉ ΠΌΠ°ΡΡΠΈΡΡ. Π‘ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠ°Π·Π½ΡΡ
Π°Π½Π°Π»ΠΈΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ Π²ΡΠΏΠΎΠ»Π½Π΅Π½ ΡΠ°ΡΡΠ΅Ρ ΡΠ΅ΡΡΡΠ΅Ρ
ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΠΌΠΎΠ΄ΡΠ»Π΅ΠΉ ΡΠΏΡΡΠ³ΠΎΡΡΠΈ ΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΏΡΠΈ ΠΊΠΎΠΌΠ½Π°ΡΠ½ΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ΅ ΠΈ -60Β°C.Π‘ ΡΠ΅Π»ΡΡ Π²Π΅ΡΠΈΡΠΈΠΊΠ°ΡΠΈΠΈ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠΎΠ² ΡΠ°ΡΡΠ΅ΡΠ° ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½Ρ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ Π½Π°ΠΈΠ»ΡΡΡΠΈΠΉ ΡΠ°ΡΡΠ΅Ρ ΠΌΠΎΠ΄ΡΠ»Π΅ΠΉ ΡΠΏΡΡΠ³ΠΎΡΡΠΈ ΠΎΠ΄Π½ΠΎΠ½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ° ΠΏΡΠΈ ΠΊΠΎΠΌΠ½Π°ΡΠ½ΠΎΠΉ ΠΈ Π½ΠΈΠ·ΠΊΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ°Ρ
ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΠ²Π°Π΅Ρ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΡΠΏΡΡΠ³ΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ. ΠΠΎΠ»ΡΡΠ΅Π½ΠΎ Ρ
ΠΎΡΠΎΡΠ΅Π΅ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΠΈΠ΅ ΠΌΠ΅ΠΆΠ΄Ρ ΡΠ°ΡΡΠ΅ΡΠ½ΡΠΌΠΈ ΠΈ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠΌΠΈ Π΄Π°Π½Π½ΡΠΌΠΈ ΠΏΠΎ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΠΌ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠ°ΠΌ ΡΡΠΎΠ³ΠΎ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° ΠΏΡΠΈ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Π½ΡΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ°Ρ
.Π ΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΎΠΊ ΠΌΡΡΠ½ΠΎΡΡΡ ΠΎΠ΄Π½ΠΎΠ½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ° ΠΏΡΠΈ ΡΡΠ·Π½ΠΈΡ
ΡΠΈΠΏΠ°Ρ
Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ Π² ΡΠΌΠΎΠ²Π°Ρ
ΠΊΡΠΌΠ½Π°ΡΠ½ΠΎΡ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠΈ Ρ -60Β°Π‘ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΡΡΡΡ Π·Π° Π΄ΠΎΠΏΠΎΠΌΠΎΠ³ΠΎΡ Π°Π½Π°Π»ΡΡΠΈΡΠ½ΠΈΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ Π· ΡΡΠ°Ρ
ΡΠ²Π°Π½Π½ΡΠΌ ΠΌΡΠΊΡΠΎΠΌΠ΅Ρ
Π°Π½ΡΡΠ½ΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°. ΠΠ° Π²ΡΠ΄ΠΌΡΠ½Ρ Π²ΡΠ΄ ΡΡΠ°Π½Π΄Π°ΡΡΠ½ΠΈΡ
ΠΌΠ΅ΡΠΎΠ΄ΡΠ², ΡΠΎ Π±Π°Π·ΡΡΡΡΡΡ Π½Π° ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°Ρ
Π²ΠΈΠΏΡΠΎΠ±ΡΠ²Π°Π½Ρ Π·ΡΠ°Π·ΠΊΡΠ² Π· ΠΎΠ΄Π½ΠΎΠ½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°, Π² Π΄Π°Π½ΡΠΉ ΡΠΎΠ±ΠΎΡΡ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΡΡΡΡ Π²ΠΈΠΌΡΡΡΠ²Π°Π½Π½Ρ ΠΌΡΠΊΡΠΎΠΌΠ΅Ρ
Π°Π½ΡΡΠ½ΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΡΠΊΠ»ΠΎΠ²ΠΎΠ»ΠΎΠΊΠΎΠ½ Ρ Π΅ΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΡ ΠΌΠ°ΡΡΠΈΡΡ. ΠΠ° Π΄ΠΎΠΏΠΎΠΌΠΎΠ³ΠΎΡ ΡΡΠ·Π½ΠΈΡ
Π°Π½Π°Π»ΡΡΠΈΡΠ½ΠΈΡ
ΠΌΠΎΠ΄Π΅Π»Π΅ΠΉ Π²ΠΈΠΊΠΎΠ½Π°Π½ΠΎ ΡΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΎΠΊ ΡΠΎΡΠΈΡΡΠΎΡ
ΡΡΠ·Π½ΠΈΡ
ΠΌΠΎΠ΄ΡΠ»Π΅ΠΉ ΠΏΡΡΠΆΠ½ΠΎΡΡΡ Ρ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΠΌΡΡΠ½ΠΎΡΡΡ Π·Π° ΠΊΡΠΌΠ½Π°ΡΠ½ΠΎΡ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠΈ Ρ-60Β°Π‘. ΠΠ· ΠΌΠ΅ΡΠΎΡ Π²Π΅ΡΠΈΡΡΠΊΠ°ΡΡΡ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡΠ² ΡΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΊΡΠ² ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ Π΅ΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½Ρ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½Π½Ρ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΠΎ Π½Π°ΠΉΠΊΡΠ°ΡΠΈΠΉ ΡΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΎΠΊ ΠΌΠΎΠ΄ΡΠ»Π΅ΠΉ ΠΏΡΡΠΆΠ½ΠΎΡΡΡ ΠΎΠ΄Π½ΠΎΠ½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ° Π·Π° ΠΊΡΠΌΠ½Π°ΡΠ½ΠΎΡ Ρ Π½ΠΈΠ·ΡΠΊΠΎΡ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ Π·Π°Π±Π΅Π·ΠΏΠ΅ΡΡΡ Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½Ρ ΠΏΡΡΠΆΠ½ΠΎΡ ΠΌΠΎΠ΄Π΅Π»Ρ. ΠΡΡΠΈΠΌΠ°Π½ΠΎ Ρ
ΠΎΡΠΎΡΡ Π²ΡΠ΄ΠΏΠΎΠ²ΡΠ΄Π½ΡΡΡΡ ΠΌΡΠΆ ΡΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΊΠΎΠ²ΠΈΠΌΠΈ ΠΉ Π΅ΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΈΠΌΠΈ Π΄Π°Π½ΠΈΠΌΠΈ ΡΠΎΠ΄ΠΎ ΠΌΠ΅Ρ
Π°Π½ΡΡΠ½ΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΡΡΠΎΠ³ΠΎ ΠΌΠ°ΡΠ΅ΡΡΠ°Π»Ρ ΠΏΡΠΈ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΡΠ²Π°Π½ΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ°Ρ
Progressive Failure Analysis of Glass/Epoxy Composites at Low Temperatures
ΠΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠ² Π² ΠΊΠΎΡΠΌΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΈ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΡΠ΅Ρ
Π½ΠΈΠΊΠ΅ ΠΎΠ±ΡΡΠ»ΠΎΠ²Π»ΠΈΠ²Π°Π΅Ρ Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΠΎΡΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ Π°ΡΠΌΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
Π²ΠΎΠ»ΠΎΠΊΠ½Π°ΠΌΠΈ ΡΡΠ΅ΠΊΠ»ΠΎΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠ². ΠΠ΄Π½Π°ΠΊΠΎ Π² Π½Π°ΡΡΠΎΡΡΠ΅Π΅ Π²ΡΠ΅ΠΌΡ ΠΎΡΡΡΡΡΡΠ²ΡΡΡ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΡΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΡ
ΠΈ ΡΠ°ΡΡΠ΅ΡΠ½ΡΡ
ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ ΠΏΡΠΎΡΠ΅ΡΡΠ° ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ ΡΡΠ΅ΠΊΠ»ΠΎΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠ³ΠΎ Π»Π°ΠΌΠΈΠ½Π°ΡΠ° (Ρ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΎΡΠΎΠΌ Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΠΉ ΠΈΠ»ΠΈ Π±Π΅Π· ΡΠ°ΠΊΠΎΠ²ΠΎΠ³ΠΎ) Π² ΡΡΠ»ΠΎΠ²ΠΈΡΡ
ΡΠ΅ΡΠΌΠΎΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΡΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π½Π°Π³ΡΡΠΆΠ΅Π½ΠΈΡ ΠΏΡΠΈ Π½ΠΈΠ·ΠΊΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ°Ρ
. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π° ΠΌΠΎΠ΄Π΅Π»Ρ, ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡΠ°Ρ ΡΠ°ΡΡΡΠΈΡΠ°ΡΡ ΠΏΡΠΎΡΠ΅ΡΡ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ Π² ΠΊΠ²Π°Π·ΠΈΠΈΠ·ΠΎΡΡΠΎΠΏΠ½ΡΡ
ΠΏΠ»Π°ΡΡΠΈΠ½Π°Ρ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ° ΠΏΡΠΈ Π½ΠΈΠ·ΠΊΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ°Ρ
. ΠΡΡ
ΠΎΠ΄Π½ΠΎΠ΅ Π·Π½Π°ΡΠ΅Π½ΠΈΠ΅ ΠΏΡΠ΅Π΄Π΅Π»ΡΠ½ΠΎΠΉ Π½Π°Π³ΡΡΠ·ΠΊΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ΅ΡΡΡ Π² ΡΠΏΡΡΠ³ΠΎΠΉ ΠΏΠΎΡΡΠ°Π½ΠΎΠ²ΠΊΠ΅. ΠΠ°Π³ΡΡΠ·ΠΊΠ° ΠΏΠΎΠ²ΡΡΠ°Π΅ΡΡΡ ΠΏΠΎΡΠ°Π³ΠΎΠ²ΠΎ, Π΄Π»Ρ ΠΊΠ°ΠΆΠ΄ΠΎΠ³ΠΎ ΡΡΠΎΠ²Π½Ρ ΡΠ°ΡΡΡΠΈΡΡΠ²Π°ΡΡΡΡ Π½Π°ΠΏΡΡΠΆΠ΅Π½ΠΈΡ ΠΈ ΠΎΡΠ΅Π½ΠΈΠ²Π°Π΅ΡΡΡ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΠ΅ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΠ΅ Ρ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡΠ΅Π³ΠΎ ΠΊΡΠΈΡΠ΅ΡΡ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ. Π‘Π²ΠΎΠΉΡΡΠ²Π° ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° Π² ΡΠ°Π·ΡΡΡΠ΅Π½Π½ΠΎΠΉ ΡΠ°ΡΡΠΈ Π»Π°ΠΌΠΈΠ½Π°ΡΠ° Π²Π°ΡΡΠΈΡΡΡΡ ΡΠΎΠ³Π»Π°ΡΠ½ΠΎ ΡΠΈΠΏΡ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ Π½Π΅Π½ΡΠ»Π΅Π²ΠΎΠ³ΠΎ ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° Π΄Π΅Π³ΡΠ°Π΄Π°ΡΠΈΠΈΠΆΠ΅ΡΡΠΊΠΎΡΡΠΈ. ΠΠ°Π»Π΅Π΅ Π²ΡΠΏΠΎΠ»Π½ΡΠ΅ΡΡΡ ΠΌΠΎΠ΄ΠΈΡΠΈΡΠΈΡΠΎΠ²Π°Π½Π½Π°Ρ ΠΈΡΠ΅ΡΠ°ΡΠΈΡ ΠΡΡΡΠΎΠ½Π°βΠ Π°ΡΡΠΎΠ½Π° Π΄ΠΎ ΠΌΠΎΠΌΠ΅Π½ΡΠ° ΡΡ
ΠΎΠ΄ΠΈΠΌΠΎΡΡΠΈ. Π Π°ΡΡΠ΅Ρ ΠΏΠΎΠ²ΡΠΎΡΡΠ΅ΡΡΡ Π΄Π»Ρ ΠΊΠ°ΠΆΠ΄ΠΎΠ³ΠΎ ΠΏΡΠΈΡΠΎΡΡΠ° Π½Π°Π³ΡΡΠ·ΠΊΠΈ Π²ΠΏΠ»ΠΎΡΡ Π΄ΠΎ ΠΏΠΎΠ»Π½ΠΎΠ³ΠΎ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ Ρ ΠΎΡΠ΅Π½ΠΊΠΎΠΉ ΠΏΡΠ΅Π΄Π΅Π»Π° ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π½ΡΠΉ ΠΌΠ΅ΡΠΎΠ΄ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΠ²Π°Π΅Ρ Ρ
ΠΎΡΠΎΡΠ΅Π΅ ΡΠΎΠ³Π»Π°ΡΠΎΠ²Π°Π½ΠΈΠ΅ ΠΌΠ΅ΠΆΠ΄Ρ ΡΠ°ΡΡΠ΅ΡΠ½ΡΠΌΠΈ ΠΈ ΡΠΊΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΡΠΌΠΈ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌΠΈ ΠΏΡΠΈ ΠΊΠΎΠΌΠ½Π°ΡΠ½ΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ΅ ΠΈ -60Β°Π‘. ΠΡΠ΅Π½ΠΈΠ²Π°Π΅ΡΡΡ Π²Π»ΠΈΡΠ½ΠΈΠ΅ Π½ΠΈΠ·ΠΊΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΡ Π½Π° ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ ΠΏΠ»Π°ΡΡΠΈΠ½ ΠΈΠ· ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°.ΠΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½Ρ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΡΠ² Ρ ΠΊΠΎΡΠΌΡΡΠ½ΡΠΉ Ρ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΡΠΉ ΡΠ΅Ρ
Π½ΡΡΡ Π·ΡΠΌΠΎΠ²Π»ΡΡ Π½Π΅ΠΎΠ±Ρ
ΡΠ΄Π½ΡΡΡΡ Π²ΠΈΠ·Π½Π°ΡΠ΅Π½Π½Ρ ΠΌΠ΅Ρ
Π°Π½ΡΡΠ½ΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ Π°ΡΠΌΠΎΠ²Π°Π½ΠΈΡ
Π²ΠΎΠ»ΠΎΠΊΠ½Π°ΠΌΠΈ ΡΠΊΠ»ΠΎΠ΅ΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΈΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΡΠ². ΠΠ΄Π½Π°ΠΊ Π΄ΠΎ ΡΡΠΎΠ³ΠΎΠ΄Π½Ρ Π²ΡΠ΄ΡΡΡΠ½Ρ Π΄Π°Π½Ρ Π΅ΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΈΡ
Ρ ΡΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΊΠΎΠ²ΠΈΡ
Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½Ρ ΠΏΡΠΎΡΠ΅ΡΡ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ ΡΠΊΠ»ΠΎΠ΅ΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠ³ΠΎ Π»ΠΎΠΌΡΠ½Π°ΡΠ° (ΡΠ· ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΎΡΠΎΠΌ Π½Π°ΠΏΡΡΠΆΠ΅Π½Ρ Π°Π±ΠΎ Π±Π΅Π·) Π² ΡΠΌΠΎΠ²Π°Ρ
ΡΡΠ°ΡΠΈΡΠ½ΠΎΠ³ΠΎ Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ Π·Π° Π½ΠΈΠ·ΡΠΊΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ. ΠΠ°ΠΏΡΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΎ ΠΌΠΎΠ΄Π΅Π»Ρ, ΡΠΎ Π΄ΠΎΠ·Π²ΠΎΠ»ΡΡ ΡΠΎΠ·ΡΠ°Ρ
ΡΠ²Π°ΡΠΈ ΠΏΡΠΎΡΠ΅Ρ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ Π² ΠΊΠ²Π°Π·ΡΡΠ·ΠΎΡΡΠΎΠΏΠ½ΠΈΡ
ΠΏΠ»Π°ΡΡΠΈΠ½Π°Ρ
Π·Π° Π½ΠΈΠ·ΡΠΊΠΈΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ. ΠΠΎΡΠ°ΡΠΊΠΎΠ²Π° Π²Π΅Π»ΠΈΡΠΈΠ½Π° Π³ΡΠ°Π½ΠΈΡΠ½ΠΎΠ³ΠΎ Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ Π²ΠΈΠ·Π½Π°ΡΠ°ΡΡΡΡΡ Ρ ΠΏΡΡΠΆΠ½ΡΠΉ ΠΏΠΎΡΡΠ°Π½ΠΎΠ²ΡΡ. ΠΠ°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ Π·Π±ΡΠ»ΡΡΡΡΡΡΡΡ ΡΡΡΠΏΠ΅Π½Π΅Π²ΠΎ, Π΄Π»Ρ ΠΊΠΎΠΆΠ½ΠΎΠ³ΠΎ ΡΡΠ²Π½Ρ ΡΠΎΠ·ΡΠ°Ρ
ΠΎΠ²ΡΡΡΡΡΡ Π½Π°ΠΏΡΡΠΆΠ΅Π½Π½Ρ ΠΉ ΠΎΡΡΠ½ΡΡΡΡΡΡ ΠΌΠΎΠΆΠ»ΠΈΠ²Π΅ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ Π·Π° Π΄ΠΎΠΏΠΎΠΌΠΎΠ³ΠΎΡ ΠΊΡΠΈΡΠ΅ΡΡΡ ΠΌΡΡΠ½ΠΎΡΡΡ. ΠΠ»Π°ΡΡΠΈΠ²ΠΎΡΡΡ ΠΌΠ°ΡΠ΅ΡΡΠ°Π»Ρ Π² ΡΠ°ΡΡΠΈΠ½Ρ Π»Π°ΠΌΡΠ½Π°ΡΠ°, Π΄Π΅ ΠΌΠ°Π»ΠΎ ΠΌΡΡΡΠ΅ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ, Π²Π°ΡΡΡΡΡΡ Π·Π³ΡΠ΄Π½ΠΎ Π· ΡΠΈΠΏΠΎΠΌ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ Π· Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½ΡΠΌ Π½Π΅Π½ΡΠ»ΡΠΎΠ²ΠΎΠ³ΠΎ ΠΊΠΎΡΡΡΡΡΡΠ½ΡΠ° Π΄Π΅Π³ΡΠ°Π΄Π°ΡΡΡ ΠΆΠΎΡΡΡΠΊΠΎΡΡΡ. ΠΠ°Π»Ρ Π²ΠΈΠΊΠΎΠ½ΡΡΡΡΡΡ ΠΌΠΎΠ΄ΠΈΡΡΠΊΠΎΠ²Π°Π½Π° ΡΡΠ΅ΡΠ°ΡΡΡ ΠΡΡΡΠΎΠ½Π°βΠ Π°ΡΡΠΎΠ½Π° Π΄ΠΎ ΠΌΠΎΠΌΠ΅Π½ΡΡ Π·Π±ΡΠΆΠ½ΠΎΡΡΡ. Π ΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΎΠΊ ΠΏΠΎΠ²ΡΠΎΡΡΡΡΡΡΡ Π΄Π»Ρ ΠΊΠΎΠΆΠ½ΠΎΠ³ΠΎ ΠΏΡΠΈΡΠΎΡΡΡ Π½Π°Π²Π°Π½ΡΠ°ΠΆΠ΅Π½Π½Ρ Π°ΠΆ Π΄ΠΎ ΠΏΠΎΠ²Π½ΠΎΠ³ΠΎ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ Π· ΠΎΡΡΠ½ΠΊΠΎΡ Π³ΡΠ°Π½ΠΈΡΡ ΠΌΡΡΠ½ΠΎΡΡΡ. ΠΠ°ΠΏΡΠΎΠΏΠΎΠ½ΠΎΠ²Π°Π½ΠΈΠΉ ΠΌΠ΅ΡΠΎΠ΄ Π·Π°Π±Π΅Π·ΠΏΠ΅ΡΡΡ Ρ
ΠΎΡΠΎΡΡ Π²ΡΠ΄ΠΏΠΎΠ²ΡΠ΄Π½ΡΡΡΡ ΠΌΡΠΆ ΡΠΎΠ·ΡΠ°Ρ
ΡΠ½ΠΊΠΎΠ²ΠΈΠΌΠΈ ΠΉ Π΅ΠΊΡΠΏΠ΅ΡΠΈΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΈΠΌΠΈ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌΠΈ Π·Π° ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠΈ -60Β°Π‘ ΡΠ° ΠΊΡΠΌΠ½Π°ΡΠ½ΠΎΡ. ΠΡΡΠ½ΡΡΡΡΡΡ Π²ΠΏΠ»ΠΈΠ² Π½ΠΈΠ·ΡΠΊΠΎΡ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠΈ Π½Π° ΠΌΠ΅Ρ
Π°Π½ΡΠ·ΠΌ ΡΡΠΉΠ½ΡΠ²Π°Π½Π½Ρ ΠΏΠ»Π°ΡΡΠΈΠ½ ΡΠ· ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ°
Consensus Middle East and North Africa Registry on Inborn Errors of Immunity
Background: Inborn errors of immunity (IEIs) are a heterogeneous group of genetic defects of immunity, which cause high rates of morbidity and mortality mainly among children due to infectious and non-infectious complications. The IEI burden has been critically underestimated in countries from middle- and low-income regions and the majority of patients with IEI in these regions lack a molecular diagnosis. Methods: We analyzed the clinical, immunologic, and genetic data of IEI patients from 22 countries in the Middle East and North Africa (MENA) region. The data was collected from national registries and diverse databases such as the Asian Pacific Society for Immunodeficiencies (APSID) registry, African Society for Immunodeficiencies (ASID) registry, Jeffrey Modell Foundation (JMF) registry, J Project centers, and International Consortium on Immune Deficiency (ICID) centers. Results: We identified 17,120 patients with IEI, among which females represented 39.4%. Parental consanguinity was present in 60.5% of cases and 27.3% of the patients were from families with a confirmed previous family history of IEI. The median age of patients at the onset of disease was 36Β months and the median delay in diagnosis was 41Β months. The rate of registered IEI patients ranges between 0.02 and 7.58 per 100,000 population, and the lowest rates were in countries with the highest rates of disability-adjusted life years (DALY) and death rates for children. Predominantly antibody deficiencies were the most frequent IEI entities diagnosed in 41.2% of the cohort. Among 5871 patients genetically evaluated, the diagnostic yield was 83% with the majority (65.2%) having autosomal recessive defects. The mortality rate was the highest in patients with non-syndromic combined immunodeficiency (51.7%, median age: 3.5Β years) and particularly in patients with mutations in specific genes associated with this phenotype (RFXANK, RAG1, and IL2RG). Conclusions: This comprehensive registry highlights the importance of a detailed investigation of IEI patients in the MENA region. The high yield of genetic diagnosis of IEI in this region has important implications for prevention, prognosis, treatment, and resource allocation
A RARE CASE OF TUBAL PREGNANCY
<font><font color="#555555"><span style="font-size: 10pt; font-family: Tahoma">The tubal pregnancy is one of the most emergency cases in Ob & Gyn. EP Forms the second etiology of maternal mortality in USA.<br />So the early diagnosis of EP will save the life of mother and reserve her reproductive potential. Many cases of tubal pregnancy ended during the first trimester by intraperitoneal rupture since the oviduct is very narrow.<br />We have hada rare case which the tubal pregnancy continued for six month while the oviduct was completely safe. this case can rise question about the previous tubal pathological theories.</span></font></font>
Tensile, compressive and shear properties of unidirectional glass/epoxy composites subjected to mechanical loading and low temperature services
299-309Composite materials are subjected to low
temperatures in service and this has induced the need for a proper knowledge of
low temperature behavior of composites. Most of the research in this field is
focused on applying different types of loading and laminated configurations.
This paper discusses the experimental study on the tensile, compressive and
in-plane shear behavior of unidirectional (UD) glass fiber reinforced polymeric
composite under static and low temperature loading conditions. Since UD
composite is the basic building block of a composite structure and can be used
to make general laminates. In order to fully characterize UD laminate, several
experimental tests are performed using an environmental test chamber and a
universal testing machine. Thermo-mechanical loads are applied to glass/epoxy
unidirectional laminates at room temperature (25Β°C), -20Β°C and -60Β°C. The
results of the present study indicate that low temperatures have a significant
effect on composite failure mode. It is also found that the strength and
modulus of UD composites both increased with decreasing the temperature in all
cases including tensile, compressive and shear loads. On the other hand, the
results show that strain to failure decreased by decreasing the temperature
Dynamic failure behavior of glass/epoxy composites under low temperature using Charpy impact test method
211-220This paper demonstrates results of an experimental study on
glass/epoxy laminated composites subjected to low velocity impact at energy
levels equal to 10, 15 and 30 J
under variable temperatures in the range of -30Β°C to 23Β°C. The
configuration of specimens is quasi-isotropic. The low temperature and its
influence on the maximum absorbed energy, elastic energy, crack length and
delamination are highlighted. Also, the effects of geometry index
(span-to-depth) and notch orientation are studied. Failure mechanisms of
specimens are examined using microscopic examinations. Results indicate that
impact performance of these composites is affected over the range of
temperature considered. Failure mechanism is changed from matrix cracking at
room temperature to delamination and fiber breakage at low temperatures
Identifying sustainable warehouse management system indicators and proposing new weighting method
The performance of a sustainable warehouse management system is a multidimensional concept based on the triple bottom line approach. It has been a challenge to identify the key performance indicators for a sustainable warehouse management system and to develop a model for evaluating the direct and indirect indicators. In order to overcome this challenge, this paper describes a method to identify and weight indicators that assess sustainability in a sustainable warehouse management system using structural equation modeling. A comprehensive literature review has been conducted and a questionnaire survey involving experts in the field has been undertaken. A list of 33 key performance indicators for a sustainable warehouse management system has been proposed, and this can be used by policymakers to appraise the sustainability performance of a sustainable warehouse management system. The proposed robust model can weight indicators and evaluate the total effect of each indicator in incorporating sustainability in a sustainable warehouse management system. The developed method could also be applied to weighting indicators for other industries
Status of estrogene, progesterone receptors and HER-2/neu expression in invasive breast cancer
Background&Objective: The breast cancer is the most common malignancy in women. The normal and malignant breast tissue are under the regulatory effects of esteroid hormones and growth factors including HER-2/neu. The purpose of this study, is to determine the expression of estrogene receptor (ER) progesterone receptor(PR) and HER-2/neu among Iranian women with invasive breast cancer. Materials&Methods: The study is descriptive and cross-sectional that was performed on 50 samples of patients with invasive breast cancer in Imam-Khomeini Hospital-Sari (2005-06). After preparing the samples four tissue sections from each sample was obtained then H&E and IHC staining were performed. Results: In our study, the patients were between 28-88 yrs, (mean:52/6). ER and PR and HER-2/neu were positive in 80%, 72% and 57.1% of cases, respectively. Concurrent positive ER and PR was 70%, meanwhile 62.9% of these patient were also positive for HER-2/neu. 20% of the cases showed negativity for both ER and PR and of these 83.4% were also negative for HER-2/neu. Conclusion: In our study ER expression by itself is equal to previous studies in textbooks but PR expression, HER-2/neu and concurrent expression of ER&PR are higher in our study. Interestingly HER-2/neu expression is near to what was previously proposed by Iranian Blood Transfusion Organization and Kerman University of Medical science. It seems that racial and geographic factors are contributed for these diffrences