2 research outputs found
ν΄λμ© μ μκΈ°κΈ°μ νμ§λ³΄μ¦ λ¨μ©λ°©μ§μ© μ₯μΉμ λν μ±λ₯ μ ν λͺ¨λΈ κ°λ°
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Όλ¬Έ (μμ¬)-- μμΈλνκ΅ λνμ : κΈ°κ³ν곡곡νλΆ, 2013. 8. μ€λ³λ.μ΅κ·Ό μ€λ§νΈν°μ΄λ νλΈλ¦Ώ PCμ κ°μ ν΄λμ© μ μκΈ°κΈ°κ° λ³΄νΈν λλ©΄μ κ·Έμ λν μμ₯κ·λͺ¨κ° κΎΈμ€ν μ±μ₯νκ³ μλ€. μ΄μ λ°λΌ μ μμ νμ νμ§λ³΄μ¦ μλΉμ€μ λν κ΄μ¬μ΄ λμμ§κ³ μλλ°, μ΄μ κ΄λ ¨νμ¬ νμ§λ³΄μ¦ λ¨μ©μ μν΄ μ€μΉλ μΉ¨μλΌλ²¨μ μ±λ₯μ λν λ
Όλμ΄ νλλκ³ μλ€. μΉ¨μλΌλ²¨μ μ μμ ν μΆμ μ κΈ°κΈ° λ΄λΆμ λΆμ°©λλ©° λ¬Όμ΄λ μ‘체μ λΏμΌλ©΄ λ³μλλ κΈ°λ₯μ κ°μ§κ³ μμΌλ©°, μλΉμκ° μ ν μ¬μ© μ€μ κΈ°κΈ°λ₯Ό λ¬Όμ λΉ λ¨λ Έλμ§ νλ¨ν μ μλ κΈ°μ€μ΄ λκ³ μλ€. λ³μλ μΉ¨μλΌλ²¨μ κ°μ§κ³ μλ μ νμ μλΉμμ κ³Όμ€λ‘ μΈν νμ κ°λ₯μ±μ΄ ν¬λ€κ³ νλ¨λμ΄ μΆν νμ§λ³΄μ¦ μλΉμ€μ μ κ³΅μ΄ λμ§ μλλ€.
νμ§λ§ μ΅κ·ΌκΉμ§ νμ§λ³΄μ¦ μλΉμ€λ₯Ό λ°μ§ λͺ»ν λ€μμ μλΉμμκ²μ μΉ¨μλΌλ²¨μ μ€μλμ λν μ£Όμ₯μ΄ λμμμ΄ μ μλλ©΄μ μ΄μ λν μ§λ¨ μμ‘μΌλ‘ λ¬Έμ κ° νμ°λκ³ μλ€. μ΄λ¬ν λ¬Έμ μ ν΄κ²°μ μν΄μλ λ€μν νκ²½μμ μΉ¨μλΌλ²¨μ μ±λ₯μ 보μ΄λ μ λμ μΈ κΈ°μ€κ³Ό μ¬λ°λ₯Έ μΉ¨μλΌλ²¨μ μ€μΉ λ°©λ²μ λν 곡νμ κ·Όκ±°κ° νμνλ€.
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μνμ ν΅ν΄ μ±λ₯μ ν λͺ¨λΈμ μ μνμ¬ λ€μν νκ²½ λ΄ μΉ¨μλΌλ²¨μ μ±λ₯μ μ λννμλ€. κ°μμλͺ
μνμ κ²°κ³Ό λΆμμλ RGB μμ λͺ¨λΈμ μ΄μ©ν μ΄λ―Έμ§ νλ‘μΈμ± κΈ°λ²μ λμ
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μνμ κ²°κ³Όλ‘λΆν° μΉ¨μλΌλ²¨μ μ±λ₯μ μμΈ‘νλ λͺ¨λΈ ꡬμΆμλ Arrhenius Relationshipμ λμ
νμ¬ μ€μ μ ν μ΄μ© νκ²½μμμ μΉ¨μλΌλ²¨μ μ±λ₯μ μμΈ‘νμλ€. λν μ€μ μ€λ§νΈν°μ μ΄μ©νμ¬ λͺ¨λΈ κ²μ¦ μνμ μνν¨μΌλ‘μ¨ μ μλ μ±λ₯μ ν λͺ¨λΈμ μ ν¨μ±μ λ°νμΌλ©°, μΉ¨μλΌλ²¨μ μ¬λ°λ₯Έ μ€μΉ κΈ°μ€μ λν 곡νμ μ견μ λμΆνμλ€.The market for portable electronics (i.e. smartphones, tablet PCs, laptops) has been expanding gradually and customers expectations for high reliability cause various controversial issues. Industry use of a liquid damage indicator (LDI) as a method for warranty abuse is one of the problems receiving customers attention. As the price for electronic devices has increased, customers have become more concerned about warranty policies of electronic device manufacturers. Some customers have even abused the warranty service and made unfair profit. As a result, electronic device manufacturers have decided not to provide warranty service for damage resulting from the fault of customers, especially as it relates to liquid-damaged products. Electronic device manufacturers have increasingly employed LDIs in products to detect if a device has been damaged by liquid. An LDI is a sticker which consists of multiple layers. The LDI changes in color from white to red when it comes in contact with liquids. When a customer takes his/her device to a service center, the staff will first check the LDIs color in the device and will refuse to provide warranty service for any device with red LDIs.
However, existing LDIs exhibit inconsistencies in characteristics which can lead to improper warranty denials. Many websites and a few broadcast media sources have presented examples of LDIs showing a faulty alarm based on environmental conditions. At least one major electronics manufacturer, Apple Inc., has been sued over the LDIs poor performance and therefore a possibly unreasonable warranty policy. However, no quantified engineering data existed for objective evaluation of the LDIs performance. Therefore, for the benefit of the public and the protection of electronics manufacturers, a need arose to develop a method that quantifies LDI performance.
In this study, a performance degradation model for an LDI has been developed and validated. The model was developed with following three steps1) accelerated life testing of LDIs on two substrates, 2) performance degradation model development based on the test results, and 3) model validation with environmental cyclic test of LDIs attached in iPhone 3 handsets.Chapter 1. Introduction 1
Chapter 2. Review of Warranty Abuse Detection Methods in Electronic Devices 3
Chapter 3. Overview of Accelerated Life Tests 6
3.1 Stress Acceleration 7
3.1.1 Acceleration method 7
3.1.2 Stress applying method 7
3.2 Types of Stress and Related Stress-Life Models 9
3.2.1 Types of Stress and Related Stress-Life Model 9
3.2.2 Humidity for stress acceleration 10
3.2.3 Non-thermal parameters for stress acceleration 11
3.3 Procedures for Accelerated Life Tests 11
3.3.1 Major failure mechanism 11
3.3.2 Condition settings 12
3.3.3 Data analysis 13
Chapter 4. Pre-tests for Accelerated Life Tests of Liquid Damage Indicators 14
4.1 Main Stress Factor 14
4.1.1 High humidity resistive test 14
4.1.2 Temperature cyclic test 15
4.2 Condition Setting 16
4.2.1 Temperature cyclic test under high and low temperature ranges 16
4.2.2 Temperature stabilization test 18
Chapter 5. Accelerated Life Tests of Liquid Damage Indicators 21
5.1 Procedure of the Accelerated Life Tests 21
5.1.1 Steps for the accelerated life tests 21
5.1.2 Quantification of performance degradation 23
Chapter 6. Development of a Performance Degradation Model 30
6.1 Arrhenius Relationship 30
6.2 Performance Degradation Model for LDI 31
Chapter 7. Validation Tests for the Performance Degradation Model 34
Chapter 8. Conclusion and Discussion 36
Bibliography 38
κ΅λ¬Έ μ΄λ‘ 42Maste