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What Is This Thing Called Six Sigma?
Published in Bob Sproull, Theory of Constraints, Lean, and Six Sigma Improvement Methodology, 2019
Although I support these guidelines, remember right now we are only interested in correcting problems that limit throughput in the constraint operation. My advice to you is to simply analyze the defect data, develop a Pareto chart of the defects, prioritizing them based upon which is having the most detrimental effect on the output rate of the constraint operation (or downstream operations) and decide how you are going to attack them. Once you’ve resolved the highest priority defect, move to the next one and so forth. You cannot simultaneously attack all defects and you cannot afford to have your available resources working on problems that aren’t going to give you pay back in the constraint operation. If you want to start a fire with a magnifying glass, you have to be able to focus the rays of the sun in one location. So too with improving the output of the constraint operation. It’s really all about being able to focus.
Optical Instruments for Viewing Applications
Published in Abdul Al-Azzawi, Light and Optics, 2018
In Figure 14.8(a) the object is located at the near point, where it subtends an angle θ at the eye. In Figure 14.8(b), a converging lens is used to form a virtual image that is larger and farther from the eye than the object. The image formation by converging lenses is widely explained in the lenses chapter. A lens used to enlarge an object is called a simple magnifier, or sometimes is called a magnifying glass. In Figure 14.8(b) a magnifier in front of the eye forms an image at the near point, with the angle θ′ subtended at the magnifier. The magnification power of the magnifier is defined by the ratio of the angle θ′ (viewed with the magnifier) to the angle θ (viewed without the magnifier). This ratio is called the angular magnification Ma, as defined by: () Ma=θ′θ
Optical Instruments for Viewing Applications
Published in Abdul Al-Azzawi, Photonics, 2017
In Figure 14.8(a) the object is located at the near point, where it subtends an angle θ at the eye. In Figure 14.8(b), a converging lens is used to form a virtual image that is larger and farther from the eye than the object. The image formation by converging lenses is widely explained in the lenses chapter. A lens used to enlarge an object is called a simple magnifier, or sometimes is called a magnifying glass. In Figure 14.8(b) a magnifier in front of the eye forms an image at the near point, with the angle θ′ subtended at the magnifier. The magnification power of the magnifier is defined by the ratio of the angle θ′ (viewed with the magnifier) to the angle θ (viewed without the magnifier). This ratio is called the angular magnification Ma, as defined by: Ma=θ′θ
Students’ ability to use geometry knowledge in solving problems of geometrical optics
Published in International Journal of Mathematical Education in Science and Technology, 2023
Aneta Gacovska Barandovska, Boce Mitrevski, Lambe Barandovski
The topics from geometrical optics learned in primary and high school are given as follows: 8th-grade geometrical optics material: types of light sources, propagation of light, point and non-point light sources, shadows, the speed of light and Roemer’s method, reflection of light, the law of reflection, plane mirror and image formation, refraction of light (descriptive approach), total internal reflection, spherical mirrors, spectrum of white light, dispersion of light, lenses and image formation, human eye as an optical system, additive, and subtractive colour mixing.3rd class geometrical optics material: nature of light, speed of light, propagation of light (transmission, reflection, and refraction), the law of reflection and law of refraction of light, total internal reflection, rainbow, plane mirror and image formation, spherical mirrors and image formation, lenses and image formation, optical instruments (magnifying glass and microscope).
3D printing process of oxidized nanocellulose and gelatin scaffold
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Xiaodong Xu, Jiping Zhou, Yani Jiang, Qi Zhang, Hongcan Shi, Dongfang Liu
To characterize the scaffold structure, particularly the cell architecture, several parameters need to be measured through different techniques because they influence both the physical and biological reactions of the scaffold. Young’s modulus (E), shear modulus (G), compressive strength and sticky elasticity have often been measured through stress-strain test to characterize the strength and stiffness of the material or the scaffold [17–20]. Porosity level, which is considered to be the key parameter affecting cell proliferation and differentiation most strongly, has often been measured though the volume method. Furthermore, scanning electron microscopy and X-ray computer tomography are widely used to observe the structure of the scaffold in recent studies since the diameters of the micropores can be observed under high magnification magnifying glass [21–23].
Recent progress of organic light-emitting diode microdisplays for augmented reality/virtual reality applications
Published in Journal of Information Display, 2022
Due to their intrinsic small size, OLED microdisplays can be applied to head-mounted or glass-type AR/VR devices. In head-mounted devices for VR applications, large and high-resolution displays are preferred to improve the FoV and the immersiveness. However, a display size of over 1 inch is difficult to achieve using the conventional CMOS technology with a stepper. Fortunately, the large display size mitigates the design rules up to a few micrometers, enabling the application of the TFT process on the glass substrates with advanced technology. To apply the TFT process, the pixel circuit should be simplified due to the small pixel size. As shown in Figure 6(a), Keum et al. proposed an OLED pixel circuit that consisted of three TFTs (3T) and two capacitors (2C) using the simultaneous emission driving method with a low crosstalk error of less than ±1 least significant bit (LSB) [42]. Using the proposed pixel structure, they demonstrated the 5.87-inch, 1,000 ppi, and 5,120 × 2,880-resolution low-temperature polycrystalline silicon (LTPS)-based AMOLED display panel with a magnifying glass lens for VR applications. Yu et al. also introduced a simple pixel circuit of 3T-1C for high-resolution displays [43]. Different pixel circuits for the p-type metal–oxide-semiconductor (PMOS) and the n-type metal–oxide-semiconductor (NMOS) were developed to consider both the functions and the process capacity. By developing the pixel circuits, TFT processes, and driving schemes, they demonstrated both the 3.23-inch, 1,000 ppi, 2,160 × 2,400-resolution, and 90 fps PMOS display panel and the 2.2-inch, 1,000 ppi, 1,080 × 2,400-resolution, and 120 fps NMOS display panel. Cheng et al. developed the circuitry for a high-resolution AMOLED panel that included a pixel circuit to compensate for the threshold voltage (VTH) variation and the voltage drop, and a gate driver on an array that generated S and E waveforms [44]. To reduce the screen-door effect, the high-resolution OLED patterning process was also developed, which resulted in a high aperture ratio of 17% with a pixel size of 11.4 µm, as shown in Figure 6(b). By integrating the frontplane and backplane technologies, they demonstrated the 2.17-inch, 2,228 ppi AMOLED panel for near-eye applications.