Playing Ping Pong With Light: Directional Emission of White Light

Over the last decades, light-emitting diodes (LED) have replaced common light bulbs in almost every application, from flashlights in smartphones to automotive headlights. Illuminating nightly streets requires LEDs to emit a light spectrum that is perceived as pure white by the human eye. The power associated with such a white light spectrum is not only distributed over the contributing wavelengths but also over the angles of vision. For many applications, the usable light rays are required to exit the LED in forward direction, namely under small angles to the perpendicular. In this work, we demonstrate that a specifically designed multi-layer thin film on top of a white LED increases the power of pure white light emitted in forward direction. Therefore, the deduced multi-objective optimization problem is reformulated via a real-valued physics-guided objective function that represents the hierarchical structure of our engineering problem. Variants of Bayesian optimization are employed to maximize this non-deterministic objective function based on ray tracing simulations. Eventually, the investigation of optical properties of suitable multi-layer thin films allowed to identify the mechanism behind the increased directionality of white light: angle and wavelength selective filtering causes the multi-layer thin film to play ping pong with rays of light.

Photoluminescence studies on LiNa5(PO4)2:Dy3+, Sm3+ phosphor

This paper describes the preparation, structure and photoluminescence properties of a new class LiNa5(PO4)2:Dy3+, Sm3+-phosphor. Crystalline nature confirmed by X-ray diffraction. The phases obtained are in good agreement with the standard phase. Excitation dependence and concentration effect on luminescence features are investigated. Color purity and optical bandgap are also estimated for the LiNa5(PO4)2:Dy3+, Sm3+ phosphors. The result shows LiNa5(PO4)2:Dy3+, Sm3+-phosphor excited by 374 nm nUV light produces pure white light than others. Admixing of 4f configurations and energy transfer between dopants are identified while varying the concentration of Sm3+. The CIE coordinates for LiNa5(PO4)2:0.05Dy3+, 0.05Sm3+ (x = 0.309, y = 0.332) are positioned well in white light region and very close to pure white light. The present study on LiNa5(PO4)2:Dy3+, Sm3+-phosphor suggests that it is useful for the fabrication of white light emitting diodes.

Glory In White: Analogi Arsitektur Hotel Majapahit Dalam Penciptaan Busana Dengan Classic Elegant Style

Majapahit Hotel Surabaya is one of the Dutch colonial legacy and also a historical place forSurabayan people. The pure white nuance and the mixed of Art Nouveau and Art Decoarchitecture style of the hotel makes the hotel has its own uniqueness. Through theanalogy theory, the shapes that can describe the Majapahit Hotel is its architecture andinterior such as crystal lamp, symmetrical, flag terrace as one of the iconic construction ofthe hotel, geometric, arc line and clasic elegant. Those shapes become the style in thisfashion artwork which processed and can realize the Ready to Wear, Ready to WearDeluxe, and Haute Cotour the fashion artworks, which has been considered based on theexisted element and tenet. The creative creation process uses Tjok Instri Ratna CoraSudharsana design method named "FRANGIPANI, The Secret Steps of Art Fashion" whichconsist of ten steps of design fashion planning process.

Pure White Cell Aplasia an exceptional condition in the inmunological conundrum of thymomas: Responses to inmunosupresion and Literature Review.

Thymomas are tumours frequently associated with autoinmune manifestations or immunodeficiencies like Good syndrome. In rare cases, pure white cells aplasia (PWCA) has been described in association with thymomas. PWCA is characterized by agranulocytosis of autoinmune background primary refractory to granulocyte colony-stimulating factor (G-CSF). It is necessary to use inmunosupressor drugs.

Violence/Accommodation Binary in Chesnutt’s The Marrow of Tradition

The present paper examines the divergent attitudes of black characters toward racism in Charles W. Chesnutt’s The Marrow of Traditions (1901). Chesnutt wrote his novel to reflect his opinions on how African Americans should act to improve their situation. To situate the study within the historical and cultural context of Marrow, Black intellectuals’ views, namely Washington and Du Bois, about the complicated problem of ‘color’ were explored. To analyze the contrasting views and actions of Chesnutt’s black characters, the paper uses the lens of postcolonial theory. Although Marrow is not set within a colonial context, postcolonial theoretical frameworks can be used as models to re-read this novel because they deal with intersections of races, classes, cultures, and the oppressor/ oppressed relationship. The paper concludes that Chesnutt has entertained the possibility of a hybrid or third race— as referred to within postcolonial framework—that may succeed where both races (pure white and black) have failed.

Violence/Accommodation Binary in Chesnutt’s The Marrow of Tradition

The present paper examines the divergent attitudes of black characters toward racism in Charles W. Chesnutt’s The Marrow of Traditions (1901). Chesnutt wrote his novel to reflect his opinions on how African Americans should act to improve their situation. To situate the study within the historical and cultural context of Marrow, Black intellectuals’ views, namely Washington and Du Bois, about the complicated problem of ‘color’ were explored. To analyze the contrasting views and actions of Chesnutt’s black characters, the paper uses the lens of postcolonial theory. Although Marrow is not set within a colonial context, postcolonial theoretical frameworks can be used as models to re-read this novel because they deal with intersections of races, classes, cultures, and the oppressor/ oppressed relationship. The paper concludes that Chesnutt has entertained the possibility of a hybrid or third race— as referred to within postcolonial framework—that may succeed where both races (pure white and black) have failed.