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Borate glasses with composition 50B2O3 – (25-x) Bi2O3 – 25ZnO – xTiO2 where x = 0, 1, 2, 3, 4 (mol%) were succesfully fabricated using a convensional melt-quenching technique aimed at tailoring glass suitable for a low loss optical fiber fundament. For this purpose, glasses were characterized for their density, refractive index, reflectance, UV-Vis absorption and FTIR spectra. Density measurement was carried out by applying Archimedes principle. Refractive index was measured using Brewster’s angle method. UV-Vis spectrum was recorded within the range of 200-1100 nm and FTIR measurement was measured at IR range. Combining the spectra data recorded both from UV-Vis–NIR and FTIR, the theoretical minimum loss of the glass was obtained. In addition, the band gap energy of the present glasses was also calculated. From these data, it can be derived many other glass properties such as Oxygen Packing Density (OPD), ionic radius, and polaron radius.

Er3+-doped tellurite glasses with chemical compositions (in mol%): 55TeO2-35ZnO-(5+x)PbO-2Bi2O3-(2-x)Na2O-Er2O3 with x = 0; 0.5; 1.0; 1.5 and 2.0) were synthesized and explored their physical and optical properties. Density and refractive index were measured at room temperature and other physical properties such as ionic packing ratio, field strength, polaron radius, internuclear distance and molar refraction were derived. It was found that Na2O substitution by PbO causes both refractive index and glass density increase.

Due to the colloidal silica has many applications such as coating, a catalyst precursor, a nano-size filler, investment casting, semiconductor wafer polishing, and an inorganic binder, it still attracting to be studied. The colloidal silica layer has been coated on a glass substrate using the spray-coating process. Two kinds of colloidal silica were prepared, i.e., the colloidal silica formed by mixing of nano-silica from Balai Besar Keramik (BKK) and the silane hexamethyldisilazane (HMDS), and the colloidal silica polishing Mastermet (0.06 mm) commercial as a comparison. The HMDS percent was varied at 10, 20, and 30 vol.%. The contact angle measurement obtained the hydrophobic properties of the samples, and a UV-Vis spectrophotometer measured the transmittance samples. A water contact angle of 94.9° is achieved at 10% HMDS. For all samples, the transmittance of the before and after coated glass substrate can reach an average of 89% to 90%. From this study, it is concluded that the BBK nano-silica has met the commercial requirements that are the hydrophobic property in the contact angle and the transmittance.

Borotellurite glasses with composition (in mol%): 57B2O3–20TeO2–15Bi2O3–3TiO2–(4-x)Na2O–1Tm2O3-xHo2O3 (where x = 0, 0.5, 1.0, 1.5, 2.0, and 2.5) have been fabricated and characterized aims at studying their density, molar volume and refractive index. Glasses were fabricated by melt quenching method. Density measurements were carried at room temperature using picnometer while their refractive indices were determined by applying Brewster angle method. It is observed that both density and molar volume tend to increase with increasing Ho3+ ions concentration. The density, molar volume as well as refractive index of the reported glass increases from 4.72 to 4.91 g/cm3, 31.80 – 32.18 cm3/mol, 1.4906 to 1.7253, respectively, with increasing holmium oxide (Ho2O3) concentration. Other properties characterized the glasses were also derived, including oxygen packing density, field strength and polaron radius.

The subsidized housing construction program is spread over two locations with two types of soil layers in South Kalimantan. Because of the difference in the composition and characteristics of the subsoil, the housing construction requires the standardization of design of sub/lower structure of the buildings namely for the deep foundations and shallow foundations which are used as typical subsidized housing foundations in South Kalimantan. This is necessary to ensure that the mass development of the subsidized housing construction meets the safety, time and cost requirements. The standardization of the structure of the lower building using a type of friction support with 4 m long galam wood piles for corner types and 4 section require 4 and 6 galam wood bars. The standardization of the structure of the lower structure on hard soil using a mountain stone foundation with a foundation width of 0.7 m and a foundation height of 0.7 m requires a foundation area of 1.40 - 3.50 square meter.

Physics, an adaptive subject in SMK, is the basis and prerequisite for productive and applicable material, so it needs to be emphasized on problem solving approaches. This study aimed to determine the influence of learning methods based on the problem solving ability on learning outcomes. The intended learning outcomes are cognitive learning outcomes and the learning method used is project based learning. The type of research was quasi-experiment. The population in this study were the 10th grade students of SMK Negeri 5 Surakarta in the 2018/2019 academic year which consisted of 7 majors with 22 classes. The sample of this study were 2 classes from the Mechanical Engineering department, each of which amounted to 35 students. The instrument used in this study consist of 20 multiple choice questions and 5 essay question of the Physics problem solving abilities. Data were analysed using normality test, homogeneity test and hypothesis testing with analysis of variance techniques (ANOVA). Based on the results of the study it was found that the influence of the interaction between learning method and problem solving ability on cognitive learning outcomes showed sig 0.043 ≤ 0.05. It can thus be concluded that there was an influence of the interaction of the learning model with the problem solving ability with cognitive learning outcomes. Therefore project based learning methods can be used as an alternative for teachers in carrying out their learning to create an active learning atmosphere and enhance students’ ability to understand physics problems.

The development of smart-mat as a pressure mapping sensor has received great interest. These sensors have been used for variety of human needs, from medical to smart-house. The main objective of this research is to point out the feasibility and effectivity of mapping fiber sensor subjected to a load given to a certain area to the pressure distribution on the mat surface. The proposed pressure distribution fiber sensor was made by sandwiching partially scratched polymer optical fiber to form a web. Five strands of partially scratched fiber were inserted sandwiched horizontally in a rubber mat and the other six strands were sandwiched vertically. As the mat is loaded, optical fiber sandwiched underneath the load is bent resulting in light attenuation. Analyzing the attenuation light from both sides using matrix method, a contour area representing pressure distribution can be constructive.

− Brewster's angle method is one that commonly used for measuring high index material. This method enables one to measure unlimited range of refractive index. Due to complicated setup of measurement, measurement is commonly carried manually. This paper presents an automatic instrument for measuring Brewster's angle designed using microcontroller unit (MCU) Arduino. Calibration was made by comparing what was measured by this method with that measured using ABBE Refractometer. It was found that both method showed resembling results. The designed instrument is used to measure the value of the refractive index of the Soda-lime planar waveguide, PMMA glass, and Silica glass. From the measurement, it is known that the refractive index value of the three materials are 1.522, 1.463, and 2.055 respectively.

Characterization of soda-lime has been done with aluminum doping on soda-lime glass using an electric-field-assisted solid-state ion exchange method (EFASSiE) to produce an aluminum coating on the glass. EFASSIE is an ion-exchange method that enables the doping of glass surfaces with aluminum ions. The variations used in ion exchange are temperature and electric fields. Variations of temperature start from 400°C until 500°C, increased temperature will cause the ions inside the glass to vibrate and forming a gap, allowed aluminum ions to penetrate into the glass structure. Variations of electric field start from 300-500 V/mm. Electric field that been exposed to the soda lime glass will accelerate the penetration process of the aluminum ion and pushes the smallest ion out of the glass. The results of the soda-lime glass characterization test shows that the greater the value of temperature and electric field used, refractive index of the soda lime after the ion exchange will increase. Otherwise, glass transmittance after ion exchange process has a relatively small compared to the glass before the process. Soda-lime glass Microstructure after the ion exchange process are known from SEM-EDX test, the result proved that alumunium ion penetrate into the soda-lime glass.

This study aims to: 1) obtain the appropriate product of physics Worksheet based on POE, 2) determine the students' performance using POE-based Worksheet to improve the scientific process skill. This research is Research and Development (R & D). The development conducted by referring to the 4-D model (Define, Design, Develop and Disseminate). The subject of this study is the students of SMA Muhammadiyah Imogiri Yogyakarta. The total number of students is 42, 10 students belong to the small group test, 32 students belong to field test. The instruments of the research a questionnaire, test (post-test), and the distribution of student responses on the Worksheet. The results of this study were 1) the development results of physics POE-based Worksheet was feasible by the experts validation based on the content, language, presentation, and good validity graphic; 2) the percentage of learners' success in implementing the skills of the scientific process in the formulating hypotheses (83.1%), choose tools and materials (83.1%), writing experimental data (68.8%), analysing data (72.1%), interpreting data (77.1%) and make conclusions (91.4%). Based on the percentage of students achievement, the result on pre-test 36.5% (not good) and post-test 72.0% (quite good), the results able to be calculated the improvement of students' achievement competencies using N -Gain technique 0.6 which included in the middle category. Based on this result, the developed Worksheet had a decent usage.

Bending in the optical fiber can result in a loss of optical fiber. Bending causes the output light intensity smaller than the intensity of the light source. Bending can be utilized to a sensor based on optical fiber. This paper presents to know the correlation between the optical fiber sensor utilizing bending effect with rubber coil to a circular and an elliptical shape.The principle of this sensor is a detecting change in the output voltage through an optical fiber. The output voltage then converted to transmittance with the program of a computer. The optical fiber is divided into two arms, that is one reference arm and one modulate arm. Fiber bending sensor was made by coiling optical fiber in modulating arm. The displacement loaded to the optical fiber coil in a rubber thread, so that occur of bending. Rubber threaded used to have a 1.0 cm diameter for the circular shape, and 1.1 cm mayor axis and 0.9 cm minor axis for the elliptical shape. Tests are taken from variations in a number of turns, that are 1, 2, 3, and 4 turns and displacement load from 0.0–10.0 mm.The results can be concluded that the loss is greater with the more number of turns. The larger of displacement load has also resulted in the greater loss. The ratio of loss generated to both of the rubber shapes is visible. The circular shape shows that the loss is a very small firstly. But, after the cross section coil turned into an elliptical shape with a minor axis, the loss increased significantly. While for the elliptical shape shows that the loss increased significantly from the first displacement loaded.

Fiber optic is a light waveguides media that are cylindrical. Optical fiber has certain properties when it transmits light so it can be developed to be a sensing device or sensor. Evanescent wave phenomena appear when there are total internal reflections from many modes in an optical fiber. In this research, the Biochemical Fiber Sensor (BFS) using polishing cladding and some of the core fiber will be fabricated. BFS is used to interact with a biochemical compound. The principle of BFS is based on evanescent absorption which absorbs the typical spectrum of a biochemical compound. By measuring the spectrum from the light output in the BFS, evanescent absorption spectra can be analyzed an optical fiber. In this study, the biochemical compounds that used are lindane that is one of the Persistent Organic Pollutants (POPs). The result showed that there is a change from BFS spectra when it was exposed by POPs compound with various concentration. That change showed that there is evanescent absorption in BFS. Concentration of POPs compound is proportional with evanescent absorption of the POPs compound.

Tellurite glasses with compositions of 55TeO2 - (41- x) ZnO-2Bi2O3-2Na2O-xPbO where x = 1.0, 1.5, 2.0, and 2.5% mole (Pb:TZBN glasses) were prepared by melting the mixture at 900°C and quenched rapidly. IR spectra were recorded in the range 400 cm-1 and 4000 cm-1. Analyses were carried out to study the effect of PbO incorporation into the glasses to the shift the main absorption vibrational spectra. The results were then analysed in term of coordination number of Pb as well as the change in mass reduction.

Theoretical and experimental study of light propagation in acrylic triangle waveguides has been studied theoretically and experimentally aimed to obtain a light cone which can tunnel and bring the light to a certain place. Numerical aperture of light cones which have a length of 7 cm but different cross-section area have been measured using he-Ne laser (λ=632 nm) and the results were compared to those obtained theoretically and no significant different was observed.

Research of optical fiber-based heart rate detection sensor has been conducted using the reflection configurationon the thorax motion modified. Optical fiber used in this research was Plastic Optical Fiber (POF) with a diameter of 0.5. Optical fiber system is made with two pieces of fiber, the first fiber is to serve as a transmitter transmitting light from the source to the reflector membrane, the second fiber serves as a receiver. One of the endsfrom the two fibersis pressed and positioned perpendicular of reflector membrane which is placed on the surface of the chest. The sensor works on the principle of intensity changes captured by the receiver fiber when the reflector membrane gets the vibe from the heart. The light source used is in the form of Light Emitting Diode (LED) and Light Dependent Resistor (LDR) as a light sensor. Variations are performed on the reflector membrane diameter. The light intensity received by the detector increases along with the increasing width of the reflector membrane diameter. The results show that this sensor can detect the harmonic peak at a frequency of 1.5 Hz; 7.5 Hz; 10.5 Hz; and 22.5 Hz in a healthy human heart with an average value of Beat Per Minute (BPM) by 78 times, a prototype sensor that is made can work and function properly.

Optical fiber sandwiched pad designed as a pressure mapping sensor has been configured and characterized. Optical fiber sensor was aligned to form a web-like configuration (x- y matrix). Several fibers were positioned to form lines parallel to y-axis while others are in parallel to x-axis. When a mass with a particular surface contour was loaded on the fiber pad, we have shown the dependence of the magnitude of light attenuation on the mass surface contour. Combining these light attenuation results we have successfully constructed a three dimensional contours showing the pressure distribution given by the mass to the fiber pad.

This paper presents the design of a simple and cheap landslide early warning system which mainly consists of a displacement fibre sensor, mechanical displacement converter, and Short Messaging Service (SMS) gateway equipped with a siren. Displacement fibre optic sensors were made by wrapping a polymer optical fibre (POF) around a holey elastic cylinder connected to a mechanical displacement converter that converts a real land displacement in centimetres order of magnitude into millimetres order that fibre optic sensor can detect. From the experimental results we suggest an optical fibre sensor that has ability to monitor land displacement in the range of 40 cm, sensitivity of (5.9 ± 0.2) dB/cm and linearity 99.5% as well as the way of improving sensor performance to meet the real need. A whole system has been tested making use of a slider attached to the mechanical displacement converter. Once a nonzero continuous displacement for 5 seconds or a downward land displacement of 10.0 cm occurs, the system will activate the siren and spread an alert via SMS automatically.