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This paper demonstrates an optical waveguide based- refractive index (RI) sensor using the temperature compensation method. The optical waveguide was formed using a polymethylmethacrylate sheet as the cladding material and unsaturated polyester resin as the core material. The sensor design consists of two input waveguide branches, a sensing area and an output branch. Two light emitting diodes with wavelength of 530 nm and 660 nm were used as light sources. In this work, temperature compensation was done by dual-wavelength technique in which RI and temperature sensitivities were measured at two different wavelengths at 530 nm and 660 nm. Based on the RI and temperature sensitivities, temperature compensation was implemented. Experimental findings indicated that the average relative error of the uncompensated measurement using the light source of 530 nm and 660 nm were 0.4372% and 0.2749%, respectively. Meanwhile, the average error of the temperature compensation method was 0.0344%. Hence, the temperature compensation method provides measurement error up to 92% lower compared to the uncompensated method. As such, the proposed dual-wavelength compensation method could effectively improve the RI measurement accuracy.

Gunungkidul is one of the areas in Indonesia vulnerable to climate change because most of its population depends on the agricultural sector. Some of the agricultural land in this region is dryland with low food crop productivity. This condition can cause household food insecurity problems. Thus, it is necessary to conduct research that aims to describe the food insecurity of poor households in said area. It is equally important to analyze the factors influencing food insecurity of these households. The sample in this study was 75 heads of poor households, and the data was taken in multistages. Descriptive analysis was utilized to describe the profile and food insecurity of the sample. Factors affecting food insecurity were analyzed using multiple linear regression models. The study discovered that their houses had bamboo walls, earth floors, and tile roofs. They mostly received Non-Cash Food Assistance from the government, and only a few received Family Hope Program. All of them had Health Social Security Administering Agency as the health insurance, but not all used the health center as the health facility. They had meals three times per day and consumed meat once a week. The food menu they consumed consisted of rice, vegetables, and side dishes, which were still far from nutritional quality standards. There is no difference in food insecurity of poor households in the hilly areas. Factors influencing food insecurity are income and the number of family members.

Fish is a perishable commodity. Producers can process fish into salted fish to make it more durable, but producers still add harmful food additives to increase the product’s shelf life. The government prohibits the use of formalin as a food additive. This study aimed to identify salted fish traders’ knowledge of formalin abuse and obtain a strategy to minimize formalin abuse in salted fish. The research method was carried out by giving questionnaires, interviews and using the Strategic Assumption Surfacing and Testing (SAST) method. The results showed that the seller’s knowledge was still low regarding the salted fish products sold, food additives, food product preservation, the lack of socialization about food safety, and the characteristics of formalin products. The chosen strategy is based on the level of importance and the level of certainty to minimize the misuse of formalin, namely socialization to sellers and buyers regarding formalin, the dangers and how to use it and the manufacture of portable detection kits/tools that are easy to use and accurate results.

Cilok and siomay are popular snacks for primary to high school students. However, there have been many findings on the addition of harmful additives in these snacks. The aim of this study was identify borax on cilok and siomay qualitatively and quantitatively. The research was conducted using a survey method with a purposive sample. A total of 6 samples of cilok and 8 samples of siomay were obtained from merchants in various schools in Subang district. The detection of borax was carried out by qualitative tests (turmeric paper test, AgNO3 solution test, decay test), quantitative test (titration), texture analysis and color analysis. Based on turmeric paper and AgNO3 solution test, all samples showed positive results. Based on decay test, the cilok and siomay samples could only be stored at room temperature (28°C) for 24 hours. Titration analysis showed that the range of borax content in cilok 0.0907 to 0.5393 % and in siomay from 0.2906 to 1.0550 %. Based on the texture and color analysis, it was found that there was a change in the texture and color of the sample during storage.

Radiation of thoracic computed tomography (CT) involves the breast although it is not considered an organ of interest. According to the International Commission on Radiological Protection (ICRP) No. 103, the breast is an organ with a high level of sensitivity when interacting with x-rays, increasing the potential risk of breast cancer. Therefore, the radiation dose must be optimized while maintaining image quality. The dose optimization can be accomplished using a radiation shield. This study aims to determine the effect of silicone rubber (SR)-lead (Pb) in various thicknesses as an alternative protective material limiting dose and preserving the image quality of the breast in thoracic CT. SR-Pb was made from SR and Pb by a simple method. The SR-Pb had thicknesses of 3, 6, 9, and 12 mm. The breast dose was measured using a CT dose profiler on the surface of the breast phantom. The CT number and the noise level of the resulting image were determined quantitatively. The dose without the radiation shield was 5.4 mGy. The doses measured using shielding with thicknesses of 3, 6, 9, and 12 mm were 5.2, 4.5, 4.3, and 3.3 mGy, respectively. Radiation shielding with a thickness of 12 mm reduced breast surface dose by up to 38%. The CT numbers and noise levels for the left and right breast phantom images were almost the same as those ​​without radiation shields indicating there were only slight artifacts in the image. Therefore, SR-Pb is considered a good shielding material which can be pplied in a clinical setting by placing it directly on the breast surface for dose optimization.

Gamma-ray irradiation is a type of ionizing radiation that can be used to improve the physiological quality of Melaleuca leucadendron L. (gelam) seeds. The focus of the research was to observe the influence of gamma-ray exposed on the vigor of new, and stored seeds of M. leucadendron. Viability testing was carried out. The analyzed of statistic were variance analyzed by analysis using one factor with thirteen treatments (0; 2.5, 5.0, 7.5, 10, 15, 20, 30, 60, 120, 240, 480, 960 Gy) and four replication. A T-test was conducted to decide the effect of the seed storage period on seed viability for all doses of gamma-ray exposure treatment. The new M. leucadendron seeds irradiated up to 960 Gy did not reduce the number of sprouts. However, the seed storage vigor decreased in almost all irradiated doses after two months of storage, except at a dose of 2.5 Gy. The conclusion of this research shows that low-dose irradiation treatment can increase the vigor of the M. leucadendron seeds that have been stored, and it will contribute to the effort to maintain seed viability for conservation purposes.

Strawberry plantlets of the ‘Earlibrite’ variety were irradiated with gamma rays to induce genetic variability for resistance to abiotic stress. This study aimed to identify the DNA polymorphism of ‘Earlibrite’ strawberry mutants using ISSR markers. For this purpose, a population of M1V0 strawberry plants was gamma-irradiated at 20 Gy. In addition, the irradiated plantlets were subcultured onto MS medium enriched with 0.13 M of 1-NAA and 2 M of 6-BAP. The genetic variation of the mutant was molecularly analyzed using the ISSR marker. Analysis was performed on M1V0 mutant plantlets. The results showed that 93.36% of 192 scoreable bands produced by the ISSR markers were polymorphic. An average of PIC values was 0.48 per primer with a range of 0.40 (ISSR_56) to 0.50 (ISSR_22, ISSR_55, ISSR_58, ISSR_60, ISSR_61, ISSR_62 and ISSR_L10). The primer MI ranged from 2.38 (ISSR_62) to 4.85 (ISSR_21). The genetic variation of mutant individuals ranged from 2.74% to 87.04% according to the Jaccard similarity index. Cluster analysis using ISSR markers grouped the ‘Earlibrite’ strawberry mutant genotypes into five distinct groups. It is concluded that 20 Gy gamma-ray induced mutation produces strawberry mutants and that ISSR was a valuable marker for mutant identification.

Social forestry (SF) as a community involvement program in forest areas needs to be frequently evaluated, particularly on policy aspects considering the dynamics of program implementation. Policy issues related to SF program have not been well identified. As a result, the implementation of SF policies may not achieve the target and recurrently lead to new problems. This research aims to develop the best scenario to support the achievement of SF target but is limited to SF areas adjacent to oil palm plantations. The actor-based modelling was developed using Netlogo 6.2 analytical tool. The results showed that the implementation of SF program should include the economic welfare improvement of local communities as a main consideration. The best scenario to achieve SF target is providing full access for local communities to manage forest areas and developing a mechanism to market the commodities by considering domestic wood consumption. The model simulation indicates that this management approach would be able to maintain forest cover as well as increase the community’s income. Therefore, information on wood consumption level needs to be promoted as an investment opportunity in the forestry sector, which has not been well considered previously in SF program. This strategy can be used to increase the participation of local communities in SF program by providing sufficient economic benefit as well as improving the inclusion of local communities in sustainable forest management.

Object recognition with visual computer techniques is a process necessary to detect different objects in a three-dimensional image to get precise results. Color extraction process Red Green Blue (RGB), Red, Green, Blue (HSV) and other color spaces can produce high accuracy and minimize the number of parameters to speed the computing process. In this study the diagnosis of pneumonia was based on a CT scan of the lungs in the color image segmentation process. The removal of color features is done by using the HSV color segmentation method to classify the pneumonia in CT scans, which makes it possible to detect an image segmenting object as a blob. The color sample generates a value that is the reference point for the filter range during the segmentation process, based on the test results. In this process, it is clear how many objects are found as a color-based pneumonia diagnosis by changing the HSV and RGB thresholds.

This article discusses the demographic development of Bandung City from 1907-1996 which was recorded in the works of “Kuncen Bandung” Haryoto Kunto. Haryoto Kunto explored the history of Bandung from old books and arranged in such a way to get a general description of Bandung from time to time. His works use very loose language, almost the same as the colloquial language used in daily conversation. However, his works have important information regarding Bandung’s demographic change, especially in terms of the emergence of immigrants. This study uses a qualitative content analysis method to describe and analyze in detail the description of the demographic dynamics of Bandung in 1907-1996 in Haryoto Kunto’s books, such as Wajah Bandoeng Tempo Doeloe (1984), Semerbak Bunga di Bandung Raya (1986), and Ramadhan di Priangan (1996). Haryoto Kunto describes the history of the city of Bandung in a very interesting way of telling stories using the perspective of city history and the approach of planalogy. Factors that accelerate population development in the city of Bandung are the policy of relocating the capital city of Bandung, relocating the Priangan residency capital, infrastructure development, urbanization, and plantation development. The development of other city infrastructure has added to the heterogeneity of the population of Bandung City. The immigrants in the city of Bandung can be seen from the naming of places and roads, such as Babakan Bogor, Babakan Surabaya, Kampung Jawa, Jalan Naripan (Betawi), Asep Berlian (Palembang), Alketiri Alley, and Aljabri Gang (Arabic), and Chinatown (Ethnic Chinese).

CFD is a numerical approach used to solve fluid problems. In the CFD simulation process, the meshing stage is crucial to produce high accuracy. Meshing is a process where the geometric space of an object is broken down into many nodes to translate the physical components that occur while representing the object’s physical shape. The research objective was to analyze the characteristics of the mesh technique in the Finite Volume Method (FVM) using the RANS (Reynolds - Averaged Navier - Stokes) equation. The numerical simulation approach used three mesh techniques, namely overset mesh, morphing mesh, and moving mesh. The k-ε turbulent model and VOF (Volume of Fluid) were used to model the water and air phases. The mesh technique approach in CFD simulation showed a pattern under experimental testing. This research showed the difference in value to the experimental results, namely by using the moving mesh method, the difference in resistance difference was 8% at high-speed conditions, the difference in trim value at overset mesh was 11%, and the difference in heave value with the moving mesh method was 14% at low speed. The conclusion reported that overset mesh had better than other mesh methods.

The acting on the planing hull is the most complex hydrodynamics simulation. Therefore, an analysis was done to evaluate drag, lift force, and seakeeping in two degrees of freedom (2-DOF) which is heave and trim. It was fundamental aspects of the overall high-speed vessel. This article focused on the hydrodynamic performance of a complete interceptor configuration that could control the motion behavior of deep-V planing hull in calm water conditions. The benchmark study was undertaken by comparing numerical results with experimental study by Park at al. Models with and without interceptors had been analyzed by numerical simulation performed using Reynold Averaged Navier Stokes (RANS) to describe turbulence model with k epsilon based on computational fluid dynamic (CFD). In this study, the interceptor proper applies at a speed of less than Froude number 0.87. Interceptor reduce by 21% drag at Froude number 0.87 and also reduce by 16% trim and 6% heave at Froude number 0.58. Nevertheless, applied interceptor in high Froude number such as more than Froude number 1.16 caused interceptor lose effectiveness due to producing a decisive moment which made negative trim (bow-down) and increase total drag.