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Indonesia is one of the top three countries in the world for fisher fatalities due to a lack of stability monitoring, poor vessel design, and the fishers’ poor safety culture. Improved safety through technology, in particular stability awareness, has been identified as a key aspect to prevent capsizing and sinking. Despite the low technology uptake by Indonesian fishers, they are known to make extensive use of smart mobile phones as a primary form of communication. These phones are equipped with various sensors, including motion sensors that can be used by different mobile applications. This paper proposes the use of a mobile application to aid Indonesian fishers in assessing the stability of their vessel by using results from a roll decay test or realtime roll motion data monitored when operating at sea. For the pre-departure test, the mobile application uses the onboard gyroscope to record the roll angle time series which can then be used to quantify the roll period. An offline calculation is then carried out to approximate the vessel’s metacentric height. This is then visually presented using a traffic light system to provide the fishermen with a simple indication of whether the vessel is stable or not. Should the boat be unstable, additional guidance is provided to improve the vessel’s stability. The realtime monitoring system alerts the fishers when the thresholds are exceeded, to ensure realtime awareness of increased risk to the stability of the vessel.

Determination of service speed has always become a primary concern when designing a ship. However, a ship designer may not consider its effect on the use of energy and seakeeping performance of the vessel. The current paper discusses the determination of the actual and proper speed of a ro-ro ferry, operated between Tanjung Perak (Surabaya) and Lembar (Lombok), based on resistance estimation and seakeeping performance. The investigation is carried out using commercial software MaxsurfTM and further compared with computational fluid dynamics (CFD) approach to capture the effect of detailed wave drag, which is not quantified by the design software. The discussion and analysis include the determination of optimum speed based on the size of main engine and the seakeeping performance of the ship covering the aspects of heave, pitch, and roll.

The seafaring and fishing industries in Indonesia have been severely affected by the COVID-19 pandemic. There is an urgent need to research the best technical solutions to ensure the safety of seafarers and fishers so that they can keep working safely at sea. It is highly unlikely that the Indonesian fleet will be able to rapidly return to the pre-COVID-19 situation within the next few years. Therefore, long-term solutions are required. This research aims to provide guidance for owners, operators and masters to reconfigure their vessels and operations to ensure a safe working environment to counter the potential spread of the virus, as well as maintaining the integral safety of the vessels. The present paper reports several primary activities, including analysis of existing guidelines, questionnaire survey, computational fluid dynamics, remote monitoring and machine learning. These works are expected to provide indications on virus-hazardous areas for ships, inform guidelines on hygienic and reconfiguring means to counter COVID-19 and potentially the spread of similar viruses, and further establish a long-term monitoring and optimising system for ship safety and performance.

Herb/plant can act as a prebiotic. Red ginger has long known as an anti-inflamation and anti-oxidant. Similarly, moringa leaf is also known as herbal antibiotic. In the recent years, the use of natural ingredients to stimulate immune system and to combat fish disease in aquaculture becoming a favourable choice. The aims of this research was to observe the red ginger and moringa leaf extractin the diet to the performance of catfish infected by Aeromonas hydrophila. Experimental laboratory using a completely randomized design with 6 treatments and 3 replication used in this study. The treatments were mixture of (A) 500 ppm and 0 ppm, (B) 375 ppm and 150 ppm, (C) 250 ppm and 300 ppm, (D) 125 ppm and 450 ppm, (E) 0 ppm and 600 ppm, (F) 0 ppm and 0 ppm mixture of red ginger and moringa leaf extract respectively. One hundred and eighty catfish juvenile were reared in 18 aquarium. They were fed with various concentration of prebiotic mixture for 14 days. They were infected with 1 mL A. hydrophila at 1.2 105cell/cc intramuscularly and observed for 10 days for their survival and immune response. Results showed that addition of red ginger and moringa leaf extract significantly improve the immunity of catfish. The addition of moringa leaf extract at 600 ppm was significantly improved survival rate, phagocytosis activities, leucocyte, lymphocytes count compared to other prebiotic mixtures. Thus, the usage of 600 ppm moringa leaf extract in the diet provided the best performance to catfish.

This paper examines whether simultaneous market orientation and environmental innovation may drive organizations’ environmental sustainability performance, with environmental innovation as a mediation. Market orientation, innovation, and performance: the relationship between the three constructs has been shown in several previous investigations, but not many results have been obtained about how it impacts the environment. We study market orientation relationships as separate variables, namely customer orientation, competitor orientation, and interfunctional coordination. The examination every market orientation component that affects organizational environmental innovation on how to change environmental sustainability performance. The method used to analyze data is modeling the structural equations of cross-sectional survey data with the SMART-PLS software, using 300 manufacture small businesses located in Indonesia. We empirically test and substantiate that not all components of market orientation have a significantly positive effect on environmental sustainability performance, but environmental innovation is an excellent mediator. Our findings show that small businesses can improve their market orientation capabilities and innovate in overcoming the challenges of environmental damage in the future, even with limited resources.

Estimating shaft power of a crew boat is very important to be analysed because it has high-speed operational characteristics along with limited routes. To understand the phenomena, 3 sister crew-boats with operational distance about 40-60 nautical miles every day are investigated. The daily operational time is 8 hours and the configurations are: 4.04% full speed, 13.63% economical speed, 1.81% slow speed, 7.65% snatching, 1.25% manoeuvring, 5.29% idle, and the remaining time is in standby condition. The crew boats are fitted with a monitoring system namely SHIMOS®, in which data is sent to a server in the centre office every 2 minutes. The data consists of time capture, boat position (latitude and longitude), speed, left and right RPM engine, left and right flow-meter data engine, and average of fuel consumption data in everyday operation. Three years of data has been collected for the vessel. The present study proposed characteristics of crew-boat shaft power, which affected by external factors using Artificial Neural Network (ANN) back propagation method and optimisation in 4 hidden layers and 40 neurons with relative error 6.2%. The results demonstrates good agreement with previous popular method that using statistical models.

The Saka calendrical inscriptions recorded the time journey in its own specific way, such as the use of suklapaksa and kresnapaksa, equipped with saptawara, pancawara and sadwara day names. At the next stage, it is addedd with wuku. During the Majapahit era, the time dimensional recording was expanded to include such elements as naksatra, yoga, karaṇa, muhūrta, dewatā, grahacāra, parweśa, mandala, and rāśi. This article traces the journey of usage of these time dimensions and completes it with the sculpture samples in some inscriptions from Majapahit era or after, and proposes it as the archipelago’s ethnoastronomy.

A Raman spectroscopy study on the half-doped single-layer manganite Pr0.5Ca1.5MnO4 has been performed in combination with x-ray diffraction, resistivity, magnetization, and specific heat measurements. The results provide insight into the underlying mechanisms of phenomena that arise from correlations between lattice, charge, orbital, and spin degrees of freedom. The appearance of a new Raman mode at 366 cm(-1), a visible jump in the resistivity, and a doubling of the unit cell signify the onset of charge/orbital ordering at 320 K. This transition is also marked by a sharp peak in the magnetic susceptibility and specific heat, suggesting strong spin-charge coupling. Our structural analysis suggests that the charge disproportionation below 320 K is small. Orbital fluctuations below 320 K are evidenced by the evolution with temperature of the Jahn-Teller Raman mode (situated at 533 cm(-1) at 320 K). A coincidence between the onset of two-dimensional short-range antiferromagnetic order at 215 K and anomalies in both the temperature dependence of the Jahn-Teller mode and the Mn-O bonding pattern in the ab plane indicate that the short-range magnetic order plays a role in stabilizing the orbital fluctuations. Below the Neel temperature of 127 K, the softening of both the 366 cm(-1) mode and an octahedral tilting mode at 214 cm(-1) mark the onset of three-dimensional antiferromagnetic ordering. The estimated spin-phonon coupling constants for these two modes are 2.6 and 6.8 cm(-1), respectively. This study highlights the remarkable coupling of charge, orbital, and spin degrees of freedom to the lattice in single-layer Pr0.5Ca1.5MnO4.

We demonstrate, using a combination of experiment and density functional theory, that orbital ordering drives the formation of a one-dimensional (1D) $S=1/2$ antiferromagnetic spin chain in the 3D rocksalt structure of cesium superoxide (${\mathrm{CsO}}_{2}$). The magnetic superoxide anion (${\mathrm{O}}_{2}^{\ensuremath{-}}$) exhibits degeneracy of its $2p$-derived molecular orbitals, which is lifted by a structural distortion on cooling. A spin chain is then formed by zigzag ordering of the half-filled superoxide orbitals, promoting a superexchange pathway mediated by the ${p}_{z}$ orbitals of ${\mathrm{Cs}}^{+}$ along only one crystal direction. This scenario is analogous to the $3d$-orbital-driven spin chain found in the perovskite ${\mathrm{KCuF}}_{3}$ and is the first example of an inorganic quantum spin system with unpaired $p$ electrons.

Magnetic dioxygen molecules can be used as building blocks of model systems to investigate spin-polarization that arises from unpaired p-electrons, the scientific potential of which is evidenced by phenomena such as spin-polarized transport in graphene. In solid elemental oxygen and all of the known ionic salts comprised of magnetic dioxygen anions and alkali metal cations, the dominant magnetic interactions are antiferromagnetic. We have induced novel ferromagnetic interactions by introducing oxygen deficiency in rubidium superoxide (RbO(2)). The anion vacancies in the resulting phase with composition RbO(1.72) provide greater structural flexibility compared to RbO(2) and facilitate a Jahn-Teller-driven order-disorder transition involving the anion orientations at similar to 230 K, below which their axes become confined to a plane. This reorganization gives rise to short-range ferromagnetic ordering below similar to 50 K. A ferromagnetic cluster-glass state then forms below similar to 20 K, embedded in an antiferromagnetic matrix that orders at similar to 5 K. We attribute this inhomogeneous magnetic order to either subtly different anion geometries within different structural nanodomains or to the presence of clusters in which double exchange takes place between the anions, which are mixed-valence in nature. We thus demonstrate that nonstoichiometry can be employed as a new route to induce ferromagnetism in alkali metal oxides.

We give general arguments that show that the linear magnetoelectric effect in antiferromagnetic materials gives rise to a magnetocapacitance anomaly-a divergence of the dielectric constant at the magnetic ordering temperature T-N that appears in an applied magnetic field. The measurement of magnetodielectric response thus provides a definitive and experimentally accessible method to recognize antiferromagnetic linear magnetoelectric materials, circumventing the experimental difficulties often involved in measuring electric polarization. We confirm this result experimentally using the example of MnTiO3, which we show to exhibit the linear magnetoelectric effect. No dielectric anomaly is observed at T-N in the absence of an applied magnetic field. However, a sharp peak in the dielectric constant appears here when a magnetic field is applied along the c axis, reflecting a linear coupling of the polarization P with the antiferromagnetic order parameter L. In accordance with our theoretical analysis, the dielectric constant close to T-N increases with the square of the magnetic field.

Since one decade ago, a new paradigm of vaccine design is emerging. Instead of attenuated virulent microorganisms or killed virulent microorganisms, effective subunit vaccines were developed using recombinant DNA technology. By using the technology, selected genes of the virulent microorganisms can be cloned, expressed, and evaluated as vaccine components. In this research, hydrophilic domain of S protein (aa 100-164)-encoding gene of hepatitis B surface antigen was cloned for vaccine candidate production. The gene was ligated with pGEX-4T-2 vector and sequenced. Sequences aligment of the amplified fragment with genome of hepatitis B virus indicated that the sequences were identical. A major result achieved from this research was clones carrying S antigens-encoding gene that could be used further for production of recombinant hepatitis B vaccine candidates.

An experimental study on Mn-dopant-induced effects in Zn1−xMnxO was performed for samples with x = 0.02, 0.04, 0.06, and 0.08, which were prepared by solid state reaction at 1200 °C. The result of x-ray diffraction refinement analysis did not turn up evidence of MnxOy cluster inclusion over the entire doping range, while the structural parameter variations indicate a solubility limit of about 6% for Mn2+ and incorporation of Mn ions of higher valency at higher dopant levels. The magnetization data exhibit mostly intrinsic antiferromagnetic instead of ferromagnetic properties, as predicted by more recent theoretical works. The substitutional incorporation of the Mn in ZnO was further confirmed by the associated broad-band photoluminescence spectra. The suggested incorporation of Mn ions of higher valency at higher dopant concentration was also supported by the related x-ray photoemission data, and in agreement with a previous theoretical prediction.