Identifikasi Kawasan Penangkapan Induk Udang Windu (Penaeus Monodon) pada Perairan Pesisir Kabupaten Aceh Jaya

Tujuan penelitian ini adalah untuk menetapkan kawasan penangkapan induk udang windu (Penaeus monodon) dan kondisi lingkungan perairannya ditinjau dari aspek fisika kimia perairan pada kawasan perairan kabupaten Aceh Jaya. Penelitian ini menggunakan pendekatan survey dan teknologi system informasi geografis. Kawasan penangkapan induk udang di Kabupaten Aceh Jaya pada umumnya terdapat pada titik ordinat: (1) H 950 34\u27 bujur timur dan 040 38\u27 lintang utara, (2) H 950 33\u27 bujur timur dan 040 39\u27 lintang utara, (3) H 950 34\u27 bujur timur dan 040 40\u27 lintang utara, (4) H 950 34\u27 bujur timur dan 040 33\u27 lintang utara. Parameter fisika kimia perairan yang diukur pada kawasan penangkapan induk udang menunjukkan kondisi yang sangat sesuai bagi sistem kehidupan udang.The aims of this study was to establish the broodstock catchment areas of tiger prawn (Penaeus monodon) and the condition of the waters which was surrounding their habitat in terms of environmental aspects of physical chemical water parameter in the coastal waters of Aceh Jaya region. This study used survey approach and geographic information system technology as methodelogy. The catching areas of broodstock in Aceh Jaya region commonly found on the ordinate point: (1) H 950 34\u27 east longitude and 040 38\u27 north, (2) H 950 33\u27 east and 040 39\u27 north, (3) H 950 34\u27 east and 040 40\u27 north, (4) H 950 34\u27 east and 040 33\u27 north. Physical and chemical parameters of water measured at catchment areas showed that the water parameters in the prawn habitat were very suitable for supporting of tiger prawn living

Finite Element Thermal Analysis of Conformal Cooling Channels in Injection Moulding

The process cycle time in injection moulding process depends greatly on the cooling time of the plastic part, which is facilitated by the cooling channels in the injection mould. Effective cooling channel design in the mould is important because it not only affects cycle time but also the part quality. Traditional cooling channels are normally made of straight drilled holes in the mould, which have limitations in geometric complexity as well as cooling fluid mobility within the injectio n mould. Over the years, conformal cooling techniques are being introduced as effective alternative to conventional cooling. The main objective of this study is to determine an optimum design for conformal cooling channel of an injection moulded plastic part using finite element analysis and thermal heat transfer analysis. The part cooling time is optimized by conformal cooling channels in the mould using the ANSYS thermal a nalysis software. Analysis of virtual models showed that those with conformal cooling channels predicted a significant reduction of cycle time with expected improvement in part quality

Effect of Pre-sowing Treatments on Germination and Initial Growth of Terminalia citrina: A Medicinal Tree Species in Bangladesh

Terminalia citrina (Gaertn.) Roxb. ex. Fleming (local name-Hatiyal) is an important medicinal tree species naturally grown in Sal and hill forests of Bangladesh. An experiment was conducted at the Institute of Forestry and Environmental Sciences, University of Chittagong, Bangladesh, to find out the effects of pre-sowing treatments on germination and vigor seedling production capability. Seeds were treated with six pre-sowing treatments, e.g. T0-seeds without any treatment (Control), T1-seeds soaking in normal water for 24 hours and sown in polybags (24º C), T2-seeds soaking in normal water for 48 hours and sown in polybags (24º C), T3-fruits sown in seedbed, T4-seeds soaking in hot water for 1 minute and sown in propagator house (80º C), and T5-seeds sown in propagator house. Highest germination percentage (95.83%), germination energy (37.5%), and germination value (1.0506) were found in T5 treatment (seed sown in propagator house) and significantly (p<0.05) different from other treatments. Collar diameter and leaf number were recorded after three and four months of seed germination. After 3 months of the last germination, maximum shoot height (46.6 cm) was revealed in T2 (seeds immersed in normal water for 48 hours and sown in polybags) treatment. Collar diameter (6.02 mm) and leaf number (12.6) were recorded highest in T2 treatment. The lowest diameter (4.23 mm) and leaf number (5.8) were found in T4 treatment (seeds soaking in hot water for 1 minute and sown in propagator house). Finally, seeds sown in the propagator house (sand media) revealed comparatively better germination behaviour but low growth performance. Seeds treated with normal water for 48 hours treatment revealed appropriate for vigour and quality seedlings production for T. citrina

Multi-agent deep reinforcement learning with centralized training and decentralized execution for transportation infrastructure management

We present a multi-agent Deep Reinforcement Learning (DRL) framework for managing large transportation infrastructure systems over their life-cycle. Life-cycle management of such engineering systems is a computationally intensive task, requiring appropriate sequential inspection and maintenance decisions able to reduce long-term risks and costs, while dealing with different uncertainties and constraints that lie in high-dimensional spaces. To date, static age- or condition-based maintenance methods and risk-based or periodic inspection plans have mostly addressed this class of optimization problems. However, optimality, scalability, and uncertainty limitations are often manifested under such approaches. The optimization problem in this work is cast in the framework of constrained Partially Observable Markov Decision Processes (POMDPs), which provides a comprehensive mathematical basis for stochastic sequential decision settings with observation uncertainties, risk considerations, and limited resources. To address significantly large state and action spaces, a Deep Decentralized Multi-agent Actor-Critic (DDMAC) DRL method with Centralized Training and Decentralized Execution (CTDE), termed as DDMAC-CTDE is developed. The performance strengths of the DDMAC-CTDE method are demonstrated in a generally representative and realistic example application of an existing transportation network in Virginia, USA. The network includes several bridge and pavement components with nonstationary degradation, agency-imposed constraints, and traffic delay and risk considerations. Compared to traditional management policies for transportation networks, the proposed DDMAC-CTDE method vastly outperforms its counterparts. Overall, the proposed algorithmic framework provides near optimal solutions for transportation infrastructure management under real-world constraints and complexities

Analisa Perubahan Fase Pada Sistem Pengkondisian Udara Ruangan Type Split 1 Pk

Pendingin ruang yang menggunakan sistem kompresi uap dengan menggunakan alat penukar kalor sehingga terjadi Perubahan panas dan tekanan yang berada pada tekanan rendah dan tekanan tinggi yang stabil, dalam sistem ini menggunakan bahan pendingin (refrigerant) yang bersirkulasi menyerap panas dan melepas panas, serta terjadi Perubahan dari tekanan rendah ke tekanan tinggi. Sirkulasi tersebut berulang secara terus-menerus dan jumlah refrigerant yang digunakan tetap dan hanya bentuk dari refrigerant saja yang berubah. Subjek penelitian ini adalah mesin pendingin jenis splite dengan kapasitas 1 PK yang banyak di gunakan di gedung kecil atau ruangan. Sedangkan untuk objek penelitian ini terdapat pada system pendingin air conditioner (AC) yang mempunyai karakteristik yang unik, panas dari engine serta kondisi-kondisi lainnya yang mempengaruhi design dan masalah pada sistem air conditioner (AC). Dari hasil penelitian dapat disimpulkan bahwa semakin tinggi putaran kompresor maka COP akan menurun, meningkatnya putaran kompresor menyebabkan temperature dan tekanan refrigerant yang keluar kompresor akan semakin meningkat, sehingga kerja kompresi yang dilakukan juga semakin besar. Hal ini berkebalikan dengan temperatur dan tekanan refrigerant yang masuk ke evaporator. Temperature dan tekanan refrigerant yang masuk evaporator akan semakin rendah dengan meningkat putaran kompresor, hal ini menyebabkan efek refrigrasi yang dihasilkan semakin rendah.Kata Kunci : Pengkondisian udara, kompresor, evaporato

FORMULATION AND IMMUNOSTIMULANT STABILITY POLYSACCHARIDE SYRUP OF FRACTION NONI (MORINDA CITRIFOLIA L.) FRUITS

Objective: The study aimed to formulate standardized polysaccharide fraction of Noni (SPFN) fruit into syrup preparations to fulfill the acceptability requirement of National Agency of Drugs and Food Control [Badan Pengawas Obat dan Makanan Republik of Indonesia (BPOM RI)] so that it can be used in the community as an immunostimulant. Methods: The optimization of the formula A and B were done using Simplex Lattice Design (SLD) method and its stability tested under extreme temperature change effect using thaw cycling method by evaluating the physical properties, microbial contamination and immunostimulant activity. MTT method was used to determine the immunostimulant activity of syrup against lymphocyte proliferation in vitro. Results: Based on the results of stability tests of formula A using pH (4.45), viscosity (81.03 mPas), taste (good taste), pouring power (2.31 s), amount of bacteria (68 colonies/ml), total yeast and mold (269 colonies/ml) parameters and fulfilled the acceptability requirement of BPOM RI. Formula A could maintain better stability than formula B. Formula A syrup used for immunostimulant activity testing that could increase lymphocyte proliferation at a concentration of 13.33 to 106.64 μg/μl and it’s stable under the influence of extreme temperature changes. Conclusion: Formula A could be used to produce SPFN syrup, which has stable physical properties and immunostimulant activity beside no microbial contamination that fulfill requirements of BPOM RI

Metal hierarchical patterning by direct nanoimprint lithography

Three-dimensional hierarchical patterning of metals is of paramount importance in diverse fields involving photonics, controlling surface wettability and wearable electronics. Conventionally, this type of structuring is tedious and usually involves layer-by-layer lithographic patterning. Here, we describe a simple process of direct nanoimprint lithography using palladium benzylthiolate, a versatile metal-organic ink, which not only leads to the formation of hierarchical patterns but also is amenable to layer-by-layer stacking of the metal over large areas. The key to achieving such multi-faceted patterning is hysteretic melting of ink, enabling its shaping. It undergoes transformation to metallic palladium under gentle thermal conditions without affecting the integrity of the hierarchical patterns on micro- as well as nanoscale. A metallic rice leaf structure showing anisotropic wetting behavior and woodpile-like structures were thus fabricated. Furthermore, this method is extendable for transferring imprinted structures to a flexible substrate to make them robust enough to sustain numerous bending cycles

Hawking radiation of scalar particles from accelerating and rotating black holes

Hawking radiation of uncharged and charged scalars from accelerating and rotating black holes is studied. We calculate the tunneling probabilities of these particles from the rotation and acceleration horizons of these black holes. Using the tunneling method we recover the correct Hawking temperature as well

Circadian Organization in Hemimetabolous Insects

The circadian system of hemimetabolous insects is reviewed in respect to the locus of the circadian clock and multioscillatory organization. Because of relatively easy access to the nervous system, the neuronal organization of the clock system in hemimetabolous insects has been studied, yielding identification of the compound eye as the major photoreceptor for entrainment and the optic lobe for the circadian clock locus. The clock site within the optic lobe is inconsistent among reported species; in cockroaches the lobula was previously thought to be a most likely clock locus but accessory medulla is recently stressed to be a clock center, while more distal part of the optic lobe including the lamina and the outer medulla area for the cricket. Identification of the clock cells needs further critical studies. Although each optic lobe clock seems functionally identical, in respect to photic entrainment and generation of the rhythm, the bilaterally paired clocks form a functional unit. They interact to produce a stable time structure within individual insects by exchanging photic and temporal information through neural pathways, in which serotonin and pigment-dispersing factor (PDF) are involved as chemical messengers. The mutual interaction also plays an important role in seasonal adaptation of the rhythm

Hawking temperature of rotating charged black strings from tunneling

Thermal radiations from spherically symmetric black holes have been studied from the point of view of quantum tunneling. In this paper we extend this approach to study radiation of fermions from charged and rotating black strings. Using WKB approximation and Hamilton-Jacobi method we work out the tunneling probabilities of incoming and outgoing fermions and find the correct Hawking temperature for these objects. We show that in appropriate limits the results reduce to those for the uncharged and non-rotating black strings