Sistem Pakar Untuk Budidaya Tambak Udang Putih

Tambak udang putih merupakan sebuah ekosistem buatan kompleks yang membutuhkan bantuan manusia untuk mempertahankan keseimbangan elemen-elemen pembentuknya. Permasalahan di dalamnya disebabkan oleh proses ekologis baik secara biologi, kimia, maupun fisika yang saling terkait. Sehingga untuk menghasilkan solusi optimal perlu diperhitungkan bagaimana keterhubungan antar elemen. Pengetahuan mengenai hubungan elemen-elemen tersebut umumnya dikuasai oleh pakar, tetapi tidak seluruh tambak mampu menyediakan pakar dalam budidayanya. Pengembangan sistem pakar dalam penelitian ini ditujukan untuk menjawab kebutuhan pakar di tambak udang menggunakan teknik klasifikasi. Pengetahuan pakar direpresentasikan dalam decision table dengan penggunaan multi atribut. Hasil eksperimen menunjukkan bahwa sistem mampu menghasilkan solusi dari berbagai variasi masalah yang mungkin terjadi di tambak seperti pakar dan fleksibel untuk dimodifikasi. White shrimp embankment is a complex artificial ecosystem that requires human intervention to maintain the balance of its constituent elements. The problems inside are caused by ecological processes therein, either biology, chemistry, and physics that are interlinked so as to produce the optimal solution needs to be taken into account how the connection between elements. Knowledge about the relationships among these elements is generally dominated by experts, but not all embankments are able to provide experts in the cultivation. Development of expert systems in this study aimed to answer the needs of experts in shrimp embankments using the classification technique. Expert knowledge is represented in a decision table with the use of multi attributes. The experimental results show that the system is capable of generating solutions from a variety of problems that may occur in embankments such as expert and versatile to be modified

Pelatihan Double Leg Bound 10 Repetisi 5 Set Meningkatkan Daya Ledak Otot Tungkai Siswa Putra Kelas VIII D SMP PGRI 5 Denpasar Tahun Pelajaran 2015/2016

Pelatihan olahraga merupakan salah satu upaya meningkatkan kondisi kesehatan fisik, disiplin dan sportivitas. Kemampuan yang perlu ditingkatkan dalam olahraga salah satunya adalah daya ledak otot tungkai. Peningkatan daya ledak otot tungkai dapat terjadi dengan melakukan latihan double leg bound. Double leg bound adalah latihan yang dilakukan dengan cara meloncat kedepan dengan 2 tungkai diangkat sampai setinggi dada. Penelitian ini bertujuan untuk mengetahui apakah pelatihan double leg bound dapat meningkatkan daya ledak otot tungkai siswa putra kelas VIII D SMP PGRI 5 Denpasar tahun pelajaran 2015/2016. Penelitian ini menggunakan rancangan experimental randomized pretestand post-test groups design. Populasi diambil dari keseluruhan siswa putra kelas VIII D SMP PGRI 5 Denpasar tahun pelajaran 2015/2016 yang berjumlah 62 orang siswa yang dibagi menjadi kelompok perlakuan dan kelompok kontrol. Hasil penelitian didapatkan rata-rata tes awal daya ledak otot tungkai pada kelompok perlakuan yaitu, 32,660 dan rata-rata tes akhir yaitu 39,087. Sedangkan pada kelompok kontrol rata-rata tes awal yaitu 32,927 dan rata-rata tes akhir yaitu 38,193. Bersadarkan uji t-test independent didapat bahwa beda rerata hasil pre test antara kelompok perlakuan dengan kelompok kontrol sebesar 0,267 dengan hasil p lebih besar dari 0,05 (p > 0.05) yang menunjukkan bahwa ada perbedaan yang bermakna dari hasil pre test antara kelompok perlakuan dengan kelompok kontrol, sedangkan beda rerata hasil post test antara pelatihan double leg bound pada kelompok perlakuan dengan pelatihan alternate leg bound pada kelompok kontrol sebesar 0,894 dengan hasil p lebih besar dari 0,05 (p > 0.05) yang menunjukkan bahwa tidak ada perbedaan yang bermakna dari hasil post test antara kelompok perlakuan dengan kelompok kontrol. Berdasarkan penelitian diatas disarankan agar latihan double leg bound dan alternate leg bound sebagai salah satu latihan untuk meningkatkan daya ledah otot tungkai

Diverse perceptions on eco-certification for shrimp aquaculture in Indonesia

Shrimp is a major aquaculture species in Indonesia. Despite the Indonesian government’s effort to reinforce sustainability practices using a national eco-certification scheme, the uptake of stakeholders has been slow so far. This study analyzed diverse perceptions of the national eco-certification of shrimp aquaculture among stakeholders across the value chain in Indonesia. Using Q-methodology, 49 statements were selected, and they covered seven themes: conceptual understanding, priorities, motivation for eco-certification, market access, impacts of eco-certification, obstacles in Indonesia, and stakeholder involvement. Thirty respondents across the supply chain of whiteleg shrimp sorted these statements according to their level of agreement. Based on their support or opposition to eco-certification, responses were categorized into five perspectives: (1) supporter for the certification by principle, (2) market-oriented supporter, (3) collaborative supporter, (4) ambivalent self-sufficient, and (5) antagonistic business-oriented. Several reasons for stakeholder’s slow acceptance were identified. These include a limited understanding of sustainability concepts in eco-certification, uncertainty for the potential positive effects of eco-certification in terms of market access, the recognition of other priorities such as improving farm-infrastructures, and a lack of stakeholders’ participation in communication forums. The findings of this study can facilitate the process of consensus-building on eco-certification among farmers, scientists, the government, non-governmental organizations, and other stakeholders to support a viable pathway for policy development to achieve sustainable shrimp aquaculture. Ultimately, this study provides new insights on how a country in the Global South perceives eco-certification differently from the Global North.</jats:p

Anatomy of phreatic eruptions

This study investigates phreatic eruptions at two similar volcanoes, Kawah Ijen (Indonesia) and White Island (New Zealand). By carefully processing broadband seismic signals, we reveal seismic signatures and characteristics of these eruptions. At both volcanoes, the phreatic eruptions are initiated by a very-long-period (VLP) seismic event located at shallow depths between 700 and 900 m below the crater region, and may be triggered by excitation of gas trapped behind a ductile magma carapace. The shallow hydrothermal systems respond in different ways. At Kawah Ijen, the stress change induced by VLPs directly triggers an eigenoscillation of the hyperacidic lake. This so-called seiche is characterized by long-lasting, long-period oscillations with frequencies governed by the dimensions of the crater lake. A progressive lateral rupture of a seal below the crater lake and/or fluids migrating toward the surface is seismically recorded ∼ 15 min later as high-frequency bursts superimposed to tilt signals. At White Island, the hydrothermal system later (∼ 25 min) responds by radiating harmonic tremor at a fixed location that could be generated through eddy-shedding. These seismic signals shed light on several aspects of phreatic eruptions, their generation and timeline. They are mostly recorded at periods longer than tens of seconds further emphasizing the need to deploy broadband seismic equipment close to active volcanic activity

High-density production of the rotifer <i>Brachionus plicatilis</i> in a recirculation system: consideration of water quality, zootechnical and nutritional aspects

Rotifers were reared on the artificial diet culture Selco® in batch and recirculation conditions at different water exchange rates. The different rearing conditions resulted in considerable changes in water quality, which in their turn affected rotifer growth and food consumption. At a daily water exchange rate of 100%, no positive effect was obtained in rotifer growth compared to the batch rearing system, but the rotifer culture period could be prolonged by 1 week. By increasing the daily water exchange rate from 100 to 300% the maximum rotifer density could be significantly (P -1. At the highest recirculation rate (daily water exchange of 500%) the highest rotifer production (2800 individuals per milliliter in 11 days) was obtained after adjustment of the feeding scheme. This adjustment was necessary to compensate for food losses in the recirculation system. The use of a modified culture Selco (CSH) could further improve the performance of the rotifers. Using this experimental diet, a rotifer density of 8000 individuals per milliliter could be obtained in 8 days without rinsing and restocking during the production period. When the rotifer populations were kept below their maximal density by daily harvests the culture period could be extended to more than 1 month. During this period the cultures were not subjected to any water exchange or restocking except the replacement of the water to compensate for the daily harvested rotifers (±20% of the standing population). In general terms it can be stated that the use of a recirculation system has proved to reduce labour and maintenance cost while ensuring stable physico-chemical rearing conditions resulting in more reliable and healthy rotifer cultures

Technical and economical feasibility of a rotifer recirculation system

A feasibility study was performed on the use of a recirculation system for the mass culturing of rotifers at industrial level. Rotifer culture systems with a culture volume of 750 l were operated at three different stocking densities (3000, 5000 and 7000 individuals ml-1) in a completely closed recirculation system. At all operating rotifer densities, a reliable production of 2.2 billion rotifers could be obtained on a daily basis during 3 weeks. Excellent water quality was maintained by the use of protein skimmers, the use of ozone and a submerged biofilter. The microbial counts remained stable during the whole culture period (106 CFU ml-1 on marine agar and 104 CFU ml-1 on TCBS after 15 and 23 days, respectively). No difference in HUFA and protein content were obtained between rotifers harvested from the recirculation system or from a conventional batch culture system. Compared to a commercial batch culture system, the use of a recirculation system can contribute to a 43% saving on the capital investment and the annual operation cost. By using this system, capital investment cost is considerably reduced by 46%. Savings are also made on labour cost (65%) and feed cost (21%) during a 1-year production. In general terms, it can be stated that by using a simple recirculation system, a cost-effective technology and a reliable rotifer culture can be obtained

Technical and economical feasibility of a rotifer recirculation system

A feasibility study was performed on the use of a recirculation system for the mass culturing of rotifers at industrial level. Rotifer culture systems with a culture volume of 750 l were operated at three different stocking densities (3000, 5000 and 7000 individuals ml-1) in a completely closed recirculation system. At all operating rotifer densities, a reliable production of 2.2 billion rotifers could be obtained on a daily basis during 3 weeks. Excellent water quality was maintained by the use of protein skimmers, the use of ozone and a submerged biofilter. The microbial counts remained stable during the whole culture period (106 CFU ml-1 on marine agar and 104 CFU ml-1 on TCBS after 15 and 23 days, respectively). No difference in HUFA and protein content were obtained between rotifers harvested from the recirculation system or from a conventional batch culture system. Compared to a commercial batch culture system, the use of a recirculation system can contribute to a 43% saving on the capital investment and the annual operation cost. By using this system, capital investment cost is considerably reduced by 46%. Savings are also made on labour cost (65%) and feed cost (21%) during a 1-year production. In general terms, it can be stated that by using a simple recirculation system, a cost-effective technology and a reliable rotifer culture can be obtained

The use of ozone in a high density recirculation system for rotifers

The use of ozone in the effluent treatment of a closed recirculation system for rotifers resulted in a significant improvement of rotifer production and water quality. Compared to a control treatment, the rotifer culture exposed to ozone did not only support a higher rotifer biomass (16000 vs. 8000 rotifers ml-1), it also allowed a prolongation of the culture period for 4 days. Compared to a control treatment, the ammonium levels were reduced by 67%, nitrite levels by 85% and nitrate levels by 67%. The supplementation of ozone did not affect pH and dissolved oxygen levels. Besides the positive effect of ozone to the nitrification process, a better removal of suspended solids was noticed as well. This resulted in a decreased turbidity and a reduction of the number of particles in the culture water. The use of ozone also reduced the number of bacteria in the culture water. In general terms, it can be stated that supplementation of ozone in a closed recirculation system for rotifers considerably improves water quality, ensures stable and longer rotifer culture periods and controls bacterial proliferation