62 research outputs found
Penentuan Daya Tampung Beban Cemaran Fecal Coliform Akibat Kondisi Sanitasi Menggunakan Program Qual2e (Studi Kasus Kali Semarang, Jawa Tengah)
Semarang river is located in Central Semarang City which has length 8,25 Km and the large of the watershed or catchment area is 4,430 Km2. With a density of settlements and high population, lack of sanitation infrastructure, rob sometimes happened and land subsidence which is occurred makes Semarang River area is susceptible in health risks.Degradation of water quality occurs due to the contamination of bacterium category of Coliform because of high population, bad of sewage system, lavatory fabrication, septic tank, and infiltration wells which is not eligible both in quality and layout based on pollutant source. Knowing the level of the contamination in Semarang River is needed by identified the load capacity Fecal Coliform contamination by using software QUAL2E.The result of its simulation based on the minimum capacity of Fecal Coliform compared by quality standard of PP No. 82 year 2001 that Semarang River is not comply the requirements of the quality standards of class I Fecal Coliform is > 1.23 E +13 cell/day , class II is> 1.23 E +14 cell/day, class III is > 2,46 E +14 cell/day and IV is > 2.46 E +14 cell/day. Simulation based on the maximum capacity of Fecal Coliform compared by quality standard of PP No. 82 year 2001 that Semarang River is not comply the requirements of the quality standards of class I Fecal Coliform is > 7,70 E +13 cell/day, class II is > 7.70 E +14 cell/day, class III is > 1.54 E +15 cell/day and class IV is > 1.54 E +15 cell/day. The domestic contamination is the largest source of pollution in Semarang River area. It is because the lack of good sanitation in Semarang River area. There are so many things that cause the bad sanitary condition in Semarang River area, such as there's no waste treatment and there are so many septic tank which are not working property
Studi Penurunan Besi (Fe) Dan Mangan (Mn) Dalam Air Tanah Dengan Menggunakan Clay Filter
The use of groundwater as a source of fresh water to the people would become a problem when it contains of Fe and Mn. This happens because in the ground water there is no directly contact with the air outside and the weathering of rocks, so that Fe and Mn in the ground water is still soluble. Meanwhile the amount of Fe and Mn in the ground is never the same in every location. This case could be some impacts to people\u27s kidney health. In this study, content of Fe and Mn in the ground water will be reduced by using Clay filter media. This study uses 3 wells water samples character with different level of Fe and Mn in sample A is 0.001 mg / l Fe, 0.16 mg / l Mn, sample is B 0.019 mg / l Fe, 0.05 mg / l Mn, and sample C is 3,242 mg / l Fe, 0.27 mg / l Mn. The height level of water influence to the Clay filter becomes the consideration in this study, they are 50 cm, 100 cm and 150 cm. Clay Filter is operated for 12 hours continuously with taking the reuslt of filtration sampling per 2 hours. Based on the research, this study finds the operating time to decrease the concentration of Fe and Mn with Clay Filter optimally from the three height levels in all kinds of different water samples and its categorization has reached 100% at the fourth hours
Formulation and solution of a two-stage capacitated facility location problem with multilevel capacities
In this paper, the multi-product facility location problem in a two-stage supply chain is investigated. In this problem, the locations of depots (distribution centres) need to be determined along with their corresponding capacities. Moreover, the product flows from the plants to depots and onto customers must also be optimised. Here, plants have a production limit whereas potential depots have several possible capacity levels to choose from, which are defined as multilevel capacities. Plants must serve customer demands via depots. Two integer linear programming (ILP) models are introduced to solve the problem in order to minimise the fixed costs of opening depots and transportation costs. In the first model, the depot capacity is based on the maximum number of each product that can be stored whereas in the second one, the capacity is determined by the size (volume) of the depot. For large problems, the models are very difficult to solve using an exact method. Therefore, a matheuristic approach based on an aggregation approach and an exact method (ILP) is proposed in order to solve such problems. The methods are assessed using randomly generated data sets and existing data sets taken from the literature. The solutions obtained from the computational study confirm the effectiveness of the proposed matheuristic approach which outperforms the exact method. In addition, a case study arising from the wind energy sector in the UK is presented
Penerapan Sistim Pakar Untuk Pengembangan Strategi Pengamanan Wilayah Perbatasan Laut Indonesia
Perbatasan Negara yang meliputi wilayah daratan dan perairan merupakan manifestasi utama kedaulatanbangsa yang memiliki nilai strategis dalam mendukung keberhasilan pembangunan Nasional. Ditinjau dari letakgeografis, Negara Kesatuan Republik Indonesia (NKRI) berbatasan laut langsung dengan 10 negara tetanggayaitu: Australia, Malaysia, Philipina, Singapura, Thailand, Timor Leste, Papua New Guinea, Vietnam, India,dan Palau, kondisi ini membuat NKRI rentan terjadi pelanggaran wilayah perbatasan laut. Berdasarkan dataFAO tahun 2009, kerugian NKRI tiap tahunnya akibat illegal fishing adalah ± 30 Triliun Rupiah, illegal loggingadalah ± 6.48 Triliun Rupiah, untuk meminimalisasi kerugian Negara maka perlu adanya pengembanganstrategi pengamanan wilayah perbatasan laut yang berbasis exspert system sebagai tool manajemenpengambilan keputusan. Sistem pakar (expert system) secara umum adalah sistim yang berusaha mengadopsipengetahuan manusia ke komputer, agar komputer dapat menyelesaikan masalah seperti yang biasa dilakukanoleh para ahli. Diharapkan dengan sistim ini, para militer yang bertugas di wilayah perbatasan laut Indonesiadapat menyelesaikan masalah yang ”sedikit rumit”, ”rumit” ataupun ”rumit sekali” tanpa bantuan para ahli,sedangkan untuk para ahli sistem ini bisa digunakan sebagai asisten yang berpengalaman. Aplikasi yangdikembangkan ini bertujuan untuk menentukan strategi pengamanan terhadap jenis-jenis gangguan yangterjadi di wilayah perbatasan laut Indonesia dengan memperhatikan tiga aspek ancaman yaitu: internal,eksternal dan internal-eksternal, dengan menggunakan pendekatan certainly factor (CP) kemungkinan ganguandan ancaman terhadap wilayah perbatasan laut Indonesia akan didapatkan nilainya (strategi)
Hepatitis B virus genotypes/subgenotypes in voluntary blood donors in Makassar, South Sulawesi, Indonesia
<p>Abstract</p> <p>Background</p> <p>Hepatitis B virus (HBV) genotype appears to show varying geographic distribution. Molecular epidemiological study of HBV in particular areas in Indonesia is still limited. This study was aimed to identify the prevalence of HBV genotype/subgenotype and mutations in basal core promoter (BCP) region in voluntary blood donors in Makassar, one of the biggest cities in east part of Indonesia.</p> <p>A total of 214 hepatitis B surface antigen (HBsAg)-positive samples were enrolled in this study. HBV genotype/subgenotype was identified by genotype-specific PCR method or direct sequencing of pre-S region. Mutations in BCP were identified by direct sequencing of the corresponding region.</p> <p>Results</p> <p>HBV/B and HBV/C were detected in 61.21% and 25.23% of the samples, while mix of HBV/B and HBV/C was found in 12.62% of the samples. Based on pre-S region, among HBV/B and HBV/C, HBV/B3 (95.00%) and HBV/C1 (58.82%) were predominant. Interestingly, HBV/D was identified in two samples (22.165.07 and 22.252.07). Complete genome sequences of two HBV/D strains (22.165.07 and 22.252.07) demonstrated that both strains belong to HBV/D6, and the divergence between the two strains were 1.45%, while divergences of both 22.165.07 and 22.252.07 strains with reference strain (<ext-link ext-link-id="AM422939" ext-link-type="gen">AM422939</ext-link>/France) were 2.67%. A1762T/G1764A mutation was observed in 1.96% and 5.36%, whereas T1753V mutation was found in 2.94% and 1.79% of HBV/B and HBV/C, respectively.</p> <p>Conclusion</p> <p>HBV/B and HBV/C are dominant in Makassar, similar to most areas in Indonesia. Mutations in BCP which might be associated with severity of liver disease are less common.</p
Effect of surrounding environment on atomic structure and equilibrium shape of growing nanocrystals: gold in/on SiO2
We report on the equilibrium shape and atomic structure of thermally-processed Au nanocrystals (NCs) as determined by high resolution transmission electron microscopy (TEM). The NCs were either deposited on SiO2surface or embedded in SiO2layer. Quantitative data on the NCs surface free energy were obtained via the inverse Wulff construction. Nanocrystals inside the SiO2layer are defect-free and maintain a symmetrical equilibrium shape during the growth. Nanocrystals on SiO2surface exhibit asymmetrical equilibrium shape that is characterized by the introduction of twins and more complex atomic defects above a critical size. The observed differences in the equilibrium shape and atomic structure evolution of growing NCs in and on SiO2is explained in terms of evolution in isotropic/anisotropic environment making the surface free energy function angular and/or radial symmetric/asymmetric affecting the rotational/translational invariance of the surface stress tensor
Tree islands enhance biodiversity and functioning in oil palm landscapes
In the United Nations Decade on Ecosystem Restoration1, large knowledge gaps persist on how to increase biodiversity and ecosystem functioning in cash crop-dominated tropical landscapes2. Here, we present findings from a large-scale, 5-year ecosystem restoration experiment in an oil palm landscape enriched with 52 tree islands, encompassing assessments of ten indicators of biodiversity and 19 indicators of ecosystem functioning. Overall, indicators of biodiversity and ecosystem functioning, as well as multidiversity and ecosystem multifunctionality, were higher in tree islands compared to conventionally managed oil palm. Larger tree islands led to larger gains in multidiversity through changes in vegetation structure. Furthermore, tree enrichment did not decrease landscape-scale oil palm yield. Our results demonstrate that enriching oil palm-dominated landscapes with tree islands is a promising ecological restoration strategy, yet should not replace the protection of remaining forests
Analisis Reaksi Pasar Sebelum dan Sesudah Pengumuman Akuisisi di Bursa Efek Indonesia (Bei)
Akuisisi merupakan sebuah kebijakan atau strategi yang bertujuan untuk melakukan perluasan usaha dengan mengambil alih kepemilikan Perusahaan lain. Motif Perusahaan dalam melakukan akuisisi akan berdampak pada reaksi pasar yang positif ataupun negatif. Perusahaan yang melakukan akuisisi dengan motif ekonomi akan direaksi positif oleh pasar, sedangkan motif non ekonomi akan direaksi negatif oleh pasar. Menguji perbedaan reaksi pasar sebelum dan sesudah pengumuman akuisisi yang dicerminkan dengan rata-rata abnormal return dalam periode lima hari sebelum dan lima hari sesudah pengumuman akuisisi merupakan tujuan dari penelitian ini. Metode pengambilan sampel menggunakan teknik purposive sampling dan menghasilkan 55 sampel Perusahaan yag melakukan akuisisi di Bursa Efek Indonesia. Teknik yang digunakan adalah uji wilcoxon signed rank test. Hasil yang ditemukan bahwa tidak terdapat perbedaan reaksi pasar yang signifikan sebelum dan sesudah pengumuman akuisisi. Penyebab utama hal ini bisa terjadi adalah karena ketidaktahuan investor akan motif Perusahaan melakukan akuisisi, sehingga investor ragu dalam mengambil keputusan investasi
Kata kunci: abnormal return, akuisisi, efisiensi pasar, rata-rata abnormal return.
 
Xtea Cryptography Implementation In Android Chatting App
Information security plays a significant role in information society. Cryptography is a key proof of concept to increasing the security of information assets and has been deployed in various algorithms. Among cryptography algorithms is Extended Tiny Encryption Algorithm. This study aims to describe a recent Android Apps to realize XTEA Cryptography in mobile form. In addition, a thorough example is presented to enable readers gain understanding on how it works within our Android Apps
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