Koordinasi Rele pada Jaringan Transmisi 150 KV

Power transmission system is of one component in the supply of electricity. Then it takes one of transmission system good. To maintain of transmission system good needed protection system accordance with the requirements of protection . protection system functioning of to localize disturbance as small as possible . protection system of transmission normally using of distance relay and OCR-GFR relay. distance relay serves as a main security and OCR-GFR for as backup. calculation of short circuit and relay coordination using digsilent program 14.1.3. based on the results of calculations and simulations showed that the distance relay coordination is good and necessary for resetting the relay OCR-GFR due to changes in short circuit

Analisa Pengaruh Sambaran Petir pada Jaringan Distribusi 13,8 KV di BOB PT. BSP - Pertamina Hulu Bandar Pedada Menggunakan Software ATP-EMTP

The purpose of this paper is to analize the effect of indirect lightning strikes on the 13.8 kV distribution network at BOB PT. BSP - Pertamina Hulu Bandar Pedada by using ATP-EMTP. Maximum induced voltage of indirect lightning is computed by using Rusck theory, then indirect lightning strikes are simulated by using ATP-EMTP. In this paper, five conditions are simulated. The first condition is the distribution line without the indirect lightning strikes with 15 kV lightning arresters and the ground wire is installed, the second condition is the indirect lightning strikes without the 15 kV lightning arresters and ground wire, the third condition is indirect lightning strikes with the ground wire is installed and without the 15 kV lightning arrester, the fourth condition is the indirect lightning strikes with 15 kV lightning arresters are installed and without the ground wire, and the fifth condition is the indirect lightning strikes with the 15 kV lightning arresters and ground wire is installed. The simulation results show that the ground wire is able to reduce the effect of the induced voltage from the indirect lightning strikes, the 15 kV lightning arresters are able to reduce the effect of the induced voltage from the indirect lightning strikes, and the best results are obtained when the ground wire and the 15 kV lightning arresters are installed on the distribution line

Evaluasi Sistem Proteksi Petir pada Tower PT. Sampoerna Telekomunikasi Indonesia (Ceria) Pekanbaru

Lightning occurs because there is a difference of potential between the cloud and the earth or by other clouds. Lightning caused a lot of harm to people and damage to the equipment. Some places with the high rate of lightning strikes (frequency and intensity) of being the first priority in the use of the installation of lightning protection. Tropical countries like Indonesia generally have a high lightning day each year, including in the area of Pekanbaru. This paper proposes to evaluate lightning protection system in PT. Sampoerna Telekomunikasi Indonesia (Ceria) Pekanbaru. Improvement of lightning protection system is made through a Rolling Sphere Method. The result of the data shows that the lightning protection system in PT. Sampoerna Telekomunikasi Indonesia (Ceria) Pekanbaru was already capable of protecting the Base Station Transceiver (BTS) from lightning strikes. This results is proven to indicate that lightning protect is improved

Kajian Perancangan Sistem Penangkal Petir Eksternal pada Gedung Pusat Komputer Universitas Riau

Pekanbaru City is a city located in an area that has a large enough lightning density is equal to 136 days per year with thunder, lightning strikes the ground density (Ng) reached 19.5128 strike/km2/year. Computer Center Building University of Riau is the center of Riau University data, built with a size of 47 m x 21 m x 12.4 m. In the design of the external lightning protection on buildings, there are some technical requirements that need to be considered such as; identifying the needs of a lightning protection system based PUIPP, determining the level of protection lightning protection system based on IEC 1024-1-1, finial selection, determination down conductor and grounding system. From the analysis of hazard assessment, which is an interesting area of 10395.41 m² lightning strike, the possibility of building struck by lightning strikes per year with 0,203 lightning protection system efficiency 0.507. Based on data and analysis can then be described in the protected areas of the Computer Center building good front, side, rear and top. The results obtained showed that the Computer Center building has a poor level of efficiency is based on the analysis of the rolling sphere method

Identifikasi Kegagalan Peralatan Proteksi pada Jaringan Distribusi PT. Pln Gardu Induk Garuda Sakti Menggunakan Anfis (Adaptive Neural Fuzzy Inference System)

The purpose of research is to identification process of faulty protection devices using operating status of circuit breaker. Technique used for the identification process is Adaptive Neuro-Fuzzy Inference System (ANFIS). ANFIS is a method that combines fuzzy logic and neural network. Design ANFIS needs input data in form of voltage, current and operating status of circuit breaker (1 and 0) for training process. Input data produces by output of distribution system simulation in ETAP, meanwhile operating status of circuit breakers in binary numbers, one and zeros are interpreted as operating and non-operating devices, respectively. The training result gives worth accuracy so that can be use for predicting operating status of circuit breaker. If faulty device has been identified so system restoration can be done immediately

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Pengaruh Suhu dan Lama Blansing terhadap Penurunan Kesegaran Filet Tagih Selama Penyimpanan pada Suhu Rendah

Penelitian mengenai pengaruh suhu dan lama blansing terhadap penurunan kesegaran filet tagih selama penyimpanan pada suhu rendah telah dilakukan. Tiga taraf perlakuan suhu blansing, 80o, 90o, dan 100oC dan tiga taraf lama blansing, 1, 3 dan 5 menit. Paramater yang diamati selama penyimpanan filet tagih pada suhu rendah adalah populasi bakteri pembusuk, pH dan susut bobot. Hasil penelitian menunjukkan bahwa filet yang diblansing pada suhu 80oC selama 3 menit mampu menghambat penurunan kesegaran paling baik dengan populasi mikroba pada penyimpanan hari ke-10 sebanyak 6 x 10% CFU, peningkatan pH menjadi 6.55 pada hari ke-4 dan susut bobot pada hari ke-10 sebesar 4 persen