Siti Latifah

Bio: Siti Latifah is an academic researcher from University of North Sumatra. The author has contributed to research in topics: Toona sureni & Biomass. The author has an hindex of 5, co-authored 43 publications receiving 98 citations. Previous affiliations of Siti Latifah include Tanjungpura University & University of Indonesia.

Prinsip-Prinsip Dasar Analytical Hierarchy Process

Abstract: Sumber kerumitan masalah pengambilan keputusan bukan hanya ketidakpastian atau ketidak sempurnaan informasi. Penyebab lainnya adalah faktor yang berpengaruh terhadap pilihan-pilihan yang ada, beragamnya kriteria, pemilihan dan jika pengmbilan keputusan lebih dari satu pilihan. Di dalam games theory dibahas masalah keputusan jika sumber kerumitannya ketidaksempurnaan informasi dan adanya lebih dari satu pengambilan keputusan yang sedang bersaing. Jika sumber kerumitan itu adalah beragamnya kriteria, maka Analytical Hierarchy Process (AHP) merupakan teknik untuk membantu menyelesaikan masalah ini. AHP diperkenalkan oleh Thomas L. Saaty pada priode 1971-1975 ketika di Wharton School. Dalam perkembangannya, AHP tidak saja digunakan untuk menentukan prioritas pilihan-pilihan dengan banyak kriteria, tetapi penerapannya telah meluas sebagai model alternatif untuk menyelasaikan bermacam-macam masalah; seperti memilih portfolio, analisis manfaat biaya, peramalan dan lain-lain. Pendeknya, AHP menawarkan penyelesaian masalah keputusan yang melibatkan seluruh sumber kerumitan seperti yang didefenisikan diatas. Hal ini dimungkinkan karena AHP cukup mengandalkan pada intuisi sebagai input utamanya, namun intuisi harus datang dari pengambilan keputusan yang cukup informasi dan memahami masalah keputusan yang dihadapi. Pada dasarnya, AHP adalah suatu teori umum tentang pengukuran. Ia digunakan untuk menemukan skala rasio baik dari perbandingan pasangan yang diskrit maupun kontinyu. Perbandingan-perbandingan ini dapat diambil dari ukuran aktual atau dari suatu skala dasar yang mencerminkan kekuatan perasaan dan prefensi relatif. AHP memiliki perhatian khusus tentang penyimpangan dari konsistensi, pengukuran dan pada keteragantungan di dalam dan diantara kelompok elemen strukturnya. Di dalam tulisan ini diberikan prinsip-prinsip dasar AHP melaui contoh penerapannya untuk menyelesaikan masalah pengambilan keputusan. II. PRINSIP-PRINSIP DASAR ANALYTICAL HIERARCHY PROCESS (AHP) Skala ukuran panjang (meter), temperatur (derajat), waktu (detik) dan uang (rupiah) telah digunakan dalam kehidupan sehari-hari untuk mengukur bermacam-macam kejadian yang sifatnya fisik. Kita tahu bahwa penerapan seperti itu dapat diterima secara umum. Pertanyaan adalah apakah kita dapat memperluas dan membenarkan penggunaan sekala tersebut secara beralasan dan mudah dipahami untuk mencerminkan perasaanperasaan kita pada bermacam-macam persoalan sosial, ekonomi dan politik? Sulit dibayangkan, sebab disini lebih cocokl bila digunakan suatu ukuran lain yang lebih

Spatial Analysis on Distribution of Green Belt to Reduce Impacts Of Climate Change in Medan City, North Sumatra

Abstract: Medan, the capital city of North Sumatra Province, which consists of 21 sub-districts, encompasses 26.510 ha or 3.6% of the total province area. One way to reduce emissions and air pollution in urban areas is to create open green space. This study aimed to analyse and map trees in the green belt of Medan City as an effort to alleviate negative effects of climate change. Global Positioning System (GPS) was used to record the coordinate’s points of trees. The Geographic Information System (GIS) was used to analyze the distribution of green belt. Tree inventory was conducted by census method to analyze the composition and density of tree species. The results showed that most of the green belt was dominated by trees with species composition including the category of very low (84.4%). Tree density levels were dominated by very tightly category (78.1%). The Location of green belt with the highest density level was Jalan Sunggal, Medan Sunggal Sub District with a value of 1,893.75 trees/ha (very tightly). Pterocarpus indicus was the highest Importance Value Index (88.47%), followed by Switenia macrophylla (57.30%) and Oreodoxa regia (53.64%). Species diversity classified as average category (1.45). There are similarity of plant community among sampled green belt locations. The map of green belt resulted from this research could be used as one of the basis in a decision making to reduce negative effects of climate change in Medan city. As one of the largest cities in Indonesia, the existence of green belt area in Medan City is a must. Therefore, it is necessary to develop green belt area in several sub districts in Medan City.

Estimation of Aboveground Tree Biomass Toona Sureni and Coffea Arabica in Agroforestry System of Simalungun, North Sumatra, Indonesia

Abstract: Latifah S, Muhdi, Purwoko A, Tanjung E. 2018. Estimation of aboveground tree biomass Toona sureni and Coffea arabica in agroforestry system of Simalungun, North Sumatra, Indonesia. Biodiversitas 19: 670-675. Agroforestry is an ecologically and environmentally sustainable land use that offers great promise to carbon (C) sequestration. Forests play a significant role in reducing greenhouse gas emissions through maintaining current carbon stores and by increasing the rate of carbon sequestration. Vegetation carbon stocks are necessary to be quantified to evaluate the carbon sequestration potential in the ecosystem. Reasonable methods for estimating tree biomass and carbon storage on forest land are increasingly crucial given concerns of global climate change. This study aimed to evaluate C sequestration potential by agroforestry in North Sumatra Indonesia. This study was conducted at the Agroforestry system in Aek Nauli, Simalungun District, North Sumatra. Data collection for primary data was done through a field survey. The present study was carried out to determine above ground tree biomass of Toona sureni (Blume) Merr and Coffea arabica. Data retrieval of T. sureni and C. arabica was done by non-destructive sampling by measuring the diameter at breast height (dbh). The results showed that the potential of average above-ground biomass and carbon storage of T. sureni and C. arabica was 6.25 t ha-1 and 2.88 C t ha-1, respectively. Total aboveground biomass of Toona sureni and C. arabica in the study area was 93.75 ton, while total of carbon storage was 43.16 ton

Carbon Sequestration Potential in Aboveground Biomass of Hybrid Eucalyptus Plantation Forest

Abstract: Forests are a significant part of the global carbon cycle. Forests sequester carbon by conducting photosynthesis, which is the process of converting light energy to chemical energy and storing it in the chemical bonds of sugar. Carbon sequestration through forestry has the potential to play a significant role in ameliorating global environmental problems such as atmospheric accumulation of GHG's and climate change. The present investigation was carried out to determine carbon sequestration potential of hybrid Eucalyptus. This study was conducted primarily to develop a prediction model of carbon storage capacity for plantation forest of hybrid Eucalyptus in Aek Nauli, Simalungun District, North Sumatera. Models were tested and assessed for statistical validity and accuracy in predicting biomass and carbon, based on determination coefficient (R) and correlation coefficient (r), aggregative deviation percentage (AgD), and the average deviation percentage (AvD). The best general model to estimate the biomass of hybrid Eucalyptus was Y = 1351,09x^0,876. e^(0,094). Results showed that hybrid Eucalyptus had an average above-ground biomass in year 0 (the land without the eucalyptus trees) up to year 3 as large as 1.36, 11.56, 43.18, and 63.84 t ha. The carbon content of hybrid Eucalyptus were 0.61, 5.2, 19.43 t^(-1), and 28,73 t^(-1) C ha while the carbon sequestration potential were 2.23, 19.08, 71.31, and 105.43 t^(-1) CO ha^(-1) respectively.

Valutazione delle risorse forestali a livello globale

Abstract: The results of the Forest Resources Assessment 2000 carried out by FAO are synthetically presented and discussed. The world forest coverage is estimated equal to 38.6 million km 2 . The comparison of the estimates from the period 1990-2000 with those from the period 1980-1990 points out a certain general deceleration of the rate of net deforestation, that currently involves around 9 million hectares every year. However, the annua1 loss of tropical forests is still very large, while temperate and borea1 forests are in expansion. Overall, FRA2000 produced a relevant effort to compensate the existing technical, institutional and financial constraints and shortcomings for monitoring the world forest resources. The need to increase the quality and the frequency of forest surveys, both at national and international levels, s t a stands as a major issue to cope with.

Landasan bimbingan dan konseling di institusi pendidikan

Abstract: Landasan bimbingan dan konseling di Institusi Pendidikan merupakan bagian yang integral dan penting untuk dibicarakan. Karena hal ini merupakan dasar atau pondasi bagi konselor atau guru Bimbingan dan Konseling (guru BK) dalam menyelenggara kan layanan bimbingan konseling di Indonesia, khususnya di Institusi pendidikan. Landasan tersebut mencakup landasan hukum (yuridis formal), landasan filosofis, landasan psikologis, landasan sosial budaya dan landasan ilmu pengetahuan dan teknologi.

Time-delayed SIS epidemic model with population awareness

Abstract: This paper analyses the dynamics of infectious disease with a concurrent spread of disease awareness. The model includes local awareness due to contacts with aware individuals, as well as global awareness due to reported cases of infection and awareness campaigns. We investigate the effects of time delay in response of unaware individuals to available information on the epidemic dynamics by establishing conditions for the Hopf bifurcation of the endemic steady state of the model. Analytical results are supported by numerical bifurcation analysis and simulations.