Sifat Papan Partikel Daur Ulang Rendah Emisi Formaldehida

Emisi formaldehida dan sifat fisis-mekanis dari papan partikel yang direkat dengan urea formaldehida (UF) dapat mengganggu kesehatan, terutama jika digunakan di dalam ruangan dengan ventilasi terbatas. Untuk mengurangi emisi formaldehida, dapat digunakan suatu adsorben ke dalam perekatnya. Dalam tulisan ini diuraikan pengaruh penggunaan arang aktif dalam campuran perekat urea formaldehida terhadap emisi formaldehida dan sifat fisis-mekanis papan partikel daur ulang serta aspek ekonominya. Hasil penelitian menunjukkan bahwa pemakaian arang aktif mempengaruhi emisi formaldehida dan sifat fisis-mekanis papan partikel. Aplikasi arang aktif sebanyak 3% pada perekat urea formaldehida mampu mengurangi emisi formaldehida dan meningkatkan sifat fisis-mekanis papan partikel serta memenuhi persyaratan standar Indonesia dan Jepang, dan layak secara finansial

Analyst Forecasts and Price/Earnings Ratios

[Excerpt] Security valuation techniques have become increasingly sophisticated, as evidenced by advances in option pricing theory and Arbitrage Pricing Theory (APT). Despite the availability of these paradigms, the price/earnings (P/E) approach to security valuation has maintained its popularity among practicing security analysts. Much of this lasting popularity can be attributed to the apparent simplicity of the P/E approach and the difficulties inherent in implementing complex valuation models. To implement the P/E approach, analysts must estimate the appropriate P/E multiple, which typically requires the development of a model. Unfortunately, most of the P/E models that have been developed use ad hoc empirical tests and historical data. One notable exception is a study by Cragg and Malkiel, which tested a theoretical P/E model using analysts\u27 forecasts for a nonrandom sample of 175 large firms. This note extends the work of Cragg and Malkiel in two ways. First, it is not restricted to large firms; all firms with complete data are included in the empirical tests. Second, the model includes some factors not considered by other researchers

Two prototypes for medium rotation forestry harvesting

Five years old poplar (Populus spp.) plantation represents an interesting model of productivity. The most attractive characteristics of this energy crop are the handling flexibility, the high yield of biomass per area unit and the good quality of the chips obtainable. The mechanical harvesting of five-years old poplar plantations requires the use of specialized forest machineries such as harvester, feller, forwarder and chipper. Usually, after felling, the working phases consist of extraction, stacking and chipping. Generally, the last one is carried out in a “static phase”, where the product is taken from staked logs by using a hydraulic arm having a gripper that feed the chipping machine. In order to introduce technological innovations for the medium rotation forestry harvesting, the Consiglio per la Ricerca e la sperimentazione in Agricoltura, Unità di ricerca per l’Ingegneria agraria (CRAING) of Monterotondo (Rome, Italy) has developed a five years poplar cutwindrower and a self-propelled chipper equipped with a pick up system. The prototype of cut-windrower is a semi-trailed machine powered by a 95 kW tractor (at least). It mounts a cutting system and a double pincer with variable positioning. During the cutting phase the plant is grasped by the double pincer which conveys and unloads the stem along the inter-row. The trees are placed parallel to the progress of the tractor, but oriented in the opposite direction. The biomass windrowed is then chipped in a dynamic phase directly from the inter row using the self-propelled chipper equipped with the pick-up head. In the first tests, the cut-windrower has reached an operative working capacity of 0.22 ha h-1, with an operative production of 44 t h-1. On the other hand, the self-propelled chipper has showed an operative working capacity equal to 0.18 ha h-1, and an operative production of 35 t h-1 about. Both machines have shown good quality of the work performed and the results obtained indicates that the work phases could be simplified in order to reduce both the time of use and the harvesting costs

Pembuatan dan Pemanfaatan Arang Aktif sebagai Reduktor Emisi Formaldehida Kayu Lapis

Telah dilakukan penelitian pembuatan arang aktif dari serbuk gergajian kayu Acacia mangium Willd. Arang aktif yang dihasilkan digunakan sebagai reduktor emisi formaldehida pada perekat kayu lapis. Tujuan penelitian ini adalah untuk memanfaatkan limbah serbuk gergajian kayu mangium untuk dibuat arang aktif dan digunakan sebagai reduktor emisi formaldehida dalam perekat kayu lapis. Sebelum dibuat arang aktif, serbuk gergajian diarangkan dalam pada suhu 500OC. Arang yang dihasilkan diaktivasi secara kimia, fisika dan kombinasinya di dalam tungku baja tahan karat yang dilengkapi dengan pemanas listrik.Hasil penelitian menunjukkan bahwa kualitas arang aktif yang terbaik diperoleh dari serbuk gergajian kayu mangium yang diaktivasi dengan cara kombinasi oksidasi gas dan kimia dengan rendemen sebesar 53%, kadar air 4,33%, kadar abu 8,17%, kadar zat terbang 5,88%, kadar karbon terikat 83,77%, daya serap terhadap yodium sebesar 960,2 mg/g, metilien biru 135,0 mg/g, benzene 14,59%, kloroform 28,96% dan daya serap terhadap formaldehida sebesar 26,21%.Pencampuran arang aktif pada perekat kayu lapis mampu menurunkan emisi formaldehida pada perekat kayu lapis. Terbukti dari hasil uji emisi kayu lapis tanpa penambahan arang aktif menunjukkan emisi formaldehida sebesar 16,48 ppm, sedang emisi yang dihasilkan dengan penambahan arang aktif sebanyak 5% menurun menjadi 15,36 ppm, tanpa mempengaruhi ketegutan rekat kayu lapis

Monitoring Social Distancing by Smart Phone App in the effect of COVID-19

Social distancing measures are necessary for many infectious diseases that spreads through droplets and microdroplets. According to WHO, the preventive measure for COVID-19 is to follow strict social distancing. It is not easy to enforce social distance easily in a crowded region and people often not maintain sufficient distance with neighbours. Driven by the need for energy-efficient and cost-effective social distancing monitoring, this paper proposes Smart Social Distancing (SSD) mobile application based monitoring, which can predict the social distancing between two people assisted by mobile bluetooth and mobile camera. SSD involves two major steps to predict the social distance: first the pedestrian in the video frames is identified with the aid of Deep Learning (DL) and in the second step, distance between the two pedestrian is estimated through image processing techniques. The application can also be configured to calculate the distance using Bluetooth Low Energy (BLE) by calculating its received signal strength. The application demonstrates 85% accuracy on predicting the social distancing and alert the user using beep sound or alert messag

Peningkatan Mutu Arang Aktif Kulit Kayu Mangium

Penelitian ini bertujuan untuk mengetahui pengaruh suhu aktivasi, waktu aktivasi dan konsentrasi asam fosfat (H,PO,) terhadap hasil dan mutu arang aktif yang dihasilkan. Proses pembuatan arang aktif dilakukan dengan menggunakan retor yang terbuat dari baja tahan karat yang dilengkapi dengan elemen listrik pada suhu 750 dan 850°(dengan lama waktu aktivasi 90, 120 dan 150 menit Bahan pengaktif yang digunakan adalah larutan asam fosfat (H,PO,) dengan konsentrasi 0,0 dan 5,0%). Hasil penelitian menunjukkan bahwa kondisi optimum untuk membuat arang aktif dengan kualitas terbaik dihasilkan dari arang yang diaktivasi pada suhu 750°C selama 90 menit dengan konsentrasi H,PO, sebesar 5 %. Pada perlakuan ini rendemen yang dihasilkan sebesar 43,56%, kadar air 5,44%, kadar abu 8,01 %, kadar zat terbang 11,40%, kadar karbon terikat 80,60%, daya serap terhadap benzena 18,60% dan dengan daya serap terhadap yoclium sebesar 912,6 mg/g. Nilai daya serap yang diperoleh ini memenuhi syarat Standar asional Indonesia dan dapat digunakan untuk menjernihkan ai