PTFI Big Gossan Mine - Ventilation Design to Support the New Stope Sequence Strategy

Big Gossan (BG) mine is an open stope mine operated by PT Freeport Indonesia(PTFI). This mine started its development in 2006. Currently, the mine consists of 9 active levels, each level is designed with about 1 km footwall drift East-West. The production initiated in 2009, but the mine was temporarily shut down due to a company decision. Lately the mine has been re-activated since 2017 and will be pushed into its peak production in 2019, with 7000 tpd production rate. In order to meet with the production goal, 5 levels consisting of 34 at least production stopes are required on a yearly basis. The other strategy to meet the production goal is an improvement of stopes sequencing. Big Gossan Mine is ventilated by two parallel 1600kW exhaust Mixed-Flow fans.This paper presents the ventilation plan and design to support the improved stope sequence until peak production, include the analysis of ventilation design criteria, ventilation network modeling, infrastructure required, possibility of main fans upgrade and other ventilation open stope mine challenges

ECONOMIC ANALYSIS OF IRISH POTATO (Solanum tuberasum) PRODUCTION UNDER IRRIGATION SYS- TEM IN KATSINA METROPOLIS, KATSINA LOCAL GOVERNMENT AREA, KATSINA STATE

A survey on economics analysis of Irish Potato (Solanum tuberasum) Production under irrigation sys- tem in Katsina Metropolis Katsina Local Government Area was carried out. Six communities were purposively selected due to the production of Irish potato. The communities were Kofar Sauri, Kofar Durbi, Kofar Marusa, Filin Samji, Rafukka and Yammawa. A simple random sampling was employed in selecting the farmers were by ten (10) farmers were randomly selected from each community which gave a total of sixty respondents. The data were obtained using structured questionnaire and sub- jected to descriptive statistics, gross margin and net farm income analysis. The research describes the socio economic characteristic of the respondents in which the respondents were within the mean age of 41 years. The result also showed hundred percent of the respondents were male, 66.6% were mar- ried, 30%, 31.6%, 33.3% and 5% had qur«¤??anic, primary, secondary and tertiary education respectively. The result also showed that 90% of the respondents«¤?? source their initial income for production of Irish potato from personal saving and 48.3% source information from mass media. The research also de- scribed the production characteristic of the respondents were majority (51.6%) cultivate 0.2-0.4ha, 81.6% acquired their land by inheritance, 88.3% practice sole cropping and 48.3% used family labor. Net Farm Income analysis revealed that Irish potato production in the study area is profitable with Net Farm Income of N5798.83, «¤?¢Ã21555.35 and «¤?¢Ã65399.48 for 0.2-0.4ha, 0.5-0.7ha and 0.8-1ha. The result further reveals that manure and fuel contributed toward the output for 0.2-0.4ha, manure, fuel, water and labour contributed for 0.5-0.7ha and manure, water and labour for 0.8-1ha. The result also identified some constraints to Irish potato production such as inadequate fertilizer, poor storage facili- ties, pest and diseases, inadequate extension advice, poor canal maintenance, inadequate capital, poor cooperation, adulteration of farm input, and marketing problem. Conclusively, net farm income result shows that Irish potato production is profitable in the study area. It is recommended that re- search into way of improving the method of storage should be promoted

Mapping of beef cattle value chain actors in selected states of North-West Zone, Nigeria

This study was aimed at mapping of the various actors of the beef cattle value chain and their functional roles. A multi-stage sampling technique was employed in the selection of the respondents. A sample size of 576 value chain actors consisting of 120 beef cattle farmers, 60 beef cattle traders, 36 butchers, 60 raw beef marketers, 60 processed beef marketers and 240 consumers. The study made use of primary data which were obtained through the use of a computer-aided personal interview (CAPI) version of survey instrument rather than a paper-based questionnaire. Data were collected on production, marketing and consumption components of beef cattle value chain activities. Descriptive statistics was used to analyze the data. The results revealed that beef cattle value chain actors do not perform only one primary value chain activity but perform other value chain activities as secondary activities. This multiplicity of functions carried out by some of the beef cattle value chain actors implies that the beef cattle value chain is not a linear and straightforward chain where each actor is specialized in one activity. It can be concluded that beef cattle value chain activities involve a complex interrelationship in the activities carried out by the different actors in the physical flow of beef from farm to fork. It is therefore recommended that government should intervene in the area of linking actors in the value chain to prospective markets in order for the actors to benefit from the various activities

A study of vowel alternation in Hausa.

This study aims at finding out the particular phonetic contexts within which the alternation of [i], [i] & [u] in Hausa takes place in an utterance, and where it does not. It also aims at establishing the underlying forms amongst these vowels as well as identifying the underlying causes for the alternation or non-alternation. The work is divided into ten chapters: Chapter One introduces the work. It discusses the Hausa consonants based on the standard dialect, the vowels as shared by both the standard and non-standard dialects, and their phonological status. Chapter Two is basically divided into two sections, with the first one discussing the 'general' type of vowel alternation (dialectal and non-dialectal), and the second section dealing with the alternation of [i], [i] & [u] 'specific' in the standard dialect. Chapters 3, 4, 5, 6 & 7 look into the [i/i/u] alternation in the Zaria, Bauchi, Daura, Katsina & Sokoto dialects respectively, all relative to the standard. Chapter Eight is devoted to establishing the underlying forms in the words where a labial and/or coronal precede(s). Chapter Nine examines the -ij- and -uw- sequences in relation to the alternation under consideration. Finally, Chapter Ten sets out the conclusions reached in the study

International survey of Cronobacter sakazakii and other Cronobacter spp. in follow up formulas and infant food

A coordinated survey for Cronobacter and related organisms in powdered infant formula, follow up formula and infant foods was undertaken by 8 laboratories in 7 countries in recognition of and in response to the data needs identified in an FAO/WHO call for data in order to develop global risk management guidance for these products. The products (domestic and imported) were purchased from the local market and were categorised according to their principle ingredients. A total of 290 products were analysed using a standardised procedure of pre-enrichment in 225 ml Buffered Peptone Water (BPW), followed by enrichment in Enterobacteriaceae Enrichment (EE) broth, plating on the chromogenic Cronobacter Druggan–Forsythe–Iversen (DFI) agar and presumptive identification with ID 32 E. Presumptive Cronobacter isolates were identified using 16S rRNA gene sequence analysis. Aerobic plate counts (APC) of the products were also determined on nutrient agar. Fourteen samples had APC > 105 cfu/g, 3 of which contained probiotic cultures. C. sakazakii was isolated from 27 products; 3/91 (3%) follow up formulas (as defined by Codex Alimentarius Commission), and 24/199 (12%) infant foods and drinks. Hence C. sakazakii was less prevalent in follow up formula than other foods given to infants over the same age range. A range of other bacteria were also isolated from follow up formulas, including Acinetobacter baumannii, Enterobacter cloacae, Klebsiella pneumoniae, Citrobacter freundii, and Serratia ficaria. There was significant variation in the reconstitution instructions for follow up formulas. These included using water at temperatures which would enable bacterial growth. Additionally, the definition of follow up formula varied between countries

Machinability Evaluation of Nanoparticle Enriched in Vegetable-Based-Nanofluids for Machining Process

Vegetable oil had been study to replace mineral based oil as metalworking fluids (MWFs) as it is non toxic, bio-degradable and environmental friendly. Due to vegetable oil’s high viscosity and poor thermal conductivity, some improvement had been applied to vegetable oil such as chemically modified and the addition of additives. The aim of this study to evaluate the machining performance of modified jatropha oil (MJO) with nanoparticle additives of 0.025wt% copper oxide(Cuo) (MJOc) and 0.025wt% hexagonal boron nitride(hBN) (MJOh) as metalworking fluids. The machining performance of MJOc and MJOh were compared with the commercial synthetic ester (SE) through turning process in terms of cutting temperature, surface roughness, tool life and tool wear. The result show that the machining performance of MJOc and MJOh were better compared to SE. In terms of cutting temperature and surface roughness, MJOh shows better maching performance compared to MJOc. In addition, MJOh had same tool life performance with SE which is at cutting length of 6000mm and machining time of 42 minutes. In conclusion, the overall best machining performance is MJOh (MJO+0.025wt% hBN) and has a potential as sustainable MWFs in lubricant market

Ocean warming and acidification detrimentally affect coral tissue regeneration at a Mediterranean CO2 vent

Among the main phenomena that are causing significant changes in ocean waters are warming and acidification, largely due to anthropogenic activities. Growing evidence suggests that climate change is having more substantial and rapid effects on marine communities than on terrestrial ones, triggering several physiological responses in these organisms, including in corals. Here we investigated, for first time in the field, the combined effect of increasing seawater acidification and warming on tissue regeneration rate of three Mediterranean scleractinian coral species characterized by different trophic strategies and growth modes. Balanophyllia europaea (solitary, zooxanthellate), Leptopsammia pruvoti (solitary, non-zooxanthellate) and Astroides calycularis (colonial, non-zooxanthellate) specimens were transplanted, during a cold, intermediate, and warm period, along a natural pH gradient generated by an underwater volcanic crater at Panarea Island (Mediterranean Sea, Italy), characterized by continuous and localized CO2 emissions at ambient temperature. Our results show a decrease in regenerative capacity, especially in the zooxanthellate species, with increasing seawater temperature and acidification, with demonstrated species-specific differences. This finding suggests that increasing seawater temperature and acidification could have a compounding effect on coral regeneration following injury, potentially hindering the capacity of corals to recover following physical disturbance under predicted climate change

Deductive synthesis of recursive plans in linear logic

Linear logic has previously been shown to be suitable for describing and deductively solving planning problems involving conjunction and disjunction. We introduce a recursively defined datatype and a corresponding induction rule, thereby allowing recursive plans to be synthesised. In order to make explicit the relationship between proofs and plans, we enhance the linear logic deduction rules to handle plans as a form of proof term

Funding Arrangements for Small and Medium Scale Enterprises (SMEs) in Nigeria: An Assessment

Small and Medium Scale Enterprises have been fully recognized by governments and development experts as the main engine of economic growth and a major factor in promoting development. They not only contribute significantly to improved living standards, employment generation and poverty reduction but also bring about substantial domestic or local capital formation and achievement of high levels of productivity and capability. A major gap in Nigeria’s industrial development process in the past years has been the absence of a strong and virile SME sub-sector. This study seeks to generally appraise and analyze the operating environment and circumstances of Small and Medium Scale Enterprises in Nigeria with a view to actually identifying why SMEs are not playing major roles in the Nigerian economy as in other economies. The random sampling method was employed and responses to the questionnaire were complemented with personal interviews of key operators. Analysis was undertaken using the Statistical Package for Social Sciences (SPSS). Findings revealed that SMEs have performed below expectation in the development of Nigeria economy due to a combination of factors. Thus, the paper recommends that the realization of these require a paradigm shift from paying lip service to a practical radical forward approach to issues and focus on this all-important sector of the economy and realistically addressing the identified problems by the key operators