Hasanuddin University Graduate School: Open Journal Systems
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Beneficiation Study of Iron Ore from Pakke area of Bontocani Subdistrict, Bone Regency of South Sulawesi, Indonesia Using Roasting and Magnetic Separation Methods
Get PDFThis study aims to examine the characteristics and analyze the magnetic beneficiation process of iron ore from Pakke area of Bontocani subdistrict, Bone regency. Mineralogical analysis using Microscopic and XRD (X-Ray Diffraction) methods indicate that iron ore sample is composed of quartz (SiO2), calcite (CaCO3), goetite (FeO.OH), hematite (Fe2O3) and magnetite (Fe3O4). The results of chemical analysis by means of XRF (X-Ray Fluorescence) method showed that sample consists of 30.49% Fe2O3, 42.39% SiO2, 10.03% MnO and 1.19% As2O3. Each feed fraction was separated using a low-intensity drum magnetic separator. The higherst Fe2O3 content of concentrate product was 54.21% and recovery of 75.31% which was achieved at the size fraction of (-180 + 150) μm. The addition of wood charcoal as reducing agent by 3% during roasting process at the temperature of 950oC for 90 minutes has led to increase the Fe2O3 content in concentrate product about 63.791% but recovery was slightly recerease to about 65.20%. It was shown that the size fraction of (-180 + 150) μm is better feed in this experiment
ATTITUDES TOWARDS CATCHING AND KILLING THE YAMABIRU (LAND LEECH) IN THE TENRYU AREA, JAPAN
Get PDFRecently, yamabiru, or land leeches (Haemadipsa zeylanica japonica), have proliferated in prefectures across Japan. Since it is unlikely that they will disappear from the living spaces, fields, and forests in which humans live and work, people living in the new contact zones have devised methods to coexist with them. The field research was conducted in 2017 and 2018 in C Township in the Tenryu area. Like many rural areas in Japan, C Township is facing the challenges of depopulation and ageing, and is home to a group of residents who aim for local revitalization. The participatory observation of leech-catching, an activity practiced by the group members who dare to use their hands to kill yamabiru instead of chemicals, provides several implications regarding ethical attitudes and the role of the human body. This paper argues that the members do not behave as victims suffering from the damage caused by yamabiru and do not kill them out of anger or discomfort. Instead, by behaving as an assailant and seeking out the concrete feeling of killing by direct contact, the members attempt to control their disastrous impact on other creatures and the environment. This behavior invites us to pay closer attention to the role of the human body and of bodily interaction as a sensory tool to coexist with other creatures in the Anthropocene, an era full of risks and uncertaintyÂ
ASSESSMENT OF GENDER DIFFERENCES IN PRODUCTIVITY AMONG RURAL HOUSEHOLDS IN SOUTH WEST, NIGERIA
Get PDFIncrease in productivity across gender line is one of the necessary conditions for sustainable level of development in the rural areas. This study assessed the differences in productivity of men and women in rural households in Southwest, Nigeria. Average and marginal productivity of women and men were assessed. Gender-disaggregated data were obtained through structured questionnaires. Using multi stage sampling approach, a total of 197 and 148 men and women rural households were randomly sampled. Cobb Douglas production function was used to analyse differentials in productivity between women and men. The results showed that women have access to marginal and small pieces of land. Men with access to improved technology have significantly (p < 0.05) higher productivity per unit of most of the inputs available. Also, the result indicates that the estimated average productivities of women are signiï¬cantly lower than those of men. Furthermore, ownership of land has a significant positive influence on the estimated productivity of men more than women. Education which is another gender factor and a measure of human asset and managerial capacity significantly (p < 0.05) increased the productivity of men (β = 0.11, t = 3.04) and women (β = 0.07, t = 3.86). In order to raise productivity and impacts development agenda for the rural sector, it would be better for women to keep the variable resource in surplus rather than utilizing it in a fixed resource contrary to what is obtainable for men
STRATEGI PENGEMBANGAN USAHATANI PADI SAWAH DI KAWASAN PESISIR
No full textThis research aims to determine (1) internal factors, which become the strengths and weaknesses of rice farming in Kuri Caddi village (2) External factors, which become the opportunitie sand threats of rice farming inKuriCaddi. (3) Strategy development of rice farming in coastal area of Kuri Caddi, Sub-district of Nisombalia, District of Marusu, Regency of Maros. The result of this research identifies that there werefour aspects of internal and external factors that influenced the development of rice farming in Kurri Caddi, which were strengths, weaknesses, opportunities and threats.The strengths consists of (1) the available workers (2) cultivable land (3) farming experiences(4) farmer’s productivity. The weaknesses consists of (1) Uncertified seed (2)unbalanced fertilizer use(3) bad-timing tillage and (4) farmers are reluctant to use new farming innovation.The opportunities consists of (1) the emergence ofnew forms of employment, (2) group of farmerthat provide the distribution of farming supports and facilitiesand (3)strong community self-help. Threats consists of (1) problems of road transportation facilities (2) natural disasters and  (3)attack of pests and diseases. Strategy development that can be new innovations such as by using certifies and implementing the jajar legowo system, with achieved score 5,49. Keywords: Rice Farming in Coastal Area; Strategy Development
Designing New Strategy for Enhancing Robusta Coffee Production: An Application of Interpretative Structural Modeling
Get PDFOne of the causal factors affect coffee production declining in Indonesia is the decline in harvest area of coffee plants. The decline in the area of coffee farming is caused by the shift of farmers from coffee to other commodities, such as corn, vegetables and fruit. The research was conducted to determine new strategic steps in order to enhance robusta coffee production. To achieve the research objectives, Interpretative Structural Modeling (ISM) analysis and modeling techniques are carried out. This modeling technique does not require a large sample, so the sample used in this study is limited to 22 people from several related agencies. Data processing in research is carried out according to the needs of Interpretative Structural Modeling (ISM) analysis. The results show that the new strategy in developing Robusta coffee production is (1) rehabilitation of coffee plants, (2) rejuvenation of coffee plants, (3) selection of superior coffee varieties, (4) provision of farming roads, (5) coffee price stabilization, (6) intensification of coffee plants, (7) pest control, and (8) increased knowledge of farmers. These new combinations strategy can be strongly expected to enhance robusta coffee production in the country
Amine-functionalized MCM-48 as Adsorbent of Zn2+ and Ni2+ Ions
Get PDFA compound, 3-aminopropyltrimetoxy silane, has been used to modify mesoporous silica, MCM-48. The modified silica (NH2-MCM-48) was utilized to remove Zn2+ and Ni2+ ions from solutions. The mesoporous material was synthesized in the alkaline solution. Characterization of the unmodified materials was conducted by X-ray diffraction and FT-IR spectroscopy. The ions adsorbed on NH2-MCM-48 were studied at various pHs, contact times and initial ions concentrations. An Atomic Absorption Spectrophotometer (AAS) measured the ions content in the solution.. Pseudo-first-order and pseudo-second-order models performed the kinetic adsorption. The adsorption isotherm was examined by Langmuir and Freundlich isotherms. The result found that optimum contact time for the adsorption of Zn2+ ion was lower than that for Ni2+ ion. The adsorption followed the pseudo-second-order model with the adsorption rate of 4.56x10-2 g mg-1 min-1 for Zn2+ ion and 7x10-4 g mg-1 min-1 for Ni2+ ion. The optimum pH was 6 and 4 for Zn2+ and Ni2+ adsorption, respectively. The uptake of both ions from solutions by NH2-MCM-48 fixed better the Langmuir than the Freundlich model with the adsorption capacity of 0.55 and 0.43 mmol g-1, correspondingly. This research work provides valuable information on the interaction between the ions and the functional group of adsorbent
Modelling Maintenance System of a Fishing Vessel Using Markov Process Method
Get PDFReliability analysis on a ship system have developed as the increasing demand on the level of safety and reliability of the ship design. There are some significantly important of ship systems which support the ship operationalization. Failure on one system component can influence the functionality of the respective system and even can damage the whole ship function. If this is happen, the safety of the passengers and cargoes on the ship will be threatened. A comprehensive evaluation on the ship systems must be conducted so that the failure level of the system can be predicted. For the safety of the maintenance action on a system, model of the ship system maintenance must be designed. One common approach to be used on a maintenance modelling of a system is markov approach or markov modelling. The final result of the appoach is an availability index of a system as a consequences of the ship system maintenance. Output from this approach will become input for designing ship system maintenance strategy. This paper discusses the use of markov process approach in modelling maintenance of a ship system. In the final part of the paper, a maintenance modelling case for a ship fresh water cooling system is presented
Overpressure Petroleum System Analysis Northern Area Field ‘’X’’ East Kalimantan
No full textAnalysis method of overpressure was known in dilling operation to obtain drilling strategy information. Mahakam Deltaic as main giant gas producer in Indonesia specially located on northern area was studied to gain information about pressure profile area. Analysis Normal Compaction, Overburden Gradient using Eaton and Bower’s method from wireline data is used to define pressure profile. Correlation with drilling event hopefully could established the prediction of pressure profile while drilling without supporting from wireline data.  Three pressurre profile area has been detected by combination log data and drilling event which are top lower pressure signature by high gas, transition zone signature by occured gas cut mud due to high gas and hard ovepressure signature by issued well control
Study on Fatigue Prediction of Composite Seaplane Float Based on The Porpoising Model Test Data
Get PDFAmphibious aircraft as an alternative mode of transportation to accelerate connections between small islands without building ground runway infrastructure. Amphibious aircraft floater is one of the important technological components that supports aircraft takeoff at sea. For that reason, the floater must be designed that is strong, effective and safe in the operation of amphibious aircraft. In this paper, the prediction method begins with selecting the heave and pitching data from the model test when float model experienced porpoising. These data is then used to calculate those coupled forces that act on the float structure which made from composite material. By knowing those forces the principal stresses that act on the structure also can be calculated. Therefore the stress time history on the float structure can be obtained. This stress time history is then applied to Palmgren – Miner formula that based on SN-Curve of the composite material to predict the life of the composite float. From this study it is found that the fatigue life of the floats is approximately 11 years with the assumptions of the seaplane experiencing takes off 4 hours daily
ISSUES OF WATER RESOURCE MANAGEMENT IN CHINA: IMPLICATIONS ON AGRICULTURE AND FOOD SECURITY IN THE GUANGXI PROVINCE OF SOUTH CHINA
Get PDFDespite China’s great stride in technology development and economic recovery, water remains a major issue of concern. Water has a direct impact on agriculture and food production, hence, water management is critical to achieving food security. This paper reviews in a broader perspective the relationship between water resource management and food security in China, and assesses water resource management interms of water use, pollution and influence of government policies, as well as social and economic systems. It also highlights the challenges of water resource management and its implications on agriculture and food security in the Guangxi province of South China. The review also sets a background upon which further studies and frameworks could be developed to help provide a sustainable solution to regional water management challenges, with a view to achieving improved agricultural production and food security in China and other countries with similar issues. Thus, in the growing quest for economic growth, and owing to the growing need for water in the country, the government of China should ensure through a properly monitored policy framework that water resources are not exploited by a particular sector or region at the expense of other regions in the country