Abstract This study investigated the effect of turbulence on the nonlinear vibration of a symmetrical rigid rotor supported by two identical journal bearings. The bearings consisted of various length to diameter (L/D) ratio circular and 2-lobe bearings with differing pad preloads. Two turbulent (Ng–Pan–Elrod and Constantinescu model) and one laminar Reynolds equations were selected for comparison, and they were solved using a finite difference method to obtain nonlinear bearing forces. The nonlinear equations of motion for the rotor-bearing system were solved using a shooting method and arclength continuation to obtain limit cycles for each bearing configuration. Floquet multiplier analysis was then utilized to identify the stability of the obtained limit cycles. For the cases of the circular and 2-lobe bearing without pad preload, the turbulent Reynolds equations yielded a lower onset speed of instability and L/D ratio at which the bifurcation type changed from supercritical to subcritical than the laminar Reynolds equation. However, at higher pad preloads (preloads of 0.25 or 0.5), the turbulence effects increased the onset speed of instability, especially for L/D ratios > 0.7, and only supercritical bifurcation was observed. For all bearing configurations, the ratio of the limit cycle whirl frequency to shaft rotational speed for both turbulence bearing models was higher than that of the laminar bearing model, and the Ng–Pan–Elrod turbulence model always generated lower onset speed of instability than the Constantinescu model.

ABSTRACTA very high jobless people in the city has created an informal sector. This informal sector has become an alternative way for them to find a job. It has happened since it is very relatively easy joining or leaving this informal sector as there is not any particular regulation required. This research aims to study the contribution of street stalls upon the multiplier output, revenue, employment and forward-backward linkage over the economy. Method of analysis has been using input-output analysis and the research location has taken place in Bogor. The result of the research has indicated that the availability of the street stalls in the city cannot be considered as a marginal sector as they have been contributing positively the city economy either in the multiplier analysis or forward-backward linkage. Organizing and registering the street stalls in Bogor should have to be executed properly and periodically in order to find out their economical potential, making sure that they will not jeopardize the landscape of public facility. However, a particular association should have to be established in order to ease the supervision of the street stalls and to improve their quality accordingly.Keyword : Street stalls, informal sector, output, revenue, manpowerABSTRAKTingginya tingkat pengangguran perkotaan menumbuhkan sektor informal. Pedagang kaki lima merupakan salah satu sektor informal menjadi alternatif bagi mereka yang tidak mendapatkan pekerjaan disebabkan mudahnya untuk masuk dan keluar di sektor informal relatif mudah karena tidak ada aturan secara khusus yang mensyaratkan. Penelitian ini bertujuan untuk mengetahui kontribusi pedagang kaki lima terhadap multiplier output, pendapatan, penyerapan tenaga kerja dan forward-backward linkage terhadap perekonomian. Metode analisis yang digunakan adalah analisis input-output dan lokasi penelitian di Kota Bogor. Hasil penelitian menunjukan keberadaan pedagang kaki lima perkotaan tidak dapat dipandang sebagai sektor yang marginal, pedagang kaki lima memberikan kontribusi positif terhadap perekonomian perkotaan baik dalam analisis multiplier dan analisis forward-backward linkage. Penataan dan pendataan pedagang kaki lima di Kota Bogor perlu dilakukan secara periodik agar dapat diketahui potensi ekonomi, tidak mengganggu landscap dan peruntukan fasilitas umum kota. Perlunya pembentukan assosiasi agar dapat lebih mudah dalam pengawasan dan upaya peningkatan kualitas pedagang kaki lima.Kata Kunci : Pedagang Kaki Lima, Sektor Informal, Output, Pendapatan, Tenaga Kerja

Kenya ranks among the countries with the highest micronutrient deficiency worldwide. Due to their high micronutrient content, African indigenous vegetables (AIVs) can be a solution to this problem, and urban areas in Kenya have seen a rise in demand for these crops in the previous decade. To fill the gap between supply and demand, programmes to promote AIV production have been implemented in rural and peri-urban areas. However, the effects of increased AIV production on income and food security in the regional economies are not clear. Thus, in this analysis, we first evaluate differences between the livelihoods of household groups with different levels of food security in rural and peri-urban Kenya using a two-step cluster analysis. Then, we generate a regional social accounting matrix (SAM) and calculate the direct and indirect income effects of AIVs and other crops grown in the area using a multiplier analysis. For the analysis, a total of 706 small-scale vegetable producers in four counties in Kenya were interviewed in 2015. Households in rural areas were more food insecure, especially with respect to the utilization and stability dimension of food security. Multiplier analysis showed increased indirect income effects of AIVs in the regional economy compared to those of many cash crops. We suggest further promoting the production of AIVs in rural and peri-urban Kenya.

The manufacturing industry sector is an economic sector that provides the largest contribution to the national economy so that the performance of the manufacturing industry greatly affects overall economic performance. Industrial sector investment is currently required to be located within industrial estates in order to improve efficiency, organize space, manage the environment and optimize the multiplier effects on other economic sectors. This study aims to analyze the multiplier effects of increased investment in the manufacturing industry sector in industrial estate on the performance of the transport/logistics sector. The analysis model uses the Social Accounting Matrix (SAM) Model, which is an effect multiplier analysis. The results of the research show that the increase in investment in the manufacturing industry sector located in the industrial area provides a multiplier effect on improving the performance of the transportation/logistics sector in the form of increased transportation/logistics sector revenues.

ABSTRACT                                                       South Lampung regency as one of the gates of Sumatra Island became one of the many tourist destinations in Indonesia, especially on the island of Sumatra. The existence of tourism activities in South Lampung District economic impacts for the community, such as increasing public income, increased employment and business opportunities for local communities. The purpose of this research is to measure the economic impact of tourism activities in South Lampung Regency. In analyzing the economic impacts of tourism activities in South Lampung District using Keynesian Income Multiplier and multiplier analysis to see the direct impact, indirect impacts, and further impacts. Based on the results of the analysis shows that the presence of tourism activities in South Lampung Regency has had an economic impact on the local economy even though the perceived impact is still small. As evidenced by the value of Keynesian Income Multiplier is 1.95, value ratio Income Multiplier of Type I 1.09, and value ratio Income Multiplier of Type II 1.34. Keywords: South Lampung Regency, Economic Impact, Tourism Activities, Multiplier Effects

The effect of 2 lobes journal bearing parameters such as L/D ratio and pad preload on the bifurcation of the rigid rotor is investigated in comparison with the circular bearing. Nonlinear bearing force in the equation of motion is obtained by solving Reynolds equation using the finite difference method. Shooting method and Floquet multiplier analysis are employed to obtain limit cycles and their stability. The results show that, for some bearing parameters, multiple limit cycles coexist at a specific shaft rotational speed range. Comparing with the circular bearing of same L/D ratio, the 2 lobes bearing without pad preload decreases the onset speed of instability and also decreases speed range from the onset speed of instability (Hopf) point to the limit point of the bifurcation (saddle-node) in the subcritical bifurcation case. Increasing the pad preload only increases the onset speed of instability significantly in the small L/D ratio case. For both circular and 2 lobes bearing, increasing the L/D ratio decreases the onset speed of instability and tends to change the type of the bifurcation from supercritical to subcritical.

Kalimantan Barat is a province which has the highest poverty rates among other provinces in Kalimantan. Sector’s output growth of the economy affects the redistribution of income and poverty reduction. Increased economic sector output reduce poverty through the distribution of income . Sector development policy needed to boost the economy and poverty alleviation. This study aimed to analyze the relationship between sector’s output growth of the economy and poverty reduction using Input-Output Miyazawa and decomposition of FGT (Foster-Greer-Thorbecke) poverty index. Agricultural sector has an important role in output growth, employment, and household income distribution.The decomposition method showes that direct effect of growth in manufacture alleviates poverty among poor households, and total effect of growth in agricultural sectors(food crops and estate crops) alleviates poverty among poor households in Kalimantan Barat. The main policy implication is agricultural industrialization and human capital of the poor needs to be enhanced by education and training if they are not to be sealed off the industrialization process.Keywords: I-O Miyazawa, Poverty, Multiplier Analysis

Kalimantan Barat is a province which has the highest poverty rates among other provinces in Kalimantan. Sector’s output growth of the economy affects the redistribution of income and poverty reduction. Increased economic sector output reduce poverty through the distribution of income . Sector development policy needed to boost the economy and poverty alleviation. This study aimed to analyze the relationship between sector’s output growth of the economy and poverty reduction using Input-Output Miyazawa and decomposition of FGT (Foster-Greer-Thorbecke) poverty index. Agricultural sector has an important role in output growth, employment, and household income distribution.The decomposition method showes that direct effect of growth in manufacture alleviates poverty among poor households, and total effect of growth in agricultural sectors(food crops and estate crops) alleviates poverty among poor households in Kalimantan Barat. The main policy implication is agricultural industrialization and human capital of the poor needs to be enhanced by education and training if they are not to be sealed off the industrialization process.Keywords: I-O Miyazawa, Poverty, Multiplier Analysis