An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran＇s Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree...An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran＇s Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree processing starts when the felling season ends. We identified the elements of felling and processing work phases, and 142 cycles and 110 cycles were respectively recorded for felling and processing. On the basis of data analysis （time study）, we developed statistical models of effective time consumption in the respective work phase and for its total productivity. The production rate of felling with and without delay time was 9.7 and 11.65 trees per hour （0.17 USD.m^-3 and 0.21 USD-m^-3）, and the average production cost with and without delay was 1.21 USD and 1.45 USD per tree, respectively. The average productivity of processing was 35 m^3 per effective hour and the average unit cost of processing was 0.92 USD.m^-3.展开更多
Objective: To examine the prognostic factors of progression from HIV to AIDS and AIDS to the death in people living with HIV/AIDS in Iran.Methods: In this registry-based retrospective cohort study, we recruited 28 873...Objective: To examine the prognostic factors of progression from HIV to AIDS and AIDS to the death in people living with HIV/AIDS in Iran.Methods: In this registry-based retrospective cohort study, we recruited 28 873 HIV-infected people from 158 Behavioral Diseases Counseling Centers of Iran.Two outcomes of interest included survival rates from HIV diagnosis to AIDS and from AIDS to the death.We used Kaplan-Meier and Cox regression model to investigate survival rate and factors affecting on survival controlling effect of confounding factors.Results: The one, three, five, and ten-year survival rate from HIV to AIDS were 85%, 73%, 61% and 32%, and for AIDS to death were 90%, 81%, 74% and 55%, respectively.Multivariate Cox regression analysis indicated that the risk of progression from AIDS phase toward death in individuals with CD4 less than 200/mm^3, infected with tuberculosis(TB) and not treated by antiretroviral therapy(ART) was 2.17(95% CI: 1.62-2.90), 1.49(95% CI: 1.01-2.20) and 4.88(95% CI: 3.42-6.96) times higher respectively.The risk of progression to AIDS in patients with baseline CD4 less than 200/mm^3 was 2.32(95% CI: 2.14, 2.51) times higher than patients with CD4 > 200/mm^3(P=0.001).On the other hand, tuberculosis increases the risk of death by 49.0%(P=0.04).The hazard ratio of death in patients who did not receive ART was 4.88(95% CI: 3.42, 6.96) times higher than patients who received ART(P<0.001).Conclusion: The early detection of HIV, the screening and treatment of TB and receiving the ART improve the survival of HIV/AIDS patients significantly, and prevent the transmission of HIV to other people.展开更多
Introduction: Nursing is the largest healthcare profession in Malawi with more than 11,000 registered nurses (RNs), nurse technicians and midwives (NTM) practicing in hospitals and other settings like nursing colleges...Introduction: Nursing is the largest healthcare profession in Malawi with more than 11,000 registered nurses (RNs), nurse technicians and midwives (NTM) practicing in hospitals and other settings like nursing colleges nationwide. Student preparation is mostly done by nursing tutors in all the nursing colleges using numerous types of teaching aids. Methods: Descriptive exploratory design which utilized both qualitative and sequential quantitative methods was applied to Iterated Purposive Probability Sampling (IPPS) of 10 nursing colleges in Malawi. This was done to 129 students and 82 nurse tutors in two structured questionnaires, 40 nurse tutors in-depth interviews and 10 students focus groups. There were 32 variables for the teaching aids under five ranked Likert scale and the Cronbach’s Alpha was found to be 0.932 without standardisation and it was 0.952 after standard-disation. Results: Although nurse tutors show that they use manikins to teach (0.011 < p = 0.05), students seem not to agree on the utilization of the manikins during teaching both in class and at the clinical area (0.05;p = 0.05). There is also increased discrepancy between students and nurse tutors on internet utilization as the teaching aid as the Beta Coefficient value was (B = 0.202) for the nurse tutors and (B = 1.061) for the students basing on their experience. Use of patient as a teaching aid is very common in Malawi and both the nurse tutors and students agree that it is the realistic and best way in teaching and has a strong binary logistic regression with a model outcome of (OR = 1.431;95%CI (0.890 ± 2.304);p = 0.139). Conclusion: There is a need to develop the teaching strategies that would be conducive with the current scarcity of the teaching aids. Use of patients if ethically followed remains the most effective and efficient teaching aid in developing countries.展开更多
Based on a simulation model of a semiconductor manufacturer, operator-machine ratio （OMR） analysis is made using work study and time study. Through sensitivity analysis, it is found that labor utilization decreases ...Based on a simulation model of a semiconductor manufacturer, operator-machine ratio （OMR） analysis is made using work study and time study. Through sensitivity analysis, it is found that labor utilization decreases with the increase of lot size. Meanwhile, it is able to identify that the OMR for this company should be improved from 1 ： 3 to 1 ： 5. An application result shows that the proposed model can effectively improve the OMR by 33%.展开更多
基金financially supported by Iranian Ministry of Science, Research and Technologies and University of Joensuu
文摘An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran＇s Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree processing starts when the felling season ends. We identified the elements of felling and processing work phases, and 142 cycles and 110 cycles were respectively recorded for felling and processing. On the basis of data analysis （time study）, we developed statistical models of effective time consumption in the respective work phase and for its total productivity. The production rate of felling with and without delay time was 9.7 and 11.65 trees per hour （0.17 USD.m^-3 and 0.21 USD-m^-3）, and the average production cost with and without delay was 1.21 USD and 1.45 USD per tree, respectively. The average productivity of processing was 35 m^3 per effective hour and the average unit cost of processing was 0.92 USD.m^-3.
基金The study funded by the Vice-chancellor for Research and Technology,Hamadan University of Medical Sciences(No.9508044500)
文摘Objective: To examine the prognostic factors of progression from HIV to AIDS and AIDS to the death in people living with HIV/AIDS in Iran.Methods: In this registry-based retrospective cohort study, we recruited 28 873 HIV-infected people from 158 Behavioral Diseases Counseling Centers of Iran.Two outcomes of interest included survival rates from HIV diagnosis to AIDS and from AIDS to the death.We used Kaplan-Meier and Cox regression model to investigate survival rate and factors affecting on survival controlling effect of confounding factors.Results: The one, three, five, and ten-year survival rate from HIV to AIDS were 85%, 73%, 61% and 32%, and for AIDS to death were 90%, 81%, 74% and 55%, respectively.Multivariate Cox regression analysis indicated that the risk of progression from AIDS phase toward death in individuals with CD4 less than 200/mm^3, infected with tuberculosis(TB) and not treated by antiretroviral therapy(ART) was 2.17(95% CI: 1.62-2.90), 1.49(95% CI: 1.01-2.20) and 4.88(95% CI: 3.42-6.96) times higher respectively.The risk of progression to AIDS in patients with baseline CD4 less than 200/mm^3 was 2.32(95% CI: 2.14, 2.51) times higher than patients with CD4 > 200/mm^3(P=0.001).On the other hand, tuberculosis increases the risk of death by 49.0%(P=0.04).The hazard ratio of death in patients who did not receive ART was 4.88(95% CI: 3.42, 6.96) times higher than patients who received ART(P<0.001).Conclusion: The early detection of HIV, the screening and treatment of TB and receiving the ART improve the survival of HIV/AIDS patients significantly, and prevent the transmission of HIV to other people.
文摘Introduction: Nursing is the largest healthcare profession in Malawi with more than 11,000 registered nurses (RNs), nurse technicians and midwives (NTM) practicing in hospitals and other settings like nursing colleges nationwide. Student preparation is mostly done by nursing tutors in all the nursing colleges using numerous types of teaching aids. Methods: Descriptive exploratory design which utilized both qualitative and sequential quantitative methods was applied to Iterated Purposive Probability Sampling (IPPS) of 10 nursing colleges in Malawi. This was done to 129 students and 82 nurse tutors in two structured questionnaires, 40 nurse tutors in-depth interviews and 10 students focus groups. There were 32 variables for the teaching aids under five ranked Likert scale and the Cronbach’s Alpha was found to be 0.932 without standardisation and it was 0.952 after standard-disation. Results: Although nurse tutors show that they use manikins to teach (0.011 < p = 0.05), students seem not to agree on the utilization of the manikins during teaching both in class and at the clinical area (0.05;p = 0.05). There is also increased discrepancy between students and nurse tutors on internet utilization as the teaching aid as the Beta Coefficient value was (B = 0.202) for the nurse tutors and (B = 1.061) for the students basing on their experience. Use of patient as a teaching aid is very common in Malawi and both the nurse tutors and students agree that it is the realistic and best way in teaching and has a strong binary logistic regression with a model outcome of (OR = 1.431;95%CI (0.890 ± 2.304);p = 0.139). Conclusion: There is a need to develop the teaching strategies that would be conducive with the current scarcity of the teaching aids. Use of patients if ethically followed remains the most effective and efficient teaching aid in developing countries.
文摘Based on a simulation model of a semiconductor manufacturer, operator-machine ratio （OMR） analysis is made using work study and time study. Through sensitivity analysis, it is found that labor utilization decreases with the increase of lot size. Meanwhile, it is able to identify that the OMR for this company should be improved from 1 ： 3 to 1 ： 5. An application result shows that the proposed model can effectively improve the OMR by 33%.
