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This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69˚N, Longitude 86.73˚E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R 2 ) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available.

Kathmandu Metropolitan City has attempted to reorganize its solid waste management a number of times. The German Technical and Financial Aid Organization led early efforts that were followed by a number of more recent experiments that left the city with an unsustainable solid waste management system following the termination of foreign aid. To examine this failure, the research team evaluated household surveys, field observations, interviews, and other primary and secondary information within the context of technical, social, and institutional analyses. The survey results show that the solid waste collection rates are far below the 90% claimed by the metropolis and street sweeping consumes approximately 51% of its solid waste budget. As a result of the relatively low collection rates the city residents are encouraged to dump waste into public lands. Consequently, too much of the city's resources are focused on sweeping rather than collection. Kathmandu needs to recognize informal waste picking, privatize, use local techniques, build capacity, promote bottom-up and participatory styles of management, and regulate policies to maintain solid waste management.

This study presents the spectral monthly and seasonal variation of aerosol optical depth (τAOD), single scattering albedo (SSA), and aerosol absorption optical depth (AAOD) between 2010 and 2018 obtained from the Aerosol Robotic Network (AERONET) over Pokhara, Nepal. The analysis of these column-integrated aerosol optical data suggests significant monthly and seasonal variability of aerosol physical and optical properties. The pre-monsoon season (March to May) has the highest observed τAOD(0.75 ± 0.15), followed by winter (December to February, 0.47 ± 0.12), post-monsoon (October and November, 0.39 ± 0.08), and monsoon seasons (June to September, 0.27 ± 0.13), indicating seasonal aerosol loading over Pokhara. The variability of Ångström parameters, α, and β, were computed from the linear fit line in the logarithmic scale of spectral τAOD, and used to analyze the aerosol physical characteristics such as particle size and aerosol loading. The curvature of spectral τAOD, α’, computed from the second-order polynomial fit, reveals the domination by fine mode aerosol particles in the post-monsoon and winter seasons, with coarse mode dominating in monsoon, and both modes contributing in the pre-monsoon. Analysis of air mass back trajectories and observation of fire spots along with aerosol optical data and aerosol size spectra suggest the presence of mixed types of transboundary aerosols, such as biomass, urban-industrial, and dust aerosols in the atmospheric column over Pokhara.

The global solar radiation (GSR) and cloud transmittance factor (cf) are measured at the horizontal surface since 2009 using calibrated CMP6 Pyranometer and NILUUV Irradiance Meter at Pokhara (28.22°N, 83.32°E) which is about 800m from the sea level lying just 20km south of the Himalayas. This paper explains the daily, monthly and seasonal variation of global solar radiation and also compared with temperature and rainfall to global solar radiation. The annual average daily global solar radiation is about 4.81 kWh/m 2 /day which is sufficient to promote solar active and passive solar energy technology at sub-Himalaya terrain Pokhara and other similar geographical locations. The correlation coefficient 0.70 is found in between clearness index (K) and cloud transmittance factor (cf). This novel result can be used for location of similar meteorological and geographical characteristics at which solar data are not available.

The daily aerosol optical depth (AOD) data are derived from AERONET over Bode, Bhaktapur (27.68° N, 85.39° E, 1297 m above sea level) for a period of one year 2013. Annual mean of Atmospheric turbidity factors are calculated. The effect of different physical as well as meteorological parameters on the Linke turbidity factor was analyzed. The yearly mean of solar insolation, Angstrom exponential (α),Angstrom coefficient of turbidity (β) and Linke turbidity (LT) were found 4.70 ± 1.10kWh/m2/day, 1.13 ± 0.21 ,0.18 ± 0.14 and 5.70 ± 2.46 respectively. Annual average of visibility is 2.98 ± 2.13 km. Result of this research work is beneficial for the further identification, impact and analysis of atmospheric turbidity at different places.

This research work purpose to estimate the daily global solar radiation (GSR) using CMP6 pyranometer at low altitude of Simara Airport (lat. 27°9’33” N and long. 84°58’48” E, Alt.137m respectively). The measured data is used to study the diurnal, monthly, and seasonal variation of GSR. The maximum and minimum value of GSR is found at the spring and winter season respectively. A number of multi linear regression equations were developed to predict the relationship between GSR with one or more combinations of meteorological parameters using the regression technique and calculate the empirical constants from Tiwari & Sangeeta model which is the best empirical model among other tested models. The empirical constants and sunshine hour are utilized to estimate the GSR for the years 2009 and 2010 in the Simara Airport. The annual average solar insolation 4.62 and 4.56 k/m2/day is found at Simara Airport for years 2009 and 2010. The performance of each model was analyzed by calculating Root Mean Square Error (RMSE), Coefficient of Determination (R2) Mean Bias Error (MBE), and Mean Percent Error (MPE). The finding empirical constants 0.30 and 0.52 can be utilized to estimate the GSR where there is no measured data of GSR at similar meteorological sites of Nepal.Journal of the Institute of Engineering, 2018, 14(1): 143-150

In this paper, a newly proposed surface ropeway named "Circulating Cable Supported up down Walking Technology by Using Gravity" (CASWAT-G) is presented. CASWAT-G is facilitated by the gravitational force of the descending person, functioning as a gravitational energy harvester. At gravity balance, the ascending and descending persons apply very mild leg muscle forces for easy upwards and downwards walking while using it. Its working principle is close to the one of funicular and ski lift systems. Its working principles with the respective theory are presented to explain the way CASWAT-G functions. Experimental model data showed that a significant amount of harvested gravitational force from the descending person was utilized by the ascending person. The efficiency of the system was found to be above 80%, meaning that its performance is good enough to be used as a transportation facility in mountainous areas of developing countries, like Nepal. It could help not only to protect the environment and save energy but also to promote the livelihood and sustainable development of developing countries, especially in mountainous areas. In addition, it can be used to supply daily required goods to these areas and to promote local products and tourism.