Gems: Objects of aesthetic beauty and scientific curiosity

This article does not have an abstract

Heats of Formation of Solid Solutions of CsCl with CsBr

1008-100

Robust scheduling practices in the U.S. airline industry: Costs, returns, and inefficiencies

Airlines use robust scheduling to mitigate the impact of unforeseeable disruptions on profits. We examine how effectively three common practices—flexibility to swap aircraft, flexibility to reassign gates, and scheduled aircraft downtime—accomplish this goal. We first estimate a multiple-input, multiple-outcome production frontier, which defines the attainable set of outcomes from given inputs. We then recover unobserved input costs and calculate how expenditure on inputs affects outcomes and revenues. We find that the per-dollar return from expenditure on gates, or more effective management of existing gate capacity, is three times larger than the per-dollar returns from other inputs. Next, we use the estimated trade-offs faced by carriers along the frontier to measure the value to carriers of reducing delays. Finally, we calculate the improvement in carriers’ outcomes and profits if their operational inefficiencies are eliminated. On average, we estimate that operational inefficiencies cost carriers about $1.7 billion in revenue annually

Some illustrations of the optical behaviour of iridescent calcite

The paper reproduces illustrations of various optical effects displayed by twinning layers in iridescent calcite. Brief descriptive notes are appended

Convective phenomena near a heated surface

This article does not have an abstract

Thermo-optic behaviour of silicon carbide

This article does not have an abstract

The infra-red absorption spectrum of potassium chlorate crystals: Part I

The infra-red transmission through the 001 face of a single crystal of potassium chlorate reveals, besides a broad absorption band in the range 9·2 μ to 12 μ , a second and narrower band with its maximum at 5·3 μ . The former band can be explained as due to the infra-red activity of the vibration frequencies ν1 (930 cm.-1) and ν2 (975 cm.-1) of the crystal also observed in the Raman effect, and their combinations with the low frequency lattice oscillations. The band at 5·3 μ may likewise be explained as due to the infra-red activity of the octaves of ν1 and ν2 and of their summational frequency

Timely After-Sales Service and Technology Adoption: Evidence from the Off-Grid Solar Market in Uganda

Problem definition: Adoption and continued use of novel technologies has the potential to significantly accelerate social and economic development in emerging markets. In this paper, we examine to what extent timely after-sales service i.e., faster resolution of repair tasks impacts technology adoption. In particular, we empirically assess the impact of service wait times on the adoption of solar home systems by first-time users (i.e., adopters of the technology) in off-grid Uganda. Academic / Practical Relevance: Our study sheds light on a previously understudied driver of technology adoption - customers' post-purchase experience related to after-sales service. We also provide evidence on how negative word-of-mouth stemming from long service wait times hampers customer acquisition. Methodology: We address our research question using detailed customer-level sales and service data from a leading assembler and distributor of solar home systems in Uganda. We develop a fixed effects base specification and two instrumental variables specifications that leverage different sources of exogenous geo-spatial variation - in service task locations, weather and road quality. Results: We find that timely after-sales service experienced by existing customers is a strong driver of adoption by first-time users. A one week increase in average wait time for service decreases adoption by up to 32.4%. The relationship between wait times and adoptions is heterogeneous and depends on the types of pending service cases. We also find that the number of customers acquired through referrals from an existing customer depends on the referring customer's service wait time. This provides evidence of a strong word-of-mouth channel of information sharing. Managerial Implications: Our findings have direct implications for the customer acquisition strategies of technology firms and for technology investors in emerging markets. Our results are also relevant for policy makers who aim to harness technology to improve the socio-economic lives of people living in these regions. Importantly, we provide empirical evidence of a direct link between after-sales service and technology adoption, which is of relevance to managers outside of emerging markets as well

Man on a mission for waste to wealth transformation

Shri. Ramdas Tukaram Kokare, presently working as Chief Officer in Municipal Corporation, Karjat which has a total population of 30,000 and generates Class III Municipal Solid Waste (MSW) in the tune of 12 metric tonnes per day. Earlier during 2010 to 2015 he had served as Chief Officer at Municipal Corporation Dapoli, Maharashtra and during 2015-2017 he at Vengurla also in Maharashtra. In 2010, Shri Ramdas came up with the idea of waste management at the source level and decided to segregate plastic waste into recyclable and non-recyclable categories. Plastic carry bags of less than 50 micron thickness were in the non-recyclable category, while bottles, packaging material of food items and wrappers were to be recycled for further usage. Local self-help groups were roped in to produce paper bags and some awareness campaigns were organized