Wirtschaftswissenschaftliche FakultätFrei zugängliche Publikationen aus der Wirtschaftswissenschaftlichen Fakultäthttps://www.repo.uni-hannover.de/handle/123456789/102024-03-19T13:41:18Z2024-03-19T13:41:18ZOpportunities to close wheat yield gaps in Nepal's Terai: Insights from field surveys, on-farm experiments, and simulation modelingDevkota, MinaDevkota, Krishna PrasadPaudel, Gokul PrasadKrupnik, Timothy J.McDonald, Andrew Jameshttps://www.repo.uni-hannover.de/handle/123456789/167212024-03-17T04:13:19Z2023-01-01T00:00:00ZOpportunities to close wheat yield gaps in Nepal's Terai: Insights from field surveys, on-farm experiments, and simulation modeling
Devkota, Mina; Devkota, Krishna Prasad; Paudel, Gokul Prasad; Krupnik, Timothy J.; McDonald, Andrew James
CONTEXT: Wheat (Triticum aestivum) is among the most important staple food crops in the lowland Terai region of Nepal. However, national production has not matched the increasing demand. From a South Asian regional perspective, average productivity is low with high spatial and temporal variability. OBJECTIVES: This study determines entry points for closing yield gaps using multiple diagnostic approaches, i.e., field surveys, on-farm experiments, and simulation models across different wheat production environments in the Terai region of Nepal. METHODOLOGY: Yield and production practice data were collected from 1745 wheat farmers' fields and analysed in tandem with over 100 on-farm experiments. These were complemented by long-term simulation modeling using the APSIM Next Generation to assess system production behavior over a range of climate years. RESULTS AND DISCUSSION: On-farm survey data suggests that yield and profit gaps under farmers' management (difference between the most productive (top 10th decile) and average wheat fields) were 1.60 t ha−1 and 348 USD ha−1 in the Terai region. The potential yield gap (difference between simulated potential yield and surveyed population mean) estimated was 4.63 t ha−1, suggesting ample room for growth even for the highest-yielding fields. Machine learning diagnostics of survey data, and on-farm trials identified nitrogen rate, irrigation management, terminal heat stress, use of improved varieties, seeding date, seeding method, and seeding rate as the principal agronomic drivers of wheat yield. While fields in the top 10th decile yield distribution had higher fertilizer use efficiencies and irrigation and seeding rates with similar overall production costs as average-yielding farmers. Our results suggest a complementary set of agronomic interventions to increase wheat productivity among lower-yielding farms in the Terai including advancing the time of seeding by 7–10 days on average, increasing nitrogen fertilizer by 20 kg ha−1, and alleviating water stress by applying two additional irrigations. SIGNIFICANCE: Although wheat yields in the Terai are among the lowest in the region, biophysical production potential is high and remains largely untapped due to sub-optimal agronomic management practices rather than intrinsic agroecological factors. Data from this study suggests that incremental changes in these practices may result in substantial gains in productivity and profitability.
2023-01-01T00:00:00ZIntegrated procurement and reprocessing planning for reusable medical devices with a limited shelf lifeRickers, SteffenSahling, Florianhttps://www.repo.uni-hannover.de/handle/123456789/166812024-03-15T02:00:20Z2024-01-01T00:00:00ZIntegrated procurement and reprocessing planning for reusable medical devices with a limited shelf life
Rickers, Steffen; Sahling, Florian
We present a new model formulation for a multiproduct dynamic order quantity problem with product returns and a reprocessing option. The optimization considers the limited shelf life of sterile medical devices as well as the capacity constraints of reprocessing and sterilization resources. The time-varying demand is known in advance and must be satisfied by purchasing new medical devices or by reprocessing used and expired devices. The objective is to determine a feasible procurement and reprocessing plan that minimizes the incurred costs. The problem is solved in a heuristic manner in two steps. First, we use a Dantzig-Wolfe reformulation of the underlying problem, and a column generation approach is applied to tighten the lower bound. In the next step, the obtained lower bound is transformed into a feasible solution using CPLEX. Our numerical results illustrate the high solution quality of this approach. The comparison with a simulation based on the first-come-first-served principle shows the advantage of integrated planning.
2024-01-01T00:00:00ZExploring the gap between research and practice in human resource management (HRM): a scoping review and agenda for future researchNegt, PhilipHaunschild, Axelhttps://www.repo.uni-hannover.de/handle/123456789/166392024-03-08T02:00:23Z2024-01-01T00:00:00ZExploring the gap between research and practice in human resource management (HRM): a scoping review and agenda for future research
Negt, Philip; Haunschild, Axel
The call for evidence-based decisions in HR has become a heated debate in recent years. An alleged research-practice gap has been identified by a number of HRM scholars, leading to recommendations for practice. To what extent the assumption of this gap is justified, theoretically or empirically, remains vague, however. Thus, building on a systematic literature search and the formulation of eligibility criteria for articles, we conducted a scoping review of the current research landscape. Our aim was to explore the constituent components, causes and consequences of the gap. Overall, it was found that research activity has so far been heterogeneous, a significant number of articles were conceptually driven, and a large proportion related to knowledge deficits of HR practitioners. A subset of consistent survey-based studies indicated little awareness of empirically supported practices in personnel selection. The qualitative, mixed-method, and content-analysis studies revealed other influences, such as research with limited practical relevance or divergent interests between scholars and practitioners (e.g., employee motivation). Based on the conceptual contributions, three thematic clusters were identified as causes for the gap: (1) communication barriers (e.g., insufficient interfaces), (2) methodological issues (e.g., rigor-relevance tensions), (3) accessibility, visibility, and dissemination of HR research (e.g., oversimplification of practical implications). There was a strong emphasis on presumed causes and their resolution, with less consideration given to the expected consequences of the gap (e.g., poorer organizational outcomes). Despite preliminary empirical indications for the existence of a research-practice gap in particular areas of HRM, many articles tend to focus on overarching recommendations for practice. We conclude that the HRM research-practice gap in itself has not yet been sufficiently empirically investigated. In view of this, we discuss implications and develop an agenda for future research.
2024-01-01T00:00:00ZLegal and Privacy Concerns of BYOD AdoptionDegirmenci, KenanBreitner, Michael H.Nolte, FerryPasslick, Jenshttps://www.repo.uni-hannover.de/handle/123456789/166012024-03-05T02:00:18Z2023-01-01T00:00:00ZLegal and Privacy Concerns of BYOD Adoption
Degirmenci, Kenan; Breitner, Michael H.; Nolte, Ferry; Passlick, Jens
We investigate legal concerns in privacy calculus, which are currently not given enough attention in privacy research. Legal aspects can lead to liability issues in various information systems scenarios such as bring your own device (BYOD) in the workplace. To analyze the impact of legal concerns in privacy calculus, we conducted a quantitative study by surveying 542 employees from three countries: United States, Germany, and South Korea. Building on our research model to test our hypothesized relationships, structural equation modeling was employed. Our findings provide recommendations for multinational organizations to mitigate legal concerns in privacy calculus. A comparison of the three countries reveals that employees from the United States and South Korea place greater emphasis on legal concerns compared to German employees. We develop an understanding of employees’ concerns with liability issues, and how these affect their privacy calculus in a BYOD context.
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