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The purpose of this paper is to design free return trajectories launching at lower-latitude launch site Wenchang and landing at relatively high-latitude landing site Siziwang Banner tailored to human lunar missions for China, and in general demonstrate the feasibility of high-latitude landings with acceptable entry range.

Free return trajectories satisfying all basic constraints were generated directly by a high-fidelity model with multiple differential corrections. Suitable initial assumptions, control parameters, constraints and stopping conditions were set. Method was developed to automatically converge unlimited trajectories accurately to the same constraints, and their characteristics affected by the ephemeris were analyzed.

Launching into lower Earth inclination plus high-latitude landing with acceptable entry range requires asymmetric trajectories with high inclination Earth entry only from the south. Periodic trends of parameters at launch, injection and entry were found and analyzed. Nominal trajectory covering phases from launch to landing for China human moon flight with minimum entry range were designed.

Such trajectories can be used by China’s future manned lunar missions. Spacecraft capability and ground station distribution shall adjust accordingly.

Previous studies mainly concentrated on symmetric free returns using low-fidelity models first. This paper investigates asymmetric free returns skipping simplified gravity model approximation to simultaneously achieve high-latitude landing and acceptable entry range, and accurate automated generation of feasible trajectories daily across 19-year lunar nodal cycle within every monthly launch window without trial and error to reflect the actual effect by the ephemeris only. Others include landing accurately by controlling entry direction and range (and altitude), minimizing entry range and designing an effective scheme of differential correction for full convergence.

The purpose of this paper is to establish an orbital launch window for manned Moon‐to‐Earth trajectories to support China's manned lunar landing mission requirements of high‐latitude landing and anytime return, i.e. the capability of safely returning the crew exploration vehicle at any time from any lunar parking orbit. The launch window is a certain time interval during which the transearth injection may occur and result in a safe lunar return to the specified landing site on the surface of the Earth.

Using the patched conic technique, an analytical design method for determining the transearth trajectories is developed with a finite sphere of influence model. An orbital launch window has been established to study the mission sensitivities to transearth trip time and energy requirements. The results presented here are limited to a single impulsive maneuver.

The difference between the results of the analytical model and high‐fidelity model is compared. This difference is relatively small and can be easily eliminated by a simple differential correction procedure. The launch window duration varies with launch date, from less than one hour to greater than 20 h, and the launch window occurs every day in the sidereal month.

The solution can be used to serve as an initial estimate for future optimization procedures.

The orbital launch window can be used to provide the basis for the preparation of an orbital launch timetable compatible with lunar missions and re‐entry conditions requirements.

Previous studies were mainly concentrated on the launch windows for the departure from the Earth. This paper investigates and establishes the orbital launch window for Moon‐to‐Earth trajectories.

The purpose of this paper is to identify and analyze the link between climate change and agricultural growth in Malaysia, and pursue three sub‐objectives: to determine and analyze the link between agricultural growth rate and climate change score; to determine and analyze the link between per capita CO₂ emissions and agricultural production index; and to determine and analyze the link between per capita agricultural production index and per capita CO₂ emissions.

Relevant time series data compiled from several online sources including the Germanwatch, Ministry of Finance, Malaysia, and the United Nations database were used. The data for agricultural growth rate and climate change score for Malaysia were found to be available only for the four recent years from 2006 to 2009. The data for other variables such as per capita agricultural production index and per capita CO₂ emissions have been standardized covering the period from 1990 to 2004. The ordinary least squares methods were employed to estimate the parameters in the three linear regression models.

The empirical results of the study reveal three important observations for Malaysia: the link between agricultural growth rate and climate change score is proven to be negative, but insignificant (p>0.1); the link between per capita CO₂ emissions and agricultural production index is found to be direct and highly significant (p<0.01); and the link between per capita agricultural production index and per capita CO₂ emissions is proven to be positive and highly significant (p<0.01). Also, an increasing level of per capita CO₂ emissions in the country is proven to have both detrimental and beneficial effects on its agricultural growth. For instance, agricultural growth in Malaysia is found to produce significant effects on climate change, primarily through the production and release of CO₂.

The paper recommends that the two‐way link between climate change and agricultural growth depends on the balance of the effects and that an in‐depth assessment of such effects might help the appropriate authority to anticipate the effects more accurately. The paper will be useful to researchers wishing to conduct research and develop models on the nexus between climate change and agriculture.

The key purpose of this paper is to examine the causality and long‐run relationship between CO2 emission and agricultural output for an agriculture‐dependent developing country, namely Bangladesh.

In order to attain the objective, this study has used long‐time series data and employed advanced econometric techniques of unit root test, nonlinear least square estimation, Vector Error Correction estimation and Granger causality test.

The empirical results of the study reveal that Bangladesh agricultural output is not a Granger causal for Bangladesh CO2 emission, but the country's CO2 emission is a Granger causal for its agricultural output. The results also reveal for Bangladesh that any disequilibrium between CO2 emissions and agricultural output could take approximately 17 years to converge to the long‐run equilibrium. The results further reveal that the adjustment rate for Bangladesh agricultural output is positive and quite fast at the rate of 69 percent a year. So any disequilibrium will be corrected mostly by the adjustment in Bangladesh agricultural output.

The current CO2 emission in Bangladesh is still below the equilibrium level, which is considered to be an advantage for the country, particularly its agriculture sector which will reasonably not face any stricter CO2 emissions controlling policies and regulations in the near future.

The originality of this study lies on the extent to which an agriculture‐dependent developing country such as Bangladesh does not have greater concern about the CO2 emission for now and the near future. The originality does also lie on the fact that no other study has yet examined this issue.

The purpose of this paper is to test the impact of the soybean rejuvenation plan and the subsidy on farmers' land allocation decisions, which may reference policy adjustment from a micro perspective.

The paper develops a multi-objective optimized programming model on farm-level, which simulated the land-use changes, as well as the resulting changes in benefits of the rational “typical farm”. The simulation scenarios include changes in subsidy policy and production efficiency, and the baseline scenario was the production status in 2018.

The results show that an increase in soybean producer subsidy will encourage farmers to allocate more land for soybean planting, which can be considered as a policy tool in promoting soybean production in China. Besides, the effect of subsidy in adjusting soybean acreage for farms is further affected by external conditions such as production technology (such as breeding technology, pesticide and fertilizer application efficiency). Meanwhile, large-scale farms show more significant land adjustments when facing changes in policies and external conditions.

The value of this paper is to simulate the effects of soybean policy and subsidy change on farmers' land-allocation decisions through a multi-objective farmer decision-making model, which provides a micro perspective to understand the implementation effect of the soybean revitalization plan.

Fewer researchers have investigated the climatic and economic drivers of land-use change simultaneously and the interplay between drivers. This paper aims to investigate the nonlinear and interaction effects of price and climate variables on the rice acreage in high-latitude regions of China.

This study applies a multivariate adaptive regression spline to characterize the effects of price and climate expectations on rice acreage in high-latitude regions of China from 1992 to 2017. Then, yield expectation is added into the model to investigate the mechanism of climate effects on rice area allocation.

The results of importance assessment suggest that rice price, climate and total agricultural area play an important role in rice area allocation, and the importance of temperature is always higher than that of precipitation, especially for minimum temperature. Based on the estimated hinge functions and coefficients, it is found that total agricultural area has strong nonlinear and interaction effects with climate and price as forms of third-order interaction. However, the order of interaction terms reduces to second order after absorbing the expected yield. Additionally, the marginal effects of driven factors are calculated at different quantiles. The total area shows a positive and increasing marginal effect with the increase of total area. But the positive impact of price on the rice area can only be observed when price reached 50% or higher quantiles. Climate variables also show strong nonlinear marginal effects, and most climatic effects would disappear or be weakened once absorbing the expected rice yield. Expected yield is an efficient mechanism to explain the correlation between crop area and climate variables, but the impact of minimum temperature cannot be completely modeled by the yield expectation.

To the best of the authors’ knowledge, this is the first study to examine the nonlinear response of land-use change to climate and economic in high-latitude regions of China using the machine learning method.

Three Coupled Model Intercomparison Project Phase 5 models involved in the G4 experiment of the Geoengineering Model Inter-comparison Project (GeoMIP) project were used to investigate the impact of stratospheric aerosol injection (SAI) on the mean surface air temperature and precipitation extremes in Africa.

This impact was examined under G4 and Representative Concentration Pathway (RCP) 4.5 scenarios on the total precipitation, the number of rainy days (RR1) and of days with heavy rainfall (R20 mm), the rainfall intensity (SDII), the maximum length of consecutive wet (CWD) and dry (CDD) days and on the maximum rainfall in five consecutive days (Rx5day) across four regions: Western Africa (WAF), Eastern Africa (EAF), Northern Africa and Southern Africa (SAF).

During the 50 years (2020–2069) of SAI, mean continental warming is −0.40°C lower in G4 than under RCP4.5. During the post-injection period (2070–2090), the temperature continues to increase, but at a lower rate (−0.19°C) than in RCP4.5. During SAI, annual rainfall in G4 is significantly greater than in RCP4.5 over the high latitudes (especially over SAF) and lower over the tropics. The termination of SAI leads to a significant increase of rainfall over Sahel and EAF and a decrease over SAF and Guinea Coast (WAF).

Compared to RCP4.5, SAI will contribute to reducing significantly regional warming but with a significant decrease of rainfall in the tropics where rainfed agriculture account for a large part of the economies. After the SAI period, the risk of drought over the extratropical regions (especially in SAF) will be mitigated, while the risk of floods will be exacerbated in the Central Sahel.

To meet the Paris Agreement, African countries will implement mitigation measures to contribute to keep the surface air temperature below 2°C. Geoengineering with SAI is suggested as an option to meet this challenge, but its implication on the African climate system needs a deep investigation in the aim to understand the impacts on temperature and precipitation extremes. To the best of the authors’ knowledge, this study is the first to investigate the potential impact of SAI using the G4 experiment of GeoMIP on temperature and precipitation extremes of the African continent.

A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.

In this study, we aim to understand how the relationship between state and business elites and underlying power dynamics develop in the face of neoliberalism and globalization in a state-dependent context. For this purpose, we draw on a qualitative research with in-depth interviews with elites from 65 companies which are ranked among the 500 largest Turkish firms by the Istanbul Chamber of Industry. Major contribution of this work is that we illustrate how globalization or internationalization provides a limited tool for business elites to escape the domination of the state in a state-dependent context. The only exceptions to this rule of state domination among business elites are the elites who hold double citizenships and whose initial investment background is in a foreign country. This exceptional group of elites enjoyed higher latitude of action in their interactions with the state. For the rest, state remains as an influential mechanism of coercive power to which elites are subjected. Last but not least, in spite of the connections between business growth and the state, the business elites are generally distrustful of politics and politicians and this mistrust is manifested in different ways. Overall, we illustrate the significance of the historical context and turning points in accounting for the changing nature of the relationship between elites and the state in Turkey.

The purpose of this paper is to discuss the external and internal factors that support or challenge a possible transformation of Arctic Sweden into a major ski destination under a changing climate.

The paper questions future availability of the physical and the human factors that foster ski tourism development in Arctic Sweden and suggests a comparative case study in relation to the already existing large resort-based ski destinations in Arctic Finland.

Preliminary documentary analysis shows that the governmental and the industrial discourses over the past decade have acknowledged a competitive edge for Sweden and its northernmost regions in particular and may even propose a structural shift for ski tourism in the near future agenda. The visualisations based on natural snow projections presented in this paper confirm this comparative advantage but other technical and socioeconomic development factors are further discussed, in relation to Arctic Finland.

Future research agenda is suggested to cover, first, assessment of natural and technical snow reliability of existing and all potential ski areas in Sweden and within its competitive set extending to all the Nordics and the Alps, then, incorporation of adaptive capacities of the suppliers but especially the likely substitution tendencies of the consumers, and finally, evaluation of the overall situation in terms of the regional development needs.

It is apparent that land use conflicts will arise in case of large ski resort-based destination development in Arctic Sweden, especially around the environmentally protected areas, which are not only already important attractions for nature-based tourism but also traditional livelihoods for the Sami.

This is the first paper to discuss a potential regional and structural shift of ski tourism in Sweden.