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Abstract
This article explores how chieftains on the southwest periphery during the Ming-Qing transition conducted long-term plans to formulate cultural and literary heritages that had an affinity with Han Chinese mainstream culture but also retained indigenous qualities. The author demonstrates that the boundaries between Han and non-Han peoples became more negotiable with the enterprising efforts of chieftains to "perform" civilization by way of literary activities. The discussion centers on Rongmei jiyou (My Travel to Rongmei), a travelogue in diary form by early Qing scholar and playwright Gu Cai.

Proceeding of: IEEE 95th Vehicular Technology Conference (VTC2022-Spring), Helsinki, Finland, 19-22 June 2022 ; In this work, a spike-QAM, a regular QAM constellation where one to four of the elements with the largest amplitudes are placed further from the center, is proposed as the optimum constellation that minimizes the ratio of the symbolerror-rate (SER) to peak-to-average-power-ratio (PAPR) in simultaneous-wireless-information-and-power-transfer (SWIPT) applications. This constellation is capable of maximizing the SER performance for a given design PAPR, or maximize the PAPR given a SER performance. The relationship between these parameters is defined. An approximation to the SER performance is given for the spike-QAM in AWGN channels and it is demonstrated to be valid via numerical simulations. ; This work has received funding from the European Union Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie ETN TeamUp5G, grant agreement No. 813391, and the Spanish National Project IRENE-EARTH (PID2020-115323RB-C33) (MINECO/AEI/FEDER, UE).

Proceedings of: IEEE Global Communications Conference (GLOBECOM), 9-11 December 2021, Madrid. ; A rigorous analysis of the effect of spatial corre-lation for non-coherent (NC) massive multiple-input-multiple-output (MIMO) in Rician channels is important to determine its applicability in these scenarios. We conduct such analysis for a single base station (BS) and a more general case of several BSs, all of them showing correlation among their own antennas but with uncorrelated channels with respect to each other. We first perform an analysis of the distribution of the received symbols, then propose some approximations to give a closed form expression of the symbol error probability (SER) and the signal-to-interference-and-noise-ratio (SINR) as performance measures. Finally, we extract some conclusions from this analysis to show how the combined use of several BSs and larger Rician components can be beneficial in this scenario. Some numerical results are added to confirm the accuracy of the analysis. ; This work has received funding from the European Union Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie ETN TeamUp5G, grant agreement No. 813391, and the Spanish National Project TERESA-ADA (TEC2017-90093-C3-2-R) (MINECO/AEI/FEDER, UE).

Proceeding of: 12th IEEE/IET International Symposium on Communication Systems, Networks and Digital Signal Processing, (CSNDSP), 20-22, July 2020, (Online). ; The performance of communication systems dependson the choice of constellations, designed in an end-to-endmanner. In case of a mathematical intractability, either becauseof complexity or even lack of channel model only sub-optimal solutionscan be provided with an analytical approach. We presentend-to-end learning, a recent technique in communications tolearn optimal transmitter and receiver architectures based ondeep neural networks (DNNs) architectures. We discuss cases inwhich this technique has been used to design constellations inwhich channel model intractability repressed from a mathematicalanalysis. ; This work has received funding from the European Union (EU) Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie ETN TeamUp5G, grant agreement No. 813391, and from the Spanish National Project TERESA-ADA (TEC2017-90093-C3-2-R) (MINECO/AEI/FEDER, UE).

Pilot symbol assisted modulation (PSAM) is widely used to obtain the channel state information (CSI) needed for coherent demodulation. It allows the density of pilot symbols to be dynamically chosen depending on the channel conditions. However, the insertion of pilots reduces the spectral efficiency, more severely when the channel is highly time-variant and/or frequency-selective. In these cases a significant amount of pilots is required to properly track the channel variations in both time and frequency dimensions. Alternatively, non-coherent demodulation does not require any CSI for the demodulation independently of the channel conditions. For the particular case of up-link (UL) based on massive single input -multiple output (SIMO) combined with orthogonal frequency division multiplexing (OFDM), we propose to replace the traditional reference signals of PSAM by a new differentially-encoded data stream that can be non-coherently detected. The latter can be demodulated without the knowledge of the CSI and subsequently used for the channel estimation. We denote our proposal as hybrid demodulation scheme (HDS) because it exploits both the benefits of a coherent demodulation scheme (CDS) and a non-coherent demodulation scheme (NCDS) to increase the spectral efficiency. The mean squared error (MSE) of the channel estimation, bit error rate (BER), achieved throughput and complexity are analyzed to highlight the benefits of this differential data-aided channel estimation as compared to other approaches. We show that the channel estimation is almost as good as PSAM, while the BER performance and throughput are improved for different channel conditions with a very small complexity increase. ; This work has received funding from the European Union (EU) Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie ETN TeamUp5G, grant agreement No. 813391, and from the Spanish National Project TERESA-ADA (TEC2017-90093-C3-2-R) (MINECO/AEI/FEDER, UE).

Military uniforms serve as an essential symbol for servicemen and an important image of national and military dignity. The current military uniform size system in Taiwan, which features various types of military uniforms based on the body sizes of servicemen, was formulated in 1986. This size classification system includes numerous groups and is too complex, leading to inventory overstock, increased inventory cost and warehouse staff workload, and a waste of national defense resources. This study used support vector clustering (SVC) with genetic algorithm (GA) models to improve the upper garment size system for uniforms. The SVC technique was employed to classify sizes, and the GA technique was used to determine optimal parameter values for the SVC model. This paper developed an upper garment size system that can increase the fit of uniforms to servicemen&rsquo ; s body sizes and reduce the number of size groups, thereby alleviating warehouse staff workload and inventory cost.

AbstractIt has been challenging for firms to effectively manage demand when they release products of one generation after another one. Motivated by the observations from the smartphone industry, this paper investigates the effectiveness of two demand management strategies in the presence of a product rollover: the upgrade program and price markdown policy. Under an upgrade program, a firm allows customers to upgrade their on‐hand product to a new generation product that will be released in a future time. Under a markdown pricing policy, the firm offers a discount for the currently available product so as to induce waiting customers to make immediate purchases. The two demand management strategies target different groups of customers and have distinct impacts on customers' choices. Starting from the time‐varying choice behavior of a heterogeneous group of customers, we study the optimal pricing decisions involved in the two strategies. Specifically, when customers are myopic in the sense that they only make a one‐time purchasing decision upon arrival, we show that the firm should offer the upgrade program only when the innovation level of the new product is relatively high, and the firm's optimal upgrade price can increase over time. Generally, the firm should offer the upgrade program during the early selling period and adopt markdown pricing as the release date of the new product approaches. Numerical experiments reveal that the dynamic upgrade program and markdown pricing policies can help improve profit significantly. When customers are strategic in the sense that they can monitor the selling prices and make dynamic purchasing decisions until they buy a unit of product, we examine two coping strategies that a firm can adopt, and investigate how the strategic monitoring behavior may influence a firm's optimal selling decisions and profit.