Short Packet Structure for Ultra-Reliable Machine-type Communication: Tradeoff between Detection and Decoding

Machine-type communication requires rethinking of the structure of short packets due to the coding limitations and the significant role of the control information. In ultra-reliable low-latency communication (URLLC), it is crucial to optimally use the limited degrees of freedom (DoFs) to send data and control information. We consider a URLLC model for short packet transmission with acknowledgement (ACK). We compare the detection/decoding performance of two short packet structures: (1) time-multiplexed detection sequence and data; and (2) structure in which both packet detection and data decoding use all DoFs. Specifically, as an instance of the second structure we use superimposed sequences for detection and data. We derive the probabilities of false alarm and misdetection for an AWGN channel and numerically minimize the packet error probability (PER), showing that for delay-constrained data and ACK exchange, there is a tradeoff between the resources spent for detection and decoding. We show that the optimal PER for the superimposed structure is achieved for higher detection overhead. For this reason, the PER is also higher than in the preamble case. However, the superimposed structure is advantageous due to its flexibility to achieve optimal operation without the need to use multiple codebooks.Comment: Accepted at ICASSP 2018, special session on "Signal Processing for Machine-Type Communications

A systematic immunohistochemical survey of the distribution patterns of GH, prolactin, somatolactin, β-TSH, β-FSH, β-LH, ACTH, and α-MSH in the adenohypophysis of Oreochromis niloticus , the Nile tilapia

Fish pituitary plays a central role in the control of growth, development, reproduction and adaptation to the environment. Several types of hormone-secreting adenohypophyseal cells have been characterised and localised in diverse teleost species. The results suggest a similar distribution pattern among the species investigated. However, most studies deal with a single hormone or hormone family. Thus, we studied adjacent sections of the pituitary of Oreochromis niloticus, the tilapia, by conventional staining and immunohistochemistry with specific antisera directed against growth hormone (GH), prolactin (PRL), somatolactin (SL), thyrotropin (β-TSH), follicle-stimulating hormone (β-FSH), luteinising hormone (β-LH), adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormone (α-MSH). The pituitary was characterised by a close interdigitating neighbourhood of neurohypophysis (PN) and adenohypophysis. PRL-immunoreactive and ACTH-immunoreactive cells were detected in the rostral pars distalis. GH-immunoreactive cells were present in the proximal pars distalis (PPD). A small region of the PPD contained β-TSH-immunoreactive cells, and β-LH-immunoreactive cells covered approximately the remaining parts. Centrally, β-FSH-immunoreactive cells were detected in the vicinity of the GH-containing cells. Some of these cells also displayed β-LH immunoreactivity. The pars intermedia was characterised by branches of the PN surrounded by SL-containing and α-MSH-immunoreactive cells.The ACTH and α-MSH antisera were observed to cross-react with the respective antigens. This cross-reactivity was abolished by pre-absorption. We present a complete map of the distinct localisation sites for the classical pituitary hormones, thereby providing a solid basis for future research on teleost pituitar

Evaluation of dried amorphous ferric hydroxide CFH-12® as agent for binding bioavailable phosphorus in lake sediments

Metal hydroxides formed from aluminum (Al) and iron (Fe) salts can be used as phosphorus (P) adsorbents in lake restoration, but the application entails problems in low-alkaline lakes due to acid producing hydrolysis and potential formation of toxic metal ions. Therefore, we tested the potential of applying CFH-12® (Kemira) – a dried, amorphous Fe-oxide with no pH effect – in lake restoration. Since Fe3+ may become reduced in lake sed- iments and release both Fe2+ and any associated P we also evaluated the redox sensitivity of CFH-12® in com- parison with freshly formed Fe(OH)3. CFH-12® was added to undisturbed sediment cores from three Danish lakes relative to the size of their mobile P pool (molar Fe:PMobile dose ratio of ~10:1), and P and Fe fluxes across the sediment-water interface were compared with those from untreated cores and cores treated with freshly formed Fe(OH)3. Under anoxic conditions, we found that CFH-12® significantly reduced the P efflux from the sediments (by 43% in Lake Sønderby, 70% in Lake Hampen and 60% in Lake Hostrup) while the Fe 2+ efflux remained unchanged relative to the untreated cores. Cores treated with freshly formed Fe(OH)3 retained more P, but released significantly more Fe 2+ , indicating continued Fe3+ reduction. Finally, experiments with pure phases showed that CFH-12® adsorbed less P than freshly formed Fe(OH)3 in the short term, but was capable of adsorbing up to 70% of P adsorbed by Fe(OH)3 over 3 months. With product costs only 30% higher than Al salts we find that CFH-12® has potential for use in restoration of low-alkaline lakes.The study was supported by Junta de Andalucía (project P10-RNM- 6630, Spain), MINECO CTM (project 2013-46951-R, Spain) and by the European Regional Development Fund (ERDF). Funding was also ob- tained from the Danish Centre for Lake Restoration (a Villum Centre of Excellence).The study was supported by Junta de Andalucía (project P10-RNM- 6630, Spain), MINECO CTM (project 2013-46951-R, Spain) and by the European Regional Development Fund (ERDF). Funding was also ob- tained from the Danish Centre for Lake Restoration (a Villum Centre of Excellence)

Ny forskning i grammatik

Many Danish cognition verbs take both indicative and infinitive complements. We examine what the contrast between the two complement types codes. The literature offers two answers. One is that the contrast has to do with coreferentiality: if the cognition verb’s primary argument is coreferential with the primary argument of the complement, the complement tends to be infinitive; if not, the complement must be indicative. The other answer concerns the contrast between propositions and states-of-affairs: the indicative complement designates a proposition, the infinitive complement a state-of-affairs. Corpus studies support both answers. They also support an analysis of indicatives as proposition markers. But infinitives cannot – straightforwardly – be analysed as state-of-affairs markers

Kognitionsverber og kontrasten mellem indikativ- og infinitivkomplement

Many Danish cognition verbs take both indicative and infinitive complements. We examine what the contrast between the two complement types codes. The literature offers two answers. One is that the contrast has to do with coreferentiality: if the cognition verb’s primary argument is coreferential with the primary argument of the complement, the complement tends to be infinitive; if not, the complement must be indicative. The other answer concerns the contrast between propositions and states-of-affairs: the indicative complement designates a proposition, the infinitive complement a state-of-affairs. Corpus studies support both answers. They also support an analysis of indicatives as proposition markers. But infinitives cannot – straightforwardly – be analysed as state-of-affairs markers

Grammatikalisering af type-konstruktioner og pseudo-partitiver i dansk

The aim of this paper is to argue that Danish type-noun binominals (en slags cykel ‘a kind of bike’) and pseudo-partitive binominals (et stykke ost ‘a piece of cheese’) with the formal structure [N1 + N2] have followed analogical patterns of grammaticalization both structurally and functionally. On the basis of a study of 2946 tokens of slags ‘kind’ in the construction EN/ET-slags-S(noun), retrieved from KorpusDK, we discuss agreement features and polysemy in relation to the fact that slags occurs more frequently as a modifier marking ‘association’ than with its original taxonomic meaning. Against this background, we suggest that ultimately N2 is winning the competition for discourse prominence over slags, which, thus, is in the process of converting from a lexical to a grammatical element

On the Activity Enhancing Role of Iron Oxide for Noble Metal Oxidation Catalysts: A CVD-Based Study with Differently Structured Combinations of Pt and FeOₓ Coatings on Al₂O₃

With regard to the catalysis of oxidation reactions by noble metals, the addition of FeOx to an Al2O3-supported Pt catalyst is known to be energetically more favorable compared to only Pt. In this work, different process routes for the preparation of such Fe-promoted Pt/Al2O3 catalysts via atmospheric chemical vapor deposition (CVD) in a fluidized bed were explored. Specifically, the question of whether it would be advantageous to deposit the Fe before, along with, or after the Pt was addressed, and new information was obtained about the optimum FeOx–Pt interface and mixing ratio. Vapors of Trimethyl(methylcyclopentadienyl)platinum(IV) and/or Ethyl-ferrocene were injected into the bed from the top, permitting a quasi-lossless precursor operation and a very good control of the deposited metal, and hence of the catalyst structure. Samples could be extracted from the top while CVD was ongoing to obtain time-resolved data. The catalytic activity was determined through CO oxidation. The Fe-Pt mixing ratio was then varied for the most active deposition sequence, in order to identify an activity optimum generated by the minimum amount of Pt catalyst. When compared to pure Pt/Al2O3, the optimum catalyst consistently showed superior performance even after thermal stres