Minimum Label Research Articles

Seasonal cooling performance of air conditioners: The importance of independent test procedures used for MEPS and labels

Minimum energy performance standards and labels are commonly used tools to reduce the household energy use thus mitigating greenhouse gas emissions. However, the technical foundation for minimum energy performance standards and labels are test procedures for rating and testing of appliances. To determine the seasonal cooling performance of air conditioners, the current test standards require fixing of the compressor speed of the units to achieve steady-state conditions; this way of operation, however, differs from real-life use. To make the seasonal cooling performance testing better reflect the real use conditions, this study proposes a compensation method which can be conducted independently from manufacturer data and still allows modulation of the tested units. Our results show that the tested units behave differently under part-load conditions, which results in a lower energy efficiency rating for some of the tested devices.

Exact values for three domination-like problems in circular and infinite grid graphs of small height

In this paper we study three domination-like problems, namely identifying codes, locating-dominating codes, and locating-total-dominating codes. We are interested in finding the minimum cardinality of such codes in circular and infinite grid graphs of given height. We provide an alternate proof for already known results, as well as new results. These were obtained by a computer search based on a generic framework, that we developed earlier, for the search of a minimum labeling satisfying a pseudo-d-local property in rotagraphs.

Algorithmic expedients for the S-labeling problem

Graph labeling problems have been widely studied in the last decades and have a vast area of application. In this work, we study the recently introduced S-labeling problem, in which the nodes get labeled using labels from 1 to |V| and for each edge the contribution to the objective function, called S-labeling number of the graph, is the minimum label of its end-nodes. The goal is to find a labeling with minimum value. The problem is NP-hard for planar subcubic graphs, although for many other graph classes the complexity status is still unknown.In this paper, we present different algorithmic approaches for tackling this problem: We develop an exact solution framework based on Mixed-Integer Programming (MIP) which is enhanced with valid inequalities, starting and primal heuristics and specialized branching rules. We show that our MIP formulation has no integrality gap for paths, cycles and perfect n-ary trees, and, to the best of our knowledge, we give the first polynomial-time algorithm for the problem on n-ary trees as well as a closed formula for the S-labeling number for such trees. Moreover, we also present a Lagrangian heuristic and a constraint programming approach. A computational study is carried out in order to (i) investigate if there may be other special graph classes, where our MIP formulation has no integrality gap, and (ii) assess the effectiveness of the proposed solution approaches for solving the problem on a dataset consisting of general graphs.

Heuristics for the strong generalized minimum label spanning tree problem

AbstractIn this work we introduce and study the strong generalized minimum label spanning tree (GMLST), a novel optimization problem defined on edge‐labeled graphs. Given a label set associated to each edge of the input graph, the aim is to look for the spanning tree using the minimum number of labels. Differently from the previously introduced GMLST problem, including a given edge in the solution means that all its labels are used. We present a mathematical formulation, as well as three heuristic approaches to solve the problem. Computational results compare the performances of the proposed algorithms.

Multi-objective evolutionary algorithm on simplified bi-objective minimum weight minimum label spanning tree problems

Multi-objective evolutionary algorithm on simplified bi-objective minimum weight minimum label spanning tree problems

Multi-objective evolutionary algorithm on simplified bi-objective minimum weight minimum label spanning tree problems

As general purpose optimisation methods, evolutionary algorithms have been efficiently used to solve multi-objective combinatorial optimisation problems. However, few theoretical investigations have been conducted to understand the efficiency of evolutionary algorithms on such problems, and even fewer theoretical investigations have been conducted on multi-objective combinatorial optimisation problems coming from real world. In this paper, we analyse the performance of a simple multi-objective evolutionary algorithm on two simplified instances of the bi-objective minimum weight minimum label spanning tree problem, which comes from real world. Though these two instances are similar, the analysis results show that the simple multi-objective evolutionary algorithm is efficient for one instance, but it may be inefficient for the other. According to the analysis on the second instance, we think that the restart strategy may be useful in making the multi-objective evolutionary algorithm more efficient for the bi-objective problem.

Penerapan Label Pangan pada Produk Bagiak oleh Produsen di Banyuwangi

Food packaging that provides food labels to inform consumers about product quality. Food labeling is done with the aim of providing a sense of security to consumers without having to open the product packaging. Supervision conducted by the Department of Industry and Trade and the Health Service in 12 sub-districts in Banyuwangi district, industrial owners do not have PIRT and do not know the food label conditions. This can increase the potential for insecurity and insecure quality. Packaging food from Banyuwangi area is for the production of home industry in the form of packaging. The objective of the study was to evaluate food labels in household industries that produce diets in Banyuwangi. The research design is cross sectional with observation method in 12 household industries conducted at the Trade Industry Service of Banyuwangi Regency. The data collection used a questionnaire survey on the results of an industrial sample. Descriptive data analysis, presented in proportion to tables and narratives. The results obtained 50% of 12 household products have met the minimum label criteria in accordance with Government Regulation No.69 of 1999 on Food Label and Advertisement. The lower inclusion of the manufacturer's name and address affects the product in the completeness of the label attribute.

Path queries on functions

Let f:[1..n]→[1..n] be a function, and ℓ:[1..n]→[1..σ] indicate a label assigned to each element of the domain. We design several compact data structures that answer various kinds of summary queries on the labels of paths in f. For example, we can find either the minimum label in fk(i) for a given i and any k≥0 in a given range [k1..k2], or the minimum label in f−k(i) for a given i and k>0, using nlg⁡n+nlg⁡σ+o(nlg⁡n) bits and time O(α(n)), the inverse Ackermann function. Within similar space we can count, in time O(lg⁡n/lg⁡lg⁡n), the number of labels within a range, and report each element with such labels in O(lg⁡n/lg⁡lg⁡n) additional time. Several other tradeoffs and possible queries are considered, such as selection, top-r queries and τ-majorities. Finally, we consider queries that allow us navigate on the graph of the function, such as the nearest common successor of two elements, or the nearest successor or predecessor of an element within a range of labels.

A hybrid metaheuristic for the minimum labeling spanning tree problem

An edge-labeled graph (ELG) is a graph in which each edge has a label associated. Given G, an ELG, the minimum labeling spanning tree problem (MLSTP) is an NP-hard problem that consists in finding a spanning tree in G by using a minimum number of labels. The MLSTP has applications in areas such as computer networks, multimodal transportation networks, and data compression. This paper introduces new concepts, presents a revised version of the maximum vertex covering algorithm and provides a tighter bound to its time complexity. Further, a new MIP-based metaheuristic is proposed for solving the MLSTP, the multi-start local branching (MSLB). It combines the efficiency of the proposed constructive heuristics with the capacity of exploration of a new local search method based on MIP. The computational experiments performed show that the MSLB is superior to the current state-of-the-art metaheuristics in respect to quality of the solutions and processing times.

A polyhedral approach to the generalized minimum labeling spanning tree problem

The minimum labeling spanning tree problem (MLSTP) is a combinatorial optimization problem that consists in finding a spanning tree in a simple graph G, in which each edge has one label, by using a minimum number of labels. It is an NP-hard problem that was introduced by Chang and Leu (Inf Process Lett 63(5):277–282, 1997. https://doi.org/10.1016/S0020-0190(97)00127-0 ). Chen et al. (Comparison of heuristics for solving the gmlst problem, in: Raghavan, Golden, Wasil (eds) Telecommunications modeling, policy, and technology, Springer, Boston, pp 191–217, 2008) subsequently proposed a generalization of the MLSTP, called the generalized minimum labeling spanning tree problem (GMLSTP), that allows a situation in which multiple labels can be assigned to an edge. Here, we show how the GMLSTP can be expressed as an MLSTP in a multigraph. Both problems have applications in various areas such as computer network design, multimodal transportation network design, and data compression. We propose a new compact binary integer programming model to solve exactly the GMLSTP and analyze the polytope associated with the formulation. The paper introduces new concepts, gives the polytope dimension, and describes five new facet families. The polyhedral comparison results for the studied polytope show that the new model is theoretically superior to current state-of-the-art formulations.

Efficient heuristics for the minimum labeling global cut problem

Let G=(V,E,L) be an edge-labeled graph. Let V be the set of vertices of G, E the set of edges, L the set of labels (colors) such that each edge e∈E has an associated label L(e). The goal of the minimum labeling global cut problem (MLGCP) is to find a subset L′⊆L of labels such that G′=(V,E′,L\\L′) is not connected and |L′| is minimized. In this work, we generate random instances for the MLGCP to perform empirical tests. Also propose a set of heuristics using concepts of Genetic Algorithm and metaheuristic VNS, including some of their procedures, like two local search moves, and an auxiliary data structure to speed up the local search. Computational experiments show that the metaheuristic VNS outperforms other methods with respect to solution quality.

Minimum quality standards and compulsory labeling when environmental quality is not observable

This paper studies the effect of a minimum quality standard, a compulsory labeling scheme, and the combination of both instruments in a vertical differentiation model when not all quality dimensions can be observed by consumers. Both a minimum quality standard for the non-observable quality dimension and a labeling scheme that informs consumers about the non-observable quality dimension increase prices and have no effect on the observable quality dimension or market shares. The combination of a minimum quality standard and a labeling scheme increases both the unobservable and the observable quality dimension, increases prices, and shifts market shares from the high quality firm to the low quality firm. Social welfare is higher under the combination of both instruments than under no regulation, the minimum quality standard or labeling applied as only instrument.

L(2,1)-Edge-Labelings of the Edge-Path-Replacement of a Graph

Two edges [Formula: see text] and [Formula: see text] in a graph [Formula: see text] are said to be adjacent if they have a vertex in common, and distance two apart if they are nonadjacent but both are adjacent to a common edge. An [Formula: see text]-edge-labeling of a graph [Formula: see text] is an assignment of nonnegative integers, called labels, to the edges of [Formula: see text] such that the difference between labels of any two adjacent edges is at least [Formula: see text], and the labels of any two edges that are distance two apart are different. The span of an [Formula: see text]-edge-labeling of a graph [Formula: see text] is the difference between the maximum and minimum labels. The minimum span over all [Formula: see text]-edge-labelings of a graph [Formula: see text] is called the [Formula: see text]-edge-labeling number of [Formula: see text], denoted by [Formula: see text]. For [Formula: see text], the edge-path-replacement of a graph [Formula: see text], denoted by [Formula: see text], is a graph obtained by replacing each edge of [Formula: see text] with a path [Formula: see text] on [Formula: see text] vertices. This paper investigates the [Formula: see text]-edge-labeling number of the edge-path-replacement [Formula: see text] of a graph [Formula: see text] for [Formula: see text]. We get the following main results: [Formula: see text] Let [Formula: see text] be a graph with maximum degree [Formula: see text] and [Formula: see text] be an integer not less than [Formula: see text], then [Formula: see text] if [Formula: see text] is odd, and otherwise [Formula: see text]. [Formula: see text] Let [Formula: see text] be a graph with maximum degree [Formula: see text]. Then [Formula: see text] when [Formula: see text] is even, and [Formula: see text] when [Formula: see text] is odd.

Direct assignment of 13C solid-state NMR signals of TFoF1 ATP synthase subunit c-ring in lipid membranes and its implication for the ring structure.

FoF1-ATP synthase catalyzes ATP hydrolysis/synthesis coupled with a transmembrane H+ translocation in membranes. The Fo c-subunit ring plays a major role in this reaction. We have developed an assignment strategy for solid-state 13C NMR (ssNMR) signals of the Fo c-subunit ring of thermophilic Bacillus PS3 (TFo c-ring, 72 residues), carrying one of the basic folds of membrane proteins. In a ssNMR spectrum of uniformly 13C-labeled sample, the signal overlap has been a major bottleneck because most amino acid residues are hydrophobic. To overcome signal overlapping, we developed a method designated as COmplementary Sequential assignment with MInimum Labeling Ensemble (COSMILE). According to this method, we generated three kinds of reverse-labeled samples to suppress signal overlapping. To assign the carbon signals sequentially, two-dimensional Cα(i+1)-C'Cα(i) correlation and dipolar assisted rotational resonance (DARR) experiments were performed under magic-angle sample spinning. On the basis of inter- and intra-residue 13C-13C chemical shift correlations, 97% of Cα, 97% of Cβ and 92% of C' signals were assigned directly from the spectra. Secondary structure analysis predicted a hairpin fold of two helices with a central loop. The effects of saturated and unsaturated phosphatidylcholines on TFo c-ring structure were examined. The DARR spectra at 15ms mixing time are essentially similar to each other in saturated and unsaturated lipid membranes, suggesting that TFo c-rings have similar structures under the different environments. The spectrum of the sample in saturated lipid membranes showed better resolution and structural stability in the gel state. The C-terminal helix was suggested to locate in the outer layer of the c-ring.

Devolutionary genetic algorithms with application to the minimum labeling Steiner tree problem

This paper characterizes and discusses devolutionary genetic algorithms and evaluates their performances in solving the minimum labeling Steiner tree (MLST) problem. We define devolutionary algorithms as the process of reaching a feasible solution by devolving a population of super-optimal unfeasible solutions over time. We claim that distinguishing them from the widely used evolutionary algorithms is relevant. The most important distinction lies in the fact that in the former type of processes, the value function decreases over successive generation of solutions, thus providing a natural stopping condition for the computation process. We show how classical evolutionary concepts, such as crossing, mutation and fitness can be adapted to aim at reaching an optimal or close-to-optimal solution among the first generations of feasible solutions. We additionally introduce a novel integer linear programming formulation of the MLST problem and a valid constraint used for speeding up the devolutionary process. Finally, we conduct an experiment comparing the performances of devolutionary algorithms to those of state of the art approaches used for solving randomly generated instances of the MLST problem. Results of this experiment support the use of devolutionary algorithms for the MLST problem and their development for other NP-hard combinatorial optimization problems.

Carousel greedy: A generalized greedy algorithm with applications in optimization

In this paper, we introduce carousel greedy, an enhanced greedy algorithm which seeks to overcome the traditional weaknesses of greedy approaches. We have applied carousel greedy to a variety of well-known problems in combinatorial optimization such as the minimum label spanning tree problem, the minimum vertex cover problem, the maximum independent set problem, and the minimum weight vertex cover problem. In all cases, the results are very promising. Since carousel greedy is very fast, it can be used to solve very large problems. In addition, it can be combined with other approaches to create a powerful, new metaheuristic. Our goal in this paper is to motivate and explain the new approach and present extensive computational results.

Efficacy of a new spot-on formulation of selamectin plus sarolaner for cats against adult Ctenocephalides felis, flea egg production and adult flea emergence

A new spot-on formulation of selamectin plus sarolaner was evaluated against fleas for adulticidal efficacy, and for the effect on egg production and hatching when applied to flea-infested cats. Ten male and ten female adult domestic shorthair cats were randomly assigned to one of two treatment groups based on pre-treatment flea counts. Cats received topical treatment on Day 0 in a single spot to the dorsal scapular area with either a placebo formulation or with the combination formulation at the minimal dose of 6.0mg selamectin plus 1.0mg sarolaner per kg bodyweight. On Days −1, 5, 12, 19, 26 and 33, cats were infested with approximately 100 (±5) unfed Ctenocephalides felis fleas. At 24h after treatment or 48h after subsequent flea infestation, cats were housed for a 20-h period in a cage to allow collection of flea eggs. At the end of this period, flea eggs were collected from the cages and cats were combed to remove and count live fleas. Emerged viable larvae and emerged adult fleas were counted 3days and 35days, respectively, after egg collection. The new spot-on formulation of selamectin plus sarolaner provided 100% efficacy against adult fleas up to Day 36 following a single application. Fleas on placebo-treated cats produced large numbers of eggs throughout the study, with individual counts ranging from 110 to 1256 eggs. Following treatment, four flea eggs were collected from a single selamectin/sarolaner-treated cat on Day 29, but there were no eggs collected from any other selamectin/sarolaner-treated animal during the study. No larvae or adult fleas developed from these four eggs. From the eggs collected from the placebo-treated cats, the mean percentage of live larvae and adults that emerged ranged from 67.3% to 84.2% and from 50.7% to 81.8%, respectively. A single topical treatment with a new spot-on formulation of selamectin plus sarolaner at the minimum label dose thus controlled fleas on cats and was 100% effective in preventing flea reproduction for over one month after treatment.

Efficacy of a new spot-on formulation of selamectin plus sarolaner against Ancylostoma tubaeforme and Toxocara cati in cats

The efficacy of a new spot-on formulation of selamectin plus sarolaner for cats was evaluated against induced infections with Ancylostoma tubaeforme (hookworm) and Toxocara cati (roundworm). Five laboratory studies were conducted using adult, purpose-bred cats. Four of the studies were designed to evaluate efficacy of the combination against A. tubaeforme, the dose-limiting gastrointestinal nematode species for selamectin. In two of these studies non-interference between selamectin and sarolaner was also evaluated. The fifth study evaluated efficacy of the combination against mixed infections of A. tubaeforme and T. cati. The hookworm isolates in three studies were of US origin, as was the roundworm isolate. In the two remaining studies, cats were inoculated with a hookworm isolate of European origin. Cats were inoculated with 150 (±50) to 200 (±50) infective hookworm larvae 30–42days prior to treatment and with 400 infective roundworm eggs 60days prior to treatment. Cats were ranked by pre-treatment faecal egg counts and randomly allocated to different treatment groups. In all studies, cats were treated at the minimum label dose to provide 6.0mg selamectin per kg bodyweight. All animals were euthanized 7–10days after treatment for worm counts. Efficacy was calculated based on the reduction of the geometric mean worm counts in the treated groups versus the placebo-treated control groups.The efficacy against adult hookworms was 99.2%, 94.3% and 100% in three of these studies, and was lower in the remaining two studies. The efficacy against T. cati was 100%. Furthermore, non-interference between sarolaner and selamectin was demonstrated. Thus, a single topical application of the new spot-on formulation of selamectin plus sarolaner at the minimum label dose is effective in the treatment of adult hookworm and roundworm infections in cats.

Speed of kill of a new spot-on formulation of selamectin plus sarolaner for cats against induced infestations with Ixodes ricinus

The speed of kill of a new spot-on formulation containing selamectin plus sarolaner (Stronghold®Plus, Zoetis) for cats was evaluated against Ixodes ricinus ticks in a placebo-controlled, blinded study. Sixteen (16) cats were blocked by pre-treatment tick counts and randomly allocated to the placebo-treated group or the selamectin/sarolaner-treated group. Cats either received a single topical treatment at the minimum dose of 6.0mg selamectin and 1.0mg sarolaner per kg bodyweight or a placebo formulation on Day 0. On Days -2, 7, 14, 21, 28 and 35, cats were infested with approximately 50 unfed, viable and adult I. ricinus ticks. Tick counts were performed in situ 8 and 12h after treatment or re-infestation. Ticks were removed from the cats and counted at the 24h tick count. Acaricidal efficacy at each time point was calculated based on the reduction of mean live tick counts in the selamectin/sarolaner-treated group versus the placebo-treated group.There were no treatment-related adverse reactions during the study. Placebo-treated cats maintained infestations with mean tick counts ranging from 10.3 to 21.9 throughout the study. The new spot-on formulation of selamectin plus sarolaner demonstrated 99.3% efficacy (P<0.0001) within 24h after treatment against pre-existing infestations. For subsequent re-infestations, efficacy was >97.9% for at least 3 weeks and was 89.0% after the re-infestation on Day 28. Mean live tick counts were significantly reduced by 12h after re-infestation for at least 28 days (P<0.0338). Thus, a single application of the new spot-on formulation of selamectin plus sarolaner at the minimum label dose started killing ticks within 24h after treatment and within 12h after re-infestations for 4 weeks. High acaricidal efficacy was achieved within 24h after treatment and this persisted following subsequent re-infestations for a month.

Competition between For-Profit and Industry Labels: The Case of Social Labels in the Coffee Market

We model strategic interaction on a market where two labeling organizations compete and firms in duopoly decide which labels to offer. The incumbent label maximizes its own profit, and is challenged by an industry standard which maximizes industry profit. Using a nested logit, the result of this multi-stage game depends crucially on the degree of horizontal differentiation. Joint firm profit always increases with the introduction of the industry standard. The industry standard wants to segment the market and strategically distorts its label quality downwards, such that each firm specializes in a different label. Social welfare however increases with the number of labeled products. A policy imposing a minimum label quality is only binding in the case of strategic quality distortion by the industry standard.