SECOND: Sparsely Embedded Convolutional Detection

Yan Yan, Yuxing Mao, Bo Li · Sensors · 2018 · computer-science · 10.3390/s18103337 · record yan2018-second-sparsely-embedded-convoluti
tag layer · index · concepts · authors · עברית
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Other fields define these differently the same word, defined another way in another discipline
orientation 2 fields

Tags on this paper

Every tag the record carries, each linking to every other paper in the corpus that carries it. A tag appears here whether or not its words occur in the article — the spans below are only the ones a sentence in this paper licenses. Of the 8 concept tags on this paper, all 8 are grounded in a quoted sentence. All carry the tagger's gloss of what the term means in this paper, which is not something the article can license.
sparse convolution angle regression corner encoding direction classifier ground truths anchors VoxelNet KITTI sampling ground truths from a database collision rejection after sampling per-object rather than per-scene noise orientation average precision (AP) system-or-tool-building
Method, as described: training and evaluation on the KITTI 3D detection benchmark, with ablations on sparse convolution, angle encoding and ground-truth sampling

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relation to other workclaim_relationshow this paper stands to another: agrees, contradicts, extends, qualifies
claim typeclaim_typethe shape of the claim: existence, mechanism, method, critique, prediction, null
concept edgeconcept_edgesan asserted relation between two concepts, with the sentence asserting it
conceptconceptsan idea the paper works with, quoted where the paper uses it
content tagcontent_tagsa finding, definition, quantity, statistic or variable named in the paper
contributioncontributionwhat the paper claims to add
controlcontrolsan experiment run to eliminate a rival explanation
limitationlimitationswhat the paper says its evidence cannot support
mechanismmechanismshow the reported effect is said to come about
methodmethodhow the paper produced its evidence
object of studyobject_of_studywhat the paper is about — the thing it investigates
phenomenonphenomenonthe effect or regularity under study
research questionresearch_questionthe question the paper sets itself
sensesensesa distinct use of a term, quoted where the paper fixes it
transfertransfersa method or concept carried in from another field

The paper

The full text is not reproduced here. This article is not cleared for redistribution, so the page carries the tag layer only. Its evidence sentences are withheld; the grounding status remains with each tag, and the article itself is at https://doi.org/10.3390/s18103337. The reading view exists for the papers whose licence permits it.

Every tag on this page

claim_relations 3 · claim_type 1 · concept_edges 1 · concepts 8 · content_tags 14 · contribution 1 · controls 4 · limitations 3 · mechanisms 3 · method 1 · object_of_study 1 · phenomenon 1 · research_question 1 · senses 5 · transfers 1

Relations on this page carry a quotation for the claim. Where a relation was separately evidenced — and so tested against the vocabulary for its type — the row says so; none of 1 relation here carry that mark. The rest are the tagger’s reading of the sentence quoted beside them.

facettagfieldconf.whose words
object_of_study3D object detection from LiDAR point clouds, and the speed and orientation-accuracy limits of voxel-based convolutional detectors
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object_of_studythe paper's words
research_questionhow to keep the information a 3D voxel representation preserves while removing the inference cost and the orientation error that come with it
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research_questionthe paper's words
contributionsparse convolution with a GPU rule-generation algorithm, a sine-error angle loss with a separate direction classifier, and ground-truth sampling augmentation
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contributionthe paper's words
claim_typemethod
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claim_typethe paper's words
phenomenonan ill-posed regression target: two orientation values that describe the same box but generate maximal loss against each other
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phenomenonthe paper's words
methodsystem-or-tool-building
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methodthe paper's words
mechanismsobjects and their enclosed points are collected once into a database, then pasted into other point clouds during training, which multiplies the labelled objects per scene and simulates each object in new surroundings
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mechanisms[0]0.95the tagger's words
mechanismspasted objects are removed when they intersect existing ones, so the augmentation cannot produce a scene that could not physically exist
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mechanisms[1]0.95the tagger's words
mechanismseach ground truth and its points are transformed independently instead of the whole cloud being transformed together, so the augmentation varies objects relative to their scene
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mechanisms[2]0.95the tagger's words
limitationsperformance is lower for pedestrians and cyclists and for bird's-eye-view detection, which the paper states in its own conclusion
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limitations[0]0.95the tagger's words
limitationspedestrians and cyclists give fewer points per instance and higher instance density, so they are more easily confused with clutter
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limitations[1]0.95the tagger's words
limitationstest-server access was limited, so the larger model was evaluated on the test set only and the validation assessment covers the smaller model alone
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limitations[2]0.95the tagger's words
transfersthe focal loss, carried from single-stage 2D image detection into 3D point-cloud detection to handle the same foreground-background imbalance
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transfers[0]0.95the tagger's words
controlsthe same detector with dense convolution instead of sparse, to attribute the speed gain
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eliminates: a speed gain produced by the rest of the detector rather than by sparse convolution · outcome: held
controls[0]0.95the tagger's words
controlsthe angle encoding used by AVOD and ComplexYOLO, run as the comparison for the new angle loss
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eliminates: a new angle loss credited with an improvement that the encoding used by the baselines would also have produced · outcome: held
controls[1]0.95the tagger's words
controlsa physical-plausibility check on the augmented scenes
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eliminates: a detector trained on augmented scenes containing objects that could not physically coexist, which would teach it geometry no sensor will ever show it · outcome: held
controls[2]0.95the tagger's words
controlsa validation-set assessment of the larger model
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eliminates: over-fitting of the larger model to the test set - the validation-set assessment that would show it exists only for the smaller model, because access to the test server was limited · outcome: absent-declared-unreported
controls[3]0.95the tagger's words
conceptssparse convolution
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concepts[0]0.95the paper's words
conceptsangle regression
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concepts[1]0.95the paper's words
conceptscorner encoding
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
concepts[2]0.95the paper's words
conceptsdirection classifier
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
concepts[3]0.95the paper's words
conceptsground truths
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
also in: ground truths
concepts[4]0.95the paper's words
conceptsanchors
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
also in: anchors
concepts[5]0.95the paper's words
conceptsVoxelNet
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
also in: VoxelNet
concepts[6]0.95the paper's words
conceptsKITTI
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
also in: KITTI
concepts[7]0.95the paper's words
senses'orientation error' was measuring the ANGLE and not the BOX - two angles describing one box produced maximal loss
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senses[0]0.95the tagger's words
sensesthe new loss treats boxes with opposite directions as the SAME by design, and a separate classifier recovers the direction
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senses[1]0.95the tagger's words
sensesthe direction target is defined by a sign test on yaw: positive above zero, negative otherwise
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senses[2]0.95the tagger's words
senses'state of the art' here is dataset-relative: 90% AP for 2D car detection against 15% for 3D image-based
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senses[3]0.95the tagger's words
senses'real-time' is stated as a run time, not a claim - 20 fps for the large model and 40 for the small
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senses[4]0.95the tagger's words
claim_relationsextends → VoxelNet, which combines raw-point and voxel feature extraction end to end
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note: keeps the voxel approach and replaces the dense 3D convolution that made it too slow
claim_relations[0]the tagger's words
claim_relationscritiques → prior angle encodings - corner, direct and vector
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note: each is rejected for a different failure, and the replacement is a loss that changes what is being measured rather than how well
claim_relations[1]the tagger's words
claim_relationsbuilds-on → the focal loss introduced for single-stage detection
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claim_relations[2]the tagger's words
concept_edgesanchors —contrasted-with→ ground truths
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differs in: count - about 70,000 anchors against a few ground truths each yielding 4 to 6 positives · strength of the relation: 0.95 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span contrasts the NUMBERS of anchors and ground truths; contrasted-with is loose.
concept_edges[2]the tagger's words
content_tagssparse convolution gives a large speed gain over dense convolution at slight cost in performance
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content_tags.findings[0]0.95the tagger's words
content_tagsthe new angle loss outperforms the vector encoding used by two prior detectors
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content_tags.findings[1]0.95the tagger's words
content_tagsthe method reaches state-of-the-art results using LiDAR alone
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content_tags.findings[2]0.95the tagger's words
content_tagsperformance remains lower for pedestrians and cyclists than for cars
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
content_tags.findings[3]0.95the tagger's words
content_tagsangle regression
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
content_tags.definitions[0]0.95the tagger's words
content_tagsdirection classifier
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content_tags.definitions[1]0.95the tagger's words
content_tags90% AP for 2D car detection against 15% for 3D image-based car detection — None
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content_tags.quantities[0]0.95the tagger's words
content_tagsa factor-of-4 training speedup and factor-of-3 inference speedup against dense convolution — None
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content_tags.quantities[1]0.95the tagger's words
content_tagsabout 0.025 s per frame for the small model on a GTX 1080 Ti — None
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content_tags.quantities[2]0.95the tagger's words
content_tags20 fps for the larger model and 40 fps for the smaller — None
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content_tags.quantities[3]0.95the tagger's words
content_tagsabout 70,000 anchors per point cloud against a few ground truths giving 4 to 6 positives each — None
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content_tags.quantities[4]0.95the tagger's words
content_tagsaverage precision (AP)
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content_tags.statistics[0]0.95the tagger's words
content_tagsorientation
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
also in: orientation
content_tags.variables[0]0.95the tagger's words
content_tagsanchors
Quotation withheld — this record is not cleared for redistribution. The sentence is in the paper at the link above.
also in: anchors
content_tags.variables[1]0.95the tagger's words

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