Identifies that a value must be greater than that set by the constraint.

标识一个值必须大于约束设置的值。

Identifies that a value must be either greater than or equal to that set by the constraint.

标识一个值必须大于或等于约束设置的值。

Identifies that a value must be less than that set by the constraint.

标识一个值必须小于约束设置的值。

Identifies that a value must be either less than or equal to that set by the constraint.

标识一个值必须小于或等于约束设置的值。

Identifies that a value must be equal to that set by the constraint.

标识一个值必须等于约束设置的值。

Identifies that a value must be not equal to that set by the constraint.

标识一个值不能等于约束设置的值。

Identifies that an aggregation (set, list or table) must include the value (individual item) set by the constraint.

标识一个聚合(集合、列表或表)必须包含由约束设置的值(单个项)。

Identifies that an aggregation (set, list or table) must not include the value (individual item) set by the constraint.

标识一个聚合(集合、列表或表)不能包含由约束设置的值(单个项)。

Identifies that a value (individual item) must be included in the aggregation (set, list or table) set by the constraint.

标识一个值(单独的项)必须包含在由约束设置的聚合(集合、列表或表)中。

Identifies that a value (individual item) must not be included in the aggregation (set, list or table) set by the constraint.

标识一个值(单独的项)不能包含在约束设置的聚合(集合、列表或表)中。

Qualifies a constraint such that it must be followed rigidly within or at the values set.

限定约束，使其必须在值集内或值集处严格遵循。

Qualifies a constraint such that it should be followed within or at the values set.

限定约束，使其在值集内或值集处遵循。

Qualifies a constraint such that it is advised that it is followed within or at the values set.

限定约束，建议在设置的值内或值处遵循该约束。

A user-defined grade indicated by a separate attribute at the referencing entity.

由引用实体的单独属性指示的用户定义等级。

Grade has not been specified.

没有指定等级。

Defines a relationship between operands whereby the result is true if all operands are true, and false if at least one operand is false.

定义操作数之间的关系，其中如果所有操作数都为真则结果为真，如果至少有一个操作数为假则结果为假。

Defines a relationship between operands whereby the result is true if at least one operand is true, and false if all operands are false.

定义操作数之间的关系，其中如果至少有一个操作数为真，则结果为真，如果所有操作数为假，则结果为假。

Defines a relationship between operands whereby the result is true if exactly one operand is true (exclusive or).

定义操作数之间的关系，其中如果恰好一个操作数为真，则结果为真(互斥或)。

Defines a relationship between operands whereby the result is true if at least one operand is false, and false if all operands are true.

定义操作数之间的关系，其中如果至少有一个操作数为假，则结果为真，如果所有操作数为真，则为假。

Defines a relationship between operands whereby the result is true if all operands are false, and false if at least one operand is true.

定义操作数之间的关系，其中如果所有操作数都为假，则结果为真，如果至少有一个操作数为真，则为假。

A constraint whose objective is to ensure satisfaction of a code compliance provision.

一种约束，其目标是确保代码遵从性规定的满足。

A constraint whose objective is to identify an agreement that code compliance requirements (the waiver) will not be enforced.

一种约束，其目标是确定代码遵从性需求(放弃)不会被强制的协议。

A constraint whose objective is to synchronize data with an external source such as a file

一种约束，其目标是将数据与外部源(如文件)同步

A constraint whose objective is to ensure satisfaction of a health and safety provision.

目的是确保满足健康和安全规定的约束。

A constraint whose objective is to resolve a conflict such as merging data from multiple sources.

目标是解决冲突的约束，例如合并来自多个源的数据。

A constraint whose objective is to ensure data conforms to a model view definition.

一种约束，其目标是确保数据符合模型视图定义。

A constraint whose objective is to calculate a value based on other referenced values.

一种约束，其目标是根据其他参考值计算一个值。

A constraint whose objective is to ensure satisfaction of a project requirement provision.

目标是确保满足项目需求规定的约束。

A constraint whose objective is to ensure satisfaction of a specification provision.

目标是确保规范规定的满足的约束。

A constraint whose objective is to indicate a limiting value beyond which the condition of an object requires a particular form of attention.

一种约束，其目标是指出一个限制值，超过这个限制值，一个对象的条件需要一种特殊形式的注意。

A human-readable name to be used for the constraint.

• 用于约束的人类可读的名称。

A human-readable description that may apply additional information about a constraint.

• 一个人类可读的描述，它可以应用关于约束的附加信息。

Enumeration that qualifies the type of constraint.

• 限定约束类型的枚举。

Any source material, such as a code or standard, from which the constraint originated.

• 约束产生的任何源材料，如代码或标准。

Person and/or organization that has created the constraint.

• 创建约束的人员和/或组织。

Time when information specifying the constraint instance was created.

• 创建指定约束实例的信息的时间。

Allows for specification of user defined grade of the constraint beyond the enumeration values (hard, soft, advisory) provided by ConstraintGrade attribute of type IfcConstraintEnum. When a value is provided for attribute UserDefinedGrade in parallel the attribute ConstraintGrade shall have enumeration value USERDEFINED.

• 允许指定用户定义的约束等级，而不是由类型为IfcConstraintEnum的ConstraintGrade属性提供的枚举值(硬的、软的、建议的)。当为属性UserDefinedGrade同时提供一个值时，属性ConstraintGrade应该具有枚举值USERDEFINED。

Reference to an external references, e.g. library, classification, or document information, that are associated to the constraint.

• 对外部引用的引用，例如与约束相关联的库、分类或文档信息。

Reference to the properties to which the constraint is applied.

• 引用应用约束的属性。

Enumeration that identifies the type of benchmark data.

• 枚举，用于标识基准测试数据的类型。

Reference source for data values. If DataValue refers to an IfcTable, this attribute identifies the relevent column identified by IfcTableColumn.Identifier.

• 数据值的参考源。如果DataValue指向一个IfcTable，这个属性标识了由IfcTableColumn.Identifier标识的相关列。

The value to be compared on associated objects. A null value indicates comparison to null.

• 在关联对象上进行比较的值。空值表示与空值的比较。

Optional path to an attribute to be constrained on associated objects. If provided, the metric may be validated by resolving the path to the current value on associated object(s), and comparing such value with DataValue according to the Benchmark.

• 关联对象上要约束的属性的可选路径。如果提供，则可以通过解析关联对象上当前值的路径来验证度量，并根据基准将该值与DataValue进行比较。

A list of nested constraints.

• 嵌套约束的列表。

Enumeration that identifies the logical type of aggregation for the benchmark metrics.

• 枚举，该枚举标识基准度量的聚合逻辑类型。

Enumeration that qualifies the type of objective constraint.

• 限定目标约束类型的枚举。

A user defined value that qualifies the type of objective constraint when ObjectiveQualifier attribute of type IfcObjectiveEnum has value USERDEFINED.

• 当IfcObjectiveEnum类型的ObjectiveQualifier属性值为USERDEFINED时，用于限定目标约束类型的用户定义值。

The attribute UserDefinedQualifier must be asserted when the value of the ObjectiveQualifier is set to USERDEFINED.

• 当ObjectiveQualifier的值设置为USERDEFINED时，UserDefinedQualifier属性必须被断言。

Optional identifier of the entity or type such as 'IfcMaterialLayerSet'. For entity, type, or select-based references within a collection, this resolves the reference to such type. If omitted, the type is assumed to be the same as the declared referencing attribute.

• 实体或类型的可选标识符，如“IfcMaterialLayerSet”。对于集合中的实体、类型或基于选择的引用，这会将引用解析为此类类型。如果省略，则假定该类型与声明的引用属性相同。

EXAMPLE  
IfcRelAssociatesMaterial.
RelatingMaterial may be resolved to 
IfcMaterialLayerSet.

• IfcRelAssociatesMaterial示例。相关材料可以被解析为IfcMaterialLayerSet。

Optionally identifies a direct or inverse attribute within an entity such as 'MaterialLayers'. If TypeIdentifier is specified and refers to an entity, the attribute must exist within the referenced entity. A null value indicates a reference to the type or entity itself, such as for indicating that the type of a value must match a specified constraint.

• 可以选择在实体(如“MaterialLayers”)中标识一个直接或相反的属性。如果指定了TypeIdentifier并引用了一个实体，则该属性必须存在于引用的实体中。空值指示对类型或实体本身的引用，例如指示值的类型必须匹配指定的约束。

Optionally identifies an instance within a collection according to name. If the instance has an attribute called 'Name', such attribute is used for comparison; otherwise the first STRING-based attribute of the entity is used.

• 可选地根据名称标识集合中的实例。如果实例有一个名为'Name'的属性，则使用该属性进行比较;否则使用实体的第一个基于字符串的属性。

EXAMPLE  
IfcRoot-based entities such as 
IfcPropertySet use the 
Name attribute; 
IfcRepresentation entities use the 
RepresentationIdentifier attribute.

基于ifroot的实体，如IfcPropertySet，使用Name属性;IfcRepresentation实体使用具象标识符属性。

Optionally identifies an instance within a collection according to position starting at 1. For referencing single-level collections, this attribute contains a single member; for referencing multi-level collections, then this LIST attribute contains multiple members starting from the outer-most index.

• 可以根据从1开始的位置在集合中标识一个实例。对于引用单级别集合，此属性包含单个成员;如果要引用多级集合，则LIST属性包含从最外层索引开始的多个成员。

Optional reference to an inner value for ENTITY, SELECT, SET, or LIST attributes. A path may be formed by linking IfcReference instances together.

• 对ENTITY、SELECT、SET或LIST属性的内部值的可选引用。路径可以通过将IfcReference实例链接在一起而形成。

EXAMPLE  A material layer thickness may be referenced using several instances: #1=IFCREFERENCE($,'IfcSlab','HasAssociations',#2); #2=IFCREFERENCE($,'IfcMaterialLayerSet','MaterialLayers',#3); #3=IFCREFERENCE('Core','IfcMaterialLayer','LayerThickness',$);

• 一个材料层的厚度可以用几个实例来引用:#1=IFCREFERENCE($，'IfcSlab'，'HasAssociations'，#2);# 2 = IFCREFERENCE($、“IfcMaterialLayerSet”、“MaterialLayers”,# 3);# 3 = IFCREFERENCE(“核心”、“IfcMaterialLayer”、“LayerThickness”,$);

A name used to identify or qualify the relationship.

• 用于标识或限定关系的名称。

A description that may apply additional information about the relationship.

• 可以应用有关关系的附加信息的描述。

The constraint that is to be related.

• 相关的约束条件。

The properties to which a constraint is to be related.

• 约束要关联到的属性。