空引數 的英文怎麼說
中文拼音 [kōngyǐnshǔ]
空引數
英文
empty argument-
Spatial data - sets for geographical referencing - specification for a street gazetteer
地理定位用空間數據集.街道地名索引規范Spatial data - sets for geographical referencing - specification for a land and property gazetteer
地理定位用空間數據集.地產地名索引規范The system stores spatial data and characteristic data into central database, and provides services to users in server / client mode. as the research emphases of this thesis, several key sub - systems are designed and realized. the digital map input and maintenance subsystem performs format conversion, editing and updating of spatial data ; the rail - track video playing subsystem uses video recording as reference data, then plays, inquires and traces the corresponding frames in synchronous to the scaled mileage, realizing the query of the active picture frames ; the digital map query subsystem fulfills the map query, preview and spelling of digital map orthograph
其中，地形圖輸入與維護實現了數字地圖的格式轉換、編輯處理以及空間數據的更新操作，解決了不同格式空間數據的互相轉換問題；線路錄象播放將線路錄像數據作為系統的一種索引數據，活動影像的畫面與里程相對應，實現了基於線路錄像的播放、查詢和檢索的功能，實現了基於活動畫面的查詢檢索功能；數字地圖子系統完成了圖形查詢、數字地圖與線路正射圖像瀏覽、圖幅拼接等功能。In this thesis hydraulic experimental studies and theoretical analyses on the vortex - flow drop shaft were conduced and the following results were accomplished : ( 1 ) in the model test some hydraulic characteristics including the shape of air core in the center of the drop shaft, the radial distribution of water flow velocity and the distribution of pressure on the wall of the drop shaft were measured under the condition of high water head above 250m and large discharge above 1400m3 / s. ( 2 ) a kind of computational method for the spiral water flow in the air core region of drop shaft was discussed and applied and the results agree the experimental data well. ( 3 ) the total ratio of energy dissipation in the drop shaft can reach 90 % and the energy dissipation in every region was discussed quantitatively
本文通過試驗研究與理論分析對旋流式豎井泄洪洞應用於高水頭、大泄流量情況時存在的一些水力學問題進行了研究和探討，取得以下主要成果：一、結合小灣工程導流洞改建，對高水頭（ 252m ） 、大泄流量（ 1400m ~ 3 s ）條件下旋流式豎井中的水流運動特徵進行了比較全面的測量，包括空腔形態、徑向流速分佈及井壁壓強等；二、提出了豎井空腔段螺旋水流水力計算方法，其計算結果與實測值吻合良好；三、利用試驗與計算結果，對旋流式豎井的消能機理進行了探討，對豎井各部分的消能能力有了總體認識；四、對豎井下部消力井的合理井深進行了優化試驗研究，發現消力井合理深度為0 . 9d左右；五、通過試驗研究，歸納出豎井水流總摻氣量估算方法，為導流洞排氣方案的設計提供了參考依據；六、在高水頭、大流量條件下，豎井空腔段下部流速很高，盡管水流螺旋運動引起的離心力可以確保井壁壓強保持正壓，但空化數依然較低，因此豎井的空化空蝕始終是工程界關注的重大問題。Much of what is left of its industry is in high - tech or research - based fields such as aerospace engines and pharmaceuticals, where its world - class firms are more than holding their own
該國現有行業大多數集中在高科技或研究領域，諸如航空引擎以及制藥業，這些世界級的公司沒有滿足只是在國內稱霸，還將觸角伸向了海外。Parameter cannot be a null reference nothing in visual basic, be empty, or contain a string with only blank characters
參數不能包含空引用（在visual basic中為nothing ）值，不能為空，也不能包含僅有空白字元的字元串。Key technologies of spatial data enginer based on multi - data source
多數據源空間數據引擎關鍵技術問題研究14 guttman a. r - trees : a dynamic index structure for spatial searching. in proc
上述機制在數據組織時並不需要對空間數據對象進行索引。Firstly, the notion of the form as a = > b [ s %, c % ] is researched and some algorithms are discussed. an algorithm named a progressive refinement approach to spatial data mining is discussed in detail. and a new thought of mining spatial association rule based on spatial data cube is brought forward
闡述了a = > b [ s ， c ]形式的空間關聯規則的基本概念和演算法，詳細研究了一種逐步求精的空間關聯規則挖掘演算法的實現；提出一種基於空間數據立方體的空間關聯規則挖掘的新思路；將空間統計分析引入空間關聯規則挖掘領域，研究了空間權重矩陣、空間自相關、空間關聯等的度量函數，並利用空間統計分析技術發現空間相關關系和空間關聯規則。If a particular argument has no required custom modifiers, specify a null reference nothing in visual basic instead of an array of types
如果某個特定參數沒有必需的自定義修飾符，請指定空引用（在visual basic中為nothing ） ，而不要指定類型數組。If a particular argument has no optional custom modifiers, specify a null reference nothing in visual basic instead of an array of types
如果某個特定參數沒有可選的自定義修飾符，請指定空引用（在visual basic中為nothing ） ，而不要指定類型數組。The function and systematic structural design of spatial database engine for rdbms
的空間數據引擎體系結構框架設計If the value in the key parameter is not found, returns a null reference nothing in visual basic
如果未找到鍵參數中的值，則返回空引用（在visual basic中為nothing ） 。For an explicit reference conversion to be successful, the source value must be a null reference nothing in visual basic, or the object type referenced by the source argument must be convertible to the destination type by an implicit reference conversion
為使顯式引用轉換成功進行，源值必須為空引用（在visual basic中為nothing ） ，或者源參數引用的對象類型必須可以通過隱式引用轉換來轉換為目標類型。Gets or sets a value indicating whether empty string values are converted to a null reference nothing in visual basic when the field values are retrieved from the data source
獲取或設置一個值，該值指示在從數據源檢索欄位值時，是否將空字元串（ " ）值轉換為空引用（在visual basic中為nothing ） 。Parameter is not a null reference nothing in visual basic and is not an instance of the same class as the current permission
參數不為空引用（在visual basic中為nothing ） ，並且不是與當前權限屬于相同類的實例。Spatial index is a indispensable part of spatial database, and can dramatically improve efficiency when doing a spatial query
空間索引作為空間數據庫中的重要組成部分，可以加快對空間對象的檢索。Aim at the characters of spatial data access control, the concept of spatial region access control based on spatial index was proposed
摘要針對空間數據的訪問控制的特點，提出了基於空間索引的區域訪問控制概念。Most the databases can support non - structure data ; so both spatial data and attribute data can be stored in database. when spatial data is stored and managed by dbms, it can be indexed, queried and analyzed expediently
這樣可以將空間數據和屬性數據有機地集成起來，實現有效的存儲和管理在此基礎上，實現便利的空間索引、查詢和各種分析操作。The first generation spatial analysis database system, sadbs, uses " realms " as expression base of spatial data. it adopts discrete integer coordinate system to solve topological error in spatial database. it also uses multi - index data organization and plane - sweep algorithm, which improve the performance of spatial analysis operations
第一代空間分析數據庫系統sadbs使用realms作為空間數據的表示基礎，它利用離散化的整數坐標系統，解決了空間數據庫的拓撲誤差問題；使用多索引的數據組織方法，引入平面掃描演算法，提高了空間分析操作的性能。分享友人