国产在热线精品视频99国产一二,办公室高潮秘书疯狂呻吟视频,蜜臀av国产一区二区三区,成人丝袜激情一区二区,粉嫩虎白女18p

  咨詢電話:13925432838

佛山市南海厚博電子技術有限公司

主營(ying):電(dian)動工具電(dian)阻片,發熱片,陶瓷(ci)板,線路(lu)板

商盟客服

您好,歡(huan)(huan)迎蒞(li)臨厚博電子,歡(huan)(huan)迎咨詢(xun)...

先生:

印刷碳阻片多少錢-田東印刷碳阻片-厚博電子哪家好(查看)

||| 產品編號:588386088                    更新時間:2024-12-09
佛山市南海厚博電子技術有限公司
  • 主(zhu)營業務(wu):電動工具電阻片,發熱片,陶瓷板,線路板
  • 公司官網:
  • 公(gong)司地(di)址:佛山市南海區丹灶鎮新農社區青塘大道5號
業務(wu)熱(re)線: 13925432838 (羅石(shi)華 先生)     
  • 供貨總量 : 不限
  • 價格說明 : 議定
  • 包裝說明 : 不限
  • 物流說明 : 貨運及物流
  • 交貨說明 : 按訂單
企業視頻展播,請點擊播放
視頻作者:佛山市南海厚博電子技術有限公司

集成電路是什么材質

集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路是(shi)(shi)(shi)現(xian)代電(dian)(dian)(dian)(dian)子技(ji)術的(de)(de)(de)(de),其(qi)(qi)(qi)制(zhi)(zhi)(zhi)(zhi)造涉及多種關鍵材(cai)(cai)(cai)(cai)料(liao)(liao)。其(qi)(qi)(qi)中(zhong),硅(gui)(gui)是(shi)(shi)(shi)集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路制(zhi)(zhi)(zhi)(zhi)造的(de)(de)(de)(de)主(zhu)要(yao)材(cai)(cai)(cai)(cai)料(liao)(liao)。硅(gui)(gui)具(ju)(ju)(ju)有(you)優異的(de)(de)(de)(de)半導體性(xing)(xing)(xing)能(neng)(neng),可以通過(guo)摻雜(za)磷(lin)、硼等元素來(lai)改(gai)變其(qi)(qi)(qi)導電(dian)(dian)(dian)(dian)性(xing)(xing)(xing),這使得(de)(de)硅(gui)(gui)成(cheng)(cheng)(cheng)為(wei)制(zhi)(zhi)(zhi)(zhi)造晶體管、二極(ji)管等電(dian)(dian)(dian)(dian)子器件的(de)(de)(de)(de)理想(xiang)選擇。此(ci)外,印刷碳(tan)阻(zu)片(pian)工(gong)廠,硅(gui)(gui)基集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路具(ju)(ju)(ju)有(you)成(cheng)(cheng)(cheng)熟的(de)(de)(de)(de)制(zhi)(zhi)(zhi)(zhi)造工(gong)藝和(he)較低(di)的(de)(de)(de)(de)成(cheng)(cheng)(cheng)本,因此(ci)得(de)(de)到了(le)廣(guang)泛應(ying)用(yong)(yong)。在(zai)集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路的(de)(de)(de)(de)制(zhi)(zhi)(zhi)(zhi)造過(guo)程(cheng)中(zhong),硅(gui)(gui)晶圓(yuan)是(shi)(shi)(shi)基礎(chu)材(cai)(cai)(cai)(cai)料(liao)(liao)。硅(gui)(gui)晶圓(yuan)是(shi)(shi)(shi)一種由高(gao)純度硅(gui)(gui)制(zhi)(zhi)(zhi)(zhi)成(cheng)(cheng)(cheng)的(de)(de)(de)(de)圓(yuan)形薄片(pian),其(qi)(qi)(qi)表面涂有(you)光刻膠,用(yong)(yong)于制(zhi)(zhi)(zhi)(zhi)造集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路上的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)路圖案。由于硅(gui)(gui)晶圓(yuan)的(de)(de)(de)(de)純度極(ji)高(gao),摻雜(za)元素含量極(ji)低(di),印刷碳(tan)阻(zu)片(pian)多少錢,因此(ci)非常(chang)適合作(zuo)(zuo)為(wei)集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路的(de)(de)(de)(de)制(zhi)(zhi)(zhi)(zhi)造材(cai)(cai)(cai)(cai)料(liao)(liao)。除了(le)硅(gui)(gui)之外,金屬也(ye)是(shi)(shi)(shi)集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路制(zhi)(zhi)(zhi)(zhi)造中(zhong)的(de)(de)(de)(de)重要(yao)材(cai)(cai)(cai)(cai)料(liao)(liao)。例如(ru),鋁和(he)銅(tong)在(zai)集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路中(zhong)發揮(hui)著關鍵作(zuo)(zuo)用(yong)(yong)。鋁能(neng)(neng)夠(gou)承受高(gao)溫,并具(ju)(ju)(ju)有(you)良好的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)導率(lv)和(he)可焊性(xing)(xing)(xing),因此(ci)在(zai)集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路中(zhong)廣(guang)泛應(ying)用(yong)(yong)。而(er)銅(tong)則(ze)因其(qi)(qi)(qi)低(di)電(dian)(dian)(dian)(dian)阻(zu)、高(gao)強度和(he)良好的(de)(de)(de)(de)耐腐(fu)蝕性(xing)(xing)(xing),在(zai)現(xian)代集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路的(de)(de)(de)(de)制(zhi)(zhi)(zhi)(zhi)造中(zhong)得(de)(de)到了(le)廣(guang)泛應(ying)用(yong)(yong),主(zhu)要(yao)用(yong)(yong)于制(zhi)(zhi)(zhi)(zhi)造集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路中(zhong)的(de)(de)(de)(de)導線(xian)和(he)焊盤。此(ci)外,還有(you)一些(xie)其(qi)(qi)(qi)他材(cai)(cai)(cai)(cai)料(liao)(liao)也(ye)用(yong)(yong)于集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路的(de)(de)(de)(de)制(zhi)(zhi)(zhi)(zhi)造。例如(ru),氮(dan)化硅(gui)(gui)和(he)氧化硅(gui)(gui)是(shi)(shi)(shi)具(ju)(ju)(ju)有(you)優良絕(jue)緣(yuan)性(xing)(xing)(xing)能(neng)(neng)的(de)(de)(de)(de)材(cai)(cai)(cai)(cai)料(liao)(liao),可以用(yong)(yong)于制(zhi)(zhi)(zhi)(zhi)造集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路中(zhong)的(de)(de)(de)(de)絕(jue)緣(yuan)層和(he)介質(zhi)層。金則(ze)因其(qi)(qi)(qi)優良的(de)(de)(de)(de)導電(dian)(dian)(dian)(dian)性(xing)(xing)(xing)能(neng)(neng)和(he)性(xing)(xing)(xing)能(neng)(neng),被(bei)用(yong)(yong)于制(zhi)(zhi)(zhi)(zhi)造集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路中(zhong)的(de)(de)(de)(de)焊盤和(he)接點。綜上所(suo)述,集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路的(de)(de)(de)(de)制(zhi)(zhi)(zhi)(zhi)造涉及多種關鍵材(cai)(cai)(cai)(cai)料(liao)(liao),其(qi)(qi)(qi)中(zhong)硅(gui)(gui)和(he)金屬是(shi)(shi)(shi)的(de)(de)(de)(de)材(cai)(cai)(cai)(cai)料(liao)(liao)。這些(xie)材(cai)(cai)(cai)(cai)料(liao)(liao)的(de)(de)(de)(de)選擇和(he)應(ying)用(yong)(yong)對集(ji)(ji)(ji)(ji)成(cheng)(cheng)(cheng)電(dian)(dian)(dian)(dian)路的(de)(de)(de)(de)性(xing)(xing)(xing)能(neng)(neng)和(he)穩定(ding)性(xing)(xing)(xing)起著至關重要(yao)的(de)(de)(de)(de)作(zuo)(zuo)用(yong)(yong)。

PCB線(xian)路(lu)(lu)(lu)板(ban),全稱為印制電(dian)(dian)(dian)路(lu)(lu)(lu)板(ban)(Printed Circuit Board),是電(dian)(dian)(dian)子(zi)(zi)設備的(de)(de)(de)(de)組成(cheng)(cheng)部分,扮演著連(lian)接(jie)和支撐(cheng)電(dian)(dian)(dian)子(zi)(zi)元(yuan)件(jian)(jian)(jian)(jian)的(de)(de)(de)(de)關(guan)鍵角色。以(yi)下(xia)是對PCB線(xian)路(lu)(lu)(lu)板(ban)的(de)(de)(de)(de)詳(xiang)細(xi)介紹:一、定(ding)義(yi)與(yu)功能PCB線(xian)路(lu)(lu)(lu)板(ban)是通(tong)過電(dian)(dian)(dian)子(zi)(zi)印刷術制作的(de)(de)(de)(de)基(ji)板(ban),用(yong)于支持(chi)和連(lian)接(jie)電(dian)(dian)(dian)子(zi)(zi)組件(jian)(jian)(jian)(jian)。它主要(yao)由非導(dao)電(dian)(dian)(dian)的(de)(de)(de)(de)基(ji)材(如玻璃纖維、環(huan)氧樹脂等)和導(dao)電(dian)(dian)(dian)層(ceng)(通(tong)常是銅箔)組成(cheng)(cheng)。PCB的(de)(de)(de)(de)主要(yao)功能包括:電(dian)(dian)(dian)氣連(lian)接(jie):通(tong)過導(dao)電(dian)(dian)(dian)層(ceng)上的(de)(de)(de)(de)金(jin)屬線(xian)路(lu)(lu)(lu)將電(dian)(dian)(dian)子(zi)(zi)元(yuan)件(jian)(jian)(jian)(jian)互相連(lian)接(jie),實(shi)現電(dian)(dian)(dian)路(lu)(lu)(lu)的(de)(de)(de)(de)導(dao)通(tong)和傳(chuan)輸(shu)(shu)(shu)。機械(xie)支撐(cheng):為電(dian)(dian)(dian)子(zi)(zi)元(yuan)件(jian)(jian)(jian)(jian)提供穩(wen)定(ding)的(de)(de)(de)(de)機械(xie)支撐(cheng),確(que)(que)保元(yuan)件(jian)(jian)(jian)(jian)的(de)(de)(de)(de)相對位(wei)置固定(ding)并保護元(yuan)件(jian)(jian)(jian)(jian)免(mian)受外(wai)界環(huan)境的(de)(de)(de)(de)影響。信(xin)(xin)號(hao)(hao)(hao)傳(chuan)輸(shu)(shu)(shu):PCB上的(de)(de)(de)(de)金(jin)屬線(xian)路(lu)(lu)(lu)還負(fu)責傳(chuan)輸(shu)(shu)(shu)電(dian)(dian)(dian)子(zi)(zi)元(yuan)件(jian)(jian)(jian)(jian)之間的(de)(de)(de)(de)信(xin)(xin)號(hao)(hao)(hao),包括電(dian)(dian)(dian)力、模擬信(xin)(xin)號(hao)(hao)(hao)和數字信(xin)(xin)號(hao)(hao)(hao)。電(dian)(dian)(dian)源(yuan)分配(pei):將電(dian)(dian)(dian)源(yuan)與(yu)各個電(dian)(dian)(dian)子(zi)(zi)組件(jian)(jian)(jian)(jian)連(lian)接(jie)起來,以(yi)滿足(zu)電(dian)(dian)(dian)子(zi)(zi)組件(jian)(jian)(jian)(jian)的(de)(de)(de)(de)工作電(dian)(dian)(dian)壓和電(dian)(dian)(dian)流需求。信(xin)(xin)號(hao)(hao)(hao)隔離(li):避免(mian)不同電(dian)(dian)(dian)子(zi)(zi)元(yuan)件(jian)(jian)(jian)(jian)之間的(de)(de)(de)(de)信(xin)(xin)號(hao)(hao)(hao)相互干擾,確(que)(que)保電(dian)(dian)(dian)路(lu)(lu)(lu)的(de)(de)(de)(de)穩(wen)定(ding)性(xing)和可(ke)靠(kao)性(xing)。

油(you)(you)(you)門(men)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)在(zai)汽(qi)車(che)(che)電(dian)(dian)子控(kong)制(zhi)(zhi)系統中(zhong)扮(ban)演著至關重(zhong)要的(de)(de)(de)(de)角色。它是油(you)(you)(you)門(men)踏(ta)板(ban)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)的(de)(de)(de)(de)一(yi)部分,主要作(zuo)(zuo)(zuo)用(yong)是將節氣門(men)的(de)(de)(de)(de)開度(du)位(wei)置(zhi)(zhi)(zhi)和大小(xiao)轉(zhuan)化為(wei)(wei)電(dian)(dian)信(xin)號(hao),印(yin)刷碳阻(zu)(zu)(zu)片(pian)(pian)(pian)價錢,進而傳(chuan)(chuan)遞給汽(qi)車(che)(che)的(de)(de)(de)(de)ECU(電(dian)(dian)子控(kong)制(zhi)(zhi)單元)。具體(ti)來說,當駕駛(shi)(shi)員(yuan)踩下油(you)(you)(you)門(men)踏(ta)板(ban)時(shi),油(you)(you)(you)門(men)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)會根據踏(ta)板(ban)的(de)(de)(de)(de)移動距離和速度(du),改變自身的(de)(de)(de)(de)電(dian)(dian)阻(zu)(zu)(zu)值,從(cong)而生成相應的(de)(de)(de)(de)電(dian)(dian)信(xin)號(hao)。這(zhe)些(xie)(xie)電(dian)(dian)信(xin)號(hao)隨(sui)后被傳(chuan)(chuan)送到ECU,ECU通過(guo)對這(zhe)些(xie)(xie)信(xin)號(hao)的(de)(de)(de)(de)綜(zong)合處理(li),可以(yi)地控(kong)制(zhi)(zhi)發(fa)動機(ji)的(de)(de)(de)(de)燃油(you)(you)(you)噴射量、點火時(shi)機(ji)等(deng)參數,從(cong)而實現(xian)(xian)對車(che)(che)輛(liang)動力輸(shu)出(chu)的(de)(de)(de)(de)控(kong)制(zhi)(zhi)。油(you)(you)(you)門(men)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)的(de)(de)(de)(de)性(xing)能(neng)直接影(ying)響到ECU對發(fa)動機(ji)的(de)(de)(de)(de)控(kong)制(zhi)(zhi)精(jing)度(du)。如果電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)出(chu)現(xian)(xian)故(gu)障或老化,可能(neng)會導致傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)輸(shu)出(chu)的(de)(de)(de)(de)電(dian)(dian)信(xin)號(hao)失真或不穩定(ding),進而影(ying)響到發(fa)動機(ji)的(de)(de)(de)(de)工(gong)作(zuo)(zuo)(zuo)狀態,甚至可能(neng)引(yin)發(fa)車(che)(che)輛(liang)行(xing)駛(shi)(shi)中(zhong)的(de)(de)(de)(de)安全隱患。因此,定(ding)期檢查和更(geng)(geng)換(huan)(huan)油(you)(you)(you)門(men)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)是確(que)保汽(qi)車(che)(che)正常(chang)運行(xing)和行(xing)駛(shi)(shi)安全的(de)(de)(de)(de)重(zhong)要措施之一(yi)。同時(shi),隨(sui)著汽(qi)車(che)(che)電(dian)(dian)子技術的(de)(de)(de)(de)不斷發(fa)展,油(you)(you)(you)門(men)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)也在(zai)不斷更(geng)(geng)新換(huan)(huan)代,以(yi)適應更(geng)(geng)、更(geng)(geng)的(de)(de)(de)(de)發(fa)動機(ji)控(kong)制(zhi)(zhi)需(xu)求(qiu)。綜(zong)上所述,油(you)(you)(you)門(men)位(wei)置(zhi)(zhi)(zhi)傳(chuan)(chuan)感(gan)(gan)(gan)器(qi)(qi)電(dian)(dian)阻(zu)(zu)(zu)片(pian)(pian)(pian)在(zai)汽(qi)車(che)(che)電(dian)(dian)子控(kong)制(zhi)(zhi)系統中(zhong)具有(you)的(de)(de)(de)(de)作(zuo)(zuo)(zuo)用(yong),田東印(yin)刷碳阻(zu)(zu)(zu)片(pian)(pian)(pian),它通過(guo)將駕駛(shi)(shi)員(yuan)的(de)(de)(de)(de)油(you)(you)(you)門(men)操作(zuo)(zuo)(zuo)轉(zhuan)化為(wei)(wei)電(dian)(dian)信(xin)號(hao),實現(xian)(xian)了對發(fa)動機(ji)動力輸(shu)出(chu)的(de)(de)(de)(de)控(kong)制(zhi)(zhi),從(cong)而提高了車(che)(che)輛(liang)的(de)(de)(de)(de)行(xing)駛(shi)(shi)性(xing)能(neng)和安全性(xing)。

印刷碳阻片多少錢-田東印刷碳阻片-厚博電子哪家好(查看)由佛山市南海厚博電子技術有限公司提供。“電動工具電阻片,發熱片,陶瓷板,線路板”選擇佛山市南海厚博電子技術有限公司,公司位于:佛山市南海區丹灶鎮新農社區青塘大道5號,多年來,厚博電子堅持為客戶提供好的服務,聯系人:羅石華。歡迎廣大新老客戶來電,來函,親臨指導,洽談業務。厚博電子期待成為您的長期合作伙伴!

溫馨提示:以上是關于印刷碳阻片多少錢-田東印刷碳阻片-厚博電子哪家好(查看)的詳細介紹,產品由佛山市南海厚博電子技術有限公司為您提供,如果您對佛山市南海厚博電子技術有限公司產品信息感興趣可以或者 ,您也可以查看更多與印刷線路板相關的產品!

免責聲明
? 本文僅代表作者個人觀點,本站未對其內容進行核實,請讀者僅做參考,如若文中涉及有違公德、觸犯法律的內容,一經發現,立即刪除,作者需自行承擔相應責任。涉及到版權或其他問題,請及時聯系我們 tousu@50835.cn
  • 羅石華先生
  • 手機:13925432838
  • 聯系我時務必告知是在天助網上看到的!

佛山市(shi)南海厚博電子(zi)技術有限公司(si)

|

地址:佛山(shan)市南海區丹灶(zao)鎮新農(nong)社區青塘大道(dao)5號

電話:13925432838傳真:0757-26262626

同行企業推薦:

免(mian)責聲明(ming):以上信(xin)息由會員自行(xing)(xing)提供(gong),內容的真實性(xing)(xing)、準(zhun)確性(xing)(xing)和(he)合法性(xing)(xing)由發布(bu)會員負責(ze),天助(zhu)(zhu)網(wang)(wang)對此(ci)不承擔(dan)任何責(ze)任。天助(zhu)(zhu)網(wang)(wang)不涉及用戶間因交易而產生的法律關系及法律糾紛, 糾紛由您自行(xing)(xing)協商解(jie)決。

風險(xian)提醒:本網(wang)(wang)站僅作為(wei)用戶(hu)尋找交易對(dui)(dui)象,就貨物和服務的交易進行協商,以及獲(huo)取各類與貿易相關(guan)的服務信息(xi)的平臺。為(wei)避(bi)免(mian)產生購買風險,建議(yi)您在購買相關(guan)產品前務必(bi) 確認(ren)供應商資質(zhi)及產品質(zhi)量。過低的價格、夸張的描(miao)述、私人銀行賬(zhang)戶(hu)等都有可能是虛(xu)假信息(xi),請采購商謹(jin)慎(shen)對(dui)(dui)待(dai),謹(jin)防欺(qi)詐,對(dui)(dui)于任何付款行為(wei)請您慎(shen)重抉擇!如您遇(yu)到欺(qi)詐 等不誠信行為(wei),請您立(li)即與天(tian)助(zhu)(zhu)網(wang)(wang)聯系,如查(cha)證(zheng)屬實,天(tian)助(zhu)(zhu)網(wang)(wang)會對(dui)(dui)該企業商鋪做注(zhu)銷處理,但天(tian)助(zhu)(zhu)網(wang)(wang)不對(dui)(dui)您因此(ci)造(zao)成的損(sun)失承擔責任!

聯(lian)系:tousu@50835.cn是處理侵權(quan)投訴的(de)專用(yong)郵箱,在(zai)您的(de)合法權(quan)益受到侵害時,歡(huan)迎您向(xiang)該郵箱發送郵件(jian),我們會在(zai)3個工作日(ri)內給您答復,感謝(xie)您對我們的(de)關(guan)注與(yu)支持!

商盟會員 第11年
  • 企業等級:商(shang)盟會員
  • 經營模式:生產加工
  • 所在地區:廣東 佛山
  • 聯系賣家:羅石華 先生(sheng)
  • 手機號碼:13925432838
  • 聯系電話:0757-85411768
  • 公司傳真:0757-26262626

企業相關導航

企業百科
企業推薦分類
企業云鋪

企業最新產品

按字母分類: A| B| C| D| E| F| G| H| I| J| K| L| M| N| O| P| Q| R| S| T| U| V| W| X| Y| Z| 0-9

增值電信業(ye)(ye)務經營許(xu)可證:粵(yue)(yue)B2-20191121         |         網站備(bei)案編號(hao):粵(yue)(yue)ICP備(bei)10200857號(hao)-23         |         高(gao)新(xin)技術企(qi)業(ye)(ye):GR201144200063         |         粵(yue)(yue)公網安備(bei) 44030302000351號(hao)

Copyright ? 2006-2025 深圳市(shi)天(tian)助(zhu)人和信息技術有限公司 版權所(suo)有 網(wang)站統(tong)計