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The Role of Japanese Direct Investment

The Role of Japanese Direct Investment
The Role of Japanese Direct Investment

This paper appears in Empirical Economics Letters, 11(6), 527-534. (2011)
U.S. Bilateral Trade Deficits with China and Japan:
The Role of Japanese Direct Investment
Sokchea Lim and Channary Khun?
Abstract: This paper argues that Japanese Foreign Direct Investment (FDI) in China plays a critical role in home and host country’s bilateral trade imbalances with the U.S. Using six cross-sectional panel data from 1981 to 2007, we find strong evidence in support of the role of Japanese FDI in mounting U.S.-China trade imbalance and in reducing deficit of U.S. trade with Japan. The results also indicate that the devaluation of Chinese Yuan does not affect its bilateral trade balance with the U.S. and there are mixed evidence in terms of the relationship between the Japanese Yen exchange rate and the U.S.-Japan trade deficit. The implication of these findings is that U.S. trade deficit is a macroeconomic problem which cannot be blamed on the exchange rate alone. Policies to attract and retain Japanese firms in the U.S. will help reduce its trade deficit in the long-run.
Keywords: Japanese Foreign Direct Investment, bilateral trade imbalance, devaluation of exchange rate.
?
Sokchea Lim and Channary Khun are PhD students of the Department of Economics, Southern Illinois University
Carbondale. We thank Kevin Sylwester and two anonymous referees for helpful comments on an earlier draft. All remaining errors are entirely ours.
Electronic copy available at: https://www.sodocs.net/doc/0c4701432.html,/abstract=2034479

I. Introduction
After its trade liberalization in the late 1970s, China’s exports of manufactures have expanded dramatically, leading to growing concern among developed and developing economies. The rapid rise of China’s trade surplus with the former and the competition of China’s exports with the latter have posed considerable concern on the respective economies. In 2006, China surpassed the U.S. as the world's largest exporter with total exports of manufactures amounting to 404 billion USD. This rapid growth of exports has provided China with an enormous trade surplus with the U.S., reaching 285 billion USD in 2008 (U.S. International Trade Commission). The upsurge of U.S. bilateral trade deficit with China, coupled with its enormous overall trade deficits, has triggered severe trade frictions between the two nations.
Starting from labor-intensive and increasingly shifting to high-tech sectors, the sustained upward trend of U.S. deficit on trade with China is closely akin to its trade relation with Japan since the 1970s. According to UN Comtrade, U.S. deficits on trade with Japan grew from a low level of about one billion USD in 1970 to a record high of over 92 billion USD in 2006, yet representing only about 37 percent of its deficit with China counterpart. Like China today, Japan had been under intense allegation of unfair trade practices and currency manipulation, leading to Voluntary Restraint and Plaza Agreement during the 1980s. However, the climax of U.S.-Japan trade tension has subsided with the U.S.’s attention diverted and policies targeted emerging economies, like China. This is not surprising given the enormous amount and rapid growth of U.S. trade imbalance with China relative to that with Japan. In fact, the share of U.S.-Japan trade deficit has shrunk steadily while that with China has been on the rapid rise (Figure 1).
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Electronic copy available at: https://www.sodocs.net/doc/0c4701432.html,/abstract=2034479

Figure 1: U.S. Trade Deficits as the Percentage of GDP and Overall Deficits
Sources: UN Comtrade, WDI, and U.S. International Trade Commission. Note: ROW stands for the rest of the world besides Japan and China.
The U.S.’s obsession in solving bilateral trade deficits with a specific partner has taken it far afield from the fundamental problems of overall trade deficits and underlying macroeconomic conditions at home. A simple macroeconomic theory suggests that if the total domestic production of goods and services in a country falls short of domestic spending, there is a demand for imports, thereby causing trade imbalances. That is, overall trade deficit is essentially a macroeconomic issue and cannot be resolved with trade policies. That is to say trade policies targeting particular industry or trading partner may only work to affect the composition of trade but not the aggregate balance. Thus, the U.S.’s trade policies intended to curb Japanese imports can only substitute away Japanese goods for goods from other foreign suppliers such as China, while leaving overall level of trade deficits unchanged.
However, at the country level, a question naturally arises as to why U.S. consumers seem to have shifted a bulk of their import demand from Japan to China, causing such a massive bilateral trade imbalance. There have been several empirical studies into the root causes of the U.S. trade deficit with China. Xu (2008) attributes the U.S.-China trade imbalance to the so-called China’s
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undervalued currency, which allegedly makes China’s exports artificially cheap in the international markets. This has given rise to intense pressures from the U.S. on China to revalue its currency. Klitgaard and Schiele (1997) identify high trade barriers, low labor costs, and illegal subsidies on the part of China as the factors causing the trade imbalance. On the other hand, Burke (2000) argues that the surge in the level of U.S. direct investment in China has substituted for U.S. exports to China while boosting China’s exports to the U.S., thereby deteriorating U.S. trade deficit. However, in the study of intra industry trade, Xing (2007) found no evidence in support of the significant relationship between U.S. direct investment in China and the growth of intra-industry trade between the U.S. and China.
In essence, earlier studies examine U.S. trade deficit with China per se without taking into account the possible substitution for U.S.-Japan trade imbalance, which may suggest other underlying factors at work. Indeed, it can be argued that the desire of Japanese firms to meet the U.S.’s import demand is so strong that the U.S.’s protectionist trade policies intended to reduce Japanese imports to some extent have induced Japanese firms to relocate their production facilities to China and export their products to the U.S. This is not at all contentious given the extensive acknowledgment of the export-oriented nature of Japanese FDI in the empirical studies, and the rapid accumulation of Japanese FDI in China for the last two decades. Following this line of argument, this paper is the first to ascribe the mounting U.S. bilateral trade imbalance with China and decreasing share of its trade deficits with Japan to the influx of Japanese FDI into China.
The paper proceeds as follows: Section 2 provides an overview of the U.S.’s bilateral trade deficits with China and Japan and examines the natures of Japanese FDI in China. In the third
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section, we present econometric models to test the effects of Japanese direct investment on host and home country’s bilateral trade imbalances with the U.S. Finally, the empirical evidence and policy implications are laid out in Section 4 and 5, respectively.
II. Overview of U.S. Bilateral Trade Deficit and Japanese FDI in China
Although the gap of U.S. trade deficits has slightly narrowed as the severe recession since late 2007 has reduced demand for imports, the concern of the deficits is far from over given the enormous amount accumulated for the last three decades. In 1960, the U.S. was the world's leading exporter with trade surplus of over three billion USD (U.S. Census Bureau). However, since the 1970s it has experienced a deteriorating balance of trade and a dynamic shift in the composition of trade with its trading partners, China and Japan. Particularly, between 1978 and 2008, its overall trade deficit in goods has rapidly soared from approximately 40 billion USD to over 860 billion USD, about six percent of its GDP. This is a striking over twenty-fold increase in three decades.
Historically, the U.S. and Japan were major trading partners and their bilateral trade has been for the most part characterized by the imbalanced trade in favor of Japan. In 1981, the amount of their trade deficit in goods accounted for almost half of U.S. overall trade deficits, leading to serious trade tensions between the two nations. However, from 1990, the amount of U.S. trade imbalance with Japan has only expanded slowly while the share has rapidly declined, accounting for less than 10 percent by the end of 2008 (Figure 1). This is largely the result of increasing trade restrictions on the part of the U.S. and partly of their greater trade integration with other Asian countries and their neighbors.
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For a while after China embarked on far-reaching economic reforms in the late 1970s, the U.S. enjoyed a modest trade surplus with China. However, in less than a decade, China has emerged as one of the fastest export-led growth economy, with annual export growth averaging 13 percent since 1979 (World Development Indicators). At the end of the 1980s, U.S. exports to China began to lag behind its imports, leading to rapid surge of its bilateral trade deficits with China in the following decades. By 2008, U.S. trade deficit in goods with China has reached a record high of 285 billion USD, representing over 30 percent of its total trade deficits. It is noteworthy that China’s rapid trade expansion can be attributed to its role as the final assembly platform for other Asian countries’ exports to the West. Japan, in particular, has been one of the nations actively involved in such practices partly due to the discriminatory trade practices Japanese exporters face in the U.S. market.
The fact that Japan has used China as the assembly and production platform so as to serve the U.S. market has been made possible through the establishment of a network of subsidiaries in China. Japanese multinational enterprises (MNEs) seek to take advantages of the low production costs in China, coupled with their superior technology, brand name recognition and global distribution network, to increase their global competitiveness (Xing, 2006). That is the nature of Japanese FDI is to exploit comparative advantages in developing countries to enhance its export competitiveness (Kojima, 1978). Since the late 1980s, Japan has been one of the major sources of foreign direct investment in manufacturing sectors in China. Japanese direct investment in China has increased from almost zero in 1981 to over 40 billion USD in 2008 (Figure 2). The motives of Japanese FDI in China have important implications for the home and host country’s international trade with a major trading partner such as the U.S.
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Figure 2: Cumulative Japanese FDI in Chinese Manufacturing Sectors
Sources: Ministry of Finance, Japan.
The aggregate data may not disclose the whole story. While the U.S. ran overall trade deficits with both Japan and China, it actually had trade surpluses with both partners in some sectors. The bilateral trade imbalance between the U.S. and Japan was in the U.S’s favor in such sectors as Food and Live Animals combined with Beverage and Tobacco (SITC 0 & 1); Crude Materials, Inedible, Except Fuels (SITC 2); Mineral Fuels, Lubricants and Related Materials (SITC 3); and for most periods Chemicals and Related Products (SITC 5). On the other hand, U.S. trade surpluses with China were prominent in Crude Materials, Inedible, Except Fuels and to some extent in Chemicals and Related Products. These sectors are more of the primary products and the size of the surpluses was quite modest, with the rapid soar of U.S. trade surplus with China in Crude Materials, Inedible, Except Fuels, reaching approximately 18 billion USD in 2008 (Figure 3).
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Figure 3: U.S. Sectoral Trade Deficits as the Percentage of Sectoral GDP
Food & Live Animals
Crude Materials, Inedible, except Fuels
3
0 81 84 87 90 93 96 99 02 05
0 81 -3 84 87 90 93 96 99 02 05
-3
-6
-6
-9
-9
-12
-12
Mineral Fuels, Lubricants & Related Materials
Chemicals & Related Products, N.E.S.
6
1
3
0 81 84 87 90 93 96 99 02 05
0 81 -3 84 87 90 93 96 99 02 05
-1
-2
-6
-3
-9
-4
Manufactured Goods Classified Chiefly by Material
30 16 24 12 18 8 12 4 6 0 81 -4 84 87 90 93 96 99 02 05 -6 0 81 84
Machinery and Transport Equipment
87
90
93
96
99
02
05
Sources: UN Comtrade, U.S. International Trade Commission, Bureau of Economic Analysis, and Ministry of Finance, Japan. Note: Positive figures represent trade deficits, while negative figures indicate trade surpluses.
___ U.S.-CHN Deficit
___U.S.-JPN Deficit
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SITC 6, corresponding to Manufactured Goods Classified Chiefly by Materials, and SITC 7, representing Machinery and Transportation Equipment, are the two sectors that the U.S. consistently ran a substantial amount of trade deficits with the two nations. The most outstanding in terms of size and growth of U.S. bilateral trade deficit is SITC 7. The deficit with China in this sector alone accounted for almost 45 percent of their bilateral trade imbalance in 2008. This reflects the fact that the most drastic increases in exports from China to the U.S in the past decade have been in high-tech sectors, such as office machinery and electrical equipment. Between 2000 and 2008, China’s exports of Machinery and Transportation Equipment to the U.S. surged by 326 percent. The growth rate in this sector has been so rapid that in 2008 its export value alone (156 billion USD) was twice as large as total U.S. exports to China.
It is overwhelming in the case of Japan, in which for many periods their bilateral trade deficit in SITC 7 has exceeded their overall bilateral trade imbalance. In 2008, the deficit in this sector was 86 billion USD, which was well in excess of the overall imbalance (77 billion USD). Although the deficit in this sector with Japan has not expanded as fast as that with China, for the last few years, the amount of the deficits with the two countries has been quite comparable.
According to Xing and Wan (2006), China has become the largest receiver of Japanese FDI in Asia. Table 1 below summarizes the cumulative rise of Japanese FDI in China by major manufacturing sectors. The data do not include the reinvestment by existing Japanese affiliated firms. Machinery and Transport Equipment including subcategories such as General Machinery, Electric Machinery, Transportation Equipment and Precision Machinery takes the lead in receiving Japanese FDI followed by Manufactured Goods. In 1992, Japanese firms invested 109 billion Yen in Machinery and Transport Equipment and the amount rose quite rapidly to 2,625
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billion Yen in 2008, about 30 folds for a decade and a half. Xing (2007) indicates that among them the investment expansions in Transportation Equipment are Toyota, Honda and Nissan. According to the Quarterly Survey of Overseas Japanese Subsidiaries, in 2002 total exports by all sectors of Japanese firms in China to the third countries was 8.3 billion USD and they grew about 220 percent to 26.5 billion USD in 2008. Among all sectors, exports in Machinery and Transport Equipment were the largest. Electrical Machinery ranked number one accounting for 77 percent and 60 percent of total exports to non-Japanese markets in 2002 and 2008, respectively. That was followed by General Machinery and Transport Equipment.. Table 1: Cumulative Japanese Direct Investment in China
SITC 0&1 2 3 5 6 7 ITEM LIST Food and Live Animals Crude Materials, Inedible, except Fuels Mineral Fuels, Lubricants and Related Materials Chemicals and Related Products, N.E.S. Manufactured Goods Classified Chiefly by Material Machinery and Transport Equipment Amount in Billion Yen 1992 16 35 13 12 109 2000 100 225 106 130 762 2008 242 407 44 409 489 2,625
Source: Ministry of Finance, Japan
III. Model Specification and Data
Standard trade equations using the “elasticities” approach has a very long history and has been accepted as part of most policy and empirical study in the field of international economics. Adler (1945), Adler (1946), Chang (1945-46) and Houthakker and Magee (1969) relate demand for exports and imports to a country’s income and its relative prices under the assumption of two countries producing products of imperfect substitutes and homogeneity in prices and incomes. To date, the use of real exchange rates instead of relative prices has become more popular especially when the devaluation of bilateral exchange rates has become the blame to cause huge U.S. trade
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deficits. Hooper and Marguez (1993) summarize the conceptual relationship between relative prices, real exchange rates, and the terms of trade and suggest that the deviations among those variables vary depending on the shares of nontradables in national outputs. Regardless of the regression methods, these simple export and import demand equations are still used in most of the empirical work to date (see also Bahmani-Oskooee & Ardalani, 2006; Chinn, 2004; Hooper, Johnson & Marguez, 2000). The specifications can be written as follows:
log IM ijkt = α 0 + α 1 log GDPikt + α 2 log REX ijt + vijkt log EX ijkt = δ 0 + δ 1 log GDPjkt + δ 2 log REX ijt + eijkt
(1) (2)
where IM, EX, GDP and REX represent real imports, exports, gross domestic products, and real exchange rate, respectively. Subscripts stand for country i, trading partner j, sector k and time t.
α 1 and δ 1 are income elasticities; and α 2 and δ 2 are price elasticities. With an implicit assumption
that there is no income elasticity gap between export and import equations (i.e. the income elasticities of both imports and exports are symmetric (α 1 = δ 1 ) )1, subtracting exports from imports yields: log IM ijkt EX ijkt = (α 0 ? δ 0 ) + α 1 log(GDPikt GDPjkt ) + (α 2 ? δ 2 ) log REX ijt + (vijkt + eijkt )
(
)
(3)
To test our hypotheses, equation (3) is augmented with the variable of interest, the Japanese FDI to China and a deterministic time trend dummy to capture the momentum of the deficits. The model is estimated for each U.S. trading partners, China and Japan, separately. For simplicity, the
1
This could be a strong assumption given the evidence found by Houthakker and Magee (1969) and Chinn (2004).
However, at the commodity level as well as on the bilateral basis, Bahmani-Oskooee and Ardalani (2006) and Bahmani-Oskooee and Wang (2007) find mixed results.
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notations are abbreviated and the model is specified as follows:
TDujkt = λ0 + λ1 RGDPujkt + λ 2 REX ujt + λ3 JDI jckt + λ 4TREND + υ ujkt TDuckt = β 0 + β 1 RGDPuckt + β 2 REX uct + β 3 JDI jckt + β 4TREND + u uckt
(4) (5)
where now the subscripts, u, c and j, stand for the U.S., China and Japan, respectively. The dependent variable (TD) is the U.S. bilateral trade deficit. The explanatory variables consist of the relative GDP of the U.S. to that of its partner (RGDP), the bilateral exchange rate (REX) and Japanese FDI to China (JDI). All these variables are in real terms and natural logarithmic forms.
It is postulated that the increase in income of an importing economy relative to that of its trading partner would raise the imports relatively more than its exports, hence deteriorating the trade deficit. Therefore, the coefficients (λ1 and β1) are expected to be positive. The coefficients (λ2 and β2) are also expected to be significantly positive because if Marshall-Lerner condition holds, the appreciation of U.S. dollar makes its U.S. goods relatively more expensive; in other words, the depreciation of the trading partner’s currency makes U.S. imports relatively cheaper, worsening U.S. bilateral trade deficit.
JDI is the variable of interest. It is the real stocks of Japanese FDI in China because of the fact that the stock rather than flow variable that is deemed to be the engine for export growth. While Japanese FDI to China is hypothesized to reduce the trade imbalance between the U.S. and Japan, it is expected to raise U.S. trade deficit with China. Hence, the coefficient (λ3) is expected to carry a negative sign while β3 would be significantly positive.
The estimation is based on panel data covering six sectors from 1981 to 2007. The model is
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estimated using the fixed-effects (FE) and random-effects (RE) regression methods with White cross-section standard errors to correct for heteroskedasticity in the error term. Using panel data constitute an advantage of controlling for unobserved cross-section specifics. The descriptive statistics of all variables are presented in Table 2.
Table 2: Descriptive Statistics
Obs Variables TD RGDP REER REX JDI Description U.S.-Japan Equation Log of relative imports to exports Log of relative U.S. GDP to Japanese GDP Log of Real effective exchange rates Log of Real exchange rate Log of Real Japanese direct investment 162 162 162 162 125 -0.903 0.491 4.383 4.803 19.688 1.997 0.393 0.171 0.191 2.222 -5.028 -0.521 4.055 4.437 14.377 2.382 1.365 4.708 5.153 23.728 Mean Std. Dev Min Max
U.S.-China Equation TD RGDP REER REX JDI Log of relative imports to exports Log of relative U.S. GDP to Chinese GDP Log of Real effective exchange rates Log of Real exchange rate Log of Real Japanese direct investment 162 162 162 162 125 0.497 2.435 4.766 1.973 19.688 1.811 0.501 0.342 0.226 2.222 -2.987 1.503 4.331 1.338 14.377 6.851 3.308 5.547 2.248 23.728
U.S bilateral trade flows by sectors with Japan and China are the combined data from the UN Comtrade database and the U.S. International Trade Commission. Both imports and exports are deflated with the U.S. consumer price index (CPI 2000), extracted from World Bank’s World Development Indicator (WDI). The Japanese GDP by sector is obtained from the Cabinet Office and the U.S. GDP by sector is obtained from the Bureau of Economic Analysis. Both variables are deflated by the CPI of respective countries. Real GDP of the U.S. and that of China are downloaded from WDI2. The unit labor cost (ULC) deflated real effective exchange rate is
2
Because the sectoral GDP data for China are not available, the aggregate data are used instead which means that
the relative GDPs over time are the same for all sectors.
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obtained from International Financial Statistics (IFS) as well as the real exchange rates are calculated based on IFS. The Japanese direct investment in China is downloaded from the Ministry of Finance, Japan and deflated by the Japanese CPI with 2000 as the base year.
IV. Empirical Evidence
Equation (4) is estimated and the results from fixed and random-effects are presented in Table 3. Since the hot policy debates on the currency devaluation being the cause of U.S. trade deficits have been overwhelm, we alternatively include two measures of exchange rate, unit labor cost (ULC) deflated real effective exchange rate and consumer price index (CPI) deflated real exchange rate. Due to missing observations of the Japanese FDI in China, especially those of
MINERAL FUELS, LUBRICANTS AND RELATED MATERIALS (SITC 3), the panel is not
completely balanced; therefore, only 125 observations are included.
Regardless of the estimation methods, the results show that the estimates of the relative GDP have the expected significant sign at a one percent level, indicating that the increase in the relative GDP of the U.S. to that of Japan intensifies the trade imbalance between the two countries, ceteris paribus. That also suggests that the higher income of the U.S. results in higher demand for goods imported from Japan. According to the estimated coefficients obtained in Table 3, the difference in U.S. GDP growth from Japan contributes to a roughly one to one rise in its bilateral trade deficit.
On the other hand, the results provide a mixed, contrasting evidence for the exchange rate. When ULC deflated real effective exchange rate is used, we find a positive relationship between real exchange rate devaluation and the deteriorating trade imbalance. Nonetheless, when the real
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exchange rate is used, the coefficient turns out to be negative. They are both significant at a one percent level. Though, the sign is not consistent with the prediction, using bilateral real exchange rate may sufficiently justify our bilateral model.
Table 3: U.S. bilateral trade deficit with Japan and Japanese FDI in China Dependent Variable: Explanatory Variables Constant RGDP REER REX JDI TREND Adj. R2 No. of Observations U.S. bilateral trade deficit with Japan Fixed Effects ___ 1.080 (6.462)*** 0.864 (3.224)*** ___ -0.140 (-1.842)* 0.059 (2.634)*** 0.971 125 ___ 1.453 (7.801)*** ___ -1.300 (-4.373)*** -0.158 (-2.125)** 0.069 (3.074)*** 0.973 125 Random Effects -3.105 (-2.150)** 1.079 (6.468)*** 0.861 (3.322)*** ___ -0.140 (-1.947)* 0.059 (2.789)*** 0.350 125 6.879 (3.393)*** 1.450 (7.327)*** ___ -1.296 (-4.474)*** -0.157 (-2.280)** 0.068 (3.315)*** 0.388 125
Note: Figures in parenthesis are t-statistics. *** denotes significance at 1%, ** at 5%, * at 10%. Heteroskedasticity is corrected (White cross-section standard errors & covariance).
Our interesting findings are pretty much as we have expected. Regardless of the estimation methods and which exchange rate variables included, the estimate of the Japanese FDI carries a negative sign, thus suggesting that the bilateral trade imbalance between the two countries is negatively affected by the Japanese FDI in China. The coefficients are at least marginally significant at a 10 percent level. The results indicate that a one percent increase in Japanese direct investment in China reduces the U.S. trade deficit with Japan by approximately 0.15 percent. Because both estimation methods produce very similar results, the Hausman test, used to
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check the relative efficiency of each estimation method, is deemed to be unnecessary.
Table 4 shows the results of equation (5) which evaluates the impact of Japanese FDI on U.S. trade deficit with China. Similarly, the coefficient of relative real GDP is positive and significant at a one percent level. The increase in the relative GDP of the U.S. to that of China raises the trade deficit between the two countries. It is worth noting that the magnitude is twice as great as that of relative income in the U.S.-Japan equation, indicating that higher demand for Chinese imports due to higher income could deteriorate the bilateral deficit more than U.S.-Japan deficit.
Table 4: U.S. bilateral trade deficit with China and Japanese FDI in China Dependent Variable: U.S. bilateral trade deficit with China Explanatory Variables Constant RGDP REER REX JDI TREND Adj. R2 No. of Observations Fixed Effects ___ 2.601 (3.218)*** 0.095 (0.349) ___ 0.366 (5.022)*** 0.128 (2.279)** 0.780 125 ___ 2.591 (3.020)*** ___ 0.185 (0.496) 0.344 (5.298)*** 0.127 (2.153)** 0.780 125 Random Effects -12.043 (-3.748)*** 2.386 (2.995)*** -0.092 (-0.356) ___ 0.274 (4.198)*** 0.136 (2.431)** 0.353 125 -12.883 (-4.671)*** 2.335 (2.850)*** ___ 0.289 (0.807) 0.275 (4.515)*** 0.130 (2.274)** 0.354 125
Note: Figures in parenthesis are t-statistics. *** denotes significance at 1%, ** at 5%, * at 10%. Heteroskedasticity is corrected (White cross-section standard errors & covariance).
The findings do not appear to be in line with Xu (2008) who calls for the revaluation of Yuan to ease the imbalances between the two nations. The results indicate that the coefficients of exchange rate, no matter which measure of exchange rate is used, in both methods are small and
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are not statistically significant. That is, the depreciation of Chinese Yuan does not seem to be one of the factors affecting the enormous amount of U.S.-China trade imbalance. However, the findings support other studies (Goldberg & Dillon, 2007) in which it is unlikely that the depreciation of dollar alone will close the trade gap because the price of foreign imports for U.S. consumers will be considerably more resilient to exchange rate movement.
Importantly regardless of estimation methods, the findings in Table 4 provide evidence to support our argument that Japanese FDI in China plays significant role in mounting U.S. bilateral trade deficit with China. The coefficients of Japanese FDI, no matter which exchange rate variable is employed, are positive as expected and significant at a one percent level though they are larger in the fixed effects method. Overall, a one percent rise in FDI of Japanese firms in China increases the ratio between U.S. imports from and exports to China by roughly 0.30 percent. Compared with the estimates of the effect of Japanese FDI on U.S.-Japan trade deficit, the effect on U.S.-China trade is twice as large as that on U.S.-Japan trade, indicating that investment of Japanese firms in China is partly substituting for its exports to the U.S. market so as to meet higher demand growth.
V. Conclusion
The paper postulates that Japanese direct investment in China has played an important role in the U.S.’s bilateral trade imbalances with Japan and China. More specifically, the relocation of Japanese firms to China has reduced the share of U.S. trade deficit with Japan while widening the gap of its trade imbalance with China. Using cross-sectoral data from 1981 to 2007, we estimate the trade imbalance models for each U.S. trading partner, China and Japan. The results support our argument, suggesting the tradeoff between the deficits of U.S. trade with Japan and
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that with China. Particularly, a one percent increase of Japanese FDI in China lowers the ratio of imports to exports between the U.S. and Japan by about 0.15 percent while raising that with China by approximately 0.30 percent, twice as much as the corresponding reduction.
We find evidence that the relative growth of U.S. income to its trading partner has significant impact on its mounting trade imbalance. Moreover, while the empirical results provide inconclusive evidence to support to the effect of real exchange rate on U.S-Japan trade imbalance, the effect of bilateral exchange rate between the U.S. and China is found to be insignificantly small, hence no relationship with deteriorating U.S.-China trade deficit. The findings reject the hypothesis that the revaluation of Chinese Yuan would turn around the U.S. bilateral trade deficit with China.
The findings have important policy implications for U.S. trade deficits in general and with China in particular. The fact that the accumulation of Japanese FDI in China has been associated with the rapid growth of U.S. trade deficit with China highlights the potential role of Japanese firms in easing U.S. trade imbalance if there are in place policies conducive to Japanese FDI in the U.S. It is worth noting that the U.S. received a sizable share of Japanese FDI outflows in the 1950s. However, China has gained momentum in attracting FDI from Japan and other countries, including the U.S. itself thanks to its large labor endowment coupled with national policies encouraging FDI inflows to boost exports. It is evident that protectionist trade policies may not work to decrease trade deficits in the long-run but policies to attract and retain U.S. firms and firms from other countries to build production facility in the U.S. will help change macroeconomic fundamentals, thereby reducing trade deficits.
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References Adler, J. H. (1945). United States Import Demand During the Interwar Period. The American Economic Review, 35, 418–30. Adler, J. H. (1946). The Postwar Demand for United States Exports. Review of Economic Statistics, 28, 23–33. Bahmani-Oskooee, M. & Ardalani, Z. (2006). Exchange Rate Sensitivity of U.S. Trade Flows: Evidence from Industry Data. Southern Economic Journal,72, 542-559. Bahmani-Oskooee, M. & Wang, Y. (2007). United States-China Trade at the Commodity Level and The Yuon-Dollar Exchange Rate. Contemporary Economic Policy, 25, 341-361. Burke, J. (2000). U.S. investment in China worsens trade deficit: U.S. firms build export-oriented production base in China’s low-wage, low labor-protection economy. Economic Policy Institute, Briefing paper. Bureau of Economic Analysis, U.S. Department of Commerce. Washington, DC: Author. Retrieved February 25, 2009, from https://www.sodocs.net/doc/0c4701432.html,/bea/ai1.htm#USDIA Cabinet Office, Japan. Statistics. http://www.cao.go.jp/ Chang, T. C. (1945–46). International Comparison of Demand for Imports. The Review of Economic Studies, 13, 53–67. Chinn, D. M. (2004). Incomes, Exchange Rates and the U.S. Trade Deficit, Once Again. International Finance, 7, 451-69. Goldberg, L. and Dillon W. E. (2007) Why a Depreciation May Not Close the U.S. Trade Deficit. Current Issues in Economics and Finance. Federal Reserve Bank of New York. Houthakker, S. H. & Magee, P. S. (1969). Income and Price Elasticities in World Trade. The Review of Economics and Statistics, 51, 111-25. Hooper, P., Johnson, K. & Marguez, J. (2000). Trade Elasticities for the G-7 Countries. Princeton Studies in International Economics. Hooper, P. & Marguez, J. (1993). Exchange Rates, Prices, and External Adjustment in the United States and Japan. International Finance Discussion Papers, No. 456. International Monetary Fund. International Financial Statistics CD 2009 Klitgaard, T., & Schiele, K. (1997). The growing U.S. trade imbalance with China. Current Issues in Economics and Finance. Federal Reserve Bank of New York.
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Kojima, K. (1978). Direct foreign investment: A Japanese model of multinational business operations. London: Croom Helm. Ministry of Finance Japan (2004). Foreign direct investment. Tokyo, Japan: Author. Retrieved February 25, 2009, from http://www.mof.go.jp/english/fdi/reference03.xls Xing, Y. (2006). Japanese FDI in China: Trend, structure, and the role of exchange rates. In K. H. Zhang (Eds.), China as a world factory. Routledge, Taylor & Francis. Xing, Y. (2007). Foreign Direct Investment and China’s Bilateral Intra-Industry Trade with Japan and the U.S. BOFIT Discussion Papers 1/2007. Xing, Y and Wan, G. (2006). Exchange Rates and Competition for FDI in Asia. The World Economy, 29: 419-34. Xu, Z. (2008). China's exchange rate policy and its trade balance with the U.S. Review of Development Economics,12, 714-727 United Nations Conference on Trade and Development. UN Comtrade Database. Geneva, Switzerland. https://www.sodocs.net/doc/0c4701432.html,/ United States Census Bureau. Trade in goods (imports, exports and trade balance) with China. Washington, DC: Author. February 25, 2009, from.
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United States International Trade Commission. ITC Trade DataWeb. https://www.sodocs.net/doc/0c4701432.html,/ World Bank. World Development Indicator CD 2008.
Page 19

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净水器使用说明书

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书 宜兴市环球水处理设备有限公司

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轻松进入sciencedirect的方法(有问题联系:wmwman306@https://www.sodocs.net/doc/0c4701432.html,) 这种方法很好进入sciencedirect,也无须验证代理的有效性。步骤如下: 1.代理 查找及设置 https://www.sodocs.net/doc/0c4701432.html,/codeen/ (1)页面如图: (2)点击“status”,代理自动按照状态排序,选择“summary failed”的代理,如下图的第一个代理“139.19.142.3”,复制它.

(3)点击网页的“工具”--“internet 选项”--“连接”--“局域网设置”,选上“代理服务器”复选框,在“地址栏”输入刚才的代理“139.19.142.3”,在“端口”输入“3124”或“3127”或者“3128”,如下图我就输入“3128”。点击“确定”--“确定”,代理就这样设置完成了.

2.进入sciencedirect开始了,很关键,关键是网址变了 (1)在网页地址栏里的输入有三种选择好(呵呵,我只知道三种): https://www.sodocs.net/doc/0c4701432.html,/ 或者 https://www.sodocs.net/doc/0c4701432.html,/ 或者 https://www.sodocs.net/doc/0c4701432.html,/ (2)注意:初次进入可能进的不是sciencedirect主页,而是codeen介绍主页,这是你再输入刚才的网址刷新一下就好了 (3)进入主页如下图,有“Advanced Search ”字样的说明现在你能查阅它里边的文献了。点击“Advanced Search ”,就可以按照你的要求查阅相关文献了。

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Installation Instructions AQ-5200 & AQ-5300 Under Counter Water Filter Two Stage (5200), Three Stage (5300) systems Welcome to the Aquasana experience. You are about to enjoy clean, healthy water and the peace of mind that comes from knowing award-winning filter technology is working for you. Installation must comply with state and local laws.

Aquasana, Inc. 6310 Midway Road Haltom City, Texas 76117 866.662.6885 USA 877.332.7873 Canada https://www.sodocs.net/doc/0c4701432.html, For exclusive deals https://www.sodocs.net/doc/0c4701432.html,/aquasana https://www.sodocs.net/doc/0c4701432.html,/aquasana System tested and certified by NSF International against NSF/ANSI Standard 42 and 53 for the reduction of the claims specified on the Performance Data Sheet and at https://www.sodocs.net/doc/0c4701432.html,.

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3.请勿随意更改电路和管路。 4.请勿自行调节高、低压开关等控制组件,如因自行调节造成损失,本公司概不负责。 5.出现故障请与当地经销商联系,请勿随意更改。 机器性能及安装条件

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RO-5000型反渗透纯水机采用先进的单级低压反渗透技术对自来水进行提纯。结合精心设计的过滤和吸附系统,能有效的去除水中各类细菌、残留物、重金属离子等并有害健康的物质、更能去除常规手段无法去除的三氯甲烷、氟等致癌致病物。国内绝大部分地区自来水电导率都≤500us/cm,因此采用本机制水,一定要注意原水品质,并且严格按照说明书操作、维护和保养,所制纯净水电导率完全能保持在国家标准规定的10us/cm以下,确保制取直接生饮的纯净水,符合卫监发(1998)第19号文件附件4卫生要求及卫生部GB5749-85《生活饮用水卫生标准》。 RO-5000型反渗透纯水机,将完善正规的饮用纯净水制作工艺集为一体,柜架式敞开设计、流程清晰、易于维护保养。可作为社区、工业区、油田等净水屋的核心设备,也可作为食品、饮料、化工、医院、电子等行业的水处理设备。 进水水质:需符合GB5749-85《生活饮用水卫生标准》,且电导率≤500us/cm的自来水。 出水水质:符合“卫生部卫监发(1998)第19号文件卫生”要求。 二、主要参数 每个设备的工作周期如下: 1、石英砂过滤器 累计工作3天,进行15分钟反冲洗。 累计工作2900小时,应更换石英砂滤料。 2、活性炭吸附滤器: 当出口余氯含量>0.1mg/L时,应更换活性炭滤料,一般情况下累计工作一年后,应该更换活性炭滤料。 3、树脂软化器:

当在正常对树脂进行交换后,纯净水的硬度超出标准时要及时更换树脂。一般情况一年左右换料。 4、保安过滤器: 一般情况下,累计工作1个月后应更换精滤芯。当精滤器在工作时出水压力<0.04Mpa时也应更换精滤芯 5、预处理操作: 此设备为阀头控制,在第一次使用前应对其预处理进行彻底冲洗,用手操作阀头上的手柄,至每一个冲洗位置,将冲洗出来的水变清为止。 软化头冲洗同上所述,对树脂再生可手动操作。 反渗透过滤器 累计工作240小时,应用药物清洗RO膜一次。 累计工作2900小时后应更换RO膜。 特别注意:为了您的安全、请务必将机器接地线可靠接地。 三、设备安装调试操作步骤: 1、将主机放置在接近水源和电源的地方。 2、连接水路:原水泵进水口与水源连接、预滤器出口与主机进口连接,主机排水口均用管路连接 至下水道。 4、电路:首先将接地线可靠接地,并将随机所配电源线接到房间电控箱内。 5.开机前先检查设备状况,并确认安全,方能开机制水. 整机安装注意事项: 1、设备安装场地应平整、环境整洁、紧靠电源、水源。 2、请勿靠近火源及任何发热体。 3、在北方地区不得将设备安装在室外,以防设备内部冻结,损坏仪表及过滤元件。 4、设备安装位置应能方便排水,使设备的排水管保持顺畅。 1)当进水压力<0.10Mpa。流量<5.0T/H时,本机运行中会反复出现增压泵起动---停止---起动的现象。这时本机就要停止使用,防止烧毁电机,水压和流量不足的地区,请在本设备前增加原水罐。

数据资源管理平台

1 数据资源管理平台设计 1.1 需求分析 1.1.1 数据需求 1.1.1.1 数据分析 XX省水资源管理系统业务涉及的信息资源包括信息采集和信息共享。信息采集按获取方式应分为仪器自动在线监测和非在线监测两种采集范畴。以共享方式获取的其他信息获取(包括水文、水资源保护部门负责采集的实时水雨情、水质监测数据),属于信息共享范畴。 信息采集传输应充分利用现代化科技成果,通过对信息采集和传输基础设施设备的改造和建设,配置适合当地水资源特性的仪器设备。信息采集传输的设备选型与配置应充分考虑当地的水文、气候特征、供电条件和环境安全等因素。 (1)在线监测信息对象 在线监测信息对象包括:水源地、取用水、行政边界河流控制断面、地下水超采区以及水功能区水量水质信息。监测规模、监测手段和监测代价的衡量要应充分考虑当地的经济发展水平、经济承受能力、设站技术可行性和运行维护便捷性。 水源地监测:包括地表水水源地(水库、江河、湖泊等水体)和地下水水源地。应按照先列入水利部公布的全国重要饮用水水源地名录的水源地、大中型水库水源地,后其它饮用水水源地的顺序安

排布设。 取用水监测:包括重点取水口水量水质监测。按照先取水环节后排水环节、先集中用水户后分散用水户顺序安排;取水量级考虑先重点用水户后一般用水户、同等取水量级先第二、三产业用水户后第一产业用水户顺序安排;同时兼顾设站条件通盘考虑。 水资源管理单元出入断面监测:包括省际、地市际以及县际边界河流控制断面。按照先地市际边界河流控制断面监测后县际边界河流控制断面的监测,水资源管理单元逐级细化、控制能力逐步加强的思路顺序建设。 水功能区监测:按照《XX省水功能区规划》的部署,按照先保护、保留、缓冲、饮用水源等重要水功能区水质监测、后其余水功能区水质监测、入河排污口监测的原则布设。 地下水超采区监测:包括地下水水位、水质监测。按照先禁采区限采区、后地下水集中开采区、先平原区后山丘区的顺序安排布设。 水生态监测:重点区域和水域水生态监测。按照先水利部水生态系统保护与修复试点后其它区域的顺序安排布设。 社会用水户、水源地、水资源管理单元出入断面、水功能区、地下水水量水质监测点的布设应在充分利用既有水文观测站网络的基础上统筹规划,有些观测面监测可通过上下游监测点观测数据内插方式满足,有些可通过既有测站增加观测项的方式满足。 (2)新设监测点的工作方式

净水器中文说明书

反渗透水质处理器主要功能 家用反渗透水质处理器,协调完成纯水制造的自动化过程。在安装好的情况下,打开水源,低压开关自动闭合,反渗透水质处理器开始制水。当储水桶的水满时,高压开关断开。饮用纯净水同时,储水桶内的压力会逐渐下降,反渗透水质处理器又开始制水。当水源断水时,低压开关自动断开,反渗透水质处理器处于停机状态;反之,低压开关闭合开始制水。让您随时都可以喝到甘甜可口的纯净水。 新安装的反渗透水质处理器,应防掉一至二桶的纯水冲洗新机后,方可开始饮用。 特别注意 1.本机必须由专业人员安装,在使用前详细阅读说明书,以免对您正常饮水造成不必要的 麻烦。 2.用户若数天不用(外出),应关闭本机电源及水源。 3.以包装箱内实际配置为准 4.安装完毕请检查螺帽是否紧固以免漏水,无地漏或者地漏不完善之场所严禁安装本公司 产品,否则造成财产损失,本公司概不负责。 安装及使用注意事项 为了防止危害使用者安全,损害他人财物事件的发生,请务必严守一下说明 1.安装服务人员在安装前应先检查系统电路部分是否正常,因为在运输装卸过程中有可能 引起接线松动,组件损坏。 2.如果您要自选安装,请严守安装说明。 3.请勿随意更改电路和管路。 4.请勿自行调节高、低压开关等控制组件,如因自行调节造成损失,本公司概不负责。 5.出现故障请与当地经销商联系,请勿随意更改。 机器性能及安装条件 序号项目参数 1工作电压AC220V~DC24* 2最大日制水量50加仑(约190公斤) 3压力储水桶容量3.0加仑(余额12公斤) 4水温要求5~45℃ 5T.D.S最大限值450ppm以下 6去除率96%以上** 7配置方法五级带泵 8冲洗方法自动 9进水压力0.1~0.35Mpa*** 10低压设定值0.05~0.08Mpa 11高压设定值0.25~0.35Mpa 12自动冲洗时间设定值18秒~8秒 *不可在高于220V的电压下长时间运作 **去除率=[(原水T.D.S值-纯水T.D.S值)*100%]/原水T.D.S值 ***低于0.1Mpa需加装增压泵,高于0.35Mpa需加装减压泵。

饮水机使用方法

饮水机的正确使用和消毒维护 (2010.2.2) 一、饮水机的正确使用 1.饮水机应平放在坚固平整的地面(立式)或台面(台式),注意垫平; 双温机的背面应与墙壁保持8-10厘米的间距, 以利散热。 2.室内应使用接地良好的三线插座, 并安装漏电保护开关, 确保 饮水机有良好的接地、安全使用。 3.使用大瓶装带聪明盖水瓶时,先撕下瓶盖上之标贴,将水瓶倒置于饮水机聪明座上,聪明柱会自动顶开聪明盖,让水注入饮水机水罐。打开热水龙头,直至有水流出,方可插上电源! 4.打开加热、制冷开关,红、绿两个指示灯同时亮,机器开始工作(制热、制冷)。加热红灯自动熄灭(单色灯)或变为黄灯时,表明热水温度已达90度左右;制冷绿灯自动熄灭(单色灯)或变为黄灯时,冷水温度巳达15度左右。 ※使用饮水机之前应仔细阅读使用说明书,确保根据不同机型进行 正确操作! 二.饮水机的维护保养 1.在维修、维护之前必须拔下电源插头! 2.不要用有害健康的清洁剂或化学物质清洗饮水机水罐等部件。 3.不要直接对饮水机外壳淋水,应用浸水软织物擦净机身。 4.如果冷凝器上有灰尘或异物堆积,应用浸水软织物擦拭。 5.擦拭完毕,使其完全干燥后,先加满水,待热水龙头出水后方可

再插上电源! 6.饮水机使用矿泉水或过滤水(非纯净水)易使电热管表面结垢,结垢会影响制热的效率并使加热噪声增大(严重时会烧坏电热管)。可用饮水机专用除垢剂对热罐、电热管除垢;每隔30天左右应对饮水机进行一次消毒、清洗。※饮水机除垢和消毒、清洗, 可由维修服务人员进行有偿服务。 7.若熔断器熔断,可打开接线盒盖,用5A(压缩机制冷用10A)新保险管更换。 8.饮水机出现干烧等情况时,制热系统的过热保护(97℃)温控器将会动作(跳断),这时需手动复位。若电源线损坏,必须用与本机相同的特殊电源线来更换。 三、饮水机使用与保养常识 (1)搬运机器要轻拿轻放,搬动压缩机制冷的饮水机时,应尽量保持直立移动,若要倾斜时,其倾不得大于45度,且搬运后要静止一段时间后,方可工作。 (2)初次使用饮水机时,应用清水对饮水机各容器及管路进行清洗,然后旋开排水阀,待排完机内余水后拧紧排水阀。加上大瓶水后,打开热水龙头,有水流出后方可插上电源、打开加热开关,避免干烧,延长机器寿命。 (3)饮水机长时间停用,请关闭机器开关并将电源插头拔下,然后旋开排水阀,排完机内余水,再拧紧排水阀(排水过程中请注意热水烫伤)。

数据库管理系统的设计与实现

数据库管理系统的设计与实现 1.DBMS的目标 (1)用户界面友好对一个实用DBMS来说,用户界面的质量直接影响其生命力。DBMS的用户接口应面向应用,采用适合最终用户的交互式、表格式、菜单式、窗口式等界面形式,以方便使用和保持灵活性。一般地说,用户界面应具有可靠性、简单性、灵活性和立即反馈等特性。 (2)功能完备DBMS功能随系统的规模的大小而异。大型DBMS功能齐全,小型DBMS功能弱一些。DBMS主要功能包括数据定义、数据库数据存取、事务控制、数据库组织和存储管理、数据库安全保护等等。我们在下面讨论这些功能的内容。 (3)效率高系统效率包括三个方面:一是计算机系统内部资源的使用效率。能充分利用资源(包括存储空间、设备、CPU等),并注意使各种资源负载均衡以提高整个系统的效率,二是DBMS本身的运行效率。三是用户的生产率。这是指用户学习、使用DBMS和在DBMS基础上开发的应用系统的效率。 2.DBMS的基本功能 (1)数据库定义对数据库的结构进行描述,包括外模式、模式、内模式的定义;数据库完整性的定义;安全保密定义(如用户口令、级别、存取权限);存取路径(如索引)的定义。这些定义存储在数据

字典(亦称为系统目录)中,是DBMS运行的基本依据。为此,提供数据定义语言DDL。 (2)数据存取提供用户对数据的操纵功能,实现对数据库数据的检索、插入、修改和删除。一个好的DBMS应该提供功能强易学易用的数据操纵语言(DML)、方便的操作方式和较高的数据存取效率。DML有两类:一类是宿主型语言,一类是自含型语言。前者的语句不能独立使用而必须嵌入某种主语言,如C语言、COBOL语言中使用。而后者可以独立使用,通常以供终端用户交互使用和批处理方式两种形式使用。 (3)数据库运行管理这是指DBMS运行控制、管理功能。包括多用户环境下的并发控制、安全性检查和存取权限控制、完整性检查和执行、数据加密、运行日志的组织管理、事务的管理和自动恢复(保证事务的正确性),这些功能保证了数据库系统的正常运行。 (4)数据组织、存储和管理DBMS要分门别类地组织、存储各类数据,包括数据字典(亦称系统目录)、用户数据、存取路径等等。要确定以何种文件结构和存取方式在存储级上组织这些数据,如何实现数据之间的联系。数据组织和存储的基本目标是提高存储空间利用率,选择合适的存取方法确保较高存取(如随机查找、顺序查找、增、删、改)效率。 (5)数据库的建立和维护包括数据库的初始建立、数据的转换、数据库的转储和恢复、数据库的重组织和重构造以及有性能监测分析等功能。

FA一体化净水器使用说明书

F A一体化净水器使用说明 书 Prepared on 24 November 2020

FA型一体化净水器安装使用说明书 南京德诺环保工程有限公司 二O一三年十月

一、概述 FA型高效能全自动净水器集絮凝、沉淀、反冲、集水、过滤等工艺于一体;无需专业人员操作而能达到单体全自动运行的净水装置。 本装置包括布水、反应、沉淀、过滤、集水、集泥、自动反洗七个主要单元,内装卵石、各种规格石英砂滤料及无烟煤滤料,设备主壳均为碳钢制作,内外部采用特殊涂料进行防腐处理,使用寿命长,适用范围广,性能卓越,广泛用于大、中、小型水厂(站)的建设和改造。 二、规格及技术参数 1、处理水量:50m3/h 2、进水浊度:≤3000mg/l 3、出水浊度:≤3mg/l 4、沉淀区设计表面负荷:7~8m3/h·m2 5、过滤区设计滤速:8~10m/h 6、滤池冲洗强度:14~161/m2·s 7、冲洗历时:4~6min 8、总停留时间:40~50min 9、进水压力:大约 10、滤料粒径及厚度(双层):900mm 11、运行负荷:80T 三、工艺说明 1、凝聚反应区: 经加药混合后的原水进入一体化净水器,首先进入装置底部的配水区,净水

器的进水为底部配水区进水,穿孔管布水,确保设备布水均匀,并且每个微孔处水流以一定的流速喷出,使絮状污泥与原水中的细小矾花充分接触,前级混合后的原水在污泥的吸附作用下,进行彻底的混凝反应,通过剩余污泥的循环回流,进行絮凝反应,使进水与污泥具有更大的接触面积,提高污泥的凝聚效率,使原水中的小矾花凝聚成较大的矾花,为斜管沉降创造有利条件。 2、斜管沉淀区: 沉降区分为上下两部分,通过改变上下两层的斜管的孔径,提高水力梯度值,依据浅层沉淀理论,设置了斜管加速沉降,下部反应区快速形成的大颗粒状絮体,在两层斜管之间水流方向发生改变,将会增加小颗粒絮体间的接触机会,在流经上层斜管时,进一步提高出水水质。形成的絮状体悬浮物在一层斜管区进行整流,一层斜管起均匀布水及导流作用,经充分反应后絮状水体沿二层斜管倾斜方向往上流动,进入沉降区内进行固液分离,沉积下来的污泥在重力及水流推力的作用下,沿斜管倾斜方向往下滑落。 3、污泥区: 斜管沉淀区沉淀的污泥通过水力的推流及自然沉降,部分经水力推动进入污泥区,部分污泥回流进入高浓度混合反应区,为保证污泥区排泥的彻底性,每套净水器污泥区均设有电动排泥系统及辅助排泥装置。 4、排泥系统: 每套净水器排泥系统由2套电动排泥阀组成,排泥管采用穿孔管结构,沿污泥区底部设置,用于排泥时污泥区的搅动,以利于污泥的彻底排净。系统排泥按设定的时间程序进行,每周期每格污泥区排泥1-3min(排泥时间可调)。 5、集水及滤池配水区:

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