• Title/Summary/Keyword: flow effect

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Efficiency Estimation for Desalination System of Seawater Using Reverse Osmosis Membrane (역삼투압막 해수담수화 장치의 미네럴 분리 성능평가)

  • Moon, Deok-Soo;Jung, Dong-Ho;Kim, Hyeon-Ju;Shin, Phil-Kwon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.2
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    • pp.60-66
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    • 2005
  • When external pressure higher than osmosis pressure is reversely derived into solution, its solvent is moved into the solution having lower concentration, which is called 'reverse osmosis'. We investigated the desalination application of deep ocean water using reverse osmosis pressure of $40-70\;kgf/cm^2$ We observed how to operational factor j like flow rate, water temperature and pressure have effect on efficiency of reverse osmosis membrane and salts rejection. Fluxes of reverse osmosis membrane are directly proportional to water temperature and pressure. However, salts rejection rates are positively correlated with pressure and inversely proportional to water temperature. Separation efficiencies of osmosis membrane for major elements such as $Mg^{2+},\;Ca^{+2},\;Na^+\;and\;K^+$ are as follows in a strong electrolysis solution like seawater; $Ca^{2+},\;Mg^{2+}>K^+>Na^+$. Rejection rates of $Mg^{2+}\;and\;Ca^{2+}$ that have high electric charges are over 99% and show positively correlation with water temperature. Rejection rates of $Na^+$ having low electric charge is observed to be 98%-99%, which rates is much lower than those of $2^+$ charged ions like $Ca^{2+}\;and\;Mg^{2+}$. Ion rejection rates of boron, B, are much low because boron is present il free state or gas phase in seawater. Boron concentration in desalination water is over criteria of Korean drinking water, 0.3 mg/L. However, we could satisfied with the criteria of drinking water under the operation condition like temperature $5^{\circ}C$ and pressure $70kgf/cm^2$, using the relationship that rejection rates of boron is proportional to pressure and is inversely proportional to water temperature

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The effect of postural abdominal breathing exercise on posture muscle activity and respiratory function in adults in their 20s (자세에 따른 복식호흡 운동이 20대 성인의 자세근육 활성도 및 호흡 기능에 미치는 영향)

  • Lee, Jun-cheol
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.2
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    • pp.341-348
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    • 2020
  • This research is to find out which position is more effective on exercise. This study compared paricipants in their twenties on sitting position & standing position doing abdominal breathing of their respiration & abdominal muscle activation for 4 weeks. In sitting position, FEV1 was the biggest after breathing exercise. In standing position, the gap was biggest between the FEV1 & forced expiratory flow before and after the exercise. In standing and supine position, Lt. rectus abdominis before exercise and Rt. rectus abdominis after exercise muscle activities were the biggiest. Both posture exercise of repeated measure of analysis result, before and after the exercise of the rectus abdomonis muscle and external oblique muscle were not difference in both muscle activity(p>.05). Left Musculus obliquus externus abdominis before and after physical exercise, it's showed a meaningful difference(p<0.05). Before and after exercise, saw a meaningful difference the efforts of FEV1/FVC(p<0.05). The left external oblique abdominis muscle showed the most muscle activity in the supine position before/after exercising, the efforts expiratory showed the lowest muscle activity.The results from the repeated measures ANOVA regarding to before/after the volume and muscle activity, it showed significant difference between at the right rectus abdominis muscle(p<.05). This study finally gathered data about the muscle activity according to the position. This could be used to find in what position the abdominal breath exercise is the post effective & a new treatment for the patients who has worsened respiration function.

Dysfunction of Autonomic Nervous System in Patients with Chronic Obstructive Pulmonary Diseases (만성 폐쇄성 폐질환 환자의 자율신경 장애)

  • Shin, Kyeong-Cheol;Lee, Kwan-Ho;Park, Hye-Jung;Shin, Chang-Jin;Lee, Choong-Ki;Chung, Jin-Hong;Lee, Hyun-Woo
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.3
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    • pp.317-326
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    • 1999
  • Background: Neural control of airway function is through parasympathetic, sympathetic and non-adrenergic, non-cholinergic mechanisms. The autonomic nervous system controls the airway smooth muscle tone, mucociliary system, permeability and blood flow in the bronchial circulation and release of mediators from the mast cells and other inflammatory cells. The cardiovascular and respiratory autonomic efferent fibers have a common central origin, so altered cardiovascular autonomic reflexes could reflect the altered respiratory autonomic status. Therefore, we performed this study to assess the autonomic abnormality and determine the correlating factors of severity of autonomic neuropathy in patients with chronic obstructive pulmonary disease(COPD) using easily reproducible cardiovascular autonomic reflex function test. Method: The study included 20 patients with COPD and 20 healthy persons obtained on Health Promotion Center in Yeungnam university hospital. All the patients had history and clinical features of COPD as defined by the American Thoracic Society. Any patients with myocardial ischemia, cardiac arrythmia, hypertension, central or peripheral nervous system disease, diabetes mellitus, or any other diseases known to produce autonomic neuropathy, has excluded. The autonomic nervous system function tests included three tests evaluating the parasympathetic system and two tests evaluating the sympathetic system. And also all subjects were subjected to pulmonary function test and arterial blood gas analysis. Results: Autonomic dysfunction was more commonly associated with patients with COPD than healthy person The parasympathetic dysfunction was frequent in patient with COPD, but sympathetic dysfunction seemed preserved. The severity of parasympathetic dysfunction in patients with COPD was correlated with the degree of duration of disease, smoking, reductions in the value of $FEV_1$ and FVC, and arterial hypoxemia but no such correlation existed for age, type of COPD, $FEV_1$/FVC, or $PaCO_s$. Conclusion: There is high frequency of parasympathetic dysfunction associated with COPD and the parasympathetic abnormality in COPD is increased in proportion to severity of airway disease. In COPD, parasympathetic dysfunction probably does not the cause of disease, but it may be an effect of disease progression.

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Effect of Hypothermia on the Prevention of Ventilator-Induced Lung Injury in Rats (백서에서 저체온 전처치가 환기기유발폐손상 억제에 미치는 효과)

  • Lim, Chae-Man;Hong, Sang-Bum;Koh, Youn-Suck;Shim, Tae-Sun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.5
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    • pp.540-548
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    • 2001
  • Backgrounds : Because ventilator-induced lung injury is partly dependent on the intensity of vascular flow, we hypothesized that hypothermia may attenuate the degree of such an injury through a reduced cardiac output. Methods : Twenty-seven male Sprague-Dawley rats were randomly assigned to normothermia ($37{\pm}1^{\circ}C$)-injurious ventilation (NT-V) group (n=10), hypothermia ($27{\pm}1^{\circ}C$)-injurious ventilation (HT-V) group (n=10), or nonventilated control group (n=7). The two thermal groups were subjected to injurious mechanical ventilation for 20 min with peak airway pressure 30 cm $H_2O$ at zero positive end-expiratory pressure, which was translated to tidal volume $54{\pm}6\;ml$ in the NT-V group and $53{\pm}4\;ml$ in the HT-V group (p>0.05). Results : Pressure-volume (P-V) curve after the injurious ventilation was almost identical to the baseline P-V curve in the HT-V group, whereas it was shifted rightward in the NT-V group. On gross inspection, the lungs of the HT-V group appeared smaller in size, and showed less hemorrhage especially at the dependent regions, than the lungs of the NT-V group. [Wet lung weight (g)/body weight (kg)] ($1.6{\pm}0.1$ vs $2.4{\pm}1.2$ ; p=0.014) and [wet lung weight/dry lung weight] ($5.0{\pm}0.1$ vs $6.1{\pm}0.8$ ; p=0.046) of the HT-V group were both lower than those of the NT-V group, while not different from those of the control group($1.4{\pm}0.4$, $4.8{\pm}0.4$, respectively). Protein concentration of the BAL fluid of the HT-V group was lower than that of the NT-V group($1,374{\pm}726\;ug/ml$ vs $3,471{\pm}1,985\;ug/ml$;p=0.003). Lactic dehydrogenase level of the BAL fluid of the HT-V group was lower than that of the NT-V group ($0.18{\pm}0.10\;unit/ml$ vs $0.43{\pm}0.22\;unit/ml$;p=0.046). Conclusions : Hypothermia attenuated pulmonary hemorrhage, permeability pulmonary edema, and alveolar cellular injuries associated with injurious mechanical ventilation, and preserved normal P-V characteristics of the lung in rats.

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Effect of Different Nutrient Solution and Light Quality on Growth and Glucosinolate Contents of Watercress in Hydroponics (배양액의 종류 및 광질이 물냉이의 생육 및 Glucosinolate 함량에 미치는 영향)

  • Choi, Jae Yun;Kim, Sung Jin;Bok, Kwon Jeong;Lee, Kwang Ya;Park, Jong Seok
    • Journal of Bio-Environment Control
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    • v.27 no.4
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    • pp.371-380
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    • 2018
  • Aim of this study was to investigate the effects of different nutrient solutions and various light qualities generated by LED on the growth and glucosinolates contents of watercress (Nasturtium officinale) grown under hydroponics for 3 weeks. The seeds of watercress were sown on crushed rockwool media and raised them for two weeks. They were transplanted in a semi-DFT (deep flow technique) hydroponics system. A controlled-environment room was maintained at $20{\pm}1^{\circ}C$ and $16{\pm}1^{\circ}C$ temperatures and $65{\pm}10%$ and $75{\pm}10%$ relative humidity (day and night, respectively), with a provided photosynthetic photon flux density (PPFD) of $180{\pm}10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and a photoperiod of 16/8h. To find out the best kinds of nutrient solutions for growing watercress, Otsuka House 1A (OTS), Horticultural Experiment Station in Korea (HES), and Netherland's Proefstaion voor Bloemisterij en Gasgroente (PBG) were adapted with initial EC of $1.0-1.3dS{\cdot}m^{-1}$ and pH of 6.2, irradiating PPFD with fluorescent lamps (Ex-1). Either monochromatic (W10 and R10) or mixed LEDs (R5B1, R3B1, R2B1G1, and W2B1G1) were irradiated with a differing ratio of each LED's PPFD to understanding light quality on the growth and glucosinolates contents of watercress (Ex-2). Although significant difference in the shoot growth of watercress was not found among three nutrient solutions treatments, but the root fresh weight increased by 13.7% and 55.1% in PBG and OTS compared to HES, respectively. OTS increased the gluconasturtiin content by 96% and 65% compared to PBG and HES. Compared with the white light (W10), the red light (R10) showed a 101.3% increase in the shoot length of watercress. Increasing blue light portion positively affected plant growth. The content of total glucosinolates in watercress was increased by 144.5% and 70% per unit dry weight in R3B1 treatment compared with R2B1G1 and W10 treatments, respectively. The growth and total glucosinolates contents of the watercress were highest under R3B1 among six light qualities.

Effect of moisture content on terminal velocities of domestic wheat and foreign materials (함수율에 따른 우리밀과 이물의 종말속도에 미치는 영향)

  • Choi, Eun-Jung;Kim, Hoon;Kim, Sang-Suk;Kim, Oui-Woung
    • Food Science and Preservation
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    • v.23 no.5
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    • pp.746-752
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    • 2016
  • This research was carried out to identify aerodynamic property as a function of moisture content for designing equipment such as for post-harvest management. Terminal velocity of two wheat varieties {Backjjung (B) and Jogyeong (J)} with selected sound, damaged kernel and foreign materials (Wheat stick, Wheat husks) were measured with a designed vertical wind column at different moisture contents from about 9 to 30% wet basis. The results showed that terminal velocity of wheat and foreign materials except of Jogyeong's husks (p<0.05) had a significant difference at p<0.001. With increasing moisture content, the aerodynamic property values of the kernels and foreign materials of the two wheat varieties increased linearly. In detail, terminal velocity of sound and damaged kernel increased from 5.46 to 7.13 m/sec (B) and 7.48 to 8.60 m/sec (J), damaged kernel from 5.91 to 7.00 m/sec (B) and 6.48 to 7.75 m/sec (J). For foreign materials the terminal velocity of wheat stick increased from 2.92 to 4.07 m/sec (B) and 3.74 to 5.22 m/sec (J) whereas that of husks from 1.07 to 1.85 m/sec (B) and 2.02 to 2.33 m/sec (J) each. For air separation of wheat and foreign materials, the air flow should be less than 5.22 m/sec due to the range (1.07~5.22 m/sec) of foreign materials in wheat.

Effect of Pulse Energy and Pulse Repetition Rate at the Identical Total Power During Enamel Ablation Using an Er:YAG Laser (Er:YAG 레이저를 이용한 치아 삭제시 동일출력에서 펄스에너지와 조사반복률의 영향)

  • Won, Jung-Yeon;Kim, Mee-Eun;Kim, Ki-Suk
    • Journal of Oral Medicine and Pain
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    • v.31 no.3
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    • pp.223-229
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    • 2006
  • The objectives of this study was to investigate the amount of tooth ablation and the change of intrapulpal temperature by Er:YAG laser as it relates to pulse energy and pulse repetition rate at the identical power and, thereby, to reveal which of the two parameters strongly relates with ablation efficiency and intrapulpal temperature. Extracted healthy human molar teeth were sectioned into two pieces and each specimen was irradiated within the combination of pulse energy and pulse repetition time at the same power of 3W; $300mJy{\times}10Hz$ group, $200mJy{\times}15Hz$ group, and $150mJy{\times}20Hz$ group. Each specimen comprised ten tooth specimens. A laser beam with conjunction of a water flow rate of 1.6 ml/min was applied over enamel surfaces of the specimens during 3 seconds and the ablation amount was determined by difference in weight before and after irradiation. To investigate the temperature change in the pulp according to the above groups, another five extracted healthy human molar teeth were prepared. Each tooth was embedded into resin block and the temperature-measuring probes were kept on the irradiated and the opposite walls in the dental pulp during lasing. When the power was kept constant at 3W, ablation amount increased with pulse energy rather than pulse repetition rate (p=0.000). Although intrapulpal temperature increased with pulse repetition rate, there were no significant differences among the groups and between the irradiated and the opposite pulpal walls, except at a condition of $150y{\times}20Hz$ (p=0.033). Conclusively, it is suggested that ablation efficacy is influenced by pulse energy rather than pulse repetition rate.

Predominant T Helper 1 Immune Response in Women with Reproductive Failures (반복 유산 및 착상실패를 보이는 환자에서 Th1 면역반응에 대한 연구)

  • Han, Ae-Ra;Yang, Kwang-Moon;KwakKim, Joanne
    • Clinical and Experimental Reproductive Medicine
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    • v.37 no.3
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    • pp.231-237
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    • 2010
  • Objective: To evaluate whether T helper 1 (Th1) immune response is predominant in women with reproductive failures (recurrent spontaneous abortion and recurrent implantation failure) and the activation of T cell is related to Th1 propensity. Methods: Women with a history of recurrent implantation failure or recurrent spontaneous abortion comprise the study group (n=37). Controls are normal fertile women without a history of infertility or pregnancy losses (n=11). Th1/Th2 ratios of interferon (INF)-$\gamma$/interleukin (IL)-10 and tumor necrosis factor (TNF)-$\alpha$/IL-10 expression on $CD3^+/4^+$ cells, CD154, and CD69 expression on T cells are measured by flow cytometric analysis. Results: The ratios of TNF-$\alpha$ to IL-10 expressing on $CD3^+/4^+$ cells (Th1/Th2 cell ratios) are significantly higher in study group ($42.1{\pm}2.3$) as compared with that of controls ($28.7{\pm}2.7$) (p=0.002). The overall trend of CD154 and CD69 expression on T cells are elevated in study group than those of controls. The proportion (%) of $CD3^+/4^+/154^+$ cells ($1.7{\pm}0.5$ vs. $0.3{\pm}0.2$, p=0.038) and the % of $CD3^+/8^+/154^+$ cells ($0.6{\pm}0.2$ vs. $0.1{\pm}0.0$, p=0.024) are significantly higher in study group. The % of $CD3^+/69^+$ cells ($5.6{\pm}1.9$ vs. $1.3{\pm}5.4$, p=0.046) and % of $CD3^+/8^+/69^+$ cells ($4.8{\pm}1.3$ vs. $1.8{\pm}0.2$, p=0.035) among $CD3^+/8^+$ cells are significantly increased in study group. Conclusion: Women with reproductive failures have Th1 propensity with increased T cell activation. These finding means that activated T cell has a harmful effect on early pregnancy and implantation by induction of Th1 immunity.

Various Possibilities of Dispositif Film (디스포지티프 영화의 다양한 가능성)

  • KIM, Chaehee
    • Trans-
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    • v.3
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    • pp.55-86
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    • 2017
  • This study begins with the necessity of the concept of reincarnation of film media and the inclusion of specific tendencies of contemporary films as post - cinema comes. Variable movements around recent films Challenging and experimental films show aesthetics that are difficult to approach with the analysis of classical mise en scene and montage. In this way, I review the dispositif proposed by Martin in films that are puzzling to criticize with the classical conceptual framework. This is because the concept of dispositive is a conceptual pile that extends more than a mise en scene and a montage. Dispositif films tend to be non-reproducible and non-narrative, but not all non-narrativef tendencies are dispositif films. Only the dispositif film is included in the flow. Dispositif movement has increased dramatically in the modern environment on which digital technology is based, but it is not a tendency to be found in any particular age. The movement has been detected in classical films, and the dispositif tendency has continued to exist in avant-garde films in the 1920s and some modernist films. First, for clear conceptualization of cinematic dispositif, this study examines the sources of dispositif debates that are being introduced into film theory today. In this process, the theory of Jean Louis Baudry, Michel Foucault, Agamben, Flusser, and Deleuze will help. The concept of dispositif was discussed by several scholars, including Baudry and Foucault, and today the notion of dispositif is defined across all these definitions. However, these various discussions are distinctly different from the cinematic dispositif or dispositif films that Martin advocates. Martin's proposed concept reminds us of the fundamentals of cinematic aesthetics that have distinguished between the mise-en-scene and the montage. And it will be able to reconsider those concepts and make it possible to view a thing a new light or create new films. The basic implications of dispositif are apparatus as devices, disposition and arrangement, the combination of heterogeneity. Thus, if you define a dispositif film in a word, it is a new 'constraint' consisting of rearrangement and arrangement of the heterogeneous elements that make up the conditions of the classical film. In order for something to become a new design, changes must be made in the arrangement and arrangement of the elements, forces, and forces that make up it. Naturally, the elements encompass both internal and external factors. These dispositif films have a variety of possibilities, such as reflection on the archival possibilities and the role of supervision, the reestablishment of active and creative audience, the reason for the film medium, and the ideological reflection. films can also 'network' quickly and easily with other media faster than any medium and create a new 'devised' aesthetic style. And the dispositif film that makes use of this will be a key keyword in reading the films that present the new trend of modern film. Because dispositif are so comprehensive and have a broad implication, there are certainly areas that are difficult to sophisticate. However this will have a positive effect on the future activation of dispositif studies end for end. Dispositif is difficult to elaborate the concept clearly, so it can be accessed from a wide range of dimensions and has theoretically infinite extensibility. At the beginning and end of the 21st century film, the concept of cinematic dispositif will become a decisive factor to dismantle old film aesthetics.

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Mock-up Test of Temperature Crack Reduction Method Application by Setting Time Control of Mat Foundation Mass Concrete (응결시간조정에 의한 매트기초 매스 콘크리트의 온도균열저감 공법적용의 Mock-up Test)

  • Han, Cheon-Goo;Lee, Jae-Sam;Noh, Sang-Kyun
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.4
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    • pp.55-61
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    • 2009
  • Recently, the number of high-rise buildings being built in Korea by major construction companies for residential and commercial use has been increasing. When constructing a high-rise building, it is necessary to apply massive amounts of concrete to form a mat foundation that can withstand the huge load of the upper structure. However, it is of increasing concern that due to limitations in terms of the amount of placing equipment, available job-sites and systems for mass concrete placement in the construction field, it is not always possible to place a great quantity of concrete simultaneously in a large-scale mat foundation, and for this reason consistency between placement lift cannot be secured. In addition, a mat foundation Is likely to crack due to the stress caused by differences inhydration heat generation time. To derive a solution for these problems, this study provides test results of a hydration heat crack reduction method by applying placement lift change and setting time control with a super retarding agent for mass concrete in a large-scale mat foundation. Mock-up specimens with different mixtures and placement liftswere prepared at the job-site of a newly-constructed high-rise building. The test results show that slump flow of concrete before and after adding the super retarding agent somewhat Increases as the target retarding time gets longer, while the air content shows no great difference. The setting time was observed to be retarded as the target retarding time gets longer. As the target retarding time gets longer, compressive strength appears to be decreased at an early stage, but as time goes by, compressive strength gets higher, and the compressive strength at 28 days becomes equal or higher to that of plain concrete without a super retarding agent. For the effect of placement lift change and super retarding agent on the reduction of hydration heat, the application of 2 and 4 placement lifts and a super retarding agent makes it possible to secure consistency and reduce temperature difference between placement lifts, while also extending the time to reach peak temperature. This implies that the possibility of thermal crack induced by hydration heat is reduced. The best results are shown in the case of applying 4 placement lifts.