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Energy Loss of Hydrogen Atom due to Charge Exchange in Neutral Particle Energy Analyzer (중성입자 에너지 분석장치에서 전하교환용 탄소박막에 의한 수소원자의 에너지 손실특성)

  • Kim, Kye-Ryung;Kim, Wan;Lee, Yong-Hyun;Kang, Hee-Dong
    • Journal of Sensor Science and Technology
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    • v.7 no.3
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    • pp.179-187
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    • 1998
  • A neutral particle energy analyzer, which has the carbon stripping foil and the $90^{\circ}$ cylindrical electrostatic deflection plate, was designed and constructed for measuring of ion temperature in plasma. The energy calibration and energy resolution were studied in detail for a hydrogen ion at the $0.5{\sim}3.0\;keV$ energy using a duoplasmatron ion source. An energy of hydrogen ion to the deflection plate voltage at the peak ion count rate could be fitted by the expression $E_{o}(keV)$=3.83V(kV). The measured energy resolution, which was about 2 % at the energy of 3.0 keV and 9 % at the energy of 0.5keV, was better for the increased hydrogen ion energy. For the charge exchanged hydrogen atom due to the carbon stripping foil, the energy calibration, energy loss and resolution were measured to the $0.5{\sim}2.0{\mu}g/cm^{2}$ thickness of the carbon stripping foil. An energy of the charge exchanged hydrogen atom as a function of the deflection plate voltage and carbon foil thickness could be fitted by the expression $E_{o}(keV)=(0.53d+4.4){\cdot}V(kV)$. The energy loss was $0.23{\sim}0.89\;keV $ to the $0.5{\sim}2.0{\mu}g/cm^{2}$ carbon foil thickness and the $0.5{\sim}3.0\;keV$ energy of the incident neutral hydrogen atom, it could be fitted by the expression ${\Delta}E=(0.12d+0.27){\cdot}{E_{o}}^{1/2}(keV)$. The measured energy resolution for the neutral hydrogen atom, which was between 7 % and 35 % in this experiment region, was increased for the increasing neutral hydrogen atom energy and the decreasing carbon stripping foil thickness.

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Chemical Component of Red Onion (Allium cepa L.) according to Cultivars and Growing Areas (품종, 지역에 따른 적색양파 화학성분)

  • Moon, Jin-Seong;Kim, Hee-Dae;Ha, In-Jong;Lee, Sun-Young;Lee, Jong-Tae;Lee, Sang-Dae
    • Horticultural Science & Technology
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    • v.28 no.6
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    • pp.921-927
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    • 2010
  • The objective of this study was to improve the breeding efficiency and consumption of red onion by analysis of chemical components. The red cultivar S&P5294 ($52.9mg{\cdot}g^{-1}$ F.W.) resulted in the highest sugar content, and sweetness whereas 'Redprime' had the lowest. For the pyruvic acid content the cultivar 'Redsun' showed the highest value, followed by 'Sunpower' (yellow onion) and S&P7270. Breeding lines had higher sugar content and sweetness than 'Redprime' and 'Sunpower', while they had less pyruvic acid value than 'Redsun' and 'Sunpower'. The the same trend was verified for the total phenol and total flavonoid, of which breeding lines were found to have more content than 'Redprime' or 'Sunpower'. Three major flavonoids, rutin (quercetin glycoside), myricetin, and quercetin, were identified and quantified whereas kaempferol was not detected in all cultivars. Rutin was the major flavonoid present in all cultivars (136.9 to $169.9{\mu}g{\cdot}g^{-1}$ F.W.), followed by quercetin (62.5 to $135.7{\mu}g{\cdot}g^{-1}$ F.W.). Relatively smaller amount of myricetin (11.2 to $16.1{\mu}g{\cdot}g^{-1}$ F.W.) was also detected. Among nine cultivars, 'Redsun' exhibited significantly ($p$ < 0.05) higher content of quercetin and rutin (135.7 and $169.9{\mu}g{\cdot}g^{-1}$ F.W., respectively), and S&P5296 had the highest content of myricetin($16.1{\mu}g{\cdot}g^{-1}$ F.W.). Breeding lines had more quercetin, rutin and myricetin contents than the cultivars 'Redprime' and 'Sunpower'. Hampyeong had the highest content for total phenol and total flavonoid, followed by Andong and Changyeong whereas Changyeong had the highest value for rutin, myricetin and quercetin followed by Hampyeong and Andong. Among red onion cultivars, 'Redsun' showed the highest value for anthocyanin, followed by S&P5295 and S&P5296, which the cultivar 'Redprime' had significantly (p<0.05) lower content(35.5 mg%).

Monitoring of Biosafety of Agricultural Products from Urban Community Gardens and Roof Gardens in Korea (도시텃밭과 옥상정원에서 재배되는 농산물의 생물학적 안전성 조사)

  • Kim, Jin-Won;Yu, Yong-Man;Na, Won-Seok;Baljii, Enkhjargar;Choi, In-Wook;Youn, Young-Nam;Lee, Young-Ha
    • Horticultural Science & Technology
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    • v.32 no.3
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    • pp.400-407
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    • 2014
  • Urban farming supplies emotional stability and fresh vegetables to participating persons, however, no information regarding the biosafety of agricultural products from urban farming is available. Here, we collected 260 samples of Chinese cabbages and lettuce from 4 urban community gardens and 6 roof gardens in Seoul from September through October 2012, and monitored the microbiological and parasitological contamination quantitatively and/or qualitatively. The mean counts of total aerobic bacteria and coliforms were $6.1{\pm}0.8\;log\;CFU{\cdot}g^{-1}$ ( range, $5.4{\pm}0.6{\sim}7.1{\pm}0.8\;log\;CFU{\cdot}g^{-1}$) and $4.0{\pm}0.7\;log\;CFU{\cdot}g^{-1}$ (range, $2.3{\pm}0.6{\sim}6.1{\pm}0.9\;log\;CFU{\cdot}g^{-1}$), respectively. Coliforms were detected on 59.6% among 260 vegetable samples. There were no significant differences in the contamination levels of total aerobic bacteria and coliforms between the Chinese cabbages and lettuce, whereas both levels of vegetables from urban community gardens were higher than those of roof gardens (p > 0.05). Escherichia coli was isolated at 3.1% among whole vegetables, and contamination level was $1.5{\pm}0.2\;log\;CFU{\cdot}g^{-1}$. Among foodborne pathogens, Staphylococcus aureus was detected in 1.5%, however, Salmonella spp., Listeria monocytogenes and E. coli O157:H7 were not detected on any of the vegetable samples. We also found undefined parasite eggs from two samples of Chinese cabbages (0.8% of total vegetables we tested). From these study, we found the presence of microbial contamination of agricultural products from urban farming, thus we need further concern to improve the biosafety during production of agricultural products.

Effect of Hot-water Dipping on Inhibiting Red Discoloration of Basal Part in Chicon (열수 침지 처리가 치콘 절단면의 적변 억제에 미치는 영향)

  • Jung, Hyun Jin;Kang, Ho-Min
    • Horticultural Science & Technology
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    • v.32 no.3
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    • pp.353-358
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    • 2014
  • Hot water dipping test was conducted for chicon to restrict red discoloration of its basal part which impairs the product value during sales. Hot water dipping treatment was given to chicon for 4 min and for 8 min at $38^{\circ}C$ and for 2 min and 4 min at $42^{\circ}C$, and for 1 min and 2 min at $45^{\circ}C$, along with control (for one min at $20^{\circ}C$). The red discoloration indices of basal part of chicon during sensory evaluation on the sixth day of storage under the storage temperature at $10^{\circ}C$ was lower at $42^{\circ}C$ for 2 min, $42^{\circ}C$ for 4 min and $45^{\circ}C$ for 1 min treatments. The color change value of the basal part in chicon measured by colorimeter showed that the lowest ${\Delta}a^*$ and ${\Delta}h$ were maintained in the basal part of chicon treated at $42^{\circ}C$ for 2 min. Whereas, color changes in $42^{\circ}C$ for 2 min and $45^{\circ}C$ for 1 min treatments were significantly low as compared with that of control. The contents of total phenolic compounds which are the substances that cause red discoloration of basal part in chicon were lowest at $42^{\circ}C$ for 2 min, $42^{\circ}C$ for 4 min and $45^{\circ}C$ for 1 min treatments. The activity of phenylalanine ammonia lyase (PAL) resposible for in the synthesis of phenolic substances was the least in $42^{\circ}C$ for 2 min treatment. Whereas, PAL activity of the chicons treated a t $42^{\circ}C$ for 2 min and at $45^{\circ}C$ for 1 min were significantly lower than that of control. However, red discoloration was progressed as similar level with that of control in the basal part of chicon at $45^{\circ}C$ for 2 min. The contents of total phenolic compounds and PAL activity in this treatment were not significantly different from those in control. The polyphenol oxidase (PPO) activity which causes red discoloration of cut tissues was low in all the treatments including $42^{\circ}C$ and $45^{\circ}C$ treatment at which no inhibition effects of the red discoloration of basal part of chicon were observed. When the correlation coefficient between each investigated index was tested, most of them showed high correlation except the PPO activity and particularly and the red discoloration index and sensory evaluation ${\Delta}h$ values, and PAL activity and total phenolic compounds content were $r=0.927^{**}$, and $r=0.942^{**}$, respectively.

Biogas Production from Anaerobic Co-digestion Using the Swine Manure and Organic Byproduct (돈분과 유기성 부산물을 혼합한 혐기소화에서 바이오가스 생산)

  • Kim, W.G.;Oh, I.H.;Yang, S.Y.;Lee, K.M.;Lee, S.I.
    • Journal of Animal Environmental Science
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    • v.17 no.1
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    • pp.49-54
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    • 2011
  • Animal manure is produced annually 43.7 million tonnes in Korea. Among them, about 85.6 % are used as compost or liquid fertilizer to the agricultural land. The animal manure can be effectively utilized by mixing with organic byproducts that result in generation of biogas from anaerobic co-digestion process. This study aimed to optimize the content of total solid materials (TS) and determine the effect of organic byproduct on the co-digestion process. Prior to the byproduct treatments, determination of proper content of TS was conducted by controlling at 5 or 10 %. For the byproduct treatments, swine manure without adding the byproduct was used for control treatment, and swine manure mixed with either corn silage or kitchen waste was used for other treatments. Volume of biomethane ($CH_4$) generated from digested materials was quantified before and after byproduct treatments. In result, a 1.4-fold higher biomethane, about 0.556 L/$L{\cdot}d$, was produced when the content of TS was controlled at 10 %, compared at 5 %, about 0.389 L/$L{\cdot}d$. When the swine manure was mixed with the corn silage or kitchen waste, a two-fold higher biomethane was produced, about 1.theand 1.0heL/$L{\cdot}d$, respectively, compared to the control treatment. Biogas production from organic dry matter (odm) was a3, 362eand 2h6 L/kg odm${\cdot}$d for control, corn silage, and kitchen waste treatment, respectively. The lower biogas production in the treatment of kitchen waste than that of corn silage is associated with its relatively high odm contents. The methane concentration during the whole process ranged from 40 at the beginning to 70 % at the end of process for both the control and kitchen waste treatments, and ranged from 52 to 70 % for the corn silage treatment. Hydrogen sulfide ($H_2S$) concentration ranged between 350 and 500 ppm. All the integrated results indicate that addition of organic byproduct into animal manure can double the generation of biogas from anaerobic fermentation process.

Studies on Variation of Characteristics in Hanwoo Steers by Pen and Group Size (한우 거세우의 군집크기에 따른 산육특성 연구)

  • Ha, J.J.;Rhee, Y.J.;Jang, W.J.;Kim, Y.W.;Shaogang, Li;Song, Y.H.
    • Journal of Animal Environmental Science
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    • v.15 no.1
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    • pp.9-16
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    • 2009
  • This study, tasting 14 months, was conducted to investigate the effects of different pen size and group size on growing-fattening characteristics of Hanwoo steers. Forty-eight, 12-month-old Hanwoo steers($305.8{\pm}32.2\;kg$) were randomly assigned to three groups($35.28\;m^2$; n=4 heads, $70.56\;m^2$; n=8 heads, $105.84\;m^2$; n=12 heads) and reared in separate pens with a constant space allowance of $8.82m^2$ per head from 12 to 21 month of age and then regrouped to 4 heads per pen. A common diet including concentrate(limited) and forage(ad lib) was provided to all the animals. Images of live animal ultrasonic back fat thickness, longissimus muscle area and Marbling score were evaluated in three months interval from 12 months of age using an ultrasound equipment(HS-2000) at the 13th rib and lumber vertebra interface of left side. Significant differences of ADG was found mainly at $15{\sim}18$ month and $18{\sim}21$ month fattening stages(p<0.05). Marbling score(MS) was higher(p<0.05) in 12 heads group when compared with that of 4 and 8 heads groups after 18 months. Animals in 12 heads group had the lowest Average daily gain(ADG) but showed the highest longissimus muscle area(LMA) and marbling score(MS). In addition, Hanwoo steers in 12 heads group obtained a higher quality appearance(HQA) of 82.7% than that of other treatments. The results indicated that Hanwoo steers housed on large group size and pen size decreased their ADG but improved meat quality.

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Chemical Composition and Fermentation Characteristics of the Corn Silage During Feedout at Yonchon of Gyeonggi-do (연천지역에 있어서 옥수수 사일리지의 개봉 후 경과기간에 따른 시료성분 및 발효품질)

  • Sung Kyung Il;Kim Gon Sik;Lee June Woo;Kim Byung Wan;Kim Sang Rok
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.25 no.1
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    • pp.43-50
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    • 2005
  • The purpose of this study is to discuss the ways to consistently feed high quality corn silage(CS). This study evaluated the effect of the corn silage, after a certain time has elapsed, on the chemical composition and fermentation characteristics after feedout during the winter feeding period of the CS. Six samples of CS from four dairy farms(E1, E2, E3, and L1 ) were taken in order to feed the milking cows over a winter feeding Period from November of 2002 until February of the following year, 2003(six samples were taken at the fellowing dates in the following order: sample one was taken on the 23rd Nov. 2002, sample two on the 5th of Dec. 2002, 3rd sample on the 23rd of Dec. 2002, 4th sample on the 7th of Jan. 2003, 5th sample on the 22nd of Jan. 2003, and the 6th sampling was carried out on the 6th of Feb. 2003) at the three sampling sites after the opening of the trench silos at intervals of 15 days. In the dry matter contents of CS, there wasn't any specific tendency according to the elapsed time in the range of 21.3~$27.3\%$ at all low dairy farm(E1, E2, E3, and L1). And the average dry matter contents were 24.1, 25.9, 23.6, and $20.4\%$. Considering the Proper amount of the dry matter of CS during the ripen yellow stage, the appropriate moisture content was $33\%$ (NRC, 1989), and these dry matter contents were all low. A consistent tendency was not found in the contents of CS. The average of CP contents were 10.2, 8.0, 8.5, and $9.8\%$ at the E1, E2, E3, and L1 farms, and there were significant differences. The TDN contents of CS were not different among forms according to the time elapsed. The pH, according to the time elapsed after opening of the CS, there were no differences at each of E1, E2, E3, md L1 farms. Average pH were 3.5, 3.9, 3.6, and 4.1, md all of them were in normal range. In the lactic acid contents of CS, a consistent tendency was not found among four farms. But according to the time elapsed. there was a goat difference from 1.13~$7.8\%$ The acetate, propionate, and butyrate contents of CS were very low. In this study, there was no significant difference in the CS's chemical composition and fermentation characteristics according to the elapsed time at all four dairy farms. Considering the proper dry matter contents of CS during the ripen yellow stage, the appropriate dry matter content was $33\%$, and dry matter contents of few farms were all low. To enhance the quality of corn silage should be ensiled com at proper dry matter content range from 28 to $35\%$ Therefore, content of the corn plant should be always be closely monitored prior to beginning harvest.

The difference of photosynthetic efficiency and electron transport rate by control of the red tide organism using algicidal substance and yellow clay (살조물질과 황토를 이용한 적조생물 제어에 따른광합성 효율 및 전자전달율의 차이)

  • Son, Moonho;Baek, Seung Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2951-2957
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    • 2015
  • The development of worldwide harmful algal blooms(HAB) is a serious problem for public health and fisheries industries. To evaluate the algicidal impact on the HAB species, algicide thiazolidinedione derivative (TD49) and yellow clay were examined, which is focus on assess the algicidal effects and inhibition to photosynthesis of HAB species. To obtain the detailed information, we analyzed the viability of target species related to activity Chl. a, photosynthetic efficiency($F_v/F_m$), and electron transport rate(ETR). Culture experiment was conducted to evaluate the algicidal effects of three harmful species(raphidophyceae Heterosigma akashiwo, Chattonella marina, and dinophyceae Heterocapsa circularisquama) and one non-harmful species (cryptophyceae Rhodomonas salina). Our experiments revealed that three HAB species were easily destroyed of the cell walls after TD49 dosing. Also, they had significantly reducing values of active Chl. a, $F_v/F_m$, and ETR, due to the damage of photosystem II by inter-cellular disturbance. As a result, the algicidal effect(%) for the three HABs were as follows, in the order of greatest to the least: H. circularisquama> C. marina> H. akashiwo. However, the algicidal effect for yellow clay remained to be <30% (p>0.01), implying that it may not have damaged the photosystem II. On the other hand, non-HAB R. salina was promoted at both TD49 and yellow clay treatments. Our results demonstrated that the TD49 is a good agent for the control of HABs H. akashiwo, C. marina, and H. circularisquama, whereas the yellow clay would not be suitable for the field application based on our experimental results.

Understanding the Protox Inhibition Activity of Novel 1-(5-methyl-3-phenylisoxazolin-5-yl)methoxy-2-chloro-4-fluorobenzene Derivatives Using Comparative Molecular Similarity Indices Analysis (CoMSIA) Methodology (비교 분자 유사성 지수분석(CoMSIA) 방법에 따른 1-(5-methyl-3-phenylisoxazolin-5-yl)methoxy-2-chlore-4-fluorobenzene 유도체들의 Protox 저해 활성에 관한 이해)

  • Song, Jong-Hwan;Park, Kyung-Yong;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.47 no.4
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    • pp.414-421
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    • 2004
  • 3D QSAR studies for protox inhibition activities against root and shoot of the rice plant (Orysa sativa L.) and barnyardgrass (Echinochloa crus-galli) by a series of new 1-(5-methyl-3-phenylisoxazolin-5-yl)methoxy-2-chloro-4-fluorobenzene derivatives were conducted based on the results (Sung, N. D. et al.'s, (2004) J. Korean Soc. Appl. Biol. Chem. 47(3), 351-356) using comparative molecular similarity indices analysis (CoMSIA) methodology. Four CoMSIA models, without hydrogen bond donor field for the protox inhibition activities against root and shoot of the two plants, were derived from the combination of several fields using steric field, hydrophobic field, hydrogen bond acceptor field, LUMO molecular orbital field, dipole moment (DM) and molar refractivity (MR) as additional descriptors. The predictabilities and fitness of CoMSIA models for protox inhibition activities against barnyard-grass were higher than that of rice plant. The statistical results of these models showed the best predictability of the protox inhibition activities against barnyard-grass based on the cross-validated value $r^2\;_{cv}\;(q^2=0.635{\sim}0.924)$, non cross-validated, conventional coefficient $r^2\;_{ncv.}$ value $(r^2=0.928{\sim}0.977)$ and PRESS value $(0.255{\sim}0.273)$. The protox inhibition activities exhibited a strong correlation with the steric $(5.4{\sim}15.7%)$ and hydrophobic $(68.0{\sim}84.3%)$ factors of the molecules. Particularly, the CoMSIA models indicated that the groups of increasing steric bulk at ortho-position on the C-phenyl ring will enhance the protox inhibition activities against barnyard-grass and subsequently increase the selectivity.

NIRS Calibration Equation Development and Validation for Total Nitrogen Contents Field Analysis in Fresh Rice Leaves (벼 생엽의 질소함량 현장분석을 위한 NIRS 검량식 개발 및 검증)

  • Song, Young-Eun;Lee, Deok-Ryeol;Cho, Seong-Hyun;Lee, Ki-Kwon;Jeong, Jong-Seong;Gwon, Yeong-Rip;Cho, Kyu Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.58 no.3
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    • pp.301-307
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    • 2013
  • This study was evaluated high end research grade Near Infrared Reflectance Spectrophotometer (NIRS) to field grade multiple Near Infrared Reflectance Spectrophotometer (NIRS) for rapid analysis at fresh rice leaf at sight with 238 samples of fresh rice leaf during year 2012, collected Jeollabuk-do for evaluate accuracy and precision between instruments. Firstly collected and build database high end research grade NIRS using with 400 nm ~ 2500 nm during from year 2003 to year 2009, seven years collected fresh rice leaf database then trim and fit to field grade NIRS with 1200 nm ~ 2400 nm then build and create calibration, transfer calibration with special transfer algorithm. The result between instruments was 0.005% differences, rapidly analysis for chemical constituents, Total nitrogen in fresh rice leaf within 5 minutes at sight and the result equivalent with laboratory data. Nevertheless last during more than 8 years collected samples for build calibration was organic samples that make differentiate by local or yearly bases etc. This strongly suggest population evaluation technique needed and constantly update calibration and maintenance calibration to proper handling database accumulation and spread out by knowledgable control laboratory analysis and reflect calibration update such as powerful control center needed for long lasting usage of fresh rice leaf analysis with NIRS at sight. Especially the agriculture products such as rice will continuously changes that made easily find out the changes and update routinely, if not near future NIRS was worthless due to those changes. Many research related NIRS was shortly study not long term study that made not well using NIRS, so the system needed check simple and instantly using with local language supported signal methods global distance (GD) and neighbour distance (ND) algorithm. Finally the multiple popular field grades instruments should be the same results not only between research grade instruments but also between multiple field grade instruments that needed easily transfer calibration and maintenance between instruments via internet networking techniques.