• 沒有找到結果。

5.1 結論

由於網際網路的發達,造成消費習慣的改變,以往利用單一別揀取,在 多樣少量或少樣少量的市場已不適用,而訂單批次處理是一個不錯之選擇。

另外,在不同之訂單數量規模的物流中心也可針對本研究之結果找尋適合自 己之揀貨系統。綜合前面研究之結果,我們可以得到以下幾點結論:

一、在本研究所提之兩種批次處理演算法,在少樣少量的市場下確實比使用 單一訂單揀取法則來的恰當。在訂單數為1000的情況下,比單一訂單揀 取所減少之總作業時間約有1.6倍之多,在車輛滿載率方面也將近有99%

以上;而批次處理所要擔心的出錯率問題,以現今電腦及輔助設備之發 達,應可針對相關設備作一改善,進而減少此問題之產生。

二、無論訂單數為何,在儲位指派方面,均是採用通道間法較佳,採用橫越 法較差,其順序也與PetersenII & Schmenner【32】所提出之研究結果相 同;在需求程度方面,則採用高需求程度所得之績效較佳。

三、在分區規劃方面,無論採用哪種水準,而且隨著處理之訂單數減少,其 因子幾乎沒影響。由於採用修正SMA法時,只判斷走道數之增加,當訂 單數很大時(1000張訂單),在分區規劃上搭配分五區,會有較佳之表 現;而採用SMTTD法時,則搭配不分區較好。若該物流中心所處理之訂 單數很少時,無須考慮分區規劃。

四、就所有組合表現來看,影響整個揀取距離之優劣主要是儲位指派及需求 程度,無論處理之訂單為何,當使用通道間法搭配高需求程度時,其他 因子無論採用何種水準,均有不錯之表現。而使用橫越法搭配低需求程 度時,其績效表現較差。

五、在本研究所提之兩種批次處理演算法中,無論訂單數之多寡,SMTTD法 除了在電腦處理時間上較修正SMA法差外,但在總揀貨旅行距離、總作 業時間、總揀貨旅行次數及車輛滿載率上均優於修正SMA法;而使用此 兩種訂單批次方法時,在車輛滿載率方面均可達到98%以上,且電腦處 理時間最大也只有35秒左右。雖然SMTTD法與修正SMA法各有優劣,就

車輛滿載率及電腦處理時間而言,這兩種方法均是不錯的批次處理方法。

六、使用SMTTD法或修正SMA法時,其平均揀取一張訂單所需之總作業時 間,隨著訂單數之減少,其平均揀取一張訂單所需作業之總時間會增加,

其差異最大約有0.1分鐘。以SMTTD法來說,若將1000張訂單分二次處 理,即一次只做500張之批次處理與一次處理1000張訂單所花費之時間,

在批次處理時間上約可減少17秒,但在總作業時間上卻要多花30分鐘。

故若單一時間內處理之訂單數量大時,仍建議一次做批次處理,而不要 分批處理。

5.2 建議

由於此次研究著重在批次處理演算法,故部份之議題未能一一探討,茲 列舉幾項可供後續研究之建議:

一、根據以往之研究均建議其倉儲環境為寬扁形的倉儲空間較佳,而本研究 之倉儲環境約為正方形,故可將其倉儲環境改為寬扁形,或許能得到更 佳之績效。

二、本研究未將揀貨路徑策略一併探討,故未來在揀貨作業上建議可將合併 後的批次訂單,依其特性找尋適當之揀貨路徑策略,或直接將揀貨路徑 策略一併考量。

三、採用高需求程度之ABC儲存法則時,可能會使訂單過度集中於某幾個走 道,進而使揀貨人員在揀取物品時造成壅塞之現象,故未來也可針對這 部分做更進一步之分析與改善。

四、以往之研究均是改善硬體設施來降低成本,但一物流中心揀貨作業之好 壞不只是硬體設備而已,還包括揀貨人員之配置與調度,故未來或許可 將揀貨人員之規劃也一併探討,以其更能符合整體之效益。

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